全文获取类型
收费全文 | 6897篇 |
免费 | 440篇 |
国内免费 | 34篇 |
专业分类
耳鼻咽喉 | 48篇 |
儿科学 | 175篇 |
妇产科学 | 137篇 |
基础医学 | 1009篇 |
口腔科学 | 139篇 |
临床医学 | 594篇 |
内科学 | 1662篇 |
皮肤病学 | 109篇 |
神经病学 | 710篇 |
特种医学 | 165篇 |
外科学 | 1165篇 |
综合类 | 44篇 |
一般理论 | 4篇 |
预防医学 | 459篇 |
眼科学 | 157篇 |
药学 | 378篇 |
中国医学 | 16篇 |
肿瘤学 | 400篇 |
出版年
2024年 | 20篇 |
2023年 | 65篇 |
2022年 | 108篇 |
2021年 | 216篇 |
2020年 | 140篇 |
2019年 | 199篇 |
2018年 | 182篇 |
2017年 | 152篇 |
2016年 | 173篇 |
2015年 | 186篇 |
2014年 | 278篇 |
2013年 | 372篇 |
2012年 | 476篇 |
2011年 | 540篇 |
2010年 | 262篇 |
2009年 | 238篇 |
2008年 | 393篇 |
2007年 | 437篇 |
2006年 | 394篇 |
2005年 | 377篇 |
2004年 | 370篇 |
2003年 | 334篇 |
2002年 | 312篇 |
2001年 | 44篇 |
2000年 | 32篇 |
1999年 | 46篇 |
1998年 | 37篇 |
1997年 | 44篇 |
1996年 | 35篇 |
1995年 | 31篇 |
1994年 | 27篇 |
1993年 | 23篇 |
1992年 | 24篇 |
1991年 | 33篇 |
1990年 | 27篇 |
1989年 | 20篇 |
1988年 | 23篇 |
1987年 | 21篇 |
1986年 | 25篇 |
1985年 | 20篇 |
1984年 | 29篇 |
1983年 | 23篇 |
1982年 | 32篇 |
1981年 | 32篇 |
1980年 | 19篇 |
1978年 | 18篇 |
1977年 | 15篇 |
1974年 | 19篇 |
1973年 | 15篇 |
1964年 | 15篇 |
排序方式: 共有7371条查询结果,搜索用时 0 毫秒
101.
102.
Neonatal exposure to monosodium glutamate induces morphological alterations in suprachiasmatic nucleus of adult rat 下载免费PDF全文
Julio César Rojas‐Castañeda Rosa María Vigueras‐Villaseñor Margarita Chávez‐Saldaña Patricia Rojas Oscar Gutiérrez‐Pérez Carolina Rojas Marcela Arteaga‐Silva 《International journal of experimental pathology》2016,97(1):18-26
Neonatal exposure to monosodium glutamate (MSG) induces circadian disorders in several physiological and behavioural processes regulated by the suprachiasmatic nucleus (SCN). The objective of this study was to evaluate the effects of neonatal exposure to MSG on locomotor activity, and on morphology, cellular density and expression of proteins, as evaluated by optical density (OD), of vasopressin (VP)‐, vasoactive intestinal polypeptide (VIP)‐ and glial fibrillary acidic protein (GFAP)‐immunoreactive cells in the SCN. Male Wistar rats were used: the MSG group was subcutaneously treated from 3 to 10 days of age with 3.5 mg/g/day. Locomotor activity was evaluated at 90 days of age using ‘open‐field’ test, and the brains were processed for immunohistochemical studies. MSG exposure induced a significant decrease in locomotor activity. VP‐ and VIP‐immunoreactive neuronal densities showed a significant decrease, while the somatic OD showed an increase. Major axes and somatic area were significantly increased in VIP neurons. The cellular and optical densities of GFAP‐immunoreactive sections of SCN were significantly increased. These results demonstrated that newborn exposure to MSG induced morphological alterations in SCN cells, an alteration that could be the basis for behavioural disorders observed in the animals. 相似文献
103.
