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1.
Objective  This study is to determine the effect of the natural product parthenolide, a sesquiterpene lactone isolated from extracts of the herb Tanacetum parthenium, on the proliferation of vascular smooth muscle cells (VSMCs). Methods  Rat aortic VSMCs were isolated and cultured in vitro, and treated with different concentrations of parthenolide (10, 20 and 30 μmol/L). [3H]thymidine incorporation was used as an index of cell proliferation. Cell cycle progression and distribution were determined by flow cytometric analysis. Furthermore, the expression of several regulatory proteins relevant to VSMC proliferation including IκBα, cyclooxygenase-2 (Cox-2), p21, and p27 was examined to investigate the potential molecular mechanism. Results  Treatment with parthenolide significantly decreased the [3H]thymidine incorporation into DNA by 30%∼56% relative to control values in a dose-dependent manner (P<0.05). Addition of parthenolide also increased cell population at G0/G1 phase by 19.2%∼65.7% (P<0.05) and decreased cell population at S phase by 50.7%∼84.8% (P<0.05), which is consistent with its stimulatory effects on p21 and p27. In addition, parthenolide also increased IκBα expression and reduced Cox-2 expression in a time-dependent manner. Conclusion  Our results show that parthenolide significantly inhibits the VSMC proliferation by inducing G0/G1 cell cycle arrest. IκBα and Cox-2 are likely involved in such inhibitory effect of parthenolide on VSMC proliferation. These findings warrant further investigation on potential therapeutic implications of parthenolide on VSMC proliferation in vivo. Project (No. 491020-W50315) supported by the Foundation of the Health Bureau of Zhejiang, China  相似文献   

2.
Objective: To explore the relationship between genetic polymorphisms in methylenetetrahydrofolate reductase (MTHFR), methionine synthase reductase (MTRR), the central enzymes in folate metabolism that affects DNA methylation and synthesis, and the risk of Down syndrome in China. Methods: Genomic DNA was isolated from the peripheral lymphocytes of 64 mothers of children with Down syndrome and 70 age matched control subjects. Polymerase chain reaction and restriction fragment length polymorphism were used to examine the polymorphisms of MTHFR 677C→T, MTRR 66A→G and the relationship between these genotypes and the risk of Down syndrome was analyzed. Results: The results show that the MTHFR 677C→T polymorphism is more prevalent among mothers of children with Down syndrome than among control mothers, with an odds ratio of 3.78 (95% confidence interval (CI), 1.78～8.47). In addition, the homozygous MTRR 66A→G polymorphism was independently associated with a 5.2-fold increase in estimated risk (95% CI, 1.90～14.22). The combined presence of both polymorphisms was associated with a greater risk of Down syndrome than the presence of either alone, with an odds ratio of 6.0 (95% CI, 2.058～17.496).The two polymorphisms appear to act without a multiplicative interaction. Conclusion: MTHFR and MTRR gene mutation alleles are related to Down syndrome, and CT, TT and GG gene mutation types increase the risk of Down syndrome.  相似文献   

3.
Objective: To evaluate the effects oftramadol on the proinflammatory responses in a rat model of incisional pain by investigating its effects on nociceptive thresholds and serum interleukin-6 (IL-6) and IL-2 levels. Methods: Forty-two male Sprague-Dawley (SD) rats scheduled for plantar incision were randomly divided into 7 groups (n=6 in each group). Rats in Group 1 receiving general anesthesia with no incision were served as control; At 30 min before skin incision, Groups 2～5 were given 5 ml normal saline or 1, 10, and 20 mg/kg tramadol, respectively, intraperitoneally (i.p.); Group 6 received 10 mg/kg tramadol after operation; Group 7 received 10 mg/kg tramadol before incision, followed by 200 μg/kg naloxone after operation. Mechanical allodynia was measured by electronic von Frey filament to evaluate the nociceptive thresholds 1 h before incision, and 1 h and 2 h after operation. Serum IL-6 and IL-2 levels were measured by enzyme-linked immunosorbent assay (ELISA) 2 h after operation. Results: Mechanical thresholds decreased significantly and serum IL-6 level increased significantly after operation in Group 2 compared with control (P＜0.01), and these changes were reversed respectively by tramadol in a dose-dependent manner (P＜0.05 and P＜0.01, respectively). IL-2 level remained unchanged after operation in Group 2, but decreased in Group 3 (P＜0.05), then gradually returned to the normal level in Groups 4 and 5. The intraperitoneally injected tramadol (10 and 20 mg/kg) produced a potent and dose-dependent antinocicptive effect on the lesioned paw. The antinocicptive effects of tramadol were partially an-tagonized by naloxone (200 μg/kg), suggesting an additional non-opioid mechanism. Conclusion: The results suggest that tramadol could be a good choice for the treatment of pain under the conditions that immunosuppression may be particularly contraindicated.  相似文献   

