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91.
目的比较5种布鲁氏菌核酸实时荧光PCR检测试剂盒的一致性和检出能力,为临床实验室选择检测方法和布鲁氏菌的诊断提供参考依据。方法选用经病原学检测确定为布鲁氏菌阳性的血液样本38份,健康人的血液样本24份,潘氏变形杆菌、溶藻弧菌、河弧菌、铜绿假单胞菌、肺炎克雷伯菌DNA各1份,使用5种试剂盒(编号A-E)分别进行核酸检测,比较5种试剂盒临床样本检测的一致性;选择1份阳性样本核酸用无RNA酶水梯度稀释得到5个浓度(浓度1:4453.13 fg/μL,浓度2:1113.28 fg/μL,浓度3:278.32 fg/μL,浓度4:69.58 fg/μL,浓度5:17.40 fg/μL),每个浓度使用5种试剂盒(编号A-E)分别进行3次检测,比较5种试剂盒的阳性检出率及批内重复性。结果5种试剂盒检测67份DNA样品的符合率稍有不同,试剂盒ABDE的符合率均为100%,试剂盒C的符合率为98.51%。批内重复性显示5种试剂盒在浓度1、浓度2、浓度3水平重复检测DNA的Ct值变异系数均<5%;在浓度1与浓度4梯度区间,试剂盒的阳性检出能力比较显示试剂盒A、B、D较高,为11/12,试剂盒C和E较低,为8/12。结论5种试剂盒的真实性和可靠性较好,灵敏度和符合率稍有差别,特异度均为100%;重复性较好,检测性能良好。部分试剂盒对弱阳性样本的检出能力不强,该类样本可使用多种试剂盒复核,以保障结果的准确性。  相似文献   
92.
在我国大规模人群调查显示,脑卒中年发病率为109.7~217/10万,且随年龄而增长,脑卒中患者为医院感染的高危人群,其感染发生率明显高于其他疾病。为了解脑卒中患者的医院感染危险因素,预防和控制医院感染的发生,现对海安肿瘤医院院收治的396例脑卒中患者病历资料进行调查,分析脑卒中患者医院感染的危险因素和特点,为有效控制院内感染提供依据。  相似文献   
93.
目的探讨急性阑尾炎多层螺旋CT征象与血清炎性标志物的关系。方法收集2012年1月至2013年12月于同济大学附属杨浦医院经手术病理证实的具有完整临床及影像资料的急性阑尾炎患者66例,对所有患者的急性阑尾病变程度行CT分级,分析其与患者白细胞(WBC)计数、中性粒细胞百分比(NEUT%)及血清C反应蛋白(CRP)水平的相关性。结果急性阑尾炎CT分级与患者WBC计数与CRP水平呈正相关(P0.05),穿孔性阑尾炎患者NEUT%及CRP水平明显高于其他患者。CRP水平与阑尾直径、阑尾积液、回盲部变化、阑尾周围炎性条纹、小肠积液呈正相关(P0.05),WBC计数与回盲部变化及阑尾周围炎性条纹呈正相关(P0.05)。结论WBC计数及CRP水平与急性阑尾炎CT分级有关,CRP对急性阑尾炎的诊断及其严重程度的判断更有优势;CRP、NEUT%是穿孔性阑尾炎的重要预测因子,WBC可以更好地发现早期阑尾周围的炎性反应,综合分析CT表现与血清炎性标志物能更准确地诊断急性阑尾炎。  相似文献   
94.
95.
