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101.
Postnatal development of nicotinamide adenine dinucleotide phosphate-diaphorase-positive neurons in the retina of the golden hamster 总被引:1,自引:0,他引:1
The histochemical method was used to investigate the postnatal development of nicotinamide adenine dinucleotide phosphate-diaphorase (NADPH-d) -positive neurons in retinas of the golden hamster. NADPH-d-positive neurons were discernible in the retina at postnatal day (P)1. From P4 onward to adulthood, when the retina acquired its laminated characteristics, NADPH-d- positive neurons were observed in the inner nuclear layer (INL) and the ganglion cell layer (GCL). Results showed that NADPH-d-positive neurons in INL and GCL followed different time courses and patterns in their development. NADPH-d-positive neurons in INL underwent a sharp increase from P4 to P8 (3.6-fold), followed by a decrease to 46% of the maximum at P12. This value was maintained relatively constant to the adult level. The mean diameters of NADPH-d-positive neurons in INL, which were smaller than those in the GCL for all ages, increased from P8 to P12 and from P20 to adulthood. As for neurons in the GCL, the increase in cell number was not so apparent for the earlier postnatal days until P20; thereafter, an obvious increase to the adult level was observed. The mean diameters of the NADPH-d-positive cell bodies in the GCL increased with age, except for P16-P20, during which time there was a slight and insignificant decrease. The tendency of changes in cell density was basically similar to that of the total number for both the INL and the GCL. Between P12 and P20, the density distribution map of the NADPH-d-positive neurons underwent dramatic changes: The highest density shifted from the upper central retina at the earlier postnatal days to the lower central retina in the adult. The two waves of increase in NADPH-d-positive neurons coincide with the process of axonal elongation and synaptogenesis and the acquisition of visual function and experience. It is suggested that these NADPH-d-positive neurons are related to these two developmental events. 相似文献
102.
Pentoxifylline attenuated the renal disease progression in rats with remnant kidney 总被引:12,自引:0,他引:12
Lin SL Chen YM Chien CT Chiang WC Tsai CC Tsai TJ 《Journal of the American Society of Nephrology : JASN》2002,13(12):2916-2929
Previous studies have reported that pentoxifylline, a phosphodiesterase inhibitor, attenuates experimental mesangial proliferative glomerulonephritis. This study hypothesized that pentoxifylline could also attenuate the renal disease progression in rats with remnant kidney. After 5/6 subtotal nephrectomy, rats developed progressively elevated proteinuria and plasma creatinine, glomerulosclerosis, interstitial inflammation, and fibrosis, all of which were attenuated by 40 to 60% by pentoxifylline. However, the elevated BP was not changed by pentoxifylline. Pentoxifylline reduced the upregulation of monocyte chemoattractant protein-1 gene by 60% in the cortex of remnant kidney, as well as in a dose-dependent manner in the albumin- or angiotensin II-stimulated proximal tubular cells. It also reduced the upregulation of mitogenic and profibrogenic genes by 50%, including platelet-derived growth factor, fibroblast growth factor-2, transforming growth factor-beta(1), connective tissue growth factor, and types I and III collagen in the cortex of remnant kidney. Furthermore, pentoxifylline was found to decrease the numbers of interstitial myofibroblasts by 60% in the cortex of remnant kidney and suppress the proliferation of cultured interstitial fibroblasts. It also reduced the angiotensin II-induced or transforming growth factor-beta(1)-induced expression of connective tissue growth factor gene in cultured fibroblasts and mesangial cells. Combining pentoxifylline with an angiotensin-converting enzyme inhibitor, cilazapril, almost completely attenuated the renal disease progression in rats with remnant kidney. In conclusion, pentoxifylline alone can attenuate the chronic renal disease progression. Its combination with cilazapril has the potential to prevent the renal disease progression almost completely. 相似文献
103.
珠海口岸首次截获褐带蠊 总被引:2,自引:0,他引:2
珠海出入境检验检疫局于2003年8月29日从1艘巴拿马籍货轮上捕获1只雌性褐带蠊成虫Supella longipalpa(Fabricius,1798)。该种蜚蠊起源于非洲,在美国是常见室内种,在我国罕见。其主要特征为:有2条淡褐色带状横斑位于翅基部和腹部,因此俗称其为“褐带蠊”。为防止该蜚蠊通过国际航行船舶传入我国,对褐带蠊的形态特征进行描述,以供口岸检疫人员和昆虫研究人员鉴别之用。 相似文献
104.
目的探讨白细胞介素-6(IL-6)和肿瘤坏死因子(TNF)在脑梗死过程中所起的作用和临床意义。方法采用ELISA方法测定42例脑梗死患者和40例同龄健康体检者血清IL-6和TNF含量,并分析它们与梗死体积的关系。结果急性脑梗死患者血清IL-6和TNF明显高于对照组,它们与脑梗死体积存在明显相关性。结论IL-6和TNF参与了急性脑梗死的发生发展。 相似文献
105.
106.
The present study observed the effects of superoxide diamutase (SOD) and its Inhibitor, diethyldithiocarbamate (DDC), on the metastasis of Lewis Lung cancer and some biological characteristics of A548 lung cancer cell line. It was found that SOD and DDC inhibited significantly the metastasis of Lewis lung cancer In C57 BL mice, which the effect of DDC was more significant than that of SOD, and decreased the proliferation of A549 lung cancer cell and its transplantation rate in nude mice. 相似文献
107.
白酒中敌敌畏的固相微萃取 总被引:3,自引:0,他引:3
用大口径毛细管柱气相色谱法、氢焰离子化检测器进行分析测定。该方法在0.5~12mg/L浓度范围内有很好的线性关系。相关系数为0.9983;最低检测浓度可达0.05mg/L。本方法把样品的萃取浓缩与进样分析一体化完成。整个分析过程不使用任何萃取溶剂 相似文献
108.
109.
110.
Biocompatibility of NGF-grafted GTG membranes for peripheral nerve repair using cultured Schwann cells 总被引:6,自引:0,他引:6
We previously developed a biodegradable composite with potentially good biocompatibility composed by tricalcium phosphate and gluataraldehyde cross-linking gelatin (GTG) with good mechanical property feasible for surgical manipulation. The purpose of this study was to evaluate the feasibility of immobilizing nerve growth factor (NGF) onto the composite (GTG) with carbodiimide (GEN composite). Cultured Schwann cells were seeded onto the GTG and GEN composites. For comparison, GTG membrane soaked in NGF solution without carbodiimide (GN composite) as cross-linking agent was also used to culture Schwann cells. Cell morphology was observed by a scanning electron microscope. Cell survival, cytotoxicity and cellular metabolism on the NGF-grafted GTG membrane were assessed quantitatively in terms of cell protein content, leakage of cytosolic lactate dehydrogenase (LDH) activity and by the well-established MTT assay, respectively. The result of LDH study did not show significant difference among GTG, NGF-modified GTG and control group. This indicated that GTG composite, whether cross-linking with NGF or not, has little cytotoxic effect. Comparing the protein content and MTT assay among GEN, GN composite and control group, the data confirmed more attachment of Schwann cells on GEN composite. Although GTG cross-linking with NGF did not promote Schwann cell proliferation, the techniques we used in this study provided a method to fabricate a novel biomaterial incorporation of Schwann cells and covalently immobilized NGF. 相似文献