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991.
We examined platelet adhesion in thirty human donor livers to determine if the degree of platelet adhesion could predict outcome of transplantation. Wedge liver biopsies were taken at the start of the donor operation (biopsy 1) and 1 hr after reperfusion in the recipient (biopsy 2). Biopsies were stained with a monoclonal antibody against platelet glycoprotein Ib and graded for platelet adhesion. Hematoxylin and eosin-stained sections were examined for polymorphonuclear leukocyte adhesion and necrosis. Platelet adhesion was much more frequent and extensive than expected in biopsy 1. Nine of 30 biopsies showed moderate or high-grade platelet adhesion. Thus in this study endothelial cell damage was present in about one-third of donors before the donor operation. The injury was not detectable by routine microscopic or clinical examination or biochemical tests. The degree of platelet adhesion in biopsy 1 predicted development of PMN adhesion and necrosis in biopsy 2 and postoperative transaminase concentrations and prothrombin times in recipients. During preservation and implantation some livers converted from low to either moderate or high grades of platelet adhesion. The grade of platelet adhesion in biopsy 2 predicted postoperative outcome as measured by transaminase and PT levels. Patients whose platelet grade converted to a higher level during preservation and implantation did not do as well as patients who remained at a low adhesion grade. These findings strongly suggest that the degree of platelet adhesion is an important determinant in assessing outcome and may provide a means of measuring the status of liver allografts prior to transplantation.  相似文献   
992.
Cocaethylene is a pharmacologically active metabolite resulting from concurrent cocaine and ethanol consumption. The effects of cocaine and cocaethylene on extracellular levels of dopamine in the nucleus accumbens, and serotonin in the striatum were characterized in vivo in the anesthetized rat. Both intravenous (3 mumol/kg) and intraperitoneal (44 mumol/kg) routes of administration were used. In addition to monitoring neurotransmitter levels, microdialysate levels of cocaine and cocaethylene were determined at 4-min intervals after intravenous administration, and at 20-min intervals after intraperitoneal administration. Extracellular levels of dopamine in the nucleus accumbens were increased to approximately 400% of preinjection value by both cocaine and cocaethylene when administered intravenously. Cocaine caused a significant increase of striatal serotonin to 200% preinjection value, whereas cocaethylene had no effect. Brain levels of cocaine and cocaethylene after intravenous administration did not differ. After intraperitoneal administration, extracellular levels of dopamine in the nucleus accumbens were increased to 400% of preinjection levels by cocaine, but were only increased to 200% of preinjection levels by cocaethylene, the difference being statistically significant. Serotonin levels were increased to 360% of preinjection levels by cocaine, but only to 175% of preinjection value by cocaethylene. Levels of cocaine attained in brain were significantly higher than those for cocaethylene, suggesting pharmacokinetic differences with the intraperitoneal route. These results confirm in vivo that cocaethylene is more selective in its actions than cocaine with respect to dopamine and serotonin uptake. In addition, route-dependent differences in attainment of brain drug levels have been observed that may impact on interpretations of the relative potency of the reinforcement value of these compounds.  相似文献   
993.
In order to establish the vizcacha meat quality as food, the percentual chemical composition, cholesterol content and values of some fatty acids were determined. Assays were performed using Wistar rats for estimation of Net Protein Utilization (UPN), True Digestibility (TD) and Biological Value (BV). The results obtained were: protein, 23.87 g/100 g; total lipids, 3.74g/100g and a low content of cholesterol of 50 mg/100g. From the analysis of the fatty acids composition it is noticed a remarkable high proportion of insatured C18 fatty acids. The nitrogen availability calculated from UPN studies gave a value of 60.50 +/- 9.7, a TD of 85.00 +/- 13.20 and a BV of 70.60. Considering on the whole the results here obtained and the optimal approval of this product by man, it is inferred that vizcacha meat constitutes a good base for the production of foods suitable to be manufactured as can products. An adequate promotion of this product will be needed for its introduction in new markets.  相似文献   
994.
We have examined the F82Y;C102T variant of Saccharomyces cerevisiae iso-1-cytochrome c using high-resolution proton nuclear magnetic resonance spectroscopy, chemical denaturation, and differential scanning calorimetry. Comparison of proton chemical shifts, paramagnetic shifts, and nuclear Overhauser effects indicates structural changes are localized to the vicinity of position 82. One alteration involves the rearrangement of the side chain of leucine-85. Using many more proton assignments than were available in the initial report [G. J. Pielak, R. A. Atkinson, J. Boyd, and R. J. P. Williams, Eur. J. Biochem. 177, 179-185 (1988)], a second alteration involving an interaction between arginine-13 and tyrosine-82 is observed. The interaction appears to involve a hydrogen bond with the eta-protons of arginine's guanido group acting as donor and tyrosine's phenolic eta-oxygen as acceptor. In spite of this potentially-stabilizing interaction, the free energy of denaturation decreases by approximately 2.4 kcal mol-1. Results are discussed with respect to alterations in the native and denatured states.  相似文献   
995.
