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81.
We evaluated PyroMark Q24 (QIAGEN) pyrosequencing as a method for the identification of mycobacteria, with potential application in clinical practice. Sequence data from the hypervariable region A of the 16S rRNA gene (43 and 35 bp sequences) were obtained using PyroMark Q24, and a similarity search was performed automatically with PyroMark IdentiFire software. Of the 148 mycobacterial type strains tested, 138 (93.2%) were accurately identified to single or clade species level, including complex level. From the remaining 10 strains, 3 (Mycobacterium gilvum, Mycobacterium goodi, and Mycobacterium thermoresistible) showed poor sequencing quality of homopolymers. For 6 other strains (Mycobacterium cosmeticum, Mycobacterium flavescens, Mycobacterium pallens, Mycobacterium hodleri, Mycobacterium xenopi, and Mycobacterium crocinum), the sequences were unreadable from the middle, and Sanger sequencing indicated biallelic site. Finally, a 40 bp sequence for Mycobacterium gordonae could not be obtained despite repeated attempts. PyroMark Q24 provided accurate identification of multiple mycobacterial strains isolated from common clinical settings, but additional gene sequencing is required to distinguish species identified as a group or complex.  相似文献   
82.
目的:观察消渴保肾汤联合贝前列素钠治疗糖尿病肾病的临床疗效。方法:90例糖尿病肾病患者随机分为联合治疗组、贝前列素钠组、消渴保肾汤组,每组30例。贝前列素钠组采用贝前列素钠治疗;消渴保肾汤组采用消渴保肾汤治疗;联合治疗组采用贝前列素钠与消渴保肾汤联合治疗,3组治疗周期均为20周。比较治疗前后各组的24小时尿微量白蛋白、血清 C 反应蛋白(C-reactive protein,CRP)、肿瘤坏死因子-α(tumour necrosis factor-α,TNF-α)、血糖、糖化血红蛋白、血肌酐水平。结果:治疗前,3组之间的24小时尿微量白蛋白、血清 CRP 与 TNF-α比较,差异无统计学意义(P >0.05);与治疗前比较,3组治疗后的24小时尿微量白蛋白、血清 CRP 与 TNF-α水平均显著降低,差异有统计学意义(P <0.05);联合治疗组的24小时尿微量白蛋白、血清 CRP 与 TNF-α水平显著低于贝前列素钠组及消渴保肾汤组,差异有统计学意义(P <0.05)。治疗后,3组患者的血糖水平、糖化血红蛋白和血肌酐水平比较,差异无统计学意义(P >0.05)。结论:消渴保肾汤联合贝前列素钠治疗糖尿病肾病疗效较好,能够降低24小时尿微量白蛋白、血清 CRP 与 TNF-α水平,缓解糖尿病肾病患者微炎症反应。  相似文献   
83.
When analyzing many health‐related quality‐of‐life (HRQoL) outcomes, statistical inference is often based on the summary score formed by combining the individual domains of the HRQoL profile into a single measure. Through a series of Monte Carlo simulations, this paper illustrates that reliance solely on the summary score may lead to biased estimates of incremental effects, and I propose a novel two‐stage approach that allows for unbiased estimation of incremental effects. The proposed methodology essentially reverses the order of the analysis, from one of ‘aggregate, then estimate’ to one of ‘estimate, then aggregate’. Compared to relying solely on the summary score, the approach also offers a more patient‐centered interpretation of results by estimating regression coefficients and incremental effects in each of the HRQoL domains, while still providing estimated effects in terms of the overall summary score. I provide an application to the estimation of incremental effects of demographic and clinical variables on HRQoL following surgical treatment for adult scoliosis and spinal deformity. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
84.
目的对即时性图像法应用于学龄前儿童膳食调查进行效果评价。方法招募60位幼儿园儿童及其家长,为儿童提供食物原料经严格称重后烹制的午餐。进餐前家长从三个角度对食物进行拍摄,同样方法拍摄剩余食物,并将图像文件发送至固定邮箱,次日接受针对儿童的24h膳食回顾调查,膳食估量小组成员对图片中的食物进行估重。得到称量数据、图像法数据和24h回顾法数据,归类汇总三组数据并进行营养计算。结果与24h回顾法数据相比,除水果和带鱼外,图像法数据与称重数据的相关性更好。除畜禽肉类和带鱼外,图像法的数据与称重法更接近。基于图像法数据计算的能量与各营养素的摄入量数据,与称重数据的计算结果更接近。结论与24h回顾法相比,用即时性图像法膳食调查技术对学龄前儿童进行膳食调查,可获得与实际重量更接近的食物消费量数据。  相似文献   
85.
T cell-mediated suppression of haematopoiesis is believed to play an important role in the pathophysiology of aplastic anaemia (AA) and in the pancytopenia of some myelodysplastic syndromes (MDS). Natural-killer T (NKT) cells belong to a unique lymphocyte subset that expresses an invariant T-cell receptor (TCR), consisting of Valpha24JalphaQ, and common NK cell surface markers. NKT cells have been hypothesized to play a role in immune regulation, and many human autoimmune conditions are associated with NKT cell deficiency. Here we investigate the role of NKT cells in AA and MDS patients. Flow cytometry demonstrated that NKT cells, unlike other T-lymphocyte subpopulations, were disproportionally decreased in AA and MDS marrow. When we compared variability within the CDR3 region of Valpha24 in CD4-CD8- T cells derived from AA and healthy individuals, the CDR3 size of Valpha24 cells showed a polyclonal distribution in AA patients, while in control subjects a typical oligoclonal or monoclonal pattern was found. Southern blot and sequence analysis of Valpha24 polymerase chain reaction products revealed that the NKT cell-specific JalphaQ region was predominant in control subjects, whereas it was not, or only very weakly, detected in AA and MDS patients. These results show that NKT cells are profoundly decreased in AA and MDS, and their deficiency may, as in other human autoimmune diseases, play a role in the local immune dysregulation in AA and MDS.  相似文献   
86.
