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181.
The high-pressure Diels-Alder reaction of N-carbomethyoxypyrroles and phenyl vinyl sulfone affords versatile intermediates for the palladium-catalyzed preparation of new epibatidine analogues. Structure-activity relationships of new epibatidine analogues are presented. High affinities of Ki = 0.81 and 2.6 nM for the [3H]-cytisine rat brain nicotinic acetylcholine binding sites were found for the 5-pyrimidinyl and the 5-(2-amino)-pyrimidinyl epibatidine analogues, respectively.  相似文献   
182.
Health status measurement in Toxic Oil Syndrome   总被引:1,自引:0,他引:1  
Toxic Oil Syndrome (TOS) is a previously unreported condition which affected more than 20,000 people in Spain in 1981 and whose natural history is unknown. In 1993-94, a stratified random sample of 1400 survivors was drawn to measure their health status through clinical examination and their self-perception of well-being through the Nottingham Health Profile Questionnaire (NHPQ). Two-thirds of the sample population responded; indirect estimates suggest that selection bias was limited. Clear and intermediate signs of neuropathy were found in one-fifth and one-half of the patients, respectively. One-fourth and one-sixth showed some degree of scleroderma and contractures. All conditions were more frequent in women than in men and in age >50 than in younger ages. Although no concurrent control group was included in the study, prevalences of these conditions are well above expectations and are largely attributable to TOS. NHPQ scores increased with age in both sexes up to age 50, after which they reached a plateau (with values around 48 in men and 62 in women). Scores were associated to the occurrence of peripheral neurological changes, contractures, and scleroderma-like conditions. A multivariate analysis indicated age, sex, and severity of neurological conditions as major determinants of the NHPQ scores. This overall pattern of findings is peculiar to TOS and differs from the typical post-disaster nonspecific syndrome.  相似文献   
183.
BACKGROUND: Pathological gambling is becoming an increasing problem in the United States as the number of legalized gambling establishments grows. To examine vulnerability to pathological gambling, we estimated the familial contributions (i.e. inherited factors and/or experiences shared by twin siblings during childhood) to DSM-III-R pathological gambling symptoms and disorder. METHODS: Data were obtained from a telephone interview performed in 1991-92 utilizing the Diagnostic Interview Schedule Version III-Revised. Interviews were administered to 6718 members of the nationally distributed Vietnam Era Twin Registry of male-male monozygotic and dizygotic twin pairs who served in the military during the Vietnam era. RESULTS: Inherited factors explain between 35% (95% CI: 28%, 42%) and 54% (95% CI: 39%, 67%) of the liability for the five individual symptoms of pathological gambling behavior that could be estimated statistically. In addition, familial factors explain 56% (95% CI: 36%, 71%) of the report of three or more symptoms of pathological gambling and 62% (95% CI: 40%, 79%) of the diagnosis of pathological gambling disorder (four or more symptoms). CONCLUSIONS: Familial factors have an important influence on risk for pathological gambling behavior. The increasing access to legalized gambling is likely to result in a higher prevalence of pathological gambling behavior among individuals who are more vulnerable because of familial factors.  相似文献   
184.
