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141.
Y. F. Huang W. Wang J. Y. Han X. W. Wu S. T. Zhang C. J. Liu Q. G. Hu P. Xiong R. M. J. Hamvas N. Wood F. L. Gong A. H. Bittles 《International journal of immunogenetics》2003,30(2):121-124
Mannose‐binding lectin (MBL) is an important complement‐activating protein of the human immune system. As a result of one of three structural gene mutations in exon 1 (variants B, C and D) and/or the presence of a low‐efficiency promoter polymorphism, MBL deficiency may be associated with increased susceptibility to infectious diseases and to autoimmune disorders, including systemic lupus erythematosus (SLE). Using a combined approach of heteroduplex generator and polymerase chain reaction, a systematic search for mutations in exon 1 and the promoter region of the MBL gene was performed in a Chinese study population comprising 41 SLE patients and 111 healthy controls. Two alleles, a wild‐type allele A and a variant allele B (a previously reported mutation of GGC to GAC at codon 54), were identified in MBL exon 1. The frequency of the B allele (0.15) was higher in the SLE patients than in the healthy controls (0.09), but the difference did not attain statistical significance (P > 0.05). However, for two polymorphisms at positions ?550 and ?221 in the promoter region, the frequency of the low‐MBL‐producing haplotype (LX) in the patients (0.2073) was significantly higher than that in the controls (0.0855) (P = 0.003, relative risk = 2.79). Our results suggest that the LX haplotype represents a strong risk factor among Chinese SLE patients. Although of lesser importance, the MBL B allele also may be a risk component in the developing process of SLE in Chinese patients. 相似文献
142.
采用含造影剂及显色剂的填充剂对成年SD大鼠动脉血管系统进行灌注,并借助数字X射线成像设备对灌注效果进行实时监测,通过断层解剖成像系统获取切削间距为100 μm的二维断面解剖数据集(图像分辨率为4917×3446×24 bit,共1 464张),最后利用Visual C 结合可视化工具包编程实现数据集的动脉分割及三维可视化,得到数字化SD大鼠动脉血管系统的三维模型.该模型能提供大鼠动脉血管系统的空间结构信息,为实验大鼠血管系统的研究提供了更为准确可靠的形态学参考. 相似文献
143.
七年制医学生消化内科临床见习带教体会 总被引:1,自引:1,他引:1
七年制医学生基础知识扎实、自学能力强,但临床分析和解决问题的实际工作能力欠缺,而临床见习是医学生理论联系实际的纽带和桥梁。因此,努力提高临床见习的带教效果,对于医学生理解、巩固所学基础知识,为临床实习奠定良好的实践基础至关重要。现结合我科多年带教七年制学生见习的具体情况,探讨如何提高七年制医学生临床见习的带教效果。1传统消化内科见习带教中的困难和缺陷消化内科理论课学时多、专业性强,学习内容多、概念抽象,使学生理解较困难。过去见习带教中大部分时间以教师讲课为主,学生多处于被动地位,部分学生出现厌烦、兴趣不浓… 相似文献
144.
Erica di Martino Laura J Hardie Christopher P Wild Yun Y Gong Joanna R Olliver Martin D Gough Nigel C Bird 《Genetics in medicine》2007,9(6):341-347
PURPOSE: The role of genetic susceptibility to esophageal adenocarcinoma and its precursor lesion Barrett esophagus has not been fully elucidated. This study investigated the effect of polymorphisms in the manganese superoxide dismutase (MnSOD) and NAD(P)H:quinone oxidoreductase 1 (NQO1) genes in modulating the risk of developing Barrett esophagus or esophageal adenocarcinoma. METHODS: A total of 584 patients (146 esophagitis, 200 Barrett esophagus, 144 esophageal adenocarcinoma, and 94 controls) were genotyped for the MnSOD C14T and NQO1 C609T polymorphisms using polymerase chain reaction and restriction fragment length polymorphism analysis. RESULTS: The NQO1 TT genotype was less common in Barrett esophagus (2.0%) and esophageal adenocarcinoma (1.4%) patients, compared with both esophagitis patients (7.6%) and controls (5.4%). After adjustment for sex, age, body mass index, reflux symptoms, and smoking status, patients with the homozygous TT genotype had a 4.5-fold decreased risk of developing Barrett esophagus (odds ratio = 0.22, 95% confidence interval = 0.07-0.76, P = 0.01) and a 6.2-fold decreased risk of esophageal adenocarcinoma (odds ratio = 0.16, 95% confidence intervals = 0.03-0.94, P = 0.04) compared with individuals with the TC and CC genotypes. No significant differences between groups were observed for the MnSOD polymorphism (P = 0.289). CONCLUSIONS: Overall, the results of this study suggest that the NQO1 TT genotype may offer protection from reflux complications such as Barrett esophagus and esophageal adenocarcinoma. 相似文献
145.
