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排序方式: 共有565条查询结果,搜索用时 31 毫秒
51.
BACKGROUND: Few data exist about visits to primary care clinicians for breast symptoms in the United States. OBJECTIVE: To determine how often women present with breast symptoms, how these symptoms are evaluated, and how often cancer is diagnosed. DESIGN: Retrospective cohort study. SETTING: Staff-model division of a large health maintenance organization (HMO) in New England. PATIENTS: 2400 women who were 40 to 69 years of age as of 1 July 1983 and were continuously enrolled in the HMO until 30 June 1995. MEASUREMENTS: Information on all breast-related encounters from 1 July 1983 to 30 June 1993 was abstracted. Type of symptom, clinicians' findings and recommendations, and all subsequent evaluations were recorded. Cases of cancer diagnosed subsequent to the symptom were determined. RESULTS: Sixteen percent of the HMO population presented with a breast symptom during the 10-year period, for a rate of 22.8 presentations per 1000 person-years. Women younger than 50 years of age presented nearly twice as often as older women (P = 0.001). Women with breast symptoms had lower rates of screening than other women before presenting but higher rates of screening afterward (P < 0.001). Symptoms were evaluated beyond the initial visit in 66% of patients, and invasive procedures were performed in 27% of patients. Cancer was found in 6.2% of patients and 4.5% of episodes; rates of cancer detection varied significantly by type of symptom but not by patient age. CONCLUSIONS: Breast symptoms among women 40 to 70 years of age were common in this primary care practice. Evaluation beyond initial examinations was frequent, and invasive procedures were performed for 27% of patients. Cancer was diagnosed in more than 4% of episodes, indicating that follow-up of breast symptoms is important in primary care practices. 相似文献
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53.
M Toraason J S Bohrman E Elmore G Wyatt D McGregor S E Willington W Zajac 《Journal of toxicology and environmental health》1991,34(1):95-102
Asphalt fume condensate is a skin carcinogen in mice, yet this complex mixture contains relatively low levels of known carcinogenic initiators. Consequently, its biological activity has been attributed to the presence of cocarcinogenic or tumor-promoting agents. One of several proposed mechanisms of tumor promotion is inhibition of intercellular communication. In an attempt to determine if asphalt fume has tumor-promoting potential inhibition of intercellular communication was measured in V79 cells exposed to fractionated asphalt fume condensate. Fume from air-blown Arabian crude asphalt was trapped and separated into five fractions by preparative-scale high-pressure liquid chromatography. The parent fume condensate and the five fractions inhibited intercellular communication in a concentration-dependent fashion, with a minimum effective concentration of 2.5 microgram/ml for the most potent fraction. Cytotoxicity assays were performed at the same time and concentrations as the metabolic cooperation assays. Cytotoxic responses paralleled the inhibition of intercellular communication. 相似文献
54.
55.
J. Richard Heys Charles S. Elmore 《Journal of labelled compounds & radiopharmaceuticals》2009,52(6):189-200
Reports in the literature appear to differ on the effects of some C3 substituents on the relative efficiencies of isotope exchange in the nonidentical C2‐ and C6‐positions catalyzed by organoiridium complexes. Controlled experiments were conducted using a set of model substrates in attempts to clarify these effects. The results clearly showed that, in common with most previous findings, alkyl substituents at C3 reduced the rate of isotope incorporation into C2 relative to C6, as expected on steric grounds. In contrast, all substituents possessing electron lone pairs resulted in a lessening of the inhibition of C2‐vs‐C6 labeling or promoted C2 labeling to such a degree that it became faster than that at C6. NMR measurements on equimolar mixtures of active iridium complex with selected substrates revealed that the ratios of C2‐ and C6‐iridacycles present in solution correlated with the relative rates of ortho‐deuteration in the rate studies. The results of the two studies, taken together, suggest that conventional explanations for the origin of the positive meta‐effect may not be adequate for the present system. An alternative hypothesis is advanced. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
56.
J R Elmore J Eldrup-Jorgensen W H Leschey W E Herbert R C Dillihunt F S Ray 《Archives of surgery (Chicago, Ill. : 1960)》1990,125(6):734-7; discussion 738
Computerized topographic brain mapping processes standard electroencephalographic data and displays it in a color map, thus simplifying interpretation. During a 2-year period, 65 carotid endarterectomies were performed with the use of brain mapping as the sole criterion for shunt replacement. Forty-three patients (66%) were found to have abnormal brain maps preoperatively. Ten patients (15%) developed ischemic changes after cross-clamping (all resolved after shunt placement). Postoperative brain maps were unchanged in 54 patients (83%) and improved in 7 patients (11%). A new, small focal abnormality was identified in 4 patients without shunts (6%), none of whom had a change in neurologic status. The overall major morbidity and mortality was 1.5%. Computerized brain mapping is a sensitive and readily interpretable means of monitoring cerebral perfusion during carotid surgery. We found the computerized electroencephalographic data to be a dependable criterion for selective shunting and for confirmation of shunt patency during carotid endarterectomy. 相似文献
57.
