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1.
ＩＮＴＲＯＤＵＣＴＩＯＮＴｅｓｔｏｓｔｅｒｏｎｅｉｓａｐｒｉｍａｒｙｈｏｒｍｏｎｅｉｎｍｅｎａｎｄａｓｓｏｃｉａｔｅｄｗｉｔｈｓｐｅｒｍａｔｏｇｅｎｅｓｉｓａｎｄｓｐｅｒｍｍａｔｕｒａｔｉｏｎ (Ｓｔｅｉｎｂｅｒｇｅｒｅｔａｌ.,1 973 ;Ｍａｒｓｈａｌｌｅｔａ  相似文献   

2.
观察血清基质金属蛋白酶-9（MMP-9）及血管内皮生长因子（VEGF）在实验性新西兰白兔蛛网膜下腔出血后的浓度变化,探讨它们与脑血管痉挛发生、发展及转归过程的关系,为临床诊断及治疗提供理论依据。实验结果表明血清MMP-9及VEGF的浓度变化可以作为预测蛛网膜下腔出血后脑血管痉挛的发作、判断其发展及预后的参考指标之一,为临床诊断与治疗提供依据。MMP-9及VEGF参与了蛛网膜下腔出血后的病理生理过程,与迟发性脑血管痉挛的发病机制有密切关系。  相似文献   

3.
目的:了解原发性低钾型周期性麻痹患者血清肌酶学的异常改变及其规律.方法:回顾性分析42例原发性低钾型周期性麻痹患者的临床资料,探讨其血清肌酶学的异常改变及规律.结果:原发性低钾型周期性麻痹患者肌酶学各项指标普遍有不同程度升高,其中肌酸激酶(CK)升高最为突出.肌酶改变呈现一定规律.结论:血清肌酶学各项指标普遍升高且呈一定规律性,是原发性低钾型周期性麻痹的临床特征的重要组成部份.  相似文献   

4.
Study on the neurotoxic effects of low-level lead exposure in rats   总被引：10，自引：0，他引：10  
Objective: To investigate effects of developmental lead exposure on nitric oxide synthase (NOS) activity in different brain regions and on N-methyl-D-aspartate (NMDA) receptor mRNA expression in the hippocampus of rats. On the basis of these observations, we explored possible mechanisms by which lead exposure leads to impaired learning and memorizing abilities in children. Methods: A series of rat animal models exposed to low levels of lead during the developing period was established (drinking water containing 0.025%, 0.05% and 0.075% lead acetate). NOS activities in the hippocampus, the cerebral cortex, the cerebellum and the brain stem were determined with fluorescence measurement and levels of mRNA expression of the NMDA receptor 2A (NR2A) subunit and NMDA receptor 2B (NR2B) subunit in the rat hippocampus were measured with Retro-translation (RT-PCR). Results: There were no differences in the body weight of rat pups between any of the groups at any given time (P>0.05). The blood lead level of Pb-exposed rat pups showed a systematic pattern of change: at 14 d of age, it was lower than that at 7 d of age, then rising to the peak level at 21 d and finally falling to lower levels at 28 d. The hippocampal NOS activities of lead-exposed groups were all lower than that of the control group on the 21st and 28th day (P<0.01). NOS activities in the cerebellum of lead-exposed groups were all lower than that of the control group on the 21st and 28th day (P<0.001) and the NOS activity of the 0.025% group was significantly lower than that of the 0.05% and 0.075% groups on the 28th day (P<0.05). NOS activity in the cerebral cortex of the 0.075% group was significantly lower than that of the control, 0.025% and 0.05% groups on the four day spans (P<0.001). There was no significant difference of NOS activity in the brain stem between any lead-exposed group and the control group on the four day spans. In the 0.05% and the 0.075% groups, the level of NR2A mRNA expression was higher than that in the control group at 7 d and 14 d of age (P<0.05). In the 0.025% group, the level of NR2A was found to be higher than that in the control group at 7 d of age only (P<0.05). No significant differences were found for the levels of NR2B mRNA expression between any of the groups at any given time. Conclusions: NOS activity in the hippocampus, the cerebral cortex and the cerebellum are inhibited by lead exposure. The degree of the inhibitory effect depends on the time span of exposure and the lead concentration. Developmental low-level lead exposure was found to raise the level of NR2A mRNA expression in the hippocampus of rats. Developmental low-level lead exposure does not affect the level of NR2B mRNA expression in the hippocampus.  相似文献   

