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941.
942.
943.
Emmanuel Kuntsche Bruce Simons-Morton Tom ter Bogt Inmaculada Sánchez Queija Victoria Mu?oz Tinoco Margarida Gaspar de Matos Massimo Santinello Michela Lenzi the HBSC Peer Culture Focus Group 《International journal of public health》2009,54(Z2):243-250
Objective:
Because the potential for electronic media communication (EMC) has increased greatly, it is of interest to describe trends in EMC between adolescents and their friends and to investigate whether EMC facilitate or supersede face-to-face contacts among peers. 相似文献944.
Different mechanisms of inhibition of nerve terminals by botulinum and snake presynaptic neurotoxins
Cesare Montecucco Ornella Rossetto Paola Caccin Michela Rigoni Luca Carli Laura Morbiato Lucia Muraro Marco Paoli 《Toxicon》2009,54(5):561-2173
The different mode of action on peripheral nerve terminals of the botulinum neurotoxins and of the snake presynaptic phospholipase A2 neurotoxins is reviewed here. These two groups of toxins are highly toxic because they are neurospecific and at the same time are enzymes that can modify many substrate molecules before being inactivated. The similarity of symptoms they cause in humans derives from the fact that both botulinum neurotoxins (seven serotypes named A-G) and snake presynaptic PLA2 neurotoxins block the nerve terminals and that peripheral cholinergic terminals are major targets. Given this general similarity of targets and clinical symptoms, the specific molecular and cellular mechanisms at the basis of their action are very different. This difference appears evident from the beginning of intoxication, i.e. neurotoxins binding to peripheral nerve terminals and proceeds with the different site of actions and molecular targets. 相似文献
945.
Alessandro Ascione Barbara Capecchi Laura Campitelli Valentina Imperiale Michela Flego Silvia Zamboni Mara Gellini Isabella Alberini Eliana Pittiglio Isabella Donatelli Nigel J. Temperton Maurizio Cianfriglia 《Antiviral research》2009,83(3):238-244
Effective diagnostic and therapeutic strategies are needed to control and combat the highly pathogenic avian influenza virus (AIV) subtype H5N1. To this end, we developed human monoclonal antibodies (mAbs) in single chain fragment variable (scFv) format towards the H5N1 avian influenza virus to gain new insights for the development of immunotherapy against human cases of H5N1. Using a biopanning based approach a large array of scFvs against H5N1 virus were isolated from the human semi-synthetic ETH-2 phage antibody library. H5N1 ELISA-positive scFvs with unique variable heavy (VH) and light (VL) chain gene sequences showed different biochemical properties and neutralization activity across H5N1 viral strains. In particular, the scFv clones AV.D1 and AV.C4 exerted a significant inhibition of the H5N1 A/Vietnam/1194/2004 virus infection in a pseudotype-based neutralization assay. Interestingly, these two scFvs displayed a cross-clade neutralizing activity versus A/whooping swan/Mongolia/244/2005 and A/Indonesia/5/2005 strains. These studies provide proof of the concept that human mAbs in scFv format with well-defined H5N1 recognition patterns and in vitro neutralizing activity can be easily and rapidly isolated by biopanning selection of an entirely artificial antibody repertoire using inactivated H5N1 virus as a bait. 相似文献
946.
Michela Zanetti Alessandra Bosutti Clara Ferreira Pierandrea Vinci Gianni Biolo Maurizio Fonda Matteo Valente Luigi Cattin Gianfranco Guarnieri Rocco Barazzoni 《Clinical and experimental medicine》2009,9(3):243-248
Metabolic syndrome is characterized by increased cardiovascular risk. Pentraxin 3 (PTX3), an acute phase protein, is involved
in atherosclerosis. No information is available on PTX3 plasma concentrations in metabolic syndrome and on its associations
with metabolic alterations and subclinical atherosclerosis. The aim of this study was to assess PTX3 plasma levels in metabolic
syndrome patients compared to control subjects and their potential associations with anthropometric and clinical components
of the syndrome as well as with carotid artery intima-media thickness (cIMT), a marker of subclinical atherosclerosis. Plasma
was obtained from metabolic syndrome patients (NCEP-ATP III criteria n = 41, 20 M/21F) and by age-matched control subjects (n = 32, 16 M/16F). PTX3 was measured using sandwich ELISA and cIMT with ultrasound. Compared to those of the control subjects,
plasma levels of PTX3 were higher (+~100%, P = 0.0009) in metabolic syndrome patients. In univariate analysis, plasma PTX3 was negatively (P = 0.005) associated with high-density lipoprotein (HDL) cholesterol and positively (P = 0.046) with plasma triglycerides and with cIMT (P = 0.045) in the patients (n = 41). In multivariate analysis the direct association between PTX3 and cIMT was no longer significant after correction for
HDL. None of these associations were detected in the control patients. These data demonstrate that PTX3, a novel marker of
vascular disease, is higher in patients with metabolic syndrome associated with subclinical atherosclerosis. In addition,
PTX3 is significantly independently correlated with low HDL cholesterol, but not with cIMT, suggesting a novel association
between PTX3 and atherogenic lipid profile. 相似文献
947.
