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1.
Acute and long-term humoral immunity following active immunization of rabbits with inacctivated spores of various Encephalitozoon species 总被引:1,自引:0,他引:1
Sobottka I Iglauer F Schüler T Schmetz C Visvesvara GS Albrecht H Schwartz DA Pieniazek NJ Bartscht K Laufs R Schottelius J 《Parasitology research》2001,87(1):1-6
Microsporidia of the genus Encephalitozoon are increasingly being reported as a cause of severe, often disseminated infections, mainly in patients with acquired immunodeficiency
syndrome (AIDS). Immunological identification of each of the three recognized species (E. cuniculi, E. hellem, and E. intestinalis) requires the availability of specific immune sera. All sera available thus far have been generated by direct inoculation
of rabbits with virulent microsporidian spores. This study demonstrates for the first time that subcutaneous immunization
with inactivated spores of E. cuniculi, E. hellem, or E. intestinalis is capable of generating highly active rabbit hyperimmune sera to the homologous antigens, with maximal titers being 1:5,120,
1:1,280, and 1:2,560, respectively, as determined by the indirect immunofluorescence technique (IIF). Broad cross-reactivity
of the rabbit antisera with all heterologous Encephalitozoon antigens was determined by IIF and immunogold electron microscopy; however, only the E. hellem immune serum strongly cross-reacted with spores of Enterocytozoon bieneusi. During the 35-month follow-up period the antibody titers to the homologous antigens declined to 1:640, 1:160, and 1:320,
respectively. The observed decay curves for antibody titers against E. cuniculi, E. hellem, and E. intestinalis were fitted using mathematical modeling, resulting in a predicted duration for specific immune responses of about 7 years
on average. Knowledge of the magnitude and duration of specific immune responses is a prerequisite for further evaluation
of the concept of using inactivated microsporidian spores in the quest for vaccines against microsporidian infections.
Received: 10 April 2000 / Accepted: 18 July 2000 相似文献
2.
Yinon Ben-Neriah Justus B. Cohen Gideon Rechavi Rina Zakut David Givol 《European journal of immunology》1981,11(12):1017-1020
The polymorphic nature of the immunoglobulin VH genes was investigated by Southern blot analysis of liver DNA of sixteen different mouse strains and hybridization with VH probes. Differences in restriction enzyme pattern (REP) were observed and six different patterns of restriction fragments were found for the sixteen strains analyzed. No equivalent polymorphism was observed in another multigene family, the actins. The six patterns correlate with immunoglobin constant region allotypes (Igh-1). Experiments with Igh-1-congenic strains suggest that the VH REP is linked to immunoglobulin constant region haplotype. Mouse strains which share inherited idiotypes also share identical VH restriction pattern. This provides a structural basis for the genetic linkage between idiotypes and allotypes. It also indicates that different strains carry different VH gene repertoires, which may be the basis for the expression of different inherited idiotypes in various strains. We propose that a VH group is a set of linked genes that are coinherited as a cluster with the constant region genes and that VH and CH can be regarded as an extended haplotype. 相似文献
3.
Researchers have differentiated sons of alcoholics (SOA's) from sons of nonalcoholics (non-SOA's) on various measures of physiological activity that appear to be related to the SOA's increased vulnerability to developing alcohol problems. This article summarizes major findings in the literature and discusses the implications of risk-related physiological characteristics for the future development of alcohol problems. SOA's tend to show signs of physiological activity associated with anxiety states, such as increased heart rate in response to stressful stimuli. Studies also demonstrate that SOA's differ greatly from non-SOA's in their response to alcohol. Drinking alcohol dramatically reduces SOAs' reactivity to both stressful and nonstressful stimuli. Additionally, SOA's appear to be less sensitive to alcohol's intoxicating and impairing effects. However, studies also suggest that some SOA's may experience more of alcohol's rewarding effects for a brief period after drinking. Increased stress-dampening and reduced responsiveness to alcohol's negative effects also appear to predict the development of future alcohol problems and may reflect important vulnerabilities in SOA's. 相似文献
4.
During the course of a so-called posterior vitreous detachment, a thin layer of the posterior vitreous cortex often remains
adherent to the underlying retina. Tangential stretch of this vitreous pseudomembrane may cause vitreomacular traction syndrome,
edema, and macular hole formation. The same process appears to underlie the development of true epimacular membranes (idiopathic
macular pucker). Vitrectomy is generally agreed to be the most appropriate treatment for these clinical situations. We evaluated
the incidence of vitreomacular adhesion and of visual improvement after vitrectomy of eyes with macular pucker (group 1; n=60) and vitreomacular traction syndrome (group 2; n=50). Vitreomacular attachment was assessed during vitrectomy under the condition of continuous air infusion. In the two groups,
complete or partial vitreous attachment to the macula was observed in 57.4% and 74%, respectively. We conclude that vitreomacular
adhesion is a common feature of the two clinical situations. Visual improvement was achieved in 73% of both groups. High rates
of postoperative visual acuities of 20/50 or better (60.6% in group-1; 65.7% in group-2 cases) occurred only in eyes with
preoperative values of 20/100 or better. It is reported that the visual outcome of vitreoretinal surgery for the two clinical
conditions deteriorates with increasing duration after initial manifestation. Vitrectomy should not be postponed in patients
who complain of disturbing visual symptoms such as reduced visual acuity, metamorphopsia and disturbance of binocular reading.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
5.
Justus Schneider 《Archives of orthopaedic and trauma surgery》1940,40(4):492-494
Ohne Zusammenfassung
Mit 3 Textabbildungen 相似文献
6.
