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71.
目的:分析钛-瓷修复体失败的原因。方法:对38例瓷裂的钛-瓷修复体进行分析:①肉眼观察烤瓷崩瓷部铸件的表面颜色并用便携式厚度测试仪测量其厚度,与未发生瓷裂的正常镰铬合金烤瓷比较;②观察烤瓷崩瓷的部位;③X-ray检测铸件内部气孔。结果:本组崩瓷的钛-瓷修复体,其断层或有气泡,或金属表面氧化层明显增厚(P〈0.05)。而且,所有发生崩瓷的部位均在受力点或因技工本身操作不当引起。结论:钛-瓷修复体失败的原因与加工过程中工艺、瓷的受力点以及与钛元素化学性能有关。  相似文献   
72.
BACKGROUND: Abnormalities in calcium and vitamin D metabolism have been reported after bariatric surgery. The purpose of this study was to evaluate vitamin D nutritional status among morbidly obese patients before gastric bypass surgery. METHODS: We prospectively studied 279 morbidly obese patients seeking gastric bypass surgery for vitamin D nutritional status as assessed by serum 25-hydroxyvitamin D level. In addition, serum samples were analyzed for calcium, alkaline phosphatase (AP), intact parathyroid hormone (PTH), and 1,25-dihydroxyvitamin D. RESULTS: Mean patient age was 43 +/- 9 years; 87% of the study patients were women, and 72% were white. Serum calcium and AP levels were normal in 88% and 89% of the patients, respectively. Vitamin D depletion, defined as serum 25-hydroxyvitamin D level 相似文献   
73.
BACKGROUND: Preoperative dietary counseling (PDC) before bariatric surgery is mandated by a growing number of insurance payers. Their claim is that PDC improves outcomes and postoperative compliance. We compared outcomes of GBP patients undergoing a mandatory 13 weeks of PDC (n = 72) to a contemporaneous group of patients with no such requirement (no-PDC; n = 252) who underwent operation between January 2000 and December 2002. METHODS: The PDC and no-PDC groups were characterized by similar male:female ratios (1:4 vs 1:4.6), mean age (42 years), mean body weight (324 lb vs 309 lb), and mean body mass index (BMI) (52 kg/m2 vs 50 kg/m2). The PDC group had a higher incidence of obstructive sleep apnea compared with the no-PDC group (41% vs 28%; P < .04) but otherwise the two groups had similar incidences of obesity-related comorbidities. The presurgery dropout rate was 50% higher in the PDC group than in the no-PDC group (28% vs 19%; P < .05). RESULTS: At 1 year follow-up, the no-PDC patients had a statistically greater percentage excess weight loss (67% vs 60%; P < .0001), lower BMI (32 vs 35; P < .015), and lower body weight (197 vs 218; P < .01). Resolution of major comorbidities, complication rates, 30-day postoperative mortality, and postoperative compliance with follow-up were similar in the two groups. CONCLUSIONS: The data demonstrate that insurance-mandated PDC is an obstacle to patient access for surgical treatment of severe obesity and has no impact on weight loss outcome or postsurgical compliance. PDC should be abandoned by the insurance industry.  相似文献   
74.
INTRODUCTION H pylori infection is an established risk factor for development of gastric cancer[1,2]. According to the model of carcinogenesis of the intestinal type adenocarcinoma proposed by Correa, the multi-step development starts from the condition o…  相似文献   
75.
目的比较2%强化戊二醛(下称戊二醛)气雾熏蒸法与浸泡消毒法消毒吸痰管的效果.方法消毒按5周期(1个周期12 d)进行,每周期将200根使用过的吸痰管经初步处理,即5% 84消毒液浸泡30 min后清水冲洗干净晾干.将每周期200根吸氮管随机均分为实验组和对照组,实验组采用戊二醛原液气雾熏蒸法消毒4 h,对照组采用戊二醛原液浸泡消毒30 min,12 d为1个周期.两组分别于第1、6、12天对消毒后的吸痰管及消毒过程中的戊二醛采样行细菌菌落数计数,并观察有无细菌生长.结果两组每周期第1、6天吸痰管和消毒液标本均未检测出细菌,且无致病微生物生长;每周期第12天对照组吸痰管和消毒液标本均检测出细菌,实验组未检测出细菌.结论气雾熏蒸法消毒灭菌效果可靠,具有节约开支、使用方便、有利于吸痰管的保存与放置等优点.  相似文献   
76.
