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41.
N. Freudenberg P. Rahner C. Darda U. N. Riede M. Schubert K. Frenzer-Welle A. Kiss G. Veres T. Nees R. Lamers C. Kortsik 《Virchows Archiv : an international journal of pathology》1996,428(3):187-194
We investigated the reaction of the cellular immune system of liver and blood in the C57BL/6 mouse to a metastasizing Lewis lung carcinoma. The cellular immune system of the liver consists of mature and immature macrophages, B-cells, T-cells including their subpopulations, and natural killer cells, and their percentage frequencies differ significantly from those in the corresponding mononuclear blood cell (MBC) compartment. This suggests that the hepatic immune cells represent a system with autonomous function showing a typical homing of its members. Imminent metastasis to the liver is signalled by impressive alterations in the percentage frequencies of nonparenchymal liver cells (NPLC). There are a dramatic loss of mature macrophages, an increase in immature macrophages, a reduction of T-helper cells leading to a low CD4/CD8 ratio, and an increase in natural killer cells. In the blood, the corresponding precursor cells show comparable changes with a delay of at least 2 days. Early metastasis is accompanied by a significant increase in mononuclear NPLC producing tumour necrosis factor . The alterations in percentage frequencies of the NPLC during tumour metastasis differ markedly from the changes in these cells in the liver during endotoxinaemia. 相似文献
42.
Immunohistochemical characterization of an anti-epithelial monoclonal antibody (mAB lu-5) 总被引:7,自引:0,他引:7
J. von Overbeck C. Stähli F. Gudat H. Carmann C. Lautenschlager U. Dürmüller B. Takacs V. Miggiano Th. Staehelin Ph. U. Heitz 《Virchows Archiv : an international journal of pathology》1985,407(1):1-12
Summary A mouse monoclonal antibody (mAB lu-5) was prepared using a lung cancer cell line as an antigen. The selected clone produces an IgG with a gamma-1 heavy chain and a kappa-light-chain. Immunohistochemical testing of mAB lu-5 on 117 normal tissue biopsies and 474 tumours revealed reactivity with an intracytoplasmic, formaldehyderesistant antigen present in most epithelial and mesothelial cells, but absent in mesenchymal cells. The antibody can therefore be used as a first order, pan-epithelial marker. It proved also useful for fast tumour diagnosis on frozen sections. 相似文献
43.
The Yin-Yang of tumor-associated macrophages in neoplastic progression and immune surveillance 总被引:5,自引:1,他引:5
Paola Allavena Antonio Sica Cecilia Garlanda Alberto Mantovani 《Immunological reviews》2008,222(1):155-161
Summary: An intrinsic (oncogene-driven) pathway and an extrinsic (microenvironment-driven) pathway connect inflammatory reactions and cancer. M2-polarized tumor-associated macrophages and the related myeloid-derived suppressor cells are key prototypic components of smoldering inflammation driving neoplastic progression. However, mononuclear phagocytes can exert anti-tumor activity by killing tumor cells and eliciting tissue disruptive reactions (M1), a likely scenario in the early phases of carcinogenesis of immunogenic tumors and following therapeutic intervention. Shifting the macrophage balance represents a viable therapeutic target. Herein, the 'macrophage balance' is discussed in the context of the apparent paradox of tumor promotion by innate immunity-driven inflammation and the seemingly opposed tumor surveillance by adaptive immune responses. 相似文献
44.
Kazuki Nabeshima Teruhiko Inoue Yoshiya Shimao Hiroaki Kataoka M. Koono 《Virchows Archiv : an international journal of pathology》1998,433(3):243-253
We have already presented a two-dimensional cell motility assay using a highly metastatic variant (L-10) of human rectal
adenocarcinoma cell line RCM-1 as a motility model of tumour cells of epithelial origin. In this model, L-10 cells showed
locomotion as a coherent sheet when stimulated with 12-O-tetradecanoylphorbol-13-acetate (TPA), and we called this type of movement ”cohort migration”. Electron and immunoelectron
microscopic study of the migrating cell sheets demonstrated localized release from cell–cell adhesion only at the lower portion
of the cells with loss of E-cadherin immunoreactivity, and this change was associated with increased tyrosine phosphorylation
of the E-cadherin–catenin complex, including β-catenin. Cell–extracellular matrix (ECM) interactions involved in this TPA-induced
cohort migration and their effect on tyrosine phosphorylation of the E-cadherin-catenin complex have now been investigated.
