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11.
柯希煌  练克俭 《中国骨伤》2007,20(9):570-572
急性臂丛神经炎是一种少见病,但人们往往认识不足,在早期,易被误诊为神经根型颈椎病或胸廓出口综合征。为了提高对本病的认识,降低误诊和漏诊率,本文就急性臂丛神经炎的诊断、鉴别诊断与治疗进行综述。1诊断名词与病因急性臂丛神经炎,病因尚未明了,但却有典型的临床特征。最初由Parsonage等[1]和Turner等[2]报道为肩胛带综合征和麻痹性臂丛神经炎,后被称之为:Parsonage-Turner综合征。其他诊断名词有:急性臂丛神经炎,神经源性肌萎缩,术后原发性臂丛神经炎等[3,4]。  相似文献   
12.
目的初步观察用小分子干扰RNA(siRNA)沉默树突状细胞(DCs)恒定链(Ii)后,DCs疫苗的体外抗肿瘤效果。方法从小鼠骨髓分离骨髓前体细胞,细胞经100 ng/ml GM-CSF和100 ng/ml IL-4诱导培养6 d后,转染针对DCs Ii链特异的Ii-siRNA,转染后加用50 ng/ml TNF-α继续诱导细胞成熟48 h,然后分别用Western blot检测沉默效果及CCK-8试剂盒检测DCs刺激同种异体淋巴细胞增殖的能力;此外,DCs共转染Ii-siRNA和小鼠胃癌前体细胞MFC的总RNA后,与同种异体淋巴细胞共培养,通过ELISA检测培养上清IFN-γ/和IL-4的水平,并收集致敏淋巴细胞进行体外杀伤实验。结果Ii-siRNA明显抑制DCs Ii的表达。沉默Ii链能够增强DCs的淋巴细胞增殖能力,并促使淋巴细胞向Th1的方向漂移[IFN-γ:(5107±351)pg/ml,IL-4:(65±13)pg/ml,P<0.05]。淋巴细胞经共转染Ii-siRNA和MFC RNA的DCs激活后,明显而特异地杀伤靶肿瘤细胞(杀伤百分率: 66.94%±2.75%,P<0.05)。结论通过siRNA沉默DCs的Ii链可能是一种行之有效的增强抗肿瘤免疫的方法。  相似文献   
13.
目的探讨p38丝裂原活化蛋白激酶(p38MAPK)在链脲菌素诱导的糖尿病大鼠神经病理性痛中的作用。方法雌性Wistar大鼠31只,3月龄,体重180~220g,随机分为3组:对照组(C组,n=10)、糖尿病神经病理性痛组(D组,n=11)和p38MAPK抑制剂组(Ⅰ组,n=10)。D组、Ⅰ组单次腹腔注射链脲菌素65mg/kg制备糖尿病模型。糖尿病模型制备成功后,Ⅰ组尾静脉注射p38MAPK抑制剂SB203580 0.5mg/kg,1次/周,连续4周;C组和D组尾静脉注射等体积的生理盐水。给药4周后,测定机械缩足反应阈值(MWT)、左侧坐骨神经传导速率(NCV)、背根神经节(DRG)和脊髓的磷酸化p38MAPK水平。结果与C组比较,D组、Ⅰ组MWT下降,NCV减慢,伴有脱髓鞘现象,DRG和脊髓的磷酸化p38MAPK水平升高;与D组比较,Ⅰ组MWT升高,NCV增快,脱髓鞘程度减轻,DRG和脊髓的磷酸化p38MAPK水平下降。结论p38MAPK信号转导通路参与了糖尿病大鼠神经病理性痛的形成。  相似文献   
14.