4.
Objective： To investigate the association of Graves＇ disease and Graves＇ ophthalmopathy with the C/T transition polymorphism at position -318 of promoter and the A/G transition polymorphism at position 49 of exon 1 within cytotoxic T lymphocyte associated antigen-4 （CTLA-4） gene. Methods： Thirty-three patients with ophthalmopathy of Graves＇ disease, fifty-six Graves＇ patients without ophthalmopathy and sixty normal subjects as control were involved in the present case-control study. The polymorphisms were evaluated by polymerase chain reaction fragment length polymorphism （PCR-RFLP）. Comparisons were made of gene frequencies and allele frequencies between the groups. Results： The gene frequencies of CT and allele frequencies of T were much higher in Graves＇ patients with ophthalmopathy than that in the group without ophthalmopathy （P=-0.020, P=-0.019）. The gene frequencies of GG and allele frequencies of G in patients with Graves＇ disease were significantly increased as compared with control group （P=0.008, P=0.007）. The data suggest that smokers with Graves＇ disease seemed to be more predisposed to ophthalmopathy than non-smokers （P=0.018）. Conclusion： Our results suggest that an allele of T at position -318 of promoter is associated with genetic susceptibility to Graves＇ ophthalmopathy while an allele of G at position 49 of exon 1 is associated with genetic susceptibility to Graves＇ disease instead. Smoking is believed to be a major risk factor for ophthalmopathy.  相似文献   

5.
Objective： The aim of this retrospective investigation was to explore the influence of femoral osteoporosis on short-term curative effects ofcementless hip arthroplasty and to evaluate the femoral metaphyseal bone mineral density （BMD） for femoral osteoporosis in order to guide prosthesis choice and rehabilitation. Methods： We performed 127 total arthroplasty operations between June 1999 to February 2003 and investigated 49 cementless hip replacements with the Metalcancellous cementless Lubeck Ⅱ system being used in all hips. There were twenty men and twenty-nine women whose mean age at the time of the operation was 60 years （range, 52-81 years）. The patients were divided into osteoporosis or normal groups according to the femoral metaphyseal BMD measured preoperatively. The average duration of follow-up was 30 months （range, 8-52 months）. We evaluated all of the patients from a clinical standpoint with use of a standard-terminology questionnaire with respect to the short-term curative effects and patients＇ satisfaction. Hip pain status and functional ability were important indicators of treatment efficacy. Results： Harris hip score and patients＇ satisfaction in femoral osteoporosis patients who underwent noncemented hip arthroplasty were lower （P=0.004, P=0.03） while the incidence of thigh pain was higher （P=0.03） than the patients with non-osteoporosis. Conclusion： The higher incidence of pain, as well as the decrease in function experienced by the patients in osteoporosis group, supports the case that cementless arthroplasty is not a better choice for those patients and that we had better select prosthesis based on the femoral metaphyseal BMD.  相似文献   

6.
Objective: To assess the occurrence of stressful life events in the year before the initiation of systemic sclerosis. Methods: A consecutive series of 40 patients with systemic sclerosis (mean age (56.3~ 11.9) years, mean disease duration (4.3±3.1) years; 32 females and 8 males), including 28 with diffuse cutaneous scleroderma and 12 with limited cutaneous scleroderma, were evaluated. A control group of 40 healthy subjects free of systemic sclerosis also was included. Socioeconomic status was inves-tigated and Paykel's interview for recent life events (a semi-structured research interview covering 64 life events) was conducted. Results: Patients with systemic sclerosis showed higher percentages of lower education (72.5%) and working class (82.5%), and reported more stressful life events (P＜0.05), such as exits (P＜0.05), undesirable events (P＜0.01), and uncontrolled events (P＜0.001), when compared with the control. More events that had an objective negative impact (P＜0.001) were also reported in systemic sclerosis patients than in the control. These results are in accordance with a muitifactorial model of pathogenesis in systemic sclerosis. Conclusion: We reported a strong relationship between stressful life events and the initiation of systemic sclerosis. Our findings are consistent with current understanding of the extensive links of behavioral responses to stress with neurophysiological and biochemical processes.  相似文献   

