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81.
聚合酶链反应检测细菌16S rRNA基因 总被引:2,自引:0,他引:2
根据细菌16SrRNA基因的高度保守性,设计合成所有细菌、革兰氏阳性细菌及革兰氏阴性细菌的共同引物,采用聚合酶链反应检测已知细菌13株,三对引物分别扩增的阳性率为100%,倍比稀释法能检出细菌的最低浓度为4CFU·ml-1,同时检测临床样本40份,阳性率为675%(27/40),同期细菌培养阳性率为45%(18/40),二者比较差异有显著性(P<0.05)。结果提示聚合酶链反应检测细菌16SrRNA基因具有高度的特异性和敏感性。 相似文献
82.
A 45-year-old male was admitted to our hospital for investigation of a nodular shadow in segment 5 of the right lung on a
chest computed tomogram. A right middle lobectomy with mediastinal lymph node dissection was performed under a diagnosis of
lung cancer, and histologic examination confirmed small cell carcinoma. There were sarcoid reactions in the resected lymph
nodes and the lung parenchyma, but no signs of systemic sarcoidosis were evident. Sarcoid reactions are rarely observed in
the regional lymph nodes draining malignant tumors. Moreover, while they are most common in squamous cell carcinoma of the
lung, they extremely rare in small cell carcinoma. To our knowledge, this is only the third report of this unusual entity
in the English and Japanese literature. 相似文献
83.
Changes in brain corticotropin-releasing factor messenger RNA expression in aged Fischer 344 rats 总被引:1,自引:0,他引:1
Adaptation in aging may become impaired from abnormal expression of corticotropin-releasing factor (CRF) and altered CRF receptor function. In this study, we measured CRF mRNA levels in Fischer 344 rats at various ages. The brains of these rats were processed for in situ hybridization. Relative to 3-month-old rats, levels of CRF mRNA were significantly decreased in the following brain areas at the following ages: at 24 months in the paraventricular hypothalamus, at 11, 17, and 24 months in the amygdala and at 17 and 24 months in the bed nucleus of the stria terminalis. These changes may contribute to impaired adaptations to stress, cognitive decline and other pathophysiological processes during aging. 相似文献
84.
85.
Merchant DJ 《The Prostate》1980,1(2):215-225
Immunological and biochemical probes for viral genomes and products, growth in cell culture, co-culture methods to activate latent genomes, use of activating agents, and electron microscopy have been used in efforts to demonstrate RNA viruses in prostate cancer. Despite findings of C-type particles and p30 antigens, the role of RNA viruses appears to be secondary, with activation of the virogene being a relatively uncommon occurrence. No compelling evidence for Herpes II or cytomegalovirus as etiologic agents has emerged, despite their common presence in the urogenital tract. Though the search for integration of fragments of viral genome into host DNA is still in progress, it appears unlikely that these viruses would account for a significant number of prostate carcinomas. Progress has been achieved in developing simple, reliable, primary culture methods for human prostatic tissue, using explants or dispersed cells. Three cell lines, all from metastatic foci, have been established, are characterized, and are available for distribution. One neonatal cell strain retains many properties of normal prostate. 相似文献
86.
Summary Incision wounds were made on the outer ear of rats and two biopsies were taken for examination after different survival times. In each case a biopsy was made of vital tissue and a second of postmortem tissue after refrigeration for 24 h. The biopsies were exposed to a solution containing the RNA precursor3H-cytidine for 1 h, washed and fixed in formalin. Sections 5 m thick were then autoradiographically prepared and automatically evaluated using Quantimet 920. The intravital specimens showed a significant increase in3H-cytidine incorporation in the basal cell layer after survival times of 10–24 h. No increase was seen in the stratum corneum, corium or cartilage tissue. The investigated distance from the wound margin did not have any significant bearing on the results. The3H-cytidine incorporation rate in postmortem tissue was practically identical with that of vital tissue, but no increase was observed in the rate of RNA synthesis in the basal cells as a function of the age of the wound. It may therefore be assumed that this method provides no additional information as to the age of wounds in postmortem examination.Dedicated to Professor O. Pribilla on the occasion of his 70th birthday 相似文献
87.