Justus Kaufman 《American journal of surgery》1945,69(1):129-132
A case of an isolated myeloma of the skull in a fourteen year old boy is recorded. The coincidence of myelogenous leukemia in the family was noted. This case was treated by a combination of surgery and x-ray and followed for a four-year period with an apparent recovery. 相似文献
7.
Perkins Jessica M. Kakuhikire Bernard Baguma Charles Rasmussen Justin D. Satinsky Emily N. Kiconco Allen Kananura Justus Audet Carolyn M. Siedner Mark J. Haberer Jessica E. Bangsberg David R. Tsai Alexander C. 《AIDS and behavior》2022,26(6):1892-1904
AIDS and Behavior - Although misperceived norms often drive personal health behaviors, we do not know about this phenomenon in the context of antiretroviral therapy (ART) adherence. We conducted a... 相似文献
8.
Biological response to phorbol ester determined by alternative G1 pathways. 总被引:4,自引:0,他引:4 下载免费PDF全文
T S Huang J Duyster J Y Wang 《Proceedings of the National Academy of Sciences of the United States of America》1995,92(11):4793-4797
A plethora of extracellular signals is known to induce a common set of immediate early genes. The immediate early response, therefore, must not be sufficient to determine the biological outcome. An example of this is found with the phorbol ester 12-O-tetradecanoylphorbol 13-acetate (TPA). A potent activator of protein kinase C, TPA can either stimulate or inhibit cell proliferation, depending on the cell type. This cell context-dependent response to TPA is observed with two subclones of NIH 3T3 cells, the P- and the N-3T3 clones. TPA is a mitogen for the P-3T3 but an antimitogen for the N-3T3 cells. The immediate early pathway is activated by TPA in both cell types, indicating that this pathway alone does not activate DNA synthesis. The delayed induction of cyclin D1 expression by TPA is observed only in the P-3T3 cells, correlating with mitogenesis. N-Acetylcysteine does not affect the immediate early pathway but can inhibit the TPA-mediated induction of cyclin D1 and DNA synthesis. In the N-3T3 cells, TPA causes an inhibition of the cyclin E-associated kinase at the G1/S transition, correlating with growth inhibition. The growth-inhibitory activity of TPA is not affected by N-acetylcysteine. Thus, the two TPA-regulated G1 pathways can be distinguished by their sensitivity to N-acetylcysteine. These results demonstrate that TPA can activate alternative G1 pathways. Moreover, the selection of the alternative G1 pathways is determined by the cell context, which, in turn, dictates the biological response to TPA. 相似文献
9.
Hübinger G Scheffrahn I Müller E Bai R Duyster J Morris SW Schrezenmeier H Bergmann L 《Experimental hematology》1999,27(12):1523-1805
The heterogenous group of anaplastic large cell lymphomas (ALCLs) is characterized by expression of the Ki-1/CD30 antigen, a member of the tumor necrosis factor receptor superfamily. About 40 to 50% of cases diagnosed as ALCL contain a specific chromosomal rearrangement, t(2;5)(p23;q35), resulting in expression of the chimeric tyrosine kinase NPM-ALK. As NPM-ALK-positive lymphomas define a distinct subtype within the group of ALCL, the chimeric protein might be responsible for certain pathogenetic and clinicopathologic characteristics. To better elucidate the function of NPM-ALK, we investigated a possible mechanism for regulation of its activity. We demonstrate that NPM-ALK specifically binds to the intracellular domain of the cytokine receptor CD30. In vitro binding assays revealed that the ALK portion of NPM-ALK mediates interaction of the two proteins. Stimulation of the CD30 receptor by cross-linking with immobilized anti-CD30 antibody results in complete growth inhibition of Karpas 299, an NPM-ALK-positive ALCL cell line, but does not alter proliferation of HDLM-2, a Hodgkin's lymphoma-derived cell line lacking t(2;5). Western blot analysis of coimmunoprecipitated CD30 and NPM-ALK proteins from stimulated Karpas 299 cells showed that the interaction of the proteins is not modified by stimulation. Activation of CD30 neither enhanced NPM-ALK activity measured by autophosphorylation of the chimeric tyrosine kinase nor phosphorylation of phospholipase C-gamma, an NPM-ALK substrate. We conclude that NPM-ALK is not stimulated by CD30 activation, but exists as a constitutively hyperactivated protein. Interaction with CD30 may extend the subcellular localization of NPM-ALK to the microenvironment of membrane-associated proteins. 相似文献
10.
Alicia N. Justus Peter R. Finn Joseph E. Steinmetz 《Alcoholism, clinical and experimental research》2001,25(10):1457-1466
BACKGROUND: Recent research suggests that a reduced P300 amplitude of the event-related potential is associated with a vulnerability to alcoholism. This study tested the hypothesis that reductions in the P300 amplitude would be associated with specific dimensions of disinhibited personality (social deviance proneness and impulsivity) and that these personality traits would mediate the association between P300 and alcohol problems in a young adult sample that varied widely in disinhibitory traits. METHODS: Alcohol problems, personality (impulsivity, social deviance, harm avoidance, and excitement seeking), and event-related potentials were measured in a sample of 190 subjects (87 men, 103 women) with a mean age of 20.7 +/- 1.9 years. RESULTS: Social deviance, impulsivity, and alcohol problems were associated with reductions in the P300, but only in male subjects. A structural model suggested that social deviance, impulsivity, and alcohol problems were all strongly related to P300 amplitude at Fz. Further analyses indicated that for male subjects, social deviance mediated the association between P300 at Fz and alcohol problems as well as the association between impulsivity and alcohol problems. CONCLUSIONS: This study suggests that reduced P300s are strongly associated with a general tendency toward antisocial, defiant, and impulsive traits, which might, in turn, increase the risk for alcohol abuse. The lack of an association between reduced P300s and personality or alcohol problems in women was unexpected and deserves further study. 相似文献