7.
Coronavirus disease 2019 (Covid-19) created unparalleled challenges to anatomy education. Gross anatomy education has been particularly impacted given the traditional in-person format of didactic instruction and/or laboratory component(s). To assess the changes in gross anatomy lecture and laboratory instruction, assessment, and teaching resources utilized as a result of Covid-19, a survey was distributed to gross anatomy educators through professional associations and listservs. Of the 67 survey responses received for the May–August 2020 academic period, 84% were from United States (US) institutions, while 16% were internationally based. Respondents indicated that in-person lecture decreased during Covid-19 (before: 76%, during: 8%, P < 0.001) and use of cadaver materials declined (before: 76 ± 33%, during: 34 ± 43%, P < 0.001). The use of cadaver materials in laboratories decreased during Covid-19 across academic programs, stand-alone and integrated anatomy courses, and private and public institutions (P ≤ 0.004). Before Covid-19, cadaveric materials used in laboratories were greater among professional health programs relative to medical and undergraduate programs (P ≤ 0.03) and among stand-alone relative to integrated anatomy courses (P ≤ 0.03). Furthermore, computer-based assessment increased (P < 0.001) and assessment materials changed from cadaveric material to images (P < 0.03) during Covid-19, even though assessment structure was not different (P > 0.05). The use of digital teaching resources increased during Covid-19 (P < 0.001), with reports of increased use of in-house created content, BlueLink, and Complete Anatomy software (P < 0.05). While primarily representing US institutions, this study provided evidence of how anatomy educators adapted their courses, largely through virtual mediums, and modified laboratory protocols during the initial emergence of the Covid-19 pandemic.  相似文献   

8.
Objective: To demonstrate the validity and reliability of volumetric quantitative computed tomography (vQCT) with multi-slice computed tomography (MSCT) and dual energy X-ray absorptiometry (DXA) for hip bone mineral density (BMD) measurements, and to compare the differences between the two techniques in discriminating postmenopausal women with osteoporosis-related vertebral fractures from those without. Methods: Ninety subjects were enrolled and divided into three groups based on the BMD values of the lumbar spine and/or the femoral neck by DXA. Groups 1 and 2 consisted of postmenopausal women with BMD changes ＜-2SD, with and without radiographically confirmed vertebral fracture (n=11 and 33, respectively).Group 3 comprised normal controls with BMD changes ≥-1SD (n=46). Post-MSCT (GE, LightSpeed16) scan reconstructed images of the abdominal-pelvic region, 1.25 mm thick per slice, were processed by OsteoCAD software to calculate the following parameters: volumetric BMD values of trabecular bone (TRAB), cortical bone (CORT), and integral bone (INTGL) of the left femoral neck, femoral neck axis length (NAL), and minimum cross-section area (mCSA). DXA BMD measurements of the lumbar spine (AP-SPINE) and the left femoral neck (NECK) also were performed for each subject. Results: The values of all seven parameters were significantly lower in subjects of Groups 1 and 2 than in normal postmenopausal women (P＜0.05, respectively).Comparing Groups 1 and 2, 3D-TRAB and 3D-INTGL were significantly lower in postmenopausal women with vertebral fracture(s) [(109.8±9.61) and (243.3±33.0) mg/cm3, respectively] than in those without [(148.9±7.47) and (285.4±17.8) mg/cm3,respectively] (P＜0.05, respectively), but no significant differences were evident in AP-SPINE or NECK BMD. Conclusion: the femoral neck-derived volumetric BMD parameters using vQCT appeared better than the DXA-derived ones in discriminating osteoporotic postmenopausal women with vertebral fractures from those without, vQCT might be useful to evaluate the effect of osteoporotic vertebral fracture status on changes in bone mass in the femoral neck.  相似文献   