5.
This longitudinal study examined how nightly variations in adolescents’ study and sleep time are associated with academic problems on the following day. Participants (N = 535, 9th grade Mage = 14.88) completed daily diaries every day for 14 days in 9th, 10th, and 12th grades. Results suggest that regardless of how much a student generally studies each day, if that student sacrifices sleep time to study more than usual, he or she will have more trouble understanding material taught in class and be more likely to struggle on an assignment or test the following day. Because students are increasingly likely to sacrifice sleep time for studying in the latter years of high school, this negative dynamic becomes increasingly prevalent over time.  相似文献   

6.
Aphrodisiacs are required to improve male sexual function under stressful conditions. Due to the effects of oxidative stress and dopamine on male sexual function, we hypothesized that Moringa oleifera leaves might improve male sexual dysfunction induced by stress. Therefore, the effects on various factors playing important roles in male sexual behavior, such as antioxidant effects, the suppression of monoamine and phosphodiesterase type 5 (PDE-5) activities, serum testosterone and corticosterone levels, and histomorphological changes in the testes, of a hydroethanolic extract of M. oleifera leaves were investigated. Various doses of extract including 10, 50, and 250 mg/kg body weight (BW) were given orally to male Wistar rats before exposure to 12 h-immobilization stress for 7 d. The results demonstrated that the extract showed both antioxidant and monoamine oxidase type B (MAO-B) suppression activities. At 7 d of treatment, the low dose of extract improved sexual performance in stress-exposed rats by decreasing intromission latency and increasing intromission frequency. It also suppressed PDE-5 activity, decreased serum corticosterone level, but increased serum testosterone, numbers of interstitial cells of Leydig and spermatozoa. The increased numbers of interstitial cells of Leydig and spermatozoa might have been due to the antioxidant effect of the extract. The increased sexual performance during the intromission phase might have been due to the suppression of MAO-B and PDE-5 activities and increased testosterone. Therefore, M. oleifera is a potential aphrodisiac, but further research concerning the precise underlying mechanisms is still needed.  相似文献   

7.
目的:在康脑液方剂干预下观察皮质区内源性神经细胞干细胞因子(SCF)mRNA在大鼠脑缺血再灌注损伤后不同时间的表达情况。方法:成年SD大鼠,以线栓法建立大脑中动脉缺血再灌注模型,随机分为模型组、药物干预组和假手术组。原位杂交技术检测脑缺血1.5h再灌注1～14d后,脑皮质区SCFmRNA表达情况。结果:脑缺血再灌注后,药物干预组、模型组SCFmRNA的表达在皮质区均明显高于假手术组,于第7天达高峰,第14天下降。结论:药物干预后脑缺血再灌注脑皮质区SCFmRNA表达在不同时间点与模型组具备相同的表达规律,两组SCFmRNA的表达无显著性差异。  相似文献   

8.
Objectives: To measure serum and follicular resistin, steroids hormone levels in women with PCOS (polycystic ovary syndrome) (BMI (body mass index)<25 kg/m2), to assess possible correlations of resistin to hormonal and metabolic parameters and to analyze the clinical outcomes of in vitro fertilization-embryo transfer (IVF-ET) in women with PCOS and tubal infertility. Study design: We analyzed the clinical outcomes of IVF-ET in women with PCOS (BMI<25 kg/m2) and tubal infertility during the years 2002 to 2004 and compared the serum and follicular fluid resistin levels, estradiol (E2), progesterone (P), testosterone (T) levels in 20 PCOS and 20 healthy, age-matched women without PCOS during IVF-stimulated cycles. The correlations between the resistin levels and the outcomes of IVF-ET were evaluated. Results: No significant differences in resistin levels of either serum or follicular fluid between PCOS and control group were found. However, resistin levels in serum were higher than that in follicular fluid in both groups. Multiple regression analysis showed that resistin levels in serum did not correlate with BMI, estradiol, LH (luteinizing hormone) and insulin level in fasting blood. No significant correlations were found between follicular fluid reisistin levels and fertilization rate, implantation rate, clinical pregnancy rate or early miscarriage rate in both PCOS and control groups. Conclusion: Our results show that resistin does not have correlation with the hormonal and metabolic parameters as well as the outcomes of IVF. These data suggest that resistin is unlikely to be a local determinant factor in steroidogenesis and growth and maturation of oocytes during IVF-ET in lean women with PCOS.  相似文献   

