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81.
Journal of Thrombosis and Thrombolysis - To study whether a diagnosis of cancer affects the clinical presentation and outcomes of patients with pulmonary embolism (PE). A retrospective analysis was...  相似文献   
82.
AIDS and Behavior - This randomized controlled trial tested the efficacy of a multi-session, evidence-based, lay counselor-delivered transdiagnostic therapy, the Common Elements Treatment Approach...  相似文献   
83.
The long-term prognosis of paroxysmal ventricular tachycardia (PVT) complicating acute myocardial infarction remains unevaluated. Significant ventricular arrhythmia in the patient after infarction is said to carry a poor prognosis with regard to survival. To evaluate these two important aspects of myocardial infarction in man, 56 patients with documented myocardial infarction had Holter monitoring performed during the initial 24 hours and prior to hospital discharge. In 38 of the 45 survivors, Holter monitoring was repeated an average of 19 months after infarction. There were eight cardiac deaths during follow-up. Data analysis revealed that of 18 patients with PVT during the acute phase, one died during follow-up and 17 survived long-term. Even though the incidence of complex PVCs prior to hospital discharge and at long-term follow-up was higher in patients with PVT during the acute phase than in those without PVT, survival appeared unaffected. Thus, PVT during the acute phase of myocardial infarction and complex PVCs at the time of hospital discharge are not incompatible with long-term survival.  相似文献   
84.
In vitro, crocidolite asbestos toxicity to macrophages is mediated by the production of reactive oxygen metabolites. We examined whether exposure of macrophages to crocidolite asbestos induced lipid peroxidation as measured by the thiobarbituric acid assay. When elicited mouse peritoneal macrophages were exposed to crocidolite, a dose- and time-dependent increase in lipid peroxidation breakdown products accompanied cell death. Superoxide dismutase plus catalase or deferoxamine prevented both lipid peroxidation and loss of viability caused by crocidolite. We tested whether crocidolite-induced lipid peroxidation was causally responsible for cell death. Macrophages were not killed by crocidolite when incubated with 10 mM 3-aminobenzamide. The level of thiobarbituric acid-reactive material was the same, however, for cells incubated with crocidolite in the presence or absence of 3-aminobenzamide. When macrophagaes were pretreated for 24 h with 25 microM vitamin E and then incubated with crocidolite, no thiobarbituric acid-reactive products were detected. Vitamin E, however, did not prevent crocidolite cytotoxicity. These results suggest that exposure of macrophages to crocidolite asbestos produces lipid peroxidation as measured by thiobarbituric acid-reactive products. This reaction, however, is not directly responsible for irreversible injury in this model system.  相似文献   
85.
Kir6.2 is required for adaptation to stress   总被引:28,自引:0,他引:28  
Reaction to stress requires feedback adaptation of cellular functions to secure a response without distress, but the molecular order of this process is only partially understood. Here, we report a previously unrecognized regulatory element in the general adaptation syndrome. Kir6.2, the ion-conducting subunit of the metabolically responsive ATP-sensitive potassium (K(ATP)) channel, was mandatory for optimal adaptation capacity under stress. Genetic deletion of Kir6.2 disrupted K(ATP) channel-dependent adjustment of membrane excitability and calcium handling, compromising the enhancement of cardiac performance driven by sympathetic stimulation, a key mediator of the adaptation response. In the absence of Kir6.2, vigorous sympathetic challenge caused arrhythmia and sudden death, preventable by calcium-channel blockade. Thus, this vital function identifies a physiological role for K(ATP) channels in the heart.  相似文献   
86.
Previous epidemiologic studies have suggested a weak association between oral contraceptive use and Crohn's disease, specifically Crohn's colitis. To measure a possible etiologic association, 51 women with Crohn's disease who were 18-50 yr old were studied and compared with peer-nominated age- and sex-matched controls. There were no differences between cases and controls with respect to race, religion, marital status, and number of pregnancies. There was no association between oral contraceptive use and Crohn's disease incidence [current use: odds ratio (OR) 0.73, 95% confidence interval (CI) 0.34-1.59; former use: OR 1.80, CI 0.61-5.29; current or former use: OR 1.00, CI 0.46-2.16]. Stratifying by disease location also failed to identify an association. Cigarette smoking was significantly associated with Crohn's disease incidence. Controlling for possible confounding effects of cigarette smoking did not alter the lack of association between oral contraceptive use and Crohn's disease. Similarly, testing for interaction failed to demonstrate any effect modification. Analyzing for duration of current oral contraceptive use or time interval since last use failed to demonstrate a "dose-response" effect. The study was of sufficient size to detect statistical significance for oral contraceptive use for odds ratios of greater than or equal to 2.76. From this community-based matched case-control study, there was no association between oral contraceptive use and Crohn's disease, and women need not be advised to discontinue oral contraceptive use when a diagnosis of Crohn's disease is made.  相似文献   
87.
OBJECTIVE: Decreased physician visits for dyspepsia were predicted with the histamine-2 receptor antagonists (H2RA) release to over-the-counter (OTC) status. The aim of this study was to examine the presentation frequency for dyspeptic complaints before and after the OTC release of the H2RA and the self-reported effectiveness of OTC H2RA. METHODS: Two cross-sectional surveys were used in a community sample. The patients comprised a random age- and sex-stratified sample of 1600 ambulatory adults in 1993 and 1800 in 1997. Self-report, valid mail surveys gathered information on healthcare seeking and gastrointestinal symptoms in 1993 and 1997 and antisecretory use in 1997. RESULTS: Presentation frequency for dyspepsia was 22% in 1993 versus 23.5% in 1997. Only 16% of chronic users of the OTC H2RA obtained complete relief of symptomatic episodes. Use of an OTC H2RA was highly associated with presentation to a physician in the past year. CONCLUSIONS: OTC H2RA infrequently provided the complete relief desired by patients. Presentation frequency to physicians for dyspeptic complaints did not change with availability of H2RA OTC.  相似文献   
88.
Fertility is affected in ulcerative colitis after surgery and in active Crohn's disease. Adverse fetal outcomes are not increased when IBD is quiescent. Active disease at conception increases the risk of adverse fetal outcomes. Most medications for IBD are safe during pregnancy and breastfeeding, with notable exceptions. Active disease is usually more deleterious than maintaining medical therapy.  相似文献   
89.
90.
The rectal gland of elasmobranchs secretes a fluid rich in sodium chloride but the mechanism controlling this secretion is obscure. Interrenalectomy diminishes the rectal gland output of sodium chloride in Raja ocellata. NaK-ATPase of high activity occurs in the rectal gland of R. ocellata, but in the present study no significant difference was found between interrenalectomized and shammed skate.  相似文献   
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