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81.
Adenoviral-mediated gene transfer to fetal pulmonary epithelia in vitro and in vivo. 总被引:4,自引:3,他引:4 下载免费PDF全文
P B McCray Jr K Armstrong J Zabner D W Miller G A Koretzky L Couture J E Robillard A E Smith M J Welsh 《The Journal of clinical investigation》1995,95(6):2620-2632
Vector-mediated gene transfer offers a direct method of correcting genetic pulmonary diseases and might also be used to correct temporary abnormalities associated with acquired, nongenetic disorders. Because the fetus or newborn may be a more immune tolerant host for gene transfer using viral vectors, we used replication defective recombinant adenoviral vectors to test the feasibility of gene transfer to the fetal pulmonary epithelium in vitro and in vivo. Both proximal and distal epithelial cells in cultured fetal lung tissues from rodents and humans diffusely expressed the lacZ transgene 3 d after viral infection. In vivo gene delivery experiments were performed in fetal mice and lambs. Delivery of Ad2/CMV-beta Gal to the amniotic fluid in mice produced intense transgene expression in the fetal epidermis and amniotic membranes, some gastrointestinal expression, but no significant airway epithelial expression. When we introduced the adenoviral vector directly into the trachea of fetal lambs, the lacZ gene was expressed in the tracheal, bronchial, and distal pulmonary epithelial cells 3 d after viral infection. Unexpectedly, reactive hyperplasia and squamous metaplasia were noted in epithelia expressing lacZ in the trachea, but not in the distal lung of fetal lambs. 1 wk after infection, adenovirus-treated fetuses developed inflammatory cell infiltrates in the lung tissue with CD4, CD8, IgM, and granulocyte/macrophage positive immune effector cells. Transgene expression faded coincident with inflammation and serologic evidence of antiadenoviral antibody production. While these studies document the feasibility of viral-mediated gene transfer in the prenatal lung, they indicate that immunologic responses to E1-deleted recombinant adenoviruses limit the duration of transgene expression. 相似文献
82.
Prevalence of cytomegalovirus antibody in hemophiliacs and homosexuals infected with human immunodeficiency virus type 1 总被引:1,自引:0,他引:1
We determined the prevalence of antibody to cytomegalovirus (CMV) in the sera of non-homosexual hemophilia patients and homosexual men infected with the human immunodeficiency virus type 1 (HIV-1). CMV antibody testing by latex agglutination revealed 33 of 58 HIV-1 infected hemophiliacs (57%) were antibody-positive compared with 54 of 54 HIV-1 infected asymptomatic non-hemophiliac homosexuals (100%) (p less than .001). Nine of 15 hemophiliacs (60%) with symptomatic HIV-1 infection were CMV antibody-positive. We also tested 22 HIV-1 antibody-negative hemophiliacs who had received non-heat treated factor concentrates. 14 of these 22 (64%) were CMV antibody-positive compared with 57% of HIV-1 antibody-positive hemophiliacs. We conclude 1) there is little correlation between transmission of HIV-1 and CMV by factor concentrates, 2) the presence of CMV antibody does not appear to be associated with clinical stage of HIV-1 infection in hemophiliacs, and 3) there may be a significant number of CMV antibody-negative hemophiliacs with HIV-1 infection at risk for primary infection and subsequent disease if CMV seronegative blood products are not provided for future transfusions. 相似文献
83.
84.
Inge S Zuhorn Dharamdajal Kalicharan George T Robillard Dick Hoekstra 《Molecular therapy》2007,15(5):946-953
For a variety of reasons, including production limitations, potential unanticipated side effects, and an immunological response upon repeated systemic administration, virus-based vectors are as yet not ideal gene delivery vehicles, justifying further research into alternatives. Unlike viral vectors, non-viral vectors pose minimal health risks, but to meet therapeutic requirements their efficacy needs major improvement. This goal may be accomplished by better defining the mechanism of non-viral gene delivery and exploiting specific cellular properties. Here we demonstrate that transfection of epithelial cells with lipoplexes is almost exclusively mediated by the beta1 integrin cell surface receptor. More important, we show that in general, adhesion receptors can be exploited by lipoplexes to gain access to cells, including difficult-to-transfect primary neural stem cells and suspension cells, thereby leading to productive transfection. We propose that adhesion receptors serve as "natural" receptors for lipoplexes. As no natural cellular receptors for lipoplexes have previously been identified, our results are an important step forward in understanding the mechanisms of non-viral gene delivery. Moreover, the finding that adhesion receptors mediate efficient non-viral gene delivery paves the way for the optimization of (standard) transfection procedures as well as ex vivo gene therapy protocols using non-viral vectors. 相似文献
85.
Background and Objectives IgA deficiency is common (1/500) and up to 40% of affected individuals will develop anti‐IgA. A few studies suggested that passive transfusion of anti‐IgA was not associated with an increased risk of allergic reactions. This study was designed to assess the safety of transfusing blood components containing anti‐IgA. Materials and Methods IgA‐deficient blood donors with and without anti‐IgA were identified from Héma‐Québec’s (HQ) computerized database. IgA deficiency was confirmed by an ELISA method and the presence of anti‐IgA by a passive hemagglutination assay. Blood donations from IgA‐deficient donors issued to hospitals between March 1999 and December 2004 were retrieved. Medical charts of recipients were reviewed for the occurrence of a suspected transfusion reaction. Presence and nature of transfusion reactions were assessed blindly by an adjudicating committee. Results A total of 323 IgA‐deficient blood products were issued by HQ to 55 hospitals. Of these, 48 agreed to participate [315 blood products (97·5%)]. A total of 272 products were transfused: 174 contained anti‐IgA, and 98 did not. Only two minor allergic reactions occurred in each group. Incidence of allergic reactions was 1·15% in the anti‐IgA group and 2·04% in the group without anti‐IgA (P = 0·91). There was no anaphylactic reaction in either group. Conclusions This study indicates that the proportion of allergic reactions does not appear to be greater in recipients of blood components containing anti‐IgA compared to recipients of non‐anti‐IgA‐containing components. Allowing donations from IgA‐deficient donors with anti‐IgA may therefore be contemplated. 相似文献
86.
