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941.
942.
943.
Seventeen patients who had undergone extensive small bowel resection were studied for calcium absorption (FACa) and plasma vitamin D metabolites. FACa was measured by a double radio-tracer technique and expressed as percentage of total oral dose. FACa was decreased compared with controls (34%, range: 3-46 v 65%, range: 57-73, P less than 0.01). A positive correlation (r = 0.49, P = 0.05) was found between FACa and the remaining length of small bowel (SBL). As wide variations in both SBL and duration after surgery were observed among the seventeen investigated patients, we were led to individualize less heterogeneous subgroups of patients. Better correlations were found when the patients were divided into two subgroups according to whether the time interval between the resection and the investigation was shorter (r = 0.75, n = 11, P less than 0.02) or longer (r = 0.89, n = 6, P = 0.05) than 2 years. In thirteen patients who had a SBL shorter than 100 cm, a positive correlation was observed between FACa and the time interval after surgery (months): r = 0.65, P less than 0.05. Plasma 1,25 (OH)2D was markedly reduced in the whole group (31 pmol l-1, range: 8-108) compared with controls (103 pmol-1, range: 59-134, P less than 0.01). The present study shows that in extensively small bowel resected patients, calcium absorption is reduced, the alteration being dependent both on the length of the remnant small bowel and on the time after surgery.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
944.
945.
A selected ion monitoring assay for thiodiglycollic acid in urine is described. Urine samples are analysed by combined gas chromatography-mass spectrometry as their dibutyl esters using pimelic acid as an internal standard. Rapid analysis was achieved by the simplification of sample preparation. The assay has proved to be reliable, with a detection limit of less than 0.5 mumol/l. The excretion of large amounts of thiodiglycollic acid in premature babies urine has been confirmed, with the greatest excretion occurring from those neonates born with a gestational age of 30 wk or less.  相似文献   
946.
The late results--up to six years--after axillo-femoral bypass reconstruction are reported for 85 patients with leg ischaemia who were regarded as poor-risk patients for aortic bypass surgery, or who had aortic graft infection. Velour-Dacron grafts and expanded polytetrafluoroethylene (PTFE, Gore-Tex)--grafts have been used. The cumulative patency rate (life table) six years after graft implantation was 64% (PTFE-grafts) and 58% (Velour-Dacron grafts). The corresponding cumulative limb salvage rate six years after graft implantation was 88% when PTFE grafts were used and 77% when Velour-Dacron grafts were used. Our results demonstrate that axillo-femoral reconstruction is a useful procedure with a good patency rate 6 years after implantation. This procedure should be considered when dealing with poor risk patients with severe leg ischaemia.  相似文献   
947.
948.
Synovectomy of the knee in patients with hemophilia presenting in countries with demographic characteristics that make central referral difficult is the subject of this article. Ten patients, six surgeons, and two countries contributed to this study, which demonstrated that approximately 40% of these patients had no further hemarthroses into the affected joint and the remainder had reduced frequency and severity of bleeding. Continuous passive motion has an important place in postoperative management, and manipulation with the patient under anesthesia is of doubtful value. The possible relationship between diminished range of movement and a successful outcome in terms of abolition of hemorrhage is explored. One patient underwent synovectomy of the knee without complication; the other nine suffered significant complications.  相似文献   
949.
We tested whether hypoglycemia, like hypoxia, would preferentially destroy GABAergic nerve cells in the neocortex. To this end, rat neocortex explants dissected from 6-day-old rat pups and cultured up to a developmental stage approximately comparable to that of the newborn human neocortex, were exposed to hypoglycemia for different periods. Quantitative light microscopic and immunocytochemical evaluation of the cultures demonstrated that hypoglycemia does not preferentially destroy GABAergic but rather non-GABAergic neurons, a finding quite opposite to what was found after hypoxia. Recent biochemical data from other laboratories which seem to support this difference in neuronal vulnerability are discussed. It is concluded that perinatal hypoglycemia may not form such a serious threat with respect to the genesis of epilepsy as does hypoxia.  相似文献   
950.
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