不同性别的大学生心理健康调查研究   总被引:2,自引:0,他引:2  
目的:探讨不同性别的大学生心理状况的影响。方法:以260名大学生为研究对象,采用SCL-90对不同性别的大学生进行了评定。结果:女生在抑郁、焦虑和恐怖方面高于男生,两者均存在显著性差异(P〈0.01)。结论:大学生中女性学生存在一定的心理缺陷,应针对性地开展专业教育,帮助大学生建立稳定、乐观和积极进取的健康心理。  相似文献   
77.
Background: For management of bowel obstruction due to colorectal cancer, endoscopic trans‐anal decompression technique has been first reported by Lelcuk et al. in 1986 using balloon dilatation technique. Since then, various types of trans‐anal decompression tubes have been clinically used for patients suffering from left side obstructing colorectal cancer as an emergent decompressing device. At present, two types of trans‐anal ileus tube (trans‐anal decompression tube) have been available for clinical use, but they have two main problems that are late colon perforations caused by the tip of the tube and tube obstruction by stool. Methods: Analysis on three late colon perforations experienced with the use of conventional devices drew possible improvements to make a trans‐anal ileus tube less harmful. To overcome the pitfalls inherent to conventional tubes, the author has developed an improved trans‐anal ileus tube with a balloon installed at the very end of the tube (‘balloon‐tipped type’) made of silicone, measuring 1200 or 1700 mm in total length and 22 Fr in outer diameter. It has been used for 12 cases with obstructing colorectal cancer etc. and its outcomes were compared with those obtained by the use of conventional trans‐anal ileus tube. Results: No late perforations have been encountered, but tube obstruction did occur in one of 12 cases. Conclusion: The new trans‐anal ileus tube with a balloon installed at the tip of ileus tube is considered to be safer and especially effective in preventing late colon perforation and tube obstruction.  相似文献   
78.
BACKGROUND: A primary tubular sodium handling abnormality has been implicated in the edema formation of nephrotic syndrome. Dopamine synthesized by renal proximal tubules behaves as an endogenous natriuretic hormone by activating D(1)-like receptors as a paracrine/autocrine substance. METHODS: We examined the time courses of the urinary excretion of sodium, protein and dopamine in puromycin aminonucleoside (PAN)-treated and control rats. The rats were sacrificed during greatest sodium retention (day 7) as well as during negative sodium balance (day 14) for the evaluation of renal aromatic l-amino acid decarboxylase (AADC) activity, the enzyme responsible for the synthesis of renal dopamine. Also, the influence of volume expansion (VE) and the effects of the D(1)-like agonist fenoldopam (10 microg/kg bw/min) on natriuresis and on proximal tubular Na(+),K(+)-ATPase activity were examined on day 7. RESULTS: The daily urinary excretion of dopamine was decreased in PAN-treated rats, from day 5 and beyond. This was accompanied by a marked decrease in the renal AADC activity, on days 7 and 14. During VE, the fenoldopam-induced decrease in proximal tubular Na(+),K(+)-ATPase activity was more pronounced in PAN-treated rats than in controls. However, the urinary sodium excretion during fenoldopam infusion was markedly increased in control rats but was not altered in PAN-treated animals. CONCLUSION: PAN nephrosis is associated with a blunted renal dopaminergic system activity which may contribute to enhance the proximal tubular Na(+),K(+)-ATPase activity. However, the lack of renal dopamine appears not to be related with the overall renal sodium retention in a state of proteinuria.  相似文献   
79.
80.
黄海 《右江医学》2002,30(6):469-470
目的 :探讨胃癌穿孔的临床特点 ,指导临床诊治和提高疗效。方法 :对本院 2 4例胃癌穿孔病人采用不同手术方式治疗。其中 8例行单纯修补术 ,2例在穿孔修补术后 3周早期施行二期根治性手术 ,3例行穿孔修补加胃空肠吻合术 ,7例行姑息性胃大部切除术 ,4例行胃癌根治术。结果 :本组死亡 4例 ,其余病例中位生存期分别为 7,13 .2 ,2 5 .1个月。结论 :采取积极的治疗措施 ,可望延长患者的生存时间和提高生存质量  相似文献   
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