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101.
幽门螺杆菌感染相关的消化性溃疡患儿细胞免疫功能研究 总被引:9,自引:8,他引:9
目的 通过检测幽门螺杆菌 (Hp)感染相关的消化性溃疡 42例患儿外周血白细胞介素 2 (IL 2 )、可溶性白细胞介素 2受体 (sIL 2R)、白细胞介素 6和 8(IL 6和IL 8)及T淋巴细胞亚群 ,以探讨其免疫学发病机制。方法 IL 2、sIL 2R、IL 6、IL 8和T淋巴细胞亚群检测 ,分别采用ELISA、双抗体夹心ELISA和碱性磷酸酶 -抗碱性磷酸酶 (APAAP)标记法进行。结果 CD3 、CD4 、CD4 /CD8 和IL 2水平均显著低于对照组 (P均 <0 .0 1) ,而CD8 、sIL 2R、IL 6、IL 8水平均显著高于对照组 (P均 <0 .0 1)。结论 Hp感染相关的消化性溃疡患儿细胞免疫功能低下且紊乱 ,机体免疫功能障碍在该病的发生中起一定作用 相似文献
102.
Background
Application of perioperative thrombosis prophylaxis in head and neck surgery lacks consistent standards in Germany. Due to sparse data, the latest German S3 guideline concerning prophylaxis of thromboembolic events recommends a restrictive handling of anticoagulants in head and neck surgery, with few specific recommendations.Objective
The aim of this paper is to provide concrete clinical recommendations based on a systematic literature review and the S3 guidelines.Materials and methods
A keyword-based literature search was performed and the German S3 guideline “Prophylaxis of Venous Thromboembolic Events” was used to state the current level of evidence and provide a clinical algorithm.Results
Eight additional cohort studies dealing with the incidence of thromboembolic events in head and neck surgery were identified. There were no randomized controlled trials. In the proposed algorithm, a classification of dispositional (patient history) and expositional (operation time) risk into three groups enables preoperative risk evaluation indicating the individual demand for prophylaxis. In short operations without major tissue traumatization, routine drug-based thrombosis prophylaxis is not necessary, provided no third-grade risk factors (earlier thromboembolic event, coagulopathy, or malignant disease) are present. Low molecular weight heparins should be used as anticoagulants for drug-based prophylaxis.Conclusion
Prophylaxis of thromboembolic events in head and neck surgery is of high clinical relevance but there is currently limited evidence regarding its implementation. This paper is based on a systematic literature review and provides a clinical algorithm for head and neck surgeons.103.
卡托普利含服治疗高血压急症的疗效观察 总被引:2,自引:0,他引:2
目的以卡托普利舌下含服治疗高血压急症,并与利血平肌注治疗对照。方法卡托普利37.5mg舌下含服治疗高血压急症60例为治疗组,60例用利血平1.0mg肌注作对照。结果卡托普利组用药后15min即开始有显著的降压作用(P<0.001),30,60,120min后疗效更显著(P<0.001)。对照组利血平用药后15min血压无显著下降(P>0.05),30,60,120min血压明显下降(P<0.001)。二组比较,卡托普利组降压作用明显(P<0.001)。结论卡托普利舌下含服是治疗高血压急症较迅速、有效、安全、简便的降压方法,无明显不良反应 相似文献
104.
目的:研究丹参酮ⅡA磺酸钠注射液(STS)对大鼠肺成纤维细胞转化生长因子β1(TGF-β1)Smad信号通路的影响,探讨STS抑制肺成纤维细胞(LFB)增殖、转化的可能机制。方法:体外分离培养大鼠肺成纤维细胞,实验分为3组:①空白对照组;②TGF-β1刺激组;③联合处理组:STS+TGF-β1刺激组,培养48h,待细胞生长同步化后,用MTT法检测丹参酮ⅡA对肺成纤维细胞增殖的影响,用RT-PCR法分析丹参酮ⅡA磺酸钠和TGF-β1作用后肺成纤维细胞Smad3、Smad7 mRNA表达水平的变化,以及对Ⅰ型胶原mRNA的影响。结果:丹参酮ⅡA磺酸钠在80-640mg/L浓度范围对5μg/L TGF-β1刺激的肺成纤维细胞增殖均具有明显的抑制作用,并呈剂量依赖性(P<0.05);丹参酮ⅡA磺酸钠在浓度160mg/L时能明显下调TGF-β1刺激的肺成纤维细胞内Smad3 mRNA、Smad3/Smad7 mRNA及Ⅰ型胶原mRNA的表达(P<0.05),并能上调Smad7 mRNA表达(P<0.05)。结论:丹参酮ⅡA磺酸钠能抑制LFB的增殖、转化及胶原的合成,机制可能是丹参酮ⅡA磺酸钠下调了大鼠TGF-β1 Smad信号通道的Smad3/Smad7水平,从而抑制LFB的增殖、转化。 相似文献
105.
