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991.
Renner CC Patten CA Enoch C Petraitis J Offord KP Angstman S Garrison A Nevak C Croghan IT Hurt RD 《Preventive medicine》2004,38(4):421-431
BACKGROUND: Tobacco dependence interventions developed for Alaska Natives are virtually nonexistent. Alaska Natives residing on the Yukon-Kuskokwim (Y--K) Delta in southwestern Alaska use a unique form of smokeless tobacco (ST) known as Iqmik. This study employed focus group methodology to explore attitudes toward tobacco use and tobacco dependence interventions among Alaska Natives residing on the Y-K Delta. METHODS: Twelve focus groups of former and current tobacco users were conducted in four villages in the Y-K Delta. Participants were 35 adults (83% female) and 22 adolescents (27% female). Participants completed a brief demographic and tobacco use history form. Statements from the focus groups were transcribed for content coding and analysis of the major themes. RESULTS: Use of Iqmik in the villages is thought to be ubiquitous. Y-K Delta Alaska Natives are introduced to Iqmik at a very young age. Iqmik is mostly used and prepared by young Alaska Natives and adult women. There are few perceived adverse health effects of Iqmik or other tobacco use. Although there is interest in stopping, there is a perceived lack of availability of tobacco dependence interventions. The major barriers to preventing the initiation of and stopping tobacco use are the social acceptance and widespread use and availability of tobacco. CONCLUSION: The attitudes toward tobacco and identified barriers to stopping will be useful in developing tobacco dependence interventions for Alaska Natives. 相似文献
992.
Klepac-Pulanić T Macan J Plavec D Kanceljak-Macan B 《Arhiv za higijenu rada i toksikologiju》2004,55(2-3):197-204
The aim of this study was to compare exercise-induced bronchial reaction between healthy control subjects and subjects with allergic rhinitis (AR) and allergic asthma (AA). It included 16 controls, 16 subjects with AR and 19 subjects with AA. A skin prick test, pulmonary function test, histamine challenge test and exercise challenge test (ECT) were performed in all subjects. Bronchial reaction to exercise was expressed as the fall index FEV1 (%), AUC(0-30) (min x %), and fall index FEF(25-75) (%). After ECT, subjects with AA had a significantly greater bronchial reaction to exercise than subjects with AR and controls (respective fall index FEV1 8.4, 2.9, and 2.4%, P=0.0083; AUC(0-30) 127.7, 29.6, and 33.1 min x %, P=0.025; and fall index FEF(25-75) 14.6, 0.06, and 1.9%, P<0.001). No difference was found between subjects with AR and controls. In conclusion, ECT induced a significantly greater bronchial reaction in patients with AA and bronchial hyperreactivity to histamine than in patients with AR and bronchial normoreactivity to histamine and controls. This difference was not found between subjects with AR and controls. 相似文献
993.
This paper describes a study of air concentrations of pollens and a calendar of pollination around the town of Split on the Croatian Adriatic in 1994. High pollen concentrations of Parietaria officinalis dominated during the year (up to 20% from April to June) followed by the pollens of Pistacia lentiscus, Olea europaea, Pinus halepensis, Juniperus oxycedrus, Acacia baileyana, Artemisia vulgaris, Ambrosia elatior and Cistus monspeliensis. In 1994-95, skin prick tests using commercially available standard inhalation allergens and specially prepared pollen allergens were performed on 3,500 patients with allergic respiratory symptoms. About 30% were allergic to standard pollen allergens (mixed grass pollen, mixed tree pollen, Parietaria officinalis and Pittosporum tobira). Hypersensitivity to more than one allergen was found in 45% of patients, whereas 15% did not react to any of the standard allergens. Additional testing with newly prepared individual allergens (P. lentiscus, O. europaea, P. halepensis, A. baileyana, C. monspeliensis, A. vulgaris, A. elatior) revealed hypersensitivity in a number of patients, but 36% showed no reaction. This finding suggests that further studies of this kind are needed for additional identification, isolation, and characterisation of pollen allergens that are present in the Adriatic coast. 相似文献
994.
Airborne fungi are sometimes associated with several respiratory diseases and allergies. This paper describes a study of qualitative and quantitative variations in the occurrence of airborne moulds in Zagreb area on three locations: centre of the city (C), Pharmaceutical Botanical Garden "Fran Kusan" (BG) and the mountain Medvednica (M) during autumn, winter, spring and summer 2002-03. Lower concentrations of airborne moulds were found in all three locations in autumn (up to 76.88 CFU/m3) and winter (31.46 CFU/m3), with significantly higher levels in C and BG than in M (P<0.001). In spring and summer, these concentrations were much higher in all sampling sites and were significantly higher in C (160.00 CFU/m3) and BG (134.00 CFU/m3) in spring than in M (90.07 CFU/m3) (P<0.001). In summer, significantly higher concentration was found in C (237.5 CFU/m3) than in BG (186.50 CFU/m3) (P<0.01), while concentrations in C and M (216.70 CFU/m3) were similar. Airspora belonging to 29 fungal genera were identified, and allergologicaly significant moulds, Cladosporium (up to 79.5%) and Alternaria (up to 59.4%) dominated in all sampling sites. Penicillium, Fusarium and Aspergillus were also constant fungal entities (43.0-70.5%), but in much lower concentrations than Cladosporium and Alternaria. Airsporas of Cladosporium and Alternaria were more frequent in spring and summer in all locations, with significantly higher concentrations in C and BG (P<0.05). The risk from allergies increases with higher airspora concentrations in spring and summer due to an increase in Cladosporium and Alternaria. 相似文献
995.
