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51.
Reconstruction of anorectal angle after abdominoperineal resection of rectum and anus--an animal model 总被引:1,自引:0,他引:1
Voluntary control of the bowel movements is a social necessity. Lack of control relegates one to psychological debility and the possible need for a permanent colostomy. Anorectal angle plays an important role in fecal continence. In the normal individual, this angle lies in the range of 60 to 105 degrees. Perineal colostomy, once proposed for patients who had received abdominoperineal resection (APR), has been abandoned because of frank incontinence. This study used a canine model. The anorectal angle, external sphincter, internal sphincter, and the puborectalis were all destroyed after APR. The colon was pulled through the perineal defect. Enteropexy, gracilis muscle transfer, and perineal colostomy were performed to restore the anorectal angle. Barium enema was performed preoperatively and postoperatively. The anorectal angle was reconstructed within normal ranges after abdominoperineal resection of the rectum and anus. 相似文献
52.
Intramural venous leiomyosarcomas 总被引:2,自引:0,他引:2
Five cases of intramural venous leiomyosarcomas are described. Only one was localized in the inferior vena cava, the classic site; the other four cases were situated in smaller veins, namely, the short and long saphenous veins, the external jugular vein, and a superficial vein at the back of the hand. Light and, in two cases, electron microscopy, as well as immunohistochemical examinations for factor VIII, helped to establish the diagnosis. The fate of these cases indicates that size and localization are the main determining factors of outcome, whereas the level of mitotic activity is informative only if it is high. Small tumors in superficial veins that are detected early may have an excellent prognosis, even after limited removal of the tumor. 相似文献
53.
Smoking and body mass in the natural history of physical activity: prospective evidence from the Alameda County Study, 1965-1974 总被引:1,自引:0,他引:1
The prospective effects of smoking status and body mass on change in leisure-time physical activity from 1965 to 1974 were examined in a cohort of 4,622 persons 20-94 years of age from the Alameda County Study. With adjustment for age and baseline physical activity, current smokers showed a greater nine-year decline in leisure-time physical activity than those who had never smoked. The coefficient for current smokers from a multivariate linear regression model was of a similar magnitude among women and men (coefficient = -0.27, 95% confidence interval [CI] = -0.50 to -0.05 for women; coefficient = -0.26, 95% CI = -0.54 to 0.02 for men). Larger declines in physical activity were seen with increasing number of current pack-years exposure among both women and men. Compared with women of average body mass index, women of heaviest body mass index had larger declines (coefficient = -0.70, 95% CI = -1.04 to -0.36) while women of the lightest body mass index had larger increases (or smaller declines) in physical activity (coefficient = 0.33, 95% CI = 0.00 to 0.66). Although body mass index did not initially appear to be associated with a change in physical activity among men, age-specific analyses indicated that the effect of body mass index on physical activity varied with age such that younger (20-39 years of age), thinner men increased their activity, while older (60 years of age and over), thinner men decreased their physical activity more than men of the same age with average body mass index. 相似文献
54.
55.
本文对摆动从动杆盘状凸轮机构的最大压力角和最小曲率半径问题进行了详细的讨论。根据优化原理,同时考虑许用压力角和最小曲率半径,对摆动从动杆盘状凸轮机构进行了最优化设计。在仅给出摆杆运动规律、摆杆最大摆角和相应凸轮转角的情况下,直接确定凸轮的最小基圆半径、摆杆长度和摆杆初始位置角。 相似文献
56.
Hemolytic-uremic syndrome: intrarenal arterial Doppler patterns as a useful guide to therapy 总被引:1,自引:0,他引:1
Seventeen children with acute renal failure due to the hemolytic-uremic syndrome were examined with duplex Doppler ultrasound. Serial measurements of intrarenal arterial pulsatility were obtained by means of the Pourcelot index. These were compared with daily urine volume, both during the phase of renal failure (during which most of the children were undergoing peritoneal dialysis) and during recovery of renal function. During oliguria or anuria there was either no intrarenal arterial flow (ie, absent Doppler shifts), or absent, reversed, or markedly reduced diastolic flow. Within 24-48 hours after diastolic Doppler shifts returned to normal, diuresis occurred. The Doppler examination enabled prediction of recovery and allowed dialysis treatment to be abbreviated or, in some cases, canceled. 相似文献
57.
