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991.
Methanol extracts of the root of Dipsacus asper Wall (Dipsacaceae) were found to exhibit apoptosis-inducing activities in U937 (human monocyte-like histiocytic) cells. Investigation of the active n-BuOH fraction led to the isolation of akebia saponin D (ASD). Structure was established by spectroscopic methods. Treatment of U937 cells with ASD induced apoptosis in a dose dependent manner. ASD exerted strong cytotoxicity against human and murine leukemia cells. It is significantly increased the subG1 cell population and expression of p53 and Bax gene. And also ASD enhanced NO production from RAW264.7 macrophage cells. Taken together, these results strongly indicate that ASD may exert apoptosis-inducing activity via induction of apoptosis through activation chiefly via the nitric oxide and apoptosis-related p53 and Bax gene expression. These data provide scientific evidence that Dipsacus asper Wall can be useful as a chemopreventive agent.  相似文献   
992.
Endoglin (CD105) is an accessory protein of the transforming growth factor-beta receptor system expressed on vascular endothelial cells. Mutation of the endoglin gene is associated with hereditary hemorrhagic telangiectasias, or Osler-Weber-Rendu syndrome, and has been studied extensively in the context of this disease. The expression of endoglin is elevated on the endothelial cells of healing wounds, developing embryos, inflammatory tissues, and solid tumors. Endoglin is a marker of activated endothelium, and its vascular expression is limited to proliferating cells. Recent studies identified endoglin expression in several solid tumor types, with the level of expression correlating with various clinicopathologic factors including decreased survival and presence of metastases. Attempts to target endoglin and the cells that express this protein in tumor-bearing mice have yielded promising results.  相似文献   
993.
缺血性脑卒中患者阿司匹林抵抗现象及处理策略   总被引:1,自引:0,他引:1  
阿司匹林作为缺血性脑血管病的一级和二级预防用药,广受关注。然而长期服用阿司匹林的患者仍会发生动脉血栓形成事件,因此本文就阿司匹林抵抗的概念、发生机制、检测方法、预防措施及其在缺血性脑血管病中的临床意义加以综述。  相似文献   
994.
王晓青 《中国医药导报》2007,4(12S):102-103,165
目的:探讨音乐疗法在围手术期护理中的作用。方法:选择在我院实施局麻手术患者120例,随机分为观察组和对照组,两组均进行常规护理,观察组同时在术前、术中、术后收听自己喜欢的音乐。对两组焦虑水平、术中麻醉药用量和术后疼痛程度进行比较。结果:观察组术前SAS评分和焦虑发生率均明显低于对照组(P〈0.05),而术后两组无显著性差异(P〉0.05);观察组术中咪唑安定使用量明显少于对照组(P〈0.05),利多卡因使用量也少于对照组,但无显著性差异(P〉0.05);观察组术后疼痛分级明显低于对照组(P〈0.01)。结论:在同手术期护理中应用音乐疗法,可以减轻患者焦虑、减少麻醉药用量,缓解疼痛,促进康复。  相似文献   
995.
Freezing immature oocytes   总被引:3,自引:0,他引:3  
The establishment of a long-term preservation system for mammalian oocytes is important for the development of both biological and medical sciences. A number of efforts have been made to develop this system. In human reproductive medicine, the development of an oocyte cryopreservation system can improve the efficacy of the current assisted reproductive technology (ART) for infertile patients with severe reproductive disorders. In this article, the technical development of cryopreservation programs for human oocytes and its biological background were reviewed. Clinical outcome after the use of this technology was further introduced.  相似文献   
996.
