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61.
Morphological analysis of the cervical spinal canal,dural tube and spinal cord in normal individuals using CT myelography 总被引:3,自引:0,他引:3
To verify the conventional concept of developmental stenosis of the cervical spinal canal, we performed a morphological analysis of the relations of the cervical spinal canal, dural tube and spinal cord in normal individuals. The sagittal diameter, area and circularity of the three structures, and the dispersion of each parameter, were examined on axial sections of CT myelograms of 36 normal subjects. The spinal canal was narrowest at C4, followed by C5, while the spinal cord was largest at C4/5. The area and circularity of the cervical spinal cord were not significantly correlated with any parameter of the spinal canal nor with the sagittal diameter and area of the dural tube at any level examined, and the spinal cord showed less individual variation than the bony canal. Compression of the spinal cord might be expected whenever the sagittal diameter of the spinal canal is below the lower limit of normal, that is about 12 mm on plain radiographs. Thus, we concluded that the concept of developmental stenosis of the cervical spinal canal was reasonable and acceptable. 相似文献
62.
Adam Greenspan M.D. 《Skeletal radiology》1991,20(8):561-583
Sclerosing bone dysplasias are a poorly understood group of developmental anomalies, much of whose etiology is still obscure. The list of conditions constituting this group is relatively short: osteopetrosis (Albers-Schönberg disease), pycnodysostosis (Maroteaux-Lamy disease), enostosis (bone island), osteopoikilosis, osteopathia striata (Voorhoeve disease), progressive diaphyseal dysplasia (Camurati-Engelmann disease), hereditary multiple diaphyseal sclerosis (Ribbing disease), four types of endosteal hyperostosis (van Buchem disease, Worth disease, Nakamura disease, and Truswell-Hansen disease), dysosteosclerosis, metaphyseal dysplasia (Pyle's disease), craniometaphyseal dysplasia, melorheostosis (Leri disease), and craniodiaphyseal dysplasia. There are instances in which two or more of the above disorders coexist. These are termed overlap syndromes, most commonly involving osteopathia striata, osteopoikilosis, and melorheostosis. A classification of these dysplasias is elaborated based on a target-site approach that views them as disturbances in development associated with the processes of either endochondral or intramembranous bone formation, or both. Accumulated evidence suggests that many of these disorders stem from common defects in bone resorption and/or formation during the processes of skeletal maturation and modeling. Finally, the subgroup of overlap syndromes is emphasized as indicating a strong interrelationship between the sclerosing dysplasias of bone, with perhaps a common pathogenesis for many.This article is one in a series of review articles which represent expansions of papers presented at the annual meeting of the International Skeletal Society and were solicited by the editors 相似文献
63.
Based on lateral hypothalamic self-stimulation behavior of the rat in a Skinner box, a "conflict" situation was established by combining foot shock punishment with brain stimulation. Diazepam (10-20 mg/kg, PO) caused a marked increase in the lever pressing response in the punished period without affecting the unpunished response. Bromazepam (10--20 mg/kg PO) also caused an increase in the lever pressing response in the punished period and a decrease of the punished response. These results indicate that a "conflict" situation based on self-stimulation behavior is useful for the evaluation of antianxiety action. 相似文献
64.
头孢类抗生素国内市场状况 总被引:3,自引:0,他引:3
目的为国内制药企业及相关科研单位的品种开发提供参考。方法根据所查阅的文献综述了近年来国内头孢类抗生素品种的发展状况、生产厂家、产量及医院用药情况。结果与结论提供了国内头孢类抗生素的开发品种及最新进展 相似文献
65.
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67.
R. Bunikowski I. Grimmer A. Heiser B. Metze A. Schäfer M. Obladen 《European journal of pediatrics》1998,157(9):724-730
To study the developmental effects of prenatal exposure to opiates, a prospective follow up study of 34 drug-exposed (opiates
and nicotine) and 42 reference infants (nicotine exposure only) was conducted from January 1992 to September 1995. At the
time of delivery, 12 of 34 mothers used opiates without medical control. Twenty-two mothers participated in a methadone maintenance
programme. At 1 year, the average Griffiths Developmental Quotient (DQ) was lower in the drug-exposed group (mean: 100.5 vs.
references 107.9; P < 0.001). This difference was mainly due to lower subscales “locomotor” (mean 100.8 vs. 111.4; P < 0.05) and “intellectual performance” (mean 100.8 vs. 108.5; P < 0.05) in the drug-exposed group. Severe developmental retardation mean DQ (−2 SD) was diagnosed in 2 drug-exposed infants.
Mild developmental retardation (mean DQ: 1 SD– > 2 SD) was found in 7 drug-exposed and in 3 reference infants (P < 0.05). Neurological abnormalities were found more frequently in the drug-exposed group (11 vs. 3 infants; P < 0.01). Among the opiate-exposed infants, the subscales “hearing and speech” and “intellectual performance” were lower in
the uncontrolled drug-using than in the methadone group. The 17 fostered infants showed no difference in developmental outcome
compared with the 10 infants living with their biological parents (mean DQ: 100.0 versus 101.3).
Conclusions At 1 year infants prenatally exposed to opiates are at risk for mild psychomotor developmental impairment.
Received: 1 August 1997 / Accepted in revised form: 15 January 1998 相似文献
68.
五氧化二钒对大鼠胚胎中脑细胞增殖和分化的影响 总被引:2,自引:1,他引:2
本研究采用微团培养观察了V2O5对大鼠胚胎中脑细胞增殖和分化的影响,旨在为进一步揭示其发育毒作用机理提供依据。结果显示,V2O5对体外中脑细胞的增殖和分化均有抑制作用,并有明显的剂量-反应关系。V2O5抑制中脑增殖经的I C50分别为9.1和6.8μmol/L。体内/体外结合试验显示,V2O5在2.0mg/kg时对细胞分化有明显的抑制作用,而在5.0mg/kg时才对细胞增殖出现抑制作用,按照Ren 相似文献
69.
70.
壬基酚对小鼠生育力的影响研究 总被引:3,自引:1,他引:3
目的 研究壬基酚(NP)经口染毒对昆明种小鼠生育力的影响,并评价其生殖和发育毒性.方法 选择健康性成熟的清洁级的昆明种小鼠128只,体重22~26 g,随机分为24、60、120 mg/kg NP染毒组和1个花生油溶剂对照组,每组32只,雌雄各半.进行小鼠生育力试验.结果 从60 mg/kg组开始,精子计数、活精率、生育指数、妊娠率均随染毒剂量增加而下降,精子畸形率随剂量增加而升高(P<0.05或P<0.01);交配指数仅在120mg/kg组下降(P<0.05);从24mg/kg组开始,平均每窝黄体数、着床数、活胎数均随染毒剂量升高而下降,存在明显的剂量-效应关系(P<0.05或P<0.01);而着床前死亡率、吸收胎率、死胎率均随染毒剂量增加而升高(P<0.05或P<0.01).结论 经口染毒壬基酚对小鼠产生明显的生殖和发育毒性. 相似文献