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991.
We report that erythroid-potentiating activity (EPA), known to stimulate the proliferation of normal human erythroid precursors in vitro, has a growth-promoting effect on human K562 erythroleukemia cells and Friend mouse erythroleukemia cells. Detailed studies were carried out using an EPA produced by a human T-lymphoblast line (Mo). Although EPA has not been purified to homogeneity, several observations indicate that the factor elaborated by Mo cells that stimulates erythroleukemia cell growth is the EPA molecule. The erythroleukemia growth factor cofractionates with EPA using gel exclusion chromatography, isoelectric focusing, and ion exchange chromatography. In addition, the activities exhibit similar kinetics of heat inactivation. A granulocyte-macrophage colony-stimulating factor also elaborated by Mo cells had no effect on the growth of the erythroleukemia cells. Other sources of EPA, such as peripheral blood leukocyte-conditioned medium, preparations from urine of anemic patients, and medium conditioned by a human monocyte-like cell line, stimulated erythroleukemia cell growth. Mouse sources of EPA (termed "burst-promoting activity") stimulated mouse but not human erythroleukemia cells. The availability of cell lines apparently responsive to EPA should prove useful for examining the mode of action of this regulator of erythropoiesis. 相似文献
992.
Mitus AJ; Stein R; Rappeport JM; Antin JH; Weinstein HJ; Alper CA; Smith BR 《Blood》1989,74(8):2764-2768
Serial serum protein electrophoreses were performed on 60 patients undergoing allogeneic and syngeneic bone marrow transplantation (BMT). More than 50% of patients (31 of 60) developed transient oligoclonal and monoclonal gammopathies that appeared an average of 84 days posttransplantation (range 27 to 336 days) and persisted an average of 175 days (range 14 to 652 days). Immunofixation analysis revealed 82% of the M components to be of the immunoglobulin G (IgG) type and 18% to be IgM; 56% were kappa and 44% were lambda. A strong correlation between development of graft versus host disease (GVHD) and appearance of M components was observed (73% incidence in GVHD patients v 27% in non-GVHD patients, P = .0003). Two of the three syngeneic graft recipients also developed monoclonal gammopathies. Evidence of oligoclonal circulating B-cell populations was found in 68% of patients posttransplantation by flow cytometric B-cell clonal excess assay. No correlation of recovery of particular B- or T-lymphocyte subsets and development of M components was seen. The development of transient oligoclonal and monoclonal gammopathies after transplantation may be a ubiquitous finding reflecting recapitulation of early B-cell ontogeny. 相似文献
993.
The authors compared the effectiveness of three anxiety-reducing interventions for patients undergoing magnetic resonance imaging. Each of 50 subjects was randomly assigned to one of the interventions. Intervention 1 involved provision of information about the imager and nature of the examination. Intervention 2 included information and counseling. Intervention 3 included information and a 12-minute relaxation exercise. Anxiety levels were measured by means of a 20-item questionnaire before and after imaging. The latter provided a retrospective report of anxiety experienced during imaging. Patients in intervention group 3 showed significantly less increase in anxiety compared with those in groups 1 and 2. Overall, only patients who participated in intervention 1 showed a significant increase in anxiety during imaging. When anxiety levels experienced before and during the examination were compared, with the focus on each questionnaire item for each group, those in group 1 showed a significant increase in anxiety on eight of 20 items; those in group 2, three items; and those in group 3, none. Psychologic preparation that includes relaxation strategies is more effective than provision of information alone. 相似文献
994.
Enhanced nitric oxide release during cortical spreading depression following infusion of glyceryl trinitrate in the anaesthetized cat 总被引:2,自引:0,他引:2
SJ Read MI Smith AJ Hunter AA Parsons 《Cephalalgia : an international journal of headache》1997,17(3):159-165
Intravenous infusion of glyceryl trinitrate (GTN) into migraineurs induces an immediate headache followed by migraine. We studied the effect of GTN 10.25 g kg1 min 1 ) on local cerebrovascular laser Doppler flux (rCBFLDF ), artery diameter and NO concentration (selective NO microelectrode) in the pial middle cerebral artery perfusion territory of the anaesthetized cat, at rest and during cortical spreading depression (SD). GTN infusion induced a significant increase in pial artery diameter, rCBFLDF , and NO concentration. Following termination of infusion, NO concentrations remained significantly elevated above controls for 60 min, other parameters returned to baseliae within 10 min ( p 0.05, ANOVA, post hoc Dunnett's multiple comparison procedure). Two hours after termination of infusion KCl-evoked SD was initiated. GTN-treated animals exhibited significantly ( p 0.05, Kruskal-Wallis) elevated SD-induced NO release compared to controls. All other parameters remained unaffected. Our results demonstrate that GTN induces a prolonged increase in local NO concentrations and enhances SD-induced NO release. 相似文献
995.
