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91.
The interrater reliability and concurrent validity of two methods of scoring the ensemble-averaged impedance cardiogram were evaluated. Impedance cardiographic and electrocardiographic signals were recorded from 40 undergraduate men and women during a baseline rest period and a vocal mental arithmetic task period. Recordings were scored by four raters using a conventional method, involving ensemble averaging after careful editing of beat-to-beat waveforms, and a streamlined method, involving ensemble averaging without beat-to-beat editing. Intraclass correlations for interrater reliability exceeded .92, whereas intraclass correlations for concurrent validity exceeded .97, indicating excellent agreement between raters and scoring methods for all cardiac measures. The streamlined method was significantly faster than the conventional method. The results indicate that variations in beat-to-beat editing do not constitute a serious source of error in the ensemble-averaged impedance cardiogram and support the interrater reliability and concurrent validity of the two scoring methods.  相似文献   
92.
Summary In 50 rats, different types of end-to-side carotid artery anastomoses were compared. In one technique, a longitudinal split in the long axis of the vessel was performed to enhance the diameter of the anastomosis. This theoretical advantage was not confirmed in this series. The clamping time, anastomoses time, and tamponade time were increased significantly when compared with a simple, slightly oblique end-to-side anastomosis. This study highlighted that the most simple type of end-to-side anastomosis gave less bleeding, achieved a quicker water-tight anastomosis and decreased the risk of late problems.  相似文献   
93.
Acute hyperglycaemia inhibits antroduodenal motility. In non-diabetic subjects this inhibitory effect may result from reactive endogenous hyperinsulinaemia. Therefore, we investigated the effects of hyperinsulinaemia during both hyperglycaemia and euglycaemia on interdigestive antroduodenal motility (perfusion manometry) and duodenocaecal transit time (DCTT; lactulose breath-H2 test). Six healthy volunteers (age 20–26 years) were studied for 240 min on three separate occasions in random order during: (a) i.v. saline (control); (b) acute hyperglycaemic hyperinsulinaemia (HG) with plasma glucose at 15 mmol L?1; and (c) euglycaemic hyperinsulinaemia (HI) with plasma insulin at 80 mU L?1 and glucose at 4–5 mmol L?1. Results: DCTT was significantly (P < 0.05) prolonged during HG (158 ± 23 min) compared with control (95 ± 25 min), whereas HI had no effect (100 ± 17 min). Mean duration of complete migrating motor complex (MMC) cycles was significantly (P < 0.05) reduced during HG (63 ± 9 min) compared with control (103 ± 15 min) and HI (105 ± 16 min), which resulted from a significantly (P < 0.05) shorter duration of phase II. Antral motility was significantly (P < 0.05) reduced during both HI (20 ± 8 contractions 240 min?1) and HG (9 ± 5) compared with control (43 ± 7). It is concluded that in healthy subjects hyperglycaemia prolongs DCTT, increases duodenal MMC cycle frequency and inhibits antral motility. Hyperinsulinaemia reduces antral motor activity but has no effect on interdigestive duodenal motility or DCTT. Thus, other factors, apart from insulin, mediate the inhibitory effect of hyperglycaemia on interdigestive intestinal motility and transit.  相似文献   
94.
 Saccades elicited by suddenly appearing targets show a broad distribution of reaction times. This may depend on variations in the subject’s state of preparation before target onset. To test this hypothesis, we recorded scalp event-related potentials from eight human subjects to investigate whether differences in saccadic reaction times (SRTs) are related to differences in cortical slow potentials prior to target onset. Compared with trials with medium SRTs (180–230 ms), trials with fast SRTs (130–180 ms) were found to be preceded by a more negative slow potential and trials with slow SRTs (230–280 ms) were found to be preceded by a more positive slow potential. These results support the hypothesis that cortical activation prior to target appearance influences SRTs. Received: 21 June 1996 / Accepted: 15 January 1997  相似文献   
95.
