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81.
U. Müller W. Queißer Ch. Keßel F. Willig 《Journal of molecular medicine (Berlin, Germany)》1975,53(22):1083-1084
Zusammenfassung Bei 26 Fällen mit essentieller Paraproteinämie wurde die cytochemische Aktivität der Adenosintriphosphatase (ATPase) in den Plasmazellen des Knochenmarks untersucht. 15 Fälle zeigten eine erniedrigte und 11 Patienten eine normale ATPase-Aktivität. Die Untersuchungen zeigen, daß die Erniedrigung der ATPase für die Diagnostik des Plasmocytoms nicht spezifisch ist.Herrn Prof. Dr. W. Hoffmeister, Mannheim, zum 65. Geburtstag. 相似文献
82.
胰岛素样生长因子系统是一个由配体、受体、结合蛋白及蛋白酶构成的复杂网络,会受到诸多因子的调节.该系统中的胰岛素样生长因子结合蛋白在不同细胞的增殖和分化中起着重要的作用.临床及体内外研究表明胰岛素抵抗形成过程中,IGFBP出现异常表达.IGFBP通过不同机制抑制或促进胰岛素抵抗的形成. 相似文献
83.
目的观察槲皮素(QUE)对柔红霉素(DNR)所致小鼠心肌损伤的保护作用.方法 52只小鼠分5个实验组,1组作为空白对照组.1组用DNR诱导小鼠心肌损伤;1组用QUE灌胃给药后再用DNR诱导心肌损伤作为保护组;1组只给QUE灌胃作为保护对照组;1组给予DMSO灌胃作为溶剂对照组.观察各组小鼠的血清心肌酶谱、心肌和血清中脂质过氧化产物丙二醛(MDA)的含量及超氧化物歧化酶(SOD)活性的变化.观察心脏大体改变,并制备病理切片,HE染色后,光镜下观察心肌形态学变化.结果 DNR组小鼠的血清心肌酶谱显著升高,血清和心肌中MDA含量显著增高,SOD活性降低,引起心脏充血、水肿,心肌颗粒变性,灶性出血、坏死.而QUE保护组的心肌酶升高程度明显降低、血清和心肌组织中MDA含量无明显增加,SOD活性不降低,心肌无明显出血灶及颗粒变性.结论槲皮素对柔红霉素诱导的小鼠心肌损伤有保护作用.其机理可能与清除氧自由基、抗脂质过氧化损伤有关. 相似文献
84.
滋养细胞的有限侵袭对于正常的妊娠至关重要,其侵入机制与肿瘤细胞的转移相似,但与肿瘤细胞不同的是滋养层细胞的侵袭受母体及自身的多种旁分泌和自分泌因子的严格网络级联调控[1,2],要成功地侵入,绒毛外滋养层必须执行大量功能:母体螺旋动脉改建;耐受低氧,增殖、凋亡、分化,黏附并消化细胞外基质,移动并和母体免疫系统相互作用。其中每一种功能都具有错综复杂的控制系统,因此,滋养层的侵入是一个对抗机制精细调控的平衡。 相似文献
85.
CD3AK细胞过继免疫治疗的实验研究 总被引:10,自引:1,他引:10
目的: 分析抗CD3分子的单克隆抗体 (mAb)yCD3的免疫学特性和生物学活性, 观察其激活的免疫活性细胞CD3AK体外及动物体内的抑瘤作用。方法: 用流式细胞术(FCM)测定yCD3的特异性, 以及CD3AK细胞的免疫表型和产生细胞因子的情况。用 3H -TdR法测定yCD3对淋巴细胞转化的作用; 乳酸脱氢酶法 (LDH)测定CD3AK细胞的体外细胞毒活性。建立荷瘤小鼠模型, 观察静脉注射CD3AK细胞后肿瘤生长的情况、转移灶数量和小鼠存活天数。结果: yCD3与T细胞呈特异性反应, 5μgyCD3可竞争抑制 70%的标准抗CD3抗体与细胞表面CD3分子的结合。yCD3刺激外周血淋巴细胞增殖的有效浓度为 8μg/L, 并与IL- 2、抗CD28抗体有协同作用。活化的CD3AK细胞中CD3 、CD8 和CD25 细胞增多; 产生IL- 2和IFN γ的CD3 细胞均有不同程度的增加, 在抗CD28抗体协同刺激下分别增加 3. 29和 2. 47倍。当效靶细胞比为 80∶1时, CD3AK细胞对体外肿瘤细胞杀伤的百分率为 57. 54%。分组观察荷瘤动物, CD3AK细胞治疗组的抑瘤率为 33. 17%, 对小鼠肿瘤肺转移的抑制率为39. 70%, 与LAK细胞联合治疗的疗效更显著。结论: yCD3可活化T细胞, 诱导的CD3AK细胞在体外及动物体内显示抑制肿瘤的作用, 在临床抗肿瘤过继性免疫治疗中具有重要意义。 相似文献
86.
