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排序方式: 共有1629条查询结果,搜索用时 31 毫秒
1.
Guerard W. Byrne Johannes M. Schirmer David N. Fass Sumeet S. Teotia Walter K. Kremers Hui Xu Bashoo Naziruddin Henry D. Tazelaar John S. Logan Christopher G. A. McGregor 《American journal of transplantation》2005,5(5):1011-1020
Microvascular thrombosis is a prominent feature in cardiac delayed xenograft rejection (DXR). We investigated the impact of warfarin or low-molecular-weight heparin (LMWH) anti-coagulation on xenograft function using a heterotopic pig-to-primate model. Donor hearts were from CD46 transgenic pigs and baboon immunosuppression included tacrolimus, sirolimus, anti-CD20 and TPC, an alpha-galactosyl-polyethylene glycol conjugate. Three groups of animals were studied. Group 1 (n = 9) was treated with warfarin, Group 2 (n = 13) with LMWH and Group 3, received no anti-coagulant drugs. The median duration of xenograft function was 20 days (range 3-62 days), 18 days (range 5-109 days) and 15 days (range 4-53 days) in Groups 1 to 3 respectively. Anti-coagulation achieved the targeted international normalized prothrombin ratio (INR) and anti-factor Xa levels consistent with effective in vivo therapy yet, no significant impact on median xenograft function was observed. At rejection, a similar histology of thrombosis and ischemia was apparent in each group and the levels of fibrin deposition and platelet thrombi in rejected tissue was the same. Anti-coagulation with warfarin or LMWH did not have a significant impact on the onset of DXR and microvascular thrombosis. However, a role for specific anti-coagulant strategies to achieve long-term xenograft function cannot be excluded. 相似文献
2.
Northern Ireland: Political violence and self- reported physical symptoms in a community sample 总被引:1,自引:0,他引:1
In order to investigate the possible relationship between physical health and political violence in Northern Ireland a random sample of residents of four electoral areas (two with relatively high violence and two with relatively low violence) was interviewed at home. Each person was asked to rate their health in terms of common physical symptoms, to indicate their use of family doctor and hospital services, and to rate the level of political violence in their neighbourhood. Analysis of covariance (with a measure of psychological well-being, a measure of trait neuroticism plus age and socioeconomic status as covariates) revealed that women reported more physical symptoms than did men, people in the ‘high’ violence areas reported more symptoms than did those in the ‘low’ violence areas, while those who rated their own neighbourhood most highly in terms of perceived violence also reported the greatest number of physical symptoms. However, a series of χ2 tests revealed no association between political violence or perceived political violence and uptake of services. 相似文献
3.
Lage Burström Ronnie Lundström 《International archives of occupational and environmental health》1988,61(3):213-216
Summary A possible basis for risk assessment of human exposure to vibration when using hand-held tools may be to determine the amount of mechanical energy that is absorbed by the hand-arm system. The aim of this investigation was to study the absorption of mechanical energy in the human hand-arm system during exposure to sinusoidal vibration within the frequency range of 20 to 1500 Hz. A handle, specially designed for this type of experiments, was used during the measurements. The influence of various experimental conditions, such as three different hand-arm postures, grip force (25–75 N) and vibration levels (27–53 mm/srms), were studied on eight subjects. The outcome clearly shows that the energy absorption properties of the human hand-arm system are more or less dependent on all of the experimental conditions studied, but mainly to the frequency of the vibration stimuli. Furthermore, the results indicate a non-linear relationship between the energy absorbed and all other variables studies. 相似文献
4.
D H Abramson C A Servodidio B McCormick D Fass E Zang 《The British journal of ophthalmology》1990,74(6):359-362
Serial ultrasonic measurements of 82 uveal melanomas treated with brachytherapy plaques (cobalt-60 and iodine-125) and followed up for up to 141 months revealed that no two patients had identical patterns of change. The mean absolute change in tumour height after treatment was 1.8 mm at six months, 5.6 mm at 48 months for large tumours, and 0.9 and 1.9 mm for medium sized tumours. Eighty of the 82 patients fell into one of three patterns of response: 57 patients had a decrease in height after treatment (type D), 13 patients had the same height after treatment (type S), and 10 patients had a progressive increase in height (type I). Life table comparison showed no correlation between survival and location of tumour, sex of patient, size of tumour when treated, or laterality. There was a slight correlation between age and survival. Patients older than 60 died more frequently from metastatic melanoma than those under 60 (p = 0.06). Life table analysis showed a significant correlation between tumour regression type and survival. At 48 months the best cumulative probability of survival was in patients with type D (88% alive) compared with those of type I (34% alive, p = 0.0004). 相似文献
5.
