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11.
32例国产人工髋关节翻修手术的临床体会   总被引:5,自引:3,他引:5  
目的:探讨国产人工髋关节翻修原因。方法:回顾总结32例人工髋关节翻修中发现的问题,分析翻修原因。结果:32例中术前诊断松动16例,脱位4例,深部感染2例,白磨通3例,断柄2例,髋周及股部疼痛4例,股骨柄穿通皮质1例。26例取出假体顺利,6部部分骨长入珍珠面而取出假体困难。25例作全髋置换翻修,4例臼怀松动或位置不良致脱位仅翻修髋臼,1例股骨柄穿通皮质更换双动头,2例因深部感染严重而作单纯假体取出、清创术。全组病例经6个月-5年随访,Harris评分术前平均43分,术后平均81分,平均增加38分。结论:目前翻修病例仍以国产人工关节为主。翻修原因主要是:人工关节质量因素和手术技术因素。造成假体过早松动或种种其它并发症,最终失败。提示国产人工关节质量需改进,需相应配套器械,手术操作技术有待提高。  相似文献   
12.
BACKGROUND: To compare bone mineral density (BMD) in children and adolescents with celiac disease (CD) and control subjects and to evaluate diet adequacy and calcium metabolism in patients with CD. METHODS: Thirty patients with asymptomatic CD (17 children, 13 adolescents), on a gluten-free diet, and 23 healthy subjects were studied. BMD of the lumbar spine (dual energy x-ray absorptiometry) was performed on all patients and control subjects. In patients, food diaries for nine nonconsecutive days were obtained and analyzed. In patients, laboratory tests pertaining to calcium balance were obtained. RESULTS: The mean weight and height of the adolescents with CD were lower than those of control subjects (weight: 45.8 +/- 10.5 kg v 55.3 +/- 10.5 kg, P = 0.037; height: 153.0 +/- 11.0 cm v 167 +/- 12.0 cm, P = 0.007). The mean BMD in adolescents with CD was significantly lower than that of the control subjects (0.917 +/- 0.116 g/cm2 v 1.060 +/- 0.158 g/cm2, P = 0.015), whereas no significant difference was found between children with CD and control subjects (P = 0.595). A multiple-regression model shows that increases in BMD relative to height were lower in adolescents with CD than in control subjects. The proportion of adolescents who had started a gluten-free diet after 2 years of age was higher than that of children with CD (P < 0.001). High percentages of magnesium, calcium, and phosphorous deficiencies were present in CD patients' diets. The serum levels of ionized and total calcium and parathormone were normal. CONCLUSIONS: The BMD of adolescents with CD was lower than that of the control subjects, whereas no difference was found between the BMD of children with CD and that of control subjects.  相似文献   
13.

Background

The increased reports of ESBL dissemination from various centres in south western, Nigeria and the recent emergence of carbapenem resistant bacteria prompted the conception of this study.

Objectives

To demonstrate the relationship between high molecular weight plasmids and the expression of antibiotic multi-resistance including ESBL and carbapenemase.

Methods

We investigated 97 isolates of selected organisms consisting of 67 E. coli and 30 Klebseilla spp for the presence of plasmids expressing ESBL including carbapenem-hydrolysing enzymes. Beta-lactamase was determined using acidometric method, while ESBL and carbapenemase activity was determined using the double-disk diffusion test as well as the Modified Hodge test (MHT). Plasmid profiles of ESBL and carbapenemase positive isolates were determined according to standard protocols.

Results

An ESBL prevalence rate of 21.6% and carbapenem- resistance rate of 9.3% was recorded. Antibiotic susceptibility profile of ESBL isolates showed 100.0% resistance against Amoxicillin, Cotrimoxazole and Erythromycin. Moderate susceptibility was recorded against the Quinolone class of antibiotics; Meropenem remained the most active antibiotic against ESBL isolates with 62.5% against E. coli and 60% against K. pneumoniae. The plasmid profiles of our study isolates ranged from 11.8kbp to 35.5kbp.

Conclusion

Due to the relationship between high molecular weight plasmids and multi-drug resistance, we hereby recommend regular molecular surveillance of this form in our study setting.  相似文献   
14.
15.
Targeted gene disruption of murine CD7   总被引:2,自引:0,他引:2  
CD7 is a 40 kDa type I transmembrane glycoprotein member of the Ig superfamily. CD7 is a marker of mature human T cells and NK cells, and is expressed early in their development. Cross-linking CD7 positively modulates T cell and NK cell activity as measured by calcium fluxes, expression of adhesion molecules, cytokine secretion and proliferation. CD7 associates directly with phosphoinositol 3'-kinase, and CD7 ligation induces production of D-3 phosphoinositides and tyrosine phosphorylation. Severe combined immunodeficiency has been associated with a lack of lymphocyte surface CD7. The CD7 ligand is unknown. The murine CD7 homolog is encoded by a single gene on chromosome 11. In order to characterize the role of CD7 in lymphocyte development and function we have eliminated the CD7 gene by targeted disruption. CD7- deficient mice display normal histology of thymus and spleen, normal lymphocyte populations in primary and secondary lymphoid tissues, and normal serum Ig levels. Specific antibody responses after immunization with T-dependent and T-independent antigens are equivalent in wild-type and CD7 knockout mice. CD7-deficient lymphocytes respond normally to T cell mitogenic and allogeneic stimuli, and display normal NK cell cytotoxicity.   相似文献   
16.
Needle-localized breast biopsy: why do we fail?   总被引:10,自引:0,他引:10  
Jackman  RJ; Marzoni  FA  Jr 《Radiology》1997,204(3):677
  相似文献   
17.
18.
[摘 要] 目的 探讨肝癌患者血清来源的外泌体内miR-665与肝癌临床病理指标及预后的关系。方法 采用试剂盒方法提取患者血清内的外泌体并用透射电镜观察验证。然后利用RT-PCR方法检测30例肝癌患者和10例体检者血清来源的外泌体内miR-665的表达水平,进行对照研究,探讨临床病理指标和预后的关系。结果 血清提取的外泌体呈囊泡状,直径约30~150 nm。肝癌患者血清来源的外泌体miR-665较正常体检者表达水平明显升高,中位表达水平是对照组的8.3倍。外泌体miR-665高表达与患者肿瘤大小(>5 cm) (P=0.0042)、有包膜浸润(P=0.0197)以及临床TNM分期(III~IV期) (P=0.0276)成明显相关,与患者年龄、性别、HBsAg以及AFP水平未见明显相关性(P > 0.05),外泌体miR-665高表达组患者生存期较低表达组更短(P=0.036)。结论 肝癌患者血清中外泌体miR-665水平升高与肝癌进展相关,测定血清外泌体内miR-665的水平可能有助于肝癌的临床诊断和预后判断。  相似文献   
19.
Myelinated and nonmyelinated nerves: comparison of proton MR properties   总被引:1,自引:0,他引:1  
Jolesz  FA; Polak  JF; Adams  DF; Ruenzel  PW 《Radiology》1987,164(1):89-91
The magnetic resonance (MR) relaxation rates of protons were compared in the myelinated and nonmyelinated nerves of the garfish. The long, large olfactory nerve of the garfish, as an easily accessible source of nonmyelinated axons, is uniquely suited for such a comparison. The T1 and T2 measurements revealed distinct and consistent differences between nonmyelinated olfactory nerves and myelinated optic and oculomotor nerves. Comparisons between water content, lipid content, and relaxation rates indicated that the differences in MR properties represent complex differences in the distribution and physical environment of the constituent lipid and water protons.  相似文献   
20.
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