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排序方式: 共有171条查询结果,搜索用时 15 毫秒
41.
Di Zhang Vincent H. Ng Zhaochen Wang Xiaomei Zhai Reidar K. Lie 《Developing world bioethics》2016,16(2):107-115
The application of genetic technologies in China, especially in the area of prenatal genetic testing, is rapidly increasing in China. In the wealthy regions of China, prenatal genetic testing is already very widely adopted. We argue that the government should actively promote prenatal genetic testing to the poor areas of the country. In fact, the government should prioritize resources first to make prenatal genetic testing a standard routine care with an opt‐out model in these area. Healthcare professions would be required to inform pregnant women about the availability of genetic testing and provide free testing on a routine basis unless the parents choose not to do so. We argue that this proposal will allow parents to make a more informed decision about their reproductive choices. Secondarily, this proposal will attract more healthcare professionals and other healthcare resources to improve the healthcare infrastructures in the less‐developed regions of the country. This will help to reduce the inequity of accessing healthcare services between in different regions of China. We further argue that this policy proposal is not practicing eugenics. 相似文献
42.
The membrane systems of the cardiac muscle cell of Munida tenuimana G. O. Sars are described. The sarcolemma invaginates at the Z level, forming tubules. Narrow tubules branch off in a longitudinal direction from these transverse and radially arranged tubules, forming a narrow transverse collar at the H level where dyadic and triadic junctions are formed with the sarcoplasmic reticulum. 相似文献
43.
A morphological analysis of the Scandinavian mountain endemic Draba cacuminum Elis. Ekman is presented, based on Scandinavian herbarium collections and a population sample from the Finse area, S Norway. It is compared with supposedly close relatives, especially D. norvegica Gunnerus, and is found to be a distinct species with infraspecies variation at two levels. The populations of southern and northern Scandinavia have been separated as subspecies, ssp. cacuminum and ssp. angusticarpa Elven ssp. nov., respectively, and there is also variation within the southern subspecies. A lectotype has been chosen for D. cacuminum , a revised distribution map is presented, and the ecology and phytogeography of the species is discussed. It seems to be a weak competitor, and its present very discontinuous area is assumed to be a remnant of one continuous or more probably two areas (in S Norway and N Scandinavia) in the late Weichselian. 相似文献
44.
Dr. Thv. Selmer Sætersdal Eli Sørensen Reidar Myklebust Karen B. Helle 《Cell and tissue research》1975,163(4):471-490
The concentrations of catecholamines in the heart chambers of elasmobranchs were measured by the fluorimetric method of Bertler et al. (1958). Noradrenaline (NA) can be detected in all the chambers, but the sinus venosus is by far the richest in NA. This can either be due to the presence of storage sites for this amine in the sinus wall, or to a transport of amine to the sinus venosus from the anterior chromaffin bodies. The sinus wall contains large numbers of "granule containing cells" and axon-like processes, both with numerous dense-core vesicles of about 1800 A diameter. The dense-core vesicles contain a uranophilic matrix indicating the presence of protein, phospholipids and/or nucleic acid. The reactions failed to demonstrate amine, which may be due to a loss of amine by diffusion, to a relatively low intravesicular amine concentration, or, to the absence of amines in these granule-containing cells and processes. Heavy accumulations of granule-containing processes occur in the subendothelial area. The endothelium contains fenestrae and pores through which granule-containing fibres protrude into the venous cavity. Granule-containing cells are innervated by presumed cholinergic nerve endings. It is suggested that the granule-containing cells and fibres belong to the neurosecretory system with a cholinergic input, releasing the contents of the dense-core vesicles into the blood stream at the level of the venous cavity. 相似文献
45.
Rune Ehrenreich Kuhre Charlotte Bayer Christiansen Seyed Mojtaba Ghiasi Maria Buur Nordskov Gabe Patricia Almine Skat-Rørdam Ida Marie Modvig Thomas Mandrup-Poulsen Reidar Albrechtsen Mette Marie Rosenkilde Bolette Hartmann Nicolai Jacob Wewer Albrechtsen Jens Juul Holst 《Cell metabolism》2019,29(3):719-726.e5
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48.
Population characteristics predict responses in moose body mass to temporal variation in the environment 总被引:2,自引:0,他引:2
Herfindal I Saether BE Solberg EJ Andersen R Høgda KA 《The Journal of animal ecology》2006,75(5):1110-1118
1. A general problem in population ecology is to predict under which conditions stochastic variation in the environment has the stronger effect on ecological processes. By analysing temporal variation in a fitness-related trait, body mass, in 21 Norwegian moose Alces alces (L.) populations, we examined whether the influence of temporal variation in different environmental variables were related to different parameters that were assumed to reflect important characteristics of the fundamental niche space of the moose. 2. Body mass during autumn was positively related to early access to fresh vegetation in spring, and to variables reflecting slow phenological development (low June temperature, a long spring with a slow plant progression during spring). In contrast, variables related to food quantity and winter conditions had only a minor influence on temporal variation in body mass. 3. The magnitude of the effects of environmental variation on body mass was larger in populations with small mean body mass or living at higher densities than in populations with large-sized individuals or living at lower densities. 4. These results indicate that the strongest influence of environmental stochasticity on moose body mass occurs towards the borders of the fundamental niche space, and suggests that populations living under good environmental conditions are partly buffered against fluctuations in environmental conditions. 相似文献
49.
Clinical ethics committees have recently been established in nearly all Norwegian hospital trusts. One important task for these committees is clinical ethics consultations. This qualitative study explores significant barriers confronting the ethics committees in providing such consultation services. The interviews with the committees indicate that there is a substantial need for clinical ethics support services and, in general, the committee members expressed a great deal of enthusiasm for the committee work. They also reported, however, that tendencies to evade moral disagreement, conflict, and 'outsiders' are common in the hospitals. Sometimes even the committees comply with some of these tendencies. The committees agree that there is a need to improve their routines and procedures, clarify the committees' profile and field of responsibility, to make the committees well-known, to secure adequate operating conditions, and to develop organizational integration and support. Various strategies to meet these challenges on a local, regional or national level are also explored in this paper. 相似文献
50.
Marleen M. P. Cobben John D. C. Linnell Erling J. Solberg Reidar Andersen 《Ecological Research》2009,24(6):1197-1205
The survival rates and body masses of roe deer (Capreolus capreolus) were studied on the island of Storfosna in central Norway in relation to sex, age, season and year. There were no predators
on the island, and hunting was halted during the study period, resulting in a population increase from 10 to 40 individuals
per km2 during the period 1991–1994. A total of 352 individual roe deer were radio-monitored on a monthly basis. Survival rates were
analyzed using the MARK software. An age effect in survival was found separating fawns from yearlings and adults, and for
yearlings and adults we furthermore found a year effect. There was evidence for density dependence in body masses of fawns
and yearlings, but no density effect in survival rates. We found no sex effect in winter body mass, but a significant sex
effect in survival rates. We conclude that (1) increased population density can have an effect on body masses without causing
a change in survival rates (2) roe deer can maintain very high survival rates under favourable environmental conditions even
at very high population densities (3) male adults can reach equally high survival rates as females under favourable circumstances. 相似文献