Directed neuronal migration contributes to the formation of many developing systems, but the molecular mechanisms that control the migratory process are still poorly understood. We have examined the role of heterotrimeric G proteins (guanyl nucleotide binding proteins) in regulating the migratory behavior of embryonic neurons in the enteric nervous system of the moth, Manduca sexta. During the formation of the enteric nervous system, a group of approx. 300 enteric neurons (the EP cells) participate in a precise migratory sequence, during which the undifferentiated cells populate a branching nerve plexus that lies superficially on the visceral musculature. Once migration is complete, the cells then acquire a variety of position-specific neuronal phenotypes. Using affinity-purified antisera against different G protein subtypes, we found no apparent staining for any G protein in the EP cells prior to their migration. Coincident with the onset of migration, however, the EP cells commenced the expression of one particular G protein, Go alpha. The intensity of immunostaining continued to increase as migration progressed, with Go alpha immunoreactivity being detectable in the leading processes of the neurons as well as their somata. The identity of the Go alpha-related proteins was confirmed by protein immunoblot analysis and by comparison with previously described forms of Go alpha from Drosophila. When cultured embryos were treated briefly with aluminium fluoride, a compound known to stimulate the activity of heterotrimeric G proteins, both EP cell migration and process outgrowth were inhibited. The effects of aluminium fluoride were potentiated by alpha toxin, a pore-forming compound that by itself caused no significant perturbations of migration. In preliminary experiments, intracellular injections of the non-hydrolyzable nucleotide GTP gamma-S also inhibited the migration of individual EP cells, supporting the hypothesis that G proteins play a key role in the control of neuronal motility in this system. In addition, once migration was complete, the expression of Go alpha-related proteins in the EP cells underwent a subsequent phase of regulation, so that only certain phenotypic classes among the differentiated EP cells retained detectable levels of Go alpha immunoreactivity. Thus Go may perform multiple functions within the same population of migratory neurons in the course of embryonic development.  相似文献   
185.
OBJECTIVES: To assess the impact of HIV counselling and testing on HIV seroconversion and incidence of reported sexually transmitted diseases (STDs) among male factory workers in Harare, Zimbabwe. DESIGN: Prospective, observational study among men recruited to participate in a future workplace based AIDS prevention intervention. METHODS: Participants provided STD histories and blood for HIV antibody testing at enrolment and six month intervals during visits to factories. Participants received HIV test results, post test counselling, and free STD services at the project clinic. RESULTS: Between March 1993 and June 1995, 2,414 men were enrolled with 85% follow up. Overall HIV sero-incidence was 2.60 per 100 person-years; the incidence of reported STDs was 10.19 per 100 person-years. Men who obtained their HIV test results had significantly higher HIV sero-incidence and incidence of reported STDs compared to men who did not obtain their results (IRRs: 1.87, 3.47, respectively). Among men who obtained their HIV test results, a non-significant 40% decrease in HIV sero-incidence was observed after obtaining test results compared to before obtaining results (p = 0.18). The incidence of reported STDs, however, increased by 30% after obtaining HIV test results (p = 0.10). CONCLUSIONS: Decreased HIV sero-incidence in the face of increased reported STD incidence suggests that timely treatment of STDs may decrease the risk of acquiring HIV even in the absence of behaviour change. In populations with high rates of HIV and STDs, the greatest benefit of HIV counselling and testing may be achieved by simultaneously offering STD screening and treatment services.  相似文献   
186.
The possibilities of using solid-phase microextraction to determine residues of pesticides in honey have been examined. For this purpose, three types of fiber have been assayed: polyacrylate of 85 microns thickness, and polydimethylsiloxane of 7 and 100 microns thickness. They have been applied to the extraction of 21 pesticides of different chemical families. The effects of the temperature, extraction time and ionic strength on the microextraction have been studied, proposing the most adequate for each fiber. Under optimized conditions, precision, intervals of linearity and detection limits were evaluated.  相似文献   
187.
Myocardial infarction occurring in young people with angiographically normal coronary arteries is well described but the pathophysiology of this condition remains unknown. Coronary artery spasm in association with thrombus formation and minimal atheromatous disease or spontaneous coronary artery dissection are possible causes. Two young men presented with severe chest pain after acute alcohol intoxication and each sustained an extensive anterior myocardial infarction. Investigations including intravascular ultrasound showed no evidence of atherosclerotic coronary artery disease. Coronary artery spasm associated with acute alcohol intoxication as well as prothrombotic state and endothelial damage related to cigarette smoking may be mechanisms leading to acute myocardial infarction in these cases. Acute myocardial infarction occurs in young persons with normal coronary arteries and the diagnosis should be considered in young patients presenting with severe chest pain, particularly those abusing cocaine or alcohol, so that reperfusion therapy can be initiated promptly.  相似文献   
188.