Diagnostic impact of core-needle biopsy on fine-needle aspiration of non-Hodgkin lymphoma 总被引:1,自引:0,他引:1
Gong JZ Snyder MJ Lagoo AS Vollmer RT Dash RR Madden JF Buckley PJ Jones CK 《Diagnostic cytopathology》2004,31(1):23-30
We retrospectively reviewed 74 fine-needle aspiration (FNA) cases of presumptive non-Hodgkin lymphoma (NHL). All the cases had cytology and core-needle biopsy and 53 cases had concurrent flow cytometric analysis. FNA (cytology and flow cytometry) and core-needle biopsy were evaluated independently. FNA was diagnostic of diffuse large B-cell lymphoma (DLBL) in 25% (13/53) of cases and small B-cell NHL in 15% (8/53) of cases, whereas core-needle biopsy was diagnostic of DLBL in 37% (27/74) of cases and small B-cell NHL in 8% (6/74) of cases. Subclassification of small B-cell NHL was reached in 3/6 cases by core-needle biopsy. Insufficient cases were observed in both FNA (47%; 25/53) and core-needle biopsy (28%; 21/74) groups. With the combination of FNA and core-needle biopsy, diagnostic cases of DLBL increased to 43% (32/74) and insufficient samples were reduced to 16% (12/74). There was no clear advantage in the diagnosis and classification of small B-cell NHL by adding core-needle biopsy to FNA (14%; 10/74). We conclude that core-needle biopsy is a useful adjunct to FNA in the diagnosis of DLBL and shall be encouraged. In small B-cell NHL, core-needle biopsy does not add to the diagnostic ability of FNA. Cases insufficient for diagnosis may be seen in both core-needle biopsy and FNA. A combined approach reduces the number of insufficient cases and is recommended in routine FNA practice. 相似文献
146.
目的 构建趋化因子受体CCR5反义RNA真核表达载体并获取重组假病毒颗粒以用于抗HIV-1研究,方法 用RT-PCR法从健康人外周血单个核细胞(PBMCs)中获得趋化因子受体CCR5翻译起始区的基因片段,并以正、反两个方面定向插入到真核表达载体pLXSN上,重组载体用脂质体转染剂(lipofectAMINE)转染PA317包装细胞,抗-G418克隆的细胞上清经逆转录后用荧光定量PCR(FQ-PCR)测定假病毒滴度,进一步感染NIH/3T3细胞。结果 CCR5正、反义RNA的真核表达载体。经PA317细胞包装形成的假病毒颗粒已成功地感染NIH/3T3细胞,目的基因在该细胞中得到整合与表达。结论 从PBMCs中获得的趋化因子受体CCR5基因片段通过逆转录病毒载体可转移至真核细胞中并得到表达,为进一步研究CCR5反义RNA的抗HIV-1作用奠定了基础。 相似文献
147.
148.
以三级公立医院绩效考核及院长绩效考核为指导,结合医院实际情况,构建医院核心工作指标体系。运用目标与关键成果法管理理念,从医院的发展目标和核心问题出发,通过流程优化、任务分解、全员参与,聚焦有挑战性的目标,从而实现管理模式转变。认为核心工作指标体系可赋能医院绩效管理,充分发挥绩效考核在医院管理中的“指挥棒”作用。 相似文献
149.
