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123.
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
124.
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
125.
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
126.
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
127.
SOLVEIG WÅLLBERG-JONSSON GÖSTA DAHLÉN OWE JOHNSON GUNILLA OLIVECRONA & SOLBRITT RANTAPÄÄ-DAHLQVIST 《Journal of internal medicine》1996,240(6):373-380
Objective. To evaluate the impact of chronic inflammation on lipoprotein lipase (LPL) levels and triglyceride metabolism in patients with rheumatoid arthritis (RA). Design. Plasma levels of LPL activity and mass before and after heparin were determined in post-menopausal women with active RA and in controls. The results were related to lipid levels and inflammatory variables. The LPL activity and mass together with triglyceride levels were also measured before and 6 h after an oral fat load. Setting. The study was performed on in- and out-patients at a University Rheumatology clinic. The controls came from the same reference area. Subjects. Altogether 17 consecutive post-menopausal female patients with RA and 16 age and sex matched controls were enrolled for the initial determination of LPL. Fifteen of the patients and 15 of the controls agreed to take part in the fat load. Of these, one patient and one control were excluded. Main outcome measures. LPL determination: basal levels and post-heparin levels of LPL activity and mass. Correlations between LPL and blood lipids (cholesterol, triglycerides), lipoprotein levels (high density lipoprotein, HDL; low density lipoprotein, LDL), erythrocyte sedimentation rate (ESR) acute phase proteins (orosomucoid, haptoglobin, fibrinogen mass) and cytokines (tumour necrosis factor α, TNF-α; interleukin 1β, IL-1β; and interleukin-6, IL-6). Fat tolerance test: LPL activity, mass and triglyceride levels before and 6 h after a per oral fat load. Results. Pre-heparin LPL mass (P<0.01) and activity (P<0.01) were significantly lower in the rheumatoid patients. Pre-heparin LPL mass showed no correlation to the lipid levels, but an inverse correlation to several inflammatory parameters; it was significant for orosomucoid (rs=?0.63, P<0.05) and C-reactive protein (CRP) (rs=?0.54, P<0.05) and close to significant for haptoglobin (rs=?0.48, P=0.087) and IL-6 (rs=?0.52, P=0.061). Six hours after a lipid load the LPL activity and mass were significantly lower in RA (P<0.05 and P<0.01, respectively) but the triglyceride level was not significantly different compared to controls. Conclusion. An inverse relationship exists between inflammatory status and pre-heparin LPL mass. Pre-heparin LPL mass reflects mainly the inactive monomeric fraction of LPL. This has been shown to hinder the uptake of remnant lipoprotein particles through competition with lipoprotein bound dimeric LPL for the LDL receptor-related protein (LRP receptor) on hepatocytes and macrophages in culture. A decrease of the level of monomeric LPL in plasma may thus be beneficial for remnant catabolism. The same mechanism may on the other hand increase macrophage uptake of lipids. This may not affect global lipid metabolism but may be important in driving the atherosclerotic process in the vessel wall. 相似文献
128.
糖尿病大鼠红细胞膜Band3蛋白的变化 总被引:1,自引:0,他引:1
目的:研究糖尿病时红细胞膜蛋白的变化。方法:注射STX诱发大鼠糖尿病,通过SDS-PAGE对糖尿病3个月大鼠红细胞膜蛋白进行电泳分析。结果:糖尿病大鼠红细胞膜Band3蛋白含量明显低于正常对照大鼠。结论:由于Band3蛋白是红细胞膜蛋白的主要成分,参与红细胞变形、物质通透等多方面的功能活动,其变化可能会直接影响红细胞的结构和功能,因此,糖尿病时Band3蛋白的变化值得进一步深入研究。 相似文献
129.
Objective To investigate the effect of rosiglitazone on p38 mitogen-activated protein kinase (p38MAPK) pathway in polycystic kidney cyst-lining epithelial cells. Methods The cyst-lining epithelial cells (PKD cells) from human polycystic kidney were treated with rosiglitazone (10 μmol/L), peroxisome proliferator-activated receptor-γ (PPARγ) inhibitor GW9662 (10 μmol/L), rosiglitazone (10 μmol/L) +GW9662 (10 μmol/L), p38MAPK specific inhibitor SB203580 (10 μmol/L), SB203580 (10 μmol/L)+ rosiglitazone(10 μmol/L) for 2 hours followed by epidermal growth factor (EGF) stimulation. Protein expressions of p38, phuspho-p38 (p-p38) and proliferating cell nuclear antigen (PCNA) were detected by Western blot. p38 mRNA was examined by RT-PCR. Expression of c-fos and c-jun was observed by immunocytochemistry. Results (1) EGF markedly up-regulated the expressions of p38, p-p38, PCNA, c-fos anti c-jun compared with control group (P<0.01). (2) Compared with EGF treated group, rosiglitazone significantly reduced p38 activation and mRNA expression (P<0.01, respectively). Rosiglitazone, rosiglitazone+SB203580 could significantly down-regulated p-p38, PCNA, c-fos and c-jun expression (P<0.01, respectively) with no significant difference between these two groups. (3) GW9662 partially reversed the reduction effect of rosiglitazone. Conclusions Rosiglitazone can inhibit proliferation of autosomal dominant polycystic kidney disease cyst-lining epithelial cells partially through down-regulating p38 activation and reducing c-fos, c-jun and PCNA expression. The above effect of rosiglitazone is in part PPARγ-independcnt. 相似文献
130.
ΔNp63蛋白在膀胱移行上皮癌中的表达及其临床意义 总被引:3,自引:1,他引:2
目的 :探讨 p5 3基因家族新成员截短型p6 3(△Np6 3)在膀胱癌组织中的表达及其意义。 方法 :采用免疫组织化学SP法检测 4 0例膀胱移行上皮癌 (TCC)、6例膀胱内翻性乳头状瘤和 8例正常膀胱移行上皮中△Np6 3的表达 ,并分析△Np6 3表达与膀胱癌病理类型、临床分期的关系。 结果 :正常膀胱移行上皮、膀胱内翻性乳头状瘤、TCC中△Np6 3的阳性表达率分别为 37.5 % (3/ 8)、6 6 .7% (4/ 6 )、10 0 % (40 / 4 0 ) ,组间差异有统计学意义 (P <0 .0 1)。TCCG3 级与G2 级△Np6 3的强阳性、中度阳性表达率显著高于G1级 (P <0 .0 1)。Ta~T1期以△Np6 3弱阳性为主 (6 6 .7% ) ,随TCC浸润程度的增加 ,△Np6 3染色强度逐渐增强。T2 期△Np6 3强阳性表达率为 35 .3% ,T3 ~T4期增至 6 3.6 %。结论 :△Np6 3在TCC中高表达 ,与TCC病理分级、临床分期密切相关 ;△Np6 3可能参与TCC的发生、发展 ,是评估TCC预后的潜在因素之一。 相似文献