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31.
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女性尿道括约肌控尿和压力性尿失禁发病的机制 总被引:2,自引:0,他引:2
杜广辉 《临床泌尿外科杂志》2007,22(4):241-243
女性尿道括约肌控尿机制和压力性尿失禁发病机理的研究经历了长期和曲折的过程,目前认为,女性尿道括约肌是由尿道横纹肌括约肌、尿道平滑肌括约肌和尿道固有膜等结构,共同参与组成的一个构造精细而有序的尿道括约肌复合体或称尿道括约肌系统.压力性尿失禁的发生主要与尿道括约肌本身解剖结构和功能缺陷,以及尿道周围附属结构和支撑结构缺陷有关. 相似文献
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目的:筛选膀胱癌预后相关基因,建立膀胱癌预后评分模型。方法:通过UCSC Xena平台下载癌症基因组图谱(TCGA)数据库、基因型和基因表达量关联数据库(GTEx)中406例膀胱癌患者的临床信息和膀胱癌组织RNA测序数据,以及28名健康对照者正常膀胱组织RNA测序数据。采用加权基因共表达网络分析(WGCNA)、单因素Cox回归分析、LASSO回归分析和多因素Cox回归分析筛选膀胱癌预后相关基因并建立预后模型,结合Kaplan-Meier生存曲线、受试者操作特征曲线(ROC曲线)验证模型的准确性。结果:分析得到膀胱癌相关差异表达基因共2308个。WGCNA拟合得到6个基因模块,筛选出对膀胱癌预后有显著作用的基因829个。运用单因素Cox回归与LASSO回归分析筛选出24个与膀胱癌患者预后相关的基因,多因素Cox回归分析训练集数据得到9个作为独立预测因子的基因,分别是 ADCY9、 MAFG_DT、 EMP1、 CAST、 PCOLCE2、 LTBP1、 CSPG4、 NXPH4、 SLC1A6,以此建立膀胱癌患者预后预测模型。训练集中高风险组和低风险组3年存活率分别为31.814%和59.821%,测试集中高风险组和低风险组3年存活率分别为32.745%和68.932%,模型预测训练集和测试集患者预后的ROC曲线下面积均在0.7以上。 结论:本研究建立的模型对膀胱癌高风险和低风险人群的生存情况具有较好的预测能力。 相似文献
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Ru-Jin Huang Thorsten Hoffmann Jurgita Ovadnevaite Ari Laaksonen Harri Kokkola Wen Xu Wei Xu Darius Ceburnis Renyi Zhang John H. Seinfeld Colin ODowd 《Proceedings of the National Academy of Sciences of the United States of America》2022,119(32)
The gas-phase formation of new particles less than 1 nm in size and their subsequent growth significantly alters the availability of cloud condensation nuclei (CCN, >30–50 nm), leading to impacts on cloud reflectance and the global radiative budget. However, this growth cannot be accounted for by condensation of typical species driving the initial nucleation. Here, we present evidence that nucleated iodine oxide clusters provide unique sites for the accelerated growth of organic vapors to overcome the coagulation sink. Heterogeneous reactions form low-volatility organic acids and alkylaminium salts in the particle phase, while further oligomerization of small α-dicarbonyls (e.g., glyoxal) drives the particle growth. This identified heterogeneous mechanism explains the occurrence of particle production events at organic vapor concentrations almost an order of magnitude lower than those required for growth via condensation alone. A notable fraction of iodine associated with these growing particles is recycled back into the gas phase, suggesting an effective transport mechanism for iodine to remote regions, acting as a “catalyst” for nucleation and subsequent new particle production in marine air.Marine aerosol formation contributes significantly to the global radiative budget given the high susceptibility of marine stratiform cloud radiative properties to changes in cloud condensation nuclei (CCN) availability. Atmospheric new-particle-formation is thought to involve nucleation of sulfuric acid with water, ammonia, or amines followed by condensation/growth in the presence of organic vapors (1, 2). Unique in the marine boundary layer (MBL), new particle formation involves sequential addition of HIO3 or clustering of iodine oxides (IxOy) (3, 4). In specific source regions such as coastal zones, seaweed beds, or snowpack/pack-ice, iodine oxide nucleation can be a driving force for nucleation (5–7). Over Arctic waters, nonetheless, one study finds insufficient iodic acid vapors to grow nucleated particles to CCN sizes (8), whereas another study finds that both nucleation and growth are almost exclusively driven by iodic acid (9). Over the open ocean, the supply of iodine oxides has been thought to be limited; however, recent measurements suggest that significant reactive iodine chemistry can occur in these regions (10). Moreover, observational evidence exists for open ocean particle formation and growth, especially when oceanic productivity is high (11, 12). An increase in atmospheric iodine levels in the North Atlantic since the mid-20th century has been shown to be driven by growth of anthropogenic ozone and enhanced subice phytoplankton production (13). While the reported IO concentration (0.4–3.1 ppt) in the remote MBL (10, 14, 15) is likely sufficient for formation of prenucleation clusters (∼1 nm), growth of these initial clusters requires the presence of other condensable