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31.
Localization of a gene for otosclerosis to chromosome 15q25-q26   总被引:5,自引:0,他引:5  
Among white adults otosclerosis is the single most common cause of hearing impairment. Although the genetics of this disease are controversial, the majority of studies indicate autosomal dominant inheritance with reduced penetrance. We studied a large multi- generational family in which otosclerosis has been inherited in an autosomal dominant pattern. Five of16 affected persons have surgically confirmed otosclerosis; the remaining nine have a conductive hearing loss but have not undergone corrective surgery. To locate the disease- causing gene we completed genetic linkage analysis using short tandem repeat polymorphisms (STRPs) distributed over the entire genome. Multipoint linkage analysis showed that only one genomic region, on chromosome 15q, generated a lod score >2.0. Additional STRPs were typed in this area, resulting in a lod score of 3.4. STRPs FES (centromeric) and D15S657 (telomeric) flank the 14. 5 cM region that contains an otosclerosis gene.   相似文献   
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The effects of long-term administration of the putative neuroprotective agents pergolide and (-)-deprenyl was assessed by studying 3H-mazindol and 3H-spiperone binding at 12 and 20 months in the major dopamine brain regions. Male Wistar rats were treated from 3 to 20 months, together with their respective untreated and saline injected control groups. The main findings were: 1) there was a decrease in both 3H-mazindol and 3H-spiperone binding with age between 12 and 20 months; 2) there were no differences at 20 months between the pergolide or the (-)-deprenyl treated groups and their controls, thus providing no evidence for long-term neuroprotection; and 3) there was a marked decrease in 3H-mazindol binding in the injected controls compared with the untreated controls at both 12 and 20 months. This raises the possibility that mild chronic stress may accelerate the aging of the dopamine system.  相似文献   
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In mid-1988 a postal survey was conducted of one in five general practitioners in England and Wales, to examine their contact with people with human immunodeficiency virus (HIV) infection, with the acquired immune deficiency syndrome (AIDS) or with worries about HIV infection or AIDS. The response rate was 63.9%. Of the 3339 respondents 22.7% knew of an asymptomatic HIV positive patient within their practice, 5.4% knew of a symptomatic HIV positive patient and 6.4% knew of a patient with AIDS. The estimated annual rate for HIV-related consultations in general practice (including consultations with the 'worried well') was 6.5 per 1000 population. HIV-related consultations occurred more frequently in the four Thames health regions than elsewhere. A sample of 715 practitioners who reported consultations with HIV infected people or those with worries about infection in the previous month, were invited to keep a diary of HIV-related consultations for one week. The response rate to the diary was 64%. Nineteen per cent of the 273 consultations recorded in the diaries were initiated by homosexual men, 16.5% by injecting drug users, 10.3% by the sexual partners of people at risk of infection; 42.9% of consultations were not associated with recognized risk factors. The results indicate that general practitioners have substantial contact with patients with HIV infection, with AIDS and with worries about HIV infection or AIDS. This contact is likely to increase, alongside the anticipated spread of HIV infection, with consequent implications for general practice resources.  相似文献   
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Hepatitis delta virus, discovered in 1977, requires the help of hepatitis B virus to replicate in hepatocytes and is an important cause of acute, fulminant, and chronic liver disease in many regions of the world. Because of the helper function of hepatitis delta virus, infection with it occurs either as a coinfection with hepatitis B or as a superinfection of a carrier of hepatitis B surface antigen. Although the mechanisms of transmission are similar to those of hepatitis B virus, the patterns of transmission of delta virus vary widely around the world. In regions of the world in which hepatitis delta virus infection is not endemic, the disease is confined to groups at high risk of acquiring hepatitis B infection and high-risk hepatitis B carriers. Because of the propensity of this viral infection to cause fulminant as well as chronic liver disease, continued incursion of hepatitis delta virus into areas of the world where persistent hepatitis B infection is endemic will have serious implications. Prevention depends on the widespread use of hepatitis B vaccine. This review focuses on the molecular biology and the clinical and epidemiologic features of this important viral infection.  相似文献   
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BACKGROUND: Health promotion activity in general practice has increased greatly since 1990. A large proportion of this work is undertaken by practice nurses. Little is known about patients' views about the providers of health promotion or their views about general practice health promotion clinics. AIM: A study was carried out in 1992 to determine patients' views about the provision of health promotion advice by general practitioners and practice nurses and their views about attending health promotion clinics. METHOD: A postal questionnaire was sent to a random sample of 1750 patients aged 16 years and over from five general practices in south Tyneside. The questionnaire explored patients' preferences regarding health promotion advice from the general practitioner or practice nurse in relation to four areas of lifestyle advice and factors that might encourage patients to attend a health promotion clinic. RESULTS: A response rate of 75% was obtained from 1639 eligible patients. Receiving health promotion advice from either the general practitioner or the practice nurse was the most commonly preferred option expressed by patients overall. The ability of health promotion clinic staff to deal with patients' concerns about their illness and short waiting times were more likely to influence patients' attendance at health promotion clinics than the presence of a general practitioner or practice nurse. CONCLUSION: In the present study, many patients found health advice received from practice nurses and general practitioners equally acceptable. However, it was the ability of health professionals to respond to patients' health concerns in the health promotion clinic rather than the type of health professional running the clinic that was important for patients.  相似文献   
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