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排序方式: 共有1417条查询结果,搜索用时 31 毫秒
71.
幽门螺杆菌粪便抗原检测——一种新的非侵入性诊断方法 总被引:7,自引:1,他引:7
目的:评估幽门螺杆菌粪便抗原(HpSA)榆测诊断Hp感染的可靠性。方法:收集43例接受胃镜检查患者的粪便标本,用一种市售的ELISA试剂盒检测HpSA:以尿素酶试验.培养和涂片染色检测Hp作为“金标准”,培养和/或涂片染色阳性定为Hp感染。结果:“金标准”诊断Hp阳性24例,阴性19例。“金标准”阳性的24例HpSA检测均阳性,阴性的19例HpSA检测18例阴性和1例阳性。HpSA试验的敏感性为100%(24/24),特异性为94.7%(18/19),总的诊断准确率为97.6%(42/43)。结论:HpSA试验是一简便、非侵入性、准确诊断Hp感染的新方法。 相似文献
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73.
G. Erdogan D.Z. Okyay S. Yurtlu V. Hanci H. Ayoglu B. Koksal I.O. Turan 《International Journal of Obstetric Anesthesia》2010,19(4):438-440
We present the successful use of perioperative non-invasive mechanical ventilation in a morbidly obese pregnant woman with bronchial asthma, severe preeclampsia and pulmonary edema undergoing an emergency cesarean delivery with spinal anesthesia. The combination of non-invasive mechanical ventilation with neuraxial anesthesia may be of value in selected parturients with acute or chronic respiratory insufficiency requiring surgery. 相似文献
74.
Lisa S. Hayward Rebecca K. Booth Samuel K. Wasser 《General and comparative endocrinology》2010,169(2):117-445
Avian endocrinology is a productive field that could benefit from increased application of non-invasive techniques. Although assay protocols vary, most studies that measure hormone metabolites in avian feces struggle with an artificial effect of sample mass on steroid metabolite concentration. Hormone metabolite concentrations measured in small samples are consistently higher than concentrations in larger samples, and this appears to be due to multiple methodological problems. We systematically tested several causal hypotheses for the mass effect. Based on results from these tests, we modified and validated our assay protocol to effectively eliminate the mass effect. Future studies should implement the following procedures when measuring hormone metabolites from small fecal samples (particularly of birds and reptiles): (1) remove urates from the fecal sample as completely as possible; (2) lyophilize the sample prior to extraction; (3) maximize accuracy of small mass measurements; (4) increase the volume of ethanol in the extraction to 15 ml per 0.05-0.1 g of dried feces; and (5) eliminate ethanol from all samples prior to radioimmunoassay by drying down extract solutions and rehydrating in buffer. By applying these precautions we successfully eliminated the mass effect from fecal samples ranging in mass from 0.001 to 0.1 g using a radioimmunoassay commonly employed for studies of fecal glucocorticoid metabolites. These corrections also resulted in a more than 3-fold increase in effect size in glucocorticoid concentrations from a controlled test of the effects of 1 h motorcycle exposure on northern spotted owls. These methods have important implications not only for avian studies, but for any study measuring hormone metabolites from small fecal samples. 相似文献
75.
Eli Vlaisavljevich Gabe Owens Jonathan Lundt Dejan Teofilovic Kimberly Ives Alexander Duryea Jim Bertolina Theodore H. Welling Zhen Xu 《Ultrasound in medicine & biology》2017,43(6):1237-1251
This study investigates the safety profile for use of histotripsy, a non-invasive ultrasonic ablation method currently being developed for the treatment of liver cancer, for liver ablation in an in vivo porcine model. Histotripsy treatments were applied to the liver and hepatic veins of 22 porcine subjects, with half of the subjects receiving systemic heparinization. Vital signs (heart rate, blood pressure, temperature, electrocardiogram and SpO2) were monitored throughout the procedure and for 1 h post-treatment. Blood was drawn at six points during the experiment to analyze blood gases, liver function and free hemoglobin levels. All treatments were guided and monitored by real-time ultrasound imaging. After treatment, the tissue was harvested for histological analysis. Results indicated that histotripsy generated well-defined lesions inside the liver and around the treated hepatic veins of all subjects in both treatment groups. Vital signs and blood analysis revealed that animals responded well to histotripsy, with all animals surviving the treatment. One animal in the non-heparinized group had a transient increase in pH and decreases in blood pressure, heart rate and PCO2 during the 15-min vessel treatment, with these changes returning to baseline levels soon after the treatment. Overall, the results indicate that histotripsy can safely be performed on the liver without the need for systemic heparinization, even in regions containing large hepatic vessels, supporting its future use for the treatment of liver cancer. 相似文献
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77.
