全文获取类型
收费全文 | 9594篇 |
免费 | 592篇 |
国内免费 | 38篇 |
专业分类
耳鼻咽喉 | 113篇 |
儿科学 | 246篇 |
妇产科学 | 115篇 |
基础医学 | 1285篇 |
口腔科学 | 356篇 |
临床医学 | 755篇 |
内科学 | 2517篇 |
皮肤病学 | 370篇 |
神经病学 | 961篇 |
特种医学 | 247篇 |
外科学 | 1378篇 |
综合类 | 54篇 |
一般理论 | 4篇 |
预防医学 | 630篇 |
眼科学 | 239篇 |
药学 | 455篇 |
中国医学 | 21篇 |
肿瘤学 | 478篇 |
出版年
2024年 | 11篇 |
2023年 | 137篇 |
2022年 | 210篇 |
2021年 | 489篇 |
2020年 | 248篇 |
2019年 | 382篇 |
2018年 | 425篇 |
2017年 | 222篇 |
2016年 | 273篇 |
2015年 | 340篇 |
2014年 | 432篇 |
2013年 | 553篇 |
2012年 | 845篇 |
2011年 | 854篇 |
2010年 | 403篇 |
2009年 | 366篇 |
2008年 | 633篇 |
2007年 | 601篇 |
2006年 | 589篇 |
2005年 | 494篇 |
2004年 | 422篇 |
2003年 | 348篇 |
2002年 | 354篇 |
2001年 | 59篇 |
2000年 | 52篇 |
1999年 | 52篇 |
1998年 | 41篇 |
1997年 | 57篇 |
1996年 | 46篇 |
1995年 | 38篇 |
1994年 | 26篇 |
1993年 | 14篇 |
1992年 | 16篇 |
1991年 | 15篇 |
1990年 | 15篇 |
1989年 | 16篇 |
1988年 | 13篇 |
1987年 | 5篇 |
1986年 | 9篇 |
1985年 | 8篇 |
1984年 | 13篇 |
1982年 | 16篇 |
1981年 | 10篇 |
1980年 | 12篇 |
1977年 | 7篇 |
1976年 | 7篇 |
1975年 | 4篇 |
1974年 | 7篇 |
1973年 | 8篇 |
1962年 | 4篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
41.
C. Vilches J.-M. Garcia-Pacheco R. de Pablo S. Puente M. Kreisler 《Tissue antigens》1996,48(5):589-592
A novel HLA-DQB1 allele was detected by oligotyping in the Bubi population of Equatorial Guinea. In order to characterize the new allelic variant, a RT-PCR method which permitted the cloning of its complete coding region was designed. With this method, we have determined the nucleotide sequence of the new DQB1*0612 allele, related to *0604 and *0609 but differing from them at polymorphic codon 70. A proposal for the improvement of the sequencing strategies of HLA class II alleles is made. 相似文献
42.
43.
E. Estefanía N. Gmez‐Lozano R. De Pablo M. E. Moreno C. Vilches 《International journal of immunogenetics》2003,30(1):11-12
We have isolated the complete coding region of HLA‐B*39 from a Spanish Caucasoid, using a new PCR primer for its 5′ untranslated region. The cDNA matched partial genomic sequences of B*3924, an allele whose distribution appears to be restricted to Mediterranean and Arabian Caucasoids. A single amino acid change exclusive to B*3924 (threonine‐98) distinguishes it from B*3903. 相似文献
44.