Background Previous studies reported a close relationship between obesity and insulin resistance in the essential hypertensive patients. Objective In this study, we examined the relationship between the skin fold thickness and insulin resistance then developed a formula to estimate the insulin resistance index according to the skin fold thickness in the essential hypertensive patients. Subjects and Methods Medical records of 80 patients (37 males, 43 females) were reviewed and the data were tabulated. Anthropometric indexes (including height, weight, waist circumference, hip circumference, and skins fold thickness at 5 fatty difference points on the Erdheim diagram), fasting plasma glucose and insulin concentration were recorded. The mean age was 57.0 ?9.2 years. The insulin resistance index was calculated following the Homeostasis Model Assessment (HOMA) formula. Results Compared with the group with BMI < 23 kg/m2, the group with BMI≥23 kg/m2 had higher fasting insulin concentration (8.85±4.97 pmol/L vs 15.60±8.70 pmol/L, P<0.001 ) and higher insulin resistance index in ( 2.15±1,24 vs 3.76±2.22, P<0.001). No significant difference in fasting plasma insulin concentration, insulin resistance index between male and female was observed (P > 0.05). There was a positive correlation between skin fold thickness and the fasting insulin concentration and insulin resistance index. The skin fold thickness at point A8 had the best coefficient correlated with fasting plasma insulin(r=0.79, P < 0.001) and insulin resistance index (r= 0.79, P < 0.001). A formula to estimate the insulin resistance index by skin fold thickness at point A8 as: Insulin resistance index = 0.12×[skin fold thickness at A8 point (mm)] - 1. Conclusion: In the essential hypertensive patients, the formula to estimate insulin resistance index as 0.12×[skin fold thickness at A8 point (mm)]-1 may predict accurately the level of insulin resistance. (J Geriatr Cardiol 2005; 2(4):228-232 )  相似文献   
96.
AIM: With the availability of a minimally invasive approach, anti-reflux surgery has recently experienced a renaissance as a cost-effective alternative to life-long medical treatment in patients with gastroesophageal reflux disease (GERD). We are not aware of the fact whether reflux episodes causing complaints for a long time i.e., at least for one year are associated with metabolic changes in the lower esophageal sphincter, and if so, whether these may influence functional results achieved after anti-reflux surgery. METHODS: Between 1 January 2001 and 31 December 2002 we performed anti-reflux surgery on 79 patients. Muscle samples were taken from the lower esophageal sphincter (LES) in 33 patients during anti-reflux surgery. Inclusion criteria were: LES resting pressure below 10 mmHg and a marked, pH proven acid exposure to the esophagus of at least one year's duration, causing subjective complaints and requiring continuous proton pump inhibitor treatment. Control samples were obtained from muscle tissue in the gastroesophageal junction that had been removed from 17 patients undergoing gastric or esophageal resection. Metabolic and lysosomal enzyme activities and special protein concentrations 16 parameters in total were evaluated in tissue taken from control specimens and tissue taken from patients with GERD. The biochemical parameters of these intra-operative biopsies were used to correlate the results of anti-reflux operations (Visick Ⅰ and Ⅱ-Ⅲ). RESULTS: In the reflux-type muscle, we found a significant increase of the energy-enzyme activities e.g., creatine kinase, lactate dehydrogenase, β-hydroxybutyrate dehydrogenase, and aspartate aminotransaminase-. The concentration of the structural protein S-100 and the myofibrillar protein troponin Ⅰ were also significantly increased. Among lysosomal enzymes, we found that the activities of cathepsin B, tripeptidyl-peptidase Ⅰ, dipeptidyl-peptidase Ⅱ, β-hexosaminidase B, β-mannosidase and β-galactosidase were significantly decreased as compared to the control LES muscles. By analyzing the activity values of the 9 patients in Visick groups Ⅱ and Ⅲ at two months post-surgery, we found a significant increase in the activity of the so-called energy-enzyme values and in the concentration of structural and myofibrillar proteins as compared to the rest of the reflux patients. CONCLUSION: Our results call attention to the metabolic changes that occurred in the LES muscles of reflux patients. The developing hypertrophy-like changes of LES muscles may be a reason for complaints after anti-reflux surgery, which consisted mainly of reports of persisting dysphagia.  相似文献   
97.
98.
