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231.
四种可溶性载体对骨形态发生蛋白在小鼠体内诱导成骨活性的影响 总被引:28,自引:0,他引:28
以四种可溶性物质作为牛骨形态发生蛋白(bBMP)的载体,通过实验观察哪种物质是bBMP的有效缓释载体。将聚乙烯吡咯烷酮(PVP)、葡聚糖、羟乙基淀粉(HES)、甘露醇分别与等量bBMP复合后,注射入小鼠股部肌肉,观察组织学成骨及测定标本内钙含量。结果,bBMP/PVP有良好成骨,吸收较快,未见炎症及排斥反应,其混悬液较稳定,具有良好的适针性及可注射性,bBMP/甘露醇只有很低成骨率。其余各组未见成骨。PVP对bBMP具有满意助溶、助悬及缓释载体作用,对bBMP活性无损害,生物相容性好。 相似文献
232.
A. Reinert A. Kaske S. Mense 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1998,121(2):174-180
The density of substance P (SP)-, calcitonin gene-related peptide (CGRP)- and vasoactive intestinal polypeptide (VIP)-immunoreactive
(ir) nerve endings was quantitatively evaluated in intact and inflamed gastrocnemius-soleus muscle of the rat. In persistently
inflamed muscle (12 days after a single injection of Freund’s adjuvant into the muscle), the density of SP-ir fibres was significantly
increased. CGRP- and VIP-ir fibres displayed an insignificant increase in density. The density of fibres ir for nerve growth
factor (NGF) and for growth-associated protein 43 (GAP-43/B-50), a marker for axonal sprouting, regeneration and synaptic
reorganisation, increased significantly in persistently inflamed muscle. The data are consistent with the established contribution
of NGF on the expression of SP and GAP-43 in afferent neurones under the influence of a persistent inflammation.
Received: 8 September 1997 / Accepted: 12 February 1998 相似文献
233.
GP SCHWAB AL BLUM E BODNER B DALLEMAGNE K GLASER H KOOP F PACE W RÖSCH JR SIEWERT G WETSCHER 《Journal of gastroenterology and hepatology》1997,12(12):785-789
Gastroesophageal reflux disease (GERD) is the most common disease of the upper gastrointestinal tract. With the introduction of proton pump inhibitors medical treatment of GERD has been significantly improved. However, the development of laparoscopic antireflux surgery resulted in an increasing interest of surgeons in this disease. An interactive meeting was organized in order to develop an agreement between gastoenterologists and surgeons regarding therapeutic decisions and this is the main topic of this paper. 相似文献
234.
235.
236.
新生儿脑病S-100蛋白监测与预后的研究进展 总被引:1,自引:0,他引:1
目的:通过监测新生儿缺氧缺血性脑病(HIE)患儿血清中S-100蛋白含量的动态变化,建立对HIE患儿的早期科学诊断及预后评估技术指标。并探讨S-100蛋白浓度变化与病情的严重程度及转归之间的关系。方法:采用酶联免疫吸附试验、双抗体夹心法检测,对120例HIE有症状组患儿(HIE轻度症状组40例,HIE中度症状组40例,HIE重度症状组40例)和40例新生儿窒息组患儿与40例对照组健康新生儿血清S-100蛋白含量进行检测,并进行动态观察。结果:①HIE有症状组不同时期血清S-100蛋白含量均显著高于对照组(P<0.01);②新生儿窒息组不同时期的血清S-100蛋白含量也明显高于对照组(P<0.01);③HIE有症状组血清S-100蛋白含量明显高于新生儿窒息组(P<0.05)。结论:HIE有症状组患儿病情越重,其血清S-100蛋白含量则越高,提示血清S-100蛋白可作为判断HIE病情程度的客观依据和早期诊断以及预后评估HIE的主要指标。 相似文献
237.
硬膜外腔阻滞对胸部手术应激反应的影响 总被引:33,自引:1,他引:32
目的 观察硬膜外腔阻滞对胸部手术应激激素和细胞因子的影响。方法20例食管癌手术病人,随机分为两组,每组10例,即全麻复令硬膜外腔阻滞(GEA)组和全麻(GA)组,分别测定麻醉诱导前、手术2h、手术4h、术毕、术后1d及术后3d的血浆去甲肾上腺素、肾上腺素、血清促肾上腺皮质激素(ACTH)、皮质醇、C-反应蛋白、IL-6及IL-10的水平。结果 血浆去甲肾上腺素和血清皮质醇GEA组术中术后无显著改变,但GA组术毕和术后1d显著升高(P<0.05),术后3d恢复至术前水平,组间比较前者有显著差异(P<0.05)。两组血浆肾上腺素、IL-10术中术后均无显著变化。两组血清ACTH、IL-6及CRP术中术后均显著升高(P<0.05),组间比较无显著差异。结论 硬膜外腔阻滞可以减轻胸部手术的应激反应。IL-6是较CRP更灵敏的反映组织损伤的炎性指标。 相似文献
238.
