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991.
目的 探讨环氧酶-2抑制剂对关节炎大鼠小肠黏膜的影响。方法 将32只雄性SD大鼠随机分为空白对照组、造模对照组、空白给药组和造模给药组,造模对照组、造模给药组给予弗氏完全佐剂右后足跖注射,空白对照组、空白给药组注射等量生理盐水。1周后造模给药组、空白给药组给予选择性环氧酶-2抑制剂塞来昔布(溶于1%甲基纤维素)灌胃28 d,空白对照组、造模对照组给予等量溶剂。处死大鼠后观察小肠黏膜大体损伤、病理评分,酶联免疫吸附试验检测末段小肠前列腺素浓度。结果 造模对照组与造模给药组模型复制第7天的足周径比较,差异无统计学意义(P>0.05),但两组分别与空白对照组和空白给药组比较,差异有统计学意义(P <0.05),空白对照组与空白给药组比较,差异无统计学意义(P>0.05)。空白对照组与造模对照组小肠黏膜损伤面积比较,差异有统计学意义(P <0.05),空白给药组与空白对照组比较,差异有统计学意义(P <0.05)。造模对照组、空白给药组和造模给药组组间小肠黏膜病理评分比较,差异无统计学意义(P>0.05),且空白对照组与其他3组比较,差异有统计学意义(P &... 相似文献
992.
目的 探讨急性脑梗死患者血清补体C1q/肿瘤坏死因子相关蛋白3(CTRP-3)、D-二聚体、可溶性髓样细胞触发受体2(sTREM2)水平及相关临床特征与溶栓后出血性转化(HT)的关系。方法 回顾性分析2018年9月—2022年9月在青海省人民医院接受溶栓治疗的120例急性脑梗死患者的临床资料,根据患者溶栓后是否发生HT分为HT组(30例)、非HT组(90例)。比较两组患者的临床资料及血清CTRP-3、D-二聚体、sTREM2水平。采用多因素逐步Logistic回归分析急性脑梗死患者溶栓后发生HT的危险因素;绘制受试者工作特征(ROC)曲线,分析急性脑梗死患者溶栓后HT预测模型预测HT发生的价值。结果 HT组心房颤动(以下简称房颤)、大面积脑梗死、入院NIHSS评分≥ 15分占比高于非HT组(P <0.05),血清CTRP-3水平低于非HT组(P <0.05),D-二聚体、sTREM2水平高于非HT组(P <0.05)。血清CTRP-3、D-二聚体、sTREM2水平预测急性脑梗死患者溶栓后发生HT的敏感性分别为66.7%(95% CI:0.598,0.756)、70.0%(95% CI:0.607,0.812)、80.0%(95% CI:0.714,0.889),特异性分别为73.3%(95% CI:0.636,0.821)、86.7%(95% CI:0.778,0.923)、86.7%(95% CI:0.747,0.942)。多因素Logistic逐步回归分析结果显示,房颤[O^R=1.237(95% CI:1.103,1.387)]、大面积脑梗死[O^R=2.338(95% CI:1.292,4.231)]、入院NIHSS评分≥ 15分[O^R=2.087(95% CI:1.231,3.538)]、CTRP-3 ≤ 269.265 μg/L [O^R=3.006(95% CI:1.508,5.992)]、D-二聚体≥ 2.625 mg/L [O^R=2.649(95% CI:1.374,5.107)]、sTREM2 ≥ 314.675 ng/L [O^R=2.328(95% CI:1.411,3.841)]是急性脑梗死患者溶栓后发生HT的危险因素(P <0.05)。根据多因素Logistic逐步回归分析结果建立急性脑梗死患者溶栓后HT预测模型,Logit(P) = -33.887 + 0.213×房颤+ 0.849×大面积脑梗死+0.736×入院NIHSS评分+ 1.101×CTRP-3 + 0.974×D-二聚体+ 0.845×sTREM2;ROC曲线分析结果表明,预测模型预测HT发生的敏感性为93.3%(95% CI:0.841,0.991),特异性为87.8%(95% CI:0.808,0.976)。结论 血清CTRP-3、D-二聚体、sTREM2水平与急性脑梗死患者溶栓后HT有关,预测价值较高,且急性脑梗死患者溶栓后HT预测模型预测HT优于各项指标单独预测。 相似文献
993.