Eight female volunteers received acute doses of amitriptyline 50 mg (AMI), dothiepin 50 mg (DOT), fluoxetine 40 mg (FLU) or placebo both with and without a ‘social’ dose of alcohol (ALC) equivalent to 0·5 g/kg body weight absolute alcohol. Performance on a variety of tests of psychomotor ability and cognitive function (critical flicker fusion, choice reaction time, tracking, Maddox Wing and simulated car steering) were performed at 1·5 and 4 hours following treatment. AMI and DOT both with and without ALC impaired performance on a range of tests at either or both 1·5 and 4 hours, although the effects of AMI and AMI + ALC were more widespread and severe than those found with either DOT or DOT + ALC. FLU and FLU + ALC showed no evidence of impairment on any test at either the 1·5 or the 4 hours assessments. The results suggest that there are differences between the experimental substances, at the doses used, in their intrinsic potential for impairing aspects of psychomotor performance and cognitive function.  相似文献   
96.
Zusammenfassung Über 52 Monate wurden 4747 allgemeinchirurgische Planeingriffe prospektiv erfasst. Postoperative Komplikationen (Wundinfektion, Pneumonie, Revision, Letalität) wurden mit einem Punktescore bewertet, der die konkrete Zahl der zu erwartenden Komplikationen auf 10 Operationen der gleichen Art wiedergibt. Der Wert einer solchen Erfassung des Komplikationsrisikos zeigte sich in Verlaufsuntersuchungen, bei denen die postoperativen Komplikationen im 4-Monatsrhythmus aufgetragen wurden: Ursachen von Komplikationen konnten erforscht und beseitigt werden.  相似文献   
97.
A prospective study was conducted to evaluate a new compact portable coagulation monitor (Ciba–Corning Biotrack 512 Monitor), which enables the clinician to perform instantaneous activated partial thromboplastin time (APTT) and prothrombin time (PT). 126 patients scheduled for heparinized and nonheparinized vascular surgery, and gynaecological surgery, were included. A drop of capillary or venous whole blood was applied in disposable cartridges to successively perform APTT and PT, and the results of the tests were compared with conventional laboratory methods, performed in two different laboratories (Lab. A and B). Comparisons between Lab. A. and Lab. B. enables determination of the bias, precision, and percent of outliers (patients whose values differed more than 20%) in conventional methods. The reference value was defined as the mean of Lab. A. and Lab. B. values. For PT, there were no statistical differences between the capillary and venous samples performed with the portable monitor, and the reference value, for the bias, the precision and the proportion of outliers. For APTT, there were no statistical differences between the capillary and venous samples performed with the portable monitor, and the reference value, for the bias and the precision. The percent of outliers, however, was significantly greater with the venous sample of the compact monitor than with the reference (48 versus 22%), and even if it did not reach the statistical significance ( P = 0.07) it was also higher with the capillary sample performed with the Ciba Monitor than with the reference (33%). In conclusion the assessment of blood coagulation using this new compact monitor could be of major interest during the intraoperative period when immediate results are mandatory, even if PT is more accurate than APTT with this new method.  相似文献   
98.
U.S. cancer mortality data derived from information recorded on death certificates are frequently relied upon as an indicator of progress against cancer. A limitation of this measure is the lack of information pertaining to the onset of disease, such as year-of-diagnosis, age-at-diagnosis, stage of disease at diagnosis and histology of lesions. However, population-based cancer registries collect these types of data and allow the calculation of an incidence-file based mortality rate. This incidence-based mortality rate allows a partitioning of mortality by variables associated with the cancer onset. Breast cancer incidence-based mortality measures are created and compared to mortality rates based on death certificates over a comparable time period. Novel mortality measures, such as mortality rates by stage-at-diagnosis, age-at-diagnosis and year-of-diagnosis, are used to illustrate the value of this approach.  相似文献   
99.
