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排序方式: 共有10000条查询结果,搜索用时 15 毫秒
61.
Tadech Boonpiyathad Willem van de Veen Oliver Wirz Milena Sokolowska Beate Rückert Ge Tan Atik Sangasapaviliya Panitan Pradubpongsa Rattanaporn Fuengthong Pattarawat Thantiworasit Sunee Sirivichayakul Kiat Ruxrungtham Cezmi A. Akdis Mübeccel Akdis 《The Journal of allergy and clinical immunology》2019,143(3):1077-1086.e10
62.
Adoptive transfer of CD4+ T cells into scid mice leads to a chronic colitis in the recipients. The transferred CD4+ T cells accumulate in the intestinal lamina propria (LP), express an activated Th1 phenotype and proliferate vigorously when exposed ex vivo to enteric bacterial antigens. As LP CD4+ T cells from normal BALB/c mice do not respond to enteric bacterial antigens, we have investigated whether colonic LP-derived CD4+ T cells from normal mice suppress the antibacterial response of CD4+ T cells from scid mice with colitis. LP-derived CD4+ T cells cocultured with bone marrow-derived dendritic cells effectively suppress the antibacterial proliferative response of CD4+ T cells from scid mice with colitis. The majority of these LP T-reg cells display a nonactivated phenotype and suppression is independent of antigen exposure, is partly mediated by soluble factor(s) different from IL-10 and TGF-beta, and is not prevented by the addition of high doses of IL-2 to the assay culture. Functionally and phenotypically the T-reg cells of the present study differ from previously described subsets of T-reg cells. The presence of T cells with a regulatory potential in the normal colonic mucosa suggests a role for these cells in the maintenance of local immune homeostasis of the gut. 相似文献
63.
One cDNA clone was purified from an adult Clonorchis sinensis cDNA library, and its deduced polypeptide sequence was found to be homologous with myosin regulatory light chain (MRLC) of invertebrates and vertebrates. Two amino-acid residues, Thr and Ser, were conserved at the phosphorylation sites that regulate the function of MRLCs. Recombinant C. sinensis MRLC (rCsMRLC) protein was produced and purified from Escherichia coli, and mouse anti-CsMRLC immune sera recognized a protein of molecular weight 24 kDa from a soluble protein preparation of C. sinensis. The CsMRLC protein was immunohistochemically localized to the muscle fibers of the subtegumental muscle layer and to the muscles of oral and ventral suckers. However, the rCsMRLC protein proved to be less useful antigen for the serodiagnosis of human clonorchiasis.The nucleotide sequence reported herein was submitted to GenBank and assigned accession number AY519356. 相似文献
64.
Hanisah Sharif Swati Acharya Gopal Krishna R. Dhondalay Gilda Varricchi Shoshanna Krasner-Macleod Wannada Laisuan Amy Switzer Madison Lenormand Elena Kashe Rebecca V. Parkin Yi Yi Merve Koc Oleksandra Fedina Gemma Vilà-Nadal Gianni Marone Aarif Eifan Guy W. Scadding David J. Fear Mohamed H. Shamji 《The Journal of allergy and clinical immunology》2021,147(2):663-676
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65.
66.
Woodfolk JA 《Clinical reviews in allergy & immunology》2005,28(1):43-58
Reports of decreased sensitization to cat allergen (Fel d 1) among individuals living with a cat or subjects exposed to high-dose
cat allergen may be explained by the development of a form of high-dose tolerance resulting from natural exposure to an inhalant
allergen. Although the epidemiological data regarding the relationship between exposure and sensitization to Fel d 1 are conflicting,
the ability for high-dose Fel d 1 to induce a characteristic nonallergic immune response with a distinctive serum antibody
profile has been established. Definition of this modified T-helper (Th)2 response to cat allergen, coupled with the renewed
interest in regulatory T cells within the immunology field, has provided an avenue for exploring the mechanism by which IgE
antibody-mediated responses are controlled. There is mounting evidence to suggest that the modified Th2 response is a variation
of the allergic response and that the modified Th2-allergic axis is influenced by allergen dose and genetics. This article
discusses putative immune mechanisms of tolerance within the context of an allergen-specific system. The relevance of high-dose
allergen exposure and alternate factors such as endotoxin to the development of tolerance is considered. Fel d 1 exhibits
unique molecular and immunological characteristics that may contribute to its tolerogenic properties. Major T-cell epitopes
of Fel d 1 that preferentially induce regulatory factors have been defined. Furthermore, hightiter IgE antibody responses
associated with atopic dermatitis are characterized by a defect in the T-cell repertoire that is specific to these epitopes.
Identification of Fel d 1 epitopes that induce interleukin-10 may provide new targets for treatment. 相似文献
67.