目的 探讨脂联素(APN)、直接胆红素(DB)、甘油三酯(TG)及三者联合对 2 型糖尿病(T2DM)患者大血管病变的诊断价值。方法 选取120例T2DM患者,根据是否合并大血管病变将其分为T2DM组(62 例)和 T2DM+大血管病变组(58 例)。比较两组的临床资料;采用非条件多因素逐步Logistic回归分析T2DM患者合并大血管病变的风险因素;绘制受试者工作特征(ROC)曲线评估APN、DB、TG及三者联合对T2DM患者合并大血管病变的诊断效能。结果 非条件多因素逐步Logistic回归分析结果显示,■是T2DM患者合并大血管病变的危险因素(P <0.05);■是T2DM患者合并大血管病变的保护因素(P <0.05)。ROC曲线分析结果显示,当APN ≤ 5.870 nmol/mL时,诊断T2DM患者合并大血管病变的曲线下面积(AUC)为0.718,敏感性为70.7%(95% CI:0.571,0.815),特异性为61.3%(95% CI:0.480,0.713);当DB ≤ 14.205 mol/L 时,AUC 为 0.772,敏感性为 74.1% (95% C... 相似文献
994.
目的 探讨血清骨膜蛋白(PN)和骨硬化蛋白(SOST)与老年 2 型糖尿病(T2DM)患者骨密度的关系。方法 选取2020年8月—2022年3月海南医学院第二附属医院收治的192例老年T2DM患者作为研究对象,依据骨密度值分为骨量正常组、骨量减少组及骨质疏松组,每组64例。比较3组患者的临床资料,血清PN、SOST、25羟维生素D3[25(OH)D3]、骨钙素(OST)及I型胶原氨基端前肽(PINP)水平。多因素Logistic回归分析影响老年T2DM患者骨质疏松发生的危险因素。绘制受试者工作特征(ROC)曲线,以ROC曲线下面积(AUC)评价血清PN、SOST及两者联合对老年T2DM患者骨质疏松的诊断价值。结果 骨量正常组、骨量减少组及骨质疏松组HbA1c、HDL-C、PN、SOST、25(OH)D3、OST及PINP水平比较,差异有统计学意义(P <0.05),骨质疏松组HbA1c、PN、SOST、OST及PINP水平高于骨量正常组和骨量减少组(P <0.05),骨质疏松组HDL-C、25(OH)D 相似文献
995.
宫颈粘液过氧化物酶在月经周期中的变化规律 总被引:3,自引:1,他引:2
本文对29例月经周期正常妇女的宫颈粘液过氧化物酶进行了30个周期的研究。在月经周期不同时间测定宫颈粘液过氧化物酶(CMPx)活性及血清促黄体生成素(LH)、雌二醇(E_2)和孕酮(P)。结果表明:在排卵前三天酶活性明显下降,至排卵后一天开始上升。卵泡期,酶活性与E_2呈负相关(r=-0.67);黄体期,酶活性与P呈正相关(r=0.79)。本研究提示:1.CMPx在排卵周期具有特定的变化规律,其变化受体内激素水平影响,可作为预告排卵的指标。2.如简化测定方法,可为自然避孕提供新途径。 相似文献
996.
Mohammad Nasri-Sebdani Flavien Traoré Christian Cognard Daniel Potreau Jean -Pierre Poindessault Guy Raymond 《Pflügers Archiv : European journal of physiology》1990,416(1-2):106-112
The effects of tetracaine (10–50 M) and ryanodine (0.1–10 M) were tested on the slow outward K+ current (I
so) and the mechanical tension of isolated frog muscle fibres in a voltage-clamp device (double mannitol-gap) connected to a mechanoelectric transducer. In the concentration range tested, both drugs induced a simultaneous inhibition of tension and current. In all cases the effect on tension was twice that on current. The tetracaine-induced current and tension blocks were fully reversible and dose-dependent. In contrast the ryanodine effects on current and tension were not reversible and did not exhibit a dose dependence except for the delay before the onset of the response, which was shortened when the concentration was raised. Linear regression analysis of the time-dependent and dose-dependent effects of both drugs indicated a strong correlation between the decreases in tension and current. It is concluded that the slow outward current is partly under the control of the Ca2+ release from sarcoplasmic reticulum during contraction. 相似文献
997.
