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991.
992.
A possible role for nerve growth factor in the augmentation of sodium channels in models of chronic pain 总被引:5,自引:0,他引:5
Inflammation induces an upregulation of sodium channels in sensory neurons. This most likely occurs as a result of the retrograde transport of cytochemical mediators released during the inflammatory response. The purpose of this study was to determine the effect of the subcutaneous administration of one such mediator, nerve growth factor (NGF), on the production of sodium channels in neurons of the rat dorsal root ganglion. For this, hindpaw withdrawal from either a thermal or mechanical stimulus was measured in rats at selected intervals for up to 2 weeks following injections of NGF. Sodium channel augmentation was then examined in dorsal root ganglia using site-specific, anti-sodium channel antibodies. Both thermal and mechanical allodynia was observed between 3 and 12 h post-injection. The hyperalgesic response returned to baseline by approximately 24 h post-injection. Sodium channel labeling was found to increase dramatically in the small neurons of the associated dorsal root ganglia beginning at 23 h, reached maximum intensity by 1 week, and persisted for up to 3 months post-injection. Pre-blocking NGF with anti-NGF prevented the NGF-induced decrease in paw withdrawal latencies and significantly reduced the intensity of sodium channel labeling. The results indicate that NGF is an important mediator both in the development of acute hyperalgesia and in the stimulation of sodium channel production in dorsal root ganglia during inflammation. 相似文献
993.
Parathyroid hormone-related protein (PTHrP) and the PTH/PTHrP receptor are expressed in most normal tissues, including brain, where PTHrP is though to act locally in an autocrine or paracrine fashion. Previous in situ localization studies in adult rodents have documented CNS PTHrP expression in neurons but not in glial cells. However, a recent report describing immunoreactive PTHrP in human astrocytomas suggests that PTHrP expression may be a marker of dedifferentiation and/or malignant transformation in glial cells. To begin to test this hypothesis, constitutive and regulated PTHrP expression were examined in cultured fetal and transformed (U-373 MG) human astrocytes. PTHrP was expressed in untreated fetal astrocytes and U-373 MG cells, as determined by Northern analysis, immunocytochemical staining, and detection of PTHrP(1-84) protein in conditioned media. Epidermal growth factor and tumor necrosis factor, important growth factors in astrocyte development and malignant transformation, stimulated PTHrP expression in both cell types. Treatment of U-373 MG cells or fetal astrocytes with PTHrP(1-34) consistently inhibited cellular proliferation, as measured by [(3)H]-thymidine incorporation. These findings suggest that PTHrP, a peptide whose expression is induced by mitogens in both immature and transformed human astrocytes, may feedback inhibit cellular proliferation, an effect that may be of importance during malignant transformation as well as CNS development. Furthermore, when combined with previous evidence of PTHrP expression by PTH/PTHrP receptor-positive neurons, our demonstration of regulated PTHrP expression by receptor-positive astrocytes identifies PTHrP as a potential peptide mediator of cross-talk between glial cells and neurons. 相似文献
994.
Proliferation, Vascular Endothelial Growth Factor Expression and Cavernous Sinus Invasion in Growth Hormone Secreting Pituitary Adenomas 总被引:4,自引:0,他引:4
Summary Surgical cure of growth hormone producing pituitary adenomas (GHomas) becomes difficult when they invade the cavernous sinus
(CS). Tumour proliferative activity and angiogenesis are thought to be required for tumour growth and invasion, and vascular
endothelial growth factor (VEGF) activates neovascularization around tumours. In this study, the mechanism and clinical significance
of CS invasion is analysed. In 25 surgically treated GHomas, the extent of CS invasion was classified as high (Knosp's grade
3 and 4), and low (grade 0, 1 and 2) MR grades, and the MR grades were compared with tumour proliferative potential (Ki-67
expression), angiogenetic demand (VEGF expression), volume of adenomas and serum hormone levels.
The Ki-67 index of high MR grade adenomas (1.17±0.62%) was significantly higher than that of low MR grade adenomas (0.55±0.42%,
p=0.027), whereas VEGF expression showed no significant correlation with MR grades (p>0.999). Tumour volume also showed a
significant correlation with MR grade (p=0.002). VEGF expression was not correlated with serum hormone level and volume, but
was correlated with tumour proliferative potential. Proliferative potential and tumour volume were two independent factors
related to CS invasion. Although VEGF expression was not a direct factor related to CS invasion, it may indirectly play a
role in activation of tumour aggressiveness, which is required in CS invasion.