Alexandra H. Heussner Evelyn O'Brien Daniel R. Dietrich 《Experimental and toxicologic pathology》2002,54(2):151-159
The mycotoxin ochratoxin A (OTA) is a potent renal carcinogen in rodents and induces renal fibrosis in pigs. Furthermore, OTA has been associated with the development of renal tumors and nephropathies in humans. Large species- and sex-differences are observed in sensitivity toward OTA-mediated toxicity and carcinogenicity, yet neither the mechanism(s) resulting in OTA toxicity nor the reasons for the observed species- and sex-specificities are known. This paper investigated variations in OTA handling viz binding to renal proteins which could possibly explain the observed differences in OTA susceptibility in vivo and in vitro. The results obtained via a modification of a standard receptor-binding assay demonstrated the presence of at least one homogeneous binding component in renal cortical homogenates from pig, mouse, rat and humans. This component was shown to bind OTA in a specific and saturable manner. A range of compounds selected for their affinity for steroid receptors and/or for various known organic anion transporters were employed in a competition assay to answer the question whether this homogenous OTA binding component represents a steroid-like receptor component or one of the known organic anion transporters of the kidney. Although many of the compounds were able to compete with OTA for protein-binding, the competition patterns displayed a distinct species specificity and did not correspond to the competition patterns associated with presently known organic anion transporters of the kidney in the mouse, rat or human. The data thus suggests the presence of a new organic anion transporter or more likely, a cytosolic binding component of unknown function with high affinity and capacity for OTA binding in humans, rats, mice and possibly pigs. 相似文献
239.
High-protein Weight-loss Diets: Are They Safe and Do They Work? A Review of the Experimental and Epidemiologic Data 总被引:6,自引:0,他引:6
Julie Eisenstein M.D. Susan B. Roberts Ph.D. Gerard Dallal Ph.D. Edward Saltzman M.D. 《Nutrition reviews》2002,60(7):189-200
Recommendations for increased consumption of protein are among the most common approaches of popular or fad diets. This review summarizes the effects of dietary protein on satiety, energy intake, thermogenesis, and weight loss, as well as its effect on a variety of health outcomes in adults. In short-term studies, dietary protein modulates energy intake via the sensation of satiety and increases total energy expenditure by increasing the thermic effect of feeding. Whereas these effects did not contribute to weight and fat loss in those studies in which energy intake was fixed, one ad libitum study does suggest that a high-protein diet results in a greater decrease in energy intake, and therefore greater weight and fat loss. In terms of safety, there is little long-term information on the health effects of high-protein diets. From the available data, however, it is evident that the consumption of protein greater than two to three times the U.S. Recommended Daily Allowance contributes to urinary calcium loss and may, in the long term, predispose to bone loss. Caution with these diets is recommended in those individuals who may be predisposed to nephrolithiasis or kidney disease, and particularly in those with diabetes mellitus. 相似文献
240.
Gü l Gü rsel Haluk Tü rktas Nahide G k ora Ishak
zel Tekin 《The Journal of asthma》1997,34(4):313-319
The aim of the present study was to investigate whether sputum eosinophil cationic protein (ECP) concentrations could be a useful marker in the differential diagnosis between intrinsic asthma and chronic obstructive pulmonary disease (COPD). For this purpose total blood eosinophil counts were obtained and concentrations of serum and sputum ECP from 10 nonatopic asthmatics with a mild attack and 9 COPD patients with acute exacerbation were measured by radioimmunoassay. Mean serum ECP concentration was 54.3 ± 23.0 g/L in the asthmatic group and 83.3 ± 79.2 g/L in the COPD group (p: n.s.). In the group of asthmatics mean sputum ECP level was 984.5 ± 1245.5 mg/L/g sputum and in the COPD group it was 417.5 ± 363.5 mg/L/g sputum. There was no significant difference in sputum ECP levels between patients with asthma and COPD. We conclude that neither sputum nor serum ECP levels are useful markers in differential diagnosis of asthma attack and acute exacerbation of COPD. 相似文献