L-10 cell cohort migration was almost completely inhibited by addition of Arg-Gly-Asp (RGD) peptide into the medium, and thus
RGD dependent. Cohort migration was stimulated on type I and IV collagens, fibronectin (FN)- and laminin-coated substratum,
but was inhibited by RGD only on FN-coated surface. By using immunofluorescent techniques, FN was demonstrated preferentially
around migrating cells, and a protein synthesis inhibitor, cycloheximide, inhibited the migration by about 75%. FN produced
by L-10 cells were found to be mostly EDA+ FN when analysed by RT-PCR. Moreover, anti-FN antibody, but not anti-vitronectin
antibody, inhibited the TPA-induced cohort migration almost completely. Thus, it was likely that L-10 cells produced FN themselves
and moved on the FN substrate in an RGD-dependent manner. However, stimulation of migration by type I collagen coating and
inhibition by RGD treatment did not affect the tyrosine phosphorylation of the E-cadherin–catenin complex induced by TPA,
indicating that cell–cell interactions were adjusted to suit cell migration, irrespective of the condition of cell–ECM adhesion,
during TPA-induced cohort migration.
Received: 31 December 1997 / Accepted: 2 April 1998 相似文献
45.
目的 观察小鼠TIM2转基因H22肝癌细胞瘤苗在小鼠体内的成瘤作用 ,初步研究其免疫原性.方法 构建TIM2基因真核表达载体pIRES2-EGFP - TIM2,脂质体法转染H22细胞,制备得到TIM2基因修饰的H22细胞瘤苗,建立小鼠肝癌移植瘤模型,观察其在小鼠体内的成瘤作用.结果 成功得到TIM2基因修饰的H22 细胞瘤苗,免疫接种小鼠后,可明显抑制小鼠体内肿瘤的发生和发展;给予H22-TIM2接种的小鼠CD4亚群、CD4/CD8比值显著高于H22-EGFP 细胞接种组、荷瘤对照组和正常对照组.结论 TIM2基因修饰H22细胞后,可显著降低H22细胞的体内成瘤性,抑制小鼠肿瘤生长,同时.在体内具有一定的免疫原性,为进一步探讨TIM2 在肿瘤生物治疗中的作用提供了初步的实验依据. 相似文献
46.
Localization of CEA,HCG, Lysozyme,alpha-1-antitrypsin,and alpha-1-antichymotrypsin in gastric cancer and prognosis 总被引:1,自引:0,他引:1
Ch. Wittekind R. Wachner W. Henke S. von Kleist 《Virchows Archiv : an international journal of pathology》1986,409(5):715-724
Summary Carcinoembryonic antigen (CEA),-human chorionic gonadotropin (HCG), alpha-1-antichymotrypsin (ACT), alpha-1-antitrypsin (AAT) and Lysozyme (LYS) were traced by immunoperoxidase staining in gastric carcinomas. The immunohistological results were evaluated in relation to histological types (WHO and Laurén), stage of disease, grade and survival time. CEA was demonstrated in 96% of the tumours, HCG in 34%, ACT in 78%, AAT in 42%, and LYS in 71%. Comparing the staining patterns of the antigens and the intensity of staining some differences were notable. Except for signet-ring cell carcinomas, all of which were intensively positive, CEA expression decreased significantly with loss of differentiation. This observation was not seen with the other marker substances. None of the tested markers was characteristic for one particular histological type, nor could they be correlated with the tumour stage or grade. The marker positivity of CEA, ACT and LYS was not related to survival time. For HCG only, a correlation between tissue expression and a restricted survival time was established. Patients with AAT positive carcinomas had a significantly better survival probability. 相似文献
47.
Wang Z 《Pflügers Archiv : European journal of physiology》2004,448(3):274-286
K+ channels are a most diverse class of ion channels in the cytoplasmic membrane and are distributed widely in a variety of cells including cancer cells. Cell proliferation and apoptosis (programmed cell death or cell suicide) are two counterparts that share the responsibility for maintaining normal tissue homeostasis. Evidence has been accumulating from fundamental studies indicating that tumour cells possess various types of K+ channels, and that these K+ channels play important roles in regulating tumour cell proliferation and apoptosis, i.e. facilitating unlimited growth and promoting apoptotic death of tumour cells. The potential implications of K+ channels as a pharmacological target for cancer therapy and a biomarker for diagnosis of carcinogenesis are attracting increasing interest. This review aims to provide a comprehensive overview of current status of research on K+ channels/currents in tumour cells. Focus is placed on the roles of K+ channels/currents in regulating tumour cell proliferation and apoptosis. The possible mechanisms by which K+ channels affect tumour cell growth and death are discussed. Speculations are also made on the potential implications of regulation of tumour cell proliferation and apoptosis by K+ channels. 相似文献
48.
