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81.
82.
N. Kapil A. R. Chowdhury H. Swarup 《Cellular and molecular life sciences : CMLS》1979,35(12):1606-1607
Summary The male gametogenic development of the immature rat shows inhibitory effect by the exogenous infusion of ACTH (0.25 IU and 0.50 IU; i.p.). Seminiferous tubular degeneration, Leydig cell atrophy and Sertoli cell regression are very conspicuous in the dosage of 0.50 IU ACTH (i.p.). Cytometrical and histological evidence confirms that ACTH could be inhibited by FSH during male gametogenic development which leads to cellular degeneration of testes in the immature rat.This work is supported by CSIR, Project No. JRF 37. We thank Md. K. Doubet for photomicrography. 相似文献
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85.
Saman Eskandarzadeh Kourosh Eshghi Mohammad Modarres Yazdi Mohsen Bahramgiri 《系统科学与系统工程学报(英文版)》2014,23(3):312-328
In this paper, we address a basic production planning problem with price dependent demand and stochastic yield of production. We use price and target quantity as decision variables to lower the risk of low yield. The value of risk control becomes more important especially for products with short life cycle. This is because, the profit implications of low yield might be unbearable in the short run. We apply Conditional Value at Risk (CVaR) to model the, risk. CVaR measure is a coherent risk measure and thereby having nice conceptual and mathematical underpinnings. It is also widely used in practice. We consider the problem under general demand function and general distribution function of yield and find sufficient conditions under which the problem has a unique local maximum. We also both analytically and numerically analyze the impact of parameter change on the optimal solution. Among our results, we analytically show that with increasing risk aversion, the optimal price increases. This relation is opposite to that of in Newsvendor problem where the uncertainty lies in demand side. 相似文献
86.
J. Bordner D. P. Chakraborty B. K. Chowdhury S. N. Ganguli K. C. Das B. Weinstein 《Cellular and molecular life sciences : CMLS》1972,28(12):1406-1407
Riassunto La struttura del murrayazoline, un'alcoloide carbazole, é stata confermata per via cristallografica con i raggi X. 相似文献
87.
A. R. Chowdhury M. B. Deshmukh C. D. Raghuveeran A. B. Nashikkar A. K. Chatterjee 《Cellular and molecular life sciences : CMLS》1978,34(10):1327-1327
Summary This communication describes histological changes in the thyroid gland of rats under the acute stress of O-chlorobenzylidene malononitrile (CS) (10 mg/kg and 20 mg/kg). It has been observed that CS, when injected, causes histological changes in the thyroid of varying degrees, depending on the dose used. 相似文献
88.
In recent years, a wide variety of studies have applied soft systems methodology (SSM) to address the complexities of the messy situations. This paper seeks to identify 1) application areas and 2) application levels of the use of SSM in dealing with problematical situations. To do so, 149 articles published between 2000 and 2015 were studied. The findings revealed the application of SSM in new application areas such as sustainable development, knowledge management and project management. The results of this study also indicated that researchers applied SSM at three levels: SSM as a process of inquiry, SSM as an action-oriented methodology, and the hybrid use of SSM. Based on the findings, SSM at the level of a single methodology for bringing out changes has been less welcomed by researchers, but the application levels of inquiry processes and hybrid approaches have been more utilized. This suggests that in the correspondence of SSM with the nature or situation of problems, a sort of incommensurability is witnessed. Factors arising from the nature of the problem, inadequate mastery of the researcher over SSM or the limitations of SSM can exert an influence on this incommensurability. 相似文献
89.
Ambra1 regulates autophagy and development of the nervous system 总被引:1,自引:0,他引:1
Fimia GM Stoykova A Romagnoli A Giunta L Di Bartolomeo S Nardacci R Corazzari M Fuoco C Ucar A Schwartz P Gruss P Piacentini M Chowdhury K Cecconi F 《Nature》2007,447(7148):1121-1125
Autophagy is a self-degradative process involved both in basal turnover of cellular components and in response to nutrient starvation or organelle damage in a wide range of eukaryotes. During autophagy, portions of the cytoplasm are sequestered by double-membraned vesicles called autophagosomes, and are degraded after fusion with lysosomes for subsequent recycling. In vertebrates, this process acts as a pro-survival or pro-death mechanism in different physiological and pathological conditions, such as neurodegeneration and cancer; however, the roles of autophagy during embryonic development are still largely uncharacterized. Beclin1 (Becn1; coiled-coil, myosin-like BCL2-interacting protein) is a principal regulator in autophagosome formation, and its deficiency results in early embryonic lethality. Here we show that Ambra1 (activating molecule in Beclin1-regulated autophagy), a large, previously unknown protein bearing a WD40 domain at its amino terminus, regulates autophagy and has a crucial role in embryogenesis. We found that Ambra1 is a positive regulator of the Becn1-dependent programme of autophagy, as revealed by its overexpression and by RNA interference experiments in vitro. Notably, Ambra1 functional deficiency in mouse embryos leads to severe neural tube defects associated with autophagy impairment, accumulation of ubiquitinated proteins, unbalanced cell proliferation and excessive apoptotic cell death. In addition to identifying a new and essential element regulating the autophagy programme, our results provide in vivo evidence supporting the existence of a complex interplay between autophagy, cell growth and cell death required for neural development in mammals. 相似文献
90.
A data-mining approach to biomarker identification from protein profiles using discrete stationary wavelet transform 下载免费PDF全文
Hussain Montazery-Kordy Mohammad Hossein Miran-Baygi Mohammad Hassan Moradi 《浙江大学学报(自然科学英文版)》2008,9(11):863-870
Objective: To develop a new bioinformatic tool based on a data-mining approach for extraction of the most informative proteins that could be used to find the potential biomarkers for the detection of cancer. Methods: Two independent datasets from serum samples of 253 ovarian cancer and 167 breast cancer patients were used. The samples were examined by surfaceenhanced laser desorption/ionization time-of-flight mass spectrometry (SELDI-TOF MS). The datasets were used to extract the informative proteins using a data-mining method in the discrete stationary wavelet transform domain. As a dimensionality reduction procedure, the hard thresholding method was applied to reduce the number of wavelet coefficients. Also, a distance measure was used to select the most discriminative coefficients. To find the potential biomarkers using the selected wavelet coefficients, we applied the inverse discrete stationary wavelet transform combined with a two-sided t-test. Results: From the ovarian cancer dataset, a set of five proteins were detected as potential biomarkers that could be used to identify the cancer patients from the healthy cases with accuracy, sensitivity, and specificity of 100%. Also, from the breast cancer dataset, a set of eight proteins were found as the potential biomarkers that could separate the healthy cases from the cancer patients with accuracy of 98.26%, sensitivity of 100%, and specificity of 95.6%. Conclusion: The results have shown that the new bioinformatic tool can be used in combination with the high-throughput proteomic data such as SELDI-TOF MS to find the potential biomarkers with high discriminative power. 相似文献