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排序方式: 共有336条查询结果,搜索用时 187 毫秒
81.
Jansen PM; van der Pouw Kraan TC; de Jong IW; van Mierlo G; Wijdenes J; Chang AA; Aarden LA; Taylor FB Jr.; Hack CE 《Blood》1996,87(12):5144-5151
Interleukin (IL)-12 is thought to be a key factor for the induction of interferon gamma (IFN-gamma), a cytokine essential for the lethal effects of endotoxin. We report here on the release of the nonfunctional subunit of IL-12, p40, as well as biologically active heterodimeric IL-12, p70, after administration of a lethal (n = 5) or sublethal (n = 8) dose of live Escherichia coli to baboons. Remarkably, on lethal challenge, peak levels of p40 were observed at 3 hours that were about twofold lower than those elicited after sublethal challenge (2,813 +/- 515 pg/mL v 4,972 +/- 732 pg/mL, P < .05). This disparity was also observed, although to a lesser extent, for IL-12 p70 antigen, of which maximum levels of 91 +/- 47 pg/mL and 151 +/- 41 pg/mL were measured 6 hours after a lethal or sublethal dose of E coli, respectively. Circulating p70 antigen correlated with IL-12 biologic activity (r = 0.869; P < .001). When comparing lethal to sublethal conditions, lower peak levels of IL-12 on lethal E coli sharply contrasted with higher levels of other proinflammatory cytokines, such as tumor necrosis factor (TNF)-alpha, IL-1beta, IL-6, and IL-8 observed in these animals. Lower IL-12 concentrations in the lethal group may have resulted in part from the enhanced production of IL-10, a known inhibitor of IL-12 synthesis in vitro, as peak levels of this cytokine 3 hours postchallenge inversely correlated with peak levels of IL-12, in particular p40 (r = -0.802; P < .01). Contrary to what might be expected if IFN-gamma were solely induced by IL-12, lethally challenged baboons generated threefold more IFN-gamma at 6 hours than those receiving a sublethal dose (P < .05). Moreover, higher levels of IFN- gamma were associated with lower p40/p70 ratios, suggesting that, in agreement with observations in vitro, IFN-gamma may have preferentially upregulated the release of p70 over p40. These data show that IL-12 is released in experimental septic shock in nonhuman primates and suggest that IL-10 and IFN-gamma are involved in the regulation of this release. Furthermore, this study indicates that the systemic release of IL-12 might be essential, but is not likely sufficient, to promote lethal production of IFN-gamma in sepsis. 相似文献
82.
背景和目的:乳酸水平增高与患者的致病率和病死率显著相关.该研究探讨了在危重患者的早期治疗中,监测乳酸水平是否可以改善患者的预后及其效果.方法:将入住ICU时血乳酸水平≥3.0 mmol/L(3.0 mEq/L)的患者随机分为2组,乳酸组以乳酸水平指导治疗,使患者在最初8h内乳酸水平每2h 下降20%以上;对照组仅有基线乳酸水平,不进行乳酸水平监测. 相似文献
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Background: Glycaemic control is a key issue in the care of people with diabetes mellitus (DM). Some studies have suggested a bidirectional relationship between glycaemic control and periodontal disease. Objectives: To investigate the relationship between periodontal therapy and glycaemic control in people with diabetes and to identify the appropriate future strategy for this question. Search strategy: A comprehensive approach was adopted employing handsearching; searching of electronic databases including the Cochrane Oral Health Group’s Trials Register, CENTRAL, MEDLINE, EMBASE, CINAHL, ZETOC, ISI Web of Knowledge and LILACS; contact with appropriate non‐English language healthcare professionals; authors and organizations. The final date for searching for studies was 24 March 2010. Selection criteria: This review studied randomized controlled trials of people with Type 1 or 2 diabetes mellitus (DM) with a diagnosis of periodontitis. Suitable interventions included mechanical periodontal therapy with or without adjunctives and oral hygiene education. Data collection and analysis: The titles and abstracts of 690 papers were examined by two review authors independently. Ultimately, seven studies were included and 19 excluded after full text scrutiny. All trials were assessed for risk of bias. Main results: Three studies had results pooled into a meta‐analysis. The effect for the mean percentage difference in HbA1c for scaling/root planing and oral hygiene (+/? antibiotic therapy) versus no treatment/usual treatment after 3–4 months was ?0.40% (95% confidence interval (CI) fixed effect ?0.78% to ?0.01%), representing a statistically significant reduction in HbA1c (P = 0.04) for scaling/root planing. One study was assessed as being at low risk of bias with the other two at moderate to high risk of bias. A subgroup analysis examined studies without adjunctive antibiotics ?0.80% (one study: 95% CI ?1.73% to 0.13%; P = 0.09), with adjunctive antibiotics in the test group ?0.36% (one study: 95% CI ?0.83% to 0.11%; P = 0.14), and with antibiotics in both test and control groups after 3/4 months ?0.15% (one study: 95% CI ?1.04% to 0.74%; P = 0.74). Authors’ conclusions: There is some evidence of improvement in metabolic control in people with diabetes, after treating periodontal disease. There are few studies available and individually these lacked the power to detect a significant effect. Most of the participants in the study had poorly controlled Type 2 DM with little data from randomized trials on the effects on people with Type 1 DM. 相似文献
85.
