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71.
72.
Virginia F J Newcombe Guy B Williams Joanne G Outtrim Doris Chatfield M Gulia Abate Thomas Geeraerts Anne Manktelow Hywel Room Leela Mariappen Peter J Hutchinson Jonathan P Coles David K Menon 《Journal of cerebral blood flow and metabolism》2013,33(6):855-862
Traumatic brain injury (TBI) is often exacerbated by events that lead to secondary brain injury, and represent potentially modifiable causes of mortality and morbidity. Diffusion tensor imaging was used to characterize tissue at-risk in a group of 35 patients scanned at a median of 50 hours after injury. Injury progression was assessed in a subset of 16 patients with two scans. All contusions within the first few days of injury showed a core of restricted diffusion, surrounded by an area of raised apparent diffusion coefficient (ADC). In addition to these two well-defined regions, a thinner rim of reduced ADC was observed surrounding the region of increased ADC in 91% of patients scanned within the first 3 days after injury. In patients who underwent serial imaging, the rim of ADC hypointensity was subsumed into the high ADC region as the contusion enlarged. Overall contusion enlargement tended to be more frequent with early lesions, but its extent was unrelated to the time of initial imaging, initial contusion size, or the presence of hemostatic abnormalities. This rim of hypointensity may characterize a region of microvascular failure resulting in cytotoxic edema, and may represent a ‘traumatic penumbra'' which may be rescued by effective therapy. 相似文献
73.
Doris Burtscher 《Stomatologie》2011,108(3):a3-a4
In den letzten Jahren l?sst sich eine steigende Nachfrage nach keramischem Zahnersatz verzeichnen. Sei es aus Biokompatibilit?tsgründen,
aus ganzheitsmedizinischen oder ?sthetischen überlegungen – Keramik wird nicht nur als Restaurationsmaterial immer pr?senter,
sondern auch in der zahn?rztlichen Implantologie. 相似文献
74.
Doris M. Bixby-Hammett 《The Physician and sportsmedicine》2013,41(8):82-86
In brief: Head injuries are the most frequent and most severe of all injuries in equestrian sports. It has been estimated that head injuries make up approximately 20% of all horse-related injuries. They can be prevented or their severity can be reduced by wearing properly fitted and secured headgear. A good helmet must be secured from loss, protect the head from the impact or compression of a fall, and resist penetration. The author recommends that the medical community continue to work to make the most protective riding helmet acceptable to the equestrian community. 相似文献
75.
Schaeffer D 《Zeitschrift für Gerontologie und Geriatrie》2004,37(4):307-315
In the following article, two of the increasingly important public health scientific disciplines of care for the elderly are compared under systematic aspects - gerontopsychiatry and nursing science - with the aim of determining the similarities and differences of both disciplines. There follows a discussion of social challenges facing the area of caring for the elderly suffering from psychiatric illnesses and the responsibilities which both disciplines have to cope with in the future. The clearing of the numerous existent geronto-psychiatric deficits in health care in Germany seems to be the main challenge. 相似文献
76.
An endogenous digitalis-factor derived from the adrenal gland: studies of adrenocortical tumor cells
The present studies demonstrate that the murine adrenocortical tumor cell line Y-1 releases a digoxin-like immunoreactive material into both serum-supplemented nutrient medium and minimal Krebs-Ringer bicarbonate medium. Release of pregnenolone into minimal medium from these cells was consistently inhibited by addition of the cholesterol side-chain cleavage inhibitor aminoglutethimide. However, release of digoxin-like immunoreactivity (DLI) was not similarly affected. To exclude the possibility that DLI could be accounted for by cross-reaction with another known adrenal steroid, aminoglutethimide inhibition was accompanied by inhibition of 17 alpha-hydroxylase with SU-10603 and inhibition of 3 beta-hydroxysteroid dehydrogenase with cyanoketone. Once again, pregnenolone release was effectively inhibited, but no similar pattern of inhibition of DLI release was observed. Increasing the time of the incubation periods from 1 to 2 h did not change the pattern of secretion of pregnenolone or DLI. HPLC analysis of DLI released over prolonged culture periods into serum-supplemented nutrient medium showed high levels of DLI in a single major and several adjacent peaks. Analysis of the ability of extracts of Y-1-conditioned medium to compete with tritiated ouabain for binding to erythrocytes indicates that conditioned medium contained highly enriched levels of ouabain-like activity. On HPLC analysis, the distribution of this activity showed partial correlation with the distribution of DLI. These observations indicate that Y-1 cells produce and release significant quantities of a material with cardiac glycoside-like properties reflected in the cross-reactivity with antidigoxin antibodies and the ability to compete with ouabain for binding to erythrocytes. In substantiation of previous findings in chopped adrenal cultures, the cardiac glycoside-like activity does not appear to result from cholesterol side-chain cleavage or pregnenolone production, since inhibition of side-chain cleavage as well as subsequent 17 alpha-hydroxylation and 3 beta-dehydrogenation did not result in consistent inhibition of DLI release. 相似文献
77.
Stem cell carcinoma of the colon and rectum 总被引:2,自引:2,他引:2
Dr. Doris H. B. Palvio M.D. Flemming B. Sørensen M.D. Mogens Kløve-Mogensen M.D. 《Diseases of the colon and rectum》1985,28(6):440-445
Two cases of highly malignant tumors, one originating in the sigmoid colon and the other in the rectum, are presented. Both tumors showed light microscopic, electron microscopic, and immunohistochemical evidence of multidirectional differentiation. The tumors were composed mainly of undifferentiated cells, but focally merging into areas with adenocarcinomatous and squamous differentiation. Ultrastructurally and histochemically, a predominant endocrine differentiation was present in the undifferentiated areas of the tumors. These two cases lend further support to the recent concept of a pluripotential stem cell in the mucosa of the gastrointestinal tract capable of differentiation in several directions. 相似文献
78.
A retrospective review of 67 patients with acute cervical spine fracture and/or dislocation was conducted at two suburban community hospital emergency departments. The mean age was 39, and two-thirds of the patients were male. Motor vehicle accidents and falls accounted for more than 80% of all injuries. On emergency department evaluation, it was found that there was no history of loss of consciousness in 42 patients (63%), no associated cranio-facial injuries in 31 patients (46%), and a normal sensorimotor examination in 59 patients (88%). Thirty-four patients (50%) were evaluated for cervical range of motion, which was found to be normal in one-third of the cases. The absence of mental status changes, cranio-facial injuries, range of motion abnormalities, and focal neurological findings is, therefore, not uncommon in patients who have sustained cervical spine injury. 相似文献
79.
Betzana Zambrano Fernando Noriega Gustavo H. Dayan Doris Maribel Rivera Jos Luis Arredondo Humberto Reynales Kleber Luz Carmen Deseda Matthew I. Bonaparte Edith Langevin Yukun Wu Margarita Corts Stephen Savarino Carlos A. DiazGranados 《The American journal of tropical medicine and hygiene》2021,104(1):136
80.
Kang H. Zheng Sotirios Tsimikas Tania Pawade Jeffrey Kroon William S.A. Jenkins Mhairi K. Doris Audrey C. White Nyanza K.L.M. Timmers Jesper Hjortnaes Maximillian A. Rogers Elena Aikawa Benoit J. Arsenault Joseph L. Witztum David E. Newby Marlys L. Koschinsky Zahi A. Fayad Erik S.G. Stroes S. Matthijs Boekholdt Marc R. Dweck 《Journal of the American College of Cardiology》2019,73(17):2150-2162