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81.
82.
回妮 《北京体育大学学报》2007,30(12):1677-1678
根据药品管理的理论及法规,结合北京体育大学校医院的特点,探讨了高等体育院校校医院药品管理的特点,认为:药品具有特殊用途,并且是治疗的重要工具之一,药品管理应该把握好购药原则与规划,利用各种手段完善药库管理,把握好不同药品的管理,更好的满足教职员工和学生的医疗需要. 相似文献
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以电技术、电子技术类为例,通过对《科图法》第二版和第三版73大类类目的逐条对照与研究,阐述了《科图法》第三版的优点,并对存在的问题提出了修改意见。 相似文献
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87.
The Xizang (Tibetan) flora with numerous endemics is of importance in Chi-
nese flora. According to recent statistics there are in Xizang 27 genera of spermatophytes
endemic to China, being only 2.25% percent of the total number of genera in the Xizang flora.
Four of them are regarded as palaeoendemics (14.81%) and the others as neoendemics (85.19%).
These endemic genera, of 30 species and 3 varieties, belong to 17 families, of which, Umbelli-
ferae contains 6 genera, 7 species and 3 varieties; Compositae has 6 genera and 7 species, and
Gentianaceae 1 genus and 2 species. All the other families each comprises one genus with a
single species.
The cosmopolitan families together comprising 14 genera with 15 species have the highest
perecentage (52.92%) and the tropical ones (5 families, 5 genera with 5 species) come to the next
(29.42%), followed by the temperate ones (3 families, 10 genera with 10 species) (17.66%). It
shows that these endemic genera are obviously related to the tropical flora and temperate one
in essence.
According to the number of species, the genera endemic to China and occurring in Xi-
zang flora may be grouped as fallows.
Monotypic endemic ones 14 (51.85%)
Ditypic endemic ones 6 (22.22%)
Oligotypic endemic ones 4 (14.81%)
Small endemic ones 3 (11.11%)
The formation of the endemic genera is correlated with the topography, climate and en-
vironmental conditions, and they may have resulted from the diversification in geography and
climatic influence for a long time. The southeastern part of Xizang Plateau is of very diverse
ecological conditions, with the adequate precipitation, which may explain the concentration of
these endemic genera in this region.
The largest similarity coefficient (38.30%) of the genera endemic to China and occurring
in Xizang is with those in Qinghai Plateau, next, with those in Yunnan and in Sichuan pro-
vinces (both 27.60%), which shows that these endemic genera are related to the floras of the
regions mentioned above.
The difference in the horizontal distribution of these endemic genera is obviously between
the southern and northern parts of Xizang Plateau. The vertical distribution of the genera is
also rather obvious, from 800 m to 5200 m above sea level, but concentrated in the zone of 3000
m to 4500 mm. Therefore their occurrence in Xizang is not only affected by the historical
environmental conditions but also controlled by the horizontal and vertical distribution.
The origin and evolution of some endemic genera, such as Psammosilene, Parateropyrum,
Sphaerotylos, Salweenia, Ajaniopsis, Xizangia, Sinoleontopodium, are discussed in this paper.
Parateropyrum, a monotypic palaeotropic endemic, belongs to the tribe Atraphaxideae in-
cluding Atraphaxis, Calligonum and Pteropyrum. It may be a comparatively advanced group
in the tribe, and is closely related to the genus Pteropyrum which is distributed in western
Asia. The genus Parapteropyrum has possibly survived as a palaetropic-tertiary relic in this
region.
Sphaerotylos, a member of the subtribe Sphaerotylinae, the tribe Boehmerieae in the family
Urticaceae, is a comparatively primitive genus in the tribe Boehmerieae so far known. As the
other subtribes, such as Boehmerinae, Sarconchlamydinae, Orecnidinae and Maoutinae, are dis-
tributed in the tropics, rarely in the subtropics, the genus is no doubt a palaetropic -tertiary
relic.
Sinoleontopodium, belonging to the tribe lnuleae in Compositae, is also related to the ge-
nus Leontopodium. It is probable that the genus Sinoleontopodium arised later than the other.
We come to the conclusion that the southern part of Xizang Plateau is also one of thecentres of the origin and differentiation of genera endemic to China. 相似文献
88.
89.
简述了文献计量学和引文分析对图书情报工作的作用;阐明对我国天文学期刊引文统计分析的目的;提出一般引文统计的原则;介绍了这次引文统计所涉及的内容。其中包括:(1)文献老化的量度——中国天文学近6年文献的半衰期和D.Price指数值;(2)天文学期刊引文率按年代分布的特征;(3)引文按语种分布比例;(4)引文按不同时间段反映出天文系统科技人员利用文献资料的引用率,(5)引文按文献类型统计结果;(6)篇引率及与国外同类刊物的比较。最后引出了对天文学期刊引文统计结果分析的6点认识。 相似文献
90.
振兴海峡西岸经济区的区域化经济,科技信息资源是关键。为此,提出创建海峡两岸科技信息资源共享,促进海峡西岸经济区的崛起和台湾经济的共同发展。 相似文献