9.
Objective： The aim of this study was to investigate subgingival infection frequencies ofPorphyromonas gingivalis and Actinobacillus actinomycetemcomitans strains with genetic variation in Chinese chronic periodontitis （CP） patients and to evaluate its correlation with clinical parameters. Methods： Two multiplex polymerase chain reaction （PCR） assays were developed to detect the 16SrDNA, collagenase （prtC） and fimbria （fimA） genes of P. gingivalis and the 16SrDNA, leukotoxin （lktA） and fimbria-associated protein （fap） genes ofA. actinomycetemcomitans in 60 sulcus samples from 30 periodontal healthy subjects and in 122 subgingival plaque samples from 61 patients with CP. The PCR products were further T-A cloned and sent for nucleotide sequence analysis. Results： The 16SrDNA,prtC andfimA genes ofP. gingivalis were detected in 92.6%, 85.2% and 80.3% of the subgingival plaque samples respectively, while the 16SrDNA, lktA andfap genes ofA. actinomycetemcomitans were in 84.4%, 75.4% and 50.0% respectively. Nucleotide sequence analysis showed 98.62%-100% homology of the PCR products in these genes with the reported sequences. P. gingivalis strains with prtC＋/fimA＋ and A. actinomycetemcomitans with lktA＋ were predominant in deep pockets （〉6 mm） or in sites with attachment loss 〉5 mm than in shallow pockets （3-4 mm） or in sites with attachment loss 〈2 mm （P〈0.05）. P. gingivalis strains withprtC＋/fimA＋ also showed higher frequency in gingival index （GI）=3 than in GI=1 group （P〈0.05）. Conclusion： Infection ofP. gingivalis with prtC＋/fimA＋ and A. actinomycetemcomitans with lktA＋ correlates with periodontal destruction of CP in Chinese. Nonetheless P. gingivalis fim4, prtC genes and A. actinomycetem- comitans lktA gene are closely associated with periodontal destruction, while A. actinomycetemcomitansfap gene is not.  相似文献   

10.
Cadaver-specific postmortem computed tomography (PMCT) has become an integral part in anatomy teaching at several universities. Recently, the feasibility of contrast-enhanced (CE)-PMCT has been demonstrated. The purpose of this study was to identify particular strengths and weaknesses of both non-enhanced and contrast-enhanced PMCT compared to conventional cadaver dissection. First, the students’ perception of the learning effectiveness of the three different modalities have been assessed using a 34-item survey (five-point Likert scale) covering all anatomy course modules. Results were compared using the nonparametric Friedman Test. Second, the most frequent artifacts in cadaver CT scans, were systematically analyzed in 122 PMCT and 31 CE-PMCT data sets to quantify method-related limitations and characteristics. Perfusion quality was assessed in 57 vascular segments (38 arterial and 19 venous). The survey was answered by n = 257/320 (80.3%) students. Increased learning benefits of PMCT/ CE-PMCT compared to cadaver dissection were found in osteology (2/3 categories, P < 0.001), head and neck (2/5 categories, P < 0.01), and brain anatomy (3/3 categories, P < 0.01). Contrast-enhanced-PMCT was perceived particularly useful in learning vascular anatomy (10/10 categories, P < 0.01). Cadaver dissection received significantly higher scores compared to PMCT and CE-PMCT in all categories of the abdomen and thorax (7/7 categories, P < 0.001), as well as the majority of muscular anatomy (5/6 categories, P < 0.001). Frequent postmortem artifacts (total n = 28, native-phase n = 21, contrast injection-related n = 7) were identified and assessed. The results of this work contribute to the understanding of the value of integrating cadaver-specific PMCT in anatomy teaching.  相似文献   

