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21.
We have used IL-10 gene knockout mice (IL-10T) to examine the role of endogenous IL-10 in the down-modulation of hepatic granuloma formation and lymphocyte responses that occurs in chronic infection with the helminth parasite Schistosoma mansoni. Although IL-10-deficient animals showed 20 to 30% mortality between 8 and 14 wk postinfection, they displayed no alterations in their susceptibility to infection and produced similar numbers of eggs as their wild-type littermates. The IL-10T mice displayed a significant increase in hepatic granuloma size at the acute stage of infection, which was associated with increased IFN-gamma, IL-2, IL-1beta, and TNF-alpha mRNA expression in liver and elevated Th1-type cytokine production by lymphoid cells. Despite developing an enhanced Th1-type cytokine response, the IL-10T mice showed no consistent decrease in their Th2-type cytokine profile. Surprisingly, although granulomatous inflammation was enhanced at the acute stage of infection, the livers of IL-10T mice displayed no significant increase in fibrosis and underwent normal immune down-modulation at the chronic stage of infection. Moreover, the down-modulated state could be induced in IL-10T mice by sensitizing the animals to schistosome eggs before infection, further demonstrating that the major down-regulatory mechanism is not dependent upon IL-10. We conclude that while IL-10 plays an important role in controlling acute granulomatous inflammation, it plays no essential role in the process of immune down-modulation in chronic schistosome infection.  相似文献   
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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   
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Summary The statistical approach to search is a subject which interfaces with many other fields. This work continues a series of papers which studies these relationship with special emphasis on geometric problems in non-sequential search. A targetT is sought using a series of testsX 1,X 2.... From each test there is an observationY i=f(X i , θ), where θ is an unknown parameter andT=T(θ). Spacing theories and the theories of Voronoi regions can be used to represent the solutions to Bayes and entropy-based formulations to the search problem by partitioning the search field intoconsistent regions where the target is known to lie, given the observations. Other examples are from integration where the target is a function. Covering theory is studied and the last section gives a brief comparison with a sequential approach. Read before the Spanish Statistical Society at a meeting organized by the Universidad de Almería on Friday, April 29, 1994  相似文献   
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A numerical method is given for the determination of the input impedance of a thin-wire helix. The problem is approximated by a frequency-dependent matrix equation whose solution is an approximation to the current distribution and is used in a variational expression for the impedance. Experimental and theoretical results for the determination of the resonant frequency are included.  相似文献   
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Food Science and Biotechnology - Chronic diabetes mellitus (DM) can cause liver dysfunction and other complications. As Humulus japonicus is known to have anti-inflammatory and antioxidative...  相似文献   
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People with schizophrenia consistently report normal levels of pleasant emotion when exposed to evocative stimuli, suggesting intact consummatory pleasure. However, little is known about the neural correlates and time course of emotion in schizophrenia. This study used a well-validated affective picture viewing task that elicits a characteristic pattern of event-related potentials (ERPs) from early to later processing stages (i.e., P1, P2, P3, and late positive potentials [LPPs]). Thirty-eight stabilized outpatients with schizophrenia and 36 healthy controls viewed standardized pleasant, unpleasant, and neutral pictures while ERPs were recorded and subsequently rated their emotional responses to the stimuli. Patients and controls responded to the pictures similarly in terms of their valence ratings, as well as the initial ERP components (P1, P2, and P3). However, at the later LPP component (500–1,000 ms), patients displayed diminished electrophysiological discrimination between pleasant versus neutral stimuli. This pattern suggests that patients demonstrated normal self-reported emotional experience and intact initial sensory processing of and resource allocation to emotional stimuli. However, they showed a disruption in a later component associated with sustained attentional processing of emotional stimuli. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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The Taguchi methods have recently become popular in the U.S.A following a realization of their importance in Japanese quality design. This review is an initial attempt to extract the important ideas while drawing on the ‘Western’ experience with response surface methodology and experimental design.  相似文献   
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