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排序方式: 共有10000条查询结果,搜索用时 15 毫秒
911.
This study investigates the contribution of body fat stores on the age-associated increase in serum cholesterol and triglyceride levels. Percentage of body fat was measured by hydrostatic weighing, and serum cholesterol, triglyceride, low-density lipoprotein cholesterol, and high-density lipoprotein cholesterol levels were determined in a sample of 472 healthy men and women ages 18-50 years. In both sexes, body fat mass was significantly correlated with serum cholesterol (r = 0.21 in men and r = 0.24 in women, P less than 0.01) and triglyceride (r = 0.33 in men and r = 0.24 in women, P less than 0.01) levels. After adjustment for the association between age and serum cholesterol, no correlation was observed between body fat mass and serum cholesterol (r = 0.01 in men and r = 0.09 in women). After correction for age, serum triglyceride levels remained significantly correlated with body fat mass (r = 0.26 and r = 0.17 in men and women, respectively, P less than 0.05). As body fat also increases with age, the possibility that a partial correlation coefficient procedure eliminated a portion of the age effect mediated by an age-related increase in fat, was addressed by performing further analyses. Within each sex subsample two sets of analyses were performed on (a) three groups of subjects individually paired for age but with different levels of body fat stores, and (b) three groups of subjects paired for the amount of body fat but differing in age.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
912.
Jay Magaziner Eleanor M. Simonsick T. Michael Kashner J. Richard Hebel 《Journal of clinical epidemiology》1988,41(11)
The present study evaluates the response comparability between 361 elderly hip fracture patients admitted from the community to seven Baltimore area hospitals between 1984 and 1986 and interviewer selected proxies on items pertaining to patients' pre-fracture health and functional status. Agreement across items ranges from very poor to good and varies with respect to the health or functional area assessed. Proxies tend to overestimate patient disability relative to the patients themselves, especially with regard to capacity to perform instrumental activities of daily living. Although proxies who report the greatest contact with patients respond most comparably to the patients, when they do disagree, proxies with the greatest patient contact tend to overestimate patient disability. The authors suggest that attention to item construction and phrasing may improve response comparability. 相似文献
913.
This article reports on a longitudinal qualitative study ofthe psychosocial factors influencing women's experience of breastfeeding.The findings illustrate the complex web of factors, both personaland environmental, that influence breastfeeding behaviour. Thesignificance of breastfeeding derives from the fact that it,in concert with the arrival of a new baby, heralds significantchanges in a woman's day-to-day life. Three major areas of change,in part precipitated by breastfeeding, were critical. Theseinclude changes in the amount of time available to the motherand the nature of the activities that fill this time, changesin a woman's body due to pregnancy and breastfeeding, and changesin the nature of a woman's personal needs. These changes constitutea substantial and often disconcerting shift in lifestyle. Thearticle examines the potential consequences of these changesfor the mother and the host of mediating factors that influenceher response to them and hence to breastfeeding. The mediatingfactors include the personal and psychological factors relatedto the attitudes, values and character traits of the mother,baby, and those close to them. Others are structural factorssuch as the absence or presence of formal and informal supportsystems that range from paid maternity leave to community drop-incentres, educational programmes, and community parks. They alsoinclude the host of cultural factors that influence the waysin which individuals and society view breastfeeding. 相似文献
914.
Oil-emulsified (OE) and aqueous (Aq) vaccines were prepared with the same batch of inactivated A24 8345 foot and mouth disease virus (FMDV). Calves born to vaccinated dams did not respond to the Aq vaccine 30 or 90 days post partum. When the OE vaccine was used on a similar group of calves, no responses were elicited up to 21 days post partum. However, calves 30 or more days old responded like adult cattle to the OE vaccine. When the OE vaccine was used in colostral antibody-free calves 3-30 days old, all animals showed good antibody responses but, in calves vaccinated 3 or 7 days post partum, antibodies were detectable only after a considerable period of time. Our results show that both passively acquired colostral antibodies and age are important in the response of very young calves to FMDV oil vaccines. From a practical point of view, in endemic areas where adult cattle are periodically vaccinated, vaccination of calves between 30 and 60 days post partum with OE vaccines would lead to high levels of herd protection. 相似文献
915.
M J Buxton 《Health services management research》1988,1(1):43-50
Rapidly advancing health technology poses problems for managers. Although clear conceptual frameworks exist for economic evaluation, in practice severe problems remain in carrying out timely research that is locally appropriate to the needs of managers. This paper explores some of these problems in the context of the policy analysis interface between economic research and the management of technology. In the light of experience gained from recent evaluation research it indicates how researchers and managers can each contribute to the provision of a stronger empirical basis for policy making and policy management. An earlier version of this paper was presented at the joint meeting of the Health Economists Study Group and Institute of Health Service Management, University of York, 6-8 July 1987. The author would like to thank Christopher Spry and Mike Drummond for helpful comments. 相似文献
916.