For successfully raising offspring, long-term monogamous pair partners need to be behaviorally and hormonally coordinated. In the monogamous, biparental greylag geese (Anser anser) a dyadic pairbond-specific measure, ‘within-pair testosterone compatibility’ (TC) indicated how closely synchronized are seasonal androgen levels, which co-varied with reproductive output. Males, in particular, were assumed to respond to their females’ hormonal and fecundity phases. We now present experiments with biparental domestic geese (Anser domesticus) kept as pairs to ask whether TC occurs also in these generally polygynous animals. We further ask how different conditions of mate choice affect TC and whether established TC is maintained during a polygynous flock situation. We measured androgen metabolites (AM) non-invasively from individual droppings. In females, AM was related with gonadal activity as it increased after GnRH but not ACTH challenge. Females with preferred partners had higher maximum AM during egg laying and higher rates of initiating incubation than randomly paired females. Domestic ganders had seasonal AM patterns typical for polygynous males. Within-pair TC ranged from almost perfectly positive to non-correlated in domestic geese but mate choice did not explain TC variation. TC of previous pairs was generally reduced in the flock situation, probably confounded by factors of the social environment, i.e. mating opportunity and availability of multiple partners. On top of the underlying reproductive physiology our results suggest two episodic components of TC: a female androgen responsiveness to the preferred partner at least during egg formation, and the male’s facultative potential to respond to her readiness to breed. 相似文献
78.
无创呼吸机治疗呼吸衰竭疗效观察 总被引:4,自引:0,他引:4
目的 探讨双水平无创通气治疗慢性阻塞性肺病合并Ⅱ型呼吸衰竭的临床疗效.方法 106例慢性阻塞性肺病合并Ⅱ型呼吸衰竭的患者,分为对照组和无创呼吸机治疗组.两组患者均给予氧疗、抗感染、祛痰、支气管扩张剂、糖皮质激素、呼吸兴奋剂、纠正水电解质酸碱失衡等常规治疗;无创呼吸机治疗组上述常规治疗基础上加BiPAP无创呼吸机治疗.比较两组治疗前后24h心率、呼吸频率、动脉血气变化.结果 两组患者治疗后临床症状、心率、呼吸频率、动脉血气均较治疗前显著改善,而无创呼吸机治疗组治疗效果显著优于对照组.结论 使用无创呼吸机可有效改善慢性阻塞性肺病合并Ⅱ型呼吸衰竭患者的生命体征及血气,值得临床推广应用. 相似文献
79.
BiPAP治疗慢性阻塞性肺病合并肺性脑病的临床观察 总被引:1,自引:0,他引:1
[目的]探讨无创正压通气(NPPV)对慢性阻塞性肺疾病急性加重(AECOPD)合并肺性脑病的治疗作用。[方法]应用经鼻(面)罩双水平气道正压(BiPAP)呼吸机对40例AECOPD伴肺性脑病患者在常规治疗同时进行无创通气治疗。观察治疗前及治疗后2 h、48 h的动脉血气及临床变化。[结果]40例患者5例死亡,其余患者血气分析及临床症状明显改善,PH值升高(P﹤0.05),PaCO2水平降低(P﹤0.05),PaO2水平升高,病人意识改善。[结论]无创正压通气对AECOPD并肺性脑病患者的疗效肯定。 相似文献
80.
目的探讨血小板计数(PC)、脾脏指数(SI)、血小板计数/脾脏指数(PC/SI)、门静脉宽度(PV)、脾静脉宽度(SV)、门静脉宽度/脾静脉宽度(PV/SV)在预测中重度食管静脉曲张(EV)中的意义。方法测量196例肝硬化患者的PV、SV、脾脏长径(SL)及厚度(ST)(SI=SL×ST)、PC,应用ROC曲线下面积(AUC)的值评价上述非侵入性指标预测中重度EV的准确性。结果PC/S1、PC、PV/SV的AUC分别为0.870、0.781、0.655;PV、SV、SI的AUC不足0.5。PC/SI≤0.97时,预测中重度EV的敏感度为89.4%,特异度为70.6%。结论PC/SI是预测中重度EV较理想的非侵入性指标,当PC/SI〈0.97时,判断中重度EV存在的敏感度、特异度最高。 相似文献