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21.
立位X线胸片可敏感而特异地显示膈下游离气体 ,对开放性结肠直肠切除术后空腔脏器出现破损是一项有效的检查 ,但由于剖腹术后气腹自然吸收所需要的时间未知 ,其作用尚未被确定。本次试验的目的即在于确定这一时间。 3个月内连续 92例接受了连续性结肠直肠切除术的病人 (8例拒绝合作 ,9例采用了腹腔镜技术 )中的 75例参与了这次试验 (平均年龄 6 2 1岁 ,男∶女 =1 3∶1) ,手术指征分别为直肠癌 6例 ,憩室病 2例 ,肠道炎症 2例 ,放疗引起狭窄 3例 ,功能性疾患 (慢性运输性便秘 ,直肠脱垂 ) 2例 ,其它 (家族性腺瘤息肉、乙状结肠扭转、短… 相似文献
22.
LT Lucato AM McKinney J Short M Teksam CL Truwit 《Journal of Medical Imaging and Radiation Oncology》2006,50(4):364-368
A 35‐year‐old woman presented with neurotoxicity correlated to an i.v. regimen of 5‐fluorouracil as episodes of acute confusional state and abnormalities of symmetrically restricted diffusion in the periventricular white matter and corpus callosum. On discontinuing the medication, the areas of severely restricted diffusion had entirely resolved, with minimal residual T2 signal abnormality. In this case, immediate discontinuation of the chemotherapeutic agent apparently reversed the patient's symptoms and findings on MRI. The scant information available in the published literature regarding this phenomenon is reviewed with regard to 5‐fluorouracil. 相似文献
23.
Wang LM Zhang Q Zhu W He C Lu CL Ding DF Chen ZY 《第二军医大学学报》2005,26(11):1299-1299
Glial cell line-derived neurotrophic factor (GDNF) plays a critical role in neurodevelopment and survival of midbrain dopaminergic and spinal motor neurons in vitro and in vivo. The biological actions of GDNF are mediated by a two-receptor complex consisting of a glycosylphosphatidylinositol-linked cell surface molecule, the GDNF family receptor alpha 1 (GFR alpha 1), and receptor protein tyrosine kinase Ret. Although structural analysis of GDNF has been extensively examined, less is known about the structural basis of GFR alpha 1 function. In this study, based on evolutionary trace method and relative solvent accessibility prediction of residues, a set of trace residues that are solvent-accessible was selected for site-directed mutagenesis. A series of GFR alpha 1 mutations was made, and PC12 cell lines stably expressing different GFR alpha 1 mutants were generated. According to the survival and differentiation responses of these stable PC12 cells upon GDNF stimulation and the GDNF- GFR alpha 1-Ret interaction assay, residues 152NN153, Arg259, and 316SNS318 in the GFR alpha 1 central region were found to be critical for GFR alpha 1 binding to GDNF and eliciting downstream signal transduction. The single mutation R259A in the GFR alpha 1 molecule simultaneously lost its binding ability to GDNF and Ret. However N152A/N153A or S316A/N317A/ S318A mutation in the GFR alpha 1 molecule still retained the ability to bind with Ret. These findings suggest that distinct structural elements in GFR alpha 1 may be involved in binding to GDNF and Ret. 相似文献
24.
25.
