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991.
徐强 《右江民族医学院学报》2000,22(4):527-529
为了解QTcd、JTcd在心电图活动平板运动试验结果判断中的价值 ,对 10 0例活动平板运动试验阳性者及 80例阴性者运动前后的心电图QTcd、JTcd进行对比观察。结果表明 :运动前两组QTcd、JTcd差异均无显著性 ( P〉0 .0 5 ) ;运动后 2min运动试验阳性组与阴性组比较 ,QTcd、JTcd差异有高度显著性 (P <0 .0 1) ;阳性组运动试验后 2minQTcd、JTcd均较运动前显著延长 ( P <0 .0 1) ;阴性组运动后 2minQTcd、JTcd与运动前比较差异无显著性 ( P >0 .0 5 )。认为运动试验后QTcd、JTcd延长可作为判断运动试验结果的指标。 相似文献
992.
Objective. Angiotensin-converting enzyme (ACE) plays a key role in the metabolism of angiotensin Ⅱ (AT Ⅱ) and inactivation of bradykinins and tachykinins, which are potent bronchialconstrictors and mediators of inflammation asthma, and ACE is heavily expressed in the lungs. An insertion-deletion (D/I) polymorphism of ACE gene has been shown to be associated with levels of ACE. We investigate whether the polymorphism of ACE gene is associated with asthma and bronchial responsiveness.Methods. A case-control study was carried out in 50 asthmatics, 7 families with at least 2 asthmatic individuals, and 50 healthy subjects. The insertion/deletion (I/D) polymorphism of ACE gene was amplified by polymerase chain reaction (PCR). Methacholine brocho-provocation and pulmonary function tests were performed in all asthmatics. Results. There was an higher gene frequency of DD genotype of ACE gene in asthmatic subjects and families individuals compared with healthy subjects (46%, 53% vs 16%, P<0.05; odd ratio 4.98). Anhigher prevalence of DD genotype of ACE was in patients with bronchial hyperresposiveness (BHR) (67%vs 33%, P<0.05; odd ratio 3.8). Accordingly, the mean values of FEV1% and FEV1/FVC were higher in asthmatics carrying non-DD alleles than patients with DD genotype (73.78% vs 56.56%, P<0.05; 79.19% vs 69.29%, P<0.05, respectively).Conclusion. These results suggested that DD allele of ACE genotype was significantly involved in genetic susceptibility to asthma. DD genotype of ACE might be a risk factor for the degree of airway obstruction, it could also be implicated in pathogenesis of bronchial hyperresponsiveness. 相似文献
993.
旅游区院前急救模式探讨 总被引:1,自引:0,他引:1
目的:探讨旅游区院前急救模式。方法:对266例院急救病例进行分类处理。结果:占前三位疾病是外伤、中毒、心脑血管疾病,除8例死亡外,全部转送院内诊治。结论:院前急救是急诊医学的关键环节,关系到院内进一步急救的抢救成功率。 相似文献
994.
<正>特洛细胞(telocytes,TCs)是一种新发现的间充质来源的间质细胞,形态结构具有特异性和多样性,目前认为TCs可能对维持组织稳态和损伤修复有潜在的作用,参与不同疾病的发生发展[1]。TCs于2005年被L.M. Popescu教授等[2]在电镜下发现,认为其与Cajal间质细胞(interstitial cells of Cajal,ICCs)结构类似,遂将其命名为Cajal样间质细胞(interstitial Cajallike cells,ICLCs)。随着显微镜技术的发展及对TCs的深入研究,人们发现此类细胞与ICCs在分子标记上存在明显不同, 相似文献
995.
目的 探究Chevron截骨术截骨远端外侧位移距离对外翻足关节接触特征的影响,为临床上选择合适的位移距离提供参考依据。方法 测量踝关节中立位状态下正常足、外翻足及外翻足Chevron截骨术截骨远端分别向外侧位移2.0、4.0、6.0 mm后前足、中足和后足各关节接触力、峰值压强和接触面积,并对结果进行分析。结果 与正常足相比,外翻足第1跖楔关节(t=-3.33, P=0.02)、跟骰关节(t=-2.74, P=0.03)和距下关节(后关节面)(t=-2.89, P=0.03)的接触力显著增高;外翻足距舟关节(t=-2.73, P=0.03)与跟骰关节(t=-2.74, P=0.03)的峰值压强显著增高;行Chevron截骨术后,随着截骨远端向外侧位移距离的增加,外翻足第1跖楔关节和跟骰关节的接触力逐渐减小;外翻足距舟关节和跟骰关节的峰值压强逐渐减小。结论 中度外翻足行Chevron截骨术后,当第1跖骨截骨远端向外侧位移6 mm时能有效恢复部分关节间力的分布,且能缓解部分关节局部应力集中现象。 相似文献
996.
Mixed plastic waste recycling represents a significant challenge as the phase separation of different components dictates downgraded performance. Polymer-based compatibilizers can offer a promising solution to address this issue, through effectively reducing surface tension and increasing interfacial strength between distinct components to result in improved mechanical and thermal properties of recycled products. This perspective provides an overview of the fundamental concepts for the rational design of copolymer blend compatibilizers and discusses their recent advances, including both preformed and in situ generated systems. Impacts of key material parameters of compatibilizers, such as chain topology, chemical composition, and block sequence on their performance of remediating mixed plastics are discussed. Additionally, reactive compatibilization strategies are also introduced, including in situ formation of polymers, installing functional groups on mixed plastics, and employing dual compatibilization strategies. Looking forward, there are many research and technology opportunities in this area, especially for enabling the use of blend compatibilizers to practically address mixed plastic wastes at scale. Specifically, future compatibilizer design and application should provide strong competitiveness in both cost and energy savings, and carbon emission reduction. Together, the development of blend compatibilizers is an important step in establishing plastic circular economy and creating a more sustainable future. 相似文献
997.
