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排序方式: 共有1103条查询结果,搜索用时 0 毫秒
1.
目的总结75例不同病因引起脑积水的3种分流方法,以评价其临床疗效。方法分析75例脑积水形成的病因手术方法、手术结果、术后并发症等。结果除颅内肿瘤(5例)及术后癫痫致颅内出血(2例)共死亡7例外,手术疗效满意。但术后并发症以脑室心房分流术及脑室腹腔分流术后分流管堵塞的发生率较高。结论根据不同手术指征,选择不同分流方法,改进分流管,可减少手术损伤及术后分流管堵塞引流不畅等并发症。  相似文献   
2.
Cholinergic amacrine cells of the chicken retina were detected by immunohistochemistry using an antiserum against affinity-purified chicken choline acetyltransferase. Three populations of cells were detected: type I cholinergic amacrine cells had cell bodies on the border of the inner nuclear and inner plexiform layers and formed a prominent laminar band in sublamina 2 of the inner plexiform layer, while type II cholinergic amacrine cells had cell bodies in the ganglion cell layer, and formed a prominent laminar band in sublamina 4 of the inner plexiform layer. Type III cholinergic amacrine cell bodies were located towards the middle of the inner nuclear layer, and their processes were more diffusely distributed in sublaminas 1 and 3-5 of the inner plexiform layer. Type I and type II cells were present at densities of over 7000 cells/mm2 in central areas declining to less than 2000 cells/mm2 in the temporal retinal periphery. The cells were organized locally in a non-random mosaic, with regularity indices ranging from 3 peripherally to over 5 centrally. Neither at the light nor electron microscopic levels was a lattice of cholinergic dendrites of the kind reported by Tauchi and Masland [J. Neurosci. 5, 2494-2501 (1985)] detectable. Within the two prominent dendritic plexuses, a major feature of the synaptic interactions of the type I and type II cholinergic cells was extensive synaptic interaction between cholinergic processes. Apart from this, there was little, if any, input to cholinergic processes from non-cholinergic amacrine cells, but there was input from bipolar cells. Output from the cholinergic amacrine cell processes was directed towards non-cholinergic amacrine cells as well as other cholinergic amacrine cells, and ganglion cells.  相似文献   
3.
Histological and histochemical analyses were performed on the anterior latissimus dorsi muscle (ALD, red muscle) and the posterior latissimus dorsi muscle (PLD, white muscle) in normal (line 412) and dystrophic chickens (line 413) from 19 day embryos to 6 weeks of age. PLD, the white muscle, in dystrophic chickens showed higher percentages of red and intermediate fibres than those of normal chickens during the early development of muscles. Increases of the oxidative enzyme activities and the numbers of NADH--TR formazan granules in the white fibres of PLD were already found at 1 week of age in dystrophic chicken. Fibre types, oxidative enzyme activities and NADH--TR formazan granules showed no differences in ALD between normal and dystrophic chickens. These results suggest that increases of oxidative enzyme activities and formazan granule numbers and incomplete fibre type differentiation in PLD of dystrophic chickens are early pathological processes in such birds.  相似文献   
4.
Summary. XC cells are highly susceptible to syncytium formation by infection of ecotropic murine leukemia viruses (MLVs) and by expression of their envelope protein (Env). By this property, XC cells are widely used to determine titers of ecotropic MLVs. Number of plaques resulted from the syncytium formation in XC cells by ecotropic MLV infection is corresponding to number of the viral particles. XC cells had been established from a v-src-induced rat tumor. It has been reported that transformed cells are more sensitive to Mo-MLV-induced syncytium formation than non-transformed cells. To assess whether the transformation by v-src oncogene in XC cells is involved in the high sensitivity to ecotropic MLV-induced syncytium formation, XC cells were treated with genistein, a protein tyrosine kinase inhibitor. Genistein suppressed the syncytium formation between XC cells and ecotropic Env-expressing 293T cells. This result indicates that protein tyrosine kinase activity is associated with the high sensitivity of XC cells to ecotropic Env-induced syncytium formation.Received January 8, 2003; accepted May 26, 2003  相似文献   
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6.
E. coli was found to grow anaerobically on lactate in the presence of trimethylamine N-oxide (TMANO), reducing it to trimethylamine. Anaerobic growth on glucose was promoted in the presence of TMANO. When a culture grown in complex medium was transferred to defined medium, growth on glucose and ammonia took place in the presence of TMANO after consumption of complex nutrients introduced with the preculture, in contrast to growth in nitrate respiration. The amounts of ethanol, succinate, and lactate among the fermentation products were decreased and that of acetate was increased in the presence of TMANO. Formate generation was much reduced at pH 7.4, whereas stoichiometric formation of formate was observed in the absence of TMANO. Cells grown anaerobically in the presence of TMANO had a higher activity of amine N-oxide reductase than cells grown under other conditions. The content of cytochrome-558 was elevated in the presence of TMANO during growth in complex medium. Cytochrome c-552 found in cells grown in diluted complex medium or defined medium in the presence of TMANO was oxidized by TMANO in cell extracts. The molar growth yield on glucose was higher in the presence of TMANO than in its absence and lower than that in the presence of nitrate.  相似文献   
7.