11.
This study assessed the effect of the course cycle on theoretical knowledge of dental morphology and the dental carving ability of dental students. Thirty-two dental students from the third semester (initial cycle) and 30 students from the eighth and tenth semesters of the dental course (end cycle) had their theoretical knowledge on dental morphology assessed using a questionnaire with ten closed questions. Their dental carving ability was also assessed using wax carvings in macro models of plaster (for the third [S3] and eight [S8] semesters) and natural-sized artificial teeth (for the tenth [S10] semester). The teeth chosen for the dental carving activity were #16 and #47. The scores were statistically analyzed using the t-test, Kruskal–Wallis test, and Mann–Whitney test (α = 0.05). Students from the initial cycle presented better theoretical knowledge than the other groups did (P < 0.007). No significant differences in carving score were found between the initial and end cycles (P > 0.05), although S10 students obtained a higher score for teeth #16 and #47 (P < 0.05). Natural-sized artificial teeth received a higher evaluation score in dental carvings than the macro models (P < 0.001). Within the limits of this study, it was possible to conclude that students from the initial cycle (S3) presented higher theoretical knowledge, whereas no difference in carving ability was observed between the initial and end cycles. The tenth semester (S10) students performed dental carvings with better quality. Furthermore, carvings in natural-sized artificial teeth presented better quality compared with the macro models.  相似文献   

12.
INTRODUCTION Telomeres are distinctive DNA-protein struc-tures that cap the ends of linear chromosomes.It is very important to keep the chromosomes stabilization.Telomerase activity is closely linked to attainment of cellular immortality,a step in carcinogenesis,while lack of such activity contributes to cellular senes-cence.Telomerase is activated in more than85%ofmalignant tumors(Hiayma et al.,1997).Human te-lomeric repeat binding factor1(TRF1)is a telomere associated with proteins a…  相似文献   

13.
Objective: To observe the effect of Yangxueqingnao particles on rat vascular smooth muscle cell (VSMC) proliferation induced by lysophosphatidic acid (LPA). Methods: The amount of3H-TdR (3H-thymidine) admixed in cultured rat VSMC was measured and mitogen-activated protein kinase (MAPK) activity and lipid peroxidation end product malondialdehyde (MDA) content of the VSMC were assayed. Results: 1×10−9, 1×10−8, 1×10−7 mol/L LPA in a concentration dependent manner, induced the amount of3H-TdR admixed, MAP kinase activity, and MDA content of the cultured rat VSMC to increase. However, 5%, 10%, and 15% Yangxueqingnao serum preincubation resulted in a decrease of 23.0%, 42.0%, and 52.0% (P<0.01) respectively in the amount of3H-TdR admixed, a decline in VSMC MAP kinase activity of 13.9% (P<0.05), 29.6% (P<0.01), and 48.9% (P<0.01) respectively, and also, a decrease in MDA content of VSMC of 19.4%, 24.7%, and 43.2% (P<0.01) respectively, in the 1×10−7 mol/L LPA-treated VSMC. Conclusions: LPA activates the proliferation and lipid peroxidation of VSMC in a concentration dependent manner. The LPA-induced VSMC proliferation is related to the activity of MAP kinases, enzymes involved in an intracellular signalling pathway. The results of the present study showed that Yangxueqingnao particles can effectively inhibit LPA-induced VSMC proliferation, MAP kinase activation, and reduce lipid peroxidative lesion. Project (No. 491010-W50339) supported by Chinese Traditional Medicine Administration Bureau of Zhejiang Province, China  相似文献   

14.
The effects of dietary supplementation with Clostridium butyricum on growth performance and humoral immune response in Miichthys miiuy were evaluated. One hundred and fifty Miichthys miiuy weighing approximately 200-260 g were divided into five groups and reared in 15 tanks with closed circuiting culture system. The animals were fed 5 diets： basal diet only （control） or supplemented of the basal diet with C. butyricum at doses of 10^3 （CB1）, 10^5 （CB2）, 10^7 （CB3） or 10^9 （CB4） CFU/g. Compared with the control, the serum phenoloxidase activity was significantly increased by the supplementation （P〈0.05）, acid phosphatases activity was increased significantly （P〈0.05） at the doses of 10^9 CFU/g. Serum lysozyme activity peaked at dose of 10^7 CFU/g and in the skin mucus at dose of 10^9 CFU/g. Immunoglobulin M level in the serum and skin mucus was increased except at dose of 10^3 CFU/g （P〈0.05）. The growth at the dose of 10^9 CFU/g was higher than that of the control （P〈0.05）. It is concluded that supplementation of C. butyricum can mediate the humoral immune responses and improve the growth performance in Miichthys miiuy.  相似文献   

