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971.
目的 探讨慢性丙型肝炎(CHC)患者外周血T细胞免疫功能与丙型肝炎病毒(HCV)复制及核心抗原(HCV-cAg)表达的关系.方法 采用流式细胞术、荧光定量PCR和ELISA对63例健康体检者(对照组)和85例CHC患者(CHC组)的外周血T淋巴细胞亚群、血清HCV-RNA和HCV-cAg进行测定.结果 CHC组总T细胞、T4细胞、T8细胞、双阴性细胞(DNT )、双阳性细胞(DPT )水平依次为(67 .37 ± 10 .43)% 、(37 .11 ± 10 .28)% 、(21 .63 ± 8 .87)% 、(7 .80 ± 4 .57)% 、(0 .20 ± 0 .29)% ,T4/T8比值为(2 .18 ± 1 .26 )% ,绝对水平依次为(0 .70 ± 0 .44 ) × 109/L、(0 .37 ± 0 .22 ) × 109/L、(0 .22 ± 0 .17 ) × 109/L、(0 .08 ± 0 .06 ) × 109/L和(0 .19 ± 0 .68)× 107/L ;CHC患者T8细胞水平显著减少(P<0 .01) ,致使T4/T8比值升高(P<0 .05);CHC患者总T细胞、T4细胞、T8细胞和DNT的绝对值均显著减少(P<0 .05);HCV-RNA和 HCV-cAg阳性时 ,T4细胞和DNT 水平显著升高(P<0 .05).结论 CHC患者 HCV复制表达时 ,患者 T细胞亚群存在明显异常 ,T细胞免疫功能低下或免疫耐受是CHC迁延难愈的重要原因. 相似文献
972.
目的:建立人结肠癌鸡胚移植模型,研究龙葵碱对其血管生成的影响。方法将鸡胚分为对照组和低剂量组、中剂量组、高剂量组(均n=10),将培养的人结肠癌细胞系HT‐29细胞株接种到鸡胚绒毛尿囊膜(CAM)上,通过立体显微镜、Image‐proplus6.0图像分析软件及免疫组织化学苏木精‐伊红(HE)染色法,观察移植瘤在CAM上血管生成的特点,及不同龙葵碱剂量对血管生成的影响。结果HT‐29细胞接种到CAM第3~5天,大量血管向瘤体集中,长入或跨越瘤体表面,肿瘤迅速生长。给药后第5天进行拍照,图像分析,定量计算血管新生面积明显低于对照组,且呈剂量依赖性,各组间差异有统计学意义(P<0.01)。免疫组织化学检测表明不同剂量龙葵碱的微血管密度明显低于对照组,与血管新生面积相一致;ki‐67抗原表达指数逐渐下降,实验组低于对照组,且各组间差异有统计学意义(P<0.01)。结论龙葵碱能明显抑制人结肠癌HT‐29细胞株诱导的血管生成,从而抑制肿瘤的生长,为抗肿瘤血管生成的治疗方面提供了重要依据。 相似文献
973.
974.
目的评价心脏矫治术期间使用血液回收(CS)技术处理回输术中出血及体外循环(CPB)管路余血对心脏外科患儿节约用血的意义和对临床结果的影响。方法根据术中是否使用CS,将100例在CPB下行先天性心脏病矫治术的患儿随机分为两组:洗血球组(CS组,n=50)和对照组(CON组,n=50)。记录两组患儿围术期红细胞比容(Hct),术后输入洗涤红细胞(RBCs)、血浆及血小板量,术后肝肾功能,术后24 h胸腔引流量,升压药使用时间和机械通气时间、ICU时间和住院时间,并进行统计学分析。结果两组患儿均痊愈出院。术后输入库血量及术后输血率CS组均明显低于CON组(P<0.05)。术后升压药使用时间CS组明显低于CON组(P<0.05)。两组患儿其余指标及术后恢复情况无明显差异(P>0.05)。结论对先天性心脏病婴幼儿手术期间使用CS处理术中出血和CPB管路余血可以明显减少术后输血量以及输血患儿的比率,达到节约用血的目的。 相似文献
975.