Rob A. Binkhorst Berend Oeseburg Maria T. E. Hopman 《European journal of applied physiology》1992,65(1):73-78
Summary The purpose of this study was to examine cardiovascular responses during arm exercise in paraplegics compared to a well-matched control group. A group of 11 male paraplegics (P) with complete spinal cord-lesions between T6 and T12 and 11 male control subjects (C), matched for physical activity, sport participation and age performed maximal arm-cranking exercise and submaximal exercise at 20%, 40% and 6070 of the maximal load for each individual. Cardiac output (Q
c) was determined by the CO2 rebreathing method. Maximal oxygen uptake was significantly lower and maximal heart rate (f
c) was sigificantly higher in P compared to C. At the same oxygen uptakes no significant differences were observed inQ
c between P and C; however, stroke volume (SV) was significantly lower andf
c significantly higher in P than in C. The lower SV in P could be explained by an impaired redistribution of blood and, therefore, a reduced ventricular filling pressure, due to pooling of venous blood caused by inactivity of the skeletal muscle pump in the legs and lack of sympathetic vasoconstriction below the lesion. In conclusion, in P maximal performance appears to have been limited by a smaller active muscle mass and a lower SV despite the higher c,max. During submaximal exercise, however, this lower SV was compensated for by a higherf
c and, thus at the same submaximal oxygen uptake,Q
c was similar to that in the control group. 相似文献
998.
Dr. Susumu Itoh MD Kazuhiro Marutani MD Shuichi Matsuo MD 《Digestive diseases and sciences》1992,37(8):1260-1267
We studied the histological and ultrastructural changes in the liver and alterations in the liver test results before, during, and after treatment with human interferon- from five patients with hepatitis B e antigen-positive chronic active hepatitis. A daily dose of 3×106 to 6×106 units of interferon- was given intravenously for four weeks. The total index of periportal and portal inflammation, intralobular degeneration, and focal necrosis before treatment was decreased significantly six months after treatment (P<0.05). Ultrastructurally, the structure of endoplasmic reticulum was irregularly shaped or fragmentally decreased during treatment, but these disappeared six or 12 months after treatment. Glycogen particles diminished greatly during treatment. The alanine aminotransferase concentrations in these patients increased during treatment. Serum albumin and cholinesterase levels decreased significantly at the fourth week of treatment (P<0.01) and at the third day (P<0.01) to the second week (P<0.05) of treatment, respectively. These results suggest that interferon- injures endoplasmic reticulum and glycogen areas and damages the cholinesterase activity in the early stage of treatment and protein synthesis in patients with hepatitis B e antigen-positive chronic active hepatitis. 相似文献
999.
Erik Kriek 《Journal of cancer research and clinical oncology》1992,118(7):481-489
Summary It is just about 50 years since the publication of the report on the toxicity and carcinogenicity of the potent carcinogenN-acetyl-2-aminofluorene (AAF). In 1940 very few reports on the carcinogenic activity of chemical compounds in experimental animals were available. The discovery of pure chemicals as carcinogens, such as AAF, azo dyes and benzo[a]pyrene, provided cancer researchers with a number of tools whereby the progressive changes involved in the induction of cancer could be studied in experimental systems. Contrary to the results with other carcinogens then known, AAF induced numerous types of tumors, but not at the site of application. This finding stimulated a great deal of interest in its use as an experimental carcinogen to study its metabolic fate and mechanism of action. During the following years an ever increasing number of reports appeared on the carcinogenicity of AAF in various species, on its metabolic fate, on the interaction of reactive metabolites with nucleic acids and proteins, and on its mutagenic activity. Particularly studies on the metabolism of AAF and the interaction with nucleic acids have contributed appreciably to our understanding of the mechanism of action of aromatic amines and also of other chemical carcinogens. It can be expected that AAF and its derivatives will continue to be used for specific applications in experimental cancer research. One of the most recent achievements is the preparation of site-specific AAF- and aminofluorene-modified DNA sequences for mutagenesis studies.Abbreviation AAF
N-acetyl-2-aminofluorenem
The Journal of Cancer Research and Clinical Oncology publishes in loose succession Editorials and Guest editorials on current and/or controversial problems in experimental and clinical oncology. These contributions represent exclusively the personal opinion of the author The Editors 相似文献
1000.
N. Negoro Y. Kanayama T. Takeda M. Fujisawa M. Okamura T. Inoue 《Rheumatology international》1989,8(6):273-277
Summary We measured 2-plasmin inhibitor-plasmin complexes (PI-PC) in plasma of patients with systemic lupus erythematosus (SLE) to examine the plasminogen activation in SLE. The plasma PI-PC level in 23 patients with SLE was significantly higher than that in 18 normal subjects (P<0.001) and the SLE patients with nephrotic syndrome had higher plasma PI-PC levels than those without nephrotic syndrome (P<0.01). In addition, the plasma PI-PC level was significantly correlated with the level of plasma C3 breakdown products (iC3b/C3dg) in the patients with SLE (r=0.53, P<0.01). These results suggest that plasminogen is activated in plasma of patients with SLE and that the plasminogen activation may be associated with the activation of complement in SLE. 相似文献