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991.
992.
993.
Twenty patients undergoing major upper-gastrointestinal-tract or pancreaticobiliary surgery were randomized to receive postoperative nutritional support by total parenteral nutrition (TPN) or elemental diet administered by needle-catheter jejunostomy (NCJ). Both routes of administration provided adequate nutritional support. No unexpected complications were encountered. The NCJ group compared favorably with the TPN group at the end of the seven-day trial. The NCJ group provided significant cost efficiency while maintaining adequate nutritional support.  相似文献   
994.
The biochemical and histochemical measurement of the enzyme gamma-glutamyltransferase (GGT) was undertaken in normal rat pancreas and in rat pancreas containing azaserine-induced preneoplastic nodules. A steady decrease in pancreatic GGT activity was observed in the normal animals as they aged from 5 to 34 weeks. The azaserine-induced nodules contained a lower average GGT activity than the control pancreas although a 10-fold variation was noted in the GGT activity of individual nodules. A significant increase in concentrations of both reduced glutathione and oxidized glutathione was noted in pancreatic nodules from azaserine-treated rats compared to concentrations found in both control pancreas from untreated rats and internodular pancreas from azaserine-treated rats. A pancreatic acinar cell carcinoma contained low GGT activity--similar to that found in large nodules and about 10% of the level found in control pancreas. Pancreatic GGT levels were higher in 5- and 7-week-old rats fed chow than in rats fed a purified diet, but this effect of chow was not observed at 34 weeks of age. Feeding a purified diet supplemented with a retinoid, N-2-hydroxyethylretinamide (2-HER), for a period of 2 weeks did not influence the GGT activity level in either normal pancreas or in the azaserine-induced nodules. While decreased GGT activity does not serve as a marker for all atypical acinar cell nodules, deficient activity with concomitant increased glutathione levels appears to correlate generally with increased growth potential.  相似文献   
995.
Visor wear habits, evaluative comments and vision test data were obtained from interviews of 126 Navy fighter pilots. The interviews revealed that many pilots use their helmet sun visor whenever they fly, some use it only during certain flight operations, and others never use it. Study 1 (conducted at 343 cd/m2) revealed a decrease in low contrast visual acuity attributable to helmet sun visor use in the presence of a glare source. These findings prompted a second study of the visual effects of visor transmittance. Low-contrast spot detection, acuity, and contrast sensitivity were measured at an operationally realistic daytime illumination level (6870 cd/m2) in subjects viewing through filters ranging from 6.3% to 50.1% transmission. (Standard visor transmission is 12 +/- 4%.) Results showed that filter density, and consequently the illuminance reaching the eyes, could be varied over a wide range without critically affecting these visual functions. Prevailing environmental illuminance should be considered when selecting sun visors or sunglasses. These results have implications for optimizing visual performance through visors.  相似文献   
996.
997.
This case illustrates the course of an obstructive process through spontaneous perforation resulting in decompression of dilated bowel loops. The resulting meconium peritonitis appeared as fetal ascites. Postnatal investigations and laparotomy confirmed the diagnosis of a rare form of multiple congenital atresias of the bowel.  相似文献   
998.
999.
We retrospectively reviewed the computed tomographic (CT) examinations of 15 cases of abdominal wall hernia due to abdominal trauma; 13 patients had been injured in motor vehicle accidents (11 of those were belted in). All hernias were correctly identified on CT and confirmed intraoperatively. Traumatic abdominal wall hernia proved an important indicator of associated visceral injury, especially to the bowel (n = 6) and mesentery (n = 10). Careful review of the bowel and mesentery should thus be undertaken when disruption of the abdominal wall is documented. Radiologists should be aware, however, that CT findings may correlate poorly with severity of injury in these areas. In these instances, close clinical correlation and, sometimes, rescanning may be necessary.  相似文献   
1000.
The immunopathological appearances of skin and rectum in 64 autologous and allogeneic recipients were determined before and after bone marrow transplantation. Patients who developed acute graft-versus-host disease were biopsied as soon as a clinical diagnosis was made. At the same time peripheral blood samples were collected for comparative analysis. Immunohistological and morphometric techniques were employed using a panel of monoclonal antibodies to T lymphocytes and subsets, B lymphocytes, natural killer cells, macrophages, and Langerhans cells. A reduction in the CD4/CD8 ratio after BMT was seen in skin and rectal biopsies from both autologous and allogeneic recipients with or without GVHD. The same pattern was observed in blood samples taken at the same time. Langerhans cells were reduced in the skin in all patients after BMT, probably by the conditioning regimen. Only a few cells expressing activation or natural killer cell markers were present and there were no changes observed in the macrophage population. This study has provided no evidence to implicate either CD4- or CD8-positive T lymphocytes as the initiators of the cellular damage in acute GVHD. The distribution of lymphocyte subsets in the blood was similar to that in the tissues, suggesting that the tissue changes reflect the pattern of lymphocyte repopulation after BMT and may have little bearing on the pathogenesis of GVHD.  相似文献   
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