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621.
目的:胰岛素样生长因子(insulin-likegrowthfactor,IGF)-I与IGF-Ⅱ在代谢和生长调节中都发挥着重要的作用。先前我们报道过在血糖正常的正常体重个体中,低浓度IGF-Ⅱ预示着将来体重的增加。我们接着又研究了在2型糖尿病的情况下这一关系是否仍旧成立。方法:在为期5年的随访中,我们对224例2型糖尿病患者中基线时IGF-Ⅱ水平与体重增加风险(>2.0kg)之间的关系作了评估。结果:在随访期间有90位受试者(40.2%)体重增加高于2.0kg。对于基线时的受试者[体重指数(bodymassindex)<26],在体重增加高于2.0kg受试者的平均IGF-Ⅱ水平要显著低于体重…  相似文献   
622.
AIM: To assess incidence of hyperhomocysteinemia (HHC) in patients with chronic myeloproliferative diseases (CMPD) and to analyse possible correlation between an elevated concentration of plasma homocystein (HC) and thrombotic complications. MATERIAL AND METHODS: The trial enrolled 61 patients: 39 CMPD patients with thrombotic complications and free of them, 22 nonhematological patients with thrombosis. The control group consisted of 40 healthy donors. The examination protocol included determination with standard methods of HC plasma concentration, platelet and plasma components of hemostasis, mutation of factor V Leiden gene, prothrombin and methylenetetrahydrofolate reductase (MTHFR). RESULTS: Mean HC concentration in the serum in CMPD patients was 19 +/- 1.7 mcmol/l which appeared higher than in healthy donors (12 +/- 1.3 mcmol/l). The highest HC was in patients with subleukemic myelosis (SLM)--23 +/- 2.3 mcmol). No difference in HC concentration in plasma was observed in CMPD carriers of homo- or heteroxygous mutation of C667T gene or CMPD patients without the mutation. In CMPD content of factor VIII was higher in HHC than in normal HC (222 +/- 26.5 and 116 +/- 20%, respectively, p = 0.002). For von Willebrand factor 202 +/- 15.6 and 120 +/- 14.6%, respectively (p < 0.003). HC reduction in response to vitamin therapy was the greater the higher its initial level was. CONCLUSION: There is correlation between HHC and thrombosis in CMPD patients. HC concentration may depend on the proliferative stage of CMPD. As HC is a significant independent factor of thrombotic complications risk, it is necessary to detect and treat HHC.  相似文献   
623.
Sensitive methods for assessment of the hemostatic state are essential for providing adequate therapy to patients with β-thalassemia. The present study was designed to monitor the changes in the hemostatic state of a patient with β-thalassemia at the primary stage and under heparin treatment following splenectomy. The hemostatic state of the patient was assessed using conventional tests (activated partial thromboplastin time, prothrombin index, thrombin time), fibrinogen and D-dimer assays, thromboelastography (TEG), thrombin generation test, and a novel thrombodynamics clot growth assay. Thrombodynamics parameters indicated the hypercoagulation state on the primary evaluation which progressed after splenectomy: stationary clot growth velocity increased from 32 to 38 μm/min (normal range 20–30 μm/min). Hypercoagulation state was confirmed by Doppler echocardiography, which detected portal vein thrombosis on day 23 after surgery. The results of the other tests’ parameters were in the normal ranges before splenectomy. The TEG parameters were sensitive to low molecular weight heparin (LMWH) injections; but the values were close to the normal ranges before and after injections. The thrombodynamics assay demonstrated a high sensitivity to LMWH injections, and registered a decrease of the hypercoagulability in the course of therapy (P < 0.05). TGT was not performed during LMWH therapy. This clinical case demonstrates the potential of the thrombodynamics assay to serve as a sensitive method for coagulation system monitoring and prediction of prothrombotic tendencies in patients with hemolytic anemias.  相似文献   
624.

Background  

Methamphetamine (MA) use continues to be a major public health concern in many urban settings. We sought to assess potential relationships between MA use and individual, social, and structural HIV vulnerabilities among sexual minority (lesbian, gay, bisexual or transgendered) drug users.  相似文献   
625.
