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991.
Preparation,characterization, and DNA interaction studies of cationic europium luminescent copolymer
This paper proposed a simple synthetic strategy towards a novel cationic europium luminescent copolymer, poly(METAC-co-NIPAm-co-Eu(AA)3Phen) (PMNEu), and investigation about their complexation ability with DNA. In this approach, first, Eu(AA)3Phen complex monomer containing Eu3+, acrylic acid (AA), and 1,10-phenanthroline (Phen) was synthesized, and subsequently, free radical copolymerization of Eu(AA)3Phen complex monomer with other two functional monomers, [2-(methacryloyloxy) ethyl] trimethylammonium chloride (METAC) and N-isopropylarylamide (NIPAm), was carried out in methanol using azodiisobutyronitrile (AIBN) as the initiator. 1HNMR, GPC, fluorescence spectroscopy, UV–vis spectroscopy, and TEM were used to investigate the chemical structures, molecular weight and molecular weight distribution, fluorescence properties, UV spectra, and morphologies of PMNEu copolymer, respectively. Furthermore, the interaction of PMNEu with DNA was also studied with fluorescence spectroscopy, UV–vis spectroscopy, and agarose gel electrophoresis. These results indicated that PMNEu could interact with DNA via an electrostatic bonding mode and the bonding constant was 2.2 × 105 L/mol. Additionally, TEM observation showed that pure PMNEu formed micelles in water solution, while the size-controllable aggregations of PMNEu with DNA were obtained when PMNEu was mixed with DNA at various concentration ratios. A good biocompability of PMNEu was demonstrated through in vitro cytotoxicity assays. 相似文献
992.
《Journal of neurogenetics》2013,27(4):188-194
AbstractMigraine without aura (MWO) is the most common among migraine group, and is mainly associated with genetic, physical and chemical factors, and hormonal changes. We aimed to identify novel non-synonymous mutations predisposing to the susceptibility to MWO in a Chinese sample using exome sequencing. Four patients with MWO from a family and four non-migraine subjects unrelated with these patients were genotyped using whole-exome sequencing. Bioinformatics analysis was used to screen possible susceptibility gene mutations, which were then verified by PCR. In four patients with MWO, six novel rare non-synonymous mutations were observed, including EDA2R (G170A), UBE2NL (T266G), GBP2 (A907G), EMR1 (C264G), CLCNKB (A1225G), and ARHGAP28 (C413G). It is worth stressing that GBP2 (A907G) was absent in any control subject. Multiple genes predispose to the susceptibility to MWO. ARHGAP28-, EMR1-, and GBP2-encoded proteins may affect angiokinesis, which supports vasogenic theory for the etiological hypothesis of this disease. CLCNKB-encoded protein may affect cell membrane potential, which is consistent with the cortical spreading depression theory. UBE2NL-encoded protein may regulate cellular responses to 5-hydroxytryptamine, which is in accordance with trigeminovascular reflex theory. EDA2R and UBE2NL are located on the X chromosome, which supports that this disease may have gender differences in genetic predisposition. Replication in larger sample size would significantly strengthen these findings. 相似文献
993.
背景 胎儿鼻骨发育情况评估作为常规产前超声检查项目,是胎儿染色体检查的重要指标,近几年染色体微阵列分析技术(CMA)的应用使得产前胎儿染色体疾病的检查范围更广、准确度更高,在此基础上有必要对鼻骨发育异常和染色体异常之间的相关性重新进行总结,为临床提供参考。目的 探讨胎儿鼻骨发育异常或与其他产前筛查高危因素结合在预测胎儿染色体异常中的价值,以及CMA在胎儿鼻骨发育异常遗传学检测中的应用价值。方法 选取2016年12月-2020年1月于内蒙古自治区妇幼保健院进行产前超声检查并提示胎儿鼻骨缺失或发育不良的92例孕妇及胎儿为研究对象。收集其产检信息、遗传学检测结果及妊娠结局。遗传学检测方法包括染色体核型分析和CMA。结果 染色体核型分析检出染色体异常19例(20.7%),均为21-三体;CMA检出染色体异常25例(27.2%),包括21-三体19例,染色体微缺失微重复6例。孤立性与非孤立性鼻骨发育异常胎儿染色体异常发生率比较,差异无统计学意义(P>0.05)。与单纯孤立性鼻骨发育异常胎儿相比,孤立性鼻骨发育异常+颈项透明层(NT)增厚、孤立性鼻骨发育异常+血清学筛查(MSS)高风险、孤立性鼻骨发育异常+无创产前筛查(NIPT)高风险、孤立性鼻骨发育异常+2种及以上产前筛查高危因素胎儿染色体异常发生率均升高(P<0.05)。结论 鼻骨缺失或发育不良的胎儿染色体异常发生率较高,且与基因组变异有关;染色体核型分析、CMA结合其他产前筛查高危因素将有效提高染色体异常的检出率。CMA的应用为产前诊断提供了更多的染色体变异信息,建议所有类型的胎儿鼻骨缺失或发育不良进行染色体核型分析与CMA结合的遗传学检测。 相似文献
994.