9.
目的探讨男童血清瘦素水平与肥胖及性发育的关系。方法选择9—14岁符合单纯性肥胖标准的男性患儿34例为肥胖组,健康男性儿童32例为对照组,分别计算体重指数（BMI）、应用放射性免疫法测定血清瘦素（Leptin）水平、化学发光法测定血清雌二醇（E2）及睾酮（T）水平,用游标卡尺测量并计算睾丸体积,应用SPSS16．0软件进行组间t检验比较两组间差异,线性相关分析肥胖男童血清瘦素水平与BMI,E2及T之间的相关性。结果肥胖男童血清瘦素、雌二醇水平及BMI均较对照组儿童高,且差异有统计学意义（P〈0．01）;肥胖男童血清睾酮水平及睾丸体积均较对照组儿童低,且差异有统计学意义（P〈0．01）。肥胖男童血清瘦素水平与BMI呈正相关（r=0．69,P〈0.01）,与雌二醇呈正相关（r=0．381,P〈0.05）,与睾酮呈负相关（r=-0.347,P〈0.05）。结论肥胖男童存在瘦素抵抗现象,且有性发育不良的趋势。  相似文献   

10.
Use and effects of liver specific antigen in orthotopic liver transplantations were researched in this study. Group I: syngeneic control (Wistar-to-Wistar); Group II: acute rejection (SD-to-Wistar); Group III: Thymic inoculation of SD rat LSA day 7 before transplantation. The observation of common situation and survival time, rejection grades, NF-κB activity of splenocytes and IL-2mRNA expression of grafted liver were used to analyze acute rejection severity and immune state of animals in different groups. The common situation of group I was very well after transplantation and no signs of rejection were found. Recipients of group II lost body weight progressively All dead within day 9 to day 13 posttransplantation; median survival time was 10.7 ±0.51 days. It was an optimal acute rejection control. As for group III, 5 out of 6 recipients survived for a long time and common situation was remarkably better than that of group II. Its rejection grades were significantly lower than that of group II(P<0.05). NF-κB activity was only detected in group I at day 5 and day 7 after transplantation, whereas high activity of NF-κB was detected at all time points in groupII and the low NF-κB activity detected in group III was significantly lower than that of group II (P<0.05). No IL-2mRNA expression was detected at any time point in group I, whereas high level expression was detected at all time points in group II and the low level expression only detected at day 3 in group III was significantly lower than that of group II (P<0.05). Conclusion: LSA is an important transplantation antigen which is involved directly in the immunorejection of liver transplantation. We report here for the first time that intrathymic inoculation of LSA can alleviate the rejection of liver allotransplantation; and that grafts can survive for a long time thereby, thus leading to a novel way to achieve liver transplantation immunotolerance. Project (NO. 011106206) supported by the Science and Technology Bureau of Zhejiang Province Foundation  相似文献   

11.
Objective: To observe the difference of androgen and inflammatory cytokines level in atherosclerosis and analyse their relations. Method: Both carotid arteries and arteries of lower extremity were subjected to ultrasonic examination by Doppler's method. Those with much atheromatous plaque formation were ranged into case group, and those with normal result formed control group. Total, free testosterone and estradiol were assayed by radioimmunoassay. C reactive protein (CRP) was assayed by nepheloturbidity. Tumor necrosis factor-α (TNF-α), Interleukin-6 (IL-6), Interleukin-8 (IL-8), Interleukin-10 (IL-10), Interleukin-18 (IL-18), soluble intercellular adhesion molecule-1 (sICAM-1) and soluble vascular cell adhesion molecule-1 (sVCAM-1) were assayed by ELISA. The mean difference between two groups and the correlation between free testosterone and cytokines were analysed. Results: Free testosterone was (6.337±3.371) pg/L in case group and (11.375±4.733) pg/L in control group,P<0.01. No differences were found in total testosterone and estradiol. CRP was (27.294±10.238) mg/L in case group and (12.843±6.318) mg/L in control group,P<0.01. IL-6 was (41.700±31.385) pg/L in case group and (25.396±20.772) pg/L in control group,P<0.05. IL-8 was (89.249±58.357) pg/L in case group and (67.873±31.227) pg/L in control group,P<0.05. sICAM-1 was (470.491±134.078) pg/L in case group and (368.487±97.183) pg/L in control group,P<0.01.sVCAM-1 was (537.808±213.172) pg/L in case group and (457.275±157.273) pg/L in control group,P<0.05. There were no differences in TNF-α, IL-10 and IL-18. Correlation analysis showed that FT (free testosterone) had negative correlation with CRP, IL-6 and sICAM-1. Among them FT had well correlation with CRP, correlation index was −0.678. Conclusion: Free testosterone was in negative correlation with atherosclerosis in old-age male. Free testosterone may have the role of anti-atherosclerosis, and this effect was not achieved by its transformation to estradiol. Low free testosterone level was followed by increased level of inflammatory cytokines. Low free testosterones coexist with inflammation and they both affect the process of atherosclerosis in old-age male. Project (No. 2003B045) supported by the Health Bureau of Zhejiang Province, China  相似文献   

