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排序方式: 共有290条查询结果,搜索用时 31 毫秒
231.
B. K. Jain Daljit Singh Harmesh Singh A. P. S. Narang Praveen C. Sobti Ajay Gupta 《Indian journal of clinical biochemistry : IJCB》2000,15(1):36-39
Serum total and ionised calcium levels were measured at birth and at 48 hours in 25 term neonates with birth asphyxia (one
minute APGAR score of 6 or less) and in 25 normal term neonates (one minute APGAR score of 7 or more). Infants were categorised
into two groups TAGA (term appropriate for gestational age) and TSGA (term small for gestational age). Asphyxiated infants
had significantly lower serum total and ionised calcium values at birth as well as at 48 hours. Abnormal clinical features
were observed in 48% of asphyxiated infants. Low ionised calcium was detected in symptomatic babies, who had otherwise normal
total calcium values. Due to hyocalcemia especially ionised calcium in asphyxiated infants and high frequency of functional
derangement associated with this hypocalcemioa, serial monitoring of serum isonised calcium levels is necessary. 相似文献
232.
233.
Moushumi Lodh Binita Goswami Nikhil Gupta Surajeet K. Patra Alpana Saxena 《Indian journal of clinical biochemistry : IJCB》2012,27(4):410-413
Multiple myeloma is a disseminated malignancy of monoclonal plasma cells that accounts for 15 % of all hematological cancers. The present study was conducted to evaluate the role of inflammation and oxidant-antioxidant dynamics in the etiology of this disease. The study population comprised of 20 cases of multiple myeloma and 20 healthy controls. The parameters evaluated were serum malondialdehyde (MDA), superoxide dismutase (SOD) and ferritin levels. The serum MDA levels were 1.9 ± 0.96 nmol/ml in cases as compared to 0.98 ± 0.55 nmol/ml in the controls. Similarly, a statistically significant difference was noted in the SOD and ferritin levels between the cases and controls (93.2 ± 23.8 vs. 210.1 ± 190.5 U/ml and 285.8 ± 216.4 vs. 131.8 ± 30.1 ng/ml respectively). Our study highlights the imbalance in the oxidant-anti oxidant mechanism and the role of smoldering inflammation in the etiology of multiple myeloma. 相似文献
234.
Vishal Gupta Insiya Jafferji Miguel Garza Vladislava O. Melnikova David K. Hasegawa Ronald Pethig Darren W. Davis 《Biomicrofluidics》2012,6(2)
Isolation and enumeration of circulating tumor cells (CTCs) are used to monitor metastatic disease progression and guide cancer therapy. However, currently available technologies are limited to cells expressing specific cell surface markers, such as epithelial cell adhesion molecule (EpCAM) or have limited specificity because they are based on cell size alone. We developed a device, ApoStream™ that overcomes these limitations by exploiting differences in the biophysical characteristics between cancer cells and normal, healthy blood cells to capture CTCs using dielectrophoretic technology in a microfluidic flow chamber. Further, the system overcomes throughput limitations by operating in continuous mode for efficient isolation and enrichment of CTCs from blood. The performance of the device was optimized using a design of experiment approach for key operating parameters such as frequency, voltage and flow rates, and buffer formulations. Cell spiking studies were conducted using SKOV3 or MDA-MB-231 cell lines that have a high and low expression level of EpCAM, respectively, to demonstrate linearity and precision of recovery independent of EpCAM receptor levels. The average recovery of SKOV3 and MDA-MB-231 cancer cells spiked into approximately 12 × 106 peripheral blood mononuclear cells obtained from 7.5 ml normal human donor blood was 75.4% ± 3.1% (n = 12) and 71.2% ± 1.6% (n = 6), respectively. The intra-day and inter-day precision coefficients of variation of the device were both less than 3%. Linear regression analysis yielded a correlation coefficient (R2) of more than 0.99 for a spiking range of 4–2600 cells. The viability of MDA-MB-231 cancer cells captured with ApoStream was greater than 97.1% and there was no difference in cell growth up to 7 days in culture compared to controls. The ApoStream device demonstrated high precision and linearity of recovery of viable cancer cells independent of their EpCAM expression level. Isolation and enrichment of viable cancer cells from ApoStream enables molecular characterization of CTCs from a wide range of cancer types. 相似文献
235.
