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101.
顺铂引起卵巢癌细胞周期变化及凋亡的观察 总被引:1,自引:0,他引:1
目的 :了解顺铂 (DDP)引起卵巢癌细胞COC1、COC1/DDP细胞周期变化及凋亡规律。方法 :用光镜、电镜及流式细胞术等方法观察细胞凋亡规律及进行细胞周期分析。结果 :DDP引起COC1、COC1/DDP细胞周期变化主要表现为S期阻滞 ,P <0 .0 1;细胞死亡方式主要是凋亡 ,凋亡细胞发生在S期 ,P <0 .0 1;COC1、COC1/DDP细胞凋亡率不同 ,COC1凋亡率高 ,两组相比差异有显著性 (P <0 .0 1)。结论 :DDP引起COC1、COC1/DDP细胞S期阻滞、S期细胞凋亡 ,细胞凋亡与获得性耐药有关 相似文献
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耐甲氧西林葡萄球菌HVR基因分型及其与耐药性的关系 总被引:3,自引:0,他引:3
目的 为获得成都地区耐甲氧西林葡萄球菌的HVR-PCR基因型,比较HVR基因型与耐药谱的关系,从而指导临床合理选用抗生素,并初步探讨其在分子流行病学分析中的作用。方法 从成都地区四家三甲医院收集到临床分离的葡萄球菌114株。其中86株MRSA、10株MRSE(Mc‘S.epidemidis)、5株MSSE(Mc‘S.epidemidis)、8株MRSH(Mc‘S.haemolyticus)和5株MSSH(Mc‘S.haemolyticus)。用琼脂平皿二倍稀释法测定其MIC值,优良的碱裂解法提取DNA,应用PCR技术,扩增mec基因高变区(HVR区),聚丙烯酰胺凝胶垂直板和琼脂糖凝胶电泳分型。结果 根据PCR产物片段大小,MRSA、MRSE和MRSH分别被分为4种、3种和2种基因型,其中有9株MRSE的PCR扩增产物片段大小与MRSA相同。MRSA主要为A、D型,分别占52.32%和39.53%;B、C型最为耐药,而D型对多种药物敏感。MRSE的Ⅰ型为高度多重耐药株,而Ⅲ型对多种抗生素敏感。MRSH的a型比b型耐药。结论 HVR-PCR法对于由MRSA引起的院内感染的流行病学调查是一种快速、简单、可靠的分型法,且有利于抗菌药物的选用。这种方法能够部分比较MRSA菌株和耐甲氧西林的凝固酶阴性葡萄球菌(Mc‘CNSt)的mec决定因子,从而探讨其起源。 相似文献
104.
Effect of photobiomodulation on CCC-ESF reactive oxygen species steady-state in high glucose mediums
Chen Hongli Tu Mengru Shi Jia Wang Yunhao Hou Zhenhao Wang Jinhai 《Lasers in medical science》2021,36(3):555-562
Lasers in Medical Science - Delayed wound healing is one of the most challenging complications of diabetes mellitus (DM) in clinical medicine, and it is related to the excessive generation of... 相似文献
105.
Matthias Lngin Bruno Reichart Stig Steen Trygve Sjberg Audrius Paskevicius Qiuming Liao Guangqi Qin Maren Mokelke Tanja Mayr Julia Radan Lara Issl Ines Buttgereit Jiawei Ying Ann Kathrin Fresch Alessandro Panelli Stefanie Egerer Andrea Bhr Barbara Kessler Anastasia Milusev Riccardo Sfriso Robert Rieben David Ayares Peter J. Murray Reinhard Ellgass Christoph Walz Nikolai Klymiuk Eckhard Wolf Jan‐Michael Abicht Paolo Brenner 《Xenotransplantation》2021,28(1):e12636
106.