12.
The purpose of this study was, first, to understand the item hierarchy regarding students’ understanding of scientific models and modeling (USM). Secondly, this study investigated Taiwanese students’ USM progression from 7th to 12th grade, and after participating in a model-based curriculum. The questionnaire items were developed based on 6 aspects of USM, namely, model type, model content, constructed nature of models, multiple models, change of models, and purpose of models. Moreover, 10 representations of models were included for surveying what a model is. Results show that the purpose of models and model type items covered a wide range of item difficulties. At the one end, items for the purpose of models are most likely to be endorsed by the students, except for the item “models are used to predict.” At the other end, the “model type” items tended to be difficult. The students were least likely to agree that models can be text, mathematical, or dynamic. The items of the constructed nature of models were consistently located above the average, while the change of models items were consistently located around the mean level of difficulty. In terms of the natural progression of USM, the results show significant differences between 7th grade and all grades above 10th, and between 8th grade and 12th grade. The students in the 7th grade intervention group performed better than the students in the 7th and 8th grades who received no special instruction on models.  相似文献   

13.
The effects ofpolychlorinated biphenyls (PCBs) on reproduction of adult cocks were studied by gavaging peanut oil or PCBs (Aroclor 1254, 50 mg/kg) once a week for six consecutive weeks. Physiological parameters were recorded and gonads were removed at the end of experiment for histological examination. The results showed that there was no significant difference between the control and treatment group in body weight, respiration rate, heart rate, body temperature, and the numbers of red and white blood cells. However, there was a marked decrease in the testicular weight and serum testosterone level after PCB treatment. Morphological studies manifested severe damage of the seminiferous tubules by PCB. The number of the germ cells at the different developmental stages was decreased and condensed nuclei were observed in most of these cells. This study revealed that the reproductive function of the adult cocks is sensitive to PCBs, which inhibited mainly spermatogenesis and testosterone secretion.  相似文献   

14.
INTRODUCTION Polychlorinated biphenyls (PCBs) are members of the halogenated hydrocarbon class of lipophilic environmental endocrine disrupters that includes the dibenzofurans and dioxins. Their appearance in the ecosystem and in the tissues from wildlife, as well as documented cases of accidental poisoning led to the banning of their manufacture in 1977 (Tilson and Kodavanti, 1997). The PCBs continue to be of concern to biologists due to reports that exposure to relatively low levels…  相似文献   

15.
Background: Allogeneic blood transfusion-induced immunomodulation (TRIM) and its adverse effect on the prognosis of patients treated surgically for cancer remain complex and controversial. However, the potential risk associated with allogeneic blood transfusion has heightened interest in the use of autologous blood transfusion. In the present study, the serum concentrations of neopterin, interferon-gamma (IFN-γ), T lymphocyte subsets (CD3 , CD4 , CD8 , CD4 /CD8 ) and a possible association between these variables were investigated. The purpose was to further evaluate the effect of autologous versus allogeneic blood transfusion on immunological status in patients undergoing surgery for gastric cancer. Methods: Sixty ASA I～II (American Society of Anesthesiologists) patients undergoing elective radical resection for stomach cancer were randomly allocated to receive either allogeneic blood transfusion (n=30) or autologous blood transfusion (n=30). Serum concentrations of the neopterin, IFN-γ and T lymphocyte subsets in the recipients were measured before induction of anesthesia, after operation, and on the 5th postoperative day. Results: Both two groups, serum neopterin, IFN-γ, percentages of T-cell subsets (CD3 , CD4 ), and CD4 /CD8 ratio had significantly decreased after operation, but decreased more significantly in group H (receiving allogeneic blood transfusion) than those in group A (receiving autologous whole blood transfusion) (P<0.05). On the 5th postoperative day, serum neopterin, IFN-γ, CD3 , CD4 T-cells, and CD4 /CD8 ratio returned to the baseline values in group A. In contrast, the above remain decreasing in group H, where there were no significant relations between serum neopterin and IFN-γ. Conclusion: Perioperative surgical trauma and stress have an immunosuppressive impact on gastric cancer patients. Allogeneic blood transfusion exacerbates the impaired immune response. Autologous blood transfusion might be significantly beneficial for immune-compromised patients in the perioperative period, clearly showing its superiority over allogeneic blood transfusion.  相似文献   

