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81.
Summary The effects of acute arterial subdural bleeding on cerebrospinal fluid (CSF) pressure and 12 other vital parameters were studied in spontaneously breathing pigs (group 1, n=9) and in mechanically ventilated pigs (group 2, n=18) to analyze quantitatively the bleeding course and the lethal mechanism.Spontaneously breathing animals all succumbed after a mean bleeding volume of 45.6±8.9ml, corresponding to about 50 per cent of the intracranial volume, and a mean bleeding duration of 11.0±2.6 min. Rapid rise in CSF pressures, marked transtentorial pressure gradients, and progressive reductions of cerebral perfusion pressure leading to a permanently iso-electric EEG, apnoea and to a terminal rise in arterial pressure (Cushing response), was the rule in these animals.The mechanically ventilated animals had smaller bleeding volumes (34.3±8.1 ml), but longer bleeding durations (13.8±5.8 min). In this group 7 animals survived. They had no pressure gradients, and only moderate changes in arterial pressure and EEG. The 11 animals that succumbed had marked transtentorial pressure gradients, but smaller increments in arterial pressure than the spontaneously breathing animals.At autopsy, subdurally located blood was found throughout the intracranial and spinal subdural compartments and along the spinal nerve roots in both groups.The results of this study suggest that survival after acute subdural haematoma is influenced by the presence of transtentorial pressure gradients and by the spinal sac acting as a space for expansion. The beneficial effect of artificial ventilation is discussed.This study has been supported by the University of Oslo, The Anders Jahre Foundation for The Advance of Research, and by the Norwegian Society for fighting Cancer. 相似文献
82.
对12只开胸狗做心导纳图、阻抗图,测量(dy/dt)_(max),(dy/dt)_(max)/T_(R-y),(dz/dt)_(max)和(dz/dt)_(max)/T_(R_z)。然后改变测量电极间距L和基础阻抗Z,发现前者可引起(dy/dt)_(max)、(dy/dt)_(max)/T_(R-y)的显著变化;后者可引起(dz/dt)_(max)、(dz/dt)_(max)/T_(R-z)非常显著的变化。由心导纳图、阻抗图所得心脏每搏量(SV)与电磁流量计所测SV的相关系数分别为0.691和0.678。提示两法测量心脏泵血功能有相同的可靠性,但前者受L影响较大,后者对Z_0的变化敏感。 相似文献
83.
A. A. SANTOS J. XAVIER-NETO A. T. SANTIAGO JR. M. A. N. SOUZA A. S. MARTINS F. ALZAMORA F. H. ROLA 《Acta physiologica (Oxford, England)》1991,143(3):261-269
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
84.
85.
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
86.
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
87.
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
88.
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
89.
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
90.
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