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101.
1临床资料2002-01/2004-02收治临床症状典型且无并发症毛细支气管炎患儿116例,发病年龄3-24(平均8.4)mo,男61例,女55例,按就诊时间顺序分为氨溴索雾化吸入组(观察组)、氨溴索静脉点滴组(对照Ⅰ组)和常规治疗组(对照Ⅱ组),分别为38,39,39例.常规治疗组给予头孢噻肟钠50mg/kg,2/d及穿琥宁80-120mg/d分别静脉滴注及对症治疗(如吸氧、镇静、退热等处理);观察组在常规治疗的基础上加用氨溴索4mg加生理盐水10mL超声雾化吸入10~15min,2/d; 相似文献
102.
Differential induction of chemokines in human microglia by type I and II interferons 总被引:1,自引:0,他引:1
Chemokines are secreted proteins that function as chemoattractants, mediating the recruitment of specific subsets of leukocytes to sites of tissue damage and immunological reactions. Chemokines may also function as antiviral agents, since viruses such as human immunodeficiency virus type 1 (HIV-1) use chemokine receptors as co-receptors for viral entry. This study examines whether virus-induced interferon, IFNbeta, or immune-related interferon, IFNgamma, affects the production of beta-chemokines by CNS microglia and peripheral monocytes. When IFNbeta was used as the stimulus, induction of MIP-1alpha, MIP-1beta, MCP-1, and RANTES mRNA and protein was observed within 12 h of stimulation in microglia. By contrast, when IFNgamma was used as the stimulus, only MCP-1 was induced. IFNbeta stimulation of blood monocytes resulted in upregulation of MIP-1alpha, MIP-1beta, and MCP-1. Thus, type I and II interferons differentially regulate beta-chemokines in human fetal microglia and peripheral blood monocytes. These observations may have relevance for the therapeutic activity of IFNbeta in multiple sclerosis and for the antiviral effects of IFNbeta for HIV-1 infection of monocytes and microglia. 相似文献
103.
J John LJ Björklund NW Svenningsen B Jonson 《Acta paediatrica (Oslo, Norway : 1992)》1994,83(9):903-909
Failure of neonatal patient triggered ventilation may reflect a delay in delivery of flow relative to the inspiratory effort of the infant. Transmission of diaphragmatic contraction to the sensor site (patient delay) and further transmission to and within the sensing device (device delay) both contribute to the delay in triggering. Patient and device delays were studied for different sensing systems in 36 infants, 24 of whom were intubated. Device delay was long (<40 ms) with a conventional apnoea monitor compared with sensors placed at the airway opening (2 ms), the inspiratory (12 ms) and expiratory (3 ms) pressure transducers of the ventilator, the Graseby capsule (8 ms), strain gauges (3 ms) and oesophageal pressure (6 ms). In near normal infants, the sum of patient and device delays for the latter sensors was less than 20 ms and a minor component of the total delay. However, in severe lung disease the total delay may be more than 100ms even for airway sensors. 相似文献
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Conotoxin GI, a peptide neurotoxin contained in the venom of the marine snail Conus geographus, was applied to the cutaneous pectoris muscle of the frog, and the effects on the postsynaptic response to acetylcholine were examined. Conotoxin GI reversibly blocked nerve-evoked muscle contractions at concentrations greater than or equal to 3 to 4 microM. Micromolar concentrations of conotoxin GI significantly reduced the amplitude of miniature endplate potentials and membrane depolarizations produced by ionophoretic application of acetylcholine, suggesting that the toxin reduced the postsynaptic sensitivity to acetylcholine. The reduction in the sensitivity of the muscle to acetylcholine was not due to changes in muscle fiber resting membrane potential or input resistance. Conotoxin GI reduced the amplitudes but did not affect the rates of decay of focal, extracellularly recorded endplate currents or miniature endplate currents, suggesting that the toxin did not affect the lifetime of ion channels opened by acetylcholine. Miniature endplate currents decay five to six times more slowly than normal when acetylcholinesterase is blocked with neostigmine methyl sulfate due to repeated binding of acetylcholine to receptors as it diffuses from the synaptic cleft. Conotoxin GI reduced the amplitude and increased the rate of decay of miniature endplate currents recorded in the presence of neostigmine methyl sulfate, suggesting that the toxin reduced the binding of acetylcholine to endplate receptors. These results are consistent with the hypothesis that conotoxin GI blocks neuromuscular transmission at the frog endplate by reducing the binding of acetylcholine to receptors. 相似文献
107.
Dr. Yvonne Brackbill PhD Lynn Woodward BA MS Karen A. McManus BA MS Michael J. Ireson PhD 《Journal of Midwifery & Women's Health》1984,29(3):177-185
This study sought to identify some important characteristics of women who reject hospitals as a place of birth and to determine whether those characteristics are also associated with choice between the two nontraditional alternatives available, ie, birth in a free-standing birth center and birth at home. Data were obtained from 200 mothers on demographics and health-promoting behaviors, with particular focus on exposure to and information about drugs during pregnancy and childbirth, perceived locus of control, factors entering into the decision to choose one or the other nontraditional birthplaces, and extent of satisfaction with this choice. There were differences between groups in the use of drugs for health-related complaints, in information about drugs, and in consumption of drugs (including drugs implicated as teratogenic) during pregnancy and childbirth. There were no differences in the extent to which mothers perceived themselves as being in control of their environments or in the extent to which they engaged in behavior known to promote health and prevent disease. 相似文献
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Tubule-like cells were found lining an artery and several arterioles and within the capillaries of infarcted glomeruli in one block of kidney from one of 54 cases of end-stage/dialysis kidneys. Three other blocks showed tubule-like structures within infarcted glomeruli and adjacent arterioles. Squamous metaplasia of remaining tubule epithelium was found in sections from four blocks of the same kidney. In two of these blocks, infarcted glomeruli had capillaries which were occupied by squamous cells. These findings are discussed as examples of metaplasia of the endothelium or alternatively as epithelial growth and invasion. The use of special stains and multiple blocks for this study seem to have been justified. These changes offer further evidence that the end-stage kidney after dialysis has unique alterations. 相似文献
110.