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31.
Dynamic motion of the pelvic floor muscles during voiding was analyzed using real‐time magnetic resonance imaging. To evaluate the contraction of the pelvic floor muscles, striated urethral sphincter distance, levator ani muscle thickness and anterior fibromuscular stroma distance were measured. The percent contraction of the striated urethral sphincter from before voiding to just before initiation of voiding was 14% in the normal group and 5% in the voiding dysfunction group. The percent contraction of the anterior fibromuscular stroma from before voiding to just before initiation of voiding was 11% in the normal group and 1% in the voiding dysfunction group; the percent contraction of the muscles was significantly greater in the normal group (P < 0.05). Striated urethral sphincter and anterior fibromuscular stroma contraction at initiation of voiding open the bladder neck and urethra. This plays an important role in the smooth initiation of voiding.  相似文献   
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Transdermal drug delivery is the way to transport drug carriers, such as nanoparticles, across the skin barrier to the dermal and/or subcutaneous layer. In order to control the transdermal drug delivery process, based on the heterogeneous and nonlinear structures of the skin tissues, we developed a novel electromechanical method combining in vivo local skin impedance probing, subcutaneous micro-injection of colloidal nanoparticles, and transcutaneous electrical stimulation. Experiments on the nude mice using in vivo fluorescence imaging exhibited significantly different apparent diffusion patterns of the nanoparticles depending on the skin impedance: Anisotropic and isotropic patterns were observed upon injection into low and high impedance points, respectively. This result implies that the physical complexity in living tissues may cause anisotropic diffusion of drug carriers, and can be used as a parameter for controlling drug delivery process. This method also can be combined with microneedle-based drug release systems, micro-fabricated needle-electrodes, and/or advanced in vivo targeting/imaging technologies using nanoparticles.  相似文献   
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Background: Endothelial cells (ECs) participate in key aspects of vascular biology, such as maintenance of capillary permeability, initiation of coagulation, and regulation of inflammation. According to previous reports, ECs have revealed highly specific characteristics depending on the organs and tissues. However, some reports have described the characteristics of the capillaries formed by human periodontal ECs. Therefore, the aim of the present study is to examine the functional characteristics of the periodontal microvascular ECs in vitro. Methods: Human periodontal ligament‐endothelial cells (HPDL‐ECs) and human gingiva‐endothelial cells (HG‐ECs) were isolated by immunoprecipitation with magnetic beads conjugated to a monoclonal anti‐CD31 antibody. The isolated HPDL‐ECs and HG‐ECs were characterized to definitively demonstrate that these cell cultures represented pure ECs. Human umbilical‐vein ECs and human dermal microvascular ECs were used for comparison. These cells were compared according to the proliferation potential, the formation of capillary‐like tubes, the transendothelial electric resistance (TEER), and the expression of tight junction proteins. Results: HPDL‐ECs and HG‐ECs with characteristic cobblestone monolayer morphology were obtained, as determined by light microscopy at confluence. Furthermore, the HPDL‐ECs and HG‐ECs expressed the EC markers platelet endothelial cell adhesion molecule‐1 (also known as CD31), von Willebrand factor, and Ulex europaeus agglutinin 1, and the cells stained strongly positive for CD31 and CD309. In addition, the HPDL‐ECs and HG‐ECs were observed to form capillary‐like tubes, and they demonstrated uptake of acetylated low‐density lipoprotein. Functional analyses of the HPDL‐ECs and HG‐ECs showed that, compared to the control cells, tube formation persisted for only a brief period of time, and TEER was substantially reduced at confluence. Furthermore, the cells exhibited delocalization of zonula occludens‐1 and occludin at cell–cell contact sites. Conclusions: The present results provide new evidence that HPDL‐ECs and HG‐ECs have characteristics of fenestrated capillaries. Therefore, capillaries in human periodontal tissues have functional characteristics of fenestrated capillaries, which might be related to the onset and the progression of systemic diseases and inflammation.  相似文献   
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Molecular‐targeted therapies directed against human epidermal growth factor receptor 2 (HER2) are evolving for various cancers. Neratinib is an irreversible pan‐HER tyrosine kinase inhibitor and has been approved by the FDA as an effective drug for HER2‐positive breast cancer. However, acquired resistance of various cancers to molecular‐targeted drugs is an issue of clinical concern, and emergence of resistance to neratinib is also considered inevitable. In this study, we established various types of neratinib‐resistant cell lines from HER2‐amplified breast and lung cancer cell lines using several drug exposure conditions. We analyzed the mechanisms of emergence of the resistance in these cell lines and explored effective strategies to overcome the resistance. Our results revealed that amplification of YES1, which is a member of the SRC family, was amplified in two neratinib‐resistant breast cancer cell lines and one lung cancer cell line. Knockdown of YES1 by siRNA and pharmacological inhibition of YES1 by dasatinib restored the sensitivity of the YES1‐amplified cell lines to neratinib in vitro. Combined treatment with dasatinib and neratinib inhibited tumor growth in vivo. This combination also induced downregulation of signaling molecules such as HER2, AKT and MAPK. Our current results indicate that YES1 plays an important role in the emergence of resistance to HER2‐targeted drugs, and that dasatinib enables such acquired resistance to neratinib to be overcome.  相似文献   
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目的:巨细胞病毒感染是器官移植后的一个严重并发症,回顾性分析肝移植术后患者巨细胞病毒感染的诊断和防治方法.方法:①回顾分析2005-05/2006-08解放军总医院第二附属医院全军器官移植中心收治的19例肝移植受者的临床资料,供者均为健康献肝者.供者、受者对治疗方案均知情同意,且得到医院伦理道德委员会批准.②术后1个月检测1次巨细胞病毒血清抗体,预防和治疗巨细胞病毒感染均采用静脉注射更昔洛韦.术后采用三联免疫抑制疗法,根据术后血药浓度及肝功能改变调整免疫抑制药物用量.③采用酶联免疫吸附法检测患者血中巨细胞病毒抗体巨细胞病毒IgG、巨细胞病毒IgM.结果:19例受者中6例发生巨细胞病毒感染,均无临床症状,并全部治愈.结论:更昔洛韦能够有效治疗肝移植术后巨细胞病毒感染.积极预防、早期治疗肝移植术后患者巨细胞病毒感染是治疗成功的关键.  相似文献   
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4生物学和医学意义 4.1循环功能:具有循环功能的形态学依据是经苏木精和伊红(H&E)染色"[73]和多种类型的屯子显微镜如透射电子显微镜、高压透射电子显微镜、蚀刻电子显微镜和聚焦离子束扫描式电子显微镜[43-45]确认的BH管的管道.细胞水平的研究发现,组成BH管的管道内壁的内皮细胞,可用透射电子显微镜确定"[73].一项免疫组化方面的研究可证明内皮细胞的存在[52].  相似文献   
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A new technique for visualizing Bonghan ducts (BHDs) and Bonghan corpuscles (BHCs) was developed by using a vivi-staining dye, Trypan blue. The dye stains BHDs and BHCs preferentially to adipocytes so that tracking a BHD and a BHC, even inside adipose tissues, is possible. Concerning the functions of the BHD and the BHC in adipose tissues, we propose conjectures: the Bonghan system may be niches for mesenchymal stem cells, which can differentiate into adipocytes, and pathways for macrophages involved in adipogenesis.  相似文献   
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