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61.
The objective of this study was to assess the effects of ascorbic acid supplementation, 500 mg twice daily in the treatment of pressure ulcers as an adjunct to standardized treatment.

The design consisted of a multicenter blinded randomized trial. The control group received 10 mg of ascorbic acid twice daily.

Patients from 11 nursing homes and 1 hospital participated.

Main outcome measures included wound survival, healing rates of wound surfaces, and clinimetric changes over 12 weeks.

Eighty-eight patients were randomized. Intention-to-treat analysis showed that the wound closure probability per unit time (i.e., the closure rate) was not higher in the intervention group than in the control group (Cox hazard ratio of 0.78 [90% precision interval, 0.44–1.39]). Mean absolute healing rates were 0.21 and 0.27 cm2/week in the intervention and control group, respectively (PI of the adjusted difference: −0.17 to 0.13). Relative healing rates and healing velocities did not show favorable results of ascorbic acid supplementation, either. A panel scored slides of the ulcers with a report mark between 1 (bad) and 10 (excellent). The improvement was 0.45 and 0.72 points per week in the intervention and control group, respectively (PI of the adjusted difference: −0.50 to 0.20). With another clinimetric index we could not show any differences, either.

These data do not support the idea that ascorbic acid supplementation (500 vs. 10 mg twice daily) speeds up the healing of pressure ulcers.  相似文献   