Zahid Hussain Saima Rani Fanshu Ma Wenjing Li Wenqi Shen Tian Gao Jine Wang Renjun Pei 《Reviews in medical virology》2023,33(2):e2425
Dengue illness can range from mild illness to life-threatening haemorrhage. It is an Aedes-borne infectious disease caused by the dengue virus, which has four serotypes. Each serotype acts as an independent infectious agent. The antibodies against one serotype confer homotypic immunity but temporary protection against heterotypic infection. Dengue has become a growing health concern for up to one third of the world's population. Currently, there is no potent anti-dengue medicine, and treatment for severe dengue relies on intravenous fluid management and pain medications. The burden of dengue dramatically increases despite advances in vector control measures. These factors underscore the need for a vaccine. Various dengue vaccine strategies have been demonstrated, that is, live attenuated vaccine, inactivated vaccine, DNA vaccine, subunit vaccine, and viral-vector vaccines, some of which are at the stage of clinical testing. Unfortunately, the forefront candidate vaccine is less than satisfactory, and its performance depends on serostatus and age factors. The lessons from clinical studies depicted ambiguity concerning the efficacy of dengue vaccine. Our study highlighted that viral structural heterogeneity, epitope accessibility, autoimmune complications, genetic variants, genetic diversities, antigen competition, virulence variation, host-pathogen specific interaction, antibody-dependent enhancement, cross-reactive immunity among Flaviviruses, and host-susceptibility determinants not only influence infection outcomes but also hampered successful vaccine development. This review integrates dengue determinants allocated necessities and challenges, which would provide insight for universal dengue vaccine development. 相似文献
998.
999.
- The aim of the present study was to determine the cellular mechanims and potential mediators involved in hypoxic dilatation of porcine small coronary arteries.
- Small coronary arteries were isolated from a branch of the left anterior descending artery of porcine hearts, cannulated with glass micropipettes and studied in a perfusion myograph system. At a transmural pressure of 40 mmHg, the arteries had an internal diameter of 167.8±6.6 μm (n=37).
- In arteries contracted with acetylcholine (ACh), hypoxia (0% O2, 30 min) caused dilatation (86.9±6.7% relaxation, n=6) in vessels with endothelium but constriction in endothelium-denuded vessels.
- Hypoxic vasodilatation occurring in arteries with endothelium was abolished by the KATP channel inhibitor, glibenclamide (0.44 μM), but was not affected by inhibition of nitric oxide synthase (L-NAME, 44 μM) or cyclo-oxygenase (indomethacin, 4.4 μM).
- Bradykinin evoked endothelium-dependent relaxation that was inhibited by L-NAME (44 μM) but not glibenclamide 0.44 μM). Cromakalim (0.1–0.3 μM), a KATP channel opener, caused relaxation that was inhibited by glibenclamide, but was not affected by L-NAME (44 μM) and/or indomethacin (4.4 μM).
- Endothelium-removal inhibited vasodilatation evoked by cromakalim, but increased vasodilator responses to the NO donor, SIN-1 (10−8 to 10−5 M).
- These results indicate that hypoxia acted directly on vascular smooth muscle of small coronary arteries to cause contraction. However, this effect was overwhelmed by endothelium-dependent relaxation in response to hypoxia. This relaxation was most likely mediated by release of an endothelium-derived factor, distinct from nitric oxide or prostacyclin, that activated smooth muscle KATP-channels.
1000.
Plant foods and colon cancer: an assessment of specific foods and their related nutrients (United States) 总被引:3,自引:0,他引:3
Martha L. Slattery John D. Potter Ashley Coates Khe-Ni Ma T. Dennis Berry Debra M. Duncan Bette J. Caan 《Cancer causes & control : CCC》1997,8(5):575-590
Plant foods have been associated inversely with colon cancer. Since amajor focus of this study was to identify components of plant foods whichmay account for their association with colon cancer, nutrients which arecommonly found in plant foods also were evaluated. A population-basedcase-control study was conducted in Northern California, Utah, and the TwinCities area of Minnesota (United States). Complete data were available frominterviewer-administered questionnaires on 1,993 cases and 2,410 controls.Higher intakes of vegetables (for highest relative to lowest quintile ofintake) were associated inversely with colon cancer risk: the odds ratio(OR) was 0.7 for both men (95 percent [CI] confidence interval = 0.5-0.9)and women (CI = 0.5-1.0). Associations were stronger among those withproximal tumors. Total fruit intake was not associated with colon cancerrisk although, among men, higher levels of whole grain intake wereassociated with a decreased risk (OR = 0.6, CI = 0.4-0.9 for older men);high intakes of refined grains were associated with an increased risk (OR =1.5, CI = 1.1-2.1). Dietary fiber intake was associated with a decreasedrisk of colon cancer: OR = 0.5 (CI = 0.3-0.9) for older men; OR = 0.7 (CI =0.4-1.2) for older women; OR = 0.6 (CI = 0.4-1.0) for men with proximaltumors; OR = 0.5 (CI = 0.3-0.9) for women with proximal tumors. Othernutrients, for which plant foods were the major contributor - such asvitamin B6, thiamin, and niacin (women only) - also were associatedinversely with colon cancer. Neither beta-carotene nor vitamin C wasprotective for colon cancer. Adjustment of plant foods for nutrients foundin plant foods or for supplement use did not appreciably alter the observedassociations between plant foods and colon cancer. 相似文献