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101.
The effect of acute and sequential volaemic changes on the gastroduodenal flow of saline was assessed in 23 anaesthetized dogs following two different experimental protocols. Hypervolaemia, by i. v. infusion of saline, induced a gradual decrease on gastroduodenal flow which amounted to 76% below control values (P < 0.001) when volaemic expansion attained 5% of body weight. This effect was volume dependent (17% increase on gastroduodenal flow per volume of infused saline equivalent to 0.5% of body weight, P < 0.001), lasted for at least 90 minutes after infusion was completed and was also obtained by expanding previously bled animals. Hypovolaemia due to bleeding was followed by an increase on gastroduodenal flow of about 88% above control values (P < 0.05) when haemorrhage was equal to 3% of body weight. This effect was also volume dependent (23 % increase on gastroduodenal flow per volume of blood shed equivalent to a 0.5% of body weight, P < 0.01) and was reversed after blood volume was restored. These modifications in the resistance of the gastroduodenal segment to the flow of liquid due to acute volaemic changes suggest that the extracellular fluid volume modulates the contractile activity of the gastroduodenal portion of the gut possibly to set a gastroduodenal handling of liquid adequate to cope with volaemic imbalances.  相似文献   
102.
重视介入性肺减容术的研究   总被引:5,自引:2,他引:3  
介入性肺减容术是在外科切除肺减容术和内镜下非外科切除肺减容术的基础上发展起来的。它是一项X线导引下的经导管治疗技术,在靶肺叶经支气管行博来霉素(或无水乙醇)碘油乳剂栓塞的同时并对其近端支气管用骨水泥封堵,可获得稳定的肺纤维化和肺减容,即所谓的功能性肺叶切除。虽然此项介入治疗技术目前仍处于动物实验阶段,但已经显露出其临床应用潜力和广阔的前景。  相似文献   
103.
本实验建立小鼠足容积测量方法学并提供小鼠足容积的生理数值,为进一步研究实验性皮肤癌发生的免疫机制打下基础.根据毛细管放大原理,使用自制的小鼠足容积测量仪测量351只昆明种小鼠左右足容积,发现左右足容积几乎相等.另对150只小鼠左右足进行369次重复测量,发现合格测量超过97%.不同体重小鼠足生长曲线研究表明,随着体重的增加,小鼠足容积渐趋于一定值,表明生长停止.并且体重25g以上小鼠活体离体足容积差接近一定值,这提示大龄小鼠足血管张力和容积基本恒定.  相似文献   
104.
对25例非胰岛素依赖型糖尿病(NIDDM)患者及24例正常人进行全套肺功能检查,并作对比分析,结果表明:NIDDM组比正常对照组V25/HT减低。差异有高度显著性(P<0.01);DLCO减低差异有显著性(P<0.05),并认为NIDDM患者小气道功能、弥散功能减低与糖代谢紊乱,致机体抵抗力降低、免疫功能下降,并与肺胞毛细血管基底膜增厚有关。检查NIDDM患者小气道功能和肺泡弥散功能,具有一定临床意义。  相似文献   
105.
Rhenium-186 hydroxyethylidene diphosphonate (186Re-HEDP) has been used for the palliative treatment of metastatic bone pain. A phase 1 dose escalation study was performed using 186Re-HEDP Twenty-four patients with hormone-resistant prostate cancer entered the study. Each patient had at least four bone metastases and adequate haematological function. Groups of at least three consecutive patients were treated with doses starting at 1295 MBq and increasing to 3515 MBq (escalated in increments of 555 MBq). Thrombocytopenia proved to be the dose-limiting toxicity, while leucopenia played a minor role. Early death occurred in one patient (10 days after administration) without clear relationship to the 186Re-HEDP therapy. Transient neurological dysfunction was seen in two cases. Two patients who received 3515 MBq 186Re-HEDP showed grade 3 toxicity (thrombocytes 25–50 × 109/1), defined as unacceptable toxicity. After treatment alkaline phosphatase levels showed a transient decrease in all patients (mean: 26% ± 10% IUA; range: 11%–44%). Prostate-specific antigen values showed a decline in eight patients, preceded by a temporary increase in three patients. From this study we conclude that the maximally tolerated dose of 186Re-HEDP is 2960 MBq. A placebo-controlled comparative study on the efficacy of 186Re-HEDP has been initiated.  相似文献   
106.
OBJECTIVE: We reviewed recent literature to assess the impact of hospital caseload, surgeon's caseload and education on long-term outcome following colorectal cancer surgery. METHOD: We searched the MEDLINE and Cochrane Library databases for relevant literature starting from 1992. We selected hospital caseload, surgeon's caseload and surgeon's education, type of hospital, and surgeon's experience as variables of interest. Measures of outcome were recurrence-free survival and overall survival, and for rectal cancer frequency of permanent stoma. We reviewed the 34 studies according to tumour location: colonic cancer, rectal cancer, or colorectal cancer. We described the studies individually and performed a meta-analysis whenever it was considered appropriate. RESULTS: For colonic cancer, overall survival improved with increasing hospital caseload, odds ratio (OR) 1.22 [95% confidence interval (CI) 1.16-1.28], and surgeon's education. For rectal cancer, overall survival improved with increasing hospital caseload, OR 1.38 (95% CI 1.19-1.60), and, possibly by surgeon' education and experience. Cancer-free survival was strongly influenced by surgeon's education. The colostomy rate was less in high caseload hospitals, OR 0.76 (95% CI 0.68-0.85). For colorectal cancer, overall survival improved with surgeon's education. CONCLUSION: The data have provided evidence that long-term survival following colorectal cancer surgery in general improved significantly with increasing hospital caseload and surgeon's education.  相似文献   
107.