Summary In 5 cases of invasive ductal and lobular carcinoma of the breast multiple epithelioid and giant cell containing granulomas were detected, localized mainly in circumferential regions, but also in the center of the carcinomas. These granulomas were interpreted as sarcoid-like stromal reactions, occurring as sarcoid-like lesions in uni- and bilateral primaries, in a recurrent tumour, and also in axillary lymph nodes. Histopathologically, these granulomas were not quite uniform, some of them corresponding to typical sarcoidosis, others showing marked proliferations of epithelioid or giant cells or containing fibrinoid exudate or necroses. The granulomas were surrounded by dense infiltrates of mononuclear cells. Tuberculosis and mycosis was excluded. There were no hints of generalized sarcoidosis. Pathogenetically, these are reactions in the tumour stroma of varying intensity, and are not caused by necroses of the tumour tissue nor by microbial infections. Such tumour-associated sarcoid-like stroma reactions are interpreted as a T-cell mediated immune response to an antigen expression of the carcinoma acting as the local trigger; in 2 cases they were connected with sarcoid-like lesions of the axillary lymph nodes. Their occurrence in bilateral carcinoma of the breast points to an immunological disposition for this special kind of host-versus-tumour response. The intensity of these changes in a recurrent tumour reflects an immunological hypersensitivity reaction.The pathogenetic and differential diagnostic aspects of epithelioid granulomas of the female breast in chronic granulomatous mastitis, panniculitis, foreign body reaction, rare infections, and in therapeutically induced sarcoidosis are described and discussed.Dedicated to Prof. Dr. K. Lennert, Kiel, in Honour of his 65th Birthday 相似文献
49.
M. Vierbuchen S. Schröder G. Uhlenbruck A. Lavena R. Fischer 《Virchows Archiv : an international journal of pathology》1994,424(2):205-211
Forty-six medullary thyroid carcinomas (MTC) were subjected to a qualitative and quantitative characterization of native and sialic acid masked Lewisa (Lea) antigens. Immunohistochemical investigations included monoclonal antibodies (MABs) directed against alpha(2,3)-sialyl-Lea, i.e. CA19-9 (MAB 19-9), native Lea (MAB anti Lea) and alpha(2,3) sialyl type 1 structure, i.e. CA 50 (MAB C50). To detect sialic acid masked Lea reactivity, MAB anti-Lea was also applied to native and enzymatically desialylated tissue sections with and without masking of sialic acid residues by sialic acid and sequence specific lectins. Only 7 MTC (15%) displayed a weak expression of CA19-9, while 16 (33%) showed moderate positive staining for native Lea. Twenty-seven tumours exhibited a strong staining by the N'ase MAB anti Lea staining sequence. The latter could most effectively be inhibited by the simultaneous masking of alpha(2,3)-and alpha-(2,6)-linked sialic acid residues due to the comptetitive binding of sialic acid and sequence specific lectins: Maackia amurensis agglutinin (specific alpha(2,3)-linked sialic acid) and Sambucus nigra agglutinin (specific alpha(2,6)-linked sialic acid). Thus, in MTC the major portion of sialic acid masked Lea antigen reactivity is different from that detected by the MAB 19-9. The antigen reactivity is probably due to Lea structures containing both alpha(2,3) and alpha(2,6)-linked sialic acid residues. A highly significant correlation between the expression of CA50 and that detected by the N'ase MAB anti-Lea staining sequence indicates that the alpha(2,3)-sialyl type 1 chain represents a common intermediate structure within the pathway of the biosynthesis of sialylated Lea antigens, excluding the formation of CA19-9 via the formation of the disialyl type 1 structure. This is subsequently fucosylated to the corresponding sialic acid masked Lea. Preliminary clinicopathological studies indicate that the sialic acid masked Lea antigens detected by the N'ase MAB anti-Lea staining sequence are related to biologically aggressive MTC. 相似文献
50.
ucja Zieliska-Tomczak Piotr Przymuszaa Szymon Tomczak Izabela Krzyko-Pieczka Ryszard Marciniak Magdalena Cerbin-Koczorowska 《Nutrients》2021,13(6)
The growing popularity of health education on social media indicates the need for its appropriate evaluation. This paper aims to present the potential of the Kirkpatrick Model (KM) with New World Kirkpatrick Model (NWKM) additions to evaluate the nutritional education provided by dieticians via Instagram. Instagram profiles of ten dieticians providing nutritional education for their followers were analyzed in March and April 2021. The study sample included profiles of both macro- and micro-influencers. The analyzed quantitative data included Instagram Engagement Rate and the number of likes and comments per post. The qualitative analysis of the comments was performed following the theoretical framework provided by the KM and NWKM. Collected data showed followers’ satisfaction, commitment, and relevance of the presented content, fulfilling the Level 1 of NWKM. Level 2 of NWKM was represented by 4 out of 5 dimensions (knowledge, attitude, confidence, commitment). No comments were found only for skills. Both Levels 3 (Behavior) and 4 (Results) of the KM were met. However, the use of the NWKM for them seems limited. The KM can be used to evaluate nutritional education on social media. The NWKM additions seem applicable mostly for Levels 1 and 2. 相似文献