In the context of increasing commercialization of certain sports its influence on the incidence of doping in sport is often discussed. Economic incentives should influence the decision of individuals in two ways. On the one hand the amount of prize money is mentioned and on the other hand relative influences which relate to the unequal distribution of funds depending on the ranking in the competition. Based on the consideration of prize money payments in international senior competitions in two independent survey years the level and distribution of prize money in competitions will be presented. The absolute amount of the prize money explains a significant proportion of the variance in the doping affinity in the observed sports disciplines (36?%). Unequal Payouts depanding on ranking, show no significant relationship to the doping affinity. The results thus provide indications on revenue opportunities through successful participation in competitions and some empirical evidence on economic arguments in connection with the doping debate. 相似文献
236.
Monika Slavíková František Krejčí Jan Žemlička Michal Pech Petr Kotlík Jan Jakůbek 《Journal of Cultural Heritage》2012,13(4):357-364
Stone consolidation is one of the major restoration treatments used for historical monuments preservation. A natural stone is a complicated heterogeneous porous system making the process of consolidation dependent on many variables. In practical restoration aims, for a given stone type, the selection of a suitable consolidant and consolidation conditions therefore remains a complex issue. The impregnation depth is a key factor for the assessment of the treatment efficiency. The combination of state-of-the-art hybrid pixel semiconductor detectors with newly available micro-focus X-ray sources makes possible to apply X-ray radiography, an ideal non-destructive tool, for penetration depth monitoring. In this study, high-resolution X-ray radiography is used for monitoring the penetration depth of organosilicon consolidants in the Opuka stone. The penetration depth has been evaluated in relation to the time of consolidation, stone porosity and consolidation mixtures properties. The exact influence of the X-ray contrast agent on the consolidation depth has been investigated as well. The information obtained provides supplementary knowledge on the suitability of investigated products for the treatment of this type of stone. In our study, the capabilities of X-ray radiography have been demonstrated on X-ray radiography simple projections, high-resolution computed tomography (CT) as well as on the dynamic processes monitoring. The results thus can serve also as an instrumental and methodological example applicable for consolidation monitoring of other stone types. 相似文献
237.
Robyn Preston Monica Gratani Kimberley Owens Poornima Roche Monika Zimanyi 《Assessment & Evaluation in Higher Education》2020,45(1):109-124
AbstractWhat and how students learn depend largely on how they think they will be assessed. This study aimed to explore medical students’ perception of the value of assessment and feedback on their learning, and how this relates to their examination performance. A mixed methods research design was adopted in which a questionnaire was developed and administered to the students to gain their perceptions of assessments. Perceptions were further explored in focus group discussions. Survey findings were correlated with students’ performance data and academic coordinators’ perceptions. Students’ perceptions of the level of difficulty of different assessments mirrored their performance in examinations, with an improvement observed in clinical assessments as students progressed through their degree. Students recognised that feedback is important to allow improvements and seek more timely, better quality and personalised feedback. Academic coordinators identified that some of the students’ suggestions are more realistic than others. Students had a positive attitude towards assessment, but emphasised the need for educators to highlight the relevance of assessment to clinical practice. 相似文献
238.
