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排序方式: 共有3898条查询结果,搜索用时 15 毫秒
1.
Rajesh Bhat Alison Severn Sam Chakraverty 《Nephrology, dialysis, transplantation》2006,21(9):2642-2643
Placement of tunnelled dialysis lines is effective using ultrasoundand fluoroscopic guidance [1] and has a higher success ratethan blind insertion [2]. After the ultrasound guided access into a neck vein, wires andcatheters are guided in to a suitable position in the 相似文献
2.
A. O. Azghani J. W. Baker S. Shetty E. J. Miller G. J. Bhat 《Inflammation research》2002,51(10):506-510
OBJECTIVE AND DESIGN: Bacterial products as well as the host airway inflammatory responses contribute to the pathogenesis of Pseudomonas infections. We sought to determine if Pseudomonas elastase (PE) induces mitogen-activated protein (MAP) kinase activity in association with interleukin-8 (IL-8) production by alveolar epithelial cells. METHODS: We utilized Western blot analysis to detect phosphorylation of signaling intermediates and ELISA was used to measure IL-8 production. RESULTS: We found that PE induces phosphorylation of the extracellular signal-regulated (ERK1/2) proteins of the MAPK pathway in A549 epithelial cells. Similar results were obtained using primary cultures of rabbit alveolar type II epithelial cells. PE also enhanced IL-8 production, which was abolished in the presence of the ERK activation inhibitor U0126. CONCLUSIONS: We conclude that PE activates the ERK1/2 arm of the MAPK pathway and that activation of this pathway results in enhanced IL-8 production. The results demonstrate that PE may augment pulmonary inflammation via cellular signaling that regulates expression of IL-8. 相似文献
3.
Gayatri Vasudevan R. Chandra B. Vishnu Bhat B. D. Bhatia 《Indian Journal of Thoracic and Cardiovascular Surgery》1993,9(1):42-44
We present two cases of neonatal pleural effusion, a relatively rare condition, most commonly due to chylothorax. One had
bilateral hypoplastic lungs and the other suffered birth asphyxia. Both died before any treatment could be initiated. 相似文献
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Asymptomatic infection with Loa loa, an eye worm, is reported in a 32-year old Zambian woman. The patient revealed up to 28% eosinophilia but microfileraemia was not noticed. One gravid female parasite 56 X 0.56 mm, extracted from lower lid of left eye of the patient, is described. Treatment with diethylcarbamazine (DEC) extended over three weeks was successful against another parasite in tissues. 相似文献
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Design and real‐time validation of a robust fixed‐order H2 optimal controller for micro aerial vehicle, named Sarika‐2, is presented. Strengthened discrete optimal projection equations, which approximate the first‐order necessary optimality condition, are used for the controller design. Effect of low‐frequency gust disturbance and high‐frequency sensor noise is alleviated through the output sensitivity and control sensitivity minimization. The novelty of this paper is that a single robust H2 controller, which is designed at the central operating point, ensures simultaneous stabilization of the radio‐controlled aircraft over the entire cruise speed range of 16–26 m/s. The controller is implemented on a digital‐signal‐processor‐based flight computer, and subsequently, it is validated through the real‐time hardware‐in‐loop‐simulation. The responses obtained from the hardware‐in‐loop‐simulation compares well with those obtained from the off‐line simulation. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
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A. G. Sreenatha M. Seetharama Bhat S. K. Shrivastava 《Optimal control applications & methods.》1990,11(1):51-66
The design of a low-order dynamic output feedback controller for a flexible spacecraft is carried out using modified linear quadratic Gaussian (LQG) theory. The necessary conditions for optimization are given. The linear equations governing a flexible spacecraft with a central rigid body and two sun-tracking solar panels are presented. The parameters of the Solar Electric Propulsion Spacecraft (SEPS) are selected for analysis and simulation. The optimal gains for the dynamic controller are estimated using an iterative algorithm. The sequential procedure which assures convergence is selected. The initial gains which stabilize the system are chosen on the basis of the principle of a PD controller. A third-order controller for pitch, roll and yaw axes of the 18th-order system, which includes sensor and actuator dynamics, is designed. Numerical simulations carried out to ascertain the performance of the controller show the performance to be satisfactory. 相似文献