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71.
72.
消炎痛对hCG诱发家兔排卵抑制的形态学研究 总被引:3,自引:0,他引:3
应用非甾体抗炎药消炎痛(20mg/kg)抑制hCG 诱发的家兔排卵,注射后的6、9、12、72小时剖腹观察排卵数,并取材进行透射电镜观察和酶组织化学观察。甾体激素合成酶类的组织化学和颗粒细胞内某些细胞器的电镜立体定量学测定结果表明:消炎痛抑制了排卵,却不影响颗粒细胞向黄体细胞的转变。透射电镜观察表明:在排卵前,实验组和对照组最明显的不同是:实验组的外膜和白膜很少见到胶原溶解现象,且表面上皮细胞内含的致密小体不释放其内容物。结果提示:消炎痛主要作用于排卵前卵泡顶部的成纤维细胞和表面上皮细胞,这可能与其抑制了某些与排卵有关的酶的释放有关。 相似文献
73.
The primordial plexiform neuropil is very critical to neocortical development. The pioneer neurons, mainly Cajal-Retzius cells
in the marginal zone, and subplate neurons in the subplate, differentiate from the primordial plexiform neuropil. In this
study, the development of corpus callosum, visual cortex, and subcortical pathways has been observed in C57BL/6 mice with
various methods, such as DiI labeling in vitro and in vivo, DiI and DiA in vitro double labeling, immunocytochemistry, and
in vivo BrdU and Fast Blue labeling. As early as E14, the primordial plexiform neuropil can be found in the telencephalic
wall, and it contains many pioneer neurons. On E15 the primordial plexiform neuropil differentiates into the marginal zone
and the subplate. Cajal-Retzius cells exist in the marginal zone, and subplate neurons are in the subplate. Either Cajal-Retzius
cells or subplate neurons have long projections toward the ganglionic eminence, suggesting that they migrate tangentially
from the ganglionic eminence. Cajal-Retzius cells are involved in radial migration, and subplate neurons participate to guide
pathfinding of subcortical pathways. This study reveals how the pioneer neurons, through radial and tangential migration,
play an important role in neocortical formation and in the pathfinding of the corpus callosum and subcortical pathways. Furthermore,
DiI labeling in vivo has demonstrated the presence of pioneer neurons all along the corpus callosum pathway, especially in
the midline. This suggests that pioneer neurons may also play a role in guiding the pathfinding of the corpus callosum.
Accepted: 31 July 2001 相似文献
74.
75.
Martineau M Jalali GR Barber KE Broadfield ZJ Cheung KL Lilleyman J Moorman AV Richards S Robinson HM Ross F Harrison CJ 《Genes, chromosomes & cancer》2005,43(1):54-71
This study was undertaken in order to compare the interphase and metaphase cytogenetics of 28 patients with ETV6/RUNX1 positive acute lymphoblastic leukemia, at diagnosis and relapse. The median time to relapse was 26 months. The significant fusion positive population heterogeneity revealed at interphase by a commercial probe for ETV6/RUNX1 fusion has not been described before. Six diagnostic samples had a single abnormal population; others had up to five each, which differed in the numbers of RUNX1 signals, and in the retention or loss of the second ETV6 signal. In contrast, the number of fusion signals was more constant. At relapse, there were fewer populations; the largest or unique clone was sometimes a re-emergence of a minor, diagnostic one, with a retained copy of ETV6 and the most RUNX1 signals. Abnormal, fusion negative clones were identified in bone marrow samples at extra-medullary relapse. Variant three or four-way translocations, which involved chromosomes 12 and 21, were prominent among the complex rearrangements revealed by metaphase FISH. The frequency of their occurrence at diagnosis and reappearance at relapse, sometimes accompanied by minor clonal evolution, was another new observation. Other recurrent cytogenetic features included a second copy of the fusion signal in six cases, partial duplication of the long arm of the X chromosome in two cases, and trisomy 10 in three cases. In comparing our data with previously reported cases, a picture is beginning to emerge of certain diagnostic features, which may provide circumstantial evidence of an increased risk of relapse. 相似文献
76.
