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101.
W. D. Boeckx V. V. Vijay Haribhakti L. Bosmans J. A. Gruwez 《European journal of plastic surgery》1992,15(3):127-132
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
102.
Robert D. Hienz Troy J. Zarcone Danielle A. Pyle Joseph V. Brady 《Psychopharmacology》1997,134(1):38-45
The effects of cocaine and quinpirole were studied in baboons to determine whether quinpirole, a relatively selective D2/D3 dopamine agonist, produced effects similar to those of cocaine on perceptual and motor processes. To measure perceptual and
motor function, three baboons were trained to discriminate differences between a standard vowel and four other synthetic vowels;
response accuracy as well as response latencies, or ”reaction times”, were measured following drug administrations. Cocaine
reduced reaction times in two baboons, and did not affect reaction times in a third; on the other hand, quinpirole lengthened
reaction times in a dose-dependent manner in all baboons. Cocaine and quinpirole also differed in the time course to produce
the maximal reaction time effect following drug administration. Cocaine and quinpirole did not differ consistently in their
perceptual effects, as indicated by similar changes in d′, a signal-detection index of discriminability. These distinct profiles of effects for cocaine and quinpirole suggest differing
neurochemical actions for these two drugs.
Received: 10 August 1996 /Final version: 16 May 1997 相似文献
103.
Is the effect of acute hyperglycaemia on interdigestive antroduodenal motility and small-bowel transit mediated by insulin? 总被引:2,自引:0,他引:2
H. A. J. GIELKENS M. VERKIJK M. FRÖLICH C. B. H. W. LAMERS & A. A. M. MASCLEE 《European journal of clinical investigation》1997,27(8):703-710
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
104.
S. Everling P. Krappmann A. Spantekow H. Flohr 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1997,115(3):479-484
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
105.
Ian Hindmarch 《Human psychopharmacology》1987,2(3):177-183
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
106.
CHM. SAMAMA R. QUEZADA B. RIOU E. MOURGEON M. AROCK A. ANKRI P. VIARS 《Acta anaesthesiologica Scandinavica》1994,38(3):232-237
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
107.
108.
Kenneth C. Chu Barry A. Miller Eric J. Feuer Benjamin F. Hankey 《Journal of clinical epidemiology》1994,47(12):1451-1461
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
109.
110.
腰椎间盘突出症患者手术前后血浆内皮素及降钙素基因相关肽的变化 总被引:4,自引:0,他引:4
目的 探讨血浆内皮素 (ET)及降钙素基因相关肽 (CGRP)在腰椎间盘突出症(PLID)患者手术前后的变化及其意义。方法 采用放射免疫法检测 40例正常人及 40例患者手术前后的血浆CGRP及ET值。结果 40例PLID患者术前血浆ET值明显高于正常对照组 ,术后ET值明显低于术前 (P <0 .0 1) ,但患者术后血浆ET值与正常对照组差异无显著性 (P >0 .0 5 )。40例PLID患者术前血浆CGRP值与正常对照组比较差异无显著性 (P >0 .0 5 ) ,40例PLID患者术后疼痛明显改善 ,且其血浆CGRP值明显高于术前及正常对照组 (P <0 .0 1)。正常对照组ET与CGRP无明显相关 ,病组术前ET与CGRP呈正相关 ,而术后两者无明显相关。结论 ET与CGRP共同参与了PLID的发病过程 ,为探讨PLID保守治疗方法提供了依据。 相似文献