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131.
BM Achauer 《Canadian Metallurgical Quarterly》1997,99(5):1442-1450
A wide variety of lasers provides the plastic surgeon with treatment options that were not available previously. Appropriate, safe use of lasers complements the many therapeutic treatment options available to plastic surgeons. Lasers have introduced a new therapeutic modality. Because of the ways the skin and its defects may be altered with lasers, they will be an increasingly important part of plastic surgery. 相似文献
132.
M Nguyen CL Corless BM Kr?ling C Tran T Atha J Bischoff SH Barsky 《Canadian Metallurgical Quarterly》1997,150(4):1307-1314
Angiogenesis plays an important role in breast cancer growth and metastasis. Multiple adhesion molecules have been shown to perform critical functions in the process of angiogenesis. In this study, we analyzed 15 benign and 22 malignant estrogen-receptor-negative and estrogen-receptor-positive breast specimens for the presence of the endothelial cell adhesion molecules E-selectin and P-selectin. We found that E-selectin's expression was increased in the malignant breast tumors compared with their benign counterparts (23.86% of blood vessels versus 2.47%; P = 0.0005). Furthermore, E-selectin staining was found to be significantly increased in the estrogen-receptor-negative carcinomas compared with the estrogen-receptor-positive ones (P = 0.005). In vitro findings strongly correlated with the in vivo findings and showed a higher degree of E-selectin induction in endothelial cells exposed to conditioned media from estrogen-receptor-negative breast cancer cell lines than from estrogen-receptor-positive ones. The degree of E-selectin induction correlated with the amount of interleukin-1 alpha in the tumor-conditioned media. Neutralizing antibodies to interleukin-1 alpha significantly inhibited the E-selectin expression in endothelial cells exposed to tumor-conditioned media. The results indicate that the endothelial E-selectin expression during angiogenesis is related to breast carcinoma progression in vivo and that this component of angiogenesis may be due directly to tumor-cell-secreted interleukin-1 alpha. 相似文献
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OBJECTIVE: To evaluate the histopathologic changes that occur in human small intestine or time when preserved in Viaspan organ preservation solution. DESIGN: Short segments of human small intestine were placed in standard organ preservation solution (Viaspan) and stored in conditions that mimic the clinical situation associated with clinical organ procurement, preservation, and transplantation. The intestinal segments were removed at sequential time points and placed in 10% formalin. Specimens underwent histopathologic examination to determine time-related changes. SPECIMENS: Short intestinal segments were obtained from seven multiorgan cadaver donors. Specimens were obtained in a way that exactly mimicked small intestinal organ retrieval. RESULTS: Small intestinal histology remained normal for the first 6 hours. After 6 hours, vacuolar separation began to occur between the epithelium and the basement membrane in the upper half of the villi. After 9 hours of cold preservation, epithelial detachment extended deep into the crypts with occasional shedding of cells and villi. CONCLUSIONS: Currently used small intestinal preservation using Viaspan results in considerable histopathologic changes in human jejunum after 9 hours of cold storage. The histopathologic pattern appears normal for the first 6 hours and suggests that preservation times should be limited to this time period when possible. 相似文献
135.
Circulating anticoagulants are a major risk factor for thrombotic problems (eg, myocardial infarction, stroke) and pregnancy complications. The authors present a retrospective survey of anticardiolipin antibody and lupus anticoagulant in 200 consecutive patients presenting to their office. 相似文献
136.
The purpose of this study was to determine the satisfaction and fringe benefits of Texas dental hygienists and compare the data to a recent national study. A blind survey was forwarded to 5,294 active, licensed dental hygienists to obtain data for Texas. Responses were received from 2,172 dental hygienists, a 41 percent response rate. The greatest number of responses came from the larger cities in Texas: Dallas, Houston, Austin, and San Antonio. Fifty-eight percent of Texas hygienists receive paid vacation, 25 percent medical insurance, 37 percent sick pay, and 26 percent receive some type of retirement. Nationally, the figures are higher. The survey also sought to determine satisfaction levels. Most dental hygienists are satisfied with their salary (65%), their career (85%), and feel secure in their employment (92%), while only 46 percent are satisfied with benefits. The survey results are inconclusive for hygienists' in the state of Texas based on the 41 percent response rate. Practical information may assist employers in recruitment and retention of a dental hygienist into the practice. 相似文献
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BM Sanner C Doberauer M Konermann A Sturm W Zidek 《Canadian Metallurgical Quarterly》1997,157(21):2483-2487
BACKGROUND: Obstructive sleep apnea syndrome (OSAS) is associated with an increased cardiovascular morbidity, including pulmonary hypertension. Little is known about factors influencing the degree of pulmonary hypertension and left ventricular dysfunction in patients with OSAS, especially in the absence of concomitant lung disease. METHODS: Right heart catheterization, arterial blood gas analysis, and pulmonary function tests were performed in 92 consecutive patients (81 men and 11 women; mean +/- SD age, 53.1 +/- 11.0 years) with polysomnographically verified OSAS, in whom clinically significant lung disease was excluded. RESULTS: Eighteen patients (20%) had mild pulmonary hypertension; 8 (44%) of them also had increased pulmonary capillary wedge pressures (Ppew). Left ventricular dysfunction was associated with arterial hypertension. Only Ppcw (r = 0.51; P < .001) and the percentage of time during sleep spent with an oxygen saturation below 90% (as an indicator of the severity of OSAS) (r = 0.34; P = .003) were significantly and independently associated with pulmonary artery pressure. CONCLUSIONS: Obstructive sleep apnea syndrome can cause mild pulmonary hypertension, even in the absence of pulmonary disease. In these patients, pulmonary hypertension is of the postcapillary type, or-in patients with normal left ventricular function-strongly related to the severity of OSAS. Our findings indicate that OSAS may constitute an important, and independent, risk factor for pulmonary hypertension. 相似文献