2002~2004年凯里市市区体检人群HBsAg携带状况分析 总被引:2,自引:0,他引:2
[目的]了解凯里市市区不同人群乙肝病毒感染状况,为制定预防控制策略提供参考。[方法]对凯里市市区2002-2004年到黔东南州疾病预防控制中心体检人群的HBsAg检查结果进行分析。[结果]合计检查15359人,HB—sAg阳性的939人,阳性率为6.11%。其中,机关单位体检者阳性率为5.98%,工厂企业体检者阳性率为11.27%,餐饮服务行业体检者阳性率为4.17%,门诊体检者阳性率为7.97%;男性阳性率为8.26%,女性阳性率为5.80%。不同单位、性别HBsAg阳性率的差异均有统计学意义(P〈0.01)。[结论]凯里市市区不同人群HBsAg阳性率不同。 相似文献
106.
Günter Grge Raimund Erbel Stephanie Nießing Frank Schn Peter Kearney JÜRgen Meyer 《Catheterization and cardiovascular interventions》1993,30(4):341-347
The present study focused on the accuracy and reproducability of measurements performed with a miniaturized pressure guidewire system (PGWS) under standardized in vitro conditions and in an isolated pig heart model. We used a pressure guide wire system provided by Pressure Guide?, Radi Medical Systems, Uppsala, Sweden. Pressures were recorded by a fiber optic pressure sensor located laterally and 3 cm from the distal end. The basic principle is that the element modulates an optical reflection by pressure induced elastic movements. The light source is an emitting diode in the control unit. The PGWS replaces a standard 0.018 in. guidewire. The PGWS was introduced through a Y-adapter in a recirculating perfusion model, consisting of tubing with internal diameters from 1.00 to 4.00 mm. Different perfusion pressures (range 20–140 mm Hg) were generated by a pressure controlled roller pump. Results: Different lumen sizes from 1 to 4 mm had no influence on the measurements. (a) In a range from 20 to 140 mm Hg no significant differences were found between the perfusion pressure and the pressures obtained by the PGWS, resulting in an r-value of 0.99 and an equation of y = 1.04x + 1.9. (b) In pressure measurements proximal and distal of an artificial stenoses resulting in gradients from 0 to 100 mm Hg, the PGWS correctly identified the pressure difference with an equally high accuracy, 1,2, and 3 cm behind the stenoses. The equation was y = 1.06x + 5, with an r-value of 0.97. (c) If the PGWS was introduced in curved segments of the phantoms, differences were found that correlated with the diameter of the bend and the angulation. If the transducer element was positioned in the convexity of the tubing, pressures were higher than the perfusion pressure. They were lower when if the pressure element was moved towards the concave part of the tubing. At a perfusion pressure of 100 mm Hg, a diameter of 2 cm and an angulation of 45°, no significant difference was found; but an angulation of 160° in the same phantom caused a difference of ± 45 mm Hg. (d) In isolated swine hearts (n = 6), the correlation of aortic perfusion pressure with the PGWS values (proximal LAD) was y = 1.02x + 3, r = 0.92. In the most bended part of the left circumflex artery, the maximal mean pressure difference was ± 28 mm Hg at a perfusion pressure of 100 mm Hg, depending on the position of the catheter. Conclusion: The PGWS has the potential to accurately determine pressures within coronary arteries, if measurements within bends of > 45° are avoided.© 1993 Wlley-Liss, Inc 相似文献
107.
