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51.
应用二维超声方法评价高血压血管内皮功能   总被引:1,自引:1,他引:1  
目的:对高血压1~2级无心血管其他危险因素病人的血管内皮功能作一评估,并探讨高血压对内皮功能的影响及其可能机制。方法:研究对象30例,高血压病人和正常人各15例。应用高分辨二维超声方法检测反应性充血前后肱动脉直径,比较两组的血流介导血管舒张测定百分数(FMD)功能以及与血压之间的关系;同时比较两组血清氧化低密度脂蛋白(ox-LDL)、一氧化氮(NO)及内皮素-1(ET-1)的水平。结果:①高血压病人FMD(10.79%)明显低于对照组(19.61%),P<0.01。②相关分析显示,FMD%分别与收缩压(r=-0.446,P<0.01)、舒张压(r=-0.645,P<0.01)呈负相关。③高血压病人血清ox-LDL、ET-1显著高于对照组(P<0.01),而NO则明显低于对照组(P<0.01)。结论:高血压病早期虽无明显动脉硬化,但已存在血管内皮功能的损伤。  相似文献   
52.
目的探讨复方甘草酸苷注射液联合局部浸润治疗老年带状疱疹后神经痛(PHN)的临床效果及其对免疫功能的影响。方法老年PHN20例,静脉滴注复方甘草酸苷40mg(5%葡萄糖注射液250ml),1次/d,连续3周为1个疗程,同时口服复方甘草酸苷片50mg,3次/d;以0·2%布比卡因20ml(含加入醋酸泼尼松龙30mg、利巴韦林0·4g,弥可保1mg)在皮损疼痛区皮下浸润,2次/d。以VAS评分法评价治疗前后的临床效果;检测治疗前和治疗后7、14、21d外周血淋巴细胞亚群变化。结果治疗后VAS评分显著降低(P<0·01);治疗后CD3 、CD4 、CD4 /CD8显著回升(P<0·01),并接近正常水平。结论老年PHN免疫功能可受到不同程度抑制,采用复方甘草酸苷联合皮损区局部浸润对缓解PHN患者的神经病理性疼痛有显著效果,并有提高及调节免疫功能的作用。  相似文献   
53.
陆茂  彭科  宋黎  沈跃丽 《西部医学》2011,23(10):1877-1878
目的观察小切口皮下剥离联合打包治疗腋臭的疗效及并发症。方法将68例腋臭患者随机分为联合治疗组和单纯皮下剥离组,观察两组的疗效和并发症。结果两组总有效率比较差异无统计学意义(P〉0.05),联合治疗组并发症发生率明显低于单纯皮下剥离组(P〈0.05)。结论小切口皮下剥离联合打包治疗腋臭疗效确切,并发症发生率低,可在临床推广应用。  相似文献   
54.
Trazodone is approved for the treatment of major depressive disorders, marketed as immediate release (IR), prolonged release, and once a day (OAD) formulation. The different formulations allow different administration schedules and may be useful to facilitate patients’ compliance to the antidepressant treatment. A previously verified physiologically‐based pharmacokinetic model based on in vitro and in vivo information on trazodone pharmacokinetics was applied, aiming at predicting brain receptor occupancy (RO) after single and repeated dosing of the IR formulation and repeated dosing of the OAD formulation in healthy subjects. Receptors included in the simulations were selected using static calculations of RO based on the maximum unbound brain concentration (Cmax,brain,u) of trazodone for each formulation and dosing scheme, resulting in 16 receptors being simulated. Seven receptors were simulated for the IR low dose formulation (30 mg), with similar t onset and duration of coverage (range: 0.09–0.25 h and 2.1–>24 h, respectively) as well as RO (range: 0.64–0.92) predicted between day 1 and day 7 of dosing. The 16 receptors evaluated for the OAD formulation (300 mg) showed high RO (range: 0.97–0.84 for the receptors also covered by the IR formulation and 0.73–0.48 for the remaining) correlating with affinity and similar duration of time above the target threshold to the IR formulation (range: 2–>24 h). The dose‐dependent receptor coverage supports the multimodal activity of trazodone, which may further contribute to its fast antidepressant action and effectiveness in controlling different symptoms in depressed patients.

