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51.
The syndrome of parainfectious encephalomyelitis evolves from an antecedent infection. Several etiologic agents have been associated with this complication, although the pathogenesis in each instance may prove to be more uniform. Considerable evidence suggests that the syndrome is mediated immunologically. The seven cases reported here were clinically similar, although the infectious etiologies were diverse. Leptospirosis antedated the neurologic syndrome in two cases, and a "viral" illness preceded the other five cases. The evolution of the syndrome was slowly progressive in each case, and six patients had prominent involvement of rhombencephalic structures. The progressive course was reversed rapidly with eventual full recovery in each instance after initiation of corticosteroid therapy. Our experience with these cases coupled with a review of the literature suggests that corticosteroid therapy should be considered in the subacute or chronic cases of parainfectious encephalomyelitis. 相似文献
52.
A new method for evaluating antiarrhythmic drug efficacy 总被引:1,自引:0,他引:1
M Sami H Kraemer DC Harrison N Houston C Shimasaki RF DeBusk 《Canadian Metallurgical Quarterly》1980,62(6):1172-1179
To develop standards for distinguishing antiarrhythmic drug effect from spontaneous variability of premature ventricular complexes (PVCs), 21 males (mean age 56 +/- 8 years) with chronic ischemic heart disease and PVCs underwent symptom-limited treadmill exercise testing and 24-hour ambulatory monitoring before and after 2 weeks of placebo medication. Linear regression analysis was used to describe the relationship between baseline and placebo PVC frequency for various indexes of ventricular ectopic activity and to establish 95% and 99% one-tailed confidence intervals for this relationship within the group of 21 patients. The lower limit of baseline PVC frequency for which the procedure could distinguish a placebo from a true drug response, termed the "sensitivity threshold," was an average frequency of 2.2 PVCs/hour for ambulatory electrocardiographic monitoring and 1.2 PVCs/min for treadmill exercise testing. All patients exceeded the sensitivity threshold on baseline ambulatory ECGs, but only 38% of patients did so on baseline treadmill exercise tests. To establish antiarrhythmic efficacy with 95% confidence, the minimal percent reduction of PVCs between baseline and placebo visits was 68% for treadmill exercise testing and 65% for ambulatory electrocardiography. Although these standards were developed in patients with chronic ischemic heart disease, the model can be used to establish antiarrhythmic drug efficacy in any patient group. 相似文献
53.
Two new methods of activation were developed to graft enzymes on collegen films. They involved chemical modifications of surface groups of collagen either by Woodward's reagent "K" or by EDC, a water-soluble derivative of carbodiimide. EDC was a better coupling agent and a detailed study was conducted with this agent. It could be used either in a global method of activation and coupling, or in a two-step procedure of activation of collagen, followed by spontaneous coupling of enzyme. All enzymes tested were successfully bound: malate dehydrogenase, lactate dehydrogenase, aspartate aminotransferase, urease, creatine kinase, hexokinase. The influence on the yield of grafted enzyme, of pretreatment of films, time and temperature of EDC activation, concentration of EDC and enzyme, protecting agents was studied. Stability of enzyme activity on storage was greatly increased after grafting. A co-grafted dual system creatine kinase/heoxkinase, was achieved which exhibited a good efficiency. A striking renaturing process at 0-4degreesC after thermal denaturation, was observed with hexokinase. 相似文献
54.
12月23日,由三星投影机携手神州数码联合举办“精英影像务实共赢”全国行业巡展最后一站活动在广州结束,同时,整个行业巡展活动也随之画上了一个圆满的句号。据了解,这场声势浩大的渠道推广活动在全国范围内掀起了一场有关“三星投影机”的追捧热潮,三星力推的几款机型获得了广大用户与渠道商的青睐而迅速成长为“投影明星”。 相似文献
55.
Joshua Elliott Meredith Franklin Ian Foster Todd Munson Margaret Loudermilk 《Computational Economics》2012,39(3):219-241
While computable general equilibrium (CGE) models are a well-established tool in economic analyses, it is often difficult
to disentangle the effects of policies of interest from that of the assumptions made regarding the underlying calibration
data and model parameters. To characterize the behavior of a CGE model of carbon output with respect to two of these assumptions,
we perform a large-scale Monte Carlo experiment to examine its sensitivity to base year calibration data and elasticity of
substitution parameters in the absence of a policy change. By examining a variety of output variables at different levels
of economic and geographic aggregation, we assess how these forms of uncertainty impact the conclusions that can be drawn
from the model simulations. We find greater sensitivity to uncertainty in the elasticity of substitution parameters than to
uncertainty in the base-year data as the projection period increases. While many model simulations were conducted to generate
large output samples, we find that few are required to capture the mean model response of the variables tested. However, characterizing
standard errors and empirical probability distribution functions is not possible without a large number of simulations. 相似文献
56.
Abstract Strong businesses are built on teams of people working together to get the job done. The team metaphor is the model on which to base future computing solutions. Applications for communication and routing, information exchange, process management, collaboration, and meetings are discussed. 相似文献
57.