Pharmacokinetics of apomorphine in parkinsonian patients 总被引:1,自引:0,他引:1
E. Nicolle P. Pollak F. Serre-Debeauvais P. Richard CL Gervason E. Broussolle and M. Gavend 《Fundamental & clinical pharmacology》1993,7(5):245-252
Summary— Apomorphine, a dopamine agonist, has been used efficiently in parkinsonian patients to treat severe levodopa-induced on-off phenomenon. Motor improvement has been obtained both with continuous subcutaneous (SC) infusions, and multiple SC injections. So as to assist in the understanding of the clinical results, we studied the peripheral pharmacokinetics of apomorphine in 20 patients after intravenous (IV) or SC injections in the anterior abdominal wall and in the thigh at various doses, or SC infusion. Plasma apomorphine levels were measured by high-performance liquid chromatography with electrochemical detection. After an SC injection in the abdominal wall, the Tmax was brief (16 ± 11 min) the drug was rapidly cleared from the plasma and had a short plasma half-life (69.7 ± 25.8 min). The AUC was similar following SC and IV injections, suggesting that apomorphine was completely absorbed from subcutaneous tissue. Inter-subject variability in drug absorption was large. We noticed a trend towards a more complete absorption following injection in the abdominal wall rather than in the thigh. In patients chronically treated by continuous SC infusion, the apparent plasma half-life was five times longer than that following SC or IV injections. These pharmacokinetic data may explain the rapid onset and brief duration of clinical effects, and the usefulness of individual titration for intermittent SC apomorphine injections, and the smoother motor response obtained with continuous SC infusions. 相似文献
26.
目的:缝隙连接蛋白43对维持心肌细胞的连接通讯功能、电信号传导和正常的节律性收缩起重要作用,其表达和分布的异常是多种室性心律失常的解剖学基础,建立小型猪急性心肌梗死模型.观察自体骨髓间充质干细胞移植后室性心动过速的发生及心肌缝隙连接蛋白43的表达方法:实验于2006-01/2007-01在河北省人民医院导管室完成。①材料:选取8~12月龄小型猪22头,由河北医科大学实验动物中心提供,体质量20~30 kg,随机数字表法分为细胞移植组12头、模型对照组10头.实验过程中对动物的处置符合动物伦理学际准②实验方法:无菌条件下抽取猪双侧股骨骨髓20 mL,percoll法 贴壁法分离培养骨髓间充质干细胞,待细胞生长达75%融合时用胰酶消化传代。将传至第2代细胞加入终浓度为10μmol/L的5-氮胞苷进行诱导,用胶体金标记12 h后继续培养20 d用于移植:两组小型猪均采用球囊堵闭法建立急性心肌梗死模型.心电图监测示相关至少2个导联ST段抬高大于0.2 mV、术后血肌钙蛋白和肌酸磷酸激酶同工酶升高超过正常的两倍为建模成功标准:细胞移植组于造模成功后经OTW球囊于第一对角支远端1 cm处再次阻断血流,注入经胶体金标记的10×10~7个骨髓间充质干细胞。③实验评估:于细胞移植后2 h及4周行电生理程序刺激.观察室性心动过速的发生情况。末次电生理检查后、采用免疫组化染色法检测心肌缝隙连接蛋白43的表达.计算其积分吸光度值。结果:①模型建立指标检测:与术前比较.造模后所有小型猪血肌钙蛋白含量和肌酸磷酸激酶同工酶活性均增高,峰值浓度分别为(21.3±3.6)μg/L和(178.3×41.4)IU/L,术中心电图ST段平均抬高(10.67±1.43)mm.证明急性心肌梗死模型成功建立。②骨髓间充质干细胞移植后室性心动过速的发生情况:与模型对照组诱发出室性心动过速的动物数量比较,术后2 h细胞移植组无明显变化(X~2=0.201,P=0.650),术后4周细胞移植组明显降低(X~2=4.455.P=0.035)。②骨髓间充质干细胞移植后梗死心肌缝隙连接蛋白43的表达:术后4周移植到梗死心肌的骨髓间充质干细胞与宿主心肌生长为一体,移植部位颜色变黑,苏木精-伊红染色示移植细胞的胞浆呈紫红色。细胞移植组心肌梗死区缝隙连接蛋白43积分吸光度值明显高于模型对照组(t=16,82.P=0.00),细胞移植组中未发生室性心动过速小型猪的梗死心肌缝隙连接蛋白43的表达明显高于发生室性心动过速小型猪(t=5.06,P=0.00)。结论:自体骨髓间充质干细胞移植可促进急性心肌梗死猪心肌缝隙连接蛋白43的表达,其表达程度可能与急性心肌梗死室性心动过速的发生有关。 相似文献
27.