Background: The passage of proteins across the glomerular filtration barrier is mainly determined by the size of the protein. In nephrotic syndrome (NS) the glomerular permselectivity is affected, causing proteinuria. Some authors suggest the existence of a generalized basement membrane defect. The permeability characteristics of the peritoneal basement membrane in children with NS are not known. Methods: The transperitoneal transport of proteins with a different molecular weight ({beta}2-microglobulin MW 11 800 D, albumin MW 69 000 D, IgG MW 160 000 D, and &agr;2-macroglobulin MW 820 000 D) was studied in a study group (group A) consisting of six stable nephrotic children (three with glomerulosclerosis and three with congenital nephrotic syndrome, one of them with mesangial sclerosis) and compared to a control group (group B) consisting of eight stable children on peritoneal dialysis. After a dwell of 6 h with Dianeal 1.36% dialysate and serum samples were collected. For each patient the dialysate to plasma (D/P) ratio of the four proteins were calculated. The D/P ratios of the nephrotic patients in group A were compared to the D/P ratios of the patients in the control group B. Data were expressed as mean ±SD. Results: The values for the D/P ratios (in percentage) of {beta}2-microglobulin, albumin, IgG and &agr;2-macroglobulin in group A were 19.6±9.9, 2.7±1.7, 1.6±0.9, and 0.5±0.4, compared to 24.9±10.2, 4.0±2.3, 2.2±1.2, and 0.7±0.3 in the control group B. The ratios were plotted against MW on a double logarithmic scale. In all patients a linear relationship between molecular weight and D/P ratio of the proteins was obtained. The D/P ratios of the study group did no differ significantly from the control group. Conclusion: We conclude that the size selectivity of the capillary permeability is not affected in the peritoneal membrane in children with NS due to glomerulosclerosis and congenital nephrotic syndrome.  相似文献   
15.
Routinely processed tissues from a series of benign and malignant thyroid lesions were immunohistochemically investigated with antibodies against p53 and mdm-2. p53 was immunolocalized in <10% of nuclei in 2/80 nodular goiters, 2/60 follicular adenomas, 26/68 follicular carcinomas, 7/40 papillary carcinomas, 3/10 “insular” carcinomas, and 10/31 anaplastic carcinomas. More than 10% positively stained nuclei were found in 2 widely invasive follicular, 2 insular, and 15 anaplastic carcinomas. All p53-positive cases showed a concomitant immunohistochemical mdm-2 expression; an immunohistochemical colocalization on serial section was demonstrated in 12 anaplastic carcinomas. Screening by polymerase chain reaction single-strand conformation polymorphism (PCR-SSCP) analysis of these 12 cases revealed no relevant mutations in the coding regions of exons 2–11 of the p53 gene. Additionally, 1 follicular adenoma, 6 follicular carcinomas (4 minimally and 2 widely invasive), 1 papillary, and 2 poorly differentiated insular carcinomas were mdm-2 positive without immunohistochemically detectable p53 expression. These results provide evidence that wild-type p53 expression in thyroid carcinomas may be associated with mdm-2 induced formation of stable complexes. However, the role of p53 mutations and p53 protein inactivation owing to other factors (e.g., mdm-2) in the progression of thyroid carcinomas is still poorly understood.  相似文献   
16.
This study examined the effects of anonymity, gender, and erotophilia on the quality of self-reports of socially sensitive health-related behaviors. A sample of 155 male and 203 female undergraduate students was randomly assigned to an anonymous and a confidential (i.e., nonanonymous) assessment condition. Gender, erotophilia, self-reports (of substance use, sexual behaviors, illegal activity), and perceived item threat were assessed by questionnaire. Data quality was strongly affected by experimental condition and gender. Thus, terminations were more frequent in the confidential condition and among women. In the confidential condition, women were significantly more likely to prefer not to respond to sensitive items compared to men. Both female gender and confidential condition were associated with lower frequency reports of sensitive health behaviors, and greater perceived threat of the assessment questions. Self-reported engagement in sensitive behaviors was positively related to both perceived question threat and erotophilia. Path analyses suggest that question threat mediates the effects of anonymity manipulations and gender on data quality (item refusal, termination), and that erotophilia mediates the effects of gender on incidence and frequency self-reports. The results indicate that anonymous assessments as well as male gender are associated with better data quality.  相似文献   
17.