Dong Wang Lichun An Jiangke Tian Tengfei Yu Xia Xie Yuejuan Gao Yanfen Zang Yanyan Tao Yanqing Liu Ying Jin 《The American journal of emergency medicine》2018,36(9):1627-1630
Background
Real-time ultrasound elastography (RTE) is used to examine liver fibrosis and benign and malignant lesions, but its use for the diagnosis of liver trauma has not been examined. The purpose of this study was to examine the use of RTE for the evaluation of differential penetrating liver trauma in a rabbit model.Material and methods
Eighty New Zealand rabbits were divided into 2 groups. In one group, a single incision (type “-” lesion) was made, and in the other group a hash mark incision (type “#” lesion) was made (about 0.5 cm in depth; 1.0–2.0 cm in length). RTE was performed at 10, 30, and 60 min after injury.Results
There were no differences in mean RTE scores between the 2 types of lesions at 10 and 30 min. However, the mean values for the 2 types of lesions increased from 10 min to 60 min (type ‘-’ lesion: 0.88 ± 0.32 to 2.06 ± 0.88; type ‘#’ lesion: 0.89 ± 0.34 to 2.63 ± 1.16). At 60 min, the mean elasticity score in the type ‘#’ lesion group was significantly higher than in the type ‘-’ lesion group (P < .001). Strain ratios were not different between the groups at each time point, but in each group the values decreased from the 10 min time point to the 60 min time point (P-value for the trends, <.001).Conclusions
RTE may be able to distinguish mild or severe penetrating liver trauma at 60 min or more after injury. 相似文献976.
Objective: To examine the psychometric properties of the International Classification of Functioning, Disability and Health (ICF) set for spinal cord injury nursing (ICF-SCIN) using Rasch analysis.Methods: A total of 140 spinal cord injury patients were recruited between December 2013 and March 2014 through convenience sampling. Nurses used the components body functions (BF), body structures (BS), and activities and participation (AP) of the ICF-SCIN to rate the patients’ functioning. Rasch analysis was performed using RUMM 2030 software.Results: In each component, categories were rescored from 01234 to 01112 because of reversed thresholds. Nine testlets were created to overcome local dependency. Four categories which fit to the Rasch model poorly were deleted. After modification, the components BF, BS, and AP showed good fit to the Rasch model with a Bonferroni-adjusted significant level (χ2?=?86.29, p?=?0.006; χ2?=?22.44, p?=?0.130; χ2?=?39.92, p?= 0.159). The person separation indices (PSIs) for the three components were 0.80, 0.54, and 0.97, respectively. No differential item functioning (DIF) was detected across age, gender, or educational level.Conclusions: The fit properties of the ICF set were satisfactory after modifications. The ICF-SCIN has the potential as a nursing assessment instrument for measuring the functioning of patients with spinal cord injury.
- Implications for rehabilitation
The International Classification of Functioning, Disability and Health (ICF) set for spinal cord injury nursing contains a group of categories which can reflect the functioning of spinal cord injury patients from the perspective of nurses.
The components body functions (BF), body structures (BS), and activities and participation (AP) of the ICF set for spinal cord injury achieved the fit to the Rasch model through rescoring, generating testlets, and deleting categories with poor fit.
The ICF set for spinal cord injury nursing (ICF-SCIN) has the potential to be used as a clinical nursing assessment tool in measuring the functioning of patients with spinal cord injury.
977.
978.
目的 :检测3%苦参碱水剂的致突变作用。方法 :应用鼠伤寒沙门氏菌回复突变试验(Ames试验),小鼠骨髓多染红细胞微核试验,哺乳动物细胞基因(TK位点)突变试验,哺乳动物细胞染色体畸变试验进行3%苦参碱水剂的致突变作用研究。结果 :Ames试验中,3%苦参碱水剂各剂量组回变菌落数均未超过溶剂对照组回变菌落数的2倍;与相应对照组比较,各剂量组3%苦参碱水剂小鼠骨髓多染红细胞微核率未明显增加,未见哺乳动物细胞基因(TK位点)的致突变效应及对哺乳动物细胞染色体畸变作用,差异均无显著性。结论 :在本实验条件下,3%苦参碱水剂未见明显致突变作用。 相似文献
979.
