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991.
A series of 431 vision screening records of seniors 55 years of age and older were analysed. Patients were examined by the UCLA Mobile Eye Clinic at two senior centers in the Los Angeles area, between the years 1982 and 1990. Sixty-eight percent of patients were females and 32% were males. The mean (+/-S.D.) age was 69 (+/-7.5) years. Common diagnoses were refractive errors (65.2%) and impaired visual acuity (37.0%). The prevalences of refractive errors were: hyperopia, 24.8%; myopia, 10.4%; presbyopia, 54.1%; and astigmatism, 31.8%. In most patients (94.0%), impaired visual acuity was corrected by spectacles. The prevalence of cataract was 29.5% and age-specific prevalences of cataract increased with age. The prevalences of other eye disorders were as follows: glaucoma, 6.3%; diabetic retinopathy, 1.2%; and macular degeneration, 5.1%. This study highlights the degree of ophthalmic disorders identified by vision screenings in the elderly population in senior centers; our results are consistent with previously reported studies of eye diseases in the elderly.  相似文献   
992.
A 24-year-old woman presented with nystagmus and head tremor. Both were transient and could be executed simultaneously at different frequencies of oscillation. It is unusual for these two movements, which can be voluntary, to occur together. Suspicions of an acquired disease were not confirmed on further investigation using DC-coupled electro-oculography and angular accelerometry, and on an admission by the patient that the nystagmus could be voluntary. Voluntary nystagmus can become semi-automatic and a patient may be able to simulate more than one "involuntary movement" simultaneously yet at different frequencies.  相似文献   
993.
In 1975 an outbreak of group A meningococcal disease began in Seattle, Washington, and cases subsequently were recognized throughout the Pacific Northwest. Nearly one-half of the affected persons were Native Americans; two-thirds were alcohol abusers and/or habitués of skid road communities. In Seattle, group A meningococci colonized asymptomatic persons only if these individuals had contact with skid road (P = .006). The epidemic strain may have spread from American Indians in Manitoba, Canada. Traditional migration routes connect the two populations; asymptomatic American Indians on reservations in Washington carried group A meningococci. Vaccination programs were undertaken in four cities but only after cases occurred. In Seattle, vaccination reached 80% of the target population and was associated with a significant decrease in incidence of the disease, but cases recurred after the program ended. The social habits of skid road communities, combined with the "case-triggering" approach to, and premature termination of, vaccination programs, may have resulted in 56% of regional cases occurring after the start of the vaccination program in Seattle.  相似文献   
994.
On the basis of studies indicating that natural killer (NK) cells of the mouse can selectively kill certain syngenetic, allogeneic, and xenogeneic tumor cells in short-term Cr release assays and that cell lines established in vitro are more sensitive than the corresponding ascites tumor cells passaged in vivo, the kinetics of the modulation to increased sensitivity was studied after in vitro explanation of the A/Sn mouse-derived YAC ascites lymphoma. Sensitivity to NK lysis appeared after 3 weeks of culturing and reached the level of the continuously cultured line after 2 months. With the more sensitive competition assay, a change could be demonstrated as early as 2--24 hours of culture. The expression of the Moloney murine leukemia virus-determined, cell-surface antigen, measured by quantitative absorption with intact cells, increased in parallel with the NK sensitivity. In contrast, the H-2 alloantigen concentration decreased during in vitro culture.  相似文献   
995.
One hundred twenty-seven patients with Hodgkin's disease, Stages III-IV, received total nodal irradiation. Of these, 101 patients were managed primarily by radiation therapy employing the split course sequential segmental radiation technique called the "3 & 2". A dose of 3800-4000 rad is delivered in 2 phases in an overall period of 12 to 13 weeks (TDF 61-64; 1094-1148 rets). For various reasons, the remaining 26 patients received their mantle irradiation to full doses 3800-4000 rad in 4 weeks (TDF 63-66; 1112-1184 rets) without rest periods and a few were irradiated after failing chemotherapy. Of the 101 patients treated between 1969-1974 using the "3 & 2" technique, 2 developed pericarditis (2.0%), none manifested symptomatic pneumonitis (0%), and 3 hypothyroidism )3.0%). The low incidence of severe complications is primarily the result of the technique employed to give total nodal irradiation. The overall incidence of Herpes Zoster was 42% (53/127), and there was a slightly higher incidence when TNI was given following splenectomy.  相似文献   
996.
