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91.
T M Kim H R Brown S H Lee C V Powell P Bethune N L Goller H T Tran J S Mackay 《Modern pathology》1992,5(3):348-352
A 9-yr-old girl developed delayed acute measles inclusion body encephalitis, which was different from subacute sclerosing panencephalitis (SSPE) in clinical course. Measles virus was demonstrated by electron microscopy, immunohistochemistry, and in situ hybridization. Contrary to the most previous reports, matrix (M) protein was present in the brain, cerebrospinal fluid, and serum and was demonstrated by Western blot analysis and in situ hybridization. The hybridization was performed by a nonradioactive digoxigenin method. 相似文献
92.
Marcos Daccarett MD Gustavo Espinosa MD FACR Fred Rahimi DPM Christopher M. Eckerman DPM Shelley Wayne-Bruton DPM Mark Couture DPM Jason Rosenblum DPM 《The Journal of foot and ankle surgery》2002,41(6):372-378
Dactylolysis spontanea is an idiopathic condition affecting the fifth toe, and sometimes other toes, that is frequently bilateral, with lesions in different stages. Between 1977 and 1999, a total 6000 radiographic studies of the feet were reviewed in a mainly African American population in Chicago, Illinois. After an initial screening based on the Cole criteria, 581 patients were selected and re-examined, and amplification techniques were performed. After reviewing the complementary exams, 102 patients were diagnosed with dactylolysis spontanea or ainhum. Soft-tissue constriction was the most frequently presented radiological sign on the initial screening. Kurtosis at the digit plantar fold and marked rotation of the fifth toe were normal findings in asymptomatic patients. Demographics, comorbidities, and radiological findings were analyzed in the selected population. Associated diseases occurring in these patients appeared to have no specific etiologic correlation with ainhum. African Americans and the dark-skinned population are affected exclusively by this condition, presumably due to the fibrogenic tendency of these individuals. Early diagnosis and accurate staging of ainhum are facilitated by radiological examination of the feet. The findings suggest that this condition is underdiagnosed and overlooked because its low prevalence and variable clinical presentations that might mimic more common etiologies, including localized trauma. 相似文献
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Bioactive stilbenes of Scirpus maritimus 总被引:1,自引:0,他引:1
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96.
M F Powell 《Journal of pharmaceutical sciences》1986,75(9):901-903
In the absence of strong buffer catalysts, the degradation of codeine sulfate (7,8-didehydro-4,5 alpha-epoxy-3-methoxy-17-methylmorphinan-6 alpha-ol sulfate) in aqueous solution is described by the expression kobs = kH+ [H+] + k0 + kHO-[HO-], where kH+ = (3.9 +/- 1.3) X 10(-8) M-1 X S-1, k0 = (2.7 +/- 0.5) X 10(-8) S-1, and kHO- = (5.1 +/- 1.0) X 10(-6) M-1 X S-1 at 80 degrees C. The activation energies associated with these rate constants are 27.7, 21.0, and 28.3 kcal X mol-1, respectively. In the absence of buffer catalysis, codeine sulfate is predicted to have a room temperature shelf life of approximately 44 years between pH 1 and 10, significantly longer than the 1.1 year shelf life of codeine phosphate reported earlier. 相似文献
97.
This study focuses on the injury rates for natural grass and AstroTurf surfaces and the risk factors of game position and type of play. We examined the game-related knee sprains, medial collateral ligament sprains, and anterior cruciate ligament sprains that occurred in the National Football League during the 1980 to 1989 seasons. The findings are controlled for categories of severity (number of games missed due to injury), position, and situation (rushing or passing) at the time of injury. The analysis of the data incorporates epidemiologic techniques associated with incidence density ratios. The data show that there is a statistically significant difference between the higher AstroTurf injury rates for knee sprains. When knee sprains are separated into medial collateral ligament sprains and anterior cruciate ligament sprains, only the anterior cruciate ligament sprains show a statistically significant higher injury rate for AstroTurf. When simultaneous control variables are considered, significantly more knee sprains occurred to backs on rushing plays and linemen on passing plays. When controlling the data for severity, only the Category II injuries (three or more games missed) sustained by linemen on passing plays had statistically significant higher injury rates for the AstroTurf. For medial collateral ligament sprains, only the Category II injuries for linemen on passing plays remain statistically significant. The data for the ACL sprains show statistically significant differences between the injury rate on natural grass and the injury rate on Astro Turf under conditions of special teams play. 相似文献
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Jason N. MacLean Brian J. Schmidt Shawn Hochman 《The European journal of neuroscience》1997,9(12):2702-2711
Whole-cell recordings of lumbar motoneurons in the intact neonatal rat spinal cord in vitro were undertaken to examine the effects of Kmethyl-D-aspartate (NMDA) receptor activation on membrane behaviour. Bath application of NMDA induced rhythmic voltage oscillations of 5.9 ± 2.1 mV (SD) at a frequency of 4.4 ± 1.5 Hz. Amplitude, but not frequency, of the voltage oscillations was membrane potential-dependent. Voltage oscillations could recruit action potentials and/or plateau potentials with or without superimposed bursting. Blockade of synaptic transmission with tetrodotoxin (TTX) sometimes resulted in a loss of oscillatory activity which could then be restored by increasing the NMDA concentration. After application of TTX, the trajectory of NMDA-induced oscillations was similar to the trajectory induced in the presence of intact synaptic networks, although the mean oscillation duration was longer and the oscillation frequency was slower (1.8 ± 1.1 Hz). Current ramps delivered after bath application of NMDA demonstrated bistable membrane properties which may underlie the plateau potentials. Injection of intracellular current pulses could initiate, entrain and terminate individual plateau potentials. The results suggest that membrane depolarization produced by oscillations may activate other intrinsic conductances which generate plateau potentials, thereby providing the neuron with enhanced voltage sensitivity, compared to that produced by NMDA receptor activation alone. These oscillatory events may have a role in the regulation of motor output in a variety of rhythmic behaviours including locomotion. 相似文献