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971.
Effect on peripheral nerve vivo with human insulin-like regeneration by transgene in growth factor-1
BACKGROUND: Human insulin-like growth factor (hIGF-1) has been successful in treating peripheral nerve injury, but it is still unclear whether hIGF-1 after transgene in vivo has the effect on promoting the regeneration of peripheral nerve.
OBJECTIVE: To observe the effect of hIGF-1 on the regeneration of peripheral nerve by transgene in vivo with electrophysiology, histological morphology and ultromicro morphology.
DESIGN: A univariate design.
SETTINGS: Jilin Institute of Surgery, China-Japan Friendship Hospital Affiliated to Jilin University; School of Basic Medical Sciences, Jilin University.
MATERIALS: Thirty male adult Wistar rats of grade Ⅱ, weighing 200-250 g, were provided by the Animal Experimental Center of Jilin University [certification number: SCXK-(Ji)20030001]. The rats were raised in the environment at the temperature of 25 ℃ and humidity of 70%. All the rats were randomly divided into hIGF-1-treated group, treatment control group and blank control group, 10 rats in each group. Positive liposomes (mass concentration of 2 g/L) and pcDNA3.1 (mass concentration of 1 g/L) were purchased from Beijing Yuanpinghao Company; pcDNAhIGF-1 (mass concentration of 1 g/L) was provided by Dr. Shen from the School of Public Health of Jilin University. The liposomes were mixed with plasmids with the mass ratio of 1.5 to 10.Operative microscope was made by Jiangsu Zhenjiang Microsurgical Instrument Factory; EMB-5304K electromyogram (EMG) evoked potential meter by Nihon Kohden Corporation. HPIAS-1 000 high-acuity color pathological imaging analytical system (Japan) and JEM-1200EX transmission electron microscope (Japan) were also used.
METHODS: The experiments were carried out in Jilin Institute of Surgery from April to June in 2004. ① All the rats were anesthetized, and the right sciatic nerve was exposed, and it was clipped with a clip at 5 mm below the piriform muscle for 3 times, 10 s for each time. The pressed width was 3 mm, and formed as membrane under operating microscope (×6). Rats in the hIGF-1-treated group were subepineurially injected with the mixture of pcDNAhIGF-1 and positive liposomes (10 μL) immediately, those in the treatment control group were injected with the mixture of pcDNA3.1, positive liposomes and distilled water (10 μL), and those in the blank control group were not given any injection. ② The sciatic nerve functional indexes (SFI) were measured within 56 days postoperatively according to the methods used by Shen et al. ISFI=0 was taken as normal, and ISFI=-100 as completely damaged. EMG evoked potential meter was used to record the electrophysiological changes of the regenerated nerve fibers. The indexes of histological morphology in 5 randomly selected sights were determined with the color pathological imaging analytical system, and the ultrostructures of the regenerated nerve fibers were also observed.
MAIN OUTCOME MEASURES: ① Comparison of the SFI within 56 days postoperatively; ② Comparison of the electrophysiology, histological morphology and ultrastructure of the regenerated nerve fibers 56 days postoperatively.
RESULTS: All the 30 Wistar rats were involved in the analysis of results. ① SFI: The SFI values were gradually increased as time prolonged in all the three groups, and the changes were more obvious after 24 days, the SFI values recovered better at each time point in the hIGF-1-treated group than in the other two groups. ② Eelectrophysiological results of right sciatic nerve: The latency of motor evoked potential (MEP) was close between the treatment control group and the blank control group [(2.55±0.36), (2.65±0.55) ms, P > 0.05], but higher in the hIGF-1-treated group [(2.14±0.22) ms] than in the blank control group (P < 0.01). The amplitude and conduction velocity of MEP in the treatment control group [(6.67±0.69) mV, (29.57±4.06) m/s] were close to those in the blank control group [(6.60±0.59) mV, (29.22±3.20) m/s, P > 0.05], but those in the hIGF-1-treated group [(7.81±0.84) mV, (36.91±4.37) m/s] were larger or faster than those in the blank control group (P < 0.01). ③ Results of the pathological image analysis of the regenerated nerve fibers: The axonal diameter, thickness of myelin sheath of the regenerated nerve fiber and the number of myelinated nerve fiber in the treatment control group [(2.28±0.33) μm, (1.08±0.18) μm2, (71.80±8.25) fibers] were close to those in the blank control group [(2.18±0.29) μm, (1.03±0.15) μm2, (68.60±8.55) fibers] (P > 0.05), and those in the hIGF-1-treated group [(3.03±0.35) μm, (1.65±0.24) μm2, (88.20±8.82) fibers] were obviously larger or more than those in the blank control group (P < 0.01). ④ Ultrastructure of the regenerated nerve fibers of sciatic nerve: In the hIGF-1-treated group, the regenerated fibers of sciatic nerve were more and mature, manifested by thicker nerve fibers, thicker and evener myelin sheath, which were better than those in the other two groups.