Fiedler T Büning C Reuter W Pitre G Gentz E Schmidt HH Büttner J Ockenga J Gerloff T Meisel C Lochs H Roots I Köpke K Johne A 《European journal of clinical pharmacology》2007,63(10):917-925
Background The role of the single nucleotide polymorphisms (SNPs) on positions 2677G>T/A and 3435C>T of the multi-drug-resistance gene
1 (MDR1) in inflammatory bowel disease (IBD) remains unclear.
Aims To further elucidate the potential impact of MDR1 two-locus genotypes on susceptibility to IBD and disease behaviour.
Patients and methods Three hundred eighty-eight German IBD patients [244 with Crohn’s disease (CD), 144 with ulcerative colitis (UC)] and 1,005
German healthy controls were genotyped for the two MDR1 SNPs on positions 2677G>T/A and 3435C>T. Genotype–phenotype analysis was performed with respect to disease susceptibility
stratified by age at diagnosis as well as disease localisation and behaviour.
Results Genotype distribution did not differ between all UC or CD patients and controls. Between UC and CD patients, however, we observed
a trend of different distribution of the combined genotypes derived from SNPs 2677 and 3435 (χ2 = 15.997, df = 8, p = 0.054). In subgroup analysis, genotype frequencies between UC patients with early onset of disease and controls showed
significant difference for combined positions 2677 and 3435 (χ2 = 16.054, df = 8, p = 0.034 for age at diagnosis ≥25, lower quartile). Herein the rare genotype 2677GG/3435TT was more frequently observed (odds
ratio = 7.0, 95% confidence interval 2.5 – 19.7). In this group severe course of disease behaviour depended on the combined
MDR1 SNPs (χ2 = 16.101, df = 6, p = 0.017 for age at diagnosis ≥25). No association of MDR1 genotypes with disease subgroups in CD was observed.
Conclusions While overall genotype distribution did not differ, combined MDR1 genotypes derived from positions 2677 and 3435 are possibly associated with young age onset of UC and severe course of disease
in this patient group. 相似文献
87.
88.
O'Connor KP Aardema F Robillard S Guay S Pélissier MC Todorov C Borgeat F Leblanc V Grenier S Doucet P 《Acta psychiatrica Scandinavica》2006,113(5):408-419
Objective: To compare cognitive behaviour therapy (CBT) with CBT plus medication; medication alone; and placebo in the treatment of adult obsessive–compulsive disorder (OCD). Method: Forty‐eight participants (43 completers) were recruited into two protocols. In the first protocol, 21 people with OCD were randomly allocated to either a standard medication (fluvoxamine) or standard placebo condition for a 5‐month period. Both these groups subsequently received CBT for a further 5 months. In the second protocol, 22 people with OCD received CBT, one group was already stabilized on an antidepressant of choice; the second group was drug naïve. Results: All active treatments, but not the placebo, showed clinical improvement. There was no difference in treatment response to CBT regardless of whether participants had previously received medication or placebo. Conclusion: CBT has a more specific antiobsessional effect than medication but CBT plus medication shows greatest overall clinical improvement in mood. 相似文献
89.
G Jego N Robillard D Puthier M Amiot F Accard D Pineau J L Harousseau R Bataille C Pellat-Deceunynck 《Blood》1999,94(2):701-712
Circulating plasma cells in 10 cases of reactive plasmacytosis had a shared phenotype with early plasma cell (CD19(+) CD38(+) CD138(+) CD40(+) CD45(+) CD11a+ CD49e- CD56(-)). In most cases, a minor subpopulation of CD28(+) plasma cells was also detected. Reactive plasma cells were highly proliferative, suggesting the presence of circulating progenitors (plasmablasts). After CD138(+) plasma cell removal, highly proliferative CD138(-) plasmablasts differentiated into CD138(+) plasma cells within a few days. This differentiation, which was associated with increased CD38 and decreased HLA-DR expression, was further confirmed by a large increase in intracellular Ig content (associated with Ig secretion) and was concomitant with extensive secretion of interleukin-6 (IL-6). The addition of neutralizing anti-IL-6 and anti-CD126 (IL-6 receptor) monoclonal antibodies totally prevented Ig secretion and cell differentiation by inducing apoptosis of plasmablasts, which indicates that IL-6 is an essential survival factor for plasmablasts. This report provides the first characterization of normal plasmablasts and shows that their phenotype is not exactly that of multiple myeloma cells. 相似文献
90.
Neil R Price Amanda Charlton Itayi Simango Grahame HH Smith 《Journal of paediatrics and child health》2014,50(10):E102-E105
Aim: To explore the issue of appropriate management of testicular microlithiasis. We report the third ever case of tumour arising from a testis previously known to have microlithiasis in childhood and review the literature to provide an evidence‐based approach to management of testicular microlithiasis. Methods: Case report and review of previous literature. Results and Conclusions: Although there is a strong association between testicular microlithiasis and testicular malignancy at diagnosis, there are only three reported cases of subsequent tumour development in childhood. Testicular microlithiasis is an increasingly recognised entity. There is insufficient evidence in the current literature to support any regime of clinical surveillance. Self‐examination is the most important factor in the early detection of testicular malignancy. 相似文献