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1.
Our aim was to evaluate the long-term skeletal stability of the mandible in 21 patients after orthognathic surgery with physiological positioning. The measurement points SNB, B point (X, Y), Pog (X, Y), and the angle of the ramus were measured on cephalometric photographs to assess skeletal stability preoperatively, immediately after operation, and one and two years postoperatively. In addition, we evaluated the clinical symptoms of disorders of the temporomandibular joint (TMJ). The analysis of the cephalometric photographs showed that SNB, B point X, and Pog X showed no significant differences among the postoperative time points. On the other hand, B point Y and Pog Y showed no significant differences throughout the study period. We compared the angle of the ramus before operation and two years postoperatively, and no significant difference was found. In addition, no cases showed any pathological symptoms of disorders of the TMJ two years postoperatively. The long-term stability after orthognathic surgery with physiological positioning was confirmed, and it seems to be a reliable orthognathic treatment in patients with mandibular prognathism.  相似文献   
2.
Rotary ventricular assist devices (VADs) are less sensitive to preload than the healthy heart, resulting in inadequate flow regulation in response to changes in patient cardiac demand. Starling‐like physiological controllers (SLCs) have been developed to automatically regulate VAD flow based on ventricular preload. An SLC consists of a cardiac response curve (CRC) which imposes a nonlinear relationship between VAD flow and ventricular preload, and a venous return line (VRL) which determines the return path of the controller. This study investigates the importance of a physiological VRL in SLC of dual rotary blood pumps for biventricular support. Two experiments were conducted on a physical mock circulation loop (MCL); the first compared an SLC with an angled physiological VRL (SLC‐P) against an SLC with a vertical VRL (SLC‐V). The second experiment quantified the benefit of a dynamic VRL, represented by a series of specific VRLs, which could adapt to different circulatory states including changes in pulmonary (PVR) and systemic (SVR) vascular resistance versus a fixed physiological VRL which was calculated at rest. In both sets of experiments, the transient controller responses were evaluated through reductions in preload caused by the removal of fluid from the MCL. The SLC‐P produced no overshoot or oscillations following step changes in preload, whereas SLC‐V produced 0.4 L/min (12.5%) overshoot for both left and right VADs. Additionally, the SLC‐V had increased settling time and reduced controller stability as evidenced by transient controller oscillations. The transient results comparing the specific and standard VRLs demonstrated that specific VRL rise times were improved by between 1.2 and 4.7 s ( = 3.05 s), while specific VRL settling times were improved by between 2.8 and 16.1 seconds ( = 8.38 s) over the standard VRL. This suggests only a minor improvement in controller response time from a dynamic VRL compared to the fixed VRL. These results indicate that the use of a fixed physiologically representative VRL is adequate over a wide variety of physiological conditions.  相似文献   
3.
P-glycoprotein (P-gp), a member of the adenosine triphosphate (ATP)-binding cassette (ABC) family of transporter molecules, is responsible for maintaining low intracellular concentrations of a variety of extracellular compounds and xenobiotics, and for transport of various intracellular molecules. Many drugs are P-gp substrates and intracellular concentrations of these agents may be critical for drug action. Experience in oncology indicates that repeated exposure to P-gp substrate cytotoxic drugs leads to the selection of drug-resistant tumor cells that overexpress P-gp. Since immunosuppressive agents such as cyclosporine, tacrolimus, sirolimus and corticosteroids are substrates for P-gp and since T-cells also express P-gp, it is conceivable that an analogous mechanism exits for therapy-resistant graft rejection. As will be discussed in this article, P-gp may interfere with the response to immunosuppressive therapy through several distinct mechanisms, and as such may represent an attractive therapeutic target.  相似文献   
4.
Summary The influence of tapering on the metabolic and performance parameters in endurance cyclists was investigated. Cyclists (n = 25) trained 5 days · week–1, 60 min·day–1, at 75–85% maximal oxygen consumption (VO2max) for 8 weeks and were then randomly assigned to a taper group: 4D (4 days;n = 7), 8D (8 days;n = 6), CON (control, 4 days rest;n = 6), NOTAPER (non-taper, continued training;n = 6). Muscle biopsy specimens taken before and after training and tapering were analysed for carnitine palmityltransferase (CPT), citrate synthase, ß-hydroxyacyl CoA dehydrogenase (HOAD), cytochrome oxidase (CYTOX), lactate dehydrogenase, glycogen and protein. Significant increases inVO2max (6%), a 60-min endurance cycle test (34.5%), oxidative enzymes (77–178%), glycogen (35%) and protein (34%) occurred following training. After the taper, HOAD and CPT decreased 25 % (P<0.05) and 26% respectively, in the CON. Post-taper CYTOX values were different (P<0.05) for 4D and 8D compared with CON. Muscle glycogen levels were increased (P<0.05) after tapering in the 4D, 8D and CON, but decreased in NOTAPER. Similarly, power output at ventilation threshold was significantly increased in the 4D (27.4 W) and 8D (27 W) groups, but decreased (22 W) in the NOTAPER. These findings suggest that tapering elicited a physiological adaptation by altering oxidative enzymes and muscle glycogen levels. Such an adaptation may influence endurance cycling during a laboratory performance test.  相似文献   
5.
