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1.
Serum Beta human chorionic gonadotropin (BhCG) was measured in 25 healthy controls and 75 cases with gestational trophoblastic neoplasms and testicular tumor using RIA kit from BARC, Bombay and ELISA kit from Abbott Diagnostics, USA. Regression Analysis of the values obtained for controls and cases by both the methods were statistically significant P 0.001.  相似文献   
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Circulating levels of gonadotropins (FSH,LH), prolactin (PRL), estradiol and progesterone were measured by radioimmunoassay in the sera of 60 patients with histopathologically proven breast cancer. 30 patients belonged to the post and 30 to the premenopausal group. 30 healthy women, 15 each in the pre and post menopausal groups served as controls for the study. Prolactin was elevated in 33% and 26% of pre and post menopausal breast cancer patients respectively. Lower levels of estradiol and progesterone were observed during the luteal phase of the menstrual cycle in premenopausal breast cancer patients. Among postmenopausal patients with breast cancer, LH was elevated in 32%, FSH in 15% and estradiol in 30% of the patients studied.  相似文献   
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This exploratory study examined the influence of national and organizational culture on the use of various performance improvement interventions. Data on intervention use were collected from practitioners in the United States and South Asia. Results revealed that orientation programs, organizational communication, instructor‐led training, and performance appraisals were among the most used interventions in both the United States and South Asia. Findings also indicated that factors such as organization size, location of headquarters, learning and development budget, and reporting structure are related to the use of interventions. Practitioners in South Asia predominantly had expertise in disciplines such as human resources, while those in the United States had experience in instructional design and human performance technology. These differences may influence the development and implementation of instructional and noninstructional interventions.  相似文献   
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Sriram Ramaswamy 《Resonance》2005,10(12):106-124
This article reviews the history of the phenomenon of Brownian motion, how it confirmed the molecular view of matter, and how it led to the invention of nonequilibrium statistical mechanics.  相似文献   
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This paper reports the results of a pilot-study in a senior paper science and engineering class, of an innovative instructional method designed to foster student problem-solving and in-depth learning of material, namely, student peer teaching. We review related literature focusing on active learning methods in science and engineering education, describe the method of student peer teaching used in this pilot-study, present the evaluation method and results, and discuss implications for further development of this method of instruction. Results suggest that students were able to effectively teach significant curricular content. In addition, the method of student peer teaching served important purposes in helping students develop in-depth understanding and expertise in the issues related to their teaching session, as well as teaching and presentation skills which will be useful in their professional practice. However, students expressed concern that, while achieving in-depth learning of the content of their teaching session, they tended to focus on the content area of their teaching session at the expense of other content areas and may not have learned as well from other students as from the Professor. We recommend a modified structure for student peer teaching which incorporates cooperative learning methods; increased Professor involvement in class sessions, in the role of the mentor; and modifications in performance evaluation methods to ensure ongoing student monitoring of progress and self-assessment. The method of student peer teaching, in science and engineering education, combined with cooperative learning methods, is viewed as a major extension of cooperative learning methods, used in the service of preparation for professional careers.  相似文献   
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Traditionally the kinetics of a chemical reaction has been studied as a set of coupled ordinary differential equations. The law of mass action, a tried and tested principle for reactions involving macroscopic quantities of reactants, gives rise to deterministic equations in which the variables are species concentrations. In recent years, though, as smaller and smaller systems – such as an individual biological cell, say – can be studied quantitatively, the importance of molecular discreteness in chemical reactions has increasingly been realized. This is particularly true when the system is far from the ‘thermodynamic limit’ when the numbers of all reacting molecular species involved are several orders of magnitude smaller than Avogadro’s number. In such situations, each reaction has to be treated as a probabilistic ‘event’ that occurs by chance when the appropriate reactants collide. Explicitly accounting for such processes has led to the development of sophisticated statistical methods for simulation of chemical reactions, particularly those occurring at the cellular and sub-cellular level. In this article, we describe this approach, the so-called stochastic simulation algorithm, and discuss applications to study the dynamics of model regulatory networks.  相似文献   
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Folate and cobalamin (Vitamin B12) are two essential micronutrients involved in one-carbon metabolism, which affects heart disease, neural tube defects and cancer. Methylenetetrahydrofolate reductase, the key enzyme involved in one carbon metabolism produces methyl tetrahydrofolate from methylene tetrahydrofolate, which in turn donates methyl group to homocysteine to generate methionine. There exist two common low function polymorphic variants of the methylenetetrahydrofolate reductase gene involving nucleotides 677 C→T and 1298 A→C, which are associated with hyperhomocysteinemia. These polymorphisms are also linked with increased risk for certain cancers such as breast cancer and at the same time providing a protective effect on colorectal cancer. In this case control study, we have evaluated levels of folic acid, vitamin B12 and homocysteine in patients with colorectal cancer. Folate and homocysteine levels did not differ significantly between the two groups; however an increasing trend was noticed with increase in homocysteine levels. Vitamin B12 levels were increased in cases compared to control group.  相似文献   
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HER-2 is overexpressed in approximately 20–30% of invasive Breast Cancer. ECD of the HER-2 protein is frequently cleaved and released into the circulation, where it can be detected by ELISA in up to 45% of patients with metastatic breast cancer. The objective of our study was to compare the current methods for the detection of HER-2 protein. Tissue HER-2 levels were studied in 100 breast cancer patients by IHC and compared with serum HER-2 levels by ELISA. IHC frequency was 29%. Serum HER-2 ECD was positive in 42% of patients. A statistically significant correlation was observed. HER-2 detected by IHC correlates significantly with serum HER-2 levels detected by ELISA. Thus, ELISA is a reliable and economical tool to assess the HER-2 status in tumors, when breast tissue sample is not available.  相似文献   
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