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21.
This is the first study to examine the hypothesis that prolonged sitting is associated with procoagulant changes in the local lower-limb venous system. A comparison was made with upper-limb venous changes. Changes in markers of thrombin generation, fibrinolysis, endothelial perturbation and haemoconcentration were analysed as 10 healthy adult male participants sat for 8 h. The change in foot volume was estimated. Subjective venous thromboembolism assessment was undertaken hourly, along with 2-week and 4-week safety follow-up for clinical events.Expected increases in median prothrombin fragments 1 and 2, thrombin-antithrombin complex and D-dimer were not observed in either limb. An increase greater than 45% in the median tissue plasminogen activator and plasminogen activator-1 molar ratio (t-PA/PAI-1), and a decrease greater than 15% in median soluble thrombomodulin were noted in both limbs. Median haematocrit decreased minimally (1%) in the lower limbs, while the foot volume increased by 4%. Subjects experienced vague symptoms after 6 h of sitting, but none developed symptomatic venous thromboembolism. Upper and lower-limb changes in biomarkers did not correlate, except those in t-PA/PAI-1 ratio and plasminogen activator-1. Significant correlation was found between changes in the lower-limb t-PA/PAI-1 ratio and right foot volume.This study originally reveals that even in the lower limbs, prolonged daytime cramped sitting is not associated with significant procoagulant changes in healthy adult male volunteers, and confirms a previous observation that local lower-limb venous changes are not identically reflected in the upper limbs.  相似文献   
22.
抑郁症患者心理治疗的临床研究   总被引:2,自引:1,他引:1  
目的 通过对照的方法,对抑郁症患者使用单纯抗抑郁药物治疗和药物合并心理治疗的疗效进行比较,探讨心理治疗在抑郁症患者治疗中的作用.方法 选取抑郁症患者120例,随机分成两组.对照组60例,男女各半,年龄18~65岁,平均(38.9±2.53)岁;心理治疗组60例,男女各半,年龄19~67岁,平均(39.7±3.12)岁.两组患者均给予帕罗西汀(商品名赛乐特)20mg/d,对照组单纯用药物治疗,心理治疗组药物加心理治疗,疗程8周.分别于第0周(基线)、干预后第2周、第4周、第8周使用汉密顿抑郁量表(HAMD)和抑郁自评量表(SDS)进行评分.结果 药物合并心理治疗组的治疗效果优于对照组(P<0.05),且治疗时间越长,两组的疗效差异越明显.结论 心理治疗对抑郁症患者的康复有积极的作用,药物治疗合并心理治疗较单纯药物治疗更有利.  相似文献   
23.
Summary It has been suggested that inherited traits play a role in the development of osteoporosis by providing a background for the modulation of gene expression. In this study, we examine the influence of the different alleles of alpha2-HS glycoprotein (AHSG), a protein of the bone matrix, on quantitative estrogens, estrone and estradiol, and bone measures, bone area and density. Estrogens provide a protective effect against fractures in older women and were thus included in the analyses. Isoelectric focusing of AHSG from sera followed by immunoblotting was used to type 163 white post-menopausal women participating in a clinical trial of the effects of walking on bone loss. Plasma hormones were measured by a combination of extraction, column chromatography, and radioimmunoassay; bone measures on the dominant radius were determined with computerized tomography. Analysis of variance was done on estrogen and bone measures after controlling for the effects of age and body mass index. The two major alleles of AHSG result in three phenotypes, designated AHSG 1-1, AHSG 2-1, and AHSG 2-2. The AHSG 1-1 homozygote showed a decreased concentration of estradiol, the AHSG 2-2 homozygote showed an increased concentration, and the AHSG 2-1 heterozygote was intermediate (P=0.001). Estrone demonstrated a similar pattern in residual analysis although it did not reach statistical significance.  相似文献   
24.
