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111.
L. H. Iversen † H. Harling‡ S. Laurberg P. Wille-Jørgensen‡ On behalf of the Danish Colorectal Cancer Group 《Colorectal disease》2007,9(1):38-46
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
112.
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
113.
质疑Frank—Starling心脏定律 总被引:4,自引:4,他引:0
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
114.
目的:探讨二维及彩色多普勒超声对甲状腺良、恶性结节的诊断及鉴别诊断价值。方法:120例甲状腺结节经二维超声了解其声像图表现,然后用彩色多普勒检查,观察结节内部及周边血流分布情况,并将其分为4级。结果:120例302个甲状腺结节中,良性结节264个,恶性结节38个。二维超声显示:恶性结节以实性低回声为主,内可见砂粒样钙化,边界不清,无声晕及包膜;良性结节以等、高回声及囊性、囊实性结节为主,形态规则,边界清,多有声晕及包膜。彩色多普勒超声显示:恶性结节的血流显示率明显高于良性结节,收缩期最高血流速度及阻力指数总体上高于良性结节,且以Ⅱ、Ⅲ级血流为主。结论:二维及彩色多普勒超声诊断甲状腺良、恶性结节准确率高。具有较大的临床应用价值。 相似文献
115.
喉返神经解剖在甲状腺手术中的应用研究 总被引:4,自引:0,他引:4
目的探讨解剖喉返神经在甲状腺手术中的应用。方法回顾分析因甲状腺疾病行手术治疗的236例患者的临床资料,共施行甲状腺手术335侧次;甲组101例行甲状腺手术158侧次,术中均未解剖喉返神经,其中57例行双侧甲状腺手术。乙组135例行甲状腺手术同时解剖喉返神经177侧次,其中42例因双侧甲状腺手术而行双侧喉返神经解剖。结果喉返神经损伤均发生在切除甲状腺范围包含背侧腺体时。甲组暂时性损伤2例,永久性损伤1例,损伤率为1.9%;乙组暂时性损伤1例,无永久性损伤病例,损伤率为0.56%;两组差异有统计学意义(χ2=0.382,P<0.01)。结论甲状腺手术中解剖喉返神经能减少喉返神经的损伤,切除背侧腺体时应常规解剖喉返神经。 相似文献
116.
生长抑素受体显像近年来研究较多,depreotide已成为其研究热点之一。Depreotide在诊断与鉴别诊断临床常见的孤立性肺结节方面有其独特优势;此外,^99mTc—depreotide生长抑素受体显像在乳腺癌、甲状腺癌、淋巴瘤等肿瘤及甲状腺相关性眼病等非肿瘤性疾病也有一定应用前景。 相似文献
117.
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
118.
Motoaki Nakamura Dean F Salisbury Yoshio Hirayasu Sylvain Bouix Kilian M Pohl Takeshi Yoshida Min-Seong Koo Martha E Shenton Robert W McCarley 《Neuropsychopharmacology》2007,62(7):773-783
BACKGROUND: Overall neocortical gray matter (NCGM) volume has not been studied in first-episode schizophrenia (FESZ) at first hospitalization or longitudinally to evaluate progression, nor has it been compared with first-episode affective psychosis (FEAFF). METHODS: Expectation-maximization/atlas-based magnetic resonance imaging (MRI) tissue segmentation into gray matter, white matter (WM), or cerebrospinal fluid (CSF) at first hospitalization of 29 FESZ and 34 FEAFF, plus 36 matched healthy control subjects (HC), and, longitudinally approximately 1.5 years later, of 17 FESZ, 21 FEAFF, and 26 HC was done. Manual editing separated NCGM and its lobar parcellation, cerebral WM (CWM), lateral ventricles (LV), and sulcal CSF (SCSF). RESULTS: At first hospitalization, FESZ and FEAFF showed smaller NCGM volumes and larger SCSF and LV than HC. Longitudinally, FESZ showed NCGM volume reduction (-1.7%), localized to frontal (-2.4%) and temporal (-2.6%) regions, and enlargement of SCSF (7.2%) and LV (10.4%). Poorer outcome was associated with these LV and NCGM changes. FEAFF showed longitudinal NCGM volume increases (3.6%) associated with lithium or valproate administration but without clinical correlations and regional localization. CONCLUSIONS: Longitudinal NCGM volume reduction and CSF component enlargement in FESZ are compatible with post-onset progression. Longitudinal NCGM volume increase in FEAFF may reflect neurotrophic effects of mood stabilizers. 相似文献
119.
Laura I Sacolick Douglas L Rothman Robin A de Graaf 《Magnetic resonance in medicine》2007,57(3):548-553
Because of their excellent slice profiles and high immunity to RF inhomogeneity, adiabatic full passage (AFP) pulses are ideal for use in spatial localization. The nonlinear, position-dependent phase of a single AFP pulse generated during refocusing of transverse magnetization traditionally is eliminated by using identical pairs of AFP pulses, at the expense of increased RF power deposition and increased echo time (TE). Here it is shown that one can achieve significant phase refocusing by executing single AFP pulses along non-equivalent spatial axes. When used for volume selection in MR spectroscopic imaging (MRSI) the remaining nonlinear phase becomes inconsequential when the phase across a spectroscopic volume is small. Selection of rectangular and octagonal volumes is demonstrated with half the number of AFP pulses used in the traditional approach. It is shown that octagonal volume selection in the human brain provides excellent suppression of extracranial lipids, and thus allows multislice (1)H MRSI at 4 Tesla to be performed within the guidelines for RF power deposition. 相似文献
120.
目的 研究重度充血性心力衰竭患者血流动力学的昼夜节律改变.方法 选择2005年12月至2006年6月在南京中医药大学无锡附属医院心内科住院的重度充血性心力衰竭患者120例为心衰组,同期门诊体检的无心血管疾病者20名为对照组,采用生物阻抗法每小时1次动态监测心率(HR)和每搏输出量(SV).结果 心衰组与对照组HR、SV均存在昼夜节律,但分布规律存在差异,心衰组HR明显快于对照组(P<0.5),而SV明显低于对照组(P<0.05);对照组HR与SV呈正相关(P<0.01),而心衰组HR与SV总体上也呈正相关(P<0.01),但在凌晨100~400之间,两组HR与SV分布曲线明显不同,心衰组HR与SV分布曲线出现分离现象,HR下降而SV上升,呈负相关(P<0.01),而同时段的对照组HR与SV则仍呈正相关(P<0.01).结论 重度充血性心力衰竭患者HR和SV分布的昼夜节律受损,在凌晨100~400之间,HR与SV分布趋势存在分离现象. 相似文献