To determine the effect of chronic sulfonylurea therapy on islet function in noninsulin-dependent diabetes mellitus (NIDDM), studies were performed in 18 untreated NIDDM patients before and after 12-16 weeks of chlorpropamide therapy. Fasting plasma glucose (FPG) fell with chlorpropamide therapy from 249 +/- 16 to 157 +/- 8 mg/dl (mean +/- SEM; P less than 0.001), and basal insulin increased from 17 +/- 2 to 24 +/- 3 microU/ml (P less than 0.001). The percent change in basal insulin correlated with the pretreatment FPG (r = 0.62; P less than 0.01) and inversely with the change in FPG during chlorpropamide (r = -0.57; P less than 0.025). Thus, patients with the highest pretreatment FPG showed the largest relative increase in basal insulin and the largest fall of FPG with chlorpropamide therapy. In nine patients, arginine-stimulated acute insulin responses (AIR) were studied at each of three plasma glucose (PG) levels both before and during chlorpropamide treatment. AIR at FPG was not different before and during treatment. However, when PG during treatment was matched by glucose infusion to the pretreatment FPG, the AIR was clearly increased during chlorpropamide therapy (176 +/- 65 vs. 49 +/- 11 microU/ml; P less than 0.02). When AIR is plotted against PG for each individual, the slope of the regression line generated (slope of glucose potentiation) is a measure of that patient's islet sensitivity to glucose. The logarithm of the slope of glucose potentiation correlated inversely with FPG (r = -0.92; P less than 0.001). Chlorpropamide treatment increased the slopes of potentiation from 0.26 +/- 0.11 to 1.47 +/- 0.70 (P less than 0.01). We conclude that chronic chlorpropamide therapy augments both basal and stimulated insulin secretion in NIDDM and that this may be an important mechanism of the drug's hypoglycemic effect. The data support the hypothesis that the hyperglycemia of NIDDM is related to islet insensitivity to glucose and that chlorpropamide treatment improves this impairment.  相似文献   
996.
Examining the effects of Oregon's statutory reform excluding personality disordered individuals from the insanity defense, we previously identified a study sample of insanity acquittees, each of whom was given a primary diagnosis of a personality disorder during subsequent evaluation at the state hospital. In the present study we explore the relationship between that diagnosis and the pretrial psychiatric diagnosis presented to the trial court. By reading the forensic mental health evaluations used at trial we found that 50 percent of our study sample of 34 personality disordered patients were diagnosed with psychotic disorders, affective disorders, retardation, and organic brain disorders. In addition to investigating the diagnosis offered as evidence at trial, we performed assessments of 38 mental health reports using published standards for forensic evaluation reports. We found compliance rates in the various categories ranged from 8 to 84 percent with a mean of 45 percent. We question the value of the mental health input to these trials, and believe that the data tend to validate past aspersions of forensic practice.  相似文献   
997.
OBJECTIVES: Latino adolescents in two urban New England areas were surveyed to assess risk of human immunodeficiency virus (HIV) transmission. METHODS: Probability of HIV infection during the previous 6 months was estimated from self-reported sexual contacts, condom usage rates, and number of partners. Teens were also asked to show condoms in their possession to the interviewer to validate self-reports of condom use. RESULTS: Overall, 8% of the 586 respondents were classified as high risk for HIV infection (estimated infection probability greater than .0001), 34% were at moderate risk, and the remaining 58% were classified as not at risk (no sexual activity or needle sharing). Teens who said they had purchased condoms or claimed to have used them recently were more likely than others to have condoms in their possession at the time of the interview. CONCLUSIONS: These estimates suggest that a small percentage of Latino adolescents may be at substantial risk for HIV infection over periods as short as 6 months, that self-reports of recent condom use are strongly related to condom possession, and that questionnaire items regarding condom use at last intercourse are poor surrogates for HIV risk.  相似文献   
998.
A technique of epidural catheterization in rabbits is described. Twelve albino rabbits received a totally implanted epidural catheter system. The system was implanted surgically, and the functioning of the system tested for a period of 3 months. X-ray examinations following epidural contrast injections showed a distribution up to Th4 following 1.5 ml and Th8-9 following 1.0 and 1.25 ml. Epidural injection of lidocaine throughout the study period proved the system to be functioning for all 3 months. Another 12 rabbits were included for the neurotoxicological examinations following epidural catheterization, without any injections (three rabbits), epidural injections of saline (four rabbits) and meptazinol (five rabbits) once a day for 14 days. Histopathological examinations showed a fibrous cocoon, at the tip of the catheter, in all rabbits. In the group of rabbits which did not receive any injections, the cocoon was slightly infiltrated with leukocytes and local depression of the spinal cord was observed in one rabbit. In the saline-injected group this infiltration was more pronounced and in one rabbit it extended into the meninges. Three rabbits showed local depression of the spinal cord and local myelopathy of the white matter in the area adjacent to the cocoon. In the group of rabbits receiving meptazinol, three out of five had local depression and myelopathy of the white matter. In this group these findings were more pronounced. In two rabbits the myelopathy extended transversely through the white matter into the grey matter of the spinal cord. The number of pathological changes in the group receiving meptazinol was significantly higher compared to the control and placebo groups.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
999.
1000.
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