INTRODUCTION: the deadly threat of systemic infections with coagulase negative Staphylococcus lugdunensis despite an appropriate antibiotic therapy has only recently been recognized. The predominant infectious focus observed so far is left-sided native heart valve endocarditis, but bone and soft tissue infections, septicaemia and vascular catheter-related bloodstream infections have also been reported. We present a patient with a fatal Staphylococcus lugdunensis septicaemia following zoster bacterial superinfection of the pelvic region. case presentation: a 71-year old male diagnosed with IgG kappa plasmocytoma presented with a conspicuous weight loss, a hypercalcaemic crisis and acute renal failure. After initiation of haemodialysis treatment his condition improved rapidly. However, he developed a varicella-zoster virus infection of the twelfth thoracic dermatome requiring intravenous acyclovir treatment. Four days later the patient presented with a fulminant septicaemia. Despite an early intravenous antibiotic therapy with ciprofloxacin, piperacillin/combactam and vancomycin the patient died within 48 hours, shortly before the infective isolate was identified as Staphylococcus lugdunensis by polymerase chain reaction. CONCLUSION: despite S. lugdunensis belonging to the family of coagulase-negative staphylococci with an usually low virulence, infections with S. lugdunensis may be associated with an aggressive course and high mortality. This is the first report on a Staphylococcus lugdunensis septicaemia following a zoster bacterial superinfection of the pelvic region.  相似文献   
626.
The Angelchik prosthesis is an incomplete doughnut-shaped device composed of silicone elastomer used in the treatment of gastro-oesophageal reflux disease (GORD). It is used to encircle the lower oesophagus at the gastro-oesophageal junction (GOJ). The ease of the operation led to the insertion of over 25,000 such prostheses world-wide. However, a variety of major complications including intractable dysphagia, prosthesis migration and gastric erosion required a quarter of these devices to be removed. Development of adenocarcinoma in patients with Angelchik prosthesis is a rare occurrence. This article describes two patients who developed adenocarcinoma above their prosthesis and whose cardio-oesophagectomy was technically challenging due to the formation of a dense inflammatory capsule around the prosthesis. Our surgical approach to curative oesophageal resection with the Angelchik prosthesis in situ is also discussed.  相似文献   
627.
Taylor A, Wang D, Patel K, Whittall R, Wood G, Farrer M, Neely RDG, Fairgrieve S, Nair D, Barbir M, Jones JL, Egan S, Everdale R, Lolin Y, Hughes E, Cooper JA, Hadfield SG, Norbury G, Humphries SE. Mutation detection rate and spectrum in familial hypercholesterolaemia patients in the UK pilot cascade project. Cascade testing using DNA‐mutation information is now recommended in the UK for patients with familial hypercholesterolaemia (FH). We compared the detection rate and mutation spectrum in FH patients with a clinical diagnosis of definite (DFH) and possible (PFH) FH. Six hundred and thirty‐five probands from six UK centres were tested for 18 low‐density lipoprotein receptor gene (LDLR) mutations, APOB p.Arg3527Gln and PCSK9 p.Asp374Tyr using a commercial amplification refractory mutation system (ARMS) kit. Samples with no mutation detected were screened in all exons by single strand conformation polymorphism analysis (SSCP)/denaturing high performance liquid chromatography electrophoresis (dHPLC)/direct‐sequencing, followed by multiplex ligation‐dependent probe amplification (MLPA) to detect deletions and duplications in LDLR.The detection rate was significantly higher in the 190 DFH patients compared to the 394 PFH patients (56.3% and 28.4%, p > 0.00001). Fifty‐one patients had inadequate information to determine PFH/DFH status, and in this group the detection rate was similar to the PFH group (25.5%, p = 0.63 vs PFH). Overall, 232 patients had detected mutations (107 different; 6.9% not previously reported). The ARMS kit detected 100 (44%) and the MLPA kit 11 (4.7%). Twenty‐eight (12%) of the patients had the APOB p.Arg3527Gln and four (1.7%) had the PCSK9 p.Asp374Tyr mutation. Of the 296 relatives tested from 100 families, a mutation was identified in 56.1%. In 31 patients of Indian/Asian origin 10 mutations (two previously unreported) were identified. The utility of the ARMS kit was confirmed, but sequencing is still required in a comprehensive diagnostic service for FH. Even in subjects with a low clinical suspicion of FH, and in those of Indian origin, mutation testing has an acceptable detection rate.  相似文献   
628.