Human Valpha24+ natural killer T (NKT) cells correspond to mouse Valpha14+ NKT cells, both cell types use an invariant T-cell receptor-alpha chain and are activated by glycolipids in a CD1d-dependent manner. Mouse Valpha14+ NKT cells have been reported to have an antitumour effect in vivo. Human Valpha24+ NKT cells can kill a proportion of tumour cells in a CD1d-dependent manner in vitro. We report here that many human leukaemic T-cell lines express CD1d and can be directly killed by Valpha24+ NKT cells. This killing activity was enhanced in the presence of alpha-galactosylceramide (alpha-GalCer), a ligand of Valpha24+ NKT cells. Moreover, primary leukaemic T cells from five of eight T-cell acute lymphoblastic leukaemia (T-ALL) patients expressed CD1d and were good targets of Valpha24+ NKT cells. This cytotoxicity was increased in the presence of alpha-GalCer. Our results suggest that T-ALL is a good candidate for Valpha24+ NKT-cell-based immuno-cell therapy.  相似文献   
87.
Esophageal motor abnormalities are currently categorized into separate entities based on standard manometry. The clinical significance of these categories is controversial. We evaluated whether ambulatory 24-h esophageal motility monitoring improves the assessment of patients thought to have a primary esophageal motor disorder. Standard and ambulatory 24-h esophageal motility records of 30 healthy volunteers and 136 symptomatic patients were compared. Regression analysis was used to identify parameters that relate to the presence of nonobstructive dysphagia. Prolonged ambulatory esophageal monitoring showed a marked circadian variation in the esophageal motor pattern and significant discrepancies to the findings on standard manometry in 47% of the 136 patients. Discrepancies were particularly frequent in patients categorized on standard manometry as having a 'nutcracker esophagus' or a nonspecific motor disorder. Of all data obtained, the prevalence of 'effective contractions', i.e. peristaltic contractions with an amplitude > 30 mmHg, during meal periods provided the best correlation with the presence of nonobstructive dysphagia. Of the 78 patients with nonobstructive dysphagia 71 (92%) had less than 50% of 'effective contractions' during meals. In five patients who had frequent simultaneous wave forms and less than 70%'effective contractions' during meals a long myotomy markedly reduced the severity of dysphagia. The 'efficacy' of esophageal contractions during meals best relates to patients' symptoms and allows expression of esophageal body dysfunction on a linear scale. This obviates the need for the current categories of esophageal motor disorders, permits an objective assessment of medical therapy and may improve the identification of patients that benefit from a surgical myotomy of the esophageal body.  相似文献   
88.
The study investigated the effect of either nocturnal acid suppression by the H2 antagonist nizatidine 300 mg at night or prolonged acid suppression by the proton-pump inhibitor omeprazole 20 mg in the morning, during four weeks, on intragastric pH profile, occurrence of bacterial growth in gastric fluid and biopsies, and healing rate in 23 patients with an acute duodenal ulcer. The endoscopic healing rate did not differ significantly between the two treatment modalities. The 24-hr acid secretion was significantly more reduced by omeprazole than nizatidine (P<0.002). After treatment by nizatidine and omeprazole, respectively, median 24-hr intragastric pH increased from 1.5 to 1.8 (P<0.01) and from 1.5 to 6.1 (P<0.01), respectively. Nighttime acid inhibition did not differ significantly. The difference in gastric bacterial colonization after either omeprazole or nizatidine did not reach significance. However, median 24-hr pH and the fraction of the day with pH<3 and pH<4 were significantly correlated to bacterial colonization of the gastric fluid (P<0.05).This study was supported by Eli Lilly Nederland B.V.  相似文献   
89.
90.
曹丽  孙燕  张静  曹雷 《现代药物与临床》2020,43(9):1836-1839
目的 研究羟氯喹联合利妥昔单抗治疗系统性红斑狼疮的临床疗效。方法 选择2017年1月—2019年12月榆林市第二医院的系统性红斑狼疮患者71例作为研究对象。用抽签法随机将患者分为对照组(36例)和观察组(35例)。对照组iv利妥昔单抗注射液,100 mg/次,1次/周。观察组在对照组基础上口服硫酸羟氯喹片,0.4 g/次,2次/d。两组均治疗4周。观察两组患者的临床疗效,同时比较两组治疗前后的系统性红斑狼疮疾病活动指数(SLEDAI)评分、24 h尿蛋白、血肌酐、血清白蛋白和炎性因子水平。结果 治疗后,观察组的有效率为91.43%,明显高于对照组的69.44(P<0.05)。治疗后,两组的SLEDAI评分、血肌酐及24 h尿蛋白水平明显降低,血清白蛋白水平明显升高(P<0.05);且观察组的SLEDAI评分、血肌酐及24 h尿蛋白水平明显低于对照组,血清白蛋白水平明显高于对照组(P<0.05)。治疗后,两组血清白细胞介素(IL)-4、IL-17和单核细胞趋化蛋白-4(MCP-4)水平明显降低(P<0.05),且观察组的血清IL-4、IL-17和MCP-4水平明显低于对照组(P<0.05)。结论 羟氯喹联合利妥昔单抗能改善系统性红斑狼疮患者的免疫功能,降低血清IL-4、IL-17和MCP-4水平,具有一定的临床推广应用价值。  相似文献   
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