The CATIE (Clinical Antipsychotic Trials for Intervention Effectiveness) Schizophrenia Trial was designed to examine fundamental issues about second-generation antipsychotic (SGA) medications (olanzapine, risperidone, quetiapine, and ziprasidone) - their relative effectiveness and their effectiveness compared to a first-generation antipsychotic (FGA), perphenazine. This article reviews these and other findings from this important trial and offers a perspective regarding their meaning for practice and their significance for the advancement of research in psychiatry. The primary outcome measure, time to discontinuation, served as an index of effectiveness and was remarkably short; only 26% of subjects completed the 18-month trial on the medicine to which they were initially randomized. Subjects receiving olanzapine experienced a slightly longer time to discontinuation. Based on this single criterion, olanzapine showed greater effectiveness than the other agents despite its association with significant metabolic disturbance, especially weight gain. Perphenazine unexpectedly showed comparable levels of effectiveness and produced no more extrapyramidal side effects than the other agents. Despite modest prolactin elevation, risperidone was the best-tolerated medication. Ziprasidone was associated with weight loss and with positive impact on lipids and blood glucose. In Phase 2, clozapine demonstrated better effectiveness compared to other SGAs for subjects who discontinued their Phase 1 medication because of efficacy. Olanzapine and risperidone showed greater effectiveness in the tolerability pathway. CATIE secondary outcomes are currently being examined. Improvements in cognition were modest among all the agents in Phase 1, and perphenazine was no less effective in improving cognitive performance than the SGAs. Cost-effectiveness analysis revealed a significant advantage for perphenazine, due to the impact of the high-priced, brand-name SGAs on overall health care costs. 相似文献
86.
BACKGROUND: Recent empirical evidence [Maher, B.A., Manschreck, T.C., Linnert, J., Candela, S., 2005. Quantitative assessment of the frequency of normal associations in the utterances of schizophrenia patients and healthy controls. Schizophrenia Research 78, 219-224] shows that schizophrenia patients produce an elevated rate of normative thought associations in verbal utterances as measured by an objective computerized procedure. An important theoretical question concerns whether such an elevated rate of associative activity is due merely to psychosis, or can it be found in schizotypic subjects with no prior history of psychosis. METHODS: We hypothesized that schizotypic features should be correlated with associative performance, especially the positive symptom-like schizotypic features. The present study examined associative performance in psychometrically-identified schizotypic subjects (n=25) and normal control (n=29) subjects. We studied individual differences in schizotypal personality features in relation to the associative performance index. RESULTS: Level of normative associations was correlated with total schizotypic features, particularly those involving reality distortion and disorganization. Regression analysis revealed higher levels of disorganization features and lower levels of negative schizotypal features uniquely accounted for variation in the associative performance index. Partial correlation analysis suggested that the negative schizotypic features dimension may function as a suppressor variable moderating the relationship between disorganization and level of normative associations. CONCLUSIONS: Disorganization-related schizotypal features among individuals with no prior history of psychosis are correlated with elevated levels of normative associations. This relationship is most likely moderated by negative schizotypic features. These data support the presence of hyperassociative processes in those deemed to be at elevated risk for schizophrenia (or, more broadly perhaps, psychosis). Our findings support the utility of measuring associative performance using an objective measure and suggest that associative performance may be an endophenotype [Gottesman, I., Gould, T., 2003. The endophenotype concept in psychiatry: etymology and strategic intentions. American Journal of Psychiatry 160, 636-645] for schizophrenia. 相似文献
87.
PGF Swift TC Skinner CE De Beaufort FJ Cameron J Åman H‐J Aanstoot L Castaño F Chiarelli D Daneman T Danne H Dorchy H Hoey EA Kaprio F Kaufman M Kocova HB Mortensen PR Njølstad M Phillip KJ Robertson EJ Schoenle T Urakami M Vanelli RW Ackermann SE Skovlund for the Hvidoere Study Group on Childhood Diabetes 《Pediatric diabetes》2010,11(4):271-278
Swift PGF, Skinner TC, de Beaufort CE, Cameron FJ, Åman J, Aanstoot H‐J, Castaño L, Chiarelli F, Daneman D, Danne T, Dorchy H, Hoey H, Kaprio EA, Kaufman F, Kocova M, Mortensen HB, Njølstad PR, Phillip M, Robertson KJ, Schoenle EJ, Urakami T, Vanelli M, Ackermann RW, Skovlund SE for the Hvidoere Study Group on Childhood Diabetes. Target setting in intensive insulin management is associated with metabolic control: the Hvidoere Childhood Diabetes Study Group Centre Differences Study 2005. Objective: To evaluate glycaemic targets set by diabetes teams, their perception by adolescents and parents, and their influence on metabolic control. Methods: Clinical data and questionnaires were completed by adolescents, parents/carers and diabetes teams in 21 international centres. HbA1c was measured centrally. Results: A total of 2062 adolescents completed questionnaires (age 14.4 ± 2.3 yr; diabetes duration 6.1 ± 3.5 yr). Mean HbA 1c = 8.2 ± 1.4% with significant differences between centres (F = 12.3; p < 0.001) range from 7.4 to 9.1%. There was a significant correlation between parent (r = 0.20) and adolescent (r = 0.21) reports of their perceived ideal HbA1c and their actual HbA1c result (p < 0.001), and a stronger association between parents' (r = 0.39) and adolescents' (r = 0.4) reports of the HbA1c they would be happy with and their actual HbA1c result. There were significant differences between centres on parent and adolescent reports of ideal and happy with HbA1c (8.1 < F > 17.4;p < 0.001). A lower target HbA1c and greater consistency between members of teams within centres were associated with lower centre HbA1c (F = 16.0; df = 15; p < 0.001). Conclusions: Clear and consistent setting of glycaemic targets by diabetes teams is strongly associated with HbA1c outcome in adolescents. Target setting appears to play a significant role in explaining the differences in metabolic outcomes between centres. 相似文献
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