58.
Gustafson PA Zarro DL Palanzo DA Manley NJ Montesano RM Quinn M Elmore BA Castagna JM 《Perfusion》2002,17(2):141-144
Continuous insulin infusion was not an effective mode of treatment in maintaining safe blood glucose levels (<200 mg/dl) during the intraoperative period of diabetic patients requiring open-heart surgery. The two modifications investigated to gain better control of the blood glucose were a change in the base solution of the cardioplegia and the use of a sliding insulin scale. Fifty patients including Type I and Type II diabetics were selected for the purpose of this study. The patients were then randomly divided into two groups categorized by the type of cardioplegic solution administered and the mode of insulin treatment. Group I patients received a dextrose 5%-based cardioplegic solution and blood glucose was treated via continuous intravenous insulin infusion. Group II patients received normal saline 0.9%-based cardioplegic solution and blood glucose was treated via sliding scale. Blood glucose levels were monitored pre- and postcardiopulmonary bypass (CPB) and every 30 min while on CPB. Glucose values were analyzed by group t test. A p value of <0.05 was considered statistically significant. When comparing Group I (mean=258 mg/dl) with Group II (mean=158 mg/dl), there was a statistically significant difference between the glucose values at each of the time intervals when the glucose values were recorded. In conclusion, Group II maintained an acceptable blood glucose level (<200 mg/dl) throughout the entire intraoperative period, which suggests that the combination of the sliding insulin scale and modification of the base cardioplegic solution was an effective mode of treatment. 相似文献
59.
Tony Ro Johanan Hsu Nafi E. Yasar L. Caitlin Elmore Michael S. Beauchamp 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2009,195(1):135-143
Certain sounds, such as fingernails screeching down a chalkboard, have a strong association with somatosensory percepts. In
order to assess the influences of audition on somatosensory perception, three experiments measured how task-irrelevant auditory
stimuli alter detection rates for near-threshold somatosensory stimuli. In Experiment 1, we showed that a simultaneous auditory
stimulus increases sensitivity, but not response biases, to the detection of an electrical cutaneous stimulus delivered to
the hand. Experiment 2 demonstrated that this enhancement of somatosensory perception is spatially specific—only monaural
sounds on the same side increased detection. Experiment 3 revealed that the effects of audition on touch are also frequency
dependent—only sounds with the same frequency as the vibrotactile frequency enhanced tactile detection. These results indicate
that auditory information influences touch perception in highly systematic ways and suggest that similar coding mechanisms
may underlie the processing of information from these different sensory modalities. 相似文献
60.
CONTEXT: Although having a usual source of care has been associated with cancer screening, whether there is additional benefit from continuity with a specific physician is uncertain. In addition, little is known about the relationship between continuity of care and receipt of colorectal and prostate cancer screening. METHODS: Subjects were enrolled in a Washington State health plan that operates an integrated delivery system that emphasizes access to primary care. Among patients age 50-78 years old with 2 or more primary care visits in 2002-2003 (N = 67,633), we determined whether higher continuity (>/=50% of visits with the most visited primary care provider) was associated with colorectal, breast, and prostate cancer screening. Random-effects logistic regression estimated adjusted percentages of patients who received fecal occult blood testing, lower endoscopy (sigmoidoscopy or colonoscopy), screening mammography, and prostate specific antigen (PSA) testing. RESULTS: Patients with higher continuity were more likely to receive fecal occult blood testing than patients with lower continuity (28.9% vs. 26.8%; P < 0.001) but less likely to receive lower endoscopy (12.9% vs. 14.3%; P < 0.001). Although higher continuity was not significantly associated with screening mammography (P = 0.38), men with higher continuity were more likely to receive PSA testing than men with lower continuity (39.4% vs. 37.4%; P = 0.008). CONCLUSIONS: In an insured population with a high degree of primary care access, continuity with a specific primary care physician was associated with the selection of less invasive colorectal cancer screening tests by patients and physicians and greater likelihood of PSA testing. 相似文献