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61.
Hentchel-Franks K Lozano D Eubanks-Tarn V Cobb B Fan L Oster R Sorscher E Clancy JP 《American journal of respiratory cell and molecular biology》2004,31(2):140-146
We investigated cystic fibrosis (CF) transmembrane conductance regulator (CFTR) regulation by A2 adenosine (Ado) receptors and beta2 adrenergic receptors in CFTR-corrected CFBE41o- airway cells and human subjects. CFBE41o- cells stimulated with Ado (10 microM), isoproterenol (Iso, 10 microM), or Ado + Iso (10 microM each) elevated cyclic AMP (cAMP) above control conditions (P < 0.001), with the Iso conditions increasing cAMP approximately 10-fold above that produced by Ado alone (P < 0.001). All agonist conditions had similar effects on short circuit current at 10 and 25 microM, with no further currents produced by subsequent stimulation with forskolin (20 microM). CFTR dependence was demonstrated by glybenclamide block of agonist-stimulated currents. Nasal potential difference studies in normal (n = 50) subjects demonstrated that Ado (10 microM) and Ado + Iso (10 microM each) produced more polarization compared with Iso (10 microM Ado increase = 44%, 10 microM Ado + Iso increase = 52%, P < 0.05 for each condition compared with Iso alone). Studies completed in patients with CF (n = 10, "severe" genotypes) confirmed that Ado-stimulated polarization was CFTR-dependent. Together, these results indicate that Ado is a potent Cl- secretagogue in vivo, with relatively small effects on cAMP levels despite strong effects on CFTR-dependent short circuit current and nasal Cl- transport. These findings support growing evidence indicating a role for Ado regulation of CFTR-dependent Cl- secretion in vivo. 相似文献
62.
Immunoassay targeting nonstructural protein 5 to differentiate West Nile virus infection from dengue and St. Louis encephalitis virus infections and from flavivirus vaccination 下载免费PDF全文
Wong SJ Boyle RH Demarest VL Woodmansee AN Kramer LD Li H Drebot M Koski RA Fikrig E Martin DA Shi PY 《Journal of clinical microbiology》2003,41(9):4217-4223
West Nile virus (WNV) is an emerging flavivirus that has caused frequent epidemics since 1996. Besides natural transmission by mosquitoes, WNV can also be transmitted through blood transfusion and organ transplantation, thus heightening the urgency of development of a specific and rapid serologic assay of WNV infection. The current immunoassays lack specificity because they are based on detection of antibodies against WNV structural proteins and immune responses to structural proteins among flaviviruses cross-react to each other. Here, we describe microsphere immunoassays that detect antibodies to nonstructural proteins 3 and 5 (NS3 and NS5). In contrast to immunoassays based on viral envelope and NS3 proteins, the NS5-based assay (i) reliably discriminates between WNV infections and dengue virus or St. Louis encephalitis virus infections, (ii) differentiates between flavivirus vaccination and natural WNV infection, and (iii) indicates recent infections. These unique features of the NS5-based immunoassay will be very useful for both clinical and veterinary diagnosis of WNV infection. 相似文献
63.
64.
Stone VE 《Current HIV/AIDS reports》2005,2(4):189-193
Racial/ethnic minorities in the United States are disproportionately affected by HIV/AIDS. In addition to having higher rates
of HIV/AIDS, minorities with HIV/AIDS have higher mortality rates than others in the United States. Disparities in the care
received by minorities living with HIV/AIDS contribute to these higher mortality rates. This article provides a review of
HIV/AIDS health care disparities and explores providers’ contributions to these disparities. An important source of provider
contribution to disparities appears to be differential prescribing based on perceptions and assumptions that minority patients
may have lower adherence to highly active antiretroviral therapy. Literature regarding this topic is reviewed and strategies
for reducing disparities are suggested. 相似文献
65.
Rapid expansion and IL-4 expression by Leishmania-specific naive helper T cells in vivo 总被引:2,自引:0,他引:2
CD4 T cells are pivotal for effective immunity, yet their initial differentiation into effector subsets after infection remains poorly defined. We examined CD4 T cells specific for the immunodominant Leishmania major LACK antigen using MHC/peptide tetramers and IL-4 reporter mice. Comprising approximately 15 cells/lymph node in naive mice, LACK-specific T cells expanded over 100-fold, and 70% acquired IL-4 expression by 96 hr. Despite their pathogenic role in susceptible mice, LACK-specific precursor frequency, expansion, and IL-4 expression were comparable between susceptible and resistant mice. When injected with unrelated antigen, Leishmania efficiently activated IL-4 expression from naive antigen-specific T cells. CD4 subset polarization in this highly characterized model occurs independently from IL-4 expression by naive T cells, which is activated indiscriminately after parasitism. 相似文献
66.
Sam Tsemberis Gregory McHugo Valerie Williams Patricia Hanrahan Ana Stefancic 《Journal of community psychology》2007,35(1):29-42
Reliable and valid longitudinal residential histories are needed to assess interventions to reduce homelessness and increase community tenure. This study examined the test‐retest reliability, sensitivity to change, and concurrent validity of the Residential Time‐Line Follow‐Back (TLFB) Inventory, a method used to record residential histories in the Collaborative Program to Prevent Homelessness (n = 1,381). The Residential TLFB Inventory yielded temporally stable aggregate measures of duration in residential categories, and it revealed significant differences in change over time when contrasting study groups. A comparison of agency and participant data at one site. 相似文献
67.
Suzanne Lombard-Platet Valerie Meyer Rhodri Ceredig 《Clinical & developmental immunology》1997,5(2):115-120
Pro-B cells are early B-cell progenitors that retain macrophage potential. We have studied
MHC class II molecules and invariant chain inducibility on four class II negative mouse pro-
B-cell clones. We analyzed the effects of IL-4 and IFN-γ, which represent the major inducers
of class II in the B-lymphoid and monocytic/macrophage lineages, respectively. After 48 h of
treatment with either cytokine, three pro-B-cell clones (C2.13, A1.5, and F2.2) expressed intracellular
invariant chain and cell-surface class II molecules. One clone (D2.1) remained negative.
As already reported, more differentiated 70Z/3 pre-B cells were inducible by IL-4 only.
These data suggest that the induction of class II and invariant-chain genes are subject to regulation
throughout B-cell differentiation. 相似文献
68.
Christine R. Bryke Valerie Lindgren Julie S. Fryburg Teresa L. Yang-Feng 《American journal of medical genetics. Part A》1990,36(2):247-250
A previously unreported isodicentric chromosome 18 was discovered in an abnormal infant boy whose mosaic karyotype was 46, XY/46,XY,–18, + idic(18)(q12.2). His constellation of congenital anomalies was typical of the 18q-syndrome. The clinical and cytogentic characteristics of this patient are reported, and the literature concerning isochromosomes of 18 is reviewed. 相似文献
69.
70.
Summary Isatin -thiosemicarbazone (ITSC) is well known for its chemoprophylactic activity against certain poxvirus infections. The influence of 20 M ITSC on the development of neurovaccinia virus particles in infected embryo rabbit kidney cells has been studied by electron microscopy. It is shown that ITSC exerts an intracellular effect, permitting the formation of immature and abnormal forms, but preventing the normal development of these to give mature infective virus particles. The effects are compared with the normal development of mature virus particles as observed by us and as described by other authors from their electron microscopy studies. 相似文献