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51.
目的我们应用平衡法门控心血池显像技术对不同Killip分级的前壁心肌梗死患者进行左室总体和局部收缩和舒张功能参数的对比分析。方法对照组15例(G0),前壁心肌梗死KillipⅠ级17例(G1),前壁心肌梗死KillipⅡⅢ级12例(G2)。利用平衡法门控心血池显像技术评价3组的左室总体和局部的收缩与舒张功能。结果①左室整体收缩功能,在LVEF,ESC 2个参数中,G1比G0有显著差异(P<0.05),G2分别比G1和G0有显著差异(P<0.05)。在PER、1/3EF、1/3ER 3个参数中,G2分别比G1和G0显著下降(P<0.05)。②左室总体舒张功能,在PFR、1/3FF、1/3FR、EDC中,G1比G0有显著差异(P<0.05),G2分别比G1和G0有显著差异(P<0.05)。③左室局部收缩功能,在以LVREF为参数时,G1在4个节段比G0显著差异(P<0.05),G2在所有6个节段中比G1和G0均显著下降(P<0.05)。④左室局部舒张功能,在以LVR1/3FF为参数时,G1在4个节段比G0显著下降(P<0.05),G2在所有6个节段比G0和G1均显著下降(P<0.05)。结论前壁心肌梗死后出现心功能受损或心力衰竭的主要原因为左室重构。  相似文献   
52.
53.
目的观察鼻窦内镜术(endoscopic sinu ssurgery,ESS)对慢性鼻窦炎伴支气管哮喘患者哮喘发作的影响。方法对210例慢性鼻窦炎患者施行ESS术,其中伴有支气管哮喘病史者42例(20.0%)。210例患者均于术前、术后采用酶联免疫吸附测定法(ELISA)检测外周血单个核细胞(PBMC)培养上清液中的白细胞介素4(IL-4),干扰素γ(IFN-γ),可溶性白细胞介素2受体(sIL-2R)和可溶性IgE低亲和力受体(solube CD23,sCD23)的含量,并与20例正常对照组进行比较。通过主观和客观标准评定42例患者哮喘发作及对皮质类固醇的耐受状况,并对术后患者进行为期1年(10例)和3年(32例)的随访。结果鼻窦炎合并支气管哮喘患者术前PBMC培养上清液中IL-4,sIL-2R、sCD23含量较对照组显著升高,而IFN-γ含量较对照组显著减少。术后IL-4、sIL-2R、sCD23含量较对照组显著降低,而IFN-γ含量显著增高。术后哮喘改善水平由随访术后1年的45%提高到术后3年的70%。42例中32例(76%)哮喘发作次数明显减少,术前长期服用类固醇的2l例中,14例(67%)减少了对口服类固醇的使用。结论ESS对慢性鼻窦炎伴支气管哮喘患者的治疗有较满意的远期疗效。ESS能调节IL-4、IFN-γ sIL-2R、sCD23水平,降低哮喘的发作频率和对类固醇的依赖。  相似文献   
54.

