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991.
本文通过28例正常人及28例癌症病患者的头发的分析,得出癌症病患者的头发区别于正常人的头发的特征是:癌症病患者的头发中含有微量元素As、Ni、Mn。 相似文献
992.
Ninety diffuse large-cell lymphomas (diffuse histiocytic lymphoma) were subclassified into B-cell, T-cell, and histiocytic types according to their enzyme histochemical and immunohistochemical characteristics. The B-cell type was characterized by presence of intracellular monoclonal immunoglobulin; negative or weakly positive diffuse acid phosphatase activity; and an occasional focal nodular pattern or preceding nodular lymphoma. The T-cell type was characterized by moderate, focal acid phosphatase activity; convoluted nuclear structure; and frequent preceding cutaneous manifestations. The histiocytic type was characterized by strong nonspecific esterases and diffuse acid phosphatase activity and presence of lysozyme and phagocytic activity. Most of the lesions (74 cases) were of the B-cell type. This group was further subdivided into follicular center cell type and B-cell immunoblastic sarcoma, according to the stage of cellular transformation. Preliminary clinical correlation suggests that the histiocytic type is most resistant to treatment. B-cell immunoblastic sarcomas were much more aggressive than neoplasms of the follicular center cell type. 相似文献
993.
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995.
体外反搏对血液流变性和血小板聚集性的影响 总被引:2,自引:0,他引:2
观察40例心脑血管疾病患者体外反搏前后血液流变性和血小板聚集性变化。结果表明,反搏后全血比及还原比粘度、血浆粘度有不同程度的下降(P<0.05~0.01)。反搏治疗后,1~5min血小板聚集率、最大聚集率和最大聚集速度较反搏前均明显降低(P<0.05~0.01),而5min解聚率则明显增加(P<0.05)。提示体外反搏治疗不仅影响血液动力学,而且明显降低血液粘度,对血小板聚集功能有明显抑制作用。 相似文献
996.
997.
The medullary raphe (MR) and the retrotrapezoid nucleus (RTN) in the ventral medulla are two of many central chemoreceptor sites. We examine their combined function in conscious rats by focal inhibition using microdialysis. Inhibition of RTN neurons with the GABAA receptor agonist muscimol, with simultaneous dialysis of artificial cerebrospinal fluid (ACSF) in or near to the caudal MR, causes hypoventilation (decrease in the ratio of minute ventilation to oxygen consumption, ) and reduces the ventilatory response to 7% CO2 by 24%. Inhibition of caudal MR serotonergic neurons with the 5-HT1A receptor agonist ( R )-(+)-8-hydroxy-2(di- n -propylamino)tetralin (8-OH-DPAT), with simultaneous dialysis of ACSF in or near to the RTN, causes hypoventilation but has no significant effect on the CO2 response. Inhibition of both the RTN and the caudal MR simultaneously produces enhanced hypoventilation and a 51% decrease in the CO2 response. The effects of treatment on the CO2 response are similar in wakefulness and in non-rapid eye movement sleep. Comparison of the effect of 8-OH-DPAT microdialysed into a more rostral portion of the MR, where the CO2 response is reduced by 22%, demonstrates heterogeneity within the MR of the function of serotonergic neurons in breathing. We conclude that serotonergic neurons within the caudal MR provide a non-CO2 -dependent tonic drive to breathe and potentiate the effects of RTN neurons that contribute to a resting chemical 'drive to breathe' as well as the response to added CO2 . These effects of caudal MR serotonergic neurons could be at a chemoreceptor site, e.g. the RTN, or at 'downstream' sites involved in rhythm and pattern generation. 相似文献
998.