Michela Cesco-Gaspere Emma Morris Hans J. Stauss 《Clinical and experimental medicine》2009,9(2):81-92
Despite the continuous advances in immunology and cancer biology, haematological malignancies are often incurable. Conventional
chemotherapy and radiation are efficacious for some lymphoma and leukaemia, however relapse and progressive disease often
occurs. The evidence that the immune system can play an essential role in controlling cancer progression provide a basis for
the development of active therapies, such as immunization, aimed to evoke or amplify a tumour-specific immune response. However,
the inability of the patient’s own immune system to mount effective responses against tumour antigens is a major limit of
vaccination approaches. The adoptive transfer of effectors of the adaptive immune system is an attractive strategy to circumvent
the limitations of autologous immune responses. Donor lymphocyte infusion and the transfer of monoclonal antibodies (MoAbs)
have been the first forms of adoptive therapy approved for clinical use and are still fundamental components of immunotherapy
of haematological malignancies. Due to the continuous characterization of tumour-specific antigen, the development of tumour-tailored
therapies that exploit the specificity of antibodies and T cell receptors (TCRs) is progressing rapidly. This review highlights
the current advances in the field of adoptive immunotherapy of haematological malignancies, starting by elucidating the ongoing
progress in passive transfer of MoAbs. We will also discuss recent advances in the adoptive transfer with tumour-specific
high avidity T cells, which can be generated ex vivo by the transfer of gene constructs encoding single chain antibodies or
TCRs, thus redirecting T cell specificity to selected tumour antigens. The ability to produce gene-modified T cells of desired
specificity and defined functional activity may improve in the future T cell based immunotherapy of cancer. 相似文献
948.
BACKGROUND: The development of mania or hypomania during antidepressant treatment is a serious complication of the clinical management of bipolar disorder (BP). The primary aim of this study was to evaluate the clinical variables related to antidepressant-induced mania or hypomania (AIM) in patients with BP. METHODS: DSM-IV BP-I or BP-II patients who had had at least one depressive episode treated with antidepressants were considered. Patients were subdivided into two groups according to the presence (n = 30) or absence (n = 106) of manic or hypomanic episodes occurring during antidepressant treatment. Possible predictive clinical variables of AIM were considered: gender, diagnostic subtype, age at onset, duration of illness, duration of untreated illness, type of antidepressant administered, number of previous spontaneous hypomanic or manic episodes, number of previous depressive episodes, presence of lifetime suicide attempts, presence of mood stabilizer treatments, presence of psychotic symptoms during spontaneous episodes, family history for psychiatric disorders in first degree relatives. Data were compared between the two groups, with (AIM+) and without (AIM-) antidepressant-induced mania, using Student's t tests and chi-square tests. RESULTS: The lack of mood stabilizer treatments during antidepressant therapy (chi-square = 37.602, df = 1, p < 0.001) and the exposure to tricyclic antidepressants (chi-square = 4.901, df = 1, p < 0.05) resulted significantly associated to the development of AIM. LIMITATIONS: This study was not done under controlled conditions and the relatively small sample studied warrants further replications. CONCLUSIONS: These results point out the risk of mania induction associated to the use of tricyclic antidepressants in BP patients, mainly in absence of adequate mood stabilizers. 相似文献
949.
Mobilization of bone marrow-derived hematopoietic and endothelial stem cells after orthotopic liver transplantation and liver resection 总被引:4,自引:0,他引:4
950.
Nucleofection is an efficient nonviral transfection technique for human bone marrow-derived mesenchymal stem cells 总被引:5,自引:0,他引:5
Aluigi M Fogli M Curti A Isidori A Gruppioni E Chiodoni C Colombo MP Versura P D'Errico-Grigioni A Ferri E Baccarani M Lemoli RM 《Stem cells (Dayton, Ohio)》2006,24(2):454-461
Viral-based techniques are the most efficient systems to deliver DNA into stem cells because they show high gene transduction and transgene expression in many cellular models. However, the use of viral vectors has several disadvantages mainly involving safety risks. Conversely, nonviral methods are rather inefficient for most primary cells. The Nucleofector technology, a new nonviral electroporation-based gene transfer technique, has proved to be an efficient tool for transfecting hard-to-transfect cell lines and primary cells. However, little is known about the capacity of this technique to transfect adult stem cells. In this study, we applied the Nucleofector technology to engineer human bone marrow- derived mesenchymal stem cells (hMSCs). Using a green fluorescent protein reporter vector, we demonstrated a high transgene expression level using U-23 and C-17 pulsing programs: 73.7%+/-2.9% and 42.5%+/-3.4%, respectively. Cell recoveries and viabilities were 38.7%+/-2.9%, 44.5%+/-3.9% and 91.4%+/-1.3%, 94.31%+/-0.9% for U-23 and C-17, respectively. Overall, the transfection efficiencies were 27.4%+/-2.9% (U-23) and 16.6%+/-1.4% (C-17) compared with 3.6%+/-2.4% and 5.4%+/-3.4% of other nonviral transfection systems, such as FUGENE6 and DOTAP, respectively (p<.005 for all comparisons). Nucleofection did not affect the immunophenotype of hM-SCs, their normal differentiation potential, or ability to inhibit T-cell alloreactivity. Moreover, the interleukin-12 gene could be successfully transfected into hMSCs, and the immunomodulatory cytokine was produced in great amount for at least 3 weeks without impairment of its biological activity. In conclusion, nucleofection is an efficient nonviral transfection technique for hMSCs, which then may be used as cellular vehicles for the delivery of biological agents. 相似文献