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71.
Elevated plasma triglyceride and non-esterified fatty acid concentrations may cause insulin resistance and type 2 diabetes mellitus. Lipoprotein lipase (LPL) is a rate-determining enzyme in lipid metabolism. A variant in the LPL gene has been identified which alters the penultimate amino acid Serine at 447 to a stop codon (S447X), and results in a truncated LPL molecule lacking the C-terminal dipeptide Ser–Gly. The present study was designed to evaluate the frequency of S447X variant in the LPL gene and its effect on the lipid and lipoprotein levels in type 2 diabetic subjects. The genotype frequency distributions of type 2 diabetes patients and controls were in Hardy–Weinberg equilibrium. Comparison of the genotype and allelic frequencies of S447X in subjects with type 2 diabetics compared to controls demonstrated no significant difference. In subjects with type 2 diabetics having hypertriglyceridemia (TG ≥ 150 mg/dl) compared to diabetics with TG level <150 mg/dl, significant difference in genotype frequency was found among these groups, while allelic frequency of X was significantly differed. Logistic regression analysis showed the negative association of LPL S447X variant with TG and VLDL cholesterol, while no association with total cholesterol, HDL cholesterol and LDL cholesterol was found. The lipid levels except for HDL cholesterol were found to be significantly lower in carriers for S447X than wild type in diabetes group. The decreased level of TG and TG rich lipoprotein in subjects with SNP S447X in LPL, predicts anti-atherogenic activity of carriers for S447X variant in general population as well as type 2 diabetic patients.  相似文献   
72.
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   
73.
The objective of this study was to evaluate acrosin activity in spermatozoa of infertile Nigerian men and to compare with those of the fertile men. The acrosin activity was evaluated using the Acroscreen reagent kit. The acrosin activity of the fertile men was 40.7±5.2 mIU/106 sperm (range 30.1–51.3) and those of the infertile men was 22.4±8.33 mIU/106 sperm (range 5.7–39.1). The difference in the mean was statistically significant (P<0.001). There was a subpopulation of the infertile men who had their acrosin activity within normal range of the fertile men, 32.9±1.57 mIU/106 sperm. But the difference in the mean was statistically significant (P<0.001). Acrosin activity decreased with increased morphological changes in the spermatozoa. It is concluded that acrosin activity in the infertile Nigerian men is significantly lower than that in the fertile men. Acrosin activity may also be affected by morphological changes in the spermatozoa.  相似文献   
74.
This paper investigates the role of government R&D subsidy programs in stimulating knowledge spillovers. R&D subsidies are an effective public policy instrument when knowledge spillovers exist yet ex ante it is difficult to identify projects that have the greatest potential to increase innovation and economic growth. This paper derives a set of project and firm attributes that the literature finds generate knowledge spillovers and uses data on project proposals to estimate the degree to which a government R&D program conforms. We find that projects that were awarded R&D subsidies were more likely to have attributes such as participation in new research joint ventures and connections to universities and other firms. Following the post-award activities of firm, we find that receipt of a government R&D subsidy increased the funding from other sources when compared to firms that were not awarded funding.  相似文献   
75.
From January 1992-January 1998, 1404 patients attended the “Breast Clinic” of R.N.T. Medical College M.B. Hospital, Udaipur. Out of these, 11% and 81% patients had breast cancer (B.C.) and benign breast cancer (B.B.D.) respectively. The oxidative load in B.C. was 2.32 times higher than controls, but comparable to B.B.D. β-Carotene deficiency was uncommon in patients, whereas vitamin A deficiency was almost equally common in both B.C. and controls. Most of the patients had almost depleted levels of α-tocopherol and ascorbic acid but their TBAR levels were in normal range. The data in the present study when compared with B.B.D. and other local normal subjects point out: a) oxidative burden in B.C. is a consequence and not the cause of the disease, (b) oxidative stress could be one of the etiological factors in tumor expression, which need not to be malignant and c) α-tocopherol and ascorbic acid are not importantly responsible for higher oxidative burden in B.C.  相似文献   
76.