紫杉醇药物涂层支架植入术后患者外周血单核细胞中热休克蛋白70的变化:生物材料临床应用近期效果随访 总被引:1,自引:0,他引:1
目的:植入材料、靶血管病变特征、术前状态、炎症因子及急性期蛋白均对急性冠状动脉综合征接受支架材料介入治疗后的效果有影响,为验证紫杉醇涂层支架临床应用后材料及宿主的相关反应,实验观察了接受紫杉醇涂层支架介入治疗的急性冠状动脉综合征患者的外周血热休克蛋白70水平变化,并分析其临床意义。方法:①连续性入选2004-12/2006-03在江苏大学附属人民医院行经皮冠状动脉介入治疗的78例急性冠状动脉综合征患者,全部病例均置入紫杉醇药物涂层支架。采用流式细胞仪测定症状发作平均(34.1±16.2)h的外周血单核细胞热休克蛋白70阳性表达水平。②所有患者随访至术后6个月,出现心源性死亡、再次心肌梗死、再发心绞痛、再次血运重建术和继发心衰等主要心脏不良事件者为近期预后不良组,无上述情况者判定为近期预后良好组,用logistic多元回归法分析术前状态、靶血管病变特征、植入支架的各项参数及外周血热休克蛋白70水平与主要心脏不良事件发生率的关系,并以同期健康体检者20例为正常对照组。结果:68例患者完成随访进入结果分析。①外周血热休克蛋白70水平:急性心肌梗死患者和不稳定型心绞痛患者比较差异无统计学意义(P>0.05),但均显著高于正常对照组(P<0.05)。②在多变量的logistic回归分析中,外周血热休克蛋白70独立于其危险因素,能预测急性冠状动脉综合征患者经皮冠状动脉介入治疗后近期主要心脏不良事件发生率(OR值为0.904,P<0.05)。结论:回归分析结果提示,应用紫杉醇涂层支架临床治疗近期效果评估中,外周血热休克蛋白70水平高的急性冠状动脉综合征患者近期心脏事件发生率较高,说明外周血热休克蛋白70可能成为判断紫杉醇涂层支架介入治疗后不良事件发生率的独立因素之一。 相似文献
28.
目的:骨唾液酸蛋白在骨矿化形成方面扮演重要角色,实验观察其是否能诱导体外培养的人骨髓间充质干细胞向成骨细胞分化。方法:实验于2005—10/2006—12在解放军广州军区广州总医院医学实验科完成。①材料来源:选取在本院体检的健康志愿者2人,对本实验均知情同意。采用Ni-NTA亲和纯化技术,从本室构建的毕赤酵母GS115/pPICZaA-hbsp发酵上清中纯化重组人骨唾液酸蛋白。②实验方法:对健康志愿者进行髂骨穿刺抽取骨髓液,采用贴壁法培养得到骨髓间充质干细胞。设立4组:骨唾液酸蛋白组添加0.1nmol/L骨唾液酸蛋白;成骨诱导液组添加10nmol/L地塞米松、10mmol/L磷酸甘油、50mg/L抗坏血酸;联合组添加上述两组的所有试剂;空白对照组不添加任何处理因素;各组均处理细胞12d。⑧实验评估:光镜及电镜观察培养的细胞形态;以细胞计数法测定生长曲线,应用流式细胞仪分析细胞周期,采用免疫荧光细胞化学法和流式细胞分析检测干细胞标志物STRO-1的表达;生化试剂盒测定碱性磷酸酶活性;von Kossa染色法检测钙沉积。结果:①单个骨髓间充质干细胞为长梭形,经骨唾液酸蛋白处理后细胞大而扁平,原来密集的克隆分散开。②与空白对照组比较,骨唾液酸蛋白组引起细胞生长曲线右移,细胞Go/G,期比例平均增加12.09%(P〈0.01),S期比例减少65.92%(P〈0.01),STRO-1阳性细胞百分率下降26.54%(P〈0.01)。⑧与空白对照组比较,骨唾液酸蛋白组细胞碱性磷酸酶活性增加50.0%,成骨诱导液组增加59.5%,联合组增加71.43%,并且随着处理时间的延长,活性增加越显著。④空白对照组细胞vonKossa染色呈阴性,其余各组均呈阳性。其中联合组的黑色矿化结节体积最大、数目最多;骨唾液酸蛋白组的结节体积较小、数目较少;成骨诱导液组居中。结论:骨唾液酸蛋白对人骨髓间充质干细胞有促进成骨分化和矿化作用,且与成骨诱导液联用效果更佳。 相似文献
29.