Study Highlights
  • WHAT IS THE CURRENT KNOWLEDGE ON THE TOPIC?
The antidepressant efficacy of trazodone has been shown to be significantly correlated to its steady‐state plasma levels, and previous work has shown some understanding of trazodone range of affinity for different receptors, at different doses, but without considering the different available formulations. Trazodone is commonly available as: immediate release (IR), prolonged release (PR), and once a day (OAD) tablets. The IR formulation has a rapid onset and short duration of action, whereas the PR formulation is characterized by an absorption boost as soon as it is administered and has a comparatively delayed maximum concentration (Cmax). Conversely, the OAD formulation provides a controlled release of trazodone over 24 h without the early high peak plasma concentration seen with the IR and PR formulations.
  • WHAT QUESTION DID THIS STUDY ADDRESS?
This work aims to identify the brain receptors reaching a threshold occupancy of 50% through static predictions and determine the occupancy versus time profile for those of interest following administration of short‐ and long‐acting trazodone formulations.
  • WHAT DOES THIS STUDY ADD TO OUR KNOWLEDGE?
Brain receptor occupancy (RO) for key targets were predicted based on free drug concentrations, allowing for a physiologically relevant assessment of the different pathways affected by each formulation and dose.
  • HOW MIGHT THIS CHANGE CLINICAL PHARMACOLOGY OR TRANSLATIONAL SCIENCE?
The presented physiologically‐based pharmacokinetic approach to assess RO can be used to guide formulation selection and dosing in clinical studies.  相似文献   
55.
To determine the relationship of coxsackievirus A16 (CA16) to prototype CA16-G10, we conducted a phylogenetic analysis of circulating CA16 strains in China. Complex recombinant forms of CA16-related viruses involving multiple human enteroviruses, subgroup A (CA4, CA16, and enterovirus 71), are prevalent among patients with hand, foot, and mouth disease.  相似文献   
56.
ContextValerian extract capsule (VEC) is an effective Chinese patent medicine used for gastrointestinal (GI) diseases.ObjectiveTo investigate the detailed pharmacological activity for VEC clinical effects in GI diseases.Materials and methodsSprague-Dawley rats were divided into six groups: control, model, and drug-treated (VEC-L, VEC-M, VEC-H, and teprenone). Rats were orally administered VEC (124, 248, 496 mg/kg) and teprenone (21.43 mg/kg) for 3 consecutive days. After 1 h, the five groups (except the control group) were orally given ethanol (10 mL/kg) for 1 h or indomethacin (80 mg/kg) for 7 h. The spasmolytic activity of VEC (0.01–1 mg/mL) on ACh/BaCl2-induced New Zealand rabbit smooth muscle contraction was performed. The C57BL/6 mice carbon propelling test evaluated the effects of VEC (248–992 mg/kg) on intestinal motility in normal and neostigmine/adrenaline-induced mice.ResultsCompared with the model group, VEC treatment reduced the gastric lesion index and mucosal damage. Further experiments showed that the pathological ameliorative effect of VEC was accompanied by augmentation of the enzymatic antioxidant system and cytoprotective marker (COX-1, p < 0.01; PGI2 p < 0.05;), along with the alleviation of the levels of MPO (ethanol: 15.56 ± 0.82 vs. 12.15 ± 2.60, p < 0.01; indomethacin: 9.65 ± 3.06 vs. 6.36 ± 2.43, p < 0.05), MDA (ethanol: 1.66 ± 0.44 vs. 0.81 ± 0.58, p < 0.01; indomethacin: 1.71 ± 0.87 vs. 1.09 ± 0.43, p < 0.05), and inflammatory mediators. VEC decreased the high tone induced by ACh/BaCl2 and promoted intestinal transit in normal and neostigmine/adrenaline-induced mice.Discussion and conclusionsVEC showed a potential gastroprotective effect, suggesting that VEC is a promising phytomedicine for the treatment of GI diseases.  相似文献   
57.
