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排序方式: 共有1026条查询结果,搜索用时 406 毫秒
1.
Pankaj Dabir Snehal Dabir B V Siva Prasad M V R Reddy 《Infection, genetics and evolution》2006,6(4):287-291
Molecular characterization of Wuchereria bancrofti is essential to develop suitable anti-filarial drugs and vaccines. We describe here isolation, sequence analysis and cloning of a partial cDNA of an enzyme superoxide dismutase from this parasite. The immunoscreening of a lambda zap W. bancrofti microfilarial (Mf) cDNA library with microfilaremic sera had resulted in the isolation of several seroreactive clones including, WbSOD. This clone contained a 309 bp insert and showed significant nucleotide and deduced amino acid sequence homologies to the superoxide dismutases of other nematode parasites. The antioxidant property of this enzyme may have important contribution in the defense mechanism of the parasite against host immune response. 相似文献
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Zongli Lin Meir Pachter Siva Banda Yacov Shamash 《Optimal control applications & methods.》2002,23(1):21-43
A design technique (Control of Uncertain Systems with Bounded Inputs, Tarbouriech S, Garcia G, (Eds), Lecture Notes in Control and Information Sciences, vol. 227 , Springer: Berlin, 1997; 173–186) recently proposed for stabilization of a linear system with rate‐limited actuators is utilized to design feedback laws that cause the system output to track a desired command signal. This design technique combines two design techniques recently developed for linear systems with position limited actuators, piecewise‐linear LQ control (Automatica, 1994; 30 : 403–416) and low‐and‐high gain feedback (IEEE Trans. Automat. Control, 1996; 41 : 368–378), and hence takes advantage of both design techniques, while avoiding their disadvantages. In the case that only the output is available for feedback, the performance of the state feedback law is preserved by the use of a fast observer. An open‐loop exponentially unstable fighter aircraft is used to demonstrate the effectiveness of the proposed control design method. Copyright © 2002 John Wiley & Sons, Ltd. 相似文献
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Andrew G. Sparks Hsi-Han Yeh Siva S. Banda 《Optimal control applications & methods.》1990,11(4):307-325
This paper introduces a design methodology for a dynamic compensator that simultaneously minimizes the upper bound of a quadratic performance index and the H∞-norm of a disturbance transfer function matrix of a multiple-input/multiple-output system whose model contains parameter uncertainty in the state and input matrices. The real parameter uncertainty is modelled as additional measurement outputs and as additional weights on the existing noise inputs and measurement outputs of the system. The compensator equations are derived by taking the dual of a system with parameter variation in the state and output matrices, for which the compensator equations have previously been derived, and then taking the dual of the compensator equations. An algorithm for applying this theory is given and an example is shown. 相似文献
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Transient Osteoporosis of the Hip in Pregnancy 总被引:1,自引:0,他引:1
Sashi Siva Vijay Roach 《The Australian & New Zealand journal of obstetrics & gynaecology》1997,37(3):261-266
Summary: Transient osteoporosis of the hip (TOH) is an uncommon condition. This painful regional osteoporosis affects previously healthy women in the third trimester of pregnancy. It is characterized by pain in the affected hip and pronounced osteopenia of the femoral head and neck. It has a relatively short clinical course (average 6 months) and a predictably benign prognosis. Complete clinical and radiological recovery is the rule. The diagnosis is one of exclusion. The cause of the osteopenia is not known, although various aetiological factors have been implicated. A case of TOH occurring in the third trimester of pregnancy with complete recovery within 6 months postpartum is presented. 相似文献
8.
Siva Narayanan John Van Vleet Billy Strunk Robert N Ross Mikel Gray 《Journal of wound, ostomy, and continence nursing》2005,32(3):163-170
This study compared clinical outcomes and nursing labor costs associated with (a) balsam Peru, hydrogenated castor oil, and trypsin (BCT) ointment; (b) BCT + Other; and (c) Other treatments in 2014 wound episodes occurring in 861 patients (mean 2.34 wounds/patient). Treatment with BCT ointment or BCT + Other was associated with a higher healing rate (P < .05). No Stage 1 or 2 ulcer treated with BCT ointment progressed, compared with 13.8% treated with BCT + Other and 13.4% treated with Other. The reported mean duration of treatment and time to heal were shorter for ulcers treated with BCT ointment, but differences did not reach significance, possibly because of the variability in reported treatment times. Mean daily nursing labor costs were lower for treatment with BCT than Other ($50.8 vs $61.7, P < .05). These data suggest that treatment of Stage 1 or 2 ulcers with BCT may be associated with shorter treatment time and time to heal and a potential reduction in treatment-related nursing labor costs. 相似文献
9.
Shkolnikov VM McKee M Vallin J Aksel E Leon D Chenet L Meslé F 《International journal of epidemiology》1999,28(1):19-29
BACKGROUND: The dramatic increase in mortality in Russia and Ukraine in the late 1980s and 1990s has been due to increases in certain causes of death, particularly cardiovascular disease and accidents and violence. In contrast, there has been a slight fall in mortality from cancer. METHODS: This paper presents an analysis of trends and patterns in cancer mortality and examines four possible explanations for its recent fall: changes in data collection; cohort effects; competing mortality from other causes of death; and improvements in health care. RESULTS: All contribute to some extent to the observed changes, with each affecting predominantly different age groups. There is evidence of a significant underrecording of cancer deaths among the elderly especially in rural areas and of significant changes in coding practices in the early 1990s. Competing mortality from cardiovascular diseases and accidents can explain some reduction in male deaths from cancer in middle age. Birth cohort effects can explain some reduction among males after early middle age and among females at all ages. The impact of changes in health care are more difficult to identify with certainty but there is evidence of reduced deaths from childhood leukaemia. IMPLICATIONS: Recent changes in mortality in Russia are complex and their understanding will require a multidisciplinary approach embracing demography, epidemiology and health services research. 相似文献
10.
Kumar Rajagopalan David Peereboom G. Thomas Budd Thomas Olencki Siva Murthy Paul Elson Denise McLain Ronald Bukowski 《Investigational new drugs》1999,16(3):255-258
Circadian administration of chemotherapy has been reported to decrease toxicity and possibly enhance efficacy. Between March 1991 and December 1993, 18 evaluable patients with progressive, hormone-refractory metastatic prostate cancer were treated in this phase II trial of circadian infusion floxuridine (FUDR). The drug was delivered through a central venous catheter using a CADD-Plus computerized pump such that approximately 70% of the drug was administered between 3 and 9 p.m. and the rest (30%) was administered between 9 p.m. and 3 p.m. The dose of FUDR was 0.15 mg/kg/day × 14 days every 4 weeks. A total of 79 complete cycles was administered.Two of 18 evaluable patients (11.1%) had decreases in PSA lasting five and eight months. No objective responses or improvement in bone scans was noted. The major toxicity observed was diarrhea. Although circadian infusion FUDR is feasible and tolerable, it has limited activity in hormone refractory prostate cancer. 相似文献