Koukoulis G Ke Y Henley JD Cummings OW 《Archives of pathology & laboratory medicine》2001,125(10):1331-1334
CONTEXT: The pathology of small bowel obstruction in Crohn disease has not been studied extensively. Stricture formation has been attributed mainly to fibrosis, although muscularization of the submucosa has been discussed previously. OBJECTIVE: To identify additional pathologic changes in Crohn disease that could be involved in the formation of strictures. DESIGN: We reviewed 50 ileal resections from patients with Crohn disease. The histopathologic slides were reviewed initially without knowledge of the macroscopic or clinical findings. We identified an unusual muscular proliferation that we refer to as obliterative muscularization of the submucosa, defined as a thick and continuous muscle layer from the mucosal base to the muscularis propria that is at least 1 cm in length. Subsequently, histopathologic findings were correlated with macroscopic and clinical findings. RESULTS: Obliterative muscularization of the submucosa was present in 14 specimens, and in 11 of these 14 it was topographically restricted to strictures. Submucosal fibrosis was observed in sections from adjacent regions. Obliterative muscularization of the submucosa, including thick-walled vessels and hyperplastic nerves but not prominent scarring, was more common in specimens with strictures; the difference was statistically significant (P <.001). CONCLUSIONS: Obliterative muscularization of the submucosa may be pathogenetically involved in the formation of strictures either directly by causing a sustained spasm, or indirectly by minimizing the vasoprotective role of the submucosa, impairing repair and enhancing scarring. 相似文献
87.
Genetic basis for individual variations in pain perception and the development of a chronic pain condition 总被引:11,自引:0,他引:11
Diatchenko L Slade GD Nackley AG Bhalang K Sigurdsson A Belfer I Goldman D Xu K Shabalina SA Shagin D Max MB Makarov SS Maixner W 《Human molecular genetics》2005,14(1):135-143
Pain sensitivity varies substantially among humans. A significantpart of the human population develops chronic pain conditionsthat are characterized by heightened pain sensitivity. We identifiedthree genetic variants (haplotypes) of the gene encoding catecholamine-O-methyltransferase(COMT) that we designated as low pain sensitivity (LPS), averagepain sensitivity (APS) and high pain sensitivity (HPS). We showthat these haplotypes encompass 96% of the human population,and five combinations of these haplotypes are strongly associated(P=0.0004) with variation in the sensitivity to experimentalpain. The presence of even a single LPS haplotype diminishes,by as much as 2.3 times, the risk of developing myogenous temporomandibularjoint disorder (TMD), a common musculoskeletal pain condition.The LPS haplotype produces much higher levels of COMT enzymaticactivity when compared with the APS or HPS haplotypes. Inhibitionof COMT in the rat results in a profound increase in pain sensitivity.Thus, COMT activity substantially influences pain sensitivity,and the three major haplotypes determine COMT activity in humansthat inversely correlates with pain sensitivity and the riskof developing TMD. 相似文献
88.
