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161.
The aim of this study was to determine whether corticotropin-releasing hormone (CRH) regulates human trophoblast cell growth. The results showed that exogenous CRH significantly stimulated human trophoblast proliferation in first-trimester primary cultures. In vivo, CRH was strongly immunolocalised to cytotrophoblastic cells in proliferative cell columns and in chorionic villi. We postulate that CRH may have an important role in early placental development and successful pregnancy.  相似文献   
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The use of end-to-side neurrorhaphy remains a controversial topic in peripheral nerve surgery. The authors report the long-term functional outcome following a modified end-to-side motor reinnervation using the spinal accessory to innervate the suprascapular nerve following a C5 to C6 avulsion injury. Additionally, functional outcomes of an end-to-end neurotization of the triceps branch to the axillary nerve and double fascicular transfer of the ulnar and medial nerve to the biceps and brachialis are presented. Excellent functional recoveries are found in respect to shoulder abduction and flexion and elbow flexion.  相似文献   
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目的 探讨不同组织类型胃癌局部免疫细胞及细胞因子表达的特性。方法 采用高敏感放射性标记半定量逆转录 聚合酶链反应 (RT PCR)技术检测胃癌患者癌组织及非癌性黏膜组织中不同T细胞亚群 2 4个亚家族的T细胞受体 β链可变区表达以及T细胞亚群、上皮细胞的细胞因子表达谱。结果 弥散型胃癌组织CD8+ T细胞亚群中增殖性T细胞克隆数目明显低于肠型胃癌 (P =0 0 46 )。弥散型胃癌中 ,癌组织CD8+ T细胞中白细胞介素 (IL) 6、IL 8、CD4+ T细胞中肿瘤坏死因子(TNF) αmRNA的水平 (0 6 1± 0 2 9,0 5 6± 0 2 2 ,0 0 9± 0 0 3)较非癌性黏膜组织中的 (0 14± 0 0 5 ,0 2 7± 0 0 9,0 0 4± 0 0 2 )增高 (P =0 0 2 8,P =0 0 43,P =0 0 46 ) ;而肠型胃癌中 ,癌组织CD8+ T细胞及上皮细胞中IL 8mRNA的水平 (0 5 7± 0 2 5 ,0 2 7± 0 0 7)较非癌性黏膜组织中的 (0 2 1± 0 0 7,0 14± 0 0 6 )增高 (P =0 0 2 8,P =0 0 2 8)。结论 不同组织类型胃癌局部免疫细胞及细胞因子表达的特性不同 ,弥散型胃癌中增殖性T细胞克隆少、局部多种免疫抑制型细胞因子的高表达提示 :弥散型胃癌肿瘤局部的免疫抑制比肠型胃癌更严重。  相似文献   
166.
The cytologic diagnosis of primary conventional renal-cell adenocarcinoma (cRCC) is usually straightforward; however, metastatic cRCC must be distinguished from a variety of neoplasms with clear-cell features. CD10, a cell membrane-associated neutral endopeptidase, and renal-cell carcinoma marker (RCCma), an antibody against human proximal tubular brush border antigen, have recently been shown to be useful in the diagnosis of cRCC. We compared CD10 and RCCma in cell block material from fine-needle aspiration biopsies (FNABs) to assess their utility in the diagnosis of metastatic cRCC, in cytologic specimens. Seven primary and sixteen metastatic cRCCs were immunostained with CD10 and RCCma. The immunoreactivity results were compared with those of a variety of neoplasms originating from other sites such as the liver, lungs, breast, and the gastrointestinal tract. The sensitivity and specificity of CD10 for cRCC were 100% and 59%, respectively. The sensitivity and specificity of RCCma for cRCC were 35% and 100%, respectively. We conclude that CD10 has limited value in confirming the diagnosis of cRCC because of its low specificity. RCCma, when positive, is highly specific for cRCC, but its low sensitivity hinders its diagnostic usefulness.  相似文献   
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168.
