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31.
32.
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
33.
34.
Polycythemia vera (PV) is a clonal disease of the hematopoietic stem cell characterized by a hyperplasia of marrow erythropoiesis, granulocytopoiesis, and megakaryocytopoiesis. We previously reported that highly purified PV blood burst-forming units-erythroid (BFU-E) are hypersensitive to recombinant human interleukin-3 (rIL-3). Because these cells may be only a subset, and not representative of marrow progenitors, we have now studied partially purified marrow hematopoietic progenitor cells. Dose-response experiments with PV marrow BFU-E showed a 38-fold increase in sensitivity to rIL-3 and a 4.3-fold increase in sensitivity to recombinant human erythropoietin (rEpo) compared with normal marrow BFU-E. In addition, PV marrow colony-forming units-granulocyte-macrophage (CFU-GM) and CFU-megakaryocyte (CFU-MK) also showed a marked hypersensitivity to rIL-3 and to human recombinant granulocyte-macrophage colony-stimulating factor (rGM-CSF). Dose-response curves with rGM-CSF and blood BFU-E showed a 48-fold increase in sensitivity. No effect of rIL-4, rIL-6, human recombinant granulocyte-CSF (rG-CSF), or macrophage-CSF (rM-CSF) was evident, nor was there any effect of PV cell-conditioned medium on normal BFU-E, when compared with normal cell-conditioned medium. Autoradiography with 125I-rEpo showed an increase in Epo receptors after maturation of PV BFU-E to CFU-E similar to that shown with normal BFU-E, but no increase of specific binding of 125I-rIL-3 by PV CD34+ cells was seen compared with normal CD34+ cells. These studies show that PV marrow hematopoietic progenitor cells are hypersensitive to rIL-3 and rGM-CSF, similar to PV blood BFU-E. While the mechanism does not appear to be due to enhanced binding of rIL-3, the hypersensitivity of PV progenitor cells to IL-3 and GM-CSF may be a key factor in the pathogenesis of PV. 相似文献
35.
豚鼠中耳(听泡)内滴入0.5%、1%、2%环丙沙星与庆大霉素滴耳液7天或21天,借助光镜和扫描电镜观察内耳的显微和超微结构变化。结果证明环丙沙星对内耳没有明显的毒性作用。庆大霉素则使耳蜗明显受损,以底回为重,Corti’s器外毛细胞坏死较多,内毛细胞及支持细胞病变较轻。位觉斑耳石脱落,毛细胞纤毛粘连、脱落。壶腹嵴中央区纤毛也缺失。本实验对客观评价环丙沙星对内耳的作用及临床使用提供了形态学资料。 相似文献
36.
37.
研究了77例长沙地区孕、产妇的宫颈排毒(CMV)情况及母、婴的免疫状态,并对宫颈排毒及CMV一IgM阳性的母亲所生小孩进行临床追踪。结果显示:孕妇宫颈排毒率为4.5%,抗CMV-IgG和抗CMV-IgM阳性率分别为77%和13%,59例脐血CMV-IgM阴性。宫颈排毒的3例其抗体检测抗CMV-IgG均阳性,抗CMV-IgM仅一例阳性。作者认为,对妊娠期活动性CMV感染的诊断,仅检测抗CMV-IgG和抗CMV-IgM抗体滴度仍不足,尚须结合病毒分离和其它检测手段。 相似文献
38.
弥漫性轴索损伤(diffuse axonal injury,DAI)是以胼胝体、脑十等中线部位局灶性病变及脑白质广泛性轴索损伤为主,以原发昏迷时间长而又缺乏神经定位体征为其临床特征的一组原发性弥散性脑损伤。在重型颅脑损伤中占20%,病死率高达42%~62%。最常见于车祸颅脑损伤病人,也可见于高处坠落伤者。病人多合并其他部位损伤,特点为伤情重、变化快、并发症和休克发生率高,且病死率高。护理时矛盾多,易顾此失彼,影响临床治疗效果。为更好地总结对该类损伤病人的救治, 相似文献
39.
观测了100例成年尸体胃底、贲门及食管区静脉。结果显示:胃左、右静脉的出现率是96%和92%,胃小弯侧的静脉分布可归纳为5型:胃左静脉型、胃右静脉型、胃左静脉优势型、胃右静脉优势型和胃左右静脉均衡型。胃后静脉出现率为73.6%,胃左静脉与左膈下静脉间有相对恒定的吻合,此种情况占48%。在此基础上作者于1976年3月至1992年3月对52例因门脉高压症大出血患者行经胸门奇静脉断流术,急症手术死亡率为4.9%,急症手术止血率为92.6%,远期再出血率为11.4%。作者认为彻底断流的关键是识别胃小弯侧静脉分型、胃左静脉汇入部位及属支变化;胃后静脉及门腔吻合。阐述了经胸门奇静脉断流的优越性。 相似文献
40.
黄疸出血群赖型017株钩端螺旋体外膜单克隆抗体免疫... 总被引:3,自引:3,他引:0
BALB/c mice were immunized intraperitoneally with outer envelopes of serogroup icterohaemorrhagiae lai serovar strain 017 leptospires. Monoclonal antibodies against outer envelopes (IgG, agglutinating titre 1:25,600) were produced by hybridoma technique. The monoclonal antibodies ascites (diluted 1:100) 1 ml administered intraperitoneally 1 hour before the intraperitoneal injection of 2 x 10(8) leptospires of strain 017 and the subsequent daily administration of McAb in similar doses for five days protected 80% of guinea pigs. Survival rates of three control groups which received physiological saline, ascites of BALB/c mouse myeloma cell lines SP2/0, and monoclonal antibodies against Pseudomonas aeruginosa in place of monoclonal antibodies against outer envelopes of strain 017 leptospires were 10%, 20% and 10% respectively. When killed 20 days after challenge, guinea pigs of experiment group were normal at autopsy. Old pulmonary haemorrhage were present in the animals of three control groups. Passive immunoprotection experiments have demonstrated immunoprotection of monoclonal antibodies against outer envelopes of strain 017 leptospires. It will be valuable for separating protective antigen fraction of outer envelopes and studying new vaccine of leptospira. 相似文献