Montserrat Plana Odette Vias Oscar de la Calle-Martin Francisco Lozano Julia Ingls-Esteve Matilde Romero Jos Alberola-Ila Jordi Yagüe Ramn Vilella Jordi Vives 《European journal of immunology》1991,21(4):1085-1088
The ability of the 134-2C2 monoclonal antibody (mAb; CD26) to transmit an activation signal and to affect T cell proliferation has been studied. The 134-2C2 mAb, although not being mitogenic by itself, is able to increase the proliferation of purified T cells in the presence of exogenous interleukin 2 (IL2) or phorbol 12-myristate 13-acetate (PMA). No effect of our mAb was observed on the proliferation of T cells induced by other stimuli such as Sepharose-bound CD3 mAb, phytohemagglutinin or calcium ionophore. Since the co-stimulatory effect of 134-2C2 mAb on PMA-induced T cell proliferation was strongly inhibited by an anti-Tac antibody, its involvement on the IL2/IL2 receptor pathway was investigated. An increased IL2 secretion in T cells cultured with PMA plus 134-2C2 mAb was observed and Northern blot analysis showed that the mAb 134-2C2 acts synergistically with PMA favoring the induction of both IL2 and interferon-γ mRNA synthesis, as well as the enhancement of IL2 receptor and transferrin receptor mRNA expression. Studies on mechanisms implicated in signal transduction showed that 134-2C2 mAb modifies neither intracellular calcium levels nor phosphoinositide breakdown. Additionally, no effect was exerted on protein kinase C translocation. These data suggest that the CD26 antigen is involved in T cell activation in an IL2/IL2 receptor-dependent pathway. 相似文献
104.
María E. Fraire María V. Sanchez-Vallecillo Mario E. Zernotti Oscar A. Paoletti 《Acta otorrinolaringologica espanola》2013,64(2):133-139
IntroductionChronic rhinosinusitis (CRS) is the inflammation of the nasal and paranasal sinus mucosa persisting for at least 12 weeks. The success of endoscopic sinus surgery (ESS) depends on minimising oedema and intraoperative bleeding. For this purpose, some surgeons advocate the use of preoperative systemic steroids (SS).Our aim was to assess if the administration of preoperative SS in patients with CRS with or without nasal polyps (NP) facilitates the surgical procedure.MethodsNon-randomized clinical trial in CRS patients with or without NP. Patients in the ESS group received oral meprednisone preoperatively, whereas the control group did not. The visibility of the surgical field, intraoperative bleeding and surgery duration were recorded.ResultsEach group (SS group and control group) included 27 patients. The administration of SS reduced the values of all the parameters in patients without NP, with no significant differences. In patients with NP, only operative bleeding was reduced significantly.ConclusionsEven though all the parameters decreased with the preoperative administration of SS, only operative bleeding was significantly reduced in patients with CRS with NP. 相似文献
105.
Conditioned Subjective Responses to Socially Relevant Stimuli in Social Anxiety Disorder and Subclinical Social Anxiety 下载免费PDF全文
106.
Mario Juarez‐Ortega Víctor G. Hernandez Patricia Arce‐Paredes Enrique B. Villanueva Miguel Aguilar‐Santelises Oscar Rojas‐Espinosa 《International journal of experimental pathology》2015,96(1):31-41
Leprosy is a disease consisting of a spectrum of clinical, bacteriological, histopathological and immunological manifestations. Tuberculoid leprosy is frequently recognized as the benign polar form of the disease, while lepromatous leprosy is regarded as the malignant form. The different forms of leprosy depend on the genetic and immunological characteristics of the patient and on the characteristics of the leprosy bacillus. The malignant manifestations of lepromatous leprosy result from the mycobacterial‐specific anergy that develops in this form of the disease. Using murine leprosy as a model of anergy in this study, we first induced the development of anergy to Mycobacterium lepraemurium (MLM) in mice and then attempted to reverse it by the administration of dialysable leucocyte extracts (DLE) prepared from healthy (HLT), BCG‐inoculated and MLM‐inoculated mice. Mice inoculated with either MLM or BCG developed a robust cell‐mediated immune response (CMI) that was temporary in the MLM‐inoculated group and long‐lasting in the BCG‐inoculated group. DLE were prepared from the spleens of MLM‐ and BCG‐inoculated mice at the peak of CMI. Independent MLM intradermally‐inoculated groups were treated every other day with HLT‐DLE, BCG‐DLE or MLM‐DLE, and the effect was documented for 98 days. DLE administered at a dose of 1.0 U (1 × 106 splenocytes) did not affect the evolution of leprosy, while DLE given at a dose of 0.1 U showed beneficial effects regardless of the DLE source. The dose but not the specificity of DLE was the determining factor for reversing anergy. 相似文献
107.