Unipolar Characteristics of CFAEs. Background: The noncontact mapping (NCM) system possesses the merit of global endocardial recording for unipolar and activation mapping. Objective: We aimed to evaluate the unipolar electrogram characteristics and activation pattern over the bipolar complex fractionated atrial electrogram (CFAE) sites during atrial fibrillation (AF). Methods: Twenty patients (age 55 ± 11 years old, 15 males) who underwent NCM and ablation of AF (paroxysmal/persistent = 13/7) were included. Both contact bipolar (32–300 Hz) and NCM virtual unipolar electrograms (0.5–300 Hz) were simultaneously recorded along with the activation pattern (total 223 sites, 11 ± 4 sites/patient). A CFAE was defined as a mean bipolar cycle length of ≤ 120 ms with an intervening isoelectric interval of more than 50 ms (Group 1A, n = 63, rapid repetitive CFAEs) or continuous fractionated activity (Group 1B, n = 59, continuous fractionated CFAEs), measured over a 7.2‐second duration. Group 2 consisted of those with a bipolar cycle length of more than 120 ms (n = 101). Results: The Group 1A CFAE sites exhibited a shorter unipolar electrogram cycle length (129 ± 11 vs 164 ± 20 ms, P < 0.001), and higher percentage of an S‐wave predominant pattern (QS or rS wave, 63 ± 13% vs 35 ± 13%, P < 0.001) than the Group 2 non‐CFAE sites. There was a linear correlation between the bipolar and unipolar cycle lengths (P < 0.001, R = 0.87). Most of the Group 1A CFAEs were located over arrhythmogenic pulmonary vein ostia or nonpulmonary vein ectopy with repetitive activations from those ectopies (62%) or the pivot points of the turning wavefronts (21%), whereas the Group 1B CFAEs exhibited a passive activation (44%) or slow conduction (31%). Conclusions: The bipolar repetitive and continuous fractionated CFAEs represented different activation patterns. The former was associated with an S wave predominant unipolar morphology which may represent an important focus for maintaining AF. (J Cardiovasc Electrophysiol, Vol. 21, pp. 640‐648, June 2010)  相似文献   
99.
Stoolman  LM; Yednock  TA; Rosen  SD 《Blood》1987,70(6):1842-1850
Lymphocyte recirculation begins with the attachment of circulating cells to the structurally distinctive postcapillary venules of lymphoid organs termed high-endothelial venules (HEVs). In both rodents and humans, the attachment of lymphocytes to the HEVs of peripheral lymph nodes (PNs) on the one hand and gut-associated lymphoid tissues (GALTs) on the other appears to involve discrete adhesive structures on the surfaces of the interacting cells. In rodents, we previously showed that a carbohydrate-binding receptor at the lymphocyte surface participates in the attachment to the HEV of peripheral nodes. The studies reported herein document the involvement of a similar receptor in the selective attachment of human peripheral blood lymphocytes to the HEVs of PNs. We argue that the close functional relationship between the human and rodent receptors indicates that this component of the adhesive interaction has been conserved through evolution.  相似文献   
100.
McGrath  HE; Liang  CM; Alberico  TA; Quesenberry  PJ 《Blood》1987,70(4):1136-1142
We have previously reported that lithium chloride (LiCl) stimulates the production of granulocyte-macrophage colony-forming cells (GM-CFC), pluripotent stem cells (CFU-S), and differentiated granulocytes, macrophages and megakaryocytes in murine Dexter marrow cultures and that this effect appears to be mediated indirectly by a radioresistant adherent marrow cell. In this study we have established that exposure of murine Dexter cultures to LiCl (4 mEq/L) causes an increase of colony-forming cell megakaryocytes (CFU-meg) over 1 to 6 weeks of culture in both supernatant (188% to 611%) and stromal phases (123% to 246%). Moreover, we have shown that lithium treatment of either irradiated (1,100 rad) or unirradiated stromal cells increased production of activities stimulating formation of megakaryocyte, granulocyte, macrophage, and mixed lineage colonies and proliferation of the factor-dependent cell line, FDC-P1. This FDC-P1 stimulatory activity was completely blocked by an antibody to purified recombinant granulocyte-macrophage colony stimulating factor (rGM-CSF). The baseline or lithium-induced--stromal-derived bone marrow colony stimulating activity was partially blocked by the antibody to rGM-CSF and by an antibody to purified colony stimulating factor I (CSF-1); the two antibodies combined resulted in greater than 90% inhibition of the lithium-induced marrow stimulatory activity. In addition, radioimmunoassay (RIA) showed that although CSF-1 was detectable in supernatants of these cultures, exposure to lithium did not increase CSF-1 levels. These data indicate that Dexter stromal cells produce CSF- 1 and GM-CSF and that lithium appears to exert its stimulatory effects on in vitro myelopoiesis by inducing production of GM-CSF.  相似文献   
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