Two-and-half-month-old female rats were subjected to right hindlimb immobilization or served as controls for 0, 1, 2, 8, 14, and 20 weeks. The right hindlimb was immobilized by bandaging it against the abdomen, thus unloading it. Cancellous bone histomorphometry was performed on microradiographs and double-fluorescent labeled 20 microns sections of the distal femoral metaphyses. Primary spongiosa bone loss occurred rapidly by 2 weeks, and secondary spongiosa bone loss occurred rapidly by 8 weeks of immobilization, and then equilibrated at 60% less bone mass than age-related controls. The negative bone balance induced by immobilization was caused by transient increase in bone resorption, decrease in bone formation, and longitudinal bone growth. The dynamic data of secondary spongiosa cancellous bone showed that percent eroded perimeter was transiently elevated by 55 to 82% between 1 and 8 weeks, percent labeled perimeter was transiently depressed by 32% to 50% between 1 and 14 weeks, mineral apposition rate was depressed by 23% and 19% at 1 and 2 weeks, and bone formation rate-bone area referent was transiently depressed by 35% and 59% at 1 and 2 weeks. All the above parameters were at age-related control levels by 20 weeks of immobilization. However, bone formation rate-tissue area referent was depressed (-65%) throughout the study. Immobilization depressed completely longitudinal bone growth by 2 weeks and remained so. Only 0.65 mm of new metaphysis was generated in the immobilized versus 2.1 mm in controls during the study period. The immobilization induced an early cancellous bone loss which equilibrated at a new steady state with less bone and a normal (age-related control) bone turnover rate. When these findings were compared to an earlier study of 9-month-old virgin females subjected to right hindlimb immobilization up to 26 weeks, we found the adaptive responses of the cancellous bone were identical except that they occurred earlier and equilibrated sooner in younger rats. 相似文献
89.
BRANDOM B. W.; STILLER R. L.; COOK D. R.; WOELFEL S. K.; CHAKRAVORTI S.; LAI A. 《British journal of anaesthesia》1986,58(11):1210-1213
The pharmacokinetics of atracurium were studied in infants andchildren anaesthetized with isoflurane and nitrous oxide inoxygen. There were no significant differences in volume of distribution(area) (139 v. 152 ml kg1), clearance (5.1 v. 5.3 mlkg1 min1), T (2.1 v. 2.0 mim), or Tß(19.1 v. 20.3 min) between children with normal hepatic andrenal function and those with moderately impaired hepatic functionpresenting for hepatic transplantation. There were significantdifferences in volume of distribution (area) (176 v. 139 mlkg1) and in clearance of atracurium (9.1 v.5.1 ml kg1min1) between infants and children with normal excretoryfunction. In infants the clearance of atracurium in ml m1min1 (153 v. 133) tended to be greater and the T andTß tended to be shorter (1.0 v. 2.0 and 13.6 v. 19.1)than in children with normal excretory function; however, thesetrends did not reach statistical significance. Plasma laudanosineconcentration was around 100 ng ml1 greater in patientswith liver disease than in normal children from 1545min following a bolus of atracurium 0.5 mg kg1. 相似文献
90.
目的 调查河南省儿童青少年遗尿症的情绪和行为问题的现况及其影响因素。 方法 从2019年10月—2020年3月,采用分层随机整群抽样方法抽取河南某县5所中小学校,采用一般资料调查表、长处和困难问卷及儿童睡眠调查表进行调查,对影响遗尿患儿情绪和行为的因素进行单因素、多因素分析。 结果 实际发放问卷4 500份,回收4 120份,有效问卷3 912份,有效回收率为94.95%。调查结果显示有7.82%儿童患有遗尿症。遗尿组的情绪症状、多动和困难总分得分明显高于正常组(P<0.001),两组品行问题、同伴交往和社会行为得分的比较差异无统计学意义(P>0.05)。Pearson相关分析结果显示,遗尿儿童和青少年的困难总分与打鼾、夜间呼吸问题、嗜睡、注意力缺陷、睡眠总分均存在正相关关系(P<0.05)。多元线性回归结果显示睡眠呼吸紊乱、照顾者文化程度低、便秘、学习成绩较差是遗尿患儿情绪和行为问题的影响因素。 结论 遗尿患儿情绪和行为问题的检出率高,影响因素是睡眠呼吸紊乱、照顾者文化程度低、孩子学习成绩差、便秘,应引起关注。 相似文献