vapors (16). Since preexisting aerosol particles act as a strong sink for the nucleated clusters, thus inhibiting atmospheric aerosol and CCN formation (17, 18), this early growth phase is essential for their survival. Whereas sulfuric acid vapor is also involved in nucleation, its level in remote open ocean is generally too low (105 molecules cm−3) to support subsequent particle growth, leaving organic vapors as the most plausible alternative for particle growth.In the marine atmosphere, condensing organics must originate from the oxidation of marine volatile organic compounds (VOCs), which predominantly comprise C1–C5 VOCs (e.g., isoprene) released from phytoplankton. Principal high volatility oxidation products consist of intermediate oxidized organics (IOOs), such as polyhydric alcohols (e.g., tetrols) or polyfunctional carbonyls (e.g., glyoxal) (19–22). Nonetheless, growth of available prenucleation clusters/nanometer particles requires condensing organic molecules of low effective volatilities (i.e., saturation mass concentration, C* < ∼10−3 μg m−3); otherwise, preferential condensation of the organic mass to larger-diameter particles would occur (23, 24). Formation of such extremely low-volatility organic compounds (ELVOCs) from gas-phase reaction is well established for monoterpene oxidation products (25, 26).A potential pathway for formation of low-volatility organics could also result from particle-phase chemical reactions induced by iodine oxides in the early stages of marine particle formation. When the underlying chemistry is sufficiently fast, kinetic condensation occurs, resulting in particles with diameters smaller than about 50 nm growing at the same rate (e.g., nm h−1) (24). If, however, particle-phase chemistry is preferentially favored in the smallest particles (i.e., stemming from the higher relative concentration of iodine oxides in freshly formed marine particles), growth of the nucleated particles could proceed more rapidly, as compared to that in which gas-phase chemistry is the source of the low-volatility compounds (23).In this paper, we present experimental results from field measurements as well as laboratory studies of nanometer particle growth and derive a plausible chemical mechanism from the results that can explain the observations of ultrafine particle growth in the marine atmosphere. The results suggest that both iodine and condensed organics contribute to particle growth from a nascent nucleation mode into an ultrafine particle mode. Moreover, laboratory studies of the growth of seed iodine oxide particles (IOP) via heterogeneous reactions with organic vapors suggest a hitherto unrecognized mechanism that fast-tracks the growth of nucleation mode clusters into survivable aerosol particles. In this process, a notable fraction of the iodine associated with these growing particles is recycled back to the gas phase, suggesting a transport mechanism for iodine to remote regions. 相似文献
37.
目的:观察电针疗法对广泛性子宫切除术后膀胱功能恢复的疗效。方法:将110例广泛性子宫切除术后患者随机分为电针组和常规组,各55例。常规组采用常规方法留置尿管和膀胱冲洗,第8天起每天用TDP照射腹部30 min,连续5天。电针组在常规组基础上,于术后第8天-第12天采用电针治疗,穴取三阴交、足三里、外关、水道、归来等。比较2组患者术后膀胱功能恢复的时间、尿动力学检查结果和住院天数。结果:电针组术后第14天膀胱功能恢复、尿潴留、尿失禁人数分别为51例(51/55)、4例(4/55)、0例,第28天分别为53例(53/55)、2例(2/55)、0例;常规组第14天分别为27例(27/55)、25例(25/55)、3例(3/55),第28天分别为43例(43/55)、11例(11/55)、1例(1/55),2组比较差异有统计学意义(P<0.01)。术后第14天膀胱功能恢复者残余尿量、膀胱容量、平均尿流率比较,电针组均优于常规组(P<0.01或P<0.05);电针组术后住院天数为(21.1±3.3)天,常规组为(25.5±3.5)天,电针组明显短于常规组(P<0.01)。结论:电针疗法可以促进广泛性子宫切除术后膀胱功能的及早恢复,缩短导尿管留置时间,有益于降低泌尿系统感染发生率和缩短住院天数。 相似文献
38.
邝焕容 《国际医药卫生导报》2017,23(20)
目的 探讨腹腔镜下结肠癌术后镇痛期间拔除尿管对患者尿潴留及相关并发症的影响.方法 分析本院2014年1月至2015年12月腹腔镜下结肠癌术后留置镇痛泵的患者46例,其中实验组23例(留置镇痛泵期内拔除尿管),对照组23例(停用镇痛泵后拔除尿管).两组术后尿潴留率、尿路感染率、肺部感染率、伤口感染率及满意率等指标比较.结果 两组患者的尿潴留率(8.7%比4.3%)、肺部感染率(4.3%比8.7%)、伤口感染率(4.3%比13.0%),差异均无统计学意义(均P>0.05).两组患者均未出现导尿管相关性尿路感染.实验组满意率78.3%高于对照组47.8%,差异有统计学意义(P<0.05).结论 腹腔镜下结肠癌术后留置镇痛泵的患者早期拔除尿管是安全可行的,且能减轻留置尿管引起的不适. 相似文献
39.
目的:探讨开塞露灌肠对产后尿潴留的临床应用价值。方法:对60例产后尿潴留患者,随机抽取32例为治疗组,28例为对照组。治疗组用开塞露保留灌肠治疗尿潴留;对照组单纯采用新斯的明肌肉注射。结果:治疗有效率治疗组为100%,对照组为64.3%,P<0.01。结论:开塞露灌肠效果明显高于单纯注射新斯的明,两组有显著差异。 相似文献
40.
刘乃丰 《Acta pharmacologica Sinica》1994,(2)
本文用放射配体法观察了维拉帕米(Ver)对恒河猴肾上皮细胞LDL受体活性的影响,发现Ver以浓度和时间依赖的方式明显增强受体介导的结合和内移过程,对降解的影响不显著。Ver作用浓度为44 mmol·L~(-1)效应最明显。 相似文献