15.
Objective: To evaluate clinical, Quality of Life (QoL) and medical cost outcomes in patients with symptomatic reflux esophagitis (RE) receiving different ″triple combination therapy″. Methods: A multicenter medical effectiveness trial conducted in 10 hospitals of 5 regions in Zhejiang Province. 248 patient-volunteers were assigned to 8 weeks of ″ triple combination therapy″ with Lansoprazole plus Cisapride and Sucralfate or Ranitidine plus Cisapride and Sucralfate. Main outcomes assessment included symptoms scale scores, RE severity, QoL at baseline and 8 weeks. Medical cost data were collected with cost analysis questionnaire. Results: (1)More Lansoprazole group patients noted RE symptoms resolution than Ranitidine group(92.3% vs 78.4%, P<0.01). There was no striking difference between two groups in RE healing rate (90.8% vs 82.9%, P>0.05). (2)RE significantly impaired QoL of patients(P<0.001).Compared with Ranitidine group, QoL in Lansoprazole group had significant improvement (rate of ″good″ QoL 64.5% vs 45.6%, P<0.01). (3)There was close correlation between symptomic effectiveness and QoL rating scale in both the Lansoprazole and Ranitidine group(P<0.01, r=0.235 and 0.353 respectively). There were no statistical difference of medical cost between the two groups (P>0.05). Conclusion: RE significantly impaired QoL of patients. ″Triple combination therapies″ can significantly improve RE symptoms and QoL. Lansoprazole combination therapy was more cost-effective than Ranitidine combination group.  相似文献   

16.
Objective: To investigate the influence of lead exposure on the immune function of lymphocytes and erythrocytes in preschool children. Materials and methods: A group of 217 children three to six years of age from a rural area were given a thorough physical examination and the concentration of lead in blood samples taken from each subject was determined. The indices of lymphocyte immunity (CD 3CD 4, CD 3CD 8, CD 4CD 8, CD-3CD 19) and erythrocyte immunity (RBC-C3b, RBC-IC, RFER, RFIR, CD35 and its average fluorescence intensity) of 40 children with blood lead levels above 0.483 μmol/L were measured and compared with a control group. Results: The blood lead levels of the 217 children ranged from 0.11 μmol/L to 2.11 μmol/L. The CD 3CD 4and CD 4CD 8 cells were lower (P＜0.01) and the CD 3CD 8 cells were higher in the lead-poisoned subjects than those in the control group (P＜0.05). CD 3 and CD-3CD 19 did not show significant differences. Although the RBC-C3b rosette forming rate was lower and the RBC-IC rosette forming rate was higher in the lead-poisoned group, this difference could not be shown to be statistically significant (P＞0.05). RFIR was found to be lower in the lead-poisoned group (P＜0.01). Compared with the control group, the positive rate of CD35 was not found to be significantly different in a group of 25 lead-poisoned children (P＞0.05), while the average fluorescence intensity was lower in the lead-poisoned group (P＜0.05). Conclusion: Lead exposure can result in impaired immune function of T lymphocytes and erythrocytes in preschool children.  相似文献   

17.
1　Ｉｎｔｒｏｄｕｃｔｉｏｎ　Ｔｈｅｆｕｎｄａｍｅｎｔａｌｐｈｙｓｉｃａｌｍｅｔａｌｌｕｒｇｙｏｆｔｈｅｒｍｏｍｅｃｈａｎｉｃａｌｐｒｏｃｅｓｓｉｎｇ(ＴＭＰ)ｈａｓｂｅｃｏｍｅｍｕｃｈｂｅｔｔｅｒｕｎｄｅｒｓｔｏｏｄｏｖｅｒｔｈｅｌａｓｔｔｗｏｄｅｃａｄｅｓ[1～8].ＩｔｉｓｗｅｌｌｃｏｍｍｏｎｌｙｒｅｃｏｇｎｉｚｅｄｔｈａｔｔｈｅｍｉｎｕｔｅａｄｄｉｔｉｏｎｏｆｓｔｒｏｎｇｃａｒｂｏｎｉｔｒｉｄｅｏｒｎｉｔｒｉｄｅｆｏｒｍｉｎｇｅｌｅｍｅｎｔｓｓｕｃｈａｓＮｂ,ＴｉａｎｄＶｔａｋｅｓｖｅｒｙｉｍｐ…  相似文献   