Relation between energy expenditure and body composition in man: specific energy expenditure in vivo of fat and fat-free tissue 总被引:2,自引:0,他引:2
L Garby J S Garrow B J?rgensen O Lammert K Madsen P S?rensen J Webster 《European journal of clinical nutrition》1988,42(4):301-305
The relationship between energy expenditure and body composition, in terms of fat and fat-free masses, has previously been described by a variety of predictive regression equations with parameters devoid of physiological content. We present here results obtained by calculating the specific energy expenditure, ie, the energy expenditure per unit of mass, of fat and fat-free tissue on the basis of measurements of the total energy expenditure (EE), the masses of fat (FM), and fat-free (FFM) tissue using the following simple model: EE = k1.FM + k2.FFM where k1 and k2 are the specific energy expenditures of fat and fat-free tissue, respectively. The results of observations on 104 women at rest yielded values for k1 and k2 of 0.31 and 1.35 watts/kg of fat and fat-free mass, respectively, with standard errors of estimate of 0.074 and 0.052 watts/kg, respectively. Analysis of several series of measurements, from other sources and on smaller samples of subjects, yielded similar values at rest but with larger standard errors of estimate. Data from subjects performing varying amounts of work in 24-h measurements showed, as expected, larger values for both tissues. The results explain to a very large extent the well-established relation between resting metabolic rate and body weight, ie, a linear relation with a non-zero intercept. The results also offer a clear-cut explanation for the well known difference in energy expenditure between men and women with the same body weight. 相似文献
917.
K S Shiba K Kanamori H Cho N Furuhata T Harada A Shiba M Nakao 《Clinica chimica acta; international journal of clinical chemistry》1988,172(1):77-84
Proteins in normal human urine were clearly fractionated into 26 bands with molecular weights from 14,000 to 230,000 by means of one-dimensional sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) coupled with silver staining. The main band contained uromucoid, and the second main band had albumin. However, when urine samples from healthy persons were electrophoresed in the absence of SDS using polyacrylamide gel or agarose gel, or a cellulose acetate membrane, albumin but not uromucoid, frequently formed the main protein band. It is suggested that this is due to the complexing of uromucoid subunits to form a large molecule which cannot penetrate into the gel. In order to correctly fractionate all the proteins contained in normal human urine, it was concluded that it was best to treat a urine sample with SDS with pre-condensation, fractionate it by SDS-PAGE and stain fractionated proteins by a highly sensitive method such as silver staining. 相似文献
918.
Reevaluation of procarbazine for the treatment of recurrent malignant central nervous system tumors 总被引:1,自引:0,他引:1
Ninety-nine patients with primary recurrent malignant tumors of the central nervous system were treated with procarbazine as a single agent. Procarbazine was not given as a specified protocol, but for patients who were ineligible or refused other protocols. All patients had been treated previously with radiotherapy and 96 patients had also received previous chemotherapy. Twenty-five patients were treated at the first progression of their tumor, 47 were treated at the second progression, and 27 were treated at the third progression of their tumor. For the aggregate, the response plus stabilization rate was 27% for glioblastoma multiforme with median time to tumor progression of 30 weeks, and 28% for other anaplastic gliomas with a median time to tumor progression of 49 weeks. With respect to the percent of patients who responded or stabilized to treatment, these results are inferior to those reported previously for patients treated with procarbazine at recurrence. With respect to duration of response and stabilization, the data are comparable. 相似文献
919.
During recent decades there has been a controversial discussion if comparable plasma level profiles which are rather constant or those which show a high peak are more efficient for the cure of gonorrhoea. So far, investigations in this field were not based on the Grasso apparatus. Although the findings with cefotiam and ceftizoxime do not allow to formulate a general hypothesis without any restriction, it can be stated that on the basis of an identical area under the antibiotic level time curve, 'peak concentration' profiles are more favourable. 相似文献
920.
Factors associated with the quality of laboratory performance in the United Kingdom external quality assessment scheme for serum growth hormone 总被引:1,自引:0,他引:1
J Seth I Hanning 《Clinica chimica acta; international journal of clinical chemistry》1988,174(2):185-195
A search was made for associations between poor performance in the UK External Quality Assessment Scheme (EQAS) for serum growth hormone (GH), and a range of factors including assay method, laboratory workload and staffing, and Internal Quality Control (IQC) procedures. On the basis of the factors identified as being associated with poor performance we recommend the following. 1. Laboratories using RIA for GH should routinely analyse samples at two dilutions and report a mean result. 2. The use of 125I-GH which is 5 or more weeks old should be avoided. Tracer should also be chromatographed to remove aggregate before use. 3. Laboratories using RIA should avoid using a standard curve which covers too wide a range concentration; a curve midpoint (ie GH concentration to reduce the zero standard binding by 50%) of about 8 mU/l or less is probably acceptable. 4. It should be noted that high workloads present a risk of some loss in quality of responsible for checking IQC data. 6. Laboratories which do not have the resources to maintain fully their own RIA as outlined above should carefully consider use of an unbiased, precise IRMA. The UK EQAS has identified two assays (Boots-Celltech Sucrosep, NETRIA) that appear to meet these criteria [2]. The above observations may also be relevant to immunoassays for other peptide hormones. 相似文献