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排序方式: 共有911条查询结果,搜索用时 15 毫秒
71.
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G L Moneta R A Yeager R Dalman R Antonovic L D Hall J M Porter 《Journal of vascular surgery》1991,14(4):511-8; discussion 518-20
Mesenteric artery duplex scanning appears promising for detection of splanchnic artery stenosis or occlusion or both in patients with symptoms suggestive of chronic intestinal ischemia. However, no specific duplex criteria have been developed for detection of mesenteric artery stenosis. We obtained mesenteric artery duplex scans and infradiaphragmatic lateral aortograms in 34 patients to determine duplex criteria for mesenteric stenosis. Seventy percent or greater angiographic stenosis was present in 10 superior mesenteric arteries and 16 celiac arteries. Duplex scans were reviewed to determine if celiac artery and superior mesenteric artery ratios of peak systolic velocities and end-diastolic velocities to peak aortic systolic velocity, as well as celiac artery and superior mesenteric artery peak systolic velocities and end-diastolic velocities alone, could predict a greater than or equal to 70% angiographic stenosis or occlusion or both. The results obtained by use of receiver operator curves indicated peak systolic velocity alone was an accurate predictor of splanchnic artery stenosis. Specifically, a peak systolic velocity greater than or equal to 275 cm/sec in the superior mesenteric artery and greater than or equal to 200 cm/sec in the celiac artery or no flow signal (superior mesenteric artery and celiac artery) predicted a 70% to 100% stenosis with sensitivity, specificity, and positive predictive values of 89%, 92%, and 80% for the superior mesenteric artery. Similar values for the celiac artery were 75%, 89%, and 85%, respectively. End-diastolic velocities or calculated velocity ratios conveyed no additional accuracy in predicting splanchnic artery stenosis. 相似文献
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Dermatoses in 156 obese adults. 总被引:1,自引:0,他引:1
L García-Hidalgo R Orozco-Topete J Gonzalez-Barranco A R Villa J J Dalman G Ortiz-Pedroza 《Obesity research》1999,7(3):299-302
BACKGROUND: Skin diseases are mentioned as a frequent finding in the obese patient. However, to our knowledge no study has been done on this subject. OBJECTIVE: To determine the prevalence of skin diseases associated with different obesity grades and if any dermatosis can be considered an obesity marker. MATERIALS AND METHODS: A cross-sectional study of 156 obese patients who were 110% to 293% overweight were included. Complete medical history and dermatological examination were done. RESULTS: In the 126 female and 30 male obese patients, grades I to V, with a body mass index (BMI) of 27-51, cutaneous findings with statistical significance for linear trend were: plantar hyperkeratosis 54 patients p = 0.00001; acanthosis nigricans 46 patients p = 0.00005; striae 67 patients p = 0.03; skin tags 69 patients p = 0.01; keratosis pilaris 33 patients p = 0.007. Patients with plantar hyperkeratosis were distributed in the obesity groups as follows: grade I = 3 patients; grade II = 7 patients; grade III = 8 patients; grade IV = 17 patients; and grade V = 19 patients. Of the 76 diabetic patients, 26 had acanthosis nigricans, 38 had skin tags, and 27 had plantar hyperkeratosis. DISCUSSION: Plantar hyperkeratosis should be considered as a cutaneous stigma of severe obesity. This is probably a result of pressure directly related to the excess weight. 相似文献
76.
Dunnick NR; Svetkey LP; Cohan RH; Newman GE; Braun SD; Himmelstein SI; Bollinger RR; McCann RL; Wilkinson RH Jr; Klotman PE 《Radiology》1989,171(1):219-222
Intravenous digital subtraction renal angiography (DSRA) has been compared with conventional angiography only in small, selected series of hypertensive patients. The authors prospectively examined with intravenous DSRA 94 patients at increased risk for renovascular hypertension and compared these studies with conventional angiography. A stenosis of at least one main renal artery was identified with intravenous DSRA in 22 patients and confirmed in 20 patients. No significant stenoses were seen with conventional angiography in any of the 64 patients in whom lesions were not seen with intravenous DSRA. Since inadequate DSRA studies were considered positive for renal artery stenosis, the sensitivity of intravenous DSRA was 100% (25 of 25); specificity, 93% (64 of 69); positive predictive value, 83% (25 of 30); and negative predictive value, 100% (64 of 64). The authors conclude that intravenous DSRA is a sensitive test for identifying stenosis of the main renal arteries and is appropriate to use as a screening test among patients at increased risk for renovascular hypertension. 相似文献
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Focal Adhesion Kinase Is Important for Fluid Shear Stress‐Induced Mechanotransduction in Osteoblasts
Suzanne RL Young Rita Gerard‐O'Riley Jae‐Beom Kim Fredrick M Pavalko 《Journal of bone and mineral research》2009,24(3):411-424
Mechanical loading of bone is important for maintenance of bone mass and structural stability of the skeleton. When bone is mechanically loaded, movement of fluid within the spaces surrounding bone cells generates fluid shear stress (FSS) that stimulates osteoblasts, resulting in enhanced anabolic activity. The mechanisms by which osteoblasts convert the external stimulation of FSS into biochemical changes, a process known as mechanotransduction, remain poorly understood. Focal adhesions are prime candidates for transducing external stimuli. Focal adhesion kinase (FAK), a nonreceptor tyrosine kinase found in focal adhesions, may play a key role in mechanotransduction, although its function has not been directly examined in osteoblasts. We examined the role of FAK in osteoblast mechanotransduction using short interfering RNA (siRNA), overexpression of a dominant negative FAK, and FAK?/? osteoblasts to disrupt FAK function in calvarial osteoblasts. Osteoblasts were subjected to varying periods oscillatory fluid flow (OFF) from 5 min to 4 h, and several physiologically important readouts of mechanotransduction were analyzed including: extracellular signal‐related kinase 1/2 phosphorylation, upregulation of c‐fos, cyclooxygenase‐2, and osteopontin, and release of prostaglandin E2. Osteoblasts with disrupted FAK signaling exhibited severely impaired mechanical responses in all endpoints examined. These data indicate the importance of FAK for both short and long periods of FSS‐induced mechanotransduction in osteoblasts. 相似文献
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80.
Blood donation leads to a decrease in natural killer cell activity: a study in normal blood donors and cancer patients 总被引:2,自引:0,他引:2
Transfusion-induced immunosuppression has long been known to be beneficial for organ transplantation patients, but recent retrospective studies suggest that blood transfusions may be detrimental for patients with cancer. If autologous blood is used to avoid immunosuppression, the assumption is that the procedure, involving blood donation, is immunologically neutral. In the present study, this assumption was evaluated by monitoring 33 normal blood donors and 16 colorectal cancer patients before and after donation of 1 (500 mL) and 2 units of blood, respectively. The cancer patients belonged to the autologous arm of a randomized trial in which the effects of allogeneic versus autologous blood on cancer prognosis were studied. The patients donated 2 units of blood with an interval of 3 to 4 days between donations. Flow cytometric analysis revealed that blood donation by normal donors and cancer patients had no effect on the proportion of B, T, and natural killer (NK) cells. Only the total number of lymphocytes was significantly decreased in the normal donors on Day 12 after donation. Blood donation had no significant effect on T-cell function assessed by phytohemagglutinin stimulation in normal donors or in cancer patients donating 2 units of blood. A significant depression of NK cell function (88% and 74% of predonation levels) was observed in normal donors on Days 2 and 5 after donation; on Day 12, the activity was again normal. Colorectal cancer patients had a significantly depressed NK cell activity (54% of predonation activity) on Day 12 after the first donation.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献