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971.
R. Shukia S. B. Sharma D. Puri K. M. Prabhu P. S. Murthy 《Indian journal of clinical biochemistry : IJCB》2000,15(1):169-177
Many plants have been used for the treatment of diabetes mellitus in Indian system of medicine and in other ancient systems of the world. Out of these only a few have been evaluated as per modern system of medicine. From many such plants only extracts have been prepared and their usefulness evaluated in experimental diabetes in animals. In some plants likeAllium cepa, Allium sativum, Ficus bengalensis, Gymnema sylvestre, Pterocarpus marsupium etc. active hypoglycemic principles have been isolated and their mechanism of action studied. Most of them seem to act directly on pancreas (pancreatic effect) and stimulate insulin level in blood. Some have extra pancreatic effect also by acting directly on tissues like liver, muscle etc. and alter favourably the activities of the regulatory enzymes of glycolysis, gluconeogenesis and other pathways. Since the plant products have less side effects, they have the potential as good hypoglycemic drugs. They may also provide clues for the development of new and better oral drugs for diabetes. 相似文献
972.
Pontryagin's maximum principles are applied to obtain the solution of minimum mass convective fins with variable heat transfer coefficients. It is shown that the volume and the width of the fin are uniquely related to the specified heat transfer rate and the properties of the material. For a power law spatial variation of the heat transfer coefficient, the results are set forth in a dimensionless form and they are given in tables or graphs, in order to aid design procedures. Several properties relating to the optimum volume, base thickness and the width of the fins with the properties of the material are also discussed. The method can also be used to solve problems of minimum mass fins having restricted width, often encountered in practice. 相似文献
973.
Bhawana Nigam S. P. Joshi Seema Nagar Rajesh Chavan D. Pendharkar 《Indian journal of clinical biochemistry : IJCB》1996,11(2):124-128
The analysis of biochemical parameters in 162 patients with various neoplastic disorders along with 50 normal subjects showed significant rise in serum alkaline phosphatase and lactate dehydrogenase as compared to normal subjects. 21 patients with other monoclonal gammopathies which include infection and immunological diseases were also studied. Parameters such as serum calcium, uric acid, total protein, albumin and globulin were also analyzed in 42 (26%) cases of multiple myeloma, 27 (17%) cases of gastro-intestinal malignancies, 22 (14%) cases of urogenital malignancies, 11 (6%) cases of carcinoma breast, 4 (2%) cases of bone tumors, 21 (12%) cases of other monoclonal gammopathies, including 7 (4%) cases of infection and 14 (8%) cases of immunological diseases. The results indicate use of enzymes alkaline phosphatase and lactate dehydrogenase in neoplastic disorders. 相似文献
974.
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
975.
Steven J. Sackett James M. Kelley Peter P. Gillis 《Journal of The Franklin Institute》1977,304(1):47-63
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
976.
Ajay Kumar T. A. Venkita Subramanian Usha P. Sharma 《Indian journal of clinical biochemistry : IJCB》1992,7(2):165-168
Protein fraction termed P2 was obtained from sonicates of Mycobacterium smegmatis, subjected to ammonium sulphate precipitation. P2 fraction was further fractionated into 4 fractions (PeakI-IV) by DEAE cellulose ion-exchange chromatography. ELISA was performed
on the sera of 104 tuberculous cases and 62 controls, using P2 fractions Peak I as test antigens. Though the mean ELISA values in tuberculous cases were higher than the controls, no statistically
significant difference was found between the two. Antigens P2, Peak I and IV were tested on Western blots with pooled sera from tuberculous cases as well as controls. P2 fraction, Peak-I and IV were separated on PAGE-SDS, electroblotted onto nitrocellulose Sheets and the blots were subjected
to ELISA. Peak IV appeared as a single band (M.W. 55,000). P2 fraction exhibited some discriminatory bands on development of blots. 相似文献
977.
In this paper, an algorithm is developed to apply Hann, Hamming, Blackman and related windows directly in the transform domain for the discrete cosine transform and discrete sine transform. These algorithms are useful in applications where windowing is required in order to minimize edge effects caused by implicit symmetries in the transform domain that are not replicated in the real-world data. Examples of such applications include data communication, adaptive system identification and filtering, real-time analysis of financial market data, etc. Software implementations in C language are also given. 相似文献
978.
Praveen Sharma P. K. Sharma D.Sc. J. Pramod L. K. Kothari Rashmi Ranka Sushma Sharma 《Indian journal of clinical biochemistry : IJCB》1989,4(1):62-64
Sixteen weeks of chronic vitamin C deficiency, induced in guinea pigs by restricted vitamin C intake, resulted in a marked
increase in the serum total LDL- and VLDL- cholesterol, triglycerides and total lipids. HDL-cholesterol decreased resulting
in a highly significant increase in LDL/HDL ratio. The results reconfirm that vitamin C deficiency causes changes in blood
lipid profile which could promote atherogenesis. 相似文献
979.
980.
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