探索采用血管透明化技术结合粒子图像测速技术(PIV)来研究搭桥血管内血流流场的可行性.结果显示血管透明化技术能完整地保留搭桥血管段在体内的真实立体几何构形,从而更准确地反应搭桥血管段在体内的血流流场,而PIV能很好地获得血流流场的信息.因此,将血管透明化技术与PIV相结合有可能使我们对旁路搭桥术后血管内膜增生的血流动力学成因进行更深入地研究. 相似文献
77.
Preparation and characterization of porous beta-tricalcium phosphate/collagen composites with an integrated structure 总被引:11,自引:0,他引:11
Porous beta-tricalcium phosphate (TCP)/collagen composites with different beta-TCP/collagen weight ratio were prepared. The influences of the preparation conditions on the microstructure of porous composite and the joint status of beta-TCP particles with collagen fibrils were characterized by X-ray diffractometer, scanning electron microscopy and transmission electron microscopy. The results showed: (1) an acid treatment could effectively disassemble collagen fibrils; (2) in the resulting porous composites, beta-TCP particles homogenously existed on the skeleton of the collagen fibril network and bonded tightly to both the fibrils and themselves. The tight bonding formation could be due to the reaction between Ca ions in the particles and carboxyl groups in collagen polypeptide chains and due to the reprecipitation of partially dissolved beta-TCP during synthesis. The tight bonding between beta-TCP particles and collagen fibrils in the composites demonstrated an integrated structure, which was reproducible when beta-TCP/collagen ratio ranged from 2 to 4. Such integrated structure would make significant contributions in reliably tailoring properties of the porous composites by varying beta-TCP content. In addition, the porous composites had large porosity (approximately 95%) and appropriate pore size (approximately 100 microm), showed no negative impact in cytotoxicity assay and complete bone tissue regeneration after 12 weeks in animal test. 相似文献
78.
用银染色法、免疫组织化学及透射电镜技术,对36例人肺的神经内分泌细胞进行了形态学和免疫组织化学观察。提示NE细胞发生了废用性退化,其原因可能与出生前后人肺功能改变有关。 相似文献
79.
Induction of protective immunity to monoclonal-antibody-defined Plasmodium falciparum antigens requires strong adjuvant in Aotus monkeys. 总被引:3,自引:4,他引:3
W A Siddiqui L Q Tam S C Kan K J Kramer S E Case K L Palmer K M Yamaga G S Hui 《Infection and immunity》1986,52(1):314-318
Monoclonal antibodies to the major Plasmodium falciparum merozoite surface coat and rhoptry antigens were produced. A combination of the affinity-purified polypeptides with Freund complete adjuvant which was given three times completely protected an Aotus lemurinus azure (karotype VI) monkey against homologous challenge; however, immunization with the same polypeptides with a muramyl dipeptide derivative [MDP-Lys(L18)] did not protect a second Aotus monkey, even though comparable high antibody titers were induced. 相似文献
80.
一种可生物降解温度敏感型聚乙二醇-聚己内酯-聚乙二醇水凝胶的合成和表征 总被引:1,自引:0,他引:1
合成了一系列分子量较低的聚乙二醇.聚己内酯-聚乙二醇(Poly(ethylene glycol)-Polycaprolactone-Poly(ethylene glycol),PEG-PCL—PEG)三嵌段共聚物。分别采用FTIR和1H—NMR对其结构进行了表征。所合成的PEG-PCL-PEG共聚物具有良好的水溶性,当水溶液浓度高于临界凝胶浓度(Critical gel concentration,CGC)时,随着温度的变化聚合物水溶液会呈现特有的凝胶-溶胶转变。研究了共聚物亲水疏水链段的比例和长度,以及热历史等对凝胶-溶胶转变行为的影响。通过调节上述条件,可以在一定程度上拓宽凝胶-溶胶转变温度范围,有助于PEG—PCL-PEG水凝胶在可注射药物控制释放系统等方面的应用。 相似文献