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Non-insulin-dependent diabetes mellitus (NIDDM) occurs with a higher frequency in Hispanic as compared with non-Hispanic whites. It also appears that there is a higher prevalence of diabetic nephropathy in the Hispanic population when compared with non-Hispanic whites. In the current study, 144 Hispanics and 671 non-Hispanic white NIDDM subjects were studied to determine the possible association of various risk factors and diabetic complications, including overt albuminuria, with diabetic retinopathy. Stereoscopic retinal fundus photographs were obtained and graded by the University of Wisconsin Fundus Photographic Reading Center. We also sought to determine whether risk factors for retinopathy vary between Hispanics and non-Hispanic whites. In the total group, duration of diabetes, glycosylated hemoglobin, neuropathy, diastolic hypertension, use of insulin, and Hispanic ethnicity correlated with the presence of retinopathy. Controlling for severity and duration of diabetes, Hispanics had a significantly increased risk of retinopathy relative to non-Hispanic whites (OR = 2.13, 95% CI = 1.34, 3.37, P = 0.0013). Duration of diabetes and presence of neuropathy were significantly correlated with the presence of diabetic retinopathy in Hispanics and non-Hispanic whites. The presence of overt albuminuria (>200 microg/min), although not related to diabetic retinopathy in non-Hispanic whites, conferred a high risk for diabetic retinopathy in Hispanics (OR = 11.14, CI = 1.20, 103.39, P = 0.0339) independent of other risk factors. In summary, Hispanics with NIDDM have an increased prevalence of diabetic retinopathy when compared with non-Hispanic whites. In addition, overt albuminuria in the Hispanic subjects appears to be a powerful predictor of the diabetic retinopathy.  相似文献   
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The authors studied the impact of edge enhancement and gray scale polarity reversal on the detection of subtle lung cancers. Three experienced readers reviewed 46 biopsy-proved subtle lung cancers and 46 normal controls on chest radiographs that had been digitized into a 1,024 X 1,536-pixel matrix 8 bits deep. Receiver-operating characteristics (ROC) analysis of 1,656 pooled observations indicated that performance was best with the unmodified images (ROC area = 0.83), degraded by moderate enhancement of medium frequencies (ROC area = 0.80), and markedly impaired by severe enhancement of low frequencies (ROC area = 0.69). Gray scale polarity reversal further degraded performance (unenhanced ROC area = 0.74; moderately enhanced ROC area = 0.76; severely enhanced ROC area = 0.76). The authors conclude that edge enhancement and gray scale polarity reversal can impair the detectability of subtle lung cancers on digitized radiographs of medium resolution.  相似文献   
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Rotation of the distal fracture fragment in the supracondylar fracture is a contributing factor in the development of the cubitus varus deformity. Computed tomography (CT) is superior to conventional radiography in the assessment of the position of fracture fragments and was used to study 20 patients with supracondylar fractures after reduction. These fractures were followed up with radiography until healed. As determined from CT scans, rotation of the distal fracture fragment of greater than 10 degrees resulted in an abnormal Baumann angle and a cubitus varus deformity in all patients. Use of CT should facilitate the identification of this complication and thus treatment of these fractures and prevention of subsequent deformity.  相似文献   
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放线瑞香宁碱的解热镇痛作用   总被引:1,自引:0,他引:1  
洪庚辛  滕忠  覃文才  韦宝伟 《药学学报》1988,23(10):779-782
从青藤科植物黑吹风(Illigera sp)总生物碱中分离出一个单体,经化学鉴定命名为放线瑞香宁碱(actinodapbnine简称Ac)。分子式C_(18)H_(17)NO_4,为10-甲氧基-1,2-(次甲二氧基)-6-去甲阿朴菲-9-醇(图1)。动物实验表明,Ac具有解痉、镇痛、局麻及降低小鼠体温等作用,并证明其镇痛作用系非中枢性。本文进一步研究其镇痛作用和对不同动物正常  相似文献   
37.
Peptide YY (PYY) release into the ileal lumen is stimulated by cholecystokinin (CCK) and glucose ingestion. Previous data have implicated vagal activity in the mediation of PYY release into both the systemic circulation and the ileal lumen. The present study was designed to evaluate extrinsic neural involvement in CCK and glucose-stimulated circulating and ileal intraluminal PYY release. Distal ileal Thiry-Vella loops (TVL) of 25 cm were created in seven mongrel dogs. On separate days fasted dogs were given continuous infusions of CCK at 500 ng/kg/hr during the first hour of the study or an oral glucose (1.5 g/kg) tolerance test (OGTT) was performed. Peripheral blood samples and ileal effusates were collected before tests and following either CCK or glucose stimulation for 120 min at 20-min intervals. Ileal PYY recoveries were measured by the instillation and collection of 20 cc of normal saline from the TVL for each 20-min period. The dogs were again tested after surgical denervation of the TVL. OGTT resulted in a significant rise of PYY recovery from the TVL (P less than 0.05), while not affecting circulating PYY. Intravenous CCK resulted in significant increases in both plasma and ileal PYY concentrations (P less than 0.05). Denervation of the TVL decreased PYY recovery from the TVL after both CCK and OGTT, whereas this procedure did not affect circulating PYY levels or basal luminal levels. These data demonstrate the inhibition of CCK- and glucose-stimulated ileal PYY recovery from denervated ileal loops. The extrinsic neural pathways are involved in the mediation of glucose- and CCK-stimulated mechanisms for ileal PYY release.  相似文献   
38.
Aim To determine the clinical benefit response (CBR), time to tumor progression (TTP), overall survival, and effect on quality of life (QOL) of gemcitabine and capecitabine in patients with advanced biliary cancer. Methods Gemcitabine (1000 mg/m2 IV over 30 minutes on days 1 and 8) and capecitabine (650 mg/m2 orally twice daily for 14 days) were administered and repeated every 21 days. All patients completed the European Organization for Research and Treatment of Cancer Core Quality of Life Questionnaire and Pancreatic Cancer Module (EORTC QLQ-C30-PAN 26) questionnaire on day 1 of each cycle. Cumulative QOL scores were calculated. The two-stage design required 17 patients to evaluate the confirmed response at nine weeks. Results Twelve patients with a median age of 54 years were enrolled. A median of eight cycles per patient were completed. With a median follow-up of 18.2 months, the CBR (two partial response and five stable disease) was 58% [95% confidence interval (CI) 28–85%]. Four out of seven patients with CBR had no decline in QOL with chemotherapy. The probability of survival at one year was 0.58. Median TTP and overall survival were 9.0 and 14.0 months, respectively. Nine patients had grade 3 or 4 toxicities. There were no treatment-related deaths. Conclusions Gemcitabine and capecitabine at this dose and schedule are well tolerated and effective and may offer clinical benefit and maintain QOL in patients with advanced biliary cancer. This regimen merits further investigation in the neoadjuvant setting.  相似文献   
39.
Rectal cancer: the sphincter-sparing approach   总被引:8,自引:0,他引:8  
There is considerable skepticism regarding sphincter-preserving surgery for rectal cancer, and 40% to 60% APR rates are reported in many prospective studies. Despite radical surgery, 20% positive margin rates are frequently reported. Rectal carcinoma responds to preoperative chemoradiation therapy with a 10% to 15% pathologic complete response rate. Preoperative therapy offers an opportunity to reduce the positive margin rate and to reduce the APR rate. Because there is significant tumor regression with preoperative therapy, distal margins of less 1 cm are acceptable and do not result in suture line recurrence. APR rate of less than 10% is feasible and better chemotherapy with radiation therapy will reduce the APR to less than 5%.  相似文献   
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