Yiran Guo Ivan Prokudin Cong Yu Jinlong Liang Yi Xie Maree Flaherty 《Ophthalmic genetics》2015,36(4):333-338
Background: Leber congenital amaurosis (LCA) is a severe form of retinal dystrophy with marked underlying genetic heterogeneity. Until recently, allele-specific assays and Sanger sequencing of targeted segments were the only available approaches for attempted genetic diagnosis in this condition. A broader next-generation sequencing (NGS) strategy, such as whole exome sequencing, provides an improved molecular genetic diagnostic capacity for patients with these conditions.Materials and Methods: In a child with LCA, an allele-specific assay analyzing 135 known LCA-causing variations, followed by targeted segment sequencing of 61 regions in 14 causative genes was performed. Subsequently, exome sequencing was undertaken in the proband, unaffected consanguineous parents and two unaffected siblings. Bioinformatic analysis used two independent pipelines, BWA-GATK and SOAP, followed by Annovar and SnpEff to annotate the variants.Results: No disease-causing variants were found using the allele-specific or targeted segment Sanger sequencing assays. Analysis of variants in the exome sequence data revealed a novel homozygous nonsense mutation (c.1081C?>?T, p.Arg361*) in TULP1, a gene with roles in photoreceptor function where mutations were previously shown to cause LCA and retinitis pigmentosa. The identified homozygous variant was the top candidate using both bioinformatic pipelines.Conclusions: This study highlights the value of the broad sequencing strategy of exome sequencing for disease gene identification in LCA, over other existing methods. NGS is particularly beneficial in LCA where there are a large number of causative disease genes, few distinguishing clinical features for precise candidate disease gene selection, and few mutation hotspots in any of the known disease genes. 相似文献
980.
目的:观察bevacizumab对人Tenon囊成纤维细胞迁移能力的影响,探讨青光眼术后滤过泡瘢痕化的对策。方法:采用从陕西省人民医院中心实验室细胞库中取出冻存的人Tenon囊成纤维细胞,采用细胞复苏法,遵循无菌原则,进行常规培养。创伤划痕试验:待细胞融合度达到80%时在单层细胞表面划出一条无细胞的刮除带,空白对照组加入不含血清的DMEM培养液,bevacizumab处理组加入 bevacizumab 浓度为1 mg/mL 不含血清的DMEM培养液,分时段(0,24,48,72h)观察并测量划痕宽度。结果:人Tenon囊成纤维传代细胞显微镜下观察呈长梭形,细胞核位于细胞的中部,核较大,胞浆丰富,生长时呈漩涡状排列走形,增殖能力强,符合成纤维细胞的一般形态。冻存和复苏后细胞的形态结构和生物学特点维持不变。细胞划痕试验显示:0h时,两组细胞划痕初始宽度相等;24 h 时两组细胞迁移距离基本一致;48 h 时bevacizumab处理组细胞迁移距离明显小于空白对照组;72 h时空白对照组划痕基本愈合, bevacizumab处理组细胞迁移距离较48 h无明显变化,且细胞死亡数目较多。结论:利用细胞复苏法可成功培养形态结构和生物学特性稳定的传代人Tenon囊成纤维细胞,为实验研究奠定细胞学基础。成纤维细胞本身具有较强的迁移能力,外源性bevacizumab作用可以明显抑制细胞的迁移,作用时间过长时,会造成细胞的过多死亡。抗新生血管药物对成纤维细胞的迁徙具有一定的抑制作用,未来很有可能成为眼科临床抗击青光眼术后滤过泡瘢痕化的重要手段。 相似文献