Miranda D Puente J Blanco L Jara P Wolf ME Mosnaim AD 《Research communications in molecular pathology and pharmacology》2002,111(1-4):3-12
Peripheral blood mononuclear cell (PBMC) cytotoxicity against S. typhi (wild type or mutant strain TYT1231)-infected U937 cells was significantly higher than its lytic effect against noninfected cells (control) at the various effector-to-target cell ratio used (30:1, 50:1 and 70:1). Natural killer cell activity [expressed as % specific lysis (mean +/- SEM); 30:1 (25.4 +/- 3.6, 25.1 +/- 4.2 and 16.3 +/- 3.3); 50:1 (27.8 +/- 3.7, 26.7 +/- 4.5 and 20.9 +/- 2.9) and 70:1 ratio (33.2 +/- 5.9, 29.4 +/- 4.2 and 22.8 +/- 2.8), respectively] appeared to be dependent on such ratios and independent of the S strain studied. Most (80%) of individual samples tested showed at least a 20% specific lysis increase over their own control; essentially no changes or smaller increases in NKC activity were observed in all other samples. Similar results were obtained when using highly purified NKC (HPNKC) preparations as effector cells [NKC activity (mean +/- SEM); 5:1 (46.2 +/- 4.7, 43.2 +/- 5.0 and 25.2 +/- 2.3) and 10:1 effector-to-target cell ratio (49.3 +/- 4.9, 44.7 +/- 5.2 and 27.2 +/- 2.6, respectively)]. All individual samples tested showed at least a 20% specific lysis increase over their own control. These results show that S. typhi-infected U937 cells are a significantly better target for NKCs than control cells and indicate that intracellular bacteria survival capacity is not a critical factor for infected cells becoming a NKC target. 相似文献
45.
A new syndrome of triphalangeal thumbs and brachy-ectrodactyly 总被引:2,自引:0,他引:2
Alessandra Carnevale Maricela Hernández Victoria del Castillo Pablo Torres 《Clinical genetics》1980,18(4):244-252
Two Mexican families in which a total of 17 persons exhibited the same pattern of limb malformations are described. The syndrome is characterized by triphalangeal thumbs and brachydactyly affecting the index fingers and the third toes. The clinical findings are variable and the inheritance is autosomal dominant. The syndrome, to the best of our knowledge, has not been described before. 相似文献
46.
Occurrence and Potential Diagnostic Applications of Serological Cross-Reactivities between Brucella and Other Alpha-Proteobacteria 下载免费PDF全文
M. Victoria Delpino Carlos A. Fossati Pablo C. Baldi 《Clinical and Vaccine Immunology : CVI》2004,11(5):868-873
Agrobacterium, Sinorhizobium, and Ochrobactrum are genera closely related to Brucella but, in contrast to the latter, are not pathogenic for humans and animals. We studied by an indirect enzyme-linked immunosorbent assay (ELISA) the reactivities of brucellosis sera against cytosolic (CYT) and membrane (MA) antigens from these nonpathogenic bacteria, and we evaluated the potential usefulness of these cross-reactions for the diagnosis of brucellosis in humans, sheep, cows, and dogs. Canine infection by Brucella canis was detected with high specificity by CYT antigen-based ELISAs (96% for Agrobacterium, 96% for Sinorhizobium, and 91% for Ochrobactrum), while sensitivity was variable (58% for Agrobacterium, 88% for Sinorhizobium, and 84% for Ochrobactrum). In addition, it was possible to diagnose canine disease shortly after exposure to the pathogen (15 days). Similar results for canine brucellosis were obtained with MA antigens. In contrast, normal sera from humans, sheep, and cattle reacted strongly with all the antigens (CYT and MA antigens from the three bacteria), producing high cutoff values and, consequently, low sensitivities. While for some host species the reactivity patterns of normal sera by Western blotting were similar to those produced with sera from infected individuals, the reactivity pattern of bovine sera against Sinorhizobium meliloti antigens exhibited some differential bands for the two groups of sera. These results show that crude fractions from nonpathogenic alpha-proteobacteria can be used to diagnose canine brucellosis but may need to be further separated into simpler fractions to have diagnostic usefulness in ovine, bovine, or human infection. By reducing the biosafety requirements, the use of antigens derived from these nonpathogenic bacteria would simplify the production of diagnostic kits for brucellosis, especially in settings where biosafety level-3 facilities are scarce or absent. 相似文献
47.