Background  

Liver transplantation in presence of diffuse portal vein thrombosis is possible by using caval blood as portal inflow, through cavo-portal transposition. However, clinical results are heterogeneous and experimental studies are needed, but similar hemodynamic conditions are difficult to obtain, especially in small animals. Herein we describe a new simple model of cavo-portal transposition in rat.  相似文献   
55.
随着人们生活水平的日益提高,对美的要求也越来越高。牙齿美自治疗经历了氧化物温热外漂白法、家庭漂白法、激光漂白法、树脂贴面、烤瓷牙修复等过程。但它们都不同程度地存在美白效果不理想、稳定性差或对牙齿有损害等缺点。Beyond冷光美白法由于其使用安全,美白效果显著,操作时间短,成为牙齿美自治疗新宠^[1]。[第一段]  相似文献   
56.
OBJECTIVES: The aim of this study was to evaluate the safety and effectiveness of laparoscopic-assisted sigmoid colectomy for diverticulitis and to assess its postoperative advantages. METHODS: From 1999 to 2001, 5 patients were selectively operated on with a laparoscopic-assisted procedure for uncomplicated sigmoid diverticulitis. In the preceding period (September 1997 through December 1998), 4 patients underwent open procedures for the same pathology. The surgical indication with the same criteria was restrictive: at least 2 acute episodes had occurred that were treated with hospital admission and that were separated by an adequate period (2 months) of medical therapy. RESULTS: No conversions of laparoscopy to an open procedure were necessary. Age, sex, weight, morbidity, and mortality were similar between the 2 groups. Operative time was 180 minutes for laparoscopy and 120 minutes for laparotomy. Postoperative resumption of peristalsis was 24 hours versus 4 days, resumption of alimentation was on the second postoperative day versus the fifth postoperative day, and hospital stay was 7 days versus 12 days for laparoscopy and laparotomy, respectively. CONCLUSION: This study shows the feasibility and the advantages of elective laparoscopic-assisted colonic resection for uncomplicated sigmoid diverticulitis. The advantages of the laparoscopic approach are the lower need for analgesics and the more precocious ambulation, canalization, resumption of alimentation, and the shorter hospital stay.  相似文献   
57.
Preparation of blood specimens is a major bottleneck in the laboratory throughput. Reliable strategies for reducing the time required for specimen processing without affecting quality should be acknowledged, especially for laboratories performing stat analyses. The present investigation was planned to establish a minimal suitable centrifuge time for primary samples collected for routine coagulation testing. Five sequential primary vacuum tubes containing 0.109 mol/l buffered trisodium citrate were collected from 10 volunteers and were immediately centrifuged on a conventional centrifuge at 1500 x g, at room temperature for 1, 2, 5, 10 and 15 min, respectively. Hematological and routine coagulation testing, including prothrombin time, activated partial thromboplastin time and fibrinogen, were performed. The centrifugation time was inversely associated with residual blood cell elements in plasma, especially platelets. Statistically significant variations from the reference 15-min centrifuge specimens were observed for fibrinogen in samples centrifuged for 5 min at most and for the activated partial thromboplastin time in samples centrifuged for 2 min at most. Meaningful biases related to the desirable bias were observed for fibrinogen in samples centrifuged for 2 min at most, and for the activated partial thromboplastin time in samples centrifuged for 1 min at most. According to our experimental conditions, a 5-10 min centrifuge time at 1500 x g may be suitable for primary tubes collected for routine coagulation testing.  相似文献   
58.
We examined the clinical and radiographic results of 93 patients affected by knee arthritis or osteonecrosis subjected to unilateral cementless mobile-bearing total knee arthroplasty with the LCS prothesis (Depuy/Johnson & Johnson). The mean follow-up was 9.5 years (range, 7–12 years). Clinical evaluation was performed using the Knee Society rating system, while radiographic evaluation was done according to the Knee Society roentgenographic system. At the latest follow-up, the mean knee score was 87 points: the functional score improved from 40 to 90. Radiolucent lines were small and not progressive. The implant survival at 12 years was 88%. Six knees (7%) required revision for implant-related problems. We conclude that the mobile-bearing prosthesis is a successful device even at long-term follow-up.  相似文献   
59.
Background: Recent reports indicate increased incidence of Clostridium botulinum infections, particularly among drug abusers and tissue allograft recipients. Botulinum toxin also has potential application in biochemical warfare. The neurotoxin-induced paralysis often requires mechanical ventilation with and without muscle relaxants. The authors investigated the long-term effects of botulinum toxin on muscle function, expression of nicotinic acetylcholine receptors (nAChRs), and their interaction with muscle relaxant, atracurium.

Methods: Rats (n = 30) were injected with varying doses (0.625, 2.5, and 10 U) of botulinum toxin into the tibialis muscle. Control animals (n = 9) received an equivalent volume of saline. At 128 days after injection, neuromuscular function, pharmacodynamics of atracurium, and nAChRs were evaluated.

Results: Nerve-evoked tensions, including tetanic tension and muscle mass, were decreased on the toxin-injected side in a dose-dependent manner relative to saline-injected controls as well as the contralateral side. Specific muscle tension and specific tetanic muscle tension (tensions/muscle mass) were not reduced. The ED10 of atracurium was reduced, the ED50 was unchanged, and the ED90 was increased in the highest (10-U) dose of toxin group. The atracurium plasma concentration to maintain a steady state 50% paralysis was significantly reduced in the 10-U toxin group. The nAChR concentrations in the tibialis muscle were significantly increased in a dose-dependent manner in all experimental groups.  相似文献   

60.
目的 通过病例对照研究 ,了解中国老年人群血管内皮型一氧化氮合酶 (eNOS)基因目的 通过病例对照研究 ,了解中国老年人群血管内皮型一氧化氮合酶 (eNOS)基因Glu2 98Asp多态性的分布 ,分别探讨其与老年脑梗死及血脂以及一氧化氮等脑梗死危险因素的关系。 方法对门诊及住院中确诊的 4 0例老年脑梗死和 16 9例性别、年龄相匹配的老人 ,测量他们的身高、体重及座位血压 ,并测定他们的空腹血脂、空腹血糖 (FBS)及一氧化氮 (NO)等 ,应用聚合酶链反应 (PCR)和限制性片断长度多态性 (RFLP)检测eNOS基因Glu2 98Asp多态性。结果 脑梗死和对照组eNOS基因Glu2 98Asp多态性构成有显著性差异 (χ2 =4 31,P =0 0 38) ,脑梗死组Glu/Asp基因型高于对照组(32 5 %vs 17 8% ) ;脑梗死组 2 98Asp等位基因频率高于对照组 (16 2 5 %vs 8 9% ) ,但是两组等位基因频率的分布比较 ,没有显著性差异 (χ2 =3 81,P =0 0 5 1)。结论 eNOS基因Glu2 98Asp多态性在中国老年人群中存在 ,并且基因...  相似文献   
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