Background
The purpose of this study was to determine the effects of the pre-workout supplement Assault? (MusclePharm, Denver, CO, USA) on upper and lower body muscular endurance, aerobic and anaerobic capacity, and choice reaction time in recreationally-trained males. Subjective feelings of energy, fatigue, alertness, and focus were measured to examine associations between psychological factors and human performance.Methods
Twelve recreationally-trained males participated in a 3-week investigation (mean +/- SD, age: 28 +/- 5 y, height: 178 +/- 9 cm, weight: 79.2 +/- 15.7 kg, VO2max: 45.7 +/- 7.6 ml/kg/min). Subjects reported to the human performance laboratory on three separate occasions. All participants completed a baseline/familiarization day of testing that included a maximal graded exercise test for the determination of aerobic capacity (VO2max), one-rep maximum (1-RM) for bench and leg press to determine 75% of 1-RM, choice reaction tests, and intermittent critical velocity familiarization. Choice reaction tests included the following: single-step audio and visual, one-tower stationary protocol, two-tower lateral protocol, three-tower multi-directional protocol, and three-tower multi-directional protocol with martial arts sticks. Subjects were randomly assigned to ingest either the supplement (SUP) or the placebo (PL) during Visit 2. Subjects were provided with the cross-over treatment on the last testing visit. Testing occurred 20 min following ingestion of both treatments.Results
Significant (p < 0.05) main effects for the SUP were observed for leg press (SUP: 13 ± 6 reps, PL: 11 ± 3 reps), perceived energy (SUP: 3.4 ± 0.9, PL: 3.1 ± 0.8), alertness (SUP: 4.0 ± 0.7, PL: 3.5 ± 0.8), focus (SUP: 4.1 ± 0.6, PL: 3.5 ± 0.8), choice reaction audio single-step (SUP: 0.92 ± 0.10 s, PL: 0.97 ± 0.11 s), choice reaction multi-direction 15 s (SUP: 1.07 ± 0.12 s, PL: 1.13 ± 0.14 s), and multi-direction for 30 s (SUP: 1.10 ± 0.11 s, PL: 1.14 ± 0.13 s).Conclusions
Ingesting the SUP before exercise significantly improved agility choice reaction performance and lower body muscular endurance, while increasing perceived energy and reducing subjective fatigue. These findings suggest that the SUP may delay fatigue during strenuous exercise. 相似文献30.
Suneeti Nathani Iyer Hailey Denson Nicole Lazar D. Kimbrough Oller 《Clinical linguistics & phonetics》2016,30(6):470-488
Although parental volubility, or amount of talk, has received considerable recent attention, infant volubility has received comparatively little attention despite its potential significance for communicative risk status and later linguistic and cognitive outcomes. Volubility of 16 typically developing infants from 2 to 11 months of age was longitudinally investigated in the present study across three social circumstances: parent talking to infant, parent not talking to infant and parent talking to interviewer while the infant was in the room. Results indicated that volubility was least in the Interview circumstance. There were no significant differences in volubility between the parent Talk and No Talk circumstances. Volubility was found to reduce with age. These results suggest that infants vocalise in a variety of circumstances, even when no one talks to or interacts with them. The presence of a stranger or perhaps overhearing adults speaking to each other, however, may significantly reduce infant volubility. 相似文献