Bellido I Gomez-Luque A Plaza A Rius F Ortiz P Sanchez de la Cuesta F 《Neuroscience letters》2002,321(1-2):110-114
S-adenosyl-L-methionine (SAM) has shown efficacy in speeding the onset of the antidepressant effect of imipramine in depressed patients. This effect may be related to their interactions at the serotonin(1A) (5-HT(1A)) receptors. Acute imipramine up-regulated the frontal cortex 5-HT(1A) receptors (B(max), 51.5 +/- 8.4 fmol/mg protein) vs. saline (B(max), 27.5 +/- 5.9 fmol/mg protein), and did not show antidepressant effect. Acute SAM and imipramine+SAM did not modify frontal cortex 5-HT(1A) receptors, and showed antidepressant effects (decrease of the immobility response of 26%, P<0.01; and 47%, P<0.001) vs. saline. All the chronic treatments showed antidepressant effects and up-regulated the hippocampus 5-HT(1A) receptors. SAM prevents the 5-HT(1A) receptor up-regulation induced by acute imipramine in the frontal cortex. This mechanism may contribute to imipramine's antidepressant effect. 相似文献
48.
The novel HLA-Cw*1802 allele is associated with B*5703 in the Bubi population from Equatorial Guinea
C. Vilches M. Bunce R. de Pablo M. E. Moreno S. Puente L. Sanz M. Kreisler 《Tissue antigens》1997,49(6):644-648
The HLA-Cw*1801 specificity, a Cw7/Cw4 hybrid allele, has recently been described in association with B*8101 (formerly B"DT"). In this study, the new Cw*1802 variant, differing from Cw*1801 at exon 5. is found associated with B*5703 in Bubi individuals from Equatorial Guinea. Confirmatory complete coding regions of B*5703 and B*3910 are also reported. 相似文献
49.
Albuisson J Pêcheux C Carel JC Lacombe D Leheup B Lapuzina P Bouchard P Legius E Matthijs G Wasniewska M Delpech M Young J Hardelin JP Dodé C 《Human mutation》2005,25(1):98-99
Kallmann syndrome (KAL) combines hypogonadotropic hypogonadism and anosmia. Hypogonadism is due to Gonadotropin Releasing Hormone (GnRH) deficiency and anosmia is related to hypoplasia of the olfactory bulbs. Occasional symptoms include renal agenesis, bimanual synkinesia, cleft lip palate, dental agenesis. KAL is genetically heterogeneous and two genes have so far been identified, namely KAL1 (Xp22.3) and FGFR1/KAL2 (8p12), which underlie the X chromosome‐linked form and an autosomal dominant form of the disease, respectively. We studied a cohort of 98 unrelated Caucasian KAL patients. We identified KAL1 mutations in 14 patients, of which 7 (c.3G>A (p.M1?), g.IVS1+1G>T, c.570_571insA (p.R191fsX14), c.784G>C (p.R262P), c.958G>T (p.E320X), c.1651_1654delinsAGCT (p.P551_E552delinsSX), c.1711T>A (p.W571R)) have not been previously reported. In addition, we found FGFR1 mutations in 7 patients, namely c.303G>A (p.V102I), C.385A>C (p.D129A), c.810G>A (p.V273M), c.1093_1094delAG (p.R365fsX41), c.1561G>A (p.A520T), c.1836_1837insT (p.Y613fsX42), c.2190C>G (p.Y730X), all of which were novel mutations. In this study, unilateral renal agenesis and bimanual synkinesia were exclusively found associated with KAL1mutations, cleft palate and dental agenesia with FGFR1mutations. © 2004 Wiley‐Liss, Inc. 相似文献
50.
Anthony J McGoron Michael Capille Michael F Georgiou Pablo Sanchez Juan Solano Manuel Gonzalez-Brito John W Kuluz 《BMC medical imaging》2008,8(1):4