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BACKGROUND: By 2016, the proportion of Canadians older than 65 years of age will increase to 16%, and there will be an increase in the absolute number of cases of cardiovascular disease in older Canadians. The Canadian Heart Health Surveys database provides information about this population upon which health policy related to cardiovascular disease can be based. This paper presents for the first time population-based data on the risk factors for cardiovascular disease in older Canadians. METHODS: Canadians from all 10 provinces participated in surveys of cardiovascular risk factors; health insurance registries were used as sampling frames. In each province, probability samples of 2200 adults 18 to 74 years old not living in institutions, on reserves or in military camps were asked to participate in interviews and to undergo testing at clinics for major risk factors for cardiovascular disease. RESULTS: A total of 2739 men (response rate 70%) and 2617 women (response rate 66%) aged 55 to 74 years participated in the survey and also provided follow-up clinical measurements at the clinic. Overall, 52% of participants were hypertensive, 26% had isolated systolic hypertension, and 30% had a total blood cholesterol level of 6.2 mmol/L or greater. Rates of current smoking were lower in women than men (17% v. 22%). Overall, 87% of men and 78% of women who were current smokers smoked at least 10 cigarettes per day. Only slightly more than half of participants exercised at least once a week for at least 15 minutes, and almost half had a body mass index of 27 or greater. In only 4% was no major risk factor for cardiovascular disease detected. INTERPRETATION: Significant numbers of older Canadians have one or more major risk factors for cardiovascular disease. Many of these risk factors are amenable to modification. 相似文献
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Coevolution of the glucose dehydrogenase gene and the ejaculatory duct in the genus Drosophila 总被引:2,自引:0,他引:2
The glucose dehydrogenase gene (Gld) in Drosophila melanogaster exhibits a
unique spatial and temporal pattern of expression. GLD expression switches
from a non-sex-limited state at the pupal stage to a male-limited state at
the adult stage. At the adult stage, the enzyme is restricted to the
ejaculatory duct. Within the genus Drosophila, the ejaculatory duct has
undergone a simple morphological divergence. In order to determine whether
correlated changes in GLD expression had occurred, GLD activity during the
pupal and adult stages was determined for several Drosophila species. It
was found that virtually all of the species exhibit pupal GLD activity,
whereas only those species with an expanded ejaculatory duct express
male-limited GLD. The results of interspecific genital imaginal disc
transplantation experiments indicate that the expanded morphology and GLD
expression do not require any species- or sex-specific diffusible factors.
An apparent regulatory polymorphism exists within the D. takahashii species
with respect to male-limited GLD expression.
相似文献
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DR. Myron A. Mehlman DR. Emil A. Pfitzer DR. Robert A. Scala The Committee to Promote Principles of Reduction Refinement Replacement of Animal Testing in Industrial Toxicology Laboratories 《Cell biology and toxicology》1989,5(3):349-358
The Committee to Promote Principles of Reduction, Refinement and Replacement of Animal Testing in Industrial Toxicology Laboratories was established in 1987 to work toward industrywide improvements in laboratory animal testing methods. The committee's goals are to gather information about effective nonanimal testing techniques and other methods of conserving and improving the care of laboratory animals, to work toward the systematic validation of nonanimal alternatives, and to disseminate useful information about progressive programs and policies throughout the industrial toxicology community. This is the first in a continuing series of reports the committee plans to produce as part of an ongoing program to promote communication among industrial toxicologists about successful methods of reducing, refining and replacing animal testing. Here are some of the report's major findings: (1) Animal care and use committees charged with the oversight of laboratory animal use are a universal practice at the companies surveyed. (2) Significant reductions in the number of animals used for acute toxicity testing have taken place at all the companies during the last 5- to 10-year period. (3) Structure-activity relationships (predicting a test compound's properties based on the known properties of familiar chemicals with similar structures) are widely used to minimize, but not replace, the use of animals. (4) Tissue and organ culture systems are being used with increasing frequency for screening and mechanistic studies, but are not completely replacing animal evaluations as a final step. (5) There is a pressing need for the systematic and scientifically sound validation of nonanimal alternative techniques to reduce the use of animals in toxicology testing while satisfying requirements for the protection of public safety. 相似文献
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Background
Biological experiments increasingly yield data representing large ensembles of interacting variables, making the application of advanced analytical tools a forbidding task. We present a method to extract networks of correlated activity, specifically from functional MRI data, such that: (a) network nodes represent voxels, and (b) the network links can be directed or undirected, representing temporal relationships between the nodes. The method provides a snapshot of the ongoing dynamics of the brain without sacrificing resolution, as the analysis is tractable even for very large numbers of voxels.Results
We find that, based on topological properties of the networks, the method provides enough information about the dynamics to discriminate between subtly different brain states. Moreover, the statistical regularities previously reported are qualitatively preserved, i.e. the resulting networks display scale-free and small-world topologies.Conclusion
Our method expands previous approaches to render large scale functional networks, and creates the basis for an extensive and -due to the presence of mixtures of directed and undirected links- richer motif analysis of functional relationships.50.
DR Suresh Vamseedhar Annam K Pratibha BV Maruti Prasad 《Journal of biomedical science》2009,16(1):61-4