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61.
Background: This study was conducted to investigate grading performance when estimating the severity of static versus dynamic images of contact lens‐related ocular pathology. Methods: Thirty‐eight subjects used the Efron Grading Scales for Contact Lens Complications to grade the severity of ocular pathological changes depicted in static and dynamic (movie clip) computer‐displayed images of each of the following contact lens complications: bulbar conjunctival redness, limbal redness, papillary conjunctivitis, corneal staining, corneal infiltrates and meibomian gland dysfunction. The viewing of static and dynamic images was separated by seven weeks. Results: Grades assigned to dynamic images were 0.6 and 0.7 grading scale units higher than those assigned to static images for limbal redness and papillary conjunctivitis, respectively (p < 0.0001 for both). No difference was observed for the other four complications. There was an apparent trend for grading variability to be reduced (that is, observers grading in closer agreement) when grading dynamic versus static images. Conclusions: Absolute grades based on an assessment of signs of pathology represented in static images may, in some instances, underestimate the true severity of the condition. 相似文献
62.
Leukemia clusters around nuclear facilities in Britain 总被引:1,自引:0,他引:1
Brian McMahon 《Cancer causes & control : CCC》1992,3(3):283-288
He bas been retained for the defense by British Nuclear Fuelsplc in two suits in which leukemia and non-Hodgkin's lymphoma have been alleged to result from radiation exposures due to the operation of the nuclear reprocessing plant at Sellafield. This paper has been sent to the senior authors of the papers reporting clusters of leukemia or other malignancy in the vicinity of nuclear facilities in Britain and their comments invited. Subject to considerations of space and CCC style, these comments will be published as submited. 相似文献
63.
测定27例肾腺癌的DNA含量,并联系肿瘤的分级等部分形态学指标,对透明细胞型和颗粒细胞型肿瘤进行比较分析。发现:透明细胞型肾腺癌的分化一般较好,DNA以二倍体为主,预后相对较好;而颗粒细胞型肾腺癌的分化较差,DNA以非二倍体为主,其预后较差。 相似文献
64.
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66.
The objective of this investigation was to demonstrate the possible interactions of systemic lidocaine (lido) with inhibitory receptors in the spinal cord. In the lumbar dorsal horn of anesthetized and curarized rats, 60 physiologically identified, wide dynamic range (WDR) neurons, were recorded extracellularly. Glutamate, glycine and its selective antagonist, strychnine, were iontophoretically applied onto the neurons either singularly or concurrently. The effects of systemic lido on the drug-induced frequency changes and the interaction with the glycine receptors, using strychnine as a probe, were studied. It was consistently found that (i) lido (3–4 mg/kg) inhibited the excitatory responses to iontophoretic glutamate, (ii) this inhibition was significantly antagonized by concurrent iontophoretic strychnine, (iii) iontophoretic glycine induced comparable glutamate inhibition that was reversed by strychnine. In contrast, no effect on glutamate-induced excitations was observed when lido was applied by micropressure or a different local anesthetic was systemically administered. The results suggest that central inhibitory effects of lido could by mediated by spinal strychnine-sensitive glycine receptors, activated by lido itself or possibly by its glycine residue-bearing metabolites. 相似文献
67.
腹主动脉瘤动脉壁血管平滑肌细胞增殖及凋亡的研究 总被引:3,自引:0,他引:3
目的研究腹主动脉瘤 (abdominalaorticaneurysm ,AAA)在发病不同时期动脉壁平滑肌细胞 (smoothmusclecells,SMC)增殖与凋亡的改变。方法建立大鼠AAA模型 ,分别于术后 3d、1、2、3、4周切取腹主动脉 ,应用原位DNA片段末端标记 (TUNEL)和免疫组织化学方法检测腹主动脉壁中SMC凋亡和相关基因bcl 2、bax蛋白以及增殖细胞核抗原 (PCNA)、α 血管平滑肌肌动蛋白(α actin)的表达。结果TUNEL及PCNA表达高峰时段分别为术后 2~ 3周和 1周 ;术后 3d至 1周凋亡细胞少于PCNA阳性SMC ,2~ 4周多于PCNA阳性SMC且SMC数量明显减少 ;bcl 2与bax蛋白表达分别于术后 1、3周达到峰值 (P <0 0 1)。结论动脉壁SMC增殖和凋亡的失衡与AAA发病密切相关 ;bcl 2与bax基因参与了对AAA动脉壁中SMC凋亡的调控。 相似文献
68.
目的:建立简便、灵敏的HBV DNA序列中BCP双突变点的检测方法.方法:采用终点终止法和偏振光检测技术进行点突变的检测.首先对HBV C区基因进行PCR扩增,然后用特异探针与扩增产物中待测核苷酸的下游序列杂交,使探针的3’端可以在DNA聚合酶的催化下,依据其互补链上的待测核苷酸连接上一个标有特定荧光素的ddNTP,然后检测该3’端带有荧光素的探针,根据检测到的荧光素种类和偏振光的强度可以判定待测点是何种核苷酸.结果:该方法可以检测出HBV基因序列中BCP双突变核苷酸类型以及检测1个拷贝的模板,并且可以从BCP野性株DNA序列中检出5%BCP双突变DNA序列.结论:该技术可以检测血清中HBV DNA C区BCP双突变. 相似文献
69.
连续核移植对异种山羊(Bore)克隆胚胎发育的影响 总被引:1,自引:0,他引:1
目的探讨连续核移植与异种山羊克隆胚胎发育之间的关系。方法分别以波尔(Bore)山羊耳部成纤维细胞、山羊-兔异种克隆桑椹胚卵裂球为核供体,以兔卵母细胞为受体,进行连续核移植。结果共构建145枚异种原代重构卵、73枚继Ⅰ代及20枚继II代重构卵,经电融合后,获得重构胚数分别为90、58和14枚,融合率分别为62.1%、79.5%和70%;162枚重构胚在同等条件下进行体外共培养,卵裂率分别为72.2%、75.9%和28.6%,囊胚率分别为10%、13.8%和0%;融合率方面,原代、继I及继II重构卵之间无显著差异(P>0.05);早期发育率无显著差异,但继Ⅰ代重构胚高于原代重构胚,相反,继II代远低于前两者,差异极显著(P<0.01)。结论波尔山羊体细胞核经第1次核移植过程中异种受体卵胞质作用后,比高度分化的体细胞更有利于重构胚的发育,但异种山羊克隆胚卵裂球反复多次暴露在异种卵胞质中,可能不利于细胞核的发育。 相似文献
70.
A restricted field of view (rFOV) approach for imaging a dynamic time series of volumes of limited spatial extent within a larger subject is described. The shorter readout with rFOV-MRI can be exploited to either limit image artifacts or increase spatial resolution. To accomplish rFOV imaging of a multislice volume for a dynamic series, an outer volume suppression (OVS) preparation that saturates signal external to a cylinder through the subject is followed by slice-selective excitation and a spiral readout. The pass- and stopband efficiencies of the OVS in an agar gel phantom were 97% (+/-1.5%) and 3% (+/-1%), respectively. Profiles of the temporal signal-to-noise ratio (SNR) were measured in a phantom and an adult brain. The rFOV sequence reduced distortions from off-resonance signal and T2*-induced blurring compared to a conventional sequence. Sequence utility is demonstrated for high-resolution rFOV functional MRI (fMRI) in the visual cortex. The rFOV sequence may prove to be useful for other multislice dynamic and high-resolution imaging applications. 相似文献