目的探讨胃底静脉栓塞联合部分性脾动脉栓塞预防肝硬化食管胃底曲张静脉破裂出血的有效性。方法将125例肝硬化门脉高压患者随机分为胃底静脉栓塞联合部分性脾动脉栓塞组(A组,60例)和胃底静脉断流加脾切除组(B组,65例)分别进行治疗,对比两组治疗前后内镜下食管胃底曲张静脉变化、血清ALT、总胆红素水平、再出血率、术后并发症发生率及术后死亡率等。结果治疗后1个月A、B两组共112例患者接受胃镜复查,两组食管胃底曲张静脉消失率(分别为90.9%和87.7%)差异无统计学意义(P〉0.05)。治疗后1周,B组血清ALT、总胆红素水平(分别为156U/L和86μmol/L)显著高于A组(分别为65U/L和34μmol/L)及治疗前(分别为51U/L和45μmol/L)。A、B两组曲张静脉破裂再出血率分别为7.3%和12.3%,差异无统计学意义(P〉0.05),但术后并发症发生率(分别为3.3%和18.5%)、Child-Pugh C级患者死亡率(分别为1/15和6/11)及急性胃黏膜出血发生率(分别为20.0%和45.6%)差异有统计学意义(P〈0.05)。结论胃底静脉栓塞联合部分性脾动脉栓塞预防肝硬化食管胃底静脉曲张破裂出血的近期疗效优于胃底静脉断流加脾切除术。该技术对患者创伤小、并发症少、手术死亡率低,特别对于肝功能较差、不能耐受外科手术的患者是较为理想的选择。 相似文献
108.
目的 蛋白激酶Cη(PKCη)转基因对心脏表型的影响。 方法表达低水平 (Tg PKCη L)和高水平 (Tg PKCη H)靶心脏野生型PKCη的转基因小鼠通过标准技术被建立。Tg PKCη L、Tg PKCη H阳性鼠通过PCR和Southern印迹鉴定 ,转基因阴性鼠作为研究对照。用非开胸经颈总动脉插管的显微外科技术测血液动力学指标和评价小鼠左室收缩功能。Western免疫印迹分析α 骨骼肌肌动蛋白 (α \|SkeletalMuscleActin)和PKCη表达水平。苏木精染色进行心脏组织学分析。 结果与对照鼠相比Tg PKCη L、Tg PKCη H鼠基线左室最大收缩压、左室收缩压、最大收缩速率 (dp/dt)、 dp/dt、左室舒张末压、舒张压均无明显变化 (均P >0 0 5 ) ,异丙肾上腺素激发后左室dp/dt剂量依赖的升高无明显抑制 (均P >0 0 5 )。此外 ,Tg PKCη H、Tg PKCη L鼠心脏 /体重比、心肌α 肌动蛋白表达无显著变化 ,(P >0 0 5 ) ,心肌组织学分析表现了正常的心肌细胞形态。结论 低水平和高水平PKCη的转基因过渡表达未导致心肌肥厚、心衰表型的出现。用非开胸经颈总动脉插管的显微外科方法能敏感、准确地评价小鼠左室收缩功能。 相似文献
109.
110.
Mohsen Alavash Claus C. Hilgetag Christiane M. Thiel Carsten Gießing 《Human brain mapping》2015,36(9):3542-3562
Previous studies on multitasking suggest that performance decline during concurrent task processing arises from interfering brain modules. Here, we used graph‐theoretical network analysis to define functional brain modules and relate the modular organization of complex brain networks to behavioral dual‐task costs. Based on resting‐state and task fMRI we explored two organizational aspects potentially associated with behavioral interference when human subjects performed a visuospatial and speech task simultaneously: the topological overlap between persistent single‐task modules, and the flexibility of single‐task modules in adaptation to the dual‐task condition. Participants showed a significant decline in visuospatial accuracy in the dual‐task compared with single visuospatial task. Global analysis of topological similarity between modules revealed that the overlap between single‐task modules significantly correlated with the decline in visuospatial accuracy. Subjects with larger overlap between single‐task modules showed higher behavioral interference. Furthermore, lower flexible reconfiguration of single‐task modules in adaptation to the dual‐task condition significantly correlated with larger decline in visuospatial accuracy. Subjects with lower modular flexibility showed higher behavioral interference. At the regional level, higher overlap between single‐task modules and less modular flexibility in the somatomotor cortex positively correlated with the decline in visuospatial accuracy. Additionally, higher modular flexibility in cingulate and frontal control areas and lower flexibility in right‐lateralized nodes comprising the middle occipital and superior temporal gyri supported dual‐tasking. Our results suggest that persistency and flexibility of brain modules are important determinants of dual‐task costs. We conclude that efficient dual‐tasking benefits from a specific balance between flexibility and rigidity of functional brain modules. Hum Brain Mapp 36:3542–3562, 2015. © 2015 Wiley Periodicals, Inc. 相似文献