介绍了国内、国际有源植入物分技术委员会及有源植入式医疗器械标准的现状.结合日常检测和具体实例,对现行标准中标记要求、包装要求和混合医疗相关要求等进行了总结和论述,有助于正确理解标准要求,并为该类医疗器械的研发、检验和评审等提供了思路和参考,保障了医患的用械安全.  相似文献   
58.
BackgroundRadical nephroureterectomy (RNU) is the principal method for treatment of high-risk upper urinary tract urothelial carcinoma (UTUC). The transperitoneal approach is associated with poor disease progression, but the distal ureter-bladder cuff (DUBC) resection through retroperitoneal laparoscopic approach is difficult. This study proposed a modulated RNU technique, namely, total retroperitoneal laparoscopic radical nephroureterectomy (tRLRNU), with its advantages of DUBC resection and requiring fewer trocars etc. The efficiency, safety, and short-term impacts were retrospectively compared with total transperitoneal laparoscopic radical nephroureterectomy (tTLRNU).MethodsTotal of 12 patients who received tRLRNU and 28 patients who received tTLRNU were enrolled. The choice of surgical approach was random and their data were retrospectively analyzed. During tRLRNU, the laparoscope was versed towards the caudal direction and a retroperitoneal laparoscopic ureterectomy was performed. The bladder cuff was entirely transected and the bladder incision was sutured. The tRLRNU cases were compared with the tTLRNU cases in terms of general clinical data, pathologic parameters, peri-operative parameters, adjuvant therapy, and short-term outcomes. The independent samples t-tests, chi-square tests, and Fischer exact tests were used to analyze the differences.ResultsThere were no significant differences in the basic patient characteristics between the 2 groups. The data were comparable. There were significantly fewer trocars utilized in tRLRNU group compared to tTLRNU group (P=0.0008). tRLRNU group experienced less blood loss (98.33±61.32 versus 170.71±121.32 mL; P=0.017), smaller drainage volume (182.08±163.60 versus 1,924.82±3,370.02 mL; P=0.011), and shorter extubation time (5.67±1.07 versus 8.57±6.96 days; P=0.040) compared to tRLRNU group. There were no statistically differences in the other peri-operative parameters, including whole operation time, transfusion, visceral and vascular injuries, open conversion, post-operative bleeding, recovery time of intestinal function, and discharge time. The patient outcomes in tTLRNU group at 6 months were significantly worse than that of tRLRNU group by comparing progression-free survival, progression survival and mortality (P=0.039).ConclusionsThe tRLRNU was potentially safer, minimally invasive, and more effective compared to the tTLRNU. Due to the small sample size, short follow-up time and no randomization of the study, future comparative studies are warranted to further analyze long-term outcomes of tRLRNU.  相似文献   
59.
1 引言 在对事物的结果没有十分把握的情况下,进行活动会带来风险,其后果可能与预期结果不一致.而对一个患者健康状况方面的任何影响,都难免带来不良后果的风险,因为患者在现有的医疗条什下和特殊治疗中本来就有一定风险.  相似文献   
60.
This paper focuses on the effect of gear steel on distortion due to phase transformation in carburizing and quenching. The carburizing and quenching process of C-rings under suspension was studied by using the finite element method based on the thermo-mechanical theory, considering phase transformation. The phase transformation kinetics parameters, depending on different carbon contents, were measured by Gleeble-3500. The distortion behavior of the carburized C-ring during the cooling stage was analyzed, as well as the carbon concentration distribution and martensite volume fractions. The accuracy of the simulation was also verified by comparing the experimental data with the simulated result of the distortion and microstructure. A reliable basis is provided for predicting the distortion mechanism of gear steels in carburizing and quenching.  相似文献   
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