全文获取类型
收费全文 | 13180篇 |
免费 | 699篇 |
国内免费 | 95篇 |
专业分类
耳鼻咽喉 | 88篇 |
儿科学 | 225篇 |
妇产科学 | 123篇 |
基础医学 | 2134篇 |
口腔科学 | 97篇 |
临床医学 | 1344篇 |
内科学 | 2926篇 |
皮肤病学 | 356篇 |
神经病学 | 1295篇 |
特种医学 | 523篇 |
外科学 | 2019篇 |
综合类 | 48篇 |
一般理论 | 2篇 |
预防医学 | 656篇 |
眼科学 | 215篇 |
药学 | 919篇 |
中国医学 | 40篇 |
肿瘤学 | 964篇 |
出版年
2023年 | 63篇 |
2022年 | 84篇 |
2021年 | 255篇 |
2020年 | 151篇 |
2019年 | 224篇 |
2018年 | 316篇 |
2017年 | 201篇 |
2016年 | 236篇 |
2015年 | 268篇 |
2014年 | 371篇 |
2013年 | 510篇 |
2012年 | 902篇 |
2011年 | 1020篇 |
2010年 | 601篇 |
2009年 | 535篇 |
2008年 | 870篇 |
2007年 | 1009篇 |
2006年 | 904篇 |
2005年 | 943篇 |
2004年 | 876篇 |
2003年 | 859篇 |
2002年 | 837篇 |
2001年 | 133篇 |
2000年 | 98篇 |
1999年 | 141篇 |
1998年 | 212篇 |
1997年 | 163篇 |
1996年 | 160篇 |
1995年 | 109篇 |
1994年 | 109篇 |
1993年 | 108篇 |
1992年 | 92篇 |
1991年 | 54篇 |
1990年 | 45篇 |
1989年 | 57篇 |
1988年 | 44篇 |
1987年 | 39篇 |
1986年 | 41篇 |
1985年 | 27篇 |
1984年 | 43篇 |
1983年 | 37篇 |
1982年 | 41篇 |
1981年 | 31篇 |
1980年 | 34篇 |
1979年 | 22篇 |
1978年 | 19篇 |
1977年 | 16篇 |
1976年 | 10篇 |
1975年 | 8篇 |
1974年 | 12篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
81.
Dien Pham Huy Monique Roch-Arveiller Monique Lenoir Olivier Muntaner Alain Thuret Jean-Paul Giroud 《Inflammation research》1986,18(3-4):366-371
The effect of piroxicam on rat polymorphonuclear leucocytes (PMN) has been studiedin vitro andin vivo after the induction of two acute, non specific inflammatory reactions (pleurisies induced by calcium pyrophosphate crystals (CaPP) or isologous serum).An inhibition of chemotaxis by piroxicam has been demonstrated by two techniques, the filter and agarose assaysin vivo andin vitro. An inhibition of random cell migration has been observed only at the higher drug concentration using agarose assay with CaPP-elicited cells.Piroxicam also inhibited superoxide anion generation and O2 consumption of CaPP- and serum-elicited cells.These findings suggest that piroxicam may have a direct effect on PMN responses and that this activity could, at least in part, contribute to its anti-inflammatory properties. 相似文献
82.
Brémond-Gignac D Gérard-Blanluet M Copin H Bitoun P Baumann C Crolla JA Benzacken B Verloes A 《American journal of medical genetics. Part A》2005,134(4):422-425
The WAGR contiguous gene deletion syndrome is a combination of Wilms tumor, Aniridia, Genito-urinary abnormalities, and growth and mental retardation which is invariably associated with an 11p13 deletion. We report two monozygotic twins and a third, unrelated patient with WAGR syndrome and additional clinical features not usually associated with WAGR. Both twins had developmental delay, growth deficiency, severe ocular involvement (nystagmus, aniridia, cataracts), atrial septal defect and two uncommon findings: agenesis of the corpus callosum and duplication of the halluces. One twin developed Wilms tumors aged 19 months while her sister remained tumor free by the age of 6.5 years. The singleton patient showed typical WAGR syndrome and preaxial hallucal polydactyly. Molecular cytogenetic studies refined the identification of the extent of the deleted segments, which were not identical in the two families. The two deletions included the PAX6 and WT1 genes as previously reported in typical WAGR patients. The unusual anomalies described in this report, may represent the expression of low penetrant traits associated with haploinsufficency of one or more of the genes present in the deletion (PAX6 is expressed in CNS) or may indicate epistatic influences of modifier genes on the expression of gene(s) present in the WAGR region. 相似文献
83.