Pablo Ruiz Díaz Juan Mucci María Ana Meira Yanina Bogliotti Daniel Musikant María Susana Leguizamón Oscar Campetella 《Infection and immunity》2015,83(5):2099-2108
The trans-sialidases (TSs) from Trypanosoma cruzi, the agent of Chagas disease, are virulence factors shed to the bloodstream that induce strong alterations in the immune system. Here, we report that both enzymatically active TS (aTS) and its lectinlike isoform (iTS) disturb CD4 T cell physiology, inducing downregulation of Th1 cell functionality and in vivo cell expansion. By using ovalbumin-specific DO11.10 cells as tracers of clones developing the Th1 phenotype, we found that the infection induced significant amounts of gamma interferon (IFN-γ) but low levels of interleukin 2 (IL-2) and increased IL-4 production in vivo, in agreement with a mixed T helper response. The production of cytokines associated with the Th2 phenotype was prevented by passive transfer of anti-TS neutralizing antibodies. TSs also reduced the T cell receptor signaling as assayed by Zap-70 phosphorylation. TSs also reduced IL-2 and IFN-γ secretion, with a concomitant increase in IL-4 production and then an unbalancing of the CD4 T cell response toward the Th2 phenotype. This effect was prevented by using anti-IL-10 neutralizing antibodies or IL-10−/− antigen-presenting cells, supporting the subversion of this regulatory pathway. In support, TSs stimulated IL-10 secretion by antigen-presenting cells during their interaction with CD4 T cells. When polarized cells were stimulated in the presence of TSs, the secretion of IL-2 and IFN-γ was strongly downregulated in Th1 cells, while IL-2 production was upregulated in Th2 cells. Although the Th1 response is associated with host survival, it may simultaneously induce extensive damage to infected tissues. Thus, by delaying the elicitation of the Th1 response and limiting its effector properties, TSs restrain the cell response, supporting T. cruzi colonization and persistence while favoring host survival. 相似文献
108.
Television viewing time and risk of eating disorders in Spanish adolescents: AVENA and AFINOS studies 下载免费PDF全文
109.
Marcelo Dip Nora Cejas Guillermo Cervio Federico Villamil Viviana Tagliafichi Daniela Hansen Krogh Oscar Imventarza Carlos Soratti Liliana Bisigniano 《Pediatric transplantation》2015,19(1):56-61
In July 2005, Argentina switched from a categorical liver allocation system to a MELD/PELD‐based policy for patients with CLD. To analyze WL outcomes and survival after LT in children. From January 2000 to December 2010, 923 children were registered. Two consecutive five‐yr periods were analyzed and compared: Era I (January 2000–July 2005) (n = 379) and Era II (July 2005–December 31, 2010) (n = 544). All data were prospectively collected and analyzed using the Kaplan–Meier method. After adopting the MELD/PELD system, WL registrations increased by 44% (from 379 to 544) and the number of LT increased by only 24% (from 278 to 365). However, three‐month WL mortality rate (32% to 18%, p < 0.0001, HR 2.002 CI 95% 1.5–2.8) decreased significantly. No significant differences were observed between Era 1 and II in one‐yr post‐LT survival (77.5% vs. 84.1%, p = 0.3053) and in acute re‐LT rate (9% vs. 5%, p = 0.1746). Under the MELD/PELD‐based allocation system in Argentina, mortality on the WL significantly decreased in children with CLD without affecting post‐LT survival, although reduced access to LT was observed. 相似文献
110.
Bonny Patel Sasha Parets Matthew Akana Gregory Kellogg Michael Jansen Chihyu Chang Ying Cai Rebecca Fox Mohammad Niknazar Roman Shraga Colby Hunter Andrew Pollock Robert Wisotzkey Malgorzata Jaremko Alex Bisignano Oscar Puig 《Journal of assisted reproduction and genetics》2018,35(8):1489-1496