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81.
Detectability of breast cancer with magnetic resonance (MR) imaging versus xeromammography was quantitatively compared. MR images were obtained of breasts of 120 women who underwent xeromammography. T1 values were determined for masses larger than 2 cm. Cancer was histologically confirmed in 39 breasts and was considered excluded from 81 due to results of biopsy, cyst aspiration, or sonography or absence of change in xeromammographic findings over time. Images were blindly interpreted by three observers, and results were expressed as receiver operating characteristic curves. Detectability of breast cancer was substantially better with xeromammography than with MR imaging for all observers (P less than .03, 10(-6), and .001). On MR images, spiculation of a mass, distorted architecture, skin thickening, and nipple or skin retraction were specific but relatively insensitive indicators of cancer. Masses with smooth, distinct margins and signal intensity greater than that of fat on T2-weighted images were always benign. Other findings and T1 values were not diagnostically useful. The authors conclude that xeromammography is superior to MR imaging in detection of breast cancer.  相似文献   
82.
Heller  RM; Horev  G; Kirchner  SG; Schaffner  W 《Radiology》1988,166(2):563-567
The epidemic of the acquired immunodeficiency syndrome (AIDS) has affected all geographic regions of the United States. Indeed, it is likely that a majority of U.S. hospitals have cared for patients who are infected with the human immunodeficiency virus (HIV), the virus that causes AIDS. More than 46,000 individuals with HIV infection have fulfilled the strict diagnostic criteria for AIDS (1). All of these patients with AIDS have been seriously ill and have been hospitalized, often multiple times and for prolonged periods. Another, larger group patients with HIV infection has had another form of the disease, the so-called AIDS-related complex. Many of these patients have also spent time in hospitals. An even larger group of individuals has been infected with HIV but has remained asymptomatic to date. Some of these persons have been admitted to hospitals or have received outpatient diagnostic procedures for intercurrent medical or dental complaints that were unrelated to their asymptomatic HIV infection. At the time of their medical evaluation, some of these asymptomatic individuals were known to have a positive HIV antibody test. It is likely, however, that the serologic status of the majority of asymptomatically infected patients was unknown. Thus, by now a very large number of health-care personnel in the United States, including diagnostic radiology staff, have assisted in the care of HIV-infected patients.  相似文献   
83.
The Radiation Oncology Center in Sacramento, California, has developed a procedure for establishing an intraoperative radiation therapy facility in a community practice. The logistics pertaining to personnel, equipment, physical measurements, and quality assurance are presented. Particular emphasis is given to the most effective means of acquiring the large quantity of data needed to ensure a program of acceptable quality.  相似文献   
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85.

Background  

Female sex workers and their clients play a prominent role in the HIV epidemic in India. Systematic data on the outputs, cost and efficiency for HIV prevention programmes for female sex workers in India are not readily available to understand programme functioning and guide efficient use of resources.  相似文献   
86.
Recent studies have indicated that injection-related infections such as abscesses and cellulitis account for the majority of emergency room visits and acute hospitalizations accrued by local injection drug users. The objective of this analysis was to examine the prevalence and correlates of developing an abscess among a cohort of injection drug users in Vancouver and to identify socio-demographic and drug use variables associated with abscesses at baseline. We examined abscesses among participants enrolled in a prospective cohort of injection drug users. Categorical variables were analyzed using the Pearson's chi-square test and continuous variables were analyzed using the Wilcoxon signed rank test. Among 1 585 baseline participants, 341 (21.5%) reported having an abscess in the last six months. In a logistic regression model that adjusted for all variables that were associated with having an abscess at p < 0.1 in univariate analyses, female gender [odds ratio (OR) = 1.7, [95%CI: 1.2 – 2.4]; p = 0.002), recent incarceration (OR = 1.7, [95%CI: 1.3 – 2.2]; p < 0.001), sex trade involvement (OR = 1.4 [95% CI: 1.0 – 2.0]; p = 0.03), frequent cocaine use (OR = 1.5 [95%CI: 1.2 – 2.0]; p = 0.002) and HIV serostatus (OR = 1.5, [95%CI: 1.2 – 2.0]; p = 0.003) were positively associated with having an abscess. Explanations for these associations require further study, and interventions are needed to address this highly prevalent concern.  相似文献   
87.

Background  

Relatively little is known about the incidence of prescribing errors and there has been no work on this in a single specialty ophthalmic hospital. Knowing where and when errors are most likely to occur is generally felt to be the first step in trying to prevent these errors. This study is an attempt in, the setting of an eye hospital, to try to identify and attribute these medication errors.  相似文献   
88.
长期以来,一直存在抗高血压药物是否有致癌作用的争议.自从在年龄>50岁的妇女中使用萝芙碱提取物造成乳腺癌发病率增加的报道后[1],这一争议已持续了30年.Sipahi和同事们最近的研究显示:血管紧张素受体拮抗剂(angiotensin receptor-blockers,ARB)有较高的致癌风险.这一发现再次引发了抗...  相似文献   
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