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41.
The fibrinolytic system involves a series of enzymatic reactions that results in the conversion of the proenzyme, plasminogen, into the trypsin-like lytic enzyme, plasmin. The major physiologic target of plasmin is fibrin. Free plasmin in plasma is a nonspecific lytic enzyme that will degrade other proteins such as fibrinogen and coagulation factors V and VIII. Plasmin and activators of plasminogen also play a role in ovulation, embryo implantation, tissue remodeling, and inflammation.  相似文献   
42.
The quality of the treatment of finger fractures by Accident and Emergency Department staff has been prospectively assessed during a six-month period. 678 finger fractures were seen in the A. & E. Department. The primary treatment of 624 of these was performed by the A. & E. staff, but in 169 of these (27%), the treatment was inappropriate. Most management errors were elementary; they included failure to prescribe antibiotics for compound fractures, failure to reduce displaced fractures accurately and unsatisfactory splintage. It is recommended that all finger fractures should be assessed and treated by surgeons with training in the management of hand injuries.  相似文献   
43.
To determine if chronic haloperidol (3.0 mg/kg per day) or chlorpromazine (4.2 mg/kg per day) treatment alters central beta-endorphin metabolism, haloperidol and chlorpromazine were perfused via Alzet minipumps into male Sprague-Dawley rats for 8 days. Crude twice-washed membranes, purified synaptic plasma membranes and Golgi-enriched membranes, respectively, were isolated from rat brains and time course incubated with beta-endorphin. All samples were analyzed by high resolution, reversed-phase high performance liquid chromatography. The half-lives of beta-endorphin for animals treated with haloperidol or chlorpromazine were not statistically different from control animals at the crude washed membranes. At the purified synaptic plasma membranes, however, the half-lives of beta-endorphin from haloperidol (t 1/2 = 45.1 min)- and chlorpromazine (t1/2 = 47.0 min)-treated animals were significantly decreased as compared to the control animals (t1/2 = 78.0 min). The half-life of beta-endorphin at the Golgi-enriched membranes was increased for haloperidol (t1/2 = 112.3 min) and chlorpromazine (t1/2 = 103.0 min)-treated animals when compared to control animals (t1/2 = 80.2 min). The findings indicate a differential effect of the dopamine receptor antagonists haloperidol and chlorpromazine on the extracellular fate at the synaptic plasma membranes of beta-endorphin and the intracellular processing at the Golgi-enriched membranes in vitro.  相似文献   
44.
We evaluated the diagnostic performance of 15 clinical case definitions for pertussis in 233 patients who developed acute respiratory illness during community outbreaks in Wisconsin and Delaware. Using results from culture (Regan-Lowe media) and serology (Ig-class-specific ELISA) as diagnostic standards, cough for greater than or equal to 14 days was both sensitive (84 per cent-92 per cent) and specific (63 percent-90 per cent) in identifying patients with pertussis. This definition may be useful in monitoring pertussis outbreaks and for investigating contacts of culture-positive cases.  相似文献   
45.
Background. Little is known about preload-dependent cardiac function after brain death (BD) and subsequent graft preservation.

Methods. A validated model of BD in rabbits was developed and myocardial performance was studied after BD induction and 1 hour of subsequent global hypothermic ischemia using a validated rabbit model and an isolated work-performing heart preparation.

Results. Significant decreases in stroke work, left ventricular contractility, and left ventricular relaxation were observed 2 hours after BD. After global hypothermic ischemia, significant decreases in stroke work, left ventricular contractility, and left ventricular relaxation were observed in the BD group compared with controls. Cardiac output and coronary flow were also significantly decreased in BD hearts compared with controls. Creatine kinase release was increased by 32.5% in BD hearts compared with controls.

Conclusions. In a rabbit model, BD combined with global hypothermic ischemia causes a significant decrease in left ventricular function compared with global hypothermic ischemia. This dysfunction may be attributed to a significant decrease in coronary flows in BD hearts.  相似文献   

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AIMS: To determine the most appropriate regression models to use when assessing risk factors for severe hypoglycaemia and to investigate the impact of model misspecification and its clinical implications. METHODS: A total of 1229 children with Type 1 diabetes (mean age 11.7 years sd 4.1), of which 605 (49.2%) were males, were studied. Prospective assessment of severe hypoglycaemia (an event leading to loss of consciousness or seizure) was made over the 9-year period, 1992-2001. Patients were seen every 3 months and episodes of hypoglycaemia along with clinical data were recorded. Over 70% of children never experienced a severe hypoglycaemic event. Data were analysed using the Poisson regression, negative binomial, zero-inflated Poisson (ZIP) and zero-inflated negative binomial (ZINB) models. The over-dispersion and likelihood ratio statistics were calculated and the analytical methods compared. RESULTS: The Poisson regression model did not fit the data well. The negative binomial and the zero inflated Poisson and negative binomial models fitted the data better than Poisson. CONCLUSIONS: The commonly used Poisson regression models to analyse hypoglycaemia epidemiology may lead to biased parameter estimates and incorrect determination of risk factors for hypoglycaemia. We recommend the use of the negative binomial or zero inflated models to examine any risk factors associated with severe hypoglycaemia. Careful consideration must be given to the interpretation of hypoglycaemia surveys and their analysis.  相似文献   
49.
BACKGROUND: Neuroimaging reports of increases in signal hyperintensities in white and deep gray matter and other work indicate that there might be an inflammatory response in affective disorders. METHODS: The microvascular immunoreactivity of intercellular adhesion molecule-1 and vascular cell adhesion molecule-1 was measured with image analysis in postmortem tissue from the anterior cingulate cortex (ACC) and dorsolateral prefrontal cortex (DLPFC) from 15 unipolar and 15 bipolar subjects and compared with each other and with 15 subjects with schizophrenia and 15 control subjects. RESULTS: Intercellular adhesion molecule-1 immunoreactivity in gray and white matter of the ACC in bipolar subjects was increased compared with control subjects (gray: p =.001; white: p <.001) and schizophrenic subjects (gray: p =.016; white: p =.025) and modestly increased in white matter compared with unipolar subjects (p =.049). No such differences were found in the DLPFC. CONCLUSIONS: These findings are consistent with the presence of an inflammatory response in the ACC in bipolar disorder.  相似文献   
50.
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