Prolapse of the lacrimal gland is an acquired clinical condition caused mainly by relaxation of the local suspending ligaments. Before an aesthetic blepharoplasty, there should be a preoperative clinical suspicion of lacrimal gland pathology for patients with bulging lateral thirds of the upper eyelids. It should be borne in mind that inadvertent removal of the lacrimal gland can lead to important alterations in ocular lubrication. This report describes two clinical cases of patients with lacrimal gland prolapse associated with dermatochalasis and their treatment.  相似文献   
629.
Neurotrophins are potent survival factors for developing and injured neurons. However, they are not being used to treat neurodegenerative diseases because of difficulties in administration and numerous side effects that have been encountered in previous clinical trials. Their biological activities use Trk (tropomyosin-related kinase) transmembrane tyrosine kinases. Therefore, one alternative approach is to use transactivation pathways such as adenosine 2A receptor agonists, which can activate Trk receptor signaling independent of neurotrophin binding. However, the relevance in vivo and applicability of these transactivation events during neurodegenerative and injury conditions have never been extensively studied. Here we demonstrate that motoneuron survival after facial nerve lesioning is significantly enhanced by transactivation of Trk receptor tyrosine kinases by adenosine agonists. Moreover, survival of motoneurons directly required the activation of the BDNF receptor TrkB and an increase in Akt (AKT8 virus oncogene cellular homolog) activity. The ability of small molecules to activate a trophic response by using Trk signaling provides a unique mechanism to promote survival signals in motoneurons and suggests new strategies for using transactivation in neurodegenerative diseases.  相似文献   
630.
学术背景:一般认为中枢神经系统损伤后,由于内在的再生能力差和外在环境抑制,损伤轴突不能再生。近年来研究证实脊髓损伤后采用一些改变其局部环境的方法,能促使损伤神经修复、再生及恢复脊髓部分神经功能。目的:移植的嗅鞘细胞通过加速轴突穿过受损脊髓的区域,从而恢复部分神经功能,有必要对嗅鞘细胞移植治疗脊髓损伤的基础和临床研究现状进行深入认识。检索策略:由该论文的研究人员应用计算机检索Pubmed数据库1994-01/2007-07的相关文献,检索词"spinal cord injury,Olfactory Ensheathing Cells,Neumtrophic Factors",并限定文章语言种类为English。同时计算机检索中国期刊全文数据库2000-01/2007-07的相关文献,检索词"嗅鞘细胞,脊髓损伤",并限定文章语言种类为中文。共检索到76篇文献,对资料进行初审,纳入标准:①文章所述内容应与嗅鞘细胞移植治疗脊髓损伤密切相关。②同一领域选择近期发表或在权威杂志上发表的文章。排除标准:①重复性研究。②Meta分析。文献评价:文献的来源主要是通过对嗅鞘细胞移植治疗脊髓损伤方面内容进行汇总分析。所选用的34篇文献中,4篇为综述,其余均为临床或基础实验研究。资料综合:①大量的基础和临床研究显示:脊髓损伤后采用一些改变其局部环境的方法,能促使损伤神经修复、再生和恢复脊髓部分冲经功能。在这些方法中,嗅鞘细胞被认为是治疗脊髓损伤最有前景的方法之一。②嗅鞘细胞具有许旺细胞和星形胶质细胞相似的特征,在其膜上表达出很多与细胞黏合和轴突生长相关的分子,还能分泌大量不同种类的神经营养和支持因子;实验证实嗅鞘细胞移植入各种脊髓损伤的模型表现出促进脊髓轴突再生的能力。③临床研究证实,嗅鞘细胞移植对脊髓损伤患者的脊髓神经功能恢复具有帮助作用,且安全性有保障。结论:采用嗅鞘细胞移植治疗脊髓损伤已被公认为非常有效且前景广阔的治疗方法之一。目前采用嗅鞘细胞移植治疗的晚期脊髓损伤患者为数尚少,还需要进一步观察研究其最终恢复程度和临床安全性;此外仍需探讨如何提高脊髓神经功能恢复的程度。  相似文献   
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