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41.
OBJECTIVES: We sought to determine if screening for coronary artery disease (CAD) with stress single-photon emission computed tomography (SPECT) is of value in patients with atrial fibrillation (AF) who do not have symptoms of chest pain or dyspnea. BACKGROUND: Although noninvasive stress testing is often done to screen for CAD in asymptomatic patients with AF and is considered to be appropriate in selected patients, its potential utility has not been demonstrated. METHODS: A retrospective study was conducted of 374 asymptomatic patients with AF referred for the detection of CAD. Mean follow-up was 5.7 +/- 3.8 years. The study group was compared with a control group of 374 asymptomatic age and gender-matched patients without AF. RESULTS: The mean summed stress score (SSS) was not significantly different between AF patients and control subjects (3.6 +/- 5.3 vs. 3.5 +/- 5.9; p = 0.35). Compared with controls, asymptomatic AF patients had similar rates of abnormal SPECT studies (51.6% vs. 48.4%; p = 0.38) and high-risk studies (14.4% vs. 14.4%; p = 1.0). The SSS was a significant predictor of outcome in both AF patients and control subjects. However, total mortality was significantly greater in AF patients (5-year overall mortality 27% vs. 18%, 10-year overall mortality 47% vs. 40%; p < 0.001), and this difference persisted (p = 0.01) after adjusting for multiple clinical variables and the SSS. CONCLUSIONS: Screening for CAD using stress SPECT in asymptomatic AF patients has a yield similar to age- and gender-matched control patients without AF. Although SSS predicts mortality in patients with and without AF, patients with AF have increased total mortality independent of the findings on stress SPECT. These results suggest that factors other than obstructive CAD are responsible for the increased mortality in AF.  相似文献   
42.
Chrysomya megacephala (F.), an Old World calliphorid of considerable public health importance, was first discovered in Brazil in 1977 and is now widely distributed in Latin America. Reports that this species has become established in southern California, and the collection of a specimen in Texas, suggest that C. megacephala may be expanding its range rapidly in North America. The biology and worldwide spread of this pest are reviewed to alert entomologists and public health workers to this growing threat.  相似文献   
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44.
This study provides an overview of the papers emanating from the experimental trial that evaluated a new cognitive rehabilitation program in older adults who were experiencing normal cognitive decline. The main features of the design are summarized, along with evidence that the training produced long-lasting improvement in memory performance, goal management, and psychosocial status. The benefits were attributed to several factors, including the program's emphasis on techniques that promoted efficient strategic processing. Limitations of the program and directions for future research are discussed.  相似文献   
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46.
Two patients with carcinoma of the penis were treated with interstitial radiation. They were cured of their disease for 17 and 21 years respectively and then developed radiation-induced tumours.  相似文献   
47.
Paragangliomas are neuroendocrine tumours and those occurring in the head and neck have well recognized familial association. Retroperitoneal paragangliomas are uncommon and we present two cases of familial malignant retroperitoneal paraganglioma. Review of the literature revealed marked differences in the incidence and malignant potential of familial and non-familial paraganglioma. In contrast to the cases reported here, familial tumours are generally benign, though they may occur at multiple sites. Familial and non-familial paragangliomas may indeed be different disease entities.  相似文献   
48.
With improving neonatal survival for extremely premature babies, the challenge for neonatology is to improve outcome of surviving babies. This review concentrates on best evidence emerging in recent years on prevention of brain damage by early administration of drugs as well as avoidance of induced brain damage by hyperventilation and dexamethasone therapy given postnatally for chronic lung disease.  相似文献   
49.
Summary The understanding of the genetic controls that lead to the development of asthma is essential to its proper diagnosis and management. As we enter the 21 st century, the goals of genetic research in asthma and allergies will be to: 1) identify genetic factors, 2) define environmental cofactors, 3) characterize how genes and the environment work together to cause disease, 4) develop treatment and prevention measures, including drugs designed for the individual's genetic make-up.  相似文献   
50.
The susceptibility of urinary tract Escherichia coli isolates to cotrimoxazole, sulphonamide, trimethoprim, and ampicillin was monitored over an 11-year period. A trend in increasing resistance to cotrimoxazole and trimethoprim was observed, but there was no comparable alteration in sulphonamide resistance. Ampicillin resistance was high at the beginning of the survey period and continued to rise.  相似文献   
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