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81.
无创性动态血压(ABPM)能较客观地反映血压水平及其昼夜变化规律,对高血压病的诊断、指导用药、药物疗效的评定以及预后评估等均有较大价值。本文对ABPM的发展及临床应用等问题进行综述。 相似文献
82.
目的:通过膝关节损伤MRI影像的分析,确定其诊断价值及意义。材料和方法:本文收集了自1992年以来我院所检查的42例膝关节损伤患者,52个膝关节成像。其中男性34人;女性8人,各年龄组以30~40岁组最多。损伤以前交叉韧带和外侧半月板损伤者多见,分别占总损伤数的20%及30%。损伤又以左膝多见,占总数的61%。结果:MRI能较明确地显示膝关节的半月板、关节软骨、韧带、滑膜及骨质的改变,明显地比CT所能看到的层次多,对软组织的损伤显示清晰。结论:只要正确地应用不同序列及切层方向、厚度等技术,可清晰地显示其信号特征,从而能确定其损伤部位、程度。 相似文献
83.
84.
H. W. Chu S. Balzar J. Y. Westcott J. B. Trudeau Y. Sun D. J. Conrad S. E. Wenzel 《Clinical and experimental allergy》2002,32(11):1558-1565
BACKGROUND: Although 15(S)-hydroxyeicosatetraenoic acid (15(S)-HETE), a product of 15-lipoxygenase (15-LO), may be involved in mild to moderate asthma, little is known about its potential roles in severe asthma. OBJECTIVES: This study was performed to evaluate 15(S)-HETE levels in bronchoalveolar lavage fluid (BALF) from severe asthmatics with and without airway eosinophils and from the control groups. In addition, 15-LO protein expression was examined in endobronchial biopsy, while its expression and activation were evaluated in BAL cells. RESULTS: While 15(S)-HETE levels in BALF were significantly higher in all severe asthmatics than normal subjects, severe asthmatics with airway eosinophils had the highest levels compared with mild, moderate asthmatics and normal subjects. 15(S)-HETE levels were associated with tissue eosinophil numbers, sub-basement membrane thickness and BALF tissue inhibitor of metalloproteinase-1 levels, and were accompanied by increased 15-LO expression in bronchial epithelium. In addition, activation of 15-LO was suggested by the increased proportion of 15-LO in the cytoplasmic membrane of alveolar macrophages from severe asthmatics. CONCLUSION: The data suggest that severe asthmatics with persistent airway eosinophils manifest high levels of 15(S)-HETE in BALF, which may be associated with airway fibrosis. It is likely that 15-LO expression and activation by airway cells explain the increased 15(S)-HETE levels. 相似文献
85.
86.
保留盆腔自主神经的全直肠系膜切除的临床应用及评价 总被引:4,自引:0,他引:4
目的探讨保留盆腔自主神经(PANP)的全直肠系膜切除(TME)在男性直肠癌低位保肛术中的应用。方法回顾性分析传统手术、TME和PANP+TME在男性直肠癌保肛手术中的应用,对各组病人肿瘤下缘距肛门距离、3年存活率、局部复发率、排尿功能、性功能作一评价。结果TME组和PANP+TME组手术病人的肿瘤下缘距肛门距离较传统手术组明显缩短(P〈0.05);3组的3年存活率分析差异无显著性(P〉0.05);TME组和PANP+TME组的局部复发率较传统手术组明显降低(P〈0.05);传统手术组、TME组、PANP+TME组的排尿障碍、勃起功能障碍和射精功能障碍的发生率逐渐降低,3组间两两比较差异均有显著性(P〈0.05)。PANP手术分型与排尿障碍、勃起功能障碍和射精功能障碍分级呈正相关(P〈0.05)。结论TME可以降低直肠癌的局部复发率,降低排尿障碍和性功能障碍的发生率;PANP和TME结合使排尿障碍和性功能障碍的发生率更加降低,PANP手术保留神经越彻底,手术后排尿障碍、性功能障碍的发生率越低。 相似文献
87.
C E Chu A Cooke J B Stephenson J L Tolmie B Clarke W L Parry-Jones J M Connor M D Donaldson 《Archives of disease in childhood》1994,71(5):441-442
Thirty one patients with the putative diagnosis of Prader-Willi syndrome were reassessed clinically and by DNA analysis. Eleven patients were judged not to have Prader-Willi syndrome and 20 to have the condition. This was confirmed by DNA analysis in all but one case. The diagnosis of Prader-Willi syndrome, especially in early infancy, should be made with caution unless confirmed by molecular genetic studies. 相似文献
88.
89.
There is a great deal of indirect, nonexperimental evidence that a pattern of earlier-stage disease at diagnosis has a better outcome. Increased early detection activities can change, these stage patterns while various biases and the question of generalizability need to be kept in mind in their interpretation. The indirect evidences of possible benefit from early detection activities includes an increase in the number of cases detected, a pattern of more early- and less advanced-stage cases, an increase in the overall site-specific survival rate, and a decrease in the case fatality rate. Unless these intermediate markers are favorable, it is unlikely that early detection will reduce mortality. In addition, one should also differentiate a reduced incidence or a change in treatment as a cause for reduced mortality. 相似文献
90.
The role of various subfamilies of rat hepatic cytochrome P450 in the oxidation of ethosuximide was evaluated by comparing ethosuximide clearance in control rats and those pretreated with relatively selective P450 inducers and/or inhibitors. Clotrimazole pretreatment increased ethosuximide clearance threefold (p less than 0.005). Dexamethasone increased ethosuximide clearance twofold (p less than 0.001), and the dexamethasone effect was completely abolished by a single dose of triacetyloleandomycin. These results suggest a prominent role for cytochrome P450IIIA in ethosuximide metabolism in the rat. Isoniazid increased ethosuximide clearance twofold (p less than 0.001), and this effect was abolished by a single dose of diallylsulfide, suggesting that ethosuximide is also processed by cytochrome P450IIE1 in rats. Phenobarbital pretreatment increased ethosuximide clearance 2-2.7 fold (p less than 0.001); an effect that was only partially reversed by orphenadrine, an inhibitor of cytochrome P450IIB/IIC enzymes. This suggests a quantitatively less important role for the IIB/IIC subfamilies in processing ethosuximide, since phenobarbital is an inducer of P450 subfamilies IIB, IIC, IIE, and IIIA. Neither the cytochrome P450IA inducer, beta-naphthoflavone, nor the inhibitor, alpha-naphthoflavone altered ethosuximide clearance. Ajmaline, an inhibitor of cytochrome P450IID, had no effect on ethosuximide clearance. Together, these findings suggest that ethosuximide is principally oxidized by cytochrome P450IIIA, and that cytochrome P450IIE may play an important role. Cytochromes P450IIB/C play less prominent roles in ethosuximide oxidation, and neither cytochrome P450IA nor cytochrome P450IID is involved. 相似文献