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991.
The refractoriness of guinea-pigs to the growth-promoting actions of exogenous GH has been suggested to be due to a deficiency or defect in tissue GH receptors or in GH-receptor gene expression. GH-receptor mRNA was, however, demonstrated by Northern blot analysis and by the polymerase chain reaction in extracts of guinea-pig liver, adipose tissue, brain, hypothalamus and pituitary gland. High-affinity, low-capacity binding sites for radio-labelled ovine GH were also demonstrated on the plasma membranes of guinea-pig liver and were similar to those in rat liver. These results demonstrate that the unresponsiveness of guinea-pigs to exogenous GH is not due to the absence of GH receptors. 相似文献
992.
Down''s syndrome: prevalence and ionising radiation in an area of north west England 1957-91. 总被引:2,自引:0,他引:2 下载免费PDF全文
OBJECTIVE--To analyse the prevalence of Down's syndrome in a specific, geographical area and seek to explain variations with particular reference to ionising radiation. DESIGN--Cases were ascertained by one paediatrician as part of a prospective survey of major congenital malformations in children born to residents of an area of Lancashire between 1957 and 1991. Temporal changes in prevalence rates were detected by a grid search technique using Poisson log linear models. These models were also used to determine the association between prevalence and ionising radiation from atomic fall out. SETTING--The Fylde district of Lancashire in the north west of England. PATIENTS--There were 167 cases, including five stillbirths and eight terminations, among 124,015 total births in a population which increased from about 250,000 to over 300,000 during the study period. MAIN RESULTS--There was significant increase in the prevalence of all cases conceived in 1963 and 1964, and a lesser peak in 1958 which did not quite reach statistical significance. There was no evidence that the increased prevalence in 1963-64 was a result of changes in the maternal age distribution in the population. Babies of mothers aged 35 years and over accounted for more of the variation, especially in 1958 when their increase was significant. There was a highly significant association between prevalence and radiation from fallout produced by atmospheric testing of atomic weapons. The 1963-64 peak coincided with the maximum estimated radiation dose. The lesser peak in 1958 also coincided with increased exposure to radiation from fallout, possibly enhanced by ground deposits after a fire at the Windscale reactor in October 1957. CONCLUSION--This study provides further support for low dose ionising radiation as one aetiological factor in Down's syndrome. 相似文献
993.
Kearns-Sayre syndrome (KSS) is a form of mitochondrial myopathy in which specific clinical features, namely progressive external ophthalmoplegia, pigmentary retinal degeneration and cardiac conduction defects, occur. KSS has also been associated with a variety of endocrine and metabolic disorders, in particular short stature, gonadal failure, diabetes mellitus, thyroid disease, hyperaldosteronism, hypomagnesaemia, and bone, tooth and calcification abnormalities. A case is described exhibiting all of these features. A survey of the literature was conducted to determine the prevalence of these conditions among reported cases. Cases with hypoparathyroidism were considered separately to see if they constituted a distinct subgroup with multiple endocrine dysfunction.
Short stature was common, being documented in 38% of cases. Gonadal dysfunction before or after puberty was also common (20% of cases) and affected both sexes equally. Diabetes mellitus was recorded in 13% of cases, half of which required insulin. Thyroid disease, hyperal-dosteronism and hypomagnesaemia were uncommon but were probably not looked for in many cases. Bone or tooth abnormalities and calcification of the basal ganglia were found both in those with and without hypoparathyroldism. While endocrine and metabolic dysfunction was found more commonly in those with hypoparathyroldism this is likely to be due to increased recognition rather than increased prevalence. No evidence of an autoimmune polyendocrine syndrome including hypoparathyroldism was found. 相似文献
Short stature was common, being documented in 38% of cases. Gonadal dysfunction before or after puberty was also common (20% of cases) and affected both sexes equally. Diabetes mellitus was recorded in 13% of cases, half of which required insulin. Thyroid disease, hyperal-dosteronism and hypomagnesaemia were uncommon but were probably not looked for in many cases. Bone or tooth abnormalities and calcification of the basal ganglia were found both in those with and without hypoparathyroldism. While endocrine and metabolic dysfunction was found more commonly in those with hypoparathyroldism this is likely to be due to increased recognition rather than increased prevalence. No evidence of an autoimmune polyendocrine syndrome including hypoparathyroldism was found. 相似文献
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995.
Periodontal diseases in Africa 总被引:1,自引:0,他引:1
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J. David Dahm Donald G. Sessions Randal C. Paniello Joseph Harvey 《The Laryngoscope》1998,108(5):741-746
This retrospective study reviews 39 patients with primary subglottic cancer seen between 1955 and 1988 by the Department of Otolaryngology at Washington University. This number constitutes 1.8% of laryngeal cancer cases diagnosed during this period. Twenty-eight patients (71.8%) had epidermoid cancer, of which 19 (67.9%) had “early” disease (stages I and II), and nine (32.1%) had “advanced” (stages III and IV). Overall 5-year survival was 57.7%. Disease-free survival was 46.2%. Patients treated with radiotherapy alone, surgery alone, or both had disease-free 5-year survivals of 22.2%, 41.7%, and 100%, respectively. Combination therapy showed a significantly higher (P < .01) disease-free survival than radiotherapy alone. 相似文献
1000.
This paper proposes a model of the relationship between values, in particular health value, and adjustment to illness. The importance of values as well as the need for value change are described in the literature related to adjustment to physical disability and chronic illness. An empirical model, however, that explains the relationship of values to adjustment or adaptation has not been found by this researcher. Balance theory and its application to the abstract and perceived cognitions of health value and health perception are described here to explain the relationship of values like health value to outcomes associated with adjustment or adaptation to illness. The proposed model is based on the balance theories of Heider, Festinger and Feather. Hypotheses based on the model were tested and supported in a study of 100 adults with visible and invisible chronic illness. Nursing interventions based on the model are described and suggestions for further research discussed. 相似文献