62.
目的:研究雌激素对左心室舒张功能的影响。材料和方法:利用多谱勒超声心动图记录了25例健康绝经后妇女二尖瓣口血流频谱,其中15例为雌激素替代治疗组,10例为对照组。所测参数有:舒张早期峰值速度(E),舒张晚期峰值速度(A),E加速度及减速度,并计算E/A比值及心房舒张晚期充盈分数(AFF)。结果:二组间左心室舒张期充盈明显不同,尤其是替代治疗组E/A比值高,AFF低,替代治疗组舒张早期充盈量大于对照组。结论:本研究表明长期雌激素替代治疗可以影响左心室舒张功能。  相似文献   
63.
将胚鼠中脑腹侧组织制成细胞悬液移植于帕金森病(PD)模型鼠侧脑室,动态观察受体鼠在移植前后的行为变化。移植后16周应用诱发荧光及免疫细胞化学等方法,对移植物在受体鼠脑内的存活及生长情况进行了研究。结果,受体鼠旋转行为明显改善,侧脑室内可见黄绿色荧光细胞及酪氨酸羟化酶(TH)免疫反应阳性细胞,有的发出突起伸向室管膜及迁于尾核区.提示:移植的胚鼠黑质细胞生长良好,似作为触液神经元发挥其作用。  相似文献   
64.
Background: Protection of the right ventricular (RV) myocardium during ischaemia in cardiac surgery is difficult, especially in patients with severe right coronary artery (RCA) disease. Retrograde coronary sinus cardioplegia is thought to distribute uniformly, but doubts still remain as to its adequacy in RV preservation. This study evaluated distribution of antegrade vs. exclusively retrograde coronary sinus cold blood cardioplegia by assessing myocardial cooling and compared the effects on RV function. Methods: Fifty-eight patients scheduled for elective coronary artery surgery - 29 patients with significant RCA disease and another 29 with no significant RCA stenosis (controls) - were randomised to receive either antegrade or retrograde cold blood cardioplegia through either aortic root or conventional self-inflating coronary sinus catheter (RCA-ante, RCA-retro, C-ante and C-retro groups). RV function was assessed by fast-response thermodilution. Myocardial temperatures were measured in the anterior and posterior wall of the right and left ventricle. Results: Cooling of the posterior wall of the RV was effective only in the control patients given antegrade cardioplegia (14.7°C), whereas in the other groups the lowest myocardial temperatures there remained above 20°C (RO.001). In patients with obstructed RCA both antegrade and retrograde cold cardioplegia led to uneven cooling of the myocardium. After cardiopulmonary bypass the RV ejection fraction (RVEF), RV stroke work index (RVSWI) and cardiac index (CI) were significantly reduced in the RCA-retro group, and RVSWI and CI in the C-retro group, too. Regression analysis showed an inverse relationship between the temperatures of the posterior walls of the ventricles and changes in the RVEF and CI. Conclusions: Retrograde and antegrade cardioplegia alone were not effective in reducing the temperature of the posterior wall of the RV in the patients with obstructed RCA, in whom with retrograde cardioplegia RV haemodynamics were impaired for 1 hour following bypass. Neither retrograde nor antegrade cardioplegia alone can be relied on to protect the posterior wall of the RV in the patients with obstructed RCA.  相似文献   
65.
Background: For patients with incurable malignant gastric outlet obstruction and cholestasis, laparoscopic gastrojejunostomy combined with endoscopic biliary stent placement seems to offer a minimally invasive palliation. Methods: We retrospectively analyzed the data of 16 patients submitted to laparoscopic gastrojejunostomy. Laparoscopic gastroenterostomy was performed as an antecolic, side-to-side gastrojejunostomy with enteroenterostomy. In 12 patients cholestasis was relieved preoperatively by stent placement via endoscopy (n= 6, 37.5%), percutaneous access (n= 5, 31%) or bilioenteric anastomosis (n= 1, 6.25%). One patient needed a percutaneous Yamakawa prosthesis postoperatively. Results: Mean operative time was 126 min. There were no intraoperative complications. In one patient conversion to open surgery became necessary because of extensive adhesions. The only postoperative complication was bleeding from a trocar site requiring reintervention; there was no mortality. Median postoperative hospital stay was 7 days. Delayed gastric emptying was observed in 3 (18.7%) patients. Median survival was 87 days after the operation. All patients died from their primary disease but could maintain oral intake during the remaining survival time. Conclusions: We conclude that laparoscopic gastrojejunostomy and endoscopic or percutaneous biliary stenting provide a good functional result while impairing the quality of life only to a minimal extent. Received: 7 May 1996/Accepted: 12 December 1996  相似文献   