目的:探讨施地瑞玛生理性海水鼻腔喷雾器治疗小儿干燥性鼻炎的疗效。方法:将58例患儿随机分成2组,2组均不使用其他药物。治疗组给予施地瑞玛生理性海水鼻腔喷雾器喷鼻;对照组给予生理性盐水滴鼻液滴鼻,观察2组治疗前后症状、体征及有效率。结果:根据2组的主要症状、体征及疗效,治疗组优于对照组(P<0.05)。结论:生理性海水鼻腔喷雾器治疗小儿干燥性鼻炎,可以缩短病程,改善鼻腔功能,疗效确切,且使用安全、舒适、方便,可以作为治疗小儿干燥性鼻炎的理想药物。  相似文献   
6.
更年期妇女生理心理健康状况探讨   总被引:26,自引:2,他引:24  
目的探讨更年期妇女生理、心理健康状况及相互关系 ,为进一步缓解更年期妇女的症状提供医疗和护理上的依据。方法对北京大学第一临床医院更年期门诊病人进行问卷调查 ,数据结果应用SPSS 8 0数据分析软件包进行处理。结果更年期妇女Kupperman总体平均分为 2 0 12± 9 97分 ,SCL 90评分量表总体平均分为 4 6 6 2±36 2 8分 ,并且以潮热出汗、失眠等躯体症状 ,以及强迫症状、人际关系敏感、抑郁、焦虑等心理症状表现突出。应用激素替代疗法后 ,能有效缓解更年期妇女潮热出汗、抑郁心烦、疲乏、骨关节痛、敌对的症状 ,与未用激素替代疗法者有显著差异。对更年期妇女的生理、心理进行分析显示 ,更年期妇女生理心理症状呈中等程度相关性 (r=0 6 17,P <0 0 0 1)。结论医护人员应加强对更年期妇女生理心理双方面的关注。  相似文献   
7.
用强迫接触法对微小按蚊进行选育,溴氰菊酯浓度为0.1mg/m~2,选育温度26℃,触药24h后的死亡率至少不低于20%。在选育过程中,对选育蚊的生理活动、繁殖特性等进行动态观察。该蚊长期接触低剂量溴氰菊酯后,并不影响其体重,吸血及寿命:但随选育代数的增加,产卵量减少,孵化率下降,致死力增加。成蚊前期历期时间延长,净增殖力、内禀增长力、增殖有限速率都有所下降。这些因素都可影响后代成活蚊的种群繁殖力。  相似文献   
8.
目的研究心理训练对高特质焦虑新兵考核时生理指标和成绩的影响。方法采用个人评价问卷(PEI)、状态.特质焦虑问卷(STAI)和简易应对方式问卷对参加考核的新兵实施团体测试。将被试者分为对照组、低特质焦虑组、高特质焦虑组和干预组,对干预组进行自我评价、潜能开发、团队精神强化、应对方式的心理训练。测试考核前后生理指标差值及考核成绩的变化。结果干预组新兵军事考核前后收缩压、舒张压和脉搏三项生理差值与考核成绩明显优于高特质焦虑组(P〈0.05)。结论系统的心理训练可有效改善新兵对应激情景的生理和心理反应,提高作业绩效。  相似文献   
9.
Two ways of rate control for diaphragm pacing are proposed. One is rate control using only the patients' body temperature (method I). The other is rate control by both the patients' heart rate and body temperature (method II). To test the effectiveness of these methods, a diaphragm pacemaker which can be controlled by both heart rate and body temperature has been developed. It was applied to nine mongrel dogs. The pacing rate is controlled by atrial blood temperature (method I) or by both heart rate and temperature (method II). The animal's metabolism was elevated by the administration of a pyrogenic drug. It was found that method I is not suited to rapid changes in metabolism; however, it is useful in extreme metabolic elevation. An animal's metabolism was supported by using method II in all ranges of metabolism. This method proved more effective than method I for rate-responsive diaphragm pacing.  相似文献   
10.
Previous literature presents discordant results on the relationship between physiological and subjective sexual arousal in women. In this study, the use of hierarchical linear modeling (HLM) revealed a significant concordance between continuous measures of physiological and subjective sexual arousal as assessed during exposure to erotic stimuli in a laboratory setting. We propose that past studies that have found little or no association between the two measures may have been in part limited by the methodology and statistical analyses employed.  相似文献   
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