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41.
A 32–year–old man had an unusual gunshot wound to the leg, causing a peroneal nerve palsy. Sonography provided useful complementary findings to the electrodiagnostic localization of the injury. 相似文献
42.
The purpose of this study was to determine normal, mean quadriceps angles (Q angles) for college-aged men and women, and to compare Q angles measured in the supine and the standing positions. The Q angles of 269 men and 257 women were measured in both positions by use of a specially modified goniometer. The mean Q angle for men was 12.7 degrees in the supine position and 13.6 degrees in the standing position; for women the mean Q angle was 15.8 degrees in the supine position and 17.0 degrees in the standing position. All of these differences were statistically significant. We calculated the incidence of an abnormally high Q angle, and will discuss the implications of our findings. 相似文献
43.
44.
J.G. Francis 《Anaesthesia》1992,47(7):630-630
45.
Six numerical integration algorithms based on linear and log trapezoidal methods as well as four cubic-spline methods were proposed for estimation of area under the curve (AUC). These six different algorithms were implemented using IMSL/IDLTM command language and evaluated using data simulated under five different dosing conditions and two different sampling conditions. Comparisons between AUC estimations using these six different algorithms and the theoretical results were made in terms of both overall AUC values and the superimposability of the concentration-time profiles. In well designed studies with ample data points, the algorithm based on IMSL/IDLTM function CSSHAPE with concavity preservation gave the best performance. In contrast, when the frequency of blood collection was limited, the algorithm based on the log trapezoidal rule proved to be stable with reasonable accuracy, and is recommended as the practical method for numerical interpolation and integration in pharmacokinetic studies. Algorithms based on the combination of the log trapezoidal rule and cubic-spline methods using IMSL/IDLTM function CSSHAPE can be developed to enhance overall performance. 相似文献
46.
Nelson T Yamagata Bruce L Miller Duncan McBride Linda Chang Francis Chiang Diana Nikas Diane Osborne Steven D Buchthal 《Journal of neuroimaging》1994,4(1):23-28
The chemical characteristics of 10 neoplastic and 11 infectious brain masses were studied by in vivo 1H magnetic resonance spectroscopy. In tumors, peak height ratios of n-acetyl-L-aspartate to choline were decreased compared to those in normal brain tissue and infectious masses (p < 0.02), but the ratios in normal brains and those with infections did not differ. N-acetyl-L-aspartate—to-creatine/phosphocreatine ratios were significantly lower in infectious masses and tumors compared to normal brain tissue (p = 0.003). However, in progressive multifocal leukoencephalopathy, N-acetyl-L-aspartate appeared relatively unchanged. Lactate was greater than choline in 9 of 11 brains with infection, 0 of 14 control brains, and 1 of 10 tumors. Lactate-to-choline ratios were significantly elevated in infectious masses compared with tumors (p < 0.01). 1H magnetic resonance spectroscopy is promising for the noninvasive diagnosis of focal brain masses. 相似文献
47.
48.
Raymond Dalgleish Timothy Francis Matthew J Beckman 《Journal of orthopaedic research》2006,24(7):1571-2; author reply 1572-4
49.
R I Colebunders A Greenberg P Nguyen-Dinh H Francis N Kabote L Izaley F Davachi T C Quinn P Piot 《AIDS (London, England)》1987,1(3):151-153
In July 1986, a provisional clinical case definition of AIDS in children, developed by the World Health Organization (WHO) for surveillance purposes in Africa, was tested on 159 patients hospitalized in the Department of Pediatrics at Mama Yemo Hospital, Kinshasa, Zaire. Twenty-one (13%) of these children were seropositive for HIV. In this population, the clinical case definition of pediatric AIDS was found to be fairly specific (87%) but lacked sensitivity (35%). The positive predictive value for HIV seropositivity was 25%. This study suggests that it is more difficult to define AIDS clinically in children than in adults and that the utility of the proposed WHO clinical case definition for pediatric AIDS for surveillance of children's AIDS in Africa is limited. 相似文献
50.
The xanthine oxidase catalysed release of superoxide free radicals (O2-) from endogenous hypoxanthine was determined in homogenates of synovium obtained from three groups of patients, those undergoing primary or revision total hip replacement (THR) for osteoarthritis and those undergoing arthroscopy of the knee for semilunar disc injuries. The concentrations of hypoxanthine in homogenates obtained during THR were found to be significantly higher than those in the group with semilunar disc injuries. The results suggest that there is a greater predisposition to free radical release and tissue damage in osteoarthritis. 相似文献