Yim EK  Reano RM  Pang SW  Yee AF  Chen CS  Leong KW 《Biomaterials》2005,26(26):5405-5413
Cells are known to be surrounded by nanoscale topography in their natural extracellular environment. The cell behavior, including morphology, proliferation, and motility of bovine pulmonary artery smooth muscle cells (SMC) were studied on poly(methyl methacrylate) (PMMA) and poly(dimethylsiloxane) (PDMS) surfaces comprising nanopatterned gratings with 350 nm linewidth, 700 nm pitch, and 350 nm depth. More than 90% of the cells aligned to the gratings, and were significantly elongated compared to the SMC cultured on non-patterned surfaces. The nuclei were also elongated and aligned. Proliferation of the cells was significantly reduced on the nanopatterned surfaces. The polarization of microtubule organizing centers (MTOC), which are associated with cell migration, of SMC cultured on nanopatterned surfaces showed a preference towards the axis of cell alignment in an in vitro wound healing assay. In contrast, the MTOC of SMC on non-patterned surfaces preferentially polarized towards the wound edge. It is proposed that this nanoimprinting technology will provide a valuable platform for studies in cell-substrate interactions and for development of medical devices with nanoscale features.  相似文献   
169.
The ATR-dependent DNA damage response pathway can respond to a diverse group of lesions as well as inhibitors of DNA replication. Using the Xenopus egg extract system, we show that lesions induced by UV irradiation and cis-platinum cause the functional uncoupling of MCM helicase and DNA polymerase activities, an event previously shown for aphidicolin. Inhibition of uncoupling during elongation with inhibitors of MCM7 or Cdc45, a putative helicase cofactor, results in abrogation of Chk1 phosphorylation, indicating that uncoupling is necessary for activation of the checkpoint. However, uncoupling is not sufficient for checkpoint activation, and DNA synthesis by Polalpha is also required. Finally, using plasmids of varying size, we demonstrate that all of the unwound DNA generated at a stalled replication fork can contribute to the level of Chk1 phosphorylation, suggesting that uncoupling amplifies checkpoint signaling at each individual replication fork. Taken together, these observations indicate that functional uncoupling of MCM helicase and DNA polymerase activities occurs in response to multiple forms of DNA damage and that there is a general mechanism for generation of the checkpoint-activating signal following DNA damage.  相似文献   
170.
To characterize the phenotypes and genotypes of erythromycin-resistant clinical isolates of Streptococcus pneumoniae in Korea and to evaluate the in vitro activity of telithromycin against these erythromycin-resistant isolates, we tested a total of 676 isolates of S. pneumoniae collected from 1997 to 2002 in a tertiary hospital in Seoul, Republic of Korea. MICs for erythromycin and telithromycin were determined by the agar dilution method. The macrolide resistance phenotypes of erythromycin-resistant isolates were determined by the erythromycin- clindamycin-rokitamycin triple disk (ECRTD) and MIC induction tests, whereas their macrolide resistance genotypes were determined by PCR for the erm(B), erm(A), subclass erm(TR), and mef genes. To discriminate between mef(A) and mef(E), PCR-restriction fragment length polymorphism (RFLP) analyses were performed. Of the 676 S. pneumoniae isolates, 459 (67.9%) were resistant to erythromycin. Of the 459 erythromycin-resistant isolates, 343 (74.7%) were assigned to the cMLS phenotype, 48 (10.4%) to the iMcLS phenotype, 4 (0.9%) to the iMLS phenotype, and 64 (14.0%) to the M phenotype. The erm(B) gene was detected in 251 (54.6%) isolates, the mef gene was detected in 64 (14.0%), and both the erm(B) and mef genes were detected in 144 (31.4%) isolates. All of the mef genes detected were identified as mef(E). Of the 459 erythromycin- resistant isolates, all but one were susceptible to telithromycin. The MIC(50)/MIC(90) to telithromycin of isolates carrying erm(B), mef(E), and both genes was 0.06/0.5 microg/ml, 0.03/0.125 microg/ml, and 0.5/1.0 microg/ml, respectively. Although the MICs of telithromycin for the erythromycin-resistant isolates varied according to genotype, telithromycin was very active against these erythromycin-resistant S. pneumoniae.  相似文献   
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