Tanaz Vaghaiwalla Brian Ruhle Kelvin Memeh Peter Angelos Edwin Kaplan Chih-Yi Liao Blase Polite Xavier Keutgen 《Surgery》2021,169(1):162-167
BackgroundPeptide receptor radionuclide therapy is a targeted therapy used to treat unresectable somatostatin receptor-positive neuroendocrine tumors. The objective of this study was to evaluate response rates among neuroendocrine tumors of different primaries and identify factors relevant to future treatment strategies.MethodsWe retrospectively reviewed patients who received peptide receptor radionuclide therapy for neuroendocrine tumors from 2018 to 2019 at our institution. Patients were assessed with computed tomography/magnetic resonance imaging and 68Ga-DOTATATE-positron emission tomography before and after 2 or 4 cycles of peptide receptor radionuclide therapy. Tumor response was evaluated by RECIST 1.1. Statistics included multinomial logistic regression models and Fisher exact test.ResultsTwenty-seven patients underwent 92 cycles of peptide receptor radionuclide therapy: pancreas (n = 11), small bowel (n = 7), and other (n = 9) neuroendocrine tumors. Overall, 30% (8 of 27) had partial response, 59% (16 of 27) stable disease, and 11% (3 of 27) progressed. Pancreatic neuroendocrine tumors responded differently from small bowel neuroendocrine tumors regardless of cycle number (P = .01). The majority of pancreatic neuroendocrine tumors (6 of 11) had partial response to peptide receptor radionuclide therapy, while all small bowel neuroendocrine tumors had stable disease. Pancreatic neuroendocrine tumors stable after 2 cycles were more likely to respond to additional cycles versus other neuroendocrine tumors (probability: 60% vs 11%).ConclusionPatients with unresectable advanced or metastatic pancreatic neuroendocrine tumors may benefit from a full course of peptide receptor radionuclide therapy, whereas other neuroendocrine tumors appear less likely to respond. Large prospective studies are needed to confirm these findings. 相似文献
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109.
本文应用免疫细胞化学及NSE-ELISA方法观察了一氧化氮对体外培养脊髓和背根神经节神经元的存活及对活性的影响。结果表明:一氧化氮合酶抑制剂N-Arg组(100、200μmol/L)NSE免疫反应阳性神经元数目、面积(AF值)及活性(OD值)明显大于空白对照组(P<0.01)。而一氧化氮合酶底物L-Arg组(1mmol/L)神经元面积积分和活性则小于对照组(P<0.01)。L-Arg的细胞毒性作用可为N-Arg逆转。 相似文献
110.
Petal-like apatite formed on the surface of tricalcium phosphate ceramic after soaking in distilled water 总被引:7,自引:0,他引:7
In the present study six types of tricalcium phosphate ceramic were prepared and soaked in distilled water for different periods to investigate whether a surface apatite layer was formed on TCP ceramics or not. X-ray diffractometry (XRD) and Fourier-transformed infrared (FTIR) spectrometer were used to examine the changes in crystalline phases and functional groups of TCP ceramics for different soaking periods. Calcium and phosphate ions released from TCP ceramics during soaking were recorded by atomic absorption analysis and ion-coupled plasma. Results revealed that alphaTCP, alphaTCP/betaTCP mixture (alphabetaTCP) and betaTCP ceramic were gradually dissolved. There was no apatite layer formed on their surface after being immersed in distilled water for different durations of time. Mg-TCP ceramic, tricalcium phosphate doped with Mg ions, exhibited a lower dissolution rate than the other types of TCP ceramics. Apatite crystals were also not formed on the surface of Mg-TCP ceramic when immersed in distilled water. Tribasic calcium phosphate, prepared from wet precipitation method, was converted to betaTCP/HAP (HbetaTCP) or alphaTCP/betaTCP/HAP (HalphabetaTCP) crystalline composition at different sintering temperatures (1,150 degrees C and 1,300 degrees C). The surface apatite layer did not appear on HbetaTCP ceramic after soaking. We observed that petal-like apatite was formed on the HalphabetaTCP ceramic surface after being immersed for 2 weeks. alphaTCP phase of HalphabetaTCP ceramic was not directly converted to apatite during soaking. The surface apatite layer formed on the HalphabetaTCP ceramic surface was due to the precipitation of the calcium and phosphate ions released from alphaTCP dissolution. HAP, which existed in the structure of HalphabetaTCP ceramic, plays a role as apatite-precipitating seed to uptake calcium and phosphate ions. TCP ceramics which lacked alphaTCP and HAP content neither converted to apatite nor formed surface apatite on their surfaces during immersion. 相似文献