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151.
F X Pi-Sunyer 《Nutrition (Burbank, Los Angeles County, Calif.)》1991,7(4):292-294
There are several possible determinants of obesity, including impaired thermogenesis and the differential utilization of fuels in different tissues. Whereas hypometabolism may initiate obesity in some people, once obese, individuals tend to manifest a higher resting metabolic rate because of their greater fat-free mass, exhibit an impaired thermic response to food, and expend more calories than lean individuals for equivalent amounts of activity. As a result, over a 24-h period, obese people generally expend more energy than lean people. A second determinant of obesity is related to fuel utilization and suggests that those predisposed to be obese may have an innate insulin resistance in muscle, leading to decreased uptake, oxidation, and storage of glucose in this tissue. As a result, the glucose is shunted to adipose tissue, where it is stored. With regard to treatment of obesity, emphasis on increased energy expenditure through the inclusion of reasonable amounts of activity is essential. However, this must always be combined with restraint in caloric intake. 相似文献
152.
153.
亚急性甲状腺炎的CT诊断 总被引:4,自引:1,他引:3
目的:探讨亚急性甲状腺炎的CT表现和特点,提高对该病影像表现的认识。材料和方法:回顾性分析10例亚急性甲状腺炎CT影像特征及临床资料,共16个病灶,其中9例经手术病理证实,1例临床证实。同时抽取局限型甲状腺癌65例,就部分征象作对照分析。结果:亚急性甲状腺炎局限性3例,弥漫性7例。CT表现分3型:①局限于甲状腺一侧叶的低密度病变,病变甲状腺肿大,峡部可受累,3例;②甲状腺两叶各有一低密度病变,呈不对称肿大,病灶之间有正常甲状腺组织,6例共12个病灶;③甲状腺两叶及岬部均匀肿大,略不对称,1例。CT平扫病变为低密度,增强扫描后呈轻到中度均匀强化(15/16),腺内更低密度结节少见(1/16)。病变处甲状腺边缘模糊(16/16),与正常甲状腺组织界限不清(15/16),而局限型甲状腺癌病灶与正常甲状腺腺组织分界清楚(62/65),两者极不一样(P<0.01)。结论:亚急性甲状腺炎CT表现有一定特点,熟悉这些特点对于诊断及鉴别诊断很有帮助。 相似文献
154.
单一小切口带锁钉固定治疗"浮膝"损伤 总被引:3,自引:0,他引:3
[目的]探讨应用单一小切口治疗“浮膝”损伤的手术方法及手术适应证。[方法]对12例“浮膝”损伤病人采取C型臂X线机透视下闭合复位,膝关节屈曲30°~40°于髌韧带内侧缘做3~5 cm的切口,经股骨髁间窝逆行穿入股骨带锁钉;膝关节屈曲90°经同一切口向胫骨打入带锁钉。[结果]经过1~3年的随访,本组病人均骨性愈合,1例膝关节功能仅屈曲到90°,其它膝关节功能恢复到伤前水平。[结论]该术式创伤小,操作简单,固定牢固,能早期进行膝关节功能锻炼,早期对膝关节功能无影响,有无远期影响有待长期随访。 相似文献
155.
O Jegaden X Martin F Canton A Gelet J M Dubernard 《Journal des maladies vasculaires》1987,12(4):315-318
Sixteen patients underwent surgical treatment for severe renovascular hypertension with rapidly progressive renal failure. These patients were assessed preoperatively with the measurement of serum creatinine and blood-urea levels (means 271 +/- 204 mumol/l and 15.6 +/- 10.3 mmol/l respectively), and renal clearances. 5 patients underwent aorto-renal bypass (bilateral in one case) and 11 patients were treated by autotransplantation of the kidney. Operative mortality was 6.2%. Early results were assessed at 1 and 6 months postoperatively. Renal function was normal in 8 patients, improved in 5 (p less than 0.05), unchanged in 1 and worse in 1 by aorto-renal bypass thrombosis. At long-term with a minimum follow-up of 12 months (mean 31 +/- 12 months), the initial improvement in renal function remained steady in 12 patients whilst 1 patient has gone on to hemodialysis. At middle and long-term, 81% of the patients were normotensive without medication or had improved blood pressure (p less than 0.001). These good results confirm the reversibility of renal ischemic lesions and support an aggressive attitude towards the use of revascularization in the surgical treatment of such patients with renovascular hypertension and renal failure. 相似文献
156.
The cardiotoxic effects of hydralazine and prenalterol, given alone and in combination, were assessed in rats and rabbits. Acute myocardial necrosis was induced by a single administration of each drug alone in rats. However, the incidence and severity of lesions were markedly enhanced when both drugs were given in combination. Rats that received the same treatment for 10 consecutive days showed minimal or no acute necrosis, demonstrating the development of a resistance to further cardiotoxic effects of the drugs. Rabbits showed only minimal lesions when either drug was used alone and no enhancement of lesions when they were given in combination. From these data, it is concluded that the possibility of a cardiotoxic interaction exists when these drugs are used in combination and that the heavy rat (500-600 g) is a more sensitive model than the rabbit for studies of this nature. 相似文献
157.
158.
An indirect enzyme-linked immunosorbent assay (ELISA) for the detection of hexoestrol (HES) was developed, optimized and validated for the analysis of HES in pork. Many parameters, such as the volume ratio of solution A and solution B, colour developing time, pH value, incubation time, the volume ratio of the standard solution and diluted antiserum, blocking solution, blocking condition, coating solution and coating condition were studied and optimized in the paper. The regression equation of the final inhibition curve is y = - 0.3345x + 1.4955, R2=0.9913. The linear range is 0.1-8.1 ng/ml, and the IC50 is 0.671 ng/ml. The specificity of the assay was evaluated by the cross-reactivity rates of six compounds, of which two structurally related compounds had a relatively higher cross-reactivity rate of 25% and 6%. HES was added into a pork sample at 5 ng/g level and then the sample was extracted. The recovery is between 49.6% and 79.2%, and the variation coefficient is 0.164. 相似文献
159.
160.
股前外侧区穿支动脉的形态学研究及皮瓣设计 总被引:4,自引:2,他引:2
目的探讨以旋股外侧动脉降支为蒂的皮瓣设计方法,以便增加术前多普勒定位的准确性。方法6具动脉灌注明胶-氧化铅混悬液的新鲜成人整尸标本,解剖观测股前外侧区穿支,通过血管造影术和拍摄X线片测量其直径、行程、分支和定位。用3D—doctor和Scion Image软件分别测量穿支供血的趋向性、三维重建和单穿支供血面积。结果股前外侧区共有外径大于0.5mm穿支16支,平均外径0.8mm,平均供血面积45.61cm^2,其中20%为肌间隙穿支,80%为肌皮穿支。平均蒂长为(3.15±1.43)cm。自旋股外侧动脉降支发出的穿支在浅筋膜中的平均长度为2.63cm。结论改良的氧化铅-明胶灌注技术可以为皮动脉和穿支皮瓣的研究提供高质量的血管造影图像。本研究发现股前外侧单穿支皮瓣的最大供血面积是30cm×20cm。以股前外侧区穿支设计的穿支皮瓣可以移植到下肢或身体其他部位。 相似文献