Our results show that high MR grade adenomas have higher proliferative ability. In order to improve the surgical outcome,
pre-operative medical debulking is indicated, particularly, in such adenomas. 相似文献
995.
目的 探讨胰岛素样生长因子-Ⅰ(IGF-1)和IGF-Ⅱ与胎儿生长发育的关系。方法 抽取15例分娩IUGR胎儿(IUGR组)及20例分娩正常Jk(对照组)产妇肘静脉血、新生儿脐静血及羊水。采用放射免疫法及免疫放射法分别测定其IGF-Ⅰ、IGF-Ⅱ水平。结果 IUGR组产妇血清IGF-Ⅰ水平低于对照组,IGF-Ⅱ水平无显著差异;IUGR组脐血及羊水中IGF-Ⅰ、IGF-Ⅱ水平较对照组显著降低。结论 检测母血及羊水中IGF-Ⅰ、IGF-Ⅱ水平可监测胎儿生长发育,早期诊断IUGR。 相似文献
996.
介绍成人生长激素缺乏症诊断与治疗方面的一些进展,强调动态试验对于诊断的作用及注意事项,与替代治疗相关的问题涉及剂量、疗程、对代谢的影响及治疗的安全性等. 相似文献
997.
锌与幼儿生长发育的关系 总被引:1,自引:0,他引:1
锌对儿童具有特别重要的意义 ,发锌是反映体内锌营养状况的指标之一。对 10 1名幼儿的发锌浓度及体格、智力、行为适应能力的测量结果分析显示 ,男孩的发锌与ADQ之间存在正相关 (r =0 4 0 5 2 ,P =0 0 0 70 ) ,发锌正常组的ADQ较发锌缺乏组高 12 71(95 %CI :0 5 5~ 2 4 87) ;但女孩的发锌与ADQ之间未见相关关系。发锌与幼儿所有的体格测量Z评分及IQ之间无明显的相关性。 相似文献
998.
目的探讨转化生长因子β1(TGF-β1)、血管紧张素II(AII)、醛固酮(ALD)及白介素1α(IL-1α)与原发性高血压(EH)左室重构的关系.方法选择EH患者50例[左室肥厚(LVH)28例,非LVH(NLVH)22例]同步检测血中TGF-β1、AII、ALD及IL-1α水平;用超声心动图仪测定并计算左室质量指数(LVMI).与对照组25例进行对比分析.结果 EH组血中TGF-β1、AII、ALD及IL-1α水平均较对照组显著增高(P<0.001),以LVH为甚.结论 TGF-β1、AII、ALD及IL-1α共同对EH患者的LVH造成影响. 相似文献
999.
脑溢安对试验性脑出血大鼠血管内皮生长因子表达的影响 总被引:5,自引:0,他引:5
目的 研究实验性脑出血大鼠脑内血管内皮生长因子 (VEGF)的时空分布及中药脑溢安的影响。方法 通过立体定位向脑内苍白球注入Ⅶ型胶原酶 0 .4U建立脑出血模型 ,运用免疫组化和原位杂交法检测脑出血后 3h、6h、12h、1d、4d、7d ,14d七个时间点VEGF的表达变化 ,以阳性细胞数作为观察指标。结果 脑出血 3hVEGF开始表达 ,6h增强 ,12h及 1d阳性细胞达到高峰 ,4d开始下降 ,到 7d和 14d仍有少量表达。脑溢安组在 6h、12h、1d、4d高于模型组 (P <0 0 5 )。结论 脑出血后脑内VEGF表达增加 ;脑溢安可上调脑出血后VEGF的表达 ,可能是其神经保护机制之一。 相似文献
1000.
宫颈阴道分泌物中IGFBF-1检测在延期妊娠引产中的临床价值 总被引:1,自引:0,他引:1
目的探讨检测胰岛素样生长因子结合蛋白-1(IGFBP-1)在延期妊娠引产中的临床价值.方法采用快速免役层析法检测202例延期妊娠孕妇宫颈阴道分泌物中的高磷酸化IGFBP-1, 并予以催产素引产.结果 IGFBP-1阳性组,3d内引产成功率91.20%;IGFBP-1阴性组,3d内引产成功率为41.80%.两结果比较差异有统计学意义(P<0.05).结论检测宫颈阴道分泌物中胰岛素样生长结合蛋白-1 可作为预测宫颈成熟的一个客观指标. 相似文献