Priyanka Sharma Guojun Wu Deeptha Kumaraswamy Natalie Burchat Hong Ye Yongjia Gong Liping Zhao Yan Y. Lam Harini Sampath 《Nutrients》2021,13(2)
7,8-Dihydroxyflavone (DHF) is a naturally occurring flavonoid that has been reported to protect against a variety of pathologies. Chronic administration of DHF prevents high-fat diet (HFD)-induced obesity in female, but not male, mice. However, the mechanisms underlying this sexual dimorphism have not been elucidated. We have discovered that oral DHF supplementation significantly attenuates fat mass, hepatic lipid accumulation, and adipose tissue inflammation in female mice. In contrast, male mice were not protected from adiposity, and had a paradoxical worsening of hepatic lipid accumulation and adipose tissue inflammation upon DHF supplementation. Consistent with these sexually dimorphic effects on body weight and metabolic health, 7,8-DHF induced early and stable remodeling of the female intestinal microbiome. DHF supplementation significantly increased gut microbial diversity, and suppressed potentially detrimental bacteria, particularly Desulfovibrionaceae, which are pro-inflammatory and positively associated with obesity and inflammation. Changes in the female gut microbiome preceded alterations in body weights, and in silico analyses indicated that these early microbial changes were highly predictive of subsequent weight gain in female mice. While some alterations in the intestinal microbiome were also observed in male DHF-supplemented mice, these changes were distinct from those in females and, importantly, were not predictive of subsequent body weight changes in male animals. The temporality of microbial changes preceding alterations in body weight in female mice suggests a role for the gut microbiome in mediating the sexually dimorphic effects of DHF on body weight. Given the significant clinical interest in this flavonoid across a wide range of pathologies, further elucidation of these sexually dimorphic effects will aid the development of effective clinical therapies. 相似文献
150.
目的探讨剖宫产术后阴道分娩(VBAC)产妇的母儿结局。 方法选择2016年1月1日至2019年12月31日,四川大学华西第二医院收治的VBAC足月妊娠产妇397例为研究对象,纳入研究组。按照1∶1比例,采用随机数字表法随机抽取同期于本院足月经阴道分娩的非瘢痕子宫产妇397例,作为对照,纳入对照组。观察2组产妇年龄、身高、人体质量指数(BMI)、本次分娩距前次分娩间隔时间、分娩时孕龄,第一、第二、第三产程时间,术中出血量、产后出血(PPH)量(2 h)、PPH率、严重PPH率,以及新生儿出生体重与窒息发生率等指标,并采用成组t检验、Wilcoxon秩和检验、χ2检验和Fisher确切概率法对上述指标进行统计学比较。对2016—2019年本院产妇分娩情况进行分析。2组产妇年龄、身高、BMI、分娩时孕龄等一般临床资料比较,差异均无统计学意义(P>0.05)。本研究遵循的程序符合2013年新修订的《世界医学协会赫尔辛基宣言》要求。 结果①2016—2019年,本院剖宫产术分娩率为58.45%~62.37%,剖宫产术后瘢痕子宫(SUAC)患者再次妊娠的剖宫产术分娩率为93.06%~95.83%,平均为94.60%(10 942/11 567),非SUAC患者的剖宫产术分娩率为50.27%(18 586/36 972)。瘢痕子宫患者为13 963例(28.77%),2017年瘢痕子宫患者所占比例最高,为33.74%(3 361/9 961),此后呈下降趋势。②研究组产妇第一、第二产程时间及术中出血量、PPH量(2 h)、PPH率分别为363 min(212~450 min)、46 min(22~60 min)、312 mL(200~350 mL)、348 mL(230~380 mL)、10.8%(43/397),均显著长于、大于、高于对照组的294 min(180~380 min)、15 min(7~20 min)、231 mL(150~280 mL)、264 mL(180~310 mL)、4.3%(17/397),研究组新生儿出生体重为(3 216±359) g,则显著低于对照组的(3 369±369) g,并且差异均有统计学意义(Z=4.797、16.065、8.028、8.122,χ2=12.188,t=-17.013,均为P<0.001)。③SUAC患者再次妊娠的子宫破裂发生率为1.73/10 000(2/11 567),占VBAC者的0.32%(2/625)。 结论VBAC是可行的,子宫破裂发生率低,但是其PPH风险增加。临床对于此类产妇,产程中应做好监护,积极预防PPH。 相似文献