Although chemotherapy targets cancer tissue, it also damages the DNA of non-cancer cells. The aim of this study was to evaluate the in vitro genotoxic potential of therapeutic concentrations of bleomycin and mitomycin C, added alone or in combination to cultures of human peripheral lymphocytes. The levels of DNA damage and repair were assessed using the alkaline comet assay immediately after cell treatment as well as 24 and 48 hours following treatment. The results indicate that individual drugs and their combination induce a significant DNA damage to peripheral blood lymphocytes. Bleomycin alone induced the highest levels of primary DNA damage immediately after cell treatment. Although mitomycin C alone induced massive cross-linking and retarded DNA migration in resting cells, active proliferation and repair processes significantly increased DNA damage. Combined, they showed a synergetic effect, inducing complex patterns of DNA damage in peripheral blood lymphocytes and producing different types of lesions and a number of DNA alterations that directly or indirectly increased DNA migration. Our study has confirmed the sensitivity of the alkaline comet assay for assessing bleomycin and/or mitomycin C genotoxicity to human lymphocytes at concentration levels used in clinic. It has also demonstrated the utility of the alkaline comet assay as one of the primary screening methods for in vitro studies of drug-DNA interactions, especially in studying mechanisms of action of new drugs. 相似文献
996.
In this paper a room model with three modal distributions of attached radon progeny is developed. Recoil factors are recalculated for each of the modes, and different recoil factors than usually used are obtained. Dependence of progeny concentration in various modes on ventilation and attachment rate is presented. Unattached Pb is overestimated up to 15% if one modal distribution is used, which can lead to the overestimation of lung dose. 相似文献
997.
Results of systematic measurements of 90Sr activity concentrations in milk for the period 1961-2001 are summarized. An exponential decline of radioactivity followed the moratorium on atmospheric nuclear testing. The highest activity of 90Sr deposited by fallout, 1,060 Bq m(-2), was recorded in 1963, while the peak 90Sr activity concentration in milk, 1.42 +/- 0.17 Bq L(-1), was recorded in 1964. The values in year 2001 for fallout deposition and milk were 7.7 Bq m(-2) and 0.07 +/- 0.03 Bq L(-1), respectively. The reactor accident at Chernobyl caused higher 90Sr levels only in 1986. 90Sr fallout activity affects milk activity; the coefficient of correlation between 90Sr fallout activity and 90Sr activity concentrations in milk is 0.80. The transfer coefficient from fallout deposition to milk was estimated to be 2.5 x 10(-3) Bq y L(-1) per Bq m(-2). The dose incurred by milk consumption was estimated for the Croatian population, the annual collective effective dose in 2001 being approximately 2.0 person-Sv. 相似文献
998.
Parojcić J Ethurić Z Jovanović M Ibrić S Jovanović D 《The Journal of pharmacy and pharmacology》2004,56(6):735-741
The influence of dissolution media composition on drug release kinetics and in-vitro/in-vivo correlation (IVIVC) for hydrophilic matrix tablets based on Carbopol 971P and Carbopol 71G was investigated. A number of buffered and unbuffered media differing with respect to their pH value, ionic strength and ionic species was evaluated. The observed in-vitro drug release profiles were compared with the hypothetical drug release profiles in-vivo calculated by numerical deconvolution from the results of an in-vivo study. The obtained IVIVC plots were examined using linear and non-linear (proportional odds, proportional hazards and proportional reversed hazards) mathematical models. Although the studied sustained release agents were chemically identical, they exhibited pronounced differences in drug product behaviour both in-vitro and in-vivo. The use of non-linear modelling resulted in an improved level of correlation, especially in the case of Carbopol 71G matrices. The obtained results indicated the susceptibility of drug release kinetics and hence IVIVC in the case of anionic polymer matrices to media composition, and emphasized the need for thorough evaluation of applied media during the development of biorelevant dissolution methodology. Although the use of non-linear modelling could be advantageous, the need for a simple and meaningful non-linear relationship is pointed out. 相似文献
999.
Obradović D Tirard M Némethy Z Hirsch O Gronemeyer H Almeida OF 《Molecular pharmacology》2004,65(3):761-769
1000.
Mikov M Kevresan S Kuhajda K Jakovljević V Vasović V 《Polish journal of pharmacology》2004,56(3):367-371
The aim of the study was to test the efficacy of 3alpha,7alpha-dihydroxy-12-oxo-5beta-cholanate as a blood-brain barrier (BBB) permeator by examining its effect on quinine uptake into the central nervous system in rats, analgesic action of morphine, and on the sleeping time induced by pentobarbital. The obtained results indicate that sodium 3alpha,7alpha-dihydroxy-12-oxo-5beta-cholanate can be considered as modifier of BBB permeability, as it exhibited a promoting effect in all three tests. In the test of quinine uptake, methyl ester of 3alpha,7alpha-dihydroxy-12-oxo-5beta-cholanoic acid (included in the study for comparison) did not show a promoting effect, which can suggest its specific action. 相似文献