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991.
992.
993.
Serial coronal or sagittal sections were stained for myelin and examined in 6 inbred, 4 hybrid, and 2 outbred mouse strains. Absent corpus callosum was seen only in BALB/cJ as reported by Wimer, but a wide range of the size of corpus callosum was also noted. The action of a major gene was not evident in backcross or F2 generations; polygenic and perhaps epistatic inheritance was indicated. In A/J, and to a lesser extent A/HeJ and BALB/cJ, the columns of fornix frequently collided with the anterior commissure and either passed around it to make a normal termination or deflected dorsally to make an abnormal termination in lateral septum. In some BALB/cJ brains the anterior commissure instead was displaced and passed behind or through the columns of fornix. Backcross and F2 data suggested inheritance was polygenic and that genetic variation affected the spatio-temporal coordination of ontogeny of the two tracts. Finally, unusual longitudinal bundles were detected in the septal region of BALB/cJ. Results of crosses were consistent with the hypothesis that a single, incompletely dominant gene was acting, but further study of both the anatomy and heredity of the defect was deemed necessary.  相似文献   
994.
995.
A comparison was made of the McLaughlin nail plate and the Richards sliding screw-plate techniques for fixation of trochanteric hip fractures. The series included 96 patients in each group. The fractures were followed radiographically for 3 months.

Technical failures were encountered in 31 per cent of the McLaughlin fractures and in 8 per cent of the Richards fractures; reoperation was performed in 9 per cent in McLaughlin vs none in the Richards fractures. The main failure was varus displacement in both groups, always combined with lateral cutting of the screw in the Richards fractures, and often combined with failure of the nail-plate junction in McLaughlin fractures. Our study has shown that the sliding screw-plate is superior to the nail plate in both stable and unstable fractures.  相似文献   
996.
OBJECTIVES: Severe sternum necrosis requiring extended resection necessitates plastic reconstruction of the resulting defect and stabilization of the chest. We analyzed the outcome of patients undergoing bilateral pectoralis major flap repair on functional and cosmetic results, chest stabilization and pulmonary function. METHODS: Twelve patients undergoing cardiac surgery between 1997 and 2001 suffered from a deep mediastinal wound infection and sternum necrosis. After a mean of two attempts of extensive wound debridement, all 12 patients underwent complete sternal resection with plastic reconstruction by bilateral pectoralis major flaps. Risk factors were obesity (n=10) and diabetes (n=11). Six months postoperatively patients underwent physical examination, pulmonary function testing and functional CT scan. RESULTS: Three patients died in hospital (two septic multiorgan failure, one heart failure) and nine were discharged with complete wound closure. One patient suffered a lethal stroke during follow-up. At 6-month follow-up no recurrent sternum infection had occurred. Chest stability was satisfactory without impairment of pulmonary function (VC 77.5+/-12.1% at follow-up vs 77.8+/-12.5% preoperatively). Mobility and force of arms and shoulder were adequate; at CT scan the maximum distance change between the former sternoclavicular joint in inspiration versus expiration was minimal. Quality of life questionnaires showed no significant limitations except a disturbed sleep and mild restriction of executing hobbies and social activities. CONCLUSIONS: Bilateral pectoralis major flap repair is a safe technique to cure severe mediastinitis necessitating complete sternal resection. Wounds close without extensive reconstructive surgery. Cosmetic results as well as stabilization of the chest were good. Patients reported an almost uncompromised quality of life without respiratory impairment.  相似文献   
997.