OBJECTIVE Autonomous cortisol secretion without clinical stigmata of Cushing's syndrome (CS) has been recently recognized and termed pre-clinical or sub-clinical CS. The common assumption is that CS is an extremely rare cause of uncontrolled diabetes; however, the prevalence of this entity has not been studied. We assessed the prevalence of pre-clinical CS among obese patients with uncontrolled diabetes. PATIENTS AND DESIGN (1) In a retrospective analysis, the medical records of 63 patients with endogenous CS were reviewed. (2) In a cross-sectional study, 90 obese patients (BMI >25 kg/m2) followed in a University Hospital and the local Health Fund endocrine and diabetes clinics, with poorly controlled diabetes (glycosylated haemoglobin >9%), underwent an overnight 1 mg dexamethasone suppression. In patients with non-suppressible cortisol levels (>140 nmol/l), Liddle's 2 and 8 mg dexamethasone suppression tests and imaging studies were performed. MEASUREMENTS The prevalence of poorly controlled diabetes, the major presenting symptom of CS, was assessed in the retrospective analysis. The prevalence of ‘true’ CS and the false positive rate in the overnight dexamethasone suppression test were calculated. The endocrine evaluation of the patients with pre-clinical CS and the effects of surgical cure on glycaemic control are described. RESULTS In the retrospective analysis, 11 (17.5%) had diabetes and 2 (3.2%) lacked the classic physical characteristics of the syndrome. In the cross-sectional study, 4 patients failed to suppress plasma cortisol (<140 nmol/l). In one patient the diagnosis of CS was not confirmed by a standard Liddle’s test and was therefore considered false positive. In the other 3, the diagnosis of CS was confirmed (prevalence of 3.3%, 95% confidence interval 1–9%). In all other patients the overnight cortisol suppression test was normal (cortisol level 47.3 ± 2.5 nmol/l (mean ± SEM)). After surgical treatment of CS, glycaemic control was markedly improved in all 5 patients (2 from retrospective and 3 from cross-sectional studies). CONCLUSIONS The prevalence of pre-clinical Cushing's syndrome in obese patients with poorly controlled diabetes appears to be considerably higher than previously believed. The overnight dexamethasone suppression test proved to be a simple, sensitive and highly specific screening test for Cushing's syndrome despite the presence of obesity and hyperglycaemia.  相似文献   
25.
目的研究应用力学因素检测膝关节功能方法的有效性.方法利用测力平台测量得到人体下肢在运动过程中的力学曲线,用数学方法确定力学曲线的最大值F和曲线特征值R.结果给出51例骨关节炎患者的分析数据,并给出30例正常人的结果作为对照.结论应用力学因素可以有效地检测膝关节功能状态.  相似文献   
26.
Reporter probe 9-(4-18F-fluoro-3-[hydroxymethyl]butyl)guanine (18F-FHBG) and reporter gene mutant herpes simplex virus type 1 thymidine kinase (HSV1-sr39tk) have been used for imaging reporter gene expression with PET. Current methods for quantitating the images using the percentage injected dose per gram of tissue do not distinguish between the effects of probe transport and subsequent phosphorylation. We therefore investigated tracer kinetic models for 18F-FHBG dynamic microPET data and noninvasive methods for determining blood time-activity curves in an adenoviral gene delivery model in mice. METHODS: 18F-FHBG (approximately 7.4 MBq [approximately 200 microCi]) was injected into 4 mice; 18F-FHBG concentrations in plasma and whole blood were measured from mouse heart left ventricle (LV) direct sampling. Replication-incompetent adenovirus (0-2 x 10(9) plaque-forming units) with the E1 region deleted (n = 8) or replaced by HSV1-sr39tk (n = 18) was tail-vein injected into mice. Mice were dynamically scanned using microPET (approximately 7.4 MBq [approximately 200 microCi] 18F-FHBG) over 1 h; regions of interest were drawn on images of the heart and liver. Serial whole blood 18F-FHBG concentrations were measured in 6 of the mice by LV sampling, and 1 least-squares ratio of the heart image to the LV time-activity curve was calculated for all 6 mice. For 2 control mice and 9 mice expressing HSV1-sr39tk, heart image (input function) and liver image time-activity curves (tissue curves) were fit to 2- and 3-compartment models using Levenberg-Marquardt nonlinear regression. The models were compared using an F statistic. HSV1-sr39TK enzyme activity was determined from liver samples and compared with model parameter estimates. For another 3 control mice and 6 HSV1-sr39TK-positive mice, the model-predicted relative percentage of metabolites was compared with high-performance liquid chromatography analysis. RESULTS: The ratio of 18F-FHBG in plasma to whole blood was 0.84 +/- 0.05 (mean +/- SE) by 30 s after injection. The least-squares ratio of the heart image time-activity curve to the LV time-activity curve was 0.83 +/- 0.02, consistent with the recovery coefficient for the partial-volume effect (0.81) based on independent measures of heart geometry. A 3-compartment model best described 18F-FHBG kinetics in mice expressing HSV1-sr39tk in the liver; a 2-compartment model best described the kinetics in control mice. The 3-compartment model parameter, k3, correlated well with the HSV1-sr39TK enzyme activity (r2 = 0.88). CONCLUSION: 18F-FHBG equilibrates rapidly between plasma and whole blood in mice. Heart image time-activity curves corrected for partial-volume effects well approximate LV time-activity curves and can be used as input functions for 2- and 3-compartment models. The model parameter k3 from the 3-compartment model can be used as a noninvasive estimate for HSV1-sr39TK reporter protein activity and can predict the relative percentage of metabolites.  相似文献   
27.