995.
Ben Davidson 《Expert review of molecular diagnostics》2016,16(5):569-578
Ovarian cancer, consisting mainly of ovarian carcinoma, is the most lethal gynecologic malignancy. Improvements in outcome for patients with advanced-stage disease are limited by intrinsic and acquired chemoresistance and by tumor heterogeneity at different anatomic sites and along disease progression. Molecules and cellular pathways mediating chemoresistance appear to be different for the different histological types of ovarian carcinoma, with most recent research focusing on serous and clear cell carcinoma. This review discusses recent data implicating various biomarkers in chemoresistance in this cancer, with focus on studies in which clinical specimens have been central. 相似文献
996.
997.
998.
《Journal of biomaterials science. Polymer edition》2013,24(1-3):379-387
An improved strategy has been developed for detection of DNA sequence by using water-soluble cationic conjugated polymer (PFP)/single-strand (ss) DNA and peptide nucleic acid labeled with fluorescent dye (PNAC*), where an anionic surfactant (sodium dodecyl sulphate, SDS) system has been used to improve the sensitivity of the sensor. The method of detection is simple to use, fast and cost-effective. This method uses the phenomenon of Forester Resonance Energy Transfer (FRET). The detection sensitivity of the biosensor has been improved by about ten times by using the anionic surfactant. It is observed that the effect of surfactant is to increase the photoluminescence (PL) intensity of the PNAC* when the sequence of the DNA is complementary (to that of PNA probe). On the other hand when the two sequences are non-complementary, the PL intensity of the PNAC* is further reduced as compared to the case when surfactant was absent. 相似文献
999.
《Journal of chemotherapy (Florence, Italy)》2013,25(2):238-245
AbstractColeon C (6,11,12,14,16-pentahydroxyabieta-5,8,11,13-tetraen-7-one), extracted from Coleus forskohlii Briq., was investigated for its anti-tumor activity on eight human tumor cell lines (95-D, A375, HeLa, A431, MKN45, BEL7402, LoVo and HL60) and two normal ones (293, L02) by MTT and colony-forming assay in vitro. The results indicated that A375 was the most sensitive of all the cell lines. Hoechst 33258 staining showed fragmentation and condensation of chromatin. DNA ladder assay indicated the fragments of DNA because of apoptosis. Flow cytometric analysis demonstrated hypodiploid cells existed in A375 after Coleon C treatment. In the acute toxicity studies of C57BL/6 mice, LD50 of Coleon C was 1496±150 mg/kg. In the model of Lewis lung carcinoma, the average tumor weight in groups injected with 80 mg/kg Coleon C decreased by 48.9±14.3% compared with that of the control. These results indicate that Coleon C could effectively inhibit tumor cell proliferation and growth by inducing apoptosis with low toxicity. To our knowledge, this is the first report on the anti-tumor activity of Coleon C both in vitro and in vivo. 相似文献
1000.
Steffen Eickhardt Peter Braendstrup Erik Clasen‐Linde Karl E. Jensen Morten Alhede Thomas Bjarnsholt Niels Høiby Lars Vindeløv Claus Moser 《APMIS : acta pathologica, microbiologica, et immunologica Scandinavica》2013,121(5):456-459
Post‐transplant infections in allogeneic haematopoietic cell transplant (allo‐HCT) recipients often have severe consequences. This is especially the case when dealing with zygomycete infections where the result is often fatal. A major problem when dealing with zygomycete infections is the need for an accurate and fast diagnosis as the phylum is highly resistant towards the conventional antifungals. We herein describe a non‐fatal case of Lichtheimia corymbifera infection in an allo‐HCT recipient. 相似文献