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931.
932.
P Friedmann W C Park I I Afonya J R Chabot J L Garb O T Pace R W Emery 《American journal of surgery》1978,135(4):512-518
A series of sixty-five patients with adenocarcinoma of the rectum and rectosigmoid is reviewed. Thirty-two patients had surgery alone, fourteen patients underwent postoperative radiation therapy, and nineteen patients underwent preoperative radiation therapy. A moderate dose program of 4,000 to 4,500 r was used. The postoperative treatment group had a higher incidence of stage C lesions and a higher recurrence rate, but there were no statistically significant differences in survival. Postoperative radiation therapy in patients with stage C lesions did not prolong life and is of little benefit. The preoperative treatment group tolerated the radiation very well, and there were no major complications. Eight patients underwent anterior resections in irradiated fields. Two minor anastomotic leaks subsequently healed spontaneously. There were no pelvic recurrences in the preoperative treatment group, and the incidence of lymph node metastases was 26% as opposed to 41% in controls. We conclude that preoperative moderate dose radiation is not associated with increased risk of morbidity or mortality. It may be useful in reducing the incidence of lymph node metastases and pelvic recurrence. The effect on survival is not determined in this study. 相似文献
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938.
Although suppressor cells appear to be involved in the normal regulatory mechanism of the lymphoid system, they are also considered to have a role in the immunosuppression of certain malignancies. Suppressor activity of lymphocytes can be reproducibly measured by use of the mixed lymphocyte culture-mitogen interaction (MLC-M) in which the stimulating cell either is in the basal state or has been induced by Concanavalin A. This yields a quantitative measure of resting suppressor cell activity as well as the maximum generation of suppressor activity as induced by Con A. This test was performed, using autologous and allogenic cell combinations in a group of 13 cancer patients and 18 normal controls. Normal lymphocytes activated by Con A in 48-hour lymphocyte cultures significantly decreased the mitogenic response of lymphocytes from healthy, male donors to phytohemagglutinin (PHA), Con A, and Pokeweed mitogen (PWM) in both autologous and homologous systems. In contrast, Con A activated lymphocytes from cancer patients demonstrated diminished suppressor activity compared with controls in autologous (P less than 0.01), and allogenic (P less than 0.005) systems. There was a correlation between the degree of immunosuppression and suppressor cell activation: i.e., the patients most depressed generally had the lowest suppressor cell activation. Untreated lymphocytes from cancer patients also exerted suppressive effects on normal lymphocyte responses, suggesting an increased resting level of suppressor cells. These data suggest that in addition to having depressed cellular immune responses, cancer patients frequently have reduced capability to generate suppressor cell activity, which implies a generalized defect in this aspect of immune regulation. 相似文献
939.
One hundred and twenty-four patients with knee osteoarthritis were reviewed at three stages over a mean of 24 months (range: 9-32 months) at the time of referral by the general practitioner, by the orthopedic consultant, and before surgery. At each visit, patients were examined and the American Knee Society score and Oxford Knee Society score were obtained. The functional element of the American Knee Score deteriorated significantly from the time of referral until the time of first orthopedic consultation (P=.005) and from the time of referral to the time of surgery (P=.006). The pain element of the American Knee Society score improved from the time of referral till the time of orthopedic assessment (P=.011). The change in Oxford Knee Society score between the time the patient was put on the waiting list to the time of surgery was not statistically significant (P=.30). This article questions the emphasis on surgical waiting times instead of symptoms and physical function in determining timing of surgery. 相似文献
940.
Rollin X Wauters JB Bodin NL Larondelle Y Ooghe W Wathelet B Abboudi T 《The British journal of nutrition》2006,95(2):234-245
Eighteen groups of seventy Atlantic salmon (Salmo salar L.) fry (initial mean body weight 0.8 (sd 0.01) g) were fed on semi-purified diets containing graded levels of l-threonine (Thr) in 15 litres aquaria at a temperature of 14.5+/-1 degrees C. Doses of Thr represented 1, 31, 41, 51, 62, 72, 83 and 93 % of its ideal level for optimum protein deposition. Indispensable amino acids other than Thr were included in the same proportion (on a g/16 g N basis) as in the Atlantic salmon fry whole-body carcass. Following 36 d of feeding and a 36 h fast, fry were killed for whole-body protein and amino acid analysis. Weight gain (r2 0.98), protein accretion (r2 0.97), and Thr accretion (r2 0.97) were linear (P<0.01) functions of Thr intake. Slope of the Thr accretion regression line showed that the efficiency of Thr utilisation above maintenance was 76 %. At zero Thr intake, fry lost 5.4 mg Thr/kg body weight0.75 per d. The Thr maintenance requirement was 7.2 mg/kg body weight0.75 per d and the Thr requirement for growth was 66 mg for 1 g protein deposition. Increasing doses of Thr resulted in increased (P<0.05) concentrations of histidine and lysine, and decreased concentrations of isoleucine in whole-body protein. The maintenance need for Thr represented 13.4 % of the total need for Thr. The data suggest that efficiency of Thr utilisation above maintenance is constant at all levels of Thr intake between 1 and 93 % of the level required for optimum protein deposition. 相似文献