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991.
992.
Alteration of benzodiazepine receptors in mouse cerebellum following methylazoxymethanol treatment during development 总被引:1,自引:0,他引:1
E Bacon N Matsokis P Roujansky J de Barry G Gombos 《Brain research. Developmental brain research》1989,47(2):293-297
The specific binding of [3H]flunitrazepam was studied to biochemically specify the morphological alterations induced in mouse cerebellum by a single injection of an antimitotic agent, methylazoxymethanol (MAM) performed at the beginning of the postnatal life. The MAM injection causes a general reduction of the benzodiazepine receptors in the adult mice which is particularly severe in mice having been injected the 1st day of postnatal life (so-called MAM0 mice) as compared to animals injected the 5th day (MAM5 mice): in MAM0 mice the benzodiazepine receptor is reduced to half of the control value. The affinity of the benzodiazepine towards its receptor was not affected and the topographic and biochemical action of MAM in the central nervous system was ascertained. Correlations could be made between the biochemical modifications and the morphological alterations otherwise described. 相似文献
993.
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995.
DRP 153 cells, which are hypersensitive to solar UV and deficient in the formation of DNA-protein crosslinks (DPC) following irradiation, were transfected with human DNA and a secondary transformant obtained in which a normal DPC response and solar UV sensitivity reestablished. DNA from this secondary transformant was used to construct a genomic DNA library from which a recombinant phage was isolated containing the human gene capable of restoring a normal DPC response and solar UV sensitivity to DRP 153. This gene has been designatedSUVCC3 to denote solar UV cross-complementing gene number 3. 相似文献
996.
Barry L. Wenig Kerstin M. Stenson Bruce M. Wenig Diana Tracey 《Lasers in surgery and medicine》1993,13(2):242-245
Sprague-Dawley rats were exposed to Nd:YAG laser exhaust (contact and noncontact) as well as to electrocautery exhaust passed through smoke evacuation filters. Exposure periods for each group were equal and increasing in time. Histologic analysis revealed alveolar congestion and emphysematous changes in all modes. Controls exhibited similar change but to a milder degree. It appears that any plume produced by lasers or electrosurgical devices produces pathologic change in rat lungs and that effective smoke evacuation will help control these effects. © 1993 Wiley-Liss, Inc. 相似文献
997.
The role of condensed tannins in the nutritional value of Lotus pedunculatus for sheep. 2. Quantitative digestion of carbohydrates and proteins 总被引:1,自引:0,他引:1
Primary growth vegetative Lotus pedunculatus containing 46 and 106 g/kg dry matter (DM) of total condensed tannin and 3 and 14 g/kg DM of free condensed tannin, was cut and fed fresh at hourly intervals (750 g DM/d) to sheep fitted with permanent cannulas into the rumen and duodenum. Low- and high-tannin lotus contained respectively 41.3 and 31.6 g total nitrogen/kg DM and 132 and 152 g lignin/kg DM. The two forms of lotus were similar in carbohydrate composition. Nutrient intake was recorded and faecal output measured by direct collection. Digesta flow to the duodenum was estimated by measuring dilution at the duodenum of inert ruthenium phenanthroline (Ru-P) and chromium-EDTA markers continuously infused into the rumen. Effects attributable to condensed tannins were assessed by comparing the digestion of the two diets, and by comparing the digestion of each with predicted values for non-tannin-containing fresh forages fed at similar intakes. Apparent digestibility of all nutrients measured was less for high- than for low-tannin lotus (P less than 0.01). The levels of cellulose digested ruminally and post- ruminally in both forms of lotus were similar to predicted values. However, less hemicellulose and readily fermentable carbohydrate (RFC; soluble carbohydrate + pectin) was digested in the rumen in sheep given both forms of lotus than would be predicted for non-tannin-containing fresh forage diets, but this was compensated for by greater post-ruminal absorption of both nutrients. Total N gains across the rumen (duodenal N flow--total N intake) were 1.8 and 10.5 g/d for low- and high-tannin lotus v. predicted losses of 3.7 and 2.1 g/d for non-tannin-containing fresh forages given at the same total N intakes. Post-ruminal digestion of non- amonia -N (NAN; proportion NAN flowing at duodenum) was 0.71 and 0.67 for low- and high-tannin lotus respectively v. 0.76 for comparable non-tannin-containing fresh forages. Energy absorbed as amino acids from the small intestine was calculated to be 0.29 of metabolizable energy for both forms of lotus, compared with 0.17 and 0.21 for perennial ryegrass and white clover. It was concluded that the presence of condensed tannins in lotus markedly increased post-ruminal NAN absorption compared with non-tannin-containing fresh forage diets, but depressed ruminal digestion of RFC and hemicellulose. 相似文献
998.
999.
No kidney transplant center responding to a kidney preservation questionnaire would accept a kidney flushed with an intracellular electrolyte solution and cold-stored for over 40 hours. This study from one center is a comparison of 50 primary cadaver kidney grafts preserved with an intracellular electrolyte flush followed by cold storage for 40 to 61 hours to 82 primary cadaver kidney grafts preserved by the same method for 9 to 24 hours. Kidneys cold-stored for over 40 hours had a significantly increased requirement for dialysis in the 1st week following transplantation (82% versus 34%) and a significantly increased 1-month serum creatinine nadir (2.3 mg/dL versus 1.7 mg/dL). Actuarial graft survivals and serum creatinine levels at 1, 2, and 3 years after grafting were not significantly different. Cadaver donor methylprednisolone (30 to 60 mg/kg) two to nine hours prior to kidney removal significantly reduced the requirement for 1st-week hemodialysis in the kidneys cold-stored for over 40 hours (60% versus 91%). Kidneys preserved by flushing with cold intracellular electrolyte solution can be successfully transplanted after over 40 hours of simple cold storage when the warm ischemia time is very short. 相似文献
1000.