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951.
To study the effects of suture material, calibre and tension on the end-to-end oesophageal anastomosis, the cervical oesophagus of the rat was resected for 2.5 mm, 7.5 mm and 12.5 mm respectively in three groups of 60 rats each. End-to-end anastomosis was performed with either 6/0 silk, 6/0 polypropylene or 9/0 polypropylene sutures. There was no postoperative leakage. Mortality was mainly due to hair bolus obstruction at the site of anastomosis. There was no difference in mortality and anastomotic stenosis between groups with different resection lengths. Within each group, however, mortality and anastomotic stenosis were significantly higher in the subgroup of rats with 6/0 silk suture than that in the subgroup with 6/0 polypropylene sutures, which also had significantly higher mortality and anastomotic stenosis than the subgroup with 9/0 polypropylene sutures. Histological examination of the stenosed anastomosis showed disruption of muscle layers and submucosal thickening. It is concluded that the use of fine calibre sutures of biologically inert material would be preferred for the end-to-end anastomosis of the oesophagus. 相似文献
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We studied functioning cells of GH-producing pituitary adenoma quantitatively by the immunohistochemical method using anti GH antibody and compared the result with clinical hormonal data by discussing a clinical significance of the immunohistochemical study of pituitary adenoma. Fifteen acromegalics with pituitary adenoma, who underwent surgical operation followed by immunohistochemical study, were subjected. Volume of the adenoma was calculated on the basis of thin coronal cut CT scanning. The specimen was stained after PAP method. The quantitative analysis was done by investigating the ratio of anti GH antibody positive area in 30 fields (SAR). Using the value obtained, stained volume (SV) was calculated by multiplying total volume by SAR. The SV was regarded as total volume of GH positive cells. These values were compared to the preoperative serum GH levels. The results were as follows: (1) Immunohistochemically, the adenomas were classified into two types, the sporadic type and the diffuse type, by incidence of GH positive cells. SAR ranged from 0.2% to 52.4%, and means of the types were 3.0% and 24.8%, respectively. (2) All the eosinophilic adenomas demonstrated to be the diffuse type and the mean SAR was 23.7%. On the contrary, 75% of chromophobe adenomas were the sporadic type and the mean SAR was 4.9%. (3) There was no significant correlation between the serum GH level and the volume of the adenoma. There was an especially high correlation between the serum GH level and SV with a correlation constant of 0.971. (4) In fibrous adenomas the serum GH level was extremely low for their total volume. 相似文献
956.
957.
Low molecular weight heparin compared with unfractionated heparin in prevention of postoperative thrombosis 总被引:2,自引:0,他引:2
M Samama P Bernard J P Bonnardot S Combe-Tamzali Y Lanson E Tissot 《The British journal of surgery》1988,75(2):128-131
Three consecutive randomized open studies have been carried out to determine the optimal dosage of low molecular weight heparin (LMWH) in the prevention of postoperative thrombosis in general surgery (892 patients). All patients undergoing abdominal, gynaecological, thoracic or urological surgery were over 40 years old and presented at least one of the following risk factors for thrombosis: previous thromboembolism, obesity, varicose veins, malignancy (30 per cent), pre-operative hospitalization over 5 days, oestrogen therapy, chronic cardiac disease or bronchitis. Isotopic venous thrombosis and bleeding complications were assessed after subcutaneous administration of a LMWH fragment (LMWH, Enoxaparine) or unfractionated heparin (UH). The three studies compared 3 X 5000 units UH daily with 1 X 60 mg, 1 X 40 mg, 1 X 20 mg LMWH daily. Thromboembolic events rates were not significantly different from group to group (UH: 3.8 per cent, 2.7 per cent, 7.6 per cent respectively compared with LMWH: 2.9 per cent, 2.8 per cent, 3.8 per cent). Bleeding episodes including wound haematoma formation, perioperative blood losses and systemic haemorrhage were not significantly different in patients receiving LMWH or UH. Significant decreases in haematocrit and haemoglobin were only observed in patients receiving 60 mg Enoxaparine (as compared to UH). An analysis using the 'intention to treat' approach gave results consistent with those of an analysis of good compliers. An overview of isotopic thromboses in the three studies gave no evidence of differences amongst the effects of the three doses of LMWH (P = 0.20), and pooling the results of the three studies using the Mantel-Haenszel procedure gave no evidence of a global difference between Enoxaparine and UH (P = 0.54). These results suggest that an optimal dosage of 20 mg/day of Enoxaparine is safe and effective in the prevention of postoperative thrombosis in this population. 相似文献
958.