鼻腔、咽部非霍奇金氏淋巴瘤   总被引:2,自引:0,他引:2  
目的 :探讨鼻腔、咽部非霍奇金氏淋巴瘤 ( NHL)的临床特征、诊断要点及误诊原因。方法 :对1 986年~ 1 996年住院的 2 4例鼻腔、咽部非霍奇金氏淋巴瘤的患者作一回顾性分析。结果 :2 4例临床表现差异较大 ,缺乏特征性的表现。首次诊断 NHL6例 ,其余 1 8例初诊时诊断 :慢性鼻炎 8例 ,恶性肉芽肿3例 ,鼻息肉 2例 ,鼻中隔粘膜肥厚 2例 ,扁桃体炎 2例 ,慢性咽炎 1例。 2 4例均经病理切片及免疫组化确诊。结论 :鼻腔、咽部非霍奇金氏淋巴瘤临床表现复杂 ,缺乏特征性 ,早期易误诊。提高临床医师对本病的认识 ,反复活检及免疫组化等方法有利于本病的确诊。  相似文献   
8.
STUDY OBJECTIVE--Intracoronary or intravenous adenosine during reperfusion in combination with lignocaine may attenuate "reperfusion injury" and limit myocardial infarct size in the canine heart. The aim of this study was to test whether intravenous adenosine also protects myocardium in the rabbit heart, which lacks xanthine oxidase and significant coronary collaterals in contrast to the canine heart. DESIGN--Five groups of rabbits underwent a 30 min occlusion of the circumflex coronary artery, followed by reperfusion. In adenosine treated groups, either a high dose of adenosine (0.37 mg.kg-1.min-1) with lignocaine treatment (5 mg intravenously 1 min before coronary occlusion and before reperfusion) or a low dose (0.15 mg.kg-1.min-1) of adenosine with or without lignocaine was infused for 60 min starting 5 min before the onset of reperfusion. Group 1 was untreated, while group 2 received a high dose of adenosine with lignocaine. These groups were reperfused for 3 h. Group 3 was untreated, group 4 received a low dose of adenosine, and group 5 a low dose of adenosine and lignocaine. These groups were reperfused for 72 h. EXPERIMENTAL MATERIAL--60 anaesthetised open chest rabbits were used. Groups 1 and 2 were killed after 3 h coronary reperfusion. Groups 3, 4, and 5 recovered from surgery for 72 h and were then killed for further study. MEASUREMENTS AND MAIN RESULTS--The high dose of adenosine reduced mean blood pressure to 44% of baseline value and diminished reactive hyperaemia in the area at risk by "coronary steal". The low dose of adenosine did not significantly alter systemic blood pressure or heart rate. Infarct size did not differ between groups 1 and 2, at 39.7(SD 20.1)% of area at risk v 33.2(15.9)% (by tetrazolium staining), nor between groups 3, 4, and 5: 50.3(12.6)% v 52.7(15.6)% v 47.8(9.3)% (by histology). CONCLUSION--Neither a high dose nor a low dose of adenosine limited myocardial infarct size in the rabbit heart even when adenosine was combined with lignocaine treatment.  相似文献   
9.
目的 采用TCGA数据挖掘和网络药理学方法分析小柴胡汤治疗肝细胞癌(HCC)的药效物质基础及药理机制.方法 通过TCGA数据库挖掘HCC差异表达基因、通过TCMID、TCMSP数据库和文献检索得到小柴胡汤的活性成分及其作用靶点;绘制韦恩图获得小柴胡汤-HCC共有靶点.通过Cytoscape软件构建疾病-药物-有效成分-...  相似文献   
10.
综合疗法治疗非动脉炎性前部缺血性视神经病变   总被引:3,自引:0,他引:3  
目的观察复方樟柳碱联合高压氧综合治疗非动脉炎性前部缺血性视神经病变(NAION)的疗效。方法采用随机方法将患者58例(64只眼)分入观察组30例和对照组28例。对照组采用局部注射激素,全身应用低分子右旋糖酐、复方丹参液、神经营养剂。观察组:除应用同对照组相同的药物外,予复方樟柳碱作患侧颞浅动脉旁皮下注射,配合高压氧综合治疗。以视力、视野、眼底改变为疗效判断指标。结果有效率治疗组为83.33%,对照组为53.57%,二者比较,差异有显著性意义(P<0.05)。结论复方樟柳碱联合高压氧综合疗法可提高非动脉炎性前部缺血性视神经病变的疗效。  相似文献   
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