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191.
We have studied the prevalence and the serological profile of HBV, HCV, HDV and HIV infections in 137 Italian subjects addicted to the intravenous use of heroine and correlated the virological findings with sexual behaviour. HBV and HCV viremia were also measured in 114 patients. Anti-HCV was detected in 81% of the addicts, and one or more markers of HBV infection were detected in 62.8% (4.4% were carriers of HBsAg, 58.4% had evidence of past HBV infection and 13.1% of the latter also had HDV markers). Anti-HIV was positive in 23.4%; 26% of those positive for anti-HCV and 4.6% of those positive for HBV markers had no other viral marker: none had only anti-HIV. HBV-DNA was negative in the carriers of HBsAg, and HCV-RNA was not detected in any of the HBsAg carriers who also had circulating anti-HCV. Overall, 34% of the anti-HCV positive addicts had HCV-RNA in their blood. The prevalence of the virus infection correlated with the duration of drug addiction but not with sexual behaviour, and sexual behaviour did not influence the acquisition of any virus. HCV infection was most frequent and probably the first infection to occur, but exposure to HBV was also common despite a low rate of HBsAg carriage. The prevalence of HDV infection was high (50%) in the HBsAg carriers, while the overall prevalence of HIV was lower (23%) than expected. Lack of HBV-DNA and HCV-RNA in carriers of HBV with anti-HCV in serum may indicate that HBV and HCV mutually inhibit their own replication.  相似文献   
192.
Thrombin stimulates cytosolic calcium mobilization and tritiated thymidine incorporation in rat glomerular mesangial cells. This effect may be mediated by a thrombin receptor similar to the receptor found in human platelets. In order to test this possibility, a series of analogues of the thrombin receptor peptide, SFLL-RNPNDKYEPF, was evaluated for their effects on mesangial cells. Analogues of the thrombin receptor peptide containing five, six, seven and 14 amino acids were as efficacious as thrombin with respect to calcium mobilization and thymidine incorporation, although they were significantly less potent. The dissimilarity in potency between thrombin and the thrombin receptor peptides is consistent with the kinetics of the proposed mechanism of action of the enzyme, since the cleavage by thrombin of its receptor results in a tethered ligand which is at a relatively high concentration compared to the free peptides in solution. Those thrombin receptor peptide analogues which showed decreased activity in platelets were tested in mesangial cells. Removal of serine at position one, N-acetylation, or replacement of the phenylalanine at position two with alanine resulted in analogues which were inactive in stimulating mesangial cell proliferation or calcium mobilization. In addition, those analogues which had no stimulatory effects in mesangial cells were not antagonists of SFLLRN-mediated calcium mobilization and thymidine incorporation in mesangial cells.  相似文献   
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A random-digit dialed telephone survey was conducted in a traditionally conservative southern state to determine the level of support for sexuality education in the public schools including support for specific sexuality education topics, the earliest grade level at which each topic should be taught, and the amount of instruction time required for sexuality education in the high schools. Survey data were obtained from 534 South Carolina registered voters in late January/early February 1997. Results demonstrated that most South Carolina registered voters: 1) supported sexuality education in the public schools; 2) supported instruction on a variety of sexuality education topics; 3) supported instruction at all grade levels, especially beginning in middle school; and 4) believed instruction time for sexuality education in the high schools should either remain the same or be increased. In addition, a significant increase in support for sexuality education occurred from the beginning of the survey to the end, suggesting that the instrument itself may have served as an educational tool for respondents. The characteristics of registered voters who supported sexuality education at the beginning of the survey and at the end were examined and compared. These results may assist in the development of educational and marketing strategies designed to build support for school-based sexuality education programs in South Carolina and elsewhere.  相似文献   
195.
The authors describe 9 patients with bipolar affective disorder associated with cerebrovascular lesions. Eight had negative family histories of affective disorders and late age at onset (after age 40) of manic-depressive symptoms. Only one, with positive family history of affective disorders, developed mood swings before age 40. Clinical subtypes of bipolar disorder and patterns of affective cycling in these stroke patients resembled those previously reported in functional bipolar disorder. Five patients had concurrent hyperkinetic movement disorders, and one depressed patient presented with unilateral left-sided parkinsonism that disappeared during a manic switch. In most patients, bipolar affective disorder was associated with right hemisphere lesions that involved subcortical and midline structures. Findings suggest that damage to frontal-basal ganglia-thalamocortical circuits by subcortical vascular lesions may simultaneously provoke disorders of movement and mood regulation.  相似文献   
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All of 16 infants with neonatal meningitis treated during a 30-month period were found to have accompanying ventriculitis at the time of the initial ventricular puncture. Fifteen of these infants were caused by gramm-negative organisms. All infants received antibiotics systemically and intraventricularly via an implanted ventriculostomy reservoir or by direct ventricular injection. Antibiotic concentrations within the ventricular fluid were monitored during chemotherapy; the complications encountered during treatment are discussed. Fifteen infants survived the infection; of these, seven infants were normal at follow-up examinations. In our experience intraventricular chemotherapy as an adjunct to systemic administration of antibiotics has greatly reduced the mortality rate in neonatal meningitis.  相似文献   
198.
The effects of hypothalamic disconnection on body temperature and hypothalamo-pituitary-adrenal activity following acute and repeated exposures to heat were studied. Intact male rats, or animals with complete posterior or anterior hypothalamic disconnection, were exposed to a temperature of 36 degrees C and a relative humidity of 35-45%. In the complete posterior and anterior hypothalamic disconnected rats the basal Tre was higher than that of the intact rats; the rise in Tre following heat exposure was lower in the operated rats than in the intact animals. All the experimental animals, except for those with anterior hypothalamic disconnection, showed a significant inhibition of corticosterone release on exposure to heat for 30 min, but no inhibition was observed in any of the disconnected rats when they were exposed to heat for 120 min. These results suggest that the main stimulus for ACTH release, during the first 30 min of heat exposure, is mediated by a neural input through the posteroir hypothalamus and this is followed by a nerural and/or humoral mechanism which enables the animals to increase their corticosterone secretion.  相似文献   
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