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排序方式: 共有982条查询结果,搜索用时 15 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
2.
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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A K Ganguli R Hemalatha B Narayanan 《Indian journal of physiology and pharmacology》1986,30(4):313-318
Blood lactate assays are now widely used as measures of oxygen debt, especially in the areas of assessment of anaerobic power; assessment of fatigue; VO2(max) end-point determination, and rationalisation of work-rest cycles. A need exists for a method which will meet the following criteria: simplicity--single, small samples; rapidity, and feasibility with easily available instrument and chemicals. In order to develop such a method, the standard Barker and Summerson method was modified so as to use 0.02 ml of blood sample, and the following tests were carried out on 25 subjects at rest, and various levels of work: paired comparisons on analysis by macro and micro methods on the same sample of blood; paired comparisons on venous and capillary (fingertip) samples. In both cases, the paired values showed high correlation (0.99) and highly significant differences of means (P = 0.01 and 0.001, respectively). The regression equations obtained were also highly significant (P = 0.001). The combined equation was Y = 0.9655 X -0.4366; samples taken 2,4,5,6 and 10 mins after work showed that peak occurred in the 4th min sampling (2 vs 4 and 4 vs 6 min means significantly different at P = 0.05, and analysis of variance significant at (P = 0.001). It may be concluded that drawing, fingertip sample 4 mins after the end of work, analysing by the micro method, and using the regression equation will give the true peak blood lactate level, and satisfy the systems criteria defined. 相似文献
8.
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
9.
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
10.
Genetic variability of begomoviruses associated with cotton leaf curl disease originating from India 总被引:4,自引:1,他引:4
Kirthi N Priyadarshini CG Sharma P Maiya SP Hemalatha V Sivaraman P Dhawan P Rishi N Savithri HS 《Archives of virology》2004,149(10):2047-2057
Summary. Cotton leaf curl disease (CLCuD) causing viruses belong to the Begomovirus genus of the family Geminiviridae. Most begomoviruses are bipartite with two molecules of circular single stranded DNA (A and B) encapsidated in icosahedral geminate particles. However, the begomoviruses associated with CLCuD have DNA- instead of DNA-B. In this communication we report the complete genomic sequence of DNA-A component of two CLCuD-causing begomoviruses, cotton leaf curl Kokhran virus-Dabawali (CLCuKV-Dab), tomato leaf curl Bangalore virus-Cotton [Fatehabad] (ToLCBV-Cotton [Fat]) and partial sequences of two other isolates cotton leaf curl Rajasthan virus-Bangalore (CLCuRV-Ban) and cotton leaf curl Kokhran virus-Ganganagar (CLCuKV-Gang). A phylogenetic analysis of these isolates along with other related begomoviruses showed that ToLCBV-Cotton [Fat] isolate was closest to the tomato leaf curl Bangalore virus-5 (ToLCBV-Ban5) where as CLCuKV-Dab isolate was close to the cotton leaf curl Kokhran virus-Faisalabad1 (CLCuKV-Fai1), cotton leaf curl Kokhran virus-72b (CLCuKV-72b) and cotton leaf curl Kokhran virus-806b (CLCuKV-806b) isolates from Pakistan. The phylogenetic analysis further showed that the ToLCBV-Cotton [Fat] and CLCuKV-Dab isolates along with CLCuKV-Fai1, CLCuKV-72b and CLCuKV-806b are closer to the ToLCBV, tomato leaf curl Gujarat virus (ToLCGV), tomato leaf curl Gujarat virus-Varanasi (ToLCGV-Var) and tomato leaf curl Sri Lanka virus (ToLCSLV) isolates, where as cotton leaf curl Alabad virus-804a (CLCuAV-804a), cotton leaf curl Multhan virus (CLCuMV) cluster with the isolates from cotton leaf curl Rajasthan virus (CLCuRV) and okra yellow vein mosaic virus (OYVMV). These results demonstrate the extensive variability observed in this group of viruses. The AC4 ORF is the least conserved among these viruses. In order to further asses the variability in the CLCuD-causing begomoviruses, the region showing minimum similarity in the DNA-A sequence was first determined by a comparison of segments of different lengths of the aligned sequences. The results indicated that region 2411–424 (771nt) was the least conserved. A phylogenetic tree constructed using the sequences of all the CLCuD causing begomoviruses, corresponding to the least conserved region showed that they form two distinct clusters. 相似文献