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61.
As a stress agent, inducing apoptosis and blocking it, Cd can have both helpful and harmful effects. The atmosphere is a thin envelope which makes the worid a global village. Cd is the most toxic metal in air. As both the first and second messenger of the stress response, it is synergistically toxic with all other stressors, including many other carcinogens. Elimination of Pb and its replacement with added benzene in gasoline appears to have increased the toxicity of atmospheric Cd. With scientific understanding of the molecular basis of Cd's role in carcinogenesis and anti-carcinogenesis, primary cancer prevention can be practiced by reducing Cd and chemical air pollution and educating the public on smoke cessation, healthy eating habits and stress reduction. Using the existing information on Cd and its effects, determinations could be made on established cancers so that individualized treatment protocols can be developed to improve patient care.  相似文献   
62.
The cysteine proteinases like cathepsins B, L and H are main hydrolytic enzymes present in lysosomes and play an important role in intracellular protein degradation. Tuberculosis and leprosy, both are tissue- destructive diseases. Main drugs used in chemotherapy of these diseases may inhibit the main lysosomal cysteine proteinases i.e. cathepsins B, L and H released during tissue destruction and thus prevent the further destruction of tissue by these enzymes. So the aim of this study is to see the effect of antituberculous and antileprotic drugs on these proteolytic enzymes. The effect of commonly used antituberculous and antileprotic drugs was screened on the activities of purified brain lysosomal cysteine proteinases namely cathepsins B [EC 3.4.22.1], L [EC 3.4.22.15] and H [EC 3.4.22.16]. Among the antileprotic drugs, only clofazimine inhibited the enzymic activities whereas dapsone had no effect whatsoever. In antituberculous drugs, rifampicin was the most inhibitory while isoniazid had little inhibitory potency. Streptomycin and pyrazinamide did not effect the activities at all. As regards the mechanism of inhibition, clofazimine and isoniazid inhibited the enzymes in a non-competitive manner with K values of 0.25 mM and 5.0 mM for cathepsin B, 0.071 mM and 0.833 mM for cathepsin L and 1.513 mM and 0.885 mM for cathepsin H, While rifampicin could effect in a competitive manner with Ki values of 0.03 mM, 0.125 mM and 0.027 mM for cathepsin B, L and H respectively.  相似文献   
63.
BALP activity in the sera of metastatic patients of breast and prostate malignancy has increased significantly. Our studies with patients in India conform the earlier reports that BALP may have a useful complementary role in the early diagnosis of bone metastases.  相似文献   
64.
We investigated the effect of cholesterol and the metalloporphyrins cobalt mesoporphyrin (CoMP) and chromium protoporphyrin (CrPP) on phospholipase A2 (PLA2) activity and the consequent hepatic mitochondrial stability as well as on lipid concentrations. Our studies revealed that on administration of cholesterol, CrPP, CoMP as well as simultaneous adminstration of cholesterol and CrPP, there was an inhibition of PLA2 activity. These moieties may therefore, be agents for preventing destabilisation of the mitochondrial membrane and the consequent pathological conditions which may arise due to membrane lysis. Our results revealed that cholesterol administration increased phospholipid concentration, albeit by modest amounts. Although the independent administration of metalloporphyrins led only to minor elevations in phospholipid concentration, the simultaneous administration of cholesterol and CrPP generated a steep elevation in the concentration of total phospholipid. Since cholesterol inhibits PLA2 activity it has the potential of being therapeutic agent for preventing the pathological conditions which may arise due to membrane lysis.  相似文献   
65.
Kelvin and the geologists argued about the age of the earth for nearly four decades. But the fate of Kelvin’s view was sealed when the results of research on radioactivity became available at the beginning of the twentieth century.  相似文献   
66.
The antidyslipidemic activity of Hibiscus rosa sinensis (Malvaceae) root extract has been studied in alloxan induced diabetic rats. In this model, oral administration of root extract (500 mg/kg bw. p.o.) for 15 days resulted in significant decreased in the levels of blood glucose, plasma lipids and reactivated post heparin lipoprotein lipase activity in alloxan induced diabetic rats. Furthermore, the root extract (50–500 μg) when tested for its antioxidant activity, inhibited the generation of super oxide anions and hydroxyl radicals, in both enzymic and non enzymic systems in vitro. The results of the present study demonstrated antidyslipidemic and antioxidant activities in root extract of H. rosa sinensis which could be used in prevention of diabetic-dyslipidemia and related complications.  相似文献   
67.
Web 2.0 technologies have introduced increasingly participatory practices to creating content, and museums are becoming interested in the potentials of “Museum 2.0” for reaching and engaging with new audiences. As technological advances are opening up the ways in which museums share information about the objects in their collections, the means by which museums create, handle, process, and transmit knowledge has become more transparent. For this to be done effectively, however, some underlying contradictions must be resolved between museum practices, which privilege the account of the “expert,” and distributed social technology practices, whose strengths lie in allowing for many, sometimes contradictory, perspectives. This article presents a theoretical position and framework for the adaptation of Web 2.0 technologies within the traditional work of the museum, in ways that support the generation and representation of knowledge in, by, and for diverse communities. We then expand on this theoretical perspective by discussing several case studies of exploratory work in this area, and close the article by presenting a few tactical, bottom-up initiatives that museums and distributed communities can take to facilitate the diffusion of this new conceptual framework. Though the subject of this article is online museums, the issues are relevant to all online collections, in particular portals, online public access catalogs (OPAC), and content management systems.  相似文献   
68.
Clinical reference intervals among Indian population are poorly defined. Therefore, there is an urgent need to establish local clinical laboratory reference intervals for healthy Indian population. The present study aimed to identify the 95 % reference interval for hematological and biochemical parameters in apparently healthy Indian population. We undertook a multicentric cross-sectional study conducted at Apollo Hospitals Educational and Research Foundation across India. Of which 10,665 reference individuals identified as healthy by physicians. The 95 % of the reference distribution was estimated using 2.5th and 97.5th percentile reference limits. The 95 % reference intervals for hemoglobin (Males: 12.3–17 g/dL; Females: 9.9–14.3 g/dL), platelet count (Males: 1.3–3.8; Females: 1.3–4.2 Lakhs/µL), erythrocyte sedimentation rate (Males: 2–22; Females: 4–55 mm/h), serum uric acid in males: 3.5–8.2 mg/dL, gamma glutamyl transferase (Males: 13–61 U/L), fasting blood glucose (Males: 78–110 mg/dL), total cholesterol (Males: 115–254 mg/dL), low density lipoprotein (Males: 60–176 mg/dL) and triglycerides (Males: 55–267 mg/dL, Females: 52–207 mg/dL) were different from currently used reference values. Additionally need for gender based partitioning were observed for triglycerides and gamma glutamyl transferase. The observed findings are of clinical significance and it needs to be validated with additional community based studies.  相似文献   
69.
70.
The present study was carried out to evaluate the hypoglycemic, lipid lowering and antioxidant activities in root extract of Anthocephalus indicus (A indicus) in alloxan inducd diabetic rats. Oral administration of ethanol extract of root (500mg/ kg body weight) for 21 days resulted in significant decrease in the levels of blood glucose, triglycerides, total cholesterol, phospholipid and free fatty acids. Furthermore, the root extract (100–400μg) inhibited the generation of superoxide anions and hydroxyl radicals, in both enzymic and non-enzymic systems, in vitro. The result of the present study demonstrated hypoglycemic, lipid lowering and antioxidant activities in root extract of A indicus, which could help in prevention of diabetic dyslipidemia and related diseases.  相似文献   
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