肝素酶和碱性成纤维细胞生长因子与非小细胞肺癌转移和预后的关系 总被引:6,自引:0,他引:6
目的 探讨肝素酶(heparanase)和碱性成纤维细胞生长因子(bFGF)在人非小细胞肺癌(NSCLC)组织中表达的临床意义及其与肺癌转移和预后的关系。方法 采用免疫组织化学、原位杂交和Western blot方法,检测115例人NSCLC石蜡切片和45例新鲜肺癌及对应癌旁正常组织中肝素酶和bFGF的表达情况。采用χ^2检验、t检验、生存曲线和Cox比例风险回归等方法分析肝素酶和bFGF分别表达及共表达的意义。结果 免疫组织化学染色证实肝素酶(91/115)和bFGF(89/115)主要表达在癌细胞质和(或)细胞膜中,在正常肺泡上皮和支气管上皮中则呈阴性表达。Western blot也证实肝素酶在肺癌中的表达明显增高(P=0.041)。统计分析结果显示:肝素酶和bFGF的表达具有明显的一致性(P:0.0001),二者单独表达和共表达均与肺癌的分期、血管侵袭、淋巴结转移、微血管密度和预后有关,其中,二者共表达时与分期和微血管密度的相关性更显著;另外,bFGF还与肺癌的分化程度有关。多因素分析结果显示,肺癌的分化程度、血管浸润、淋巴结转移和bFGF的表达可以作为判断肺癌预后的危险因素,但肝素酶不是影响预后的独立因素。结论 肝素酶和bFGF均与肺癌的转移、血管生成和预后密切相关。 相似文献
999.
人类白细胞抗原-G突变体cDNA克隆及在K562细胞上的表达 总被引:2,自引:0,他引:2
目的:克隆人类白细胞抗原-G(Human leukocyte antligen-G,HLA-G)突变体cDNA,并使其在HLA-I类阴性的K562细胞上获得稳定表达,为研究配-受体之间的识别机制奠定基础。方法:用RT-PCR方法从人子宫蜕膜组织扩增出HLA-GcDNA,得到全长HLA-GPCR产物后,用桥式PCR方法进行定点点突变,将突变的目的基因亚克隆于逆转录,将突变的目的基因亚克隆于逆转录mG-pLNCX表达载体,采用感染的方法将重组质粒转入K562细胞,最后经G418筛选及有限稀释,利用单克隆抗体W6/32进行FACS及mRNA检测,观察HLA-G突变体在靶细胞表面的表达。结果:HLA-G突变体分子在经mG-pLNCX转染的靶细胞表面获得稳定高表达。结论:成功构建了mG-pLNCX表达载体,并使HLA-G突变体分子在HLA-I类阴性的靶细胞K562细胞上获得稳定表达。 相似文献
1000.
Jian-Zhong Zhang Li Jing Feng-Ying Guo Yi Ma Yi-Li Wang 《Experimental and toxicologic pathology》2007,59(3-4):227-235
To determine if the inhibitory effects of ketamine on the extracellular signal-regulated kinase (ERK) 1/2 are involved in reduction of the hyperglycemia-exaggerated cerebral ischemic lesion, rats with normoglycemia, hyperglycemia, or hyperglycemia supplemented with ketamine were subjected to 15 min of forebrain ischemia, and then, reperfusion for 0.5, 1, and 3h. Phosphorylation of ERK1/2 in the brain tissues was assessed by immunohistochemistry and Western blot analysis. In rats with normoglycemia, we demonstrated a moderate increase of the ERK1/2 phosphorylation in the cingulum cortex and hippocampus CA3 following an ischemic intervention. It quickly dropped to control levels after reperfusion for 0.5h. In rats with hyperglycemia, however, the increase of the ERK1/2 phosphorylation in these areas was significantly higher in all animals reperfused. The neuronal death, detected by the TdT-mediated-dUTP nick end labeling assays, was found in the cingulum cortex (5.23+/-2.34, per high power feild) and hippocampus CA3 areas (6.29+/-3.68, per 1mm(2)) in hyperglycemic group after reperfusion for 3h. With ketamine treatment, the ERK1/2 phosphorylation in cingulum cortex and hippocampus CA1 and CA3 areas was found to be the same as that in normoglycemia rats. Our results suggest that hyperglycemia may increase the ischemic insult through modulation of the signal transduction pathways involving ERK1/2. The inhibitory effects of ketamine on the hyperglycemia-activated ERK1/2 phosphorylation are probably through inhibition of the N-methyl d-aspartate-mediated calcium influx, which subsequently reduce the hyperglycemia-exaggerated cerebral damage. 相似文献