Batard T Didierlaurent A Chabre H Mothes N Bussières L Bohle B Couret MN Ball T Lemoine P Focks Tejkl M Chenal A Clément G Dupont F Valent P Krauth MT André C Valenta R Moingeon P 《International archives of allergy and immunology》2005,136(3):239-249
BACKGROUND: We describe the production in Escherichia coli as a recombinant protein of clinical grade wild-type Bet v 1a (rBet v 1a), to be used as a candidate vaccine against birch pollen allergy. METHODS: This recombinant protein was purified by hydrophobic interaction and ion exchange chromatography and characterized by SDS-PAGE, immunoprint and circular dichroism in parallel with natural Bet v 1 (nBet v 1) purified from a birch pollen extract. We also compared rBet v 1 and nBet v 1 for their capacity to induce histamine release from basophils and to stimulate T lymphocyte proliferation. RESULTS: rBet v 1a appears in SDS-PAGE as an 18-kDa monomeric protein, whereas purified nBet v 1 comprises a mixture of isoforms (resolving as three distinct bands and six spots after 1-dimensional and 2-dimensional electrophoresis, respectively). Both recombinant and natural purified Bet v 1 molecules are recognized by IgE from birch pollen-allergic patients as well as anti-Bet v 1 murine monoclonal antibodies, suggesting that the recombinant protein is correctly folded in a native configuration. Circular dichroism analysis confirmed that the two Bet v 1 molecules exhibit similar 3-dimensional structures, even if rBet v 1a appears more compact and stable in thermodenaturation/renaturation experiments. Both rBet v 1 and nBet v 1 induce the degranulation of sensitized basophils and proliferation of Bet v 1-specific T lymphocytes in a similar manner. CONCLUSIONS: On the basis of these structural and biological properties, rBet v 1a is a valid candidate vaccine against birch pollen allergy, currently evaluated in humans. 相似文献
84.
Blouquit S Sari A Lombet A D'herbomez M Naline E Matran R Chinet T 《American journal of respiratory cell and molecular biology》2003,29(2):245-251
Endothelin-1 (ET-1) exerts many biological effects in airways, including bronchoconstriction, airway mucus secretion, cell proliferation, and inflammation. We investigated the effect of ET-1 on Na absorption and Cl secretion in human bronchial epithelial cells. Addition of 10(-7) M ET-1 had no effect on the inhibition of the short circuit current (Isc) induced by amiloride, a Na channel blocker. Addition of 10(-7) M ET-1 to the apical bath in the presence of amiloride increased Isc in cultured human bronchial epithelial cells studied in Ussing chambers. No effect was observed when ET-1 was added to basolateral bath, indicating that the involved ET-1 receptors are likely present only in the apical membrane of the cells. Use of Cl-free solutions and bumetanide reduced the ET-1-induced increases in Isc, indicating that ET-1 stimulates Cl secretion. The ET-1-induced increase in Isc was prevented by exposure to the ETB receptor antagonist BQ-788 but not to the ETA receptor antagonist BQ-123. ET-1 did not raise intracellular Ca levels, but increased the intracellular concentration of cAMP. These findings indicate that ET-1 is a Cl secretagogue in human airways and acts presumably through apically located ETB receptors and activation of the cAMP pathway. 相似文献
85.
Morse MA Garst J Osada T Khan S Hobeika A Clay TM Valente N Shreeniwas R Sutton MA Delcayre A Hsu DH Le Pecq JB Lyerly HK 《Journal of translational medicine》2005,3(1):9-8
BACKGROUND: There is a continued need to develop more effective cancer immunotherapy strategies. Exosomes, cell-derived lipid vesicles that express high levels of a narrow spectrum of cell proteins represent a novel platform for delivering high levels of antigen in conjunction with costimulatory molecules. We performed this study to test the safety, feasibility and efficacy of autologous dendritic cell (DC)-derived exosomes (DEX) loaded with the MAGE tumor antigens in patients with non-small cell lung cancer (NSCLC). METHODS: This Phase I study enrolled HLA A2+ patients with pre-treated Stage IIIb (N = 4) and IV (N = 9) NSCLC with tumor expression of MAGE-A3 or A4. Patients underwent leukapheresis to generate DC from which DEX were produced and loaded with MAGE-A3, -A4, -A10, and MAGE-3DPO4 peptides. Patients received 4 doses of DEX at weekly intervals. RESULTS: Thirteen patients were enrolled and 9 completed therapy. Three formulations of DEX were evaluated; all were well tolerated with only grade 1-2 adverse events related to the use of DEX (injection site reactions (N = 8), flu like illness (N = 1), and peripheral arm pain (N = 1)). The time from the first dose of DEX until disease progression was 30 to 429+ days. Three patients had disease progression before the first DEX dose. Survival of patients after the first DEX dose was 52-665+ days. DTH reactivity against MAGE peptides was detected in 3/9 patients. Immune responses were detected in patients as follows: MAGE-specific T cell responses in 1/3, increased NK lytic activity in 2/4. CONCLUSION: Production of the DEX vaccine was feasible and DEX therapy was well tolerated in patients with advanced NSCLC. Some patients experienced long term stability of disease and activation of immune effectors. 相似文献
86.