66.
大型颅咽管瘤的显微手术治疗   总被引:1,自引:0,他引:1  
目的:结合颅底手术入路提高鞍上、三脑室、脚间池大型颅咽管瘤的手术全切除率,提高疗效。方法:采用不同颅底手术入路显微手术切除37例鞍上、三脑室、脚间池大型颅咽管瘤。结果:肿瘤全切除35例,次全切除2例。术中解剖保留垂体柄31例,所有患者术后伴有不同程度一过性尿崩、动眼神经麻痹10例。全部病例平均随访3年,复发1例。结论:对位于鞍上、三脑室和脚间池的大型颅咽管瘤应根据肿瘤的不同生长方向采用相应的手术入路,充分暴露鞍区各脑池、视神经、前循环及其穿通支和三脑室底部等结构,对脑组织和脑神经牵拉小,术后并发症少且易控制,可取得较好的手术治疗效果。  相似文献   
67.
Objective The objective of this study was to evaluate whether the rigid application of a sterile protocol for shunt placement was applicable on a routine basis and allowed the reduction of shunt infections (SI) in children. Materials and methods Since 2001, a rigid sterile protocol for shunt placement in children using neither antibiotic-impregnated catheters nor laminar airflow was prospectively applied at Erasme Hospital, Brussels, Belgium. For assessing the protocol efficacy before continuation, we preliminarily analyzed the results of the first 100 operated children (43 females, 57 males, 49 aged <12 months; 115 consecutive shunt placement/revision procedures). All procedures were performed by the same senior surgeon, one assistant, one circulating nurse, one anesthesiologist. The sterile protocol was rigidly imposed to these four staff members: uniformed surgical technique; limited implant and skin edge manipulation; minimized human circulation in the room; scheduling surgery as first morning operation; avoiding postoperative cerebrospinal fluid (CSF) leak; double gloving; procedures of less than 30-min duration; systemic antibiotics prophylaxis. We analyzed separately: (1) children carrying an increased risk of SI (n = 38) due to preoperative external ventricular drainage, CSF leak, meningitis, glucocorticoids, chemotherapy; (2) children aged <12 months; (3) procedures for shunt revision. Results Errors in protocol application were recorded in 71/115 procedures. They were mainly done by non-surgical staff, decreased with time and were medically justified in some young children. Surprisingly, no SI occurred (follow-up, 4 to 70 months). One child developed an appendicitis with peritonitis (Streptococcus faecalis) after 6 months. No SI was found. After peritonitis was cured, shunt reinsertion was uneventful. Conclusion These preliminary results suggest that a uniform and drastic sterile surgical technique for shunt placement: (1) can be rigidly applied on a routine basis; (2) can lower the early SI rate below 1%; (3) might have a stronger impact to reduce SI than using antibiotic-impregnated catheters and optimizing the operative environment such as using laminar airflow and reducing the non-surgical staff. This last issue will be evaluated further in the present ongoing protocol.  相似文献   
68.
侧脑室引流术治疗脑室出血医院感染分析   总被引:10,自引:1,他引:9  
目的 分析治疗脑室出血侧脑室引流术后感染发生率,探讨预防感染的方法及措施。方法 根据留管时间将患者分为甲、乙两组,按单侧引流及双侧引流分为A、B组,术后观察插管部位的感染发生情况,同时定期做血培养监测。结果 甲、乙组之间,经统计学处理P<0.01,差异有高度显著性,A、B两组比较,P>0.05,差异无显著性。结论 留管1~2周时间是安全的,超过2周,感染率上升,双侧引流术后感染率高于单侧引流者,此外,患者的全身状况及免疫力也与感染率明显相关。  相似文献   
69.
中重型β地中海贫血基因类型分析   总被引:1,自引:0,他引:1  
目的 了解中间型和重型β地中海贫血基因突变类型及其相关血液,生化变化。方法 应用反向点杂交法检测16种β地贫点突变基因,常规进行血细胞分析及其他地贫筛查试验。结果 27例中重型β地贫患者中10例为纯合子,17例为双重杂合子,10例纯合子中5例CD41-42纯合子,占50%,3例TATAnt-28纯合子,占30%;CD17纯合子和IVS-nt654纯合子各1例,各占10%,17例双重杂合子中5例为IVS-nt654/CD41-42占29.4%,3例为CD17/CD41-42,占17.6%;3例为TATAnt-28/CD41-42,占17.6%;2例为βE/IVS-nt654,占11.6%;CD17/TATAnt-28,IVS-nt654/CD17,IVS-nt654/CD1-1,1CD71-72/IVS-nt654各1例,各占5.9%。27例患者血红蛋白均低于90.0g/L。平均为58.8g/L;平均MCV为65.0fl。脆性均少于60%。结论 中重型β地中海贫血基因突变类型多样,组合类型不同,临床表现轻重不一,多呈中重度贫血,血液,生化均有明显改变,多需输血维持生命,故应做好产前诊断,预防其出生。  相似文献   
70.
纤维支气管镜对右中叶肺不张的诊治价值(附50例报告)   总被引:1,自引:0,他引:1  
目的:探讨应用纤维支气管镜检查术在右中叶肺不张诊断和治疗中的价值。方法:对50例右中叶肺不张患者应用纤维支气管镜进行诊断和治疗。结果:50例右中叶肺不张中非特异性炎症29例、肺癌12例、结核3例、异物1例、未确定诊断5例,总确诊率90%(45/50);50例中33例经纤维支气管镜直视下局部治疗后复张,有效率66%(33/50),术后未见严重并发症。结论:纤维支气管镜对右中叶肺不张有一定的临床诊断和治疗价值。  相似文献   
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