Proctocolectomy for ulcerative colitis   总被引:3,自引:0,他引:3  
The majority of patients with ulcerative colitis can be managed satisfactorily throughout their lives by medical treatment, but a minority require colectomy. In severe attacks, emergency surgery is often required to save the patient's life. In chronic disease not responding well to medical treatment, elective colectomy will restore the patient to good health. Colectomy is also necessary for certain local complications, such as cancer, severe fistulas, and strictures. Prophylactic colectomy is indicated in patients with long-standing disease in whom there are factors associated with a high risk of developing cancer of the large bowel. For all these indications, it is our opinion that single-stage proctocolectomy is the operation of choice in the great majority of patients. Finally, we consider that the best results are obtained when the physician and the surgeon work together in the closest possible cooperation.  相似文献   
997.
This exploratory study focuses on the association between social support and adolescents' responses to early motherhood. Subjects are 64 Black adolescent mothers in three groups: high school attenders, participants in the Baltimore City Public Schools Infant Parent Program and dropouts from school. Structured interviews are used to assess the young mothers' emotional stress as well as the amounts, sources, and kinds of support available. Self esteem and sense of control were assessed via standardized instruments. Respondents averaged 16.27 years of age when their children were born; at the time of the interview, ages of the mothers ranged form 14 to 19 years. 50.7% had completed school or were enrolled; 66% were working, typically in part time, work study type programs. Of the heads of their households, 40.3% were employed or receiving Social Services payments, 7.7% held technical jobs with the majority in the skilled or unskilled blue collar category. The children ranged in age from 2 months to 2 years. A major finding was that support from individuals is related to a decrease in stress and an increase in self esteem. The results are discussed in relation to the growing body of research documenting the impact of such support on maternal role performance.  相似文献   
998.
The appearance of resistance to a number of hepatotoxins in primary cultures of hepatocytes prepared at various time intervals up to 2 weeks after partial hepatectomy is the major focus in this study. Resistance to the cytocidal effect of aflatoxin B1, 2-acetylaminofluorene, N-hydroxy-2-acetylaminofluorene, methotrexate, or methyl methanesulfonate shows a progressive increase until 48 hr and then returns to the resting level of susceptibility by 2 weeks. The genesis of mutagens from 2-acetylaminofluorene and aflatoxin B1 by S-9 liver fractions shows a decrease from and return to control values after partial hepatectomy that parallels the resistance. The levels of total cellular cytochromes P-450 also decrease following partial hepatectomy and remain from 28 to 36% less than those of controls for at least 1 week. The glutathione and total soluble sulfhydryl ("glutathione") content increase following partial hepatectomy, and the pattern is consistent with a partial role for glutathione in the resistance phenomenon as it relates to 2-acetylaminofluorene. The possible relationship between resistance to the cytocidal effects in vitro and the resistance to inhibition of cell proliferation in vivo during liver carcinogenesis is discussed.  相似文献   
999.
Five patients suffering from periodic affective disorders with short mood-cycles were treated with rubidium chloride, producing peak erythrocyte concentrations between 9 and 13 mmol/l. Loading with rubidium was associated with decreased total body potassium, but red-cell potassium was unchanged. Regular mood-cycling was disturbed, together with the associated body-weight changes. There was a slight extracellular "metabolic" acidosis. Electrolyte concentrations fluctuate abnormally in these patients, and two muscle biopsy specimens had very low potassium contents.  相似文献   
1000.
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