Recent studies demonstrate the feasibility of microdialysis to monitor metabolism in ischemic livers. Whether these parameters correlate with markers of liver cell integrity in an experimental model using pig livers and different preservation solutions was an aim of this study. Pig livers were flushed with either 4 degrees C Histidine-Typtophan-Ketoglutarate solution (HTK) (Custodiol), University of Wisconsin solution (ViaSpan), and hydroxyethyl starch, or 12 degrees C saline solution. After 24-h storage, the livers were rinsed with saline to measure liver enzymes and lactate from the effluate. Utilizing microdialysis, intraparenchymal lactate, pyruvate, glucose, and glycerol was monitored. Tissue biopsies were taken for histological examinations. Cold preservation resulted in a decrease of metabolic activity measured by intrahepatic glucose, lactate, and pyruvate levels, as well as lactate in the effluate, independently of the solution used. Of particular interest, glycerol levels partially reflected the extent of hepatocellular damage and liver enzyme release. Glycerol levels partially discriminated preservation of different quality and were in accordance to histological findings and liver enzyme release. Lactate, pyruvate, and glucose levels were not appropriate as markers during cold storage. Whether or not glycerol monitoring could represent an additional and rational complementation to the current practice of macroscopic, microscopic and donor evaluation has to be clarified by further studies.  相似文献   
998.
Radiotherapy in Addition to Radical Surgery in Rectal Cancer   总被引:2,自引:0,他引:2  
In order to lower unacceptably high local failure rates after surgery reported as curative for rectal cancer, perioperative radiotherapy has been extensively investigated. The collected information from a number of controlled trials indicates that the proportion of local recurrences is reduced to less than half when radiotherapy at moderately high doses is given preoperatively. This reduction in local failure rates is not seen after postoperative radiotherapy, even if higher doses have been used. Possibly, there is also a slight positive influence on survival from preoperative radiotherapy. Improved survival has been seen also in trials using postoperative radiotherapy, but then only when combined with chemotherapy. With proper dose planning, sufficiently high doses can be given preoperatively with little if any increase in postoperative mortality. Thus, although published knowledge is still rather limited, a properly planned preoperative radiotherapy seems to inflict small bowel and other complication rates, that are less than when radiotherapy of similar efficacy against the tumour is given postoperatively.  相似文献   
999.
1000.
The influence of previous exposure to glucose on the subsequent B- and A(2)-cell secretory responses to arginine was investigated in the perfused pancreas of the rat. Arginine (8 mM) was administered in two brief (9 min) pulses separated by a period of 66 min. In pancreata from 18-h-fasted animals the two pulses of arginine elicited biphasic glucagon secretory responses, while stimulation of insulin release was barely detectable. When 27.7 mM glucose was administered for 30 min during the intervening period up to 20 min before the second pulse of arginine, the glucagon response to arginine was diminished by 55% while the insulin release was markedly increased in comparison with the first pulse. 8.3 mM glucose, when administered before the second pulse of arginine, exerted effects that were smaller but otherwise similar to those of 27.7 mM glucose.The inclusion of 3.9 mM glucose during the stimulation periods with arginine decreased the glucagon and greatly increased the insulin secretory response. Under these conditions, previous exposure to 27.7 mM glucose inhibited the glucagon and enhanced the insulin response to the second stimulatory pulse of arginine to the same relative degree as when arginine was administered alone.Diazoxide (2 mM), when administered together with 27.7 mM glucose, almost completely inhibited insulin release induced by the presence of glucose, yet did not influence the modulation exerted by glucose on the subsequent insulin and glucagon secretory response to arginine. Conversely, these effects of the glucose pulse could not be reproduced by 1 mug/ml of porcine insulin. Previous exposure to glyceraldehyde (10 mM) mimicked the glucose effects.Also, in pancreata from fed rats, previous exposure to 27.7 mM glucose markedly inhibited subsequent arginine-induced glucagon secretion while the concomittant insulin response was enhanced.IT IS CONCLUDED THAT: (a) both A(2)- and B-cell responsiveness is modulated by a previous exposure to glucose which produces opposite effects in the two cell types, (b) this action of glucose does not depend on its insulin-releasing capacity, and (c) instead, a "memory" of glucose is induced as a consequence of the metabolism of the sugar in the A(2) and B cells.  相似文献   
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