Jyoti Shekhawat Kavya Gauba Shruti Gupta Purvi Purohit Prasenjit Mitra Mahendra Garg Sanjeev Misra Praveen Sharma Mithu Banerjee 《Indian journal of clinical biochemistry : IJCB》2021,36(4):440
COVID-19 has emerged as a global pandemic. It is mainly manifested as pneumonia which may deteriorate into severe respiratory failure. The major hallmark of the disease is the systemic inflammatory immune response characterized by Cytokine Storm (CS). CS is marked by elevated levels of inflammatory cytokines, mainly interleukin-6 (IL-6), IL-8, IL-10, tumour necrosis factor-α (TNF-α) and interferon-γ (IFN-γ). Of these, IL-6 is found to be significantly associated with higher mortality. IL-6 is also a robust marker for predicting disease prognosis and deterioration of clinical profile. In this review, the pivotal role played by IL-6 in the immuno-pathology of COVID-19 has been illustrated. The role of IL-6 as a pleiotropic cytokine executing both pro and anti-inflammatory activities has been reviewed. ADAM 10, a metalloproteinase switches the anti-inflammatory pathway of IL-6 to pro inflammatory hence blocking the action of ADAM 10 could be a new therapeutic strategy to mitigate the proinflammatory action of IL-6. Furthermore, we explore the role of anti-IL6 agents, IL-6 receptor antibodies which were being used for autoimmune diseases but now are being repurposed for the therapy of COVID-19. 相似文献
239.
Prishni Gupta Pratishtha Agrawal Neha Rani Verma Seema Shah Suprava Patel Rachita Nanda Eli Mohapatra 《Indian journal of clinical biochemistry : IJCB》2021,36(3):345
The incidence of autoimmune disorders that includes the connective tissue diseases has seen a rise in India in recent times. Antinuclear antibodies, the telltale sign of systemic autoimmune response, thus can be used as a screening tool and also to support the diagnosis of systemic autoimmune disease. The present retrospective cross- sectional analysis aimed to study the antinuclear antibodies profile (patterns and specific antibody reactivity) amongst suspected cases of auto-immune disorders at a tertiary care teaching hospital. The study retrieved and reviewed reports of 644 patients sent for ANA testing by indirect immunofluorescence assay over a period of 1 year by different specialty departments. Positive samples were further processed for anti-ds-DNA antibody and antibodies to extractable nuclear antigen. Data collected was statistically analysed. ANA pattern positivity was observed in 31% of cases and a positive antibody reactivity was seen in 66% of them. Female predominance (82%) was noted in both pattern positivity and antibody reactivity. High levels of pattern positivity and antibody reactivity was found in the young adults (45.9%). Amongst the ANA patterns, the nuclear homogenous pattern was found the commonest. The common antibodies associated with this pattern were anti-dsDNA and U1 Sm/RNP antibodies. A stronger fluorescence intensity on initial screening showed a higher confirmation rate for specific antibodies on immunoassay. High occurrence of positive ANA patterns in autoimmune disorders suggests its utilization as a screening tool for them and would also play an adjuvant to the diagnosis. Early knowledge about future autoimmunity will earn better prognostic achievements through better treatment interventions. 相似文献
240.
Anita Somborac Ba
ura Marija Doroti Leonarda Groi Monika Dimbeg Slavica Dodig 《Biochemia medica : ?asopis Hrvatskoga dru?tva medicinskih biokemi?ara / HDMB》2021,31(2)
Early detection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and diagnosis of coronavirus disease 2019 (COVID-19) are priorities during the pandemic. Symptomatic and suspected asymptomatic individuals should be tested for COVID-19 to confirm infection and to be excluded from social interactions. As molecular testing capacity is overloaded during the pandemic, rapid antigen tests, such as lateral flow immunoassays (LFIAs), can be a useful tool as they allow greater test availability and obtain results in a very short time. This short review aims to present the analytical properties of LFIAs in the detection of SARS-CoV-2 in nasopharyngeal swabs. Lateral flow immunoassay is a method that combines thin-layer chromatography and indirect immunochemical sandwich method and allows the detection of a specific SARS-CoV-2 antigen in nasopharyngeal swabs. Swab specimens should be adequately collected and tested as soon as possible. Users should pay attention to quality control and possible interferences. Antigen tests for SARS-CoV-2 show high sensitivity and specificity in cases with high viral loads, and should be used up to five days after the onset of the first symptoms of COVID-19. False positive results may be obtained when screening large populations with a low prevalence of COVID-19 infection, while false negative results may happen due to improper specimen collection or insufficient amount of antigen in the specimen. So as to achieve reliable results, a diagnostic accuracy study of a specific rapid antigen test should be performed. 相似文献