Extraembryonic rhythmic motor activity in higher vertebrates, along with the intrinsic motor activity of the embryo, is important
for the normal development of the embryo. This can have different natures in different classes of amniotes (i.e., motor activities
of the amnion, yolk sac, and uterus), but these have similar functional importance. This activity changes reproducibly during
the process of embryogenesis, providing the optimum conditions for normal embryo development. During embryogenesis, a system
for controlling extraembryonic rhythmic motor activity is also formed. There is a trend for the regulation of this activity
to become more complex in mammals as compared with birds. Reptiles have received little study from this point of view. In
addition to regular changes in extraembryonic rhythmic motor activity during embryogenesis which depend on the developmental
stage of the embryo, motor activity can also change in response to changes in a number of environmental factors (for example,
temperature and the gas composition of the air). This demonstrates the possible involvement of embryo-associated extraembryonic
motor activity in adapting the embryo to changing environmental conditions and maintaining homeostasis for the development
of the embryo itself.
Translated from Rossiiskii Fiziologicheskii Zhurnal imeni I. M. Sechenova, Vol. 84, No. 10, pp. 961–968, October, 1998. 相似文献
68.
Y. Ma S. Ren W. M. Pandak X. Li Y. Ning C. Lu F. Zhao L. Yin 《Inflammation research》2007,56(12):495-501
Objective: To investigate the expression of steroidogenic acute regulatory protein (StAR) in macrophages and the effects of inflammatory
cytokines on StAR expression.
Methods: The macrophages isolated from ApoE knockout mice and C57BL/6J mice and RAW264.7 cells (a cell line from mouse macrophage.
ATCC Number: TIB-71TM) were cultured in DMEM containing 10% fetal bovine serum. RAW264.7 cells were treated with different inflammatory cytokines
(TNF-α, IFN-γ and TGF-β1) and 8-Br-cAMP, a cAMP analog. RT-PCR and Western blot analysis were applied to evaluate the effects
of inflammatory cytokines on StAR expression.
Results: RT-PCR and Western blot analysis demonstrated the expression of StAR in the macrophages isolated from ApoE knockout mice,
C57BL/6J mice and RAW264.7 cells. Proinflammatory cytokines TNF-α and IFN-γ significantly decreased StAR mRNA and protein
levels in RAW264.7 cells. The inhibition was dose- and time-dependent. In contrast, anti-inflammatory cytokine TGF-β1 increased
StAR mRNA and protein levels. At 1:15 molecular ratio, TGF-β1 blocked the down-regulation of StAR expression mediated by TNF-α.
cAMP also induced StAR expression in RAW264.7 cells. When the cells were co-treated with 8-Br-cAMP and TNF-α, 8-Br-cAMP failed
to induce StAR expression.
Conclusion: Our results provide interesting evidence that inflammatory cytokines regulate StAR expression in macrophages.
Received 12 August 2006; returned for revision 28 September 2006; returned for final revision 28 May 2007; accepted by M.
Katori 22 June 2007 相似文献
69.
1978—1987年北京市十六所大学本科生因精神疾病休学、退学情况分析 总被引:9,自引:2,他引:9
本文对北京市十六所大学十年来因精神疾病休学、退学的资料进行了分析。结果表明,因精神疾病休学率有所上升,精神疾病是大学生因病休、退学的主要原因,其中以神经症为主。因精神疾病的休退学率以二、三年级学生,及理工科大学学生最高。 相似文献
70.
D R Springall N B Ibrahim J Rode M S Sharpe S R Bloom J M Polak 《The Journal of pathology》1986,150(3):151-162
Several recent studies have confirmed the endocrine nature of small cell carcinoma of the lung. In extra-pulmonary sites, small cell 'undifferentiated' carcinomas have classical morphological features similar to their pulmonary counterpart. We therefore investigated, using immunocytochemistry, the possibility that the non-pulmonary neoplasms may also be endocrine in nature. Sections of 29 small cell carcinomas from oesophagus, stomach, larynx, colon and urinary bladder were immunostained using antisera to protein gene product 9.5 (PGP 9.5), neuron-specific enolase (NSE), cytokeratin, leucocyte common antigen and peptides including bombesin, the C-flanking peptide of human probombesin, adrenocorticotrophic hormone, neurotensin, calcitonin and pancreatic polypeptide. All the tumours showed immunoreactivity for at least one of the two general endocrine markers PGP 9.5 and NSE. Twenty-three of the 29 cases were immunoreactive for PGP 9.5, 27 for NSE. All were positive for cytokeratin and negative for leucocyte common antigen. Of the regulatory peptides, immunoreactivity was obtained with antisera to bombesin (one case), the C-flanking peptide of human pro-bombesin (14 cases), adrenocorticotrophic hormone (one case) and calcitonin (three cases). No PGP 9.5-, NSE- or peptide-like immunoreactivity was detected in 25 control tumours from similar sites, including lymphomas and poorly differentiated tumours. These results suggest that non-pulmonary small cell carcinoma has an endocrine character. 相似文献