CONCLUSION: The results of the quantitative parameters of the electrophysiology, gross histological morphology and ultrostructural changes in the process of repairing damaged peripheral nerve indicate that transgene in vivo with hIGF-1 can promote the neural regeneration after peripheral nerve injury. 相似文献
972.
缺氧诱导因子-1α在胶质瘤中的研究进展 总被引:2,自引:1,他引:1
缺氧诱导因子1(Hypoxiainduciblefactor1,HIF1)是调节细胞缺氧反应的主要转录因子,HIF1α为其活性调节亚单位。HIF1α在胶质瘤中表达显著增加,并与胶质瘤的恶性进展密切相关。HIF1为异二聚体结构,调控多种与细胞缺氧反应相关基因的表达;氧水平、相关癌基因与抑癌基因及细胞因子等均可调节HIF1α蛋白的表达;HIF1α和肿瘤内新生血管形成、细胞代谢、细胞凋亡及细胞坏死之间均存在密切关系,并可影响放化疗对肿瘤的疗效;以HIF1α为靶点的药物或基因治疗正在成为胶质瘤基础和临床研究关注的热点。 相似文献
973.
破骨细胞起源于骨髓的多潜能干细胞,破骨细胞的数量和功能决定了关节破坏与骨丢失的严重程度,而炎症本身并不介导关节破坏和骨丢失。炎症性关节的滑膜成纤维细胞产生大量的炎症因子,如肿瘤坏死因子-α(TNF-α)和白介素-1(IL-1)。这些炎症因子不仅诱发炎症反应,而且通过促进核因子κB受体激活子配体,间接或直接增加破骨细胞的生成,并促进其功能,从而将炎症反应与局部骨丢失及损坏联系在一起。本文综述了近年来关于TNF-α、IL-1及破骨细胞靶疗法在破骨细胞介导的炎症性骨丢失过程中的研究进展。TNF-α通过促进外周血破骨细胞前体细胞的分化直接影响关节局部成熟破骨细胞的最终数目,而IL-1主要通过延长成骨细胞的寿命及调控破骨细胞骨架的重组来增加其骨吸收能力。抑制破骨细胞生长及功能的破骨细胞靶疗法在治疗炎症性骨丢失和关节损伤等方面日益得到重视。 相似文献
974.
探讨肝硬化门脉高压病人的预后具有重要的临床意义。研究表明,不同病因预后各异,出现腹水后预后较差;根据静脉曲张程度、范围、压力及粘膜色泽可预测出血或再出血;门脉压力、肝脏血流及肝脏组织学改变与预后密切相关,血清 TSB、白蛋白、PT、胆酸、FN 和 LPS 等是较好的肝功能预后指环;肝功能的分级和判别模型的建立最有预测预后的价值。 相似文献
975.
应用细胞外微电极技术,观察和记录了Pf痛反应神经元对伤害性夹尾、伤害性电刺激坐骨神经和检验性刺激及脑内微量注射吗啡前后电活动变化的情况。在67只Wistar大鼠右侧Pf内记录了309个痛反应神经元,其中PI-EN64个,占神经元总数的20.71%。PI-EN对伤害性夹尾和电刺激坐骨神经均发生特异性的抑制-兴奋反应,对非伤害性刺激则不发生反应。伤害性刺激诱发放电之前有 相似文献
976.
977.
血小板体内聚集可使心肌微循环功能产生障碍,导致心律失常或心肌梗塞,血小板聚集在心脑血管疾病的发病机理中起着重要作用,因而对抗血小板聚集药物的研究日益引起人们 相似文献
978.
979.
本文研究了26株P_c~r或O_x~r金黄色葡萄球菌的细胞结合青霉素酶。证实它们除有细胞外青霉素酶还具有细胞结合青霉素酶。金黄色葡萄球菌的总青霉素酶活力为22947~387743u/ml。细胞外青霉素酶活力为140~2130u/ml,占总酶含量的1%以下(菌株85051例外);大量青霉素酶是细胞结合的青霉素酶,活力为19937~382033u/ml。 相似文献
980.
本实验以定量细胞化学的方法对种60Coy射线8Gy全身-次照射后第6天小鼠腹腔巨噬细胞的变化和5-羟色胺(5-HT)的辐射防护作用进行了观察.发现照射后第6天巨噬细胞吞噬消化鸡红细胞的能力明显低于对照组(P相似文献