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The first call for applications to the NHS research and development programme on the interface between primary and secondary care was advertised in February 1994. A total of 674 outline proposals were submitted and 54 (8%) secured funding. Projects have been commissioned in 16 of the 21 priority areas and around 6m pounds has been committed. Analysis shows that multidisciplinary applications are more likely to be funded and that the odds for a successful application are on average nearly doubled for each discipline represented up to five. A survey of applicants and peer reviewers found satisfaction with much of the commissioning process, but peer review and feedback were subject to criticism, particularly by unsuccessful applicants. The programme shows that it is possible to commission a large number of projects in an innovative area of research and development and has identified refinements that will further increase the efficiency and acceptability of the process. 相似文献
35.
B. L. Haines 《Oecologia》1977,26(4):295-303
Summary Nitrogen uptake from applied nutrient solutions was evaluated in two old fields, in a pine plantation, and in a hardwood stand, to test the idea that plant communities become more efficient trappers and retainers of plant nutrients during succession. Uptake was estimated as the difference between nutrient concentrations in water collected from beneath soil profiles with and without roots by lysimeters within each successional stage. Results suggest that nitrate uptake decreased while ammonia uptake increased with succession. This apparent shift from a nitrate to an ammonia nitrogen economy during succession has been reported by other workers and is evolutionarily significant as an energy, nitrogen, and cation saving mechanism. 相似文献
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NH4+ and NO3? uptake were measured by continuous sampling with an autoanalyzer. For Hypnea musciformis (Wulfen) Lamouroux, NO3?up take followed saturable kinetics (K2=4.9 μg-at N t?1, Vmax= 2.85 μg- at N, g(wet)?1. h?1. The ammonium uptake data fit a trucatd hyperbola, i.e., saturation was not reach at the concentrations used. NO3? uptake was reduced one-half in the presence of NH4+, but presence of NO3? had no effect on NH4+ uptake. Darkness reduced both NO3? and NH4+ uptake by one-third to one-half. For Macrocystis pyrufera (L) C. Agardh, NO3? uptake followed saturable kinetices: K2=13.1 μg-at N. l?1. Vmax=3.05 μg-at N. g(wet)?1. h?1.NH4+ uptake showed saturable kinetics at concentration below 22 μg-at N l -1 (K2=5.3 μg-at N.1–1, Vmax= 2.38 μg-at N G (wet)?1.h?1: at higher concentration uptake increased lincarly with concentrations. NO3?and NH4+ were taken up simulataneously: presence of one form did not affect uptake of the other. 相似文献
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The investigation of several South African species of the tribe Inuleae afforded in addition to known compounds 16 new constituents. From Leontonyx a group of 9 new phloroglucinol derivatives, from Stoebe species two new p-hydroxyacetophenone, two thymol and two coumaric acid derivatives and from Relhania a new euparine-derivative were isolated. The structures are elucidated mainly by spectroscopic methods. The chemotaxonomic aspects are discussed briefly. The phloroglucinol derivatives, which in part are derived from geraniol, seem to be especially characteristic. 相似文献
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Flanking markers bracket the neurofibromatosis type 2 (NF2) gene on chromosome 22. 总被引:8,自引:4,他引:4 下载免费PDF全文
G A Rouleau B R Seizinger W Wertelecki J L Haines D W Superneau R L Martuza J F Gusella 《American journal of human genetics》1990,46(2):323-328
Neurofibromatosis 2 or bilateral acoustic neurofibromatosis (NF2) is a severe autosomal dominant disorder characterized by the development of multiple tumors of the nervous system, including meningiomas, gliomas, neurofibromas, ependymomas, and particularly acoustic neuromas. Polymorphic DNA markers have revealed frequent loss of one copy of chromosome 22 in the tumor types associated with NF2. Family studies have demonstrated that the primary defect in NF2 is linked to DNA markers on chromosome 22, suggesting that it involves inactivation of a tumor suppressor gene. We have employed a combination of multipoint linkage analysis and examination of deletions in primary tumor specimens to precisely map the NF2 locus between flanking polymorphic DNA markers on chromosome 22. The 13-cM region bracketed by these markers corresponds to 13% of the genetic length of the long arm of chromosome 22 and is expected to contain less than 5 x 10(6) bp of DNA. The delineation of flanking markers for NF2 should permit accurate presymptomatic and prenatal diagnosis for the disorder and greatly facilitate efforts to isolate the defective gene on the basis of its location. 相似文献
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Ferdinand Bohlmann Antoinette Suwita Jasmin Jakupovic Robert M. King Harold Robinson 《Phytochemistry》1981,20(7):1649-1655
The investigation of two further Trixis species afforded five new sesquiterpenes related to trixikingolide, six new germacrene derivatives and a sesquiterpene derived from rotundene. Some further known compounds were isolated too, which in part may be of chemotaxonomic significance. The structures were elucidated by spectroscopic methods and a few chemical transformations. The relative position of the ester groups in eight of the new sesquiterpenoids however, could not be established with certainty as partial saponifications were not successful. 相似文献