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11.
12.
Visual function and academic performance   总被引:1,自引:0,他引:1  
Evaluation of 1,910 first-, second-, and third-grade students indicated that visual function and academic performance as measured by reading were not positively related. Visual function tests included visual acuity, muscle balance, preferred eye and hand, color vision, refraction, sensory and motor function, and a writing and drawing task. Academic tests included the Metropolitan Readiness Test, the Cognitive Abilities Test, the Iowa Test of Basic Skills, and the teacher's assessment of reading level. A simple test which can be completed during the office visit and interpreted by the ophthalmologist in the office included drawing, copying, and writing. A segment of this test, the "draw a bicycle test," can be used by an ophthalmologist to demonstrate the difference between vision and performance when examining a child up to third-grade level who is referred because of school failure.  相似文献   
13.
A recombinant Norwalk virus (NV) protein enzyme immunoassay was used to study the age of acquisition of NV IgG in various populations. In London, England, there was little evidence of infection during the first 2 years of life. However, the prevalence of NV IgG rose steadily throughout the period that children attend school, reaching a peak of 70% in the group aged 11–16 years. High levels of maternal antibody were detected in infants aged <3 months. Comparison of the acquisition of antibodies to three strains of human calicivirus in Japanese children in northern Japan indicated that although the majority had experienced infection with strains Japan and UK1 by the age of 12 years, only 22% possessed antibodies to NV. In Australian aborigines NV infection occurs early in life; by the age of 6 years over 90% of children were seropositive. © 1994 Wiley-Liss, Inc.  相似文献   
14.
K G Nickerson  N M Bennett  D Estes  S Shea 《JAMA》1990,264(14):1813-1817
Despite recent gains in admission to medical school and in obtaining junior faculty positions, women remain underrepresented at senior academic ranks and in leadership positions in medicine. This discrepancy has been interpreted as evidence of a "glass ceiling" that prevents all but a few exceptional women from gaining access to leadership positions. We analyzed data from Columbia University College of Physicians & Surgeons, New York, NY, for all faculty hired from 1969 through 1988 and found that the likelihood of promotion on the tenure track was 0.40 for women and 0.48 for men (ratio, 0.82; 95% confidence interval, 0.56 to 1.20); on the clinical track the likelihood of promotion was 0.75 for women and 0.72 for men (ratio, 1.04; 95% confidence interval, 0.56 to 1.94). Additional analysis of current faculty showed that in the academic year 1988-1989 the proportion of women at each tenure track rank at the College of Physicians & Surgeons equaled or exceeded the national proportion of women graduating from medical school, once allowance was made for the average time lag necessary to attain each rank. On the clinical track women were somewhat overrepresented, particularly at the junior rank. National data that describe medical school faculty, which combine tenure and clinical tracks, showed that in 1988 women were proportionately represented at each rank once the lead time from graduation was considered. We conclude that objective evidence shows that women can succeed and are succeeding in gaining promotions in academic medicine.  相似文献   
15.
We investigated changes in community-based agencies following the implementation of the Medicare prospective payment system for hospitals utilizing DRGs (diagnosis-related groups). Data were collected in 1986 and 1987 from 771 community service providers. There were five major findings: 1) hospital discharge planners, nursing homes, and home health agencies experienced DRG effects before other types of community providers studies; 2) the "reach" of DRG impact is widespread; 3) providers report a change in clientele toward a heavier-care client; 4) the impact of DRGs affects the types of services agencies provide; and 5) community providers have experienced a decrease in their ability to refer their clients both to hospitals and to each other.  相似文献   
16.
A procedure for control of variceal bleeding has been described which involves "devascularization" of the distal one third of the esophagus and upper one half of the stomach combined with a Nissen fundoplication performed through a left lateral thoracotomy and an incision in the left diaphragm. Transection of the truncal vagi is required to effectively de vascularize the distal esophagus and, thus, pyloromyotomy or pyloroplasty is added. Six patients who were moderately high risk candidates underwent this procedure for control for persistent hemorrhage; five of these patients were operated on within 48 hours of admission. There was one postoperative mortality. The five survivors have not rebled, and there has been no evidence of encephalopathy or progressive liver deterioration over a mean follow-up of thirteen months.  相似文献   
17.
During the 1980s, as the health care industry experienced what observers have dubbed a revolution, the home health industry also experienced its own transformation. Utilizing three organizational theories (neoinstitutional, resource dependency and population ecology), the authors report on a study of a probability sample of 163 home health agencies (HHAs) that were interviewed in 1986 and again in 1987 on the effects of Medicare policy changes including prospective payment (DRGs). This study tests hypotheses concerning the influence of environmental factors (e.g., state policy and characteristics of the local market) and organizational characteristics of the HHA (e.g., tax status and Medicare reliance) in explaining the propensity of HHAs to be (or become) parts of chains and/or multi-facility systems; and to develop particular types of interorganizational relations. The paper discusses the results in the context of public policy changes and the implications for future research and practice.  相似文献   
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19.
Patients who have had an organ transplant have a need for highly effective contraception. Intrauterine devices, depo-medroxyprogesterone acetate, and implantable etonorgestrel have the highest efficacy combined with the least chance of interaction with antirejection medication regimens. Combined hormonal contraceptives and progestin-only pills are also acceptable methods for patients who do not have other contraindications to their use. Barrier method use should be advocated for any patient who is entering a new sexual relationship and as an adjunct to other methods. Consultation with a gynecologist experienced with the provision of contraceptives to medically complicated patients is advised for all women of reproductive age who have received an organ transplant.  相似文献   
20.
Proliferation of latently infected CD4+ T cells with replication-competent proviruses is an important mechanism contributing to HIV persistence during antiretroviral therapy (ART). One approach to targeting this latent cell expansion is to inhibit mTOR, a regulatory kinase involved with cell growth, metabolism, and proliferation. Here, we determined the effects of chronic mTOR inhibition with rapamycin with or without T cell activation in SIV-infected rhesus macaques (RMs) on ART. Rapamycin perturbed the expression of multiple genes and signaling pathways important for cellular proliferation and substantially decreased the frequency of proliferating CD4+ memory T cells (TM cells) in blood and tissues. However, levels of cell-associated SIV DNA and SIV RNA were not markedly different between rapamycin-treated RMs and controls during ART. T cell activation with an anti-CD3LALA antibody induced increases in SIV RNA in plasma of RMs on rapamycin, consistent with SIV production. However, upon ART cessation, both rapamycin and CD3LALA–treated and control-treated RMs rebounded in less than 12 days, with no difference in the time to viral rebound or post-ART viral load set points. These results indicate that, while rapamycin can decrease the proliferation of CD4+ TM cells, chronic mTOR inhibition alone or in combination with T cell activation was not sufficient to disrupt the stability of the SIV reservoir.  相似文献   
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