OBJECTIVE: An association between caseload and outcome has been reported for complex surgical procedures. We systematically reviewed recent literature to determine whether caseload and surgical speciality are associated with short-term outcome following colorectal cancer surgery. METHOD: We searched the MEDLINE and Cochrane Library databases for relevant publications starting in 1992. We selected hospital caseload and type, and surgeon's caseload, education and experience as variables of interest. Measures of outcome were postoperative morbidity, in-hospital and 30-day mortality, and for rectal cancer anastomotic leak. We stratified the 35 reviewed studies by tumor location: colonic cancer, rectal cancer, or colorectal cancer and described the studies individually. A meta-analysis was performed only when it was considered appropriate. RESULTS: For colonic cancer, postoperative morbidity was associated with surgeon's caseload and education. Postoperative mortality was strongly associated with hospital caseload (OR 0.64, 95% CI 0.55-0.73), and surgeon's caseload (OR 0.50, 95% CI 0.39-0.64). It was also influenced by surgeon's education and experience. For rectal cancer, we found no evidence of an association between the selected variables and short-term outcome, including frequency of anastomotic leak. For colorectal cancer, there was evidence for an association between postoperative morbidity and hospital caseload. CONCLUSION: Our review offers evidence for a positive association between high hospital caseload, surgeon's caseload, sub-speciality and experience and improved short-term outcome in colonic cancer surgery. We failed to find evidence of a relationship for rectal cancer surgery, possibly owing to methodological artifacts. No study reported an inverse relation.  相似文献   
108.
质疑Frank—Starling心脏定律   总被引:4,自引:4,他引:0  
何川  何培芳 《西部医学》2009,21(10):1639-1646
心脏收缩释放的能量(作功)是心肌纤维长度(心室舒张末期容积,EDV)的函数,即Frank—Star一1ing(FS)心脏作功定律,被誉为心脏生理学中的“经典”理论。对此,笔者从各种不同角度进行了探讨:首先分析了Frank伸展离体心肌和Starling及其同事使用心肺制备做的实验与动物生理实际的差异,以及人们在实验中观测到的增加心肌前负荷引起收缩力增强的现象(FS现象),认为:①在正常生理条件下的动物体内,来自心脏以外的、如同心肺制备中那样人工控制心室充盈压力升高、引起EDV增加的那种血液的重力动力是不存在的。②另一方面,人为地增加前负荷,那是改变了心肌收缩时的外环境条件。③由此而激发出的FS现象,是心脏适应其外环境条件变化所作出的反应。④此种心肌收缩力增强的反应,需通过心肌细胞内部与收缩过程发生有关的心肌兴奋一收缩和化学一力学偶联等一系列生化机制(不恒定因素)方能得以实现。⑤根据他们实验中观测到的FS现象,在逻辑上不能得出前负荷这一心肌收缩时的外环境条件变化调控其作功的推论。换言之,所有的在实验中被激发出来的FS现象,都不足以成为支持FS心脏定律的证据。然后,引用国内外公认的计算心脏每搏射血作功(w)的生物物理学公式“w=P×(EDV—ESV)”,证明了w和EDV之间没有函数关系。根据心脏作功的医用物理学和生物数学的基本原理,笔者认为Frank—Starling心脏定律表达的不是心脏作功的规律。  相似文献   
109.
目的:评价低剂量容积数据高分辨率CT重组图像在肺部疾病中的应用价值。方法:对50例肺部疾病患者进行低剂量多层螺旋CT(MSCT)、高分辨率CT(HRCT)扫描及容积数据HRCT重组,比较所得到的低剂量容积数据HRCT重组图像和HRCT扫描图像质量并进行分级评分。结果:50例肺部疾病患者的低剂量容积数据HRCT重组图像和HRCT扫描图像质量相同,两者差异无统计学意义(P=0.188)。所见征象评分P值均>0.05,肺实变、网状影、蜂窝影、肺气肿、肺大泡得分趋向一致。低剂量MSCT扫描降低80%辐射量,缩短扫描时间。结论:低剂量容积数据HRCT重组图像评价肺部疾病的价值与HRCT扫描图像相同。低剂量容积数据HRCT重组大大降低辐射量,明显缩短检查时间,复检患者尤其适用,可以替代HRCT扫描。  相似文献   
110.
Appetite and obesity: a gastroenterologist''s perspective   总被引:2,自引:0,他引:2  
This review focuses on the gastrointestinal tract's control of appetite and interventions directed to the gut that are effective in the treatment of obesity. It examines the evidence linking gut hormones to the control of both appetite and upper gastrointestinal motility, the evidence that stomach function is altered and contributes to satiation in obesity and outlines the principles of therapy for obesity which are directed at the gastrointestinal tract. These therapies impair fat absorption or alter stomach functions through pharmacological, device, endoscopic, or surgical approaches. Gastroenterologists need to understand the role of factors controlling appetite in order to effectively manage the increasing number of obese patients and the ways the gut function may be altered as a result of the treatments and their complications.  相似文献   
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