Schindler I Rice NJ McIntosh RD Rossetti Y Vighetto A Milner AD 《Nature neuroscience》2004,7(7):779-784
When we reach out to pick something up, our arm is directed to the target by visuomotor networks in the cortical dorsal stream. However, our reach trajectories are influenced also by nontarget objects, which might be construed as potential obstacles. We tested two patients with bilateral dorsal-stream (parietal lesions, both of whom were impaired at pointing to visual stimuli (optic ataxia). We asked them to reach between two cylinders, which varied in location from trial to trial. We found that the patients' reaches remained invariant with changes in obstacle location. In a control task when they were asked to point midway between the two objects, however, their responses shifted in an orderly fashion. We conclude that the dorsal stream provides the visual guidance we automatically build into our movements to avoid potential obstacles, as well as that required to ensure arrival at the target. 相似文献
87.
Dr. M. Trudel F. Nadon C. Simard F. Bélanger R. Alain C. Séguin G. Lussier 《Archives of virology》1989,107(1-2):141-149
Summary A new continuous ovine kidney cell line allowing the growth of caprine, human and bovine respiratory syncytial virus was used to minimize host cell related variations for the direct comparison of the viral ultrastructures, serological relationships and structural protein profiles. Results show that all three strains are closely related although a closer relationship was found between bovine and caprine RS. 相似文献
88.
Multiscale structure of sheet nacre 总被引:20,自引:0,他引:20
Rousseau M Lopez E Stempflé P Brendlé M Franke L Guette A Naslain R Bourrat X 《Biomaterials》2005,26(31):6254-6262
This work was conducted on Pinctada maxima nacre (mother of pearl) in order to understand its multiscale ordering and the role of the organic matrix in its structure. Intermittent-contact atomic force microscopy with phase detection imaging reveals a nanostructure within the tablet. A continuous organic framework divides each tablet into nanograins. Their shape is supposed to be flat with a mean extension of 45nm. TEM performed in the darkfield mode evidences that at least part of the intracrystalline matrix is crystallized and responds like a 'single crystal'. The tablet is a 'hybrid composite'. The organic matrix is continuous. The mineral phase is thus finely divided still behaving as a single crystal. It is proposed that each tablet results from the coherent aggregation of nanograins keeping strictly the same crystallographic orientation thanks to a hetero-epitaxy mechanism. Finally, high-resolution TEM performed on bridges from one tablet to the next, in the overlying row, did not permit to evidence a mineral lattice but crystallized organic bridges. The same organic bridges were evidenced by SEM in the interlaminar sequence. 相似文献
89.
Chatelain D Devendeville A Rudelli A Bruniau A Geslin G Sevestre H 《Archives of pathology & laboratory medicine》2004,128(5):568-570
We report a case of gastric myeloid metaplasia in an 89- year-old woman with agnogenic myeloid metaplasia. The lesions were fortuitously discovered on upper endoscopy. The antral mucosa was thickened and polypoid, and on histologic examination contained immature granulocytes, megakaryocytes, and a few erythroblasts without desmoplastic stromal reaction. The granulocytes were positive for CD15, CD68, and myeloperoxidase on immunohistochemistry, and the megakaryocytes showed positive reactivity for factor VIII. Gastric myeloid metaplasia is a very rare event, and to our knowledge only 6 cases have been reported in the literature to date. It usually occurs in patients with advanced myeloproliferative syndrome. Gastric myeloid metaplasia often has a pseudotumoral appearance, leading to digestive symptoms. Histologic diagnosis is straightforward when trilinear hematopoietic elements are identified in gastric biopsies. Immunohistochemistry with anti-factor VIII antibody can be useful to confirm the presence of megakaryocytes. 相似文献
90.