The indications for elective treatment of the neck in cancer of the major salivary glands. 总被引:8,自引:0,他引:8
J G Armstrong L B Harrison H T Thaler H Friedlander-Klar D E Fass M J Zelefsky J P Shah E W Strong R H Spiro 《Cancer》1992,69(3):615-619
To define the indications for elective neck treatment, the cases of 474 previously untreated patients were reviewed who had locally confined major salivary gland cancers treated between 1939 and 1982. Clinically positive nodes were present in 14% (67 of 474). Overall, clinically occult, pathologically positive nodes occurred in 12% (47 of 407). By univariate analysis, several factors appeared to predict the risk of occult metastases; however, multivariate analysis revealed that only size and grade were significant risk factors. Tumors 4 cm or more in size had a 20% (32 of 164) risk of occult metastases compared with a 4% (nine of 220) risk for smaller tumors (P less than 0.00001). High-grade tumors (regardless of histologic type) had a 49% (29 of 59) risk of occult metastases compared with a 7% (15 of 221) risk for intermediate-grade or low-grade tumors (P less than 0.00001). In view of the low frequency of occult metastases in the entire group, routine elective treatment of the neck is not recommended. High-grade tumors and larger tumors have a high rate of occult neck metastases, and treatment should be considered in this group. 相似文献
6.
Previous research has shown that exogenous gangliosides improve recovery of learned alternation after unilateral lesions of the entorhinal cortex. Since this recovery is thought to depend upon axonal sprouting, it has been hypothesized that ganglioside-induced improvement may be due to enhanced sprouting. The present study examined the effects of ganglioside treatments on learned alternation after bilateral entorhinal lesions. Whereas control rats exhibited a severe impairment postoperatively, ganglioside-treated (50 mg/kg total brain gangliosides; i.m.) rats committed significantly fewer errors and perseverative errors, and reached criterion sooner. The two groups exhibited comparable rates of daily improvement in performance. Since bilateral entorhinal lesions preclude the sprouting which is important for recovery of alternation, the ganglioside-induced improvement observed in the present study appears to be independent of sprouting. 相似文献
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9.
Ronnie Lichtman 《Journal of Midwifery & Women's Health》1996,41(1):47-49
The Governing Board of the ACNM Division of Accreditation (DOA) has been charged by the ACNM Board of Directors to consider requiring an entry-level degree for nurse-midwifery practice. This decision has far-reaching implications and must be considered with utmost care. The decision will not be based on the issue of clinical competence but rather, the political statement to be made through the imposition of a degree requirement. The author urges the DOA's Governing Board to consider the implications of its action on a variety of audiences, including potential students, potential consumers, other health professionals, current and future employers, our international colleagues, health insurers and managed care organizations, and policymakers and lawmakers. 相似文献
10.
Scott Walker Ron Masson Ronnie Telford David White 《Health services management research》2007,20(4):253-260
The paper reports the results of a study on benchmarking activities undertaken by the procurement organization within the National Health Service (NHS) in Scotland, namely National Procurement (previously Scottish Healthcare Supplies Contracts Branch). NHS performance is of course politically important, and benchmarking is increasingly seen as a means to improve performance, so the study was carried out to determine if the current benchmarking approaches could be enhanced. A review of the benchmarking activities used by the private sector, local government and NHS organizations was carried out to establish a framework of the motivations, benefits, problems and costs associated with benchmarking. This framework was used to carry out the research through case studies and a questionnaire survey of NHS procurement organizations both in Scotland and other parts of the UK. Nine of the 16 Scottish Health Boards surveyed reported carrying out benchmarking during the last three years. The findings of the research were that there were similarities in approaches between local government and NHS Scotland Health, but differences between NHS Scotland and other UK NHS procurement organizations. Benefits were seen as significant and it was recommended that National Procurement should pursue the formation of a benchmarking group with members drawn from NHS Scotland and external benchmarking bodies to establish measures to be used in benchmarking across the whole of NHS Scotland. 相似文献