Using dog liver membranes we observed that [125I]HEAT ((+/-)-beta-([125I]iodo-4-hydroxyphenyl)-ethyl-aminomethyl-tetralone) binds with high affinity (KD 97 pM) to a discrete number of sites (Bmax 40 fmol/mg protein) with the pharmacological characteristics expected for alpha 1-adrenoceptors. Such sites were inactivated by pretreatment with chloroethylclonidine. Binding competition experiments indicated the following order of potency: (a) for agonists: oxymetazoline > epinephrine > or = norepinephrine > methoxamine and (b) for antagonists: WB4101 > or = 5-methyl-urapidil = prazosin > or = benoxathian > or = (+)-niguldipine > phentolamine. Northern analysis indicated that total RNA isolated from dog liver hybridized with an alpha 1c selective probe (bovine brain). The orders of potency for agonists and antagonists, their Ki values and the Northern analysis suggest that dog liver expresses alpha 1A-adrenoceptors.  相似文献   
189.
BACKGROUND: Growth retardation has been reported in children with chronic inflammatory bowel disease, especially in those with Crohn's disease. Most of these studies concern adolescent patients. METHODS: The growth of 47 prepubertal children (20 boys and 27 girls, mean age at diagnosis 7 years) with inflammatory bowel disease was studied at Tampere University Hospital, Department of Paediatrics. The mean height and height velocity standard deviation scores were calculated at diagnosis and, after that, yearly. The cumulative doses of oral and rectal prednisone per year were calculated. The severity of the disease was scored. The statistical analysis was carried out using the analysis of variance for repeated measurements. RESULTS: During the year preceding the diagnosis, children with inflammatory bowel disease had grown more slowly than their healthy peers. At diagnosis, they were slightly shorter as a group than are healthy children. During treatment and follow-up the mean height velocity of children with inflammatory bowel disease increased (change in the mean height velocity standard deviation scores from -0.84 to +1.08), normalizing the mean heights of these children compared with those of their healthy peers (change in the mean height standard deviation scores from -0.32 to +0.05). In the analysis of covariance, the poorest growth was seen in children with Crohn's disease, scored as severe, and the best growth in children with mild ulcerative colitis. No difference was seen in groups with or without prednisone treatment. CONCLUSIONS: Growth retardation is an important sign of chronic inflammatory bowel disease in prepubertal as well as adolescent children. During treatment, increasing growth velocity brings these children as a group to normal heights for age and sex.  相似文献   
190.
BACKGROUND: The ideal temperature for blood cardioplegia administration remains controversial. METHODS: Fifty-two patients who required elective myocardial revascularization were prospectively randomized to receive intermittent antegrade tepid (29 degrees C; group T, 25 patients) or cold (4 degrees C; group C, 27 patients) blood cardioplegia. RESULTS: The two cohorts were similar with respect to all preoperative and intraoperative variables. The mean septal temperature was higher in group T (T, 29.6 degrees +/- 1.1 degrees C versus 17.5 degrees +/- 3.0 degrees C; p < 0.0001). After reperfusion, group T exhibited significantly greater lactate and acid release despite similar levels of oxygen extraction (p < 0.05). The creatine kinase-MB isoenzyme release was significantly lower in group T (764 +/- 89 versus 1,120 +/- 141 U x h/L; p < 0.04). Hearts protected with tepid cardioplegia demonstrated significantly increased ejection fraction with volume loading, improvement in left ventricular function at 12 hours, and decreased need for postoperative inotropic support (p < 0.05). The frequency of ventricular defibrillation after cross-clamp removal was lower in this cohort (p < 0.05). There were no hospital deaths, and both groups had similar postoperative courses. CONCLUSIONS: Intermittent antegrade tepid blood cardioplegia is a safe and efficacious method of myocardial protection and demonstrates advantages when compared with cold blood cardioplegia in elective myocardial revascularization.  相似文献   
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