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排序方式: 共有1263条查询结果,搜索用时 46 毫秒
141.
Marion Rother Erik Gonzalez Ana Rita Teixeira da Costa Lea Wask Isabella Gravenstein Matteo Pardo Matthias Pietzke Rajendra Kumar Gurumurthy Jörg Angermann Robert Laudeley Silke Glage Michael Meyer Cindrilla Chumduri Stefan Kempa Klaus Dinkel Anke Unger Bert Klebl Andreas Klos Thomas F. Meyer 《Cell host & microbe》2018,23(5):661-671.e8
142.
Ana B. Rodríguez Eduardo Ortega Robert W. Lea Carmen Barriga 《Molecular and cellular biochemistry》1997,168(1-2):185-190
A functional connection between the pineal gland and the immune system in mammals and birds has been established. This study investigates the effect of melatonin upon the non-specific immunity of heterophils isolated from the ring dove. The different stages of the phagocytic process: adherence to nylon fiber, spontaneous and induced mobility, ingestion of latex beads and digestion were evaluated for heterophils incubated in the presence of 5, 25, 50, 75, or 100 \sgmaelig;M of melatonin. In addition, the chemoattractant power of the hormone for heterophils was studied. The 100 \sgmaelig;M melatonin dose possessed a significant chemoattractant ability for heterophils whilst ingestion of latex particles was enhanced at all doses studied. The superoxide anion level, as measured by the free radicals produced during the metabolic burst, is decreased after incubation with 100 \sgmaelig;M of melatonin. 相似文献
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Arnold W. W. Lea 《BMJ (Clinical research ed.)》1905,1(2307):581-584
146.
Three patients with chronic uremia and one patient with glutethimide intoxication were treated by peritoneal dialysis at the Prince Edward Island Hospital, Charlottetown. The procedure was discovered to be technically simple and was carried on in one instance for five days and in another for six days without undue difficulty. The dialysis was initiated by the authors on each occasion, but was carried on by graduate nurses under supervision. It is concluded that this procedure is practical and of value for use in relatively small non-teaching hospitals, provided one or more members of the medical staff become familiar with the indications, technical details and complications of the procedure. 相似文献
147.
Lea C. Steeves 《CMAJ》1963,88(14):732-735
The experience of one Faculty of Medicine in developing programs of continuing medical education in community hospitals is presented. After mention of the importance of regular reading of the medical literature, and the problems created by its growing volume, the necessity of supplementary programs in community hospitals is pointed out. The different patterns of community hospital meetings that evolved to meet various circumstances in the Atlantic Provinces are detailed. A “course” consisting of six weekly evening meetings, followed by morning case presentations and discussions, has proved the most successful form of continuing medical education in community hospitals. Better than half the doctors in the community attend, and active participation is the rule. The importance of advance planning, the techniques of advance planning, and the expense of operating the program are listed. A projection is made that 46 such courses would be required to cover the four Atlantic Provinces adequately, with a staff equivalent to eight full-time teachers and a budget in excess of $200,000. The fact that this is only 7.5% of Canada''s medical population indicates the magnitude of the unmet needs of continuing medical education in this country. 相似文献
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149.
Influences of salinity on the physiology and distribution of the Arctic coralline algae,Lithothamnion glaciale (Corallinales,Rhodophyta) 下载免费PDF全文
Kathryn M. Schoenrock Marion Bacquet Danni Pearce Brice R. Rea J. Edward Schofield James Lea Doug Mair Nicholas Kamenos 《Journal of phycology》2018,54(5):690-702
In Greenland, free‐living red coralline algae contribute to and dominate marine habitats along the coastline. Lithothamnion glaciale dominates coralline algae beds in many regions of the Arctic, but never in Godthåbsfjord, Greenland, where Clathromorphum sp. is dominant. To investigate environmental impacts on coralline algae distribution, calcification and primary productivity were measured in situ during summers of 2015 and 2016, and annual patterns of productivity in L. glaciale were monitored in laboratory‐based mesocosm experiments where temperature and salinity were manipulated to mimic high glacial melt. The results of field and cold‐room measurements indicate that both L. glaciale and Clathromorphum sp. had low calcification and photosynthetic rates during the Greenland summer (2015 and 2016), with maximum of 1.225 ± 0.17 or 0.002 ± 0.023 μmol CaCO 3 · g?1 · h?1 and ?0.007 ±0.003 or ?0.004 ± 0.001 mg O2 · L?1 · h?1 in each species respectively. Mesocosm experiments indicate L. glaciale is a seasonal responder; photosynthetic and calcification rates increase with annual light cycles. Furthermore, metabolic processes in L. glaciale were negatively influenced by low salinity; positive growth rates only occurred in marine treatments where individuals accumulated an average of 1.85 ± 1.73 mg · d?1 of biomass through summer. These results indicate high freshwater input to the Godthåbsfjord region may drive the low abundance of L . glaciale , and could decrease species distribution as climate change increases freshwater input to the Arctic marine system via enhanced ice sheet runoff and glacier calving. 相似文献
150.
Marine Telemetry and the Conservation and Management of Risk to Seal Species in Canada and Australia
Julia Jabour Mary-Anne Lea Simon D. Goldsworthy Graeme Melcher Katie Sykes Mark A. Hindell 《Ocean Development & International Law》2016,47(3):255-271
Marine telemetry expands the knowledge of the biology of marine species at risk: their life cycles, activities, interactions, habitats, and threats. Four seal species in Canada and Australia are faced with distinctive and divergent management problems. This article examines their conservation status, legal protection, and the role that telemetry has played, or could play, in providing previously unavailable information to help meet conservation goals. The value of telemetry data to minimize fisheries mortality of one species has been demonstrated in Australia. Despite there being significant telemetry data for the other species, policy and management have not yet responded. 相似文献