18.
This study presents a rapid, specific and sensitive liquid chromatography/tandem mass spectrometry (LC-MS/MS) assay for determination of risperidone (RIS) in human serum using paroxetine as an internal standard (IS). An Alltima-C 18separation. The analysis was performed by selected reaction monitoring (SRM) method, and the peak area of the m/z 411.3→ 191.1 transition for RIS was measured versus that of the m/z 330.1→192.1 transition for IS to generate the standard curves. The assay linearity of RIS was confirmed over the range 0.25～50.00 ng/ml and the limit of quantitation was 0.05 ng/ml. The linear range corresponds well with the serum concentrations of the analytes obtained in clinical pharmacokinetic studies. Intraday and interday relative standard deviations were 1.85%～9.09% and 1.56%～4.38%, respectively. The recovery of RIS from serum was in the range of 70.20%～84.50%. The method was successfully applied to investigate the bioequivalence between two kinds of tablets (test versus reference products) in 18 healthy male Chinese volunteers. The result suggests that two formulations are bioequivalent.  相似文献   

19.
E-learning is an educational method that improves knowledge innovation by sharing relevant images for advanced learning, especially in a pandemic state. Furthermore, cone-beam computed tomography (CBCT) is a method that gathers medical or dental diagnostic images. This study aimed to analyze the effectiveness of dental anatomy education through a CBCT technology tool, through teachers' and students' perspectives, adjusted according to the disruptions caused by the Covid-19 pandemic. A cohort study and longitudinal exploratory analysis were performed. Forty undergraduate first-year dental students, from the University of Coimbra in Portugal, were selected as per the inclusion and exclusion criteria. Two different teaching methods were applied during an identical time-period: face-to-face lectures complemented by physical models (T1 cohort) and webinar lectures complemented by CBCT images (T2 cohort). Learning outcomes were then studied according to theoretical and spatial orientation contexts. A self-reported survey that focused on students' satisfaction, stress, and support was studied. Both teaching methods were analyzed with paired sample student's t-test and Pearson Correlation Confidence intervals 95% with P < 0.05. Furthermore, exploratory factor analysis (EFA) was used for self-reported satisfaction survey validity and reliability analysis. The learning outcomes between T1 and T2 cohorts were statistically significant, (P < 0.001) corresponding to differences with a large effect degree (r > 0.60). Students' satisfaction, as measured on a six-point Likert scale, was positively influenced by the webinar lectures supplemented with CBCT images (T2 cohort) in a learning context (4.95 ± 0.5) and future applications (5.92 ± 0.27). In conclusion, the webinar approach with CBCT images was more effective and better learning method for teaching dental anatomy.  相似文献   

20.
The presentation of pre-sliced specimens is a frequently used method in the laboratory teaching of cross-sectional anatomy. In the present study, a new teaching method based on a hands-on slicing activity was introduced into the teaching of brain, heart, and liver cross-sectional anatomy. A randomized, controlled trial was performed. A total of 182 third-year medical students were randomized into a control group taught with the prosection mode (pre-sliced organ viewing) and an experimental group taught with the dissection mode (hands-on organ slicing). These teaching methods were assessed by testing the students' knowledge of cross-sectional specimens and cross-sectional radiological images, and analyzing students' feedback. Using a specimen test on three organs (brain, heart, and liver), significant differences were observed in the mean scores of the control and experimental groups: for brain 59.6% (±14.2) vs. 70.1% (±15.5), (P < 0.001, Cohen's d = 0.17); for heart: 57.6% (±12.5) vs. 75.6% (±15.3), (P < 0.001, d = 0.30); and for liver: 60.4% (±14.5) vs. 81.7% (±14.2), (P < 0.001, d = 0.46). In a cross-sectional radiological image test, better performance was also found in the experimental group (P < 0.001). The mean scores of the control vs. experimental groups were as follows: for brain imaging 63.9% (±15.1) vs. 71.1% (±16.1); for heart imaging 64.7% (±14.5) vs. 75.2% (±15.5); and for liver imaging 61.1% (±15.5) vs. 81.2% (±14.6), respectively. The effect sizes (Cohen's d) were 0.05, 0.23, and 0.52, respectively. Students in the lower tertile benefited the most from the slicing experiences. Students' feedback was generally positive. Hands-on slicing activity can increase the effectiveness of anatomy teaching and increase students' ability to interpret radiological images.  相似文献   

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