16.
As discourse in sexual education classes across the USA in 1996 began to change, media outlets became important sources of education for teenage girls. Unaffected directly by government policy, one of the most popular teenage girls' magazines, Seventeen, provided a plethora of information on sex. Several scholars have examined teenage magazines' sexual discourse, yet few have assessed the accuracy of sexual health information during a time period when the US Federal Government instituted an abstinence-only curriculum policy for public schools. In addition, there is a gap in the literature regarding magazines' attitudes about teenage abstinence, or lack thereof, especially in a time when politics had taken a very conservative stance on the issue. This paper examines Seventeen magazine between 1996 and 1998 to explore the magazine's attitude towards teen sex and abstinence and to analyse the accuracy of sexual health messages surrounding topics such as abortion, contraception and STDs.  相似文献   

17.
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   

18.
This paper presents the explosion cratering effects and their propagation laws of blast waves in dry standard sands using a 450 g-t geotechnical centrifuge apparatus. Ten centrifuge model tests were completed with various ranges of explosive mass, burial depth and centrifuge accelerations. Eleven accelerometers were installed to record the acceleration response in sand. The dimensions of the explosion craters were measured after the tests. The results demonstrated that the relationship between the dimensionless parameters of cratering efficiency and gravity scaled yield is a power regression function. Three specific function equations were obtained. The results are in general agreement with those obtained by other studies. A scaling law based on the combination of the π terms was used to fit the results of the ten model tests with a correlation coefficient of 0.931. The relationship can be conveniently used to predict the cratering effects in sand. The results also showed that the peak acceleration is a power increasing function of the acceleration level. An empirical exponent relation between the proportional peak acceleration and distance is proposed. The propagation velocity of blast waves is found to be ranged between 200 and 714 m/s.  相似文献   

19.
目的：探讨不同止血方法对腹腔镜卵巢囊肿剔除术后年轻患者卵巢储备功能的影响。方法：将2009年12月至2011年12月因单侧良性卵巢囊肿且年龄≤35岁的住院患者83例随机分为缝合组与电凝组．两组分别于术前、术后,1、6个月后第一次月经的第2-5天检测血清雌二醇（E：）、卵泡刺激素（FSH）及黄体生成素（LH）水平;阴道彩超检测窦卵泡数（AFC）和卵巢间质动脉血流的收缩期峰值（PSV）;以两者结合判定卵巢储备功能。结果：术前激素水平两组间差异无统计学意义（P〉0．05）;术后1、6个月E2、FSH水平与术前比较,缝合组无差异（P〉0．05）、电凝组有差异（P〈0．05）、两组间比较有统计学意义（P〈0．05）,LH水平差异无统计学意义（P〉0．05）;术后1、6个月AFC、PSV水平差异与术前比较,缝合组组内、组间均无统计学意义（P〉0．05）,电凝组组内、组间均有统计学意义;术后共发生卵巢储备功能下降者缝合组10．8％,电凝组15.2％。结论：腹腔镜下卵巢囊肿剔除术两种止血方法对卵巢储备功能均有影响,电凝止血法较单纯缝合止血法所致卵巢储备功能下降更加明显。  相似文献   

20.
银杏叶愈伤组织增殖过程中生理生化特性的研究   总被引：2，自引：0，他引：2  
本文系统研究了银杏叶愈伤组织培养细胞的生长周期,并对培养过程中细胞内的可溶性蛋白的含量,过氧化物酶、苯丙氨酸解氨酶活性的变化以及银杏总黄酮的含量进行了测定,以期为银杏细胞的大规模培养积累数据。  相似文献   

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