The traditional cleansing method of the large bowel usually involves dietary restrictions, purgatives and enema. They are time consuming and uncomfortable, and may result in dehydration. Though Golytely, an oral lavage solution, has been developed since 1980 as an alternative for cleansing the colon and much literature has favored it, it has not been widely used in Taiwan. In this study, we used Golytely without enema for rapid colon cleansing in a consecutive series of 48 patients. The efficacy, change of vital signs, body weights, electrolytes, and urine specific gravity were evaluated. Patient's acceptance of this method was compared with that of 32 patients who received castor oil as cleansing method. The average amount of Golytely used in this preparation was 3.16 liters, and the average time was 8 hours and 43 minutes. About 87% of patients receiving Golytely achieved a good to excellent preparation. There were no significant changes in vital signs, body weights, electrolytes and urine specific gravity. The patient's acceptance of Golytely was better than that of castor oil. 相似文献
58.
G. Jean Kant John R. Leu Sally M. Anderson Edward H. Mougey 《Physiology & behavior》1987,40(6):775-779
Rats were placed in a stressful environment for 24 hr per day and levels of plasma hormones were measured after varying numbers of days in the environment. Rats were habituated to operant chambers placed in sound-attenuated enclosures. Food pellets were available by lever press on a FR1 schedule. After 3 days of habituation, rats in the “stressed” group were trained to pull a ceiling chain to avoid or escape shock. Following training, stress trials, consisting of a consecutive sequence of 5 sec each of a warning light, warning tone and 0.16, 0.32, 0.65, 1.3 and 2.6 mA of footshock, occurred approximately once per 5 min around-the-clock. For the first day, the sequence was terminated when the ceiling chain was pulled. On subsequent days, 90% of all shock presentations could be avoided or escaped by chain pull; the remaining 10% of trials were inescapable and the entire sequence was presented. Control rats lived in identical chambers without presentation of shock. Rats were sacrificed after 1, 2, 3, 4, 7 or 14 days in this environment and levels of plasma corticosterone, ACTH and prolactin were determined. Levels of plasma corticosterone were elevated during the first 7 days in the stressful environment, but returned to control values by day 14. Levels of plasma ACTH and prolactin were similar in stressed and control rats at all time points measured. These data suggest that stress-induced changes in glucocorticoids but not in ACTH or prolactin might mediate some of the physiological changes that occur as the result of chronic stress. 相似文献
59.
T F Elsmore J K Parkinson J R Leu J M Witkin 《Pharmacology, biochemistry, and behavior》1989,32(4):971-975
The effects of atropine sulfate (ATS) and atropine methyl nitrate (ATM) on the conditional discrimination behavior of rats were investigated in eight-hour experimental sessions. Responding of rats was reinforced on either a lighted or a darkened lever depending on whether lights over both levers had been on during the preceding sample portion of the trial. Zero-delay and four-second-delay trials were randomly interspersed. Quality of performance was analyzed using the A' sensitivity measure of signal detection theory. Both drugs reduced both sensitivity and the percentage of trials on which responding occurred (percent response) below saline treatment levels. The two drugs did not reliably differ from each other in their effects on sensitivity during the zero-delay condition, but reliable differences between the two drugs emerged during the four-second-delay condition at doses above 0.8 mg/kg. Percent response recovered more rapidly for animals treated with ATS than responding occurred (percent response) below saline treatment levels. The two drugs did not reliably differ from each other in their effects on sensitivity during the zero-delay condition, but reliable differences between the two drugs emerged during the four-second-delay condition at doses above 0.8 mg/kg.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
60.