肝癌病人血浆和癌组织中血栓调节蛋白的检测   总被引:3,自引:0,他引:3  
目的 检测肝癌病人血浆和肝癌组织中血栓调节蛋白 (TM )的表达 ,探讨TM与肝癌临床病理特征的关系。方法 用酶联免疫吸附夹心法检测 45例肝癌和 6例肝良性占位病人手术前后的血浆TM水平 ;用免疫组织化学法检测肝癌及肝良性占位组织中的TM蛋白表达水平。结果 术前肝癌组血浆TM水平 ( 10 .2± 5 .7)ng/mL明显高于肝良性占位组 ( 6.1± 2 .2 )ng/mL和正常人对照组 ( 5 .7± 1.0 )ng/mL ,P <0 .0 5 ;术前TM血浆水平肝癌伴门静脉癌栓组 ( 6.9± 4.5 )ng/mL和多发肝癌结节组 ( 8.1± 4.6)ng/mL明显低于无门静脉癌栓组( 11.4± 5 .6)ng/mL和单发肝癌结节组 ( 11.5± 5 .9)ng/mL ,P <0 .0 5 ;40例肝癌病人肝癌切除术前TM水平( 10 .8± 5 .3 )ng/mL与肝癌切除术后 ( 7.6± 4.2 )ng/mL相比差异显著 ,P <0 .0 5。肝良性占位组术前与术后相比差异无显著性 ,P >0 .0 5。肝癌组织中TM蛋白表达阳性的病人术前血浆TM水平明显高于TM表达阴性者 ,P <0 .0 5 ;而术后血浆TM水平两者则无显著性差异 ,P >0 .0 5。结论 肝癌病人血浆中TM水平升高 ,TM水平的高低与门静脉癌栓的形成有关  相似文献   
28.
Valiolamine和1,3-二羟基丙酮在Pd/C作用下催化氢化得到伏格列波糖,收率75%.  相似文献   
29.
We hypothesized that increased ambient concentrations of metals, as a consequence of escalating urbanization and industrialization of the Gulf region will respond in increased contamination of edible fish species. In this study, we report concentrations of chromium, manganese, cobalt, copper, zinc, arsenic, cadmium, mercury and lead in meat and liver of wild Red-spot emperor (Lethrinus lentjan) from three sampling points at the UAE coast. Analysis was performed by the ICP-MS/microwave digestion. Our study has shown that meat and liver metal content was significantly higher in areas with higher industrial activity, although metal values did not exceed permitted levels of fish for human consumption.  相似文献   
30.
切开复位内固定治疗Gartland Ⅲ型肱骨髁上骨折   总被引:2,自引:0,他引:2  
目的探讨切开复位内固定治疗Gartland Ⅲ型肱骨髁上骨折的疗效。方法1999年10月-2005年4月,对62例平均年龄7.5岁的患儿,应用切开复位克氏针固定治疗Gartland Ⅲ型肱骨髁上骨折。其中伸直尺偏型41例,伸直桡偏型18例,伸直中间型3例;无伴发血管、神经损伤和筋膜室间隔综合征。闭合性骨折47例,开放性骨折15例。结果术后56例获得随访,随访时间为6~15个月,平均11.5个月。所有骨折均获得愈合。根据Flynn标准进行疗效评价,其中优22例(占39.3%),良21例(37.5%),可9例(16.1%),差4例(7.1%)。伤后8h内手术的优良率为89.7%,伤后8h后手术的优良率为63.0%。直接手术治疗的优良率为90.1%,曾接受手法复位的优良率为67.7%。结论切开复位内固定治疗Gartland Ⅲ型肱骨髁上骨折可取得满意的疗效,是安全、有效的治疗方法。  相似文献   
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