SARS患者TGFβ1和PDGF-BB的动态监测及其临床意义   总被引:1,自引:0,他引:1  
目的动态监测严重急性呼吸综合征(SARS)患者血清转化生长因子β1(TGFβ1)和血小板衍生生长因子BB(PDGF-BB)水平的变化,以探讨细胞因子在SARS疾病中的作用。方法采用酶联免疫吸附试验 ,测定SARS患者早期、恢复期和随访时TGFβ1和PDGF -BB含量 ,并与急诊等一线未患SARS组及健康对照组比较 ,作描述性分析及方差分析。结果SARS患者早期组血清TGFβ1均值高于恢复期组和随访组 (P<0.05),SARS恢复期组、随访组TGFβ1均值均显著低于急诊等一线未患SARS组和健康对照组(P<0.01),其它组间两两比较均无显著性差异(P>0.05)。五组人群PDGF -BB均值水平总体比较无显著性差异(P>0.05)。结论TGFβ1可能与SARS患者机体调节免疫应答和免疫损伤有关 ,PDGF -BB与SARS的免疫损伤无关。  相似文献   
18.
Mutations in the gene encoding the Survival Motor Neuron (SMN) protein are responsible for autosomal recessive proximal spinal muscular atrophy (SMA). SMN orthologues have been identified in the nematode worm Caenorhabditis elegans and the yeast Schizosaccharomyces pombe but, to date, no human paralogues have been described. Here we describe identification and characterization of an SMN-related protein (SMNrp) gene that encodes a novel protein of 239 amino acids, which has recently been identified as a constituent of the spliceosome complex and designated SPF30. Significant similarity to the SMN protein is apparent only within a central region of SMNrp that represents a tudor domain. The SMNrp/SPF30 gene has been mapped to chromosome 10q23. It is differentially expressed, with abundant levels in skeletal muscle. An exclusively nuclear localization for SMNrp in cultured cells and muscle sections was revealed using GFP fusion constructs and thereafter confirmed with a polyclonal antibody raised against SMNrp. Overexpression of SMNrp as a fusion protein in HeLa cells in culture induced dose-dependent apoptosis with positive TUNEL staining. In addition to a possible role for this protein as a pro-apoptotic factor, SMN and its related protein share significant similarities in sequence and cellular function.   相似文献   
19.
20.
Adhesion formation is a major source of postoperative morbidity and mortality. In this study, the ability of a variety of lazaroid formulations [the antioxidant 21-aminosteroid PNU74006F (tirilazad) and the non-steroidal 2-methylaminochroman derivative PNU83,836E] to reduce i.p. adhesion formation in three rabbit models was examined. In initial studies, PNU83836E was administered via Alzet miniosmotic pump to the site of injury. In the sidewall and double uterine horn models, PNU83,836E was administered via Alzet miniosmotic pump for the entire postoperative interval. In the sidewall model, there was a dose- dependent reduction in the area of the sidewall injury that was involved in adhesions. In the double uterine horn model, PNU83,836E was administered via Alzet miniosmotic pump to the area of injury for 1, 2, 3 or 7 days. Administration for as little as 24 h after surgery significantly reduced the extent of adhesion formation and the reduction was increased if it was administered for longer. Further studies were conducted in which various lazaroid formulations were administered as a bolus at the end of surgery. In both the sidewall and double uterine horn models, administration of either PNU83,386E (in citrate buffer) or PNU74006F (in cyclodextrin or lipid emulsion vehicles) at the end of surgery reduced adhesion formation. Administration of a bolus of PNU74006F 10 min prior to initiation of surgery with or without additional treatment at the end of surgery further increased its efficacy in the reduction of adhesion formation. Administration of a minimum of 1.5 mg before and after surgery (3 mg total) was required for maximal efficacy. These studies demonstrate that pre- and postoperative administration of either a steroidal (PNU74006F) or non-steroidal (PNU83,836E) lazaroid intraperitoneally reduced the formation and reformation of postoperative adhesions in three animal models.   相似文献   
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