A kinetic study of leucine metabolism in severely burned patients. Comparison between a conventional and branched-chain amino acid-enriched nutritional therapy. 下载免费PDF全文
A cross-over design study was used to examine the metabolic consequences of enteral feeding for 48 to 96 hours with either a branched-chain amino acid (BCAA)-enriched (44% BCAA) or a conventional egg protein formulation in 12 severely burned adult patients. A stable isotope labeled leucine (L-1-13C-leucine) tracer approach was used to measure leucine flux and oxidation and to estimate rates of whole body protein synthesis and breakdown. Additionally, 15N2-urea and 6,6-2H-glucose were administered to assess the status of urea and glucose kinetics with these two nutritional treatments. Average patient age was 54 years, and average burn surface area was 36%. Studies were conducted at an average of 25 days postburn. Leucine flux and oxidation were significantly (p less than 0.01, by paired t-test) elevated with BCAA feeding as compared to the egg protein formulation. However, there were no significant differences in the rates of leucine incorporation into, or release from, proteins (p greater than 0.05) between the two dietary periods. Mean rates of body protein synthesis and breakdown for each diet were about twice the rates reported for healthy young adults. Apparent nitrogen balance measurements were not statistically different (p greater than 0.1) between the two diet periods. Furthermore, urea and glucose kinetics failed to show significant differences between the two diet periods. It appears from these results that the major consequences of increased intake of leucine from the BCAA formula is an enhanced rate of leucine oxidation. In conclusion, (1) the availability of BCAAs is not rate-limiting for enhanced protein synthesis in burn patients, and (2) the use of enriched BCAA formulas in burn therapy does not appear to offer advantages over a routinely used enteral egg protein formula, at least based on the present determinations. 相似文献
959.
The neural control of smooth muscle cells in the corpus spongiosum, helicine artery and bulbus glandis of the dog was investigated in relation to the mechanism involved in erection, using isometric tension recording and micro-electrode methods. In the corpus spongiosum, field stimulation evoked twitch-like contractions followed by relaxations. These relaxations were enhanced and prolonged by neostigmine and partly suppressed by atropine. Guanethidine abolished the twitch-like contractions and increased muscle tone. The relaxations observed after pre-treatment with guanethidine were abolished by tetrodotoxin (TTX), thereby indicating that these muscles are innervated by adrenergic excitatory, cholinergic and non-adrenergic non-cholinergic inhibitory nerves. In the helicine artery and bulbus glandis, field stimulation evoked contractions and these contractions were abolished by guanethidine or TTX, indicating that these muscles are innervated by adrenergic excitatory nerve fibres. After pre-treatment with guanethidine and atropine, muscle relaxation appeared in response to field stimulation in the helicine artery but not in the bulbus glandis, indicating that the helicine artery in the corpus spongiosum is also innervated by non-adrenergic non-cholinergic inhibitory nerves in addition to the excitatory adrenergic nerves. In the smooth muscle cells of the corpus spongiosum, slow potential changes were correlated with spontaneous contractions and field stimulation evoked excitatory or inhibitory junction potentials. The neural mechanism involved in erection is discussed in relation to the topical difference in the autonomic innervation patterns in the corpus spongiosum, helicine artery and bulbus glandis. 相似文献
960.
Radiotherapy was applied to 14 esophageal carcinomas with respiratory tract fistulas using various treatment regimens. Closure of the fistulas was observed in four cases after irradiation at a daily dose of 1.5 Gy. The period of closure was transient in two cases but long-term in the other two. One long-term closure case underwent low-dose rate telecobalt therapy (LDRT)(1 Gy per hour, 7 Gy per day; a total dose of 28 Gy) as a boost. His cancer has been well controlled and he is still alive without recurrence at 74 months after fistula formation. 相似文献