The aim of the study was to evaluate endourological techniques in the management of iatrogenic ureterovaginal fistula. Seventeen patients referred to us after gynecologic surgery were diagnosed as having iatrogenic ureterovaginal fistula. First, retrograde double-J stenting was tried. If this failed, percutaneous nephrostomy using an antegrade double-J stent was performed. If this also failed, open surgical repair was performed. The retrograde double-J stent bypassed the fistula in 2 patients (11.8%). Percutaneous nephrostomy was performed in the remaining 15. The antegrade double-J stent bypassed the fistula in another 2 of these patients (11.8%). Open surgical repair was performed in the remaining 13 patients (67.5%) (direct ureteroneocystostomy) with nipple valve in 11 patients and Boari flap with psoas hitch in 2 patients). Of all patients, 2 had ureteral stricture, one after antegrade double-J stenting and the other after open repair. It was concluded that early intervention is recommended in the treatment of iatrogenic uretrovaginal fistula, causing minimal morbidity and discomfort, and being less expensive. EDITORIAL COMMENT: This is an interesting paper that is worthy of mention because of an important concept in the management of an iatrogenic ureterovaginal fistula. The traditional management of these fistulas has been ureteroneocystostomy [1]. However, recent urologic literature suggests that modern endoscopic treatment is highly successful if the passage of an internal stent is possible [2,3]. This is a concept that must be shared with our urogynecologic colleagues. In this paper, 4 of 14 patients with an iatrogenic fistula underwent placement of an indwelling stent. Of these, two were placed cystoscopically, whereas the other two were placed percutaneously. All four ureterovaginal fistulas healed successfully. However, 1 patient developed a ureteral stricture. It is noteworthy that in the combined series of Selzman [2] and this Tulane group not only were all ureterovaginal fistulas successfully treated with a stent, but only 1 of 11 patients (9%) developed a stricture. Although the sample size is small, this paper supports the conclusion that successful endoscopic placement of a double-J stent does allow the ureterovaginal fistula to heal spontaneously. Therefore, initial endoscopic management of an iatrogenic ureterovaginal fistula is a reasonable recommendation. However, equally important is the development of a ureteral stricture causing ‘silent hydronephrosis’. After stent removal the patient may develop a distal ureteral stricture with a completely asymptomatic hydronephrosis — ‘silent hydronephrosis’. Although the patient may be clinically asymptomatic, the renal units remain in jeopardy. Therefore, routine periodic follow-up with radiologic studies is warranted after stent removal.  相似文献   
100.
老年病人上腹部手术后应用PCEA的临床效果观察   总被引:1,自引:1,他引:0  
目的 观察老年人上腹部术后病人自控硬膜外镇痛 (PCEA)的疗效及对内分泌功能的影响。方法 6 3例择期行胃癌根治术的老年患者 ,ASAⅠ -Ⅱ级 ,随机分为 3组 (每组 2 1例 ) :A组术后行硬膜外镇痛 (PCEA) ;B组术后行静脉镇痛 (PCIA) ;C组术后按需肌肉注射哌替啶镇痛 ;对比术后镇痛效果并分别于麻醉前 ,切皮后 90分钟 ,术后 6 0及 1、2、3天分别抽取外周静脉血测定血糖、胰岛素、皮质醇、肾上腺素浓度。结果 A、B组镇痛效果均满意 ,C组镇痛效果欠佳 ,综合镇痛质量A组优于B组优于C组 ;3组于切皮后 90分钟血皮质醇、血糖浓度均升高 ,但A组低于C、B两组 (P <0 .0 5 ) ,术后 6 0分钟均达高峰 (P <0 0 1) ,术后 2 4至 4 8小时虽有下降 ,但仍明显高于麻醉前水平 (P <0 0 5 ) ;血胰岛素水平 ,A、B组术后 3天无明显变化 ,C组术后第 1、2天升高显著 (P <0 .0 1及P <0 .0 5 ) ;肾上腺素A、B组术后无明显升高 ,C组术后 6 0分钟明显升高 ,于术后 3天仍未恢复至术前水平。结论 老年病人上腹部术后PCIA及PCEA均能达到优良的镇痛效果 ,PCEA能有效地抑制术后机体的应激反应 ,有利于术后病人的恢复。  相似文献   
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