Dr. med K. -E. Sjølin 《Urological research》1982,10(5):245-248
Summary The correlations of Pseudouridine () values in 8 h and 24 h urinary samples from 23 healthy persons were determined. Pseudouridine in the 8 h urinary samples was measured by high-performance liquid chromatography and the 24 h excretion was calculated from the results of three 8 h determinations. Simultaneous determinations of urinary creatinine were performed by Jaffe's reaction. Based on the 8 h values of urinary Pseudouridine the results demonstrated a constant excretion of Pseudouridine in the 24 h periods, if the values were related to the urinary creatinine. The precision in using this ratio as an indicator for normal 24 h excretion of Pseudouridine was 90.5% for males and 92.5% for females. 相似文献
88.
The intravenous injection of the lighter lanthanide ions Pr(III), Nd(III), and Sm(III) in doses of 35 moles/kg inhibits, and isoosmolar doses of the heavier lanthanide ions Gd(III), Dy(III), and Er(III) stimulate rat liver nuclear in vitro RNA synthesis catalyzed by RNA polymerase B 24 h after their application, while nuclear RNA synthesis, catalyzed by RNA polymerase A, was inhibited by the same isoosmolar doses of Pr(III), Nd(III) and not influenced by Sm(III), Gd(III), Dy(III), or Er(III). The effect of in vivo applied Pr(III) and Nd(III) on rat liver in vitro nuclear RNA synthesis shows a similar time- and dose-dependent pattern.The decreased rat liver nuclear in vitro RNA synthesis 24 h after intravenous injection of Pr(III) as well as after Nd(III) was accompanied by a decreased nuclear in vitro 3H-acetate uptake by the chromatin-bound histone fractions, F 2a2, F 3, and F 2a1. At the same time after the Pr(III) injection, the capacity and number of initiation sites of the rat liver nuclear template for homologous nuclear RNA polymerases, prepared from control rat liver nuclei, was lower than the corresponding control template. A decreased activity of endogenous free nuclear RNA polymerases, as determined with the aim of the synthetic poly(dA-dT) template 24 h after Pr(III), may further contribute to the decreased nuclear RNA synthesis.The results indicate a primary ionic size-correlated interference of lanthanides with the nuclear control mechanisms of RNA synthesis. 相似文献
89.
鹿茸口服液促进RNA和蛋白质合成作用的研究 总被引:1,自引:0,他引:1
目的:研究鹿茸口服液对青年及老年小鼠RNA和蛋白质合成的作用。方法:观察口服鹿茸口服液对小鼠肝RNA和蛋白质含量及^3H-Uridine和^3H-Leucine掺入的影响。结果:鹿茸口服液可明显增加老年小鼠肝RNA和蛋白质含量及[^3H]Uridine和[^3H]Leucine掺入RNA和蛋白质,作用明显强于青年小鼠。结论:鹿茸口服液对老年小鼠RNA和蛋白质合成有明显促进作用。 相似文献
90.
目的 :筛选和克隆胃印戒细胞癌与正常胃黏膜细胞差异表达基因片段。方法 :采用mRNA差异显示法 (mRNAdifferentialdisplayPCR ,DD PCR) ,对比胃印戒细胞癌组织与正常胃黏膜组织mRNA的表达差异 ,克隆胃印戒细胞癌差异片段 ,经过RNA的斑点杂交、测序以及序列分析和同源性比较。结果 :胃印戒细胞癌与正常胃黏膜中存在明显的基因表达差异 ,发现与胃癌相关的差异表达条带 16条 ,其中 7条为缺失表达条带 ,9条为过度表达条带。对其中 4条差异表达条带进行克隆、测序 ,经序列分析及同源性比较和RNA的斑点杂交 ,表明确认其中 1条为GenBank/BLAST中尚未收录的片段。结论 :胃印戒细胞癌的mRNA差异显示证明 ,该EST序列可能在胃癌的发生发展中具有一定作用 相似文献