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91.
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The intracortical projections of neurons in layers II and upper III of tree shrew visual cortex were studied after terminal lesions in the supragranular layers of area 17. Examination for terminal degeneration was made using ultrastructural techniques. The majority of degenerating terminals were found in layers V and, to a lesser extent, VI, and were presynaptic to neural profiles in the following distribution: 80.5% on spines of small to medium size dendrites, 19% on dendrite shafts, and less than 1% on neuronal perikarya. Degenerating axons coursed in vertical bundles through layers III, IV, V and VI. These findings are similar to those previously described in rat visual cortex. 相似文献
94.
O6-Methylguanine methyltransferase activity is increased in rat tissues by ionising radiation 总被引:3,自引:0,他引:3
The effect of whole body ionising radiation from a linear acceleratoron rat tissue O6-methylguanine (O6-meG) methyl-transferase (MT)activity has been assessed using an assay which measures thetransfer of 3H-radioactivity from 3H-methylated substrate DNAto protein. The maximal effect occurred 2 days after a 1 kraddose, at which time activity in liver extracts was increased5-fold in two different rat strains. Activity in lung and kidneywas increased 4- and 2-fold, respectively. Similar degrees ofenhancement were found in these three tissues using an h.p.l.c.method for measuring MT activity. The increase in activity wasreflected in an increased capacity to repair O6-meG producedin liver DNA by administration of [14C]dimethylnitrosamine (DMN):this effect was dose dependent, being detectable after 30 radsand maximal after 600 rads. Incorporation of labelled breakdownproducts of the DMN into adenine in DNA increased as the doseradiation increased suggesting an inhibition of DNA synthesis.The implications of these results for the mechanism of enhancingO6-meG repair are discussed. 相似文献
95.
Histopathology of lung cancer in New Mexico, 1970-72 and 1980-81 总被引:1,自引:0,他引:1
C Butler J M Samet C G Humble E S Sweeney 《Journal of the National Cancer Institute》1987,78(1):85-90
In conjunction with a population-based case-control study of lung cancer in New Mexico, the histopathology of cases diagnosed during 1980 and 1981 and during 1970-72 was reviewed. Adequate histologic or cytologic material was obtained for 725 cases, with 308 during 1970-72 and 417 during 1980-81. The light microscopic histologic type was classified on the basis of review by 2 pathologists. No significant differences were found in the histologic-type distributions in Hispanics and non-Hispanic whites. In males, the distributions of histologic types were similar in the two time periods, but in non-Hispanic white women the proportion of adenocarcinoma declined during 1980-81 as the proportion of small cell carcinoma increased. The panel classification was compared with that recorded by the New Mexico Tumor Registry. Overall agreement was 52.1% for 1970-72 and increased to 65.2% for 1980-81. The discrepancies between the two classifications were largest for the categories of large cell undifferentiated carcinoma and "other malignancy." 相似文献
96.
D. Finnerty A. Ní Eochagáin M. Ahmed A. Poynton J. S. Butler D. J. Buggy 《Anaesthesia》2021,76(11):1499-1503
Major spinal surgery causes significant postoperative pain. We tested the efficacy and safety of bilateral erector spinae block on quality of recovery and pain after thoracolumbar decompression. We randomly allocated 60 adults to standard care or erector spinae block. Erector spinae block improved the mean (SD) quality of recovery-15 score at 24 postoperative hours, from 119 (20) to 132 (14), an increase (95%CI) of 13 (4–22), p = 0.0044. Median (IQR [range]) comprehensive complication index was 1 (0–3 [0–5]) in the control group vs. 1 (0–1 [0–4]) after block, p = 0.4. Erector spinae block reduced mean (SD) area under the curve pain during the first 24 postoperative hours: at rest, from 78 (49) to 50 (39), p = 0.018; and on sitting, from 125 (51) to 91 (50), p = 0.009. The cumulative mean (SD) oxycodone consumption to 24 h was 27 (18) mg in the control group and 19 (26) mg after block, p = 0.20. In conclusion, erector spinae block improved recovery and reduced pain for 24 h after thoracolumbar decompression surgery. 相似文献
97.
Frederick H Koh Jason MW Chua Joselyn LJ Tan Fung-Joon Foo Winson J Tan Sharmini S Sivarajah Leonard Ming Li Ho Bin-Tean Teh Min-Hoe Chew 《World journal of gastrointestinal surgery》2021,13(8):734-755
A growing body of evidence has demonstrated the prognostic significance of sarcopenia in surgical patients as an independent predictor of postoperative complications and outcomes. These included an increased risk of total complications, major complications, re-admissions, infections, severe infections, 30 d mortality, longer hospital stay and increased hospitalization expenditures. A program to enhance recovery after surgery was meant to address these complications; however, compliance to the program since its introduction has been less than ideal. Over the last decade, the concept of prehabilitation, or “pre-surgery rehabilitation”, has been discussed. The presurgical period represents a window of opportunity to boost and optimize the health of an individual, providing a compensatory “buffer” for the imminent reduction in physiological reserve post-surgery. Initial results have been promising. We review the literature to critically review the utility of prehabilitation, not just in the clinical realm, but also in the scientific realm, with a resource management point-of-view. 相似文献
98.
L. J. Butler A. V. Palmer T. Spencer R. Tabios-Broadway W. J. Wall 《Clinical genetics》1987,31(4):199-205
A female child is described with multiple anomalies including epicanthus, frontal bossing, short sternum, polydactyly, cleft of the larynx, renal cysts, and unusual dermatoglyphics. She died aged 3 months and was found to have a unique de novo deletion of chromosome No. 4 (q22-q25). This case is compared with other long arm deletions of 4q and reference made to assignment of genetic markers to chromosome No. 4. 相似文献
99.
The clinical course of pulmonary embolism. 总被引:7,自引:0,他引:7
100.