The metabolisms of tamoxifen in female rat, mouse and humanliver microsomal preparations were compared. Rat, mouse andhuman liver microsomes were incubated with tamoxifen in thepresence of NADPH and MgCl2 and the metabolites formed wereanalysed by on-line HPLC electrospray ionization MS. The majormetabolites formed by rat liver microsomes were 4-hydroxytamoxifen,4'-hydroxytamoxifen, N-desmethyltamoxifen and tamoxifen N-oxide.In addition, two epoxide metabolites, 3,4-epoxytamoxifen and3',4'-epoxytamoxifen, and their hydrolysed derivatives, 3,4-dihydrodihydroxytamoxifenand 3',4'-dihydrodihydroxytamoxifen, have been identified. Thepattern of the main metabolites obtained with human liver microsomesresembles qualitatively that of rat liver microsomes. The majordifferences between rat and human liver microsomes were thatthe amount of hydroxylated metabolites were much lower in humanand only traces of 3,4-epoxytamoxifen and the correspondingdihydrodihydroxy derivative were detected. No 3',4'-epoxytamoxifendetected in human liver microsomes. The four major metaboliteswere also formed in much larger amounts and with faster ratesof formation by mouse liver microsomes, though tamoxifen N-oxideclearly predominated in this species. Polar metabolites, 3,4-dihydroxytamoxifenand 4-hydroxytamoxifen N-oxide, which were undetectable in ratand human, were formed in significant amounts in mouse microsomes.As in human microsomes, there was only one epoxide metabolite,3,4-epoxytamoxifen, produced by mouse liver microsomes at levelslower than that found in rat. The faster rate of metabolismand the production of polar metabolites may indicate the abilityof mouse to detoxify tamoxifen by rapid elimination comparedwith rat and human. The production of a larger amount of potentiallyreactive epoxide metabolites in rat may be responsible for theliver carcinogenesis in this species.  相似文献   
997.
Sialoglycoconjugates in the developing murine tubotympanum were characterized using lectin histochemistry with wheat germ agglutinin (WGA), Limax flavus agglutinin (LFA), Sambucus nigra agglutinin (SNA), Maackia amurensis agglutinin (MAA), peanut agglutinin (PNA), and neuraminidase treatment. WGA, LFA, MAA, and neuraminidase-PNA labeled epithelial goblet cells, glandular mucous cells, and cell surfaces of adult and newborn murine tubotympanum. SNA did not label any secretory components. PNA labeled secretory cells and cell surfaces of the fetal tubotympanum without neuraminidase treatment. After birth, these secretory cells and cell surfaces were labeled with PNA only after neuraminidase treatment. These results revealed that: Sialoglycoconjugates are produced from glandular mucous cells and epithelial goblet cells and are present on cell surfaces and within the mucous blanket; their terminal tri-saccharide linkage appears to be the sequence Neu5Ac(alpha 2-3)Gal(beta 1-3)GalNAc; sialic acids appear before birth and gradually increase; terminal galactose residues are masked by sialic acids after birth.  相似文献   
998.
We present 4 neonates with enteroviral meningitis. The cerebrospinal fluid findings were variable and posed a diagnostic problem. Immediate outcome was excellent and 3 of the 4 infants were normal at follow-up at 6 months of age. However long-term follow-up will be necessary to to determine any long-term sequelae.  相似文献   
999.
Aplasia cutis congenita (ACC) including epidermolysis bullosa (EB) are rare congenital conditions. In ACC there is a localised absence of skin while in EB blistering occurs with a split at the epidermal or dermal level. In the past these 2 conditions have been reported to occur in the same patient. A case of a Gurkha baby girl illustrating just such an entity with severe erosive defects over the head, face, trunk and acral parts of the limbs presenting at birth is reported. There was also widespread blistering over the chest, abdomen and back. The baby died after 3 days from serious complications.  相似文献   
1000.
Summary Microprobe analysis was performed at the cellular and subcellular levels of type I and type II vestibular hair cells. In principle the same types of elemental histograms were found in the two types of hair cells studied. High concentrations of Cl and K were detected in stereocilia, whereas calcium was found when analyzing stereocilia and the supranuclear cytoplasm.Supported by grants from the Swedish Medical Research Council (12X-720 and 12X-7305), the Swedish Society for Medical Sciences, the Foundation Tysta Skolan, and the Ragnar and Torsten Söderberg Foundation  相似文献   
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