Statistical and Fourier analysis methods of time series representing fluctuations of stock market in general and Indian stock markets in particular are well known. This work is motivated by a recent paper by Guharay [Operations Research and Financial Engineering, Princeton University, Princeton, NJ, preprint, 2002] where he has studied trends in the S & P 500 for various time periods using wavelet tools. Our paper deals with a few Indian and Saudi stock prices and return fluctuation for a certain period of time. The main objective of the analysis is to understand the dynamics of the Indian and Saudi stock markets. We look for similarities, point of abrupt changes, normalized data, return, volatility, graph, pure and noise part, correlation lengths, and signal-to-noise ratio.  相似文献   
77.
Aprototype kit for the detection of occurrence of ovulation based on urinary pregnanediol glucuronide estimations by ELISA was developed in our laboratory. This kit was sent for evaluation at 4 centres in Bombay and Pune, India. The diagnosis of ovulation/anovulation based on the results of the kit is comparable with that based on reference parameters commonly used (ultrasonography of ovarian follicles and serum progesterone estimations). The accuracy of the test was 93.5%, specificity was 87.5% and sensitivity was 95.7%. This rapid indigenous test can be very useful in assessing ovulatory status of the woman by the clinicians in their offices.  相似文献   
78.
Artificial Life (ALife) has two goals. One attempts to describe fundamental qualities of living systems through agent based computer models. And the second studies whether or not we can artificially create living things in computational mediums that can be realized either, virtually in software, or through biotechnology. The study of ALife has recently branched into two further subdivisions, one is “dry” ALife, which is the study of living systems “in silico” through the use of computer simulations, and the other is “wet” ALife that uses biological material to realize what has only been simulated on computers, effectively wet ALife uses biological material as a kind of computer. This is challenging to the field of computer ethics as it points towards a future in which computer and bioethics might have shared concerns. The emerging studies into wet ALife are likely to provide strong empirical evidence for ALife’s most challenging hypothesis: that life is a certain set of computable functions that can be duplicated in any medium. I believe this will propel ALife into the midst of the mother of all cultural battles that has been gathering around the emergence of biotechnology. Philosophers need to pay close attention to this debate and can serve a vital role in clarifying and resolving the dispute. But even if ALife is merely a computer modeling technique that sheds light on living systems, it still has a number of significant ethical implications such as its use in the modeling of moral and ethical systems, as well as in the creation of artificial moral agents.  相似文献   
79.
Using our constitutive theory for polycrystalline plasticity, we have calculated characteristic yield conditions for several sample materials in which the dependence of the dislocation velocity on stress is given by an empirical power function. The shape of the yield surfaces for these materials varies resembling that of von Mises when the stress exponent is small and that of Tresca when the exponent is large. Additional examples illustrate the ability of the proposed theory to model such phenomena as the development of anisotropy during plastic deformation, material hardening and softening, the occurrence of upper and lower yield points, and a Bauschinger effect.  相似文献   
80.
The present study was undertaken in 100 subjects, 30 diabetics without complication (group I), 40 diabetics with retinopathy (group II) and 30 non diabetic as normal control group (group III). Blood sugar levels, magnesium, cholesterol and triglyceride were analyzed from plasma and serum. The results were correlated with degree of diabetic control from the levels of glycosylated hemoglobin. Serum magnesium levels in group II were found to be significantly lowered than in group I. There was also significant difference in magnesium levels of group I and group III. We found a significant correlation between the glycosylated hemoglobin and magnesium levels in our study. The results also indicate that the patients with diabetic retinopathy showed significant rise in serum cholesterol and triglyceride. Probably hypomagnesemia and increased serum cholesterol and triglyceride levels are responsible for microvascular changes in diabetes leading to retinopathy. The purpose of this study was thus to gather information about the degree of control of diabetes and magnesium status.  相似文献   
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