ML Hawkins JJ Wynn DC Schmacht RS Medeiros TR Gadacz 《Canadian Metallurgical Quarterly》1998,64(6):552-6; discussion 556-7
Changes in the management of trauma over the past few years are significantly affecting postgraduate surgical education, with the lack of operative trauma experience being a major concern in some programs. This problem is accentuated in residency programs that obtain their trauma caseload primarily from blunt injury. Our experience over the past 6 years confirms that the growing trend toward nonoperative management of blunt liver and spleen injuries in adults is likely to exacerbate this problem. Blunt trauma admissions to our Level I trauma center increased from 2888 from 1991 through 1993 (group A) to 3587 from 1994 through 1996 (group B). Liver and/or splenic injuries occurred with equal frequency in both groups. Whereas diagnostic peritoneal lavage was used in 26 per cent of group A, its use dropped to 2 per cent in group B as abdominal computerized tomography was used more frequently to evaluate these patients. Nonoperative management increased from 10 per cent of group A to 54 per cent of group B. As a result, therapeutic laparotomies dropped from 85 in group A (58% of patients with liver/splenic injuries) to 74 (35%) in group B and nontherapeutic laparotomies from 48 (33%) to 23 (11%). While the evolution in the management of blunt liver and splenic injuries has resulted in the avoidance of nontherapeutic laparotomies, the operative caseload available to surgical housestaff has been adversely affected. Although the Residency Review Committee has stressed the importance of the critical care management of these patients, the criteria used to evaluate the number of trauma cases in postgraduate surgical education may need to be revised. 相似文献
58.
CONCEPTS AND ASSUMPTIONS of self-in-relation theory of women's development, as proposed by feminist scholars at the Stone Center in Wellesley, Massachusetts, are applied in this article. This theory was used as a framework to guide staff development and mentorship roles of advanced practice nurses. How the theory served to direct these roles and assisted in development of a professional practice model is discussed. Exemplars from the authors' practices and professional practice outcomes after 2 years of theory implementation are presented. 相似文献
59.
Renal transplantation in adults with thrombotic thrombocytopenic purpura/haemolytic-uraemic syndrome
PJ Conlon DC Brennan WW Pfaf WF Finn T Gehr RR Bollinger SR Smith 《Canadian Metallurgical Quarterly》1996,11(9):1810-1814
BACKGROUND: Thrombotic thrombocytopenic purpura/haemolytic-uraemic syndrome (TTP/HUS) is a rare cause of renal failure in adults. There is little data concerning the outcome of adult patients who receive a renal transplant for TTP/HUS: METHODS: We have carried out a survey of 22 transplant centres in the USA to determine the outcome of patients who developed ESRD from TTP/HUS and latter received a renal transplant. RESULTS: Twelve of the 22 centres responded to our inquiry. Seven centres had not transplanted any patients with TTP/HUS, and five centres had transplanted a total of 24 grafts in 17 patients with TTP/HUS: Thirty-three per cent of patients demonstrated definite clinical and pathological evidence of recurrence of TTP/HUS: An additional 16% of patients demonstrated pathological evidence of possible recurrence of TTP/HUS in the absence of clinical manifestations. The overall 1-year graft survival rate was 42% and the 2-year graft survival rate was 35%. In our experience recurrence TTP/HUS was associated with universal graft failure. Although cyclosporin A does occasionally cause a thrombotic angiopathy in patients with no history of TTP/HUS, we found no evidence that it should be avoided in patients with a previous history of ESRD from TTP/HUS who subsequently receive a renal transplant. CONCLUSIONS: TTP/HUS frequently recurres in adults who receive a renal transplant, with a 2-year graft survival rate of 35%. 相似文献
60.
MJ Greenberger RM Strieter SL Kunkel JM Danforth LL Laichalk DC McGillicuddy TJ Standiford 《Canadian Metallurgical Quarterly》1996,173(1):159-165
The role of macrophage inflammatory protein-2 (MIP-2) in bacterial pneumonia was characterized. Mice were challenged with Klebsiella pneumoniae intratracheally, and organs were harvested at 8, 24, and 48 h. Inoculation with K. pneumoniae resulted in the time-dependent expression of MIP-2 mRNA and protein within the lung, which was maximal 48 h after inoculation. Mice were then passively immunized with rabbit anti-murine MIP-2 serum intraperitoneally 2 h before administration of K. pneumoniae. Treatment with anti-MIP-2 serum resulted in a 60% decrease in lung neutrophil (PMNL) influx and a significant increase in K. pneumoniae colony-forming units in both lung and liver homogenates. Finally, treatment with anti-MIP-2 serum decreased early (48-72 h) but not late (after 72 h) survival in animals with Klebsiella pneumonia. This study indicates that MIP-2 is produced during Klebsiella pneumonia and inhibition of MIP-2 bioactivity in vivo results in decreased PMNL influx and lung bacterial clearance in murine Klebsiella pneumonia. MIP-2 is produced during Klebsiella pneumonia and inhibition of MIP-2 bioactivity in vivo results in decreased PMNL influx and lung bacterial clearance in murine Klebsiella pneumonia. 相似文献