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排序方式: 共有5074条查询结果,搜索用时 31 毫秒
991.
Soma Gupta K. K. Singh V. J. Vyas V. N. Chaturvedi M. V. R. Reddy B. C. Harinath 《Indian journal of clinical biochemistry : IJCB》2000,15(1):52-55
Oxidative stress was studied by estimating plasma levels of malondialdehyde (MDA), beta carotene, vitamin E and erythrocytic
superoxide dismutase(E-SOD) activity in 50 cases of carcinoma of upper digestive tract which included carcinoma of oral cavity,
pharynx and oesophagus. While plasma MDA level was found to be increased (3.5±1.0 nmole/ml), a significant decrease in beta
carotene (81.2±14.5mg%), vitamin E (8.5±1.1 mg/L) level and E-SOD activity (657.0±80.6 U/G Hb) were observed in carcinoma
of upper digestive tract. Patients were treated with radiotherapy which itself was toxic enough and produced its deleterious
effects by generation of reactive oxygen species (ROS). As antioxdiants can detoxify ROS, beneficial effect if any, of antioxidant
administration during radiotherapy was studied in two groups of patients, group A (n=5, supplemented with antioxidants) and
group B (n=5, without antioxidant supplementation). Plasma MDA level was found to be elevated in both the groups but the increase
in group B was significant, compared to pretreatment level. Further, body weight was found to be significantly decreased in
group B patients, which was maintained in group A patients. Moreover, group A patients showed significant elevation in beta
carotene concentration, thus showing beneficial effect of administration of antioxidants during radiotherapy without disturbing
the desirable therapeutic effect of radiotherapy. 相似文献
992.
Philosophical foundations of quantum field theory 总被引:1,自引:0,他引:1
993.
Maria G. N. Musoke 《Health information and libraries journal》2000,17(4):194-202
A study was conducted in 1998/99 to investigate the accessibility and use of information by health workers in rural Uganda. Data were collected qualitatively using semi‐structured interviews. As a qualitative study, it focused in‐depth on a relatively small sample of health workers selected purposefully. Different categories of health workers were interviewed. Data were analysed using a grounded theory approach. In this paper, two main categories that emerged from the data will be discussed, namely: value of information and constraints. Information was valuable in clinical work, information dissemination, decision making, administration and detection. Constraints to effective information use included the quality and relevance of the information as well as the difficulties of sometimes putting theory into practice. Finally, the concepts that emerged from the analysis of the use of information pointed directly to the information needs of the health workers studied, which shows that information was valuable in meeting those needs. Some implications of the study and areas for further research are highlighted. 相似文献
994.
Efthimiadou A Asimakopoulos B Nikolettos N Giatromanolaki A Sivridis E Lialiaris TS Papachristou DN Kontoleon E 《Journal of sports sciences》2006,24(8):849-854
Although angiogenetic therapy using recombinant growth factors holds much hope for the treatment of ischaemic diseases, there are still many unanswered questions, including the method of administration, the correct dose of these factors, and the duration of the therapeutic approach. Exercise has also been suggested to induce neovascularizaiton in muscles. We evaluated the angiogenetic effects of the intramuscular administration of basic-fibroblast growth factor (b-FGF) and acidic-fibroblast growth factor (a-FGF) in rat heart, compared with rats who exercised daily. In conclusion, both the intramuscular administration of b-FGF and exercise increased significantly angiogenesis in the heart in contrast to the intramuscular administration of a-FGF, which was ineffective. 相似文献
995.
N.W Pirie 《Endeavour》1980,4(2):74-77
Victualling in space differs fundamentally from victualling on land or at sea because there is little chance of foraging or of finding local sources of oxygen and water, and all metabolic products have to be carefully collected even if they will ultimately be jettisoned. The need for a deliberate policy for coping with carbon dioxide, faeces, and urine leads naturally, to schemes for recycling. Entropy is increased when food is metabolised: energy will have to be expended for even partial restoration of the status quo. 相似文献
996.
M.O. Ahmad C.H. Reddy V. Ramachandran M.N.S. Swamy 《Journal of The Franklin Institute》1979,307(2):71-81
Necessary and sufficient conditions are obtained for the realization of an m-variable positive real function (PRF) as the impedence function of a resistively-terminated ladder network of m lossless two-ports connected in cascade. Each two-port is a single-variable lossless ladder with all of its transmission zeros either at the origin or at finity. Conditions are also obtained when each of the two-ports is a Fujisawa-type lowpass ladder. 相似文献
997.
998.
999.
The reproducibility of microwave integrated circuits can be improved by employing substrates which are anisotropic. A method is presented which facilitates the computation of the characteristics of distributed integrated microwave circuits of finite conductor thickness on anisotropic and inhomogeneous substrates. The method is variational and it relies on a quasi-static approach which assumes that the charge distribution on each side of the conductor can be represented by a spatially dependent set of exponential functions. 相似文献
1000.