996.
In an attempt to reduce or eliminate homologous red blood cell transfusion requirements during allogeneic bone marrow transplantation (BMT), we instituted a novel program whereby recombinant human erythropoietin was administered to pairs of BMT donors and recipients. Eleven recipients and their HLA-matched donors were enrolled. Donors treated with recombinant human erythropoietin (rHuEPO) were phlebotomized a median of 6 U (range, 4 to 11 U) of blood over a 5-week period. This donor-derived blood was available to the BMT donor or recipient as needed. Transplant recipients were also treated with rHuEPO post-BMT to hasten erythropoiesis. Five of 11 BMT recipients underwent transplant receiving only donor-derived red blood cell transfusion, compared with 0 of 11 concomitant control recipients (P = .04). In addition, the time to absolute reticulocyte count > or = 10(4)/microL was statistically shorter in the rHuEPO-treated recipient group. This study serves as a paradigm for hematopoietic growth factor use in allogeneic BMT to decrease or eliminate homologous transfusion exposures and to possibly hasten hematopoietic engraftment. 相似文献
997.
A Bhatnagar AJ Kanwar D Parsad D De 《Journal of the European Academy of Dermatology and Venereology》2007,21(10):1381-1385
BACKGROUND: Vitiligo is a common pigmentary disorder with great cosmetic and psychological morbidity and an unpredictable course. No treatment available is a definitive cure. Systemic psoralen and ultraviolet A (PUVA) has been the mainstay of treatment. Narrow-band UVB (NBUVB) was later introduced. In this study, we have compared the phototherapy modalities PUVA and NBUVB in inducing stability in vitiligo, assessed by using vitiligo disease activity score (VIDA), for the first time. AIMS: To investigate the position of NBUVB vis-à-vis PUVA in terms of stability achieved during therapy as indicated by the VIDA scores. SUBJECTS AND METHODS: It was an open, prospective study of 50 patients divided equally in PUVA and NBUVB groups. The study period was from January 2004 to June 2005. This study was done as a part of a larger project to compare the efficacy of mentioned modalities in degree of repigmentation. RESULTS: In the NBUVB group, disease activity was present in 40% patients before commencement of therapy, which was reduced to 16% at the end of therapy (statistically significant, P = 0.049). In the PUVA group, similar figures were 20% and 16%, respectively. In the NBUVB group, 50% of patients whose disease was active prior to commencement of therapy had less than 50% repigmentation, whereas an equal number of patients had repigmentation of more than 50%. Almost an equal number of stable patients had less than and more than 50% repigmentation. In the PUVA group, 4 of the 5 (80%) patients who had active disease had less than 50% repigmentation, whereas only 1 patient (20%) with active disease obtained more than 50% repigmentation. The time to attain stability was 3.6 +/- 2.1 months in the NBUVB group and 3.22 +/- 3.1 months in the PUVA group. Eight of the 10 (80%) patients with unstable disease in the NBUVB group achieved stability, whereas 2 of the 5 (40%) patients of similar pre-treatment status in the PUVA group achieved stability. CONCLUSION: NBUVB was in a more statistically advantageous position vis-à-vis PUVA, in respect to stability achieved and efficacy in both active and stable disease in a comparable time period. 相似文献
998.
Recurrence of unexpected infant death 总被引:1,自引:0,他引:1
S. Wolkind EM Taylor AJ Waite M. Dalton JL Emery 《Acta paediatrica (Oslo, Norway : 1992)》1993,82(10):873-876
Families which had experienced two or more unexpected infant deaths were the subject of detailed confidential enquiries, including necropsy examination. Cases were derived from two main sources: first, deaths occurring during a nationwide programme of support for families with a subsequent baby (8 families) plus 2 families from a scries of confidential enquiries in Sheffield, and second, direct referrals from paediatricians (17 families). Fifty-seven deaths were studied. Twenty-four families had experienced 2 and three had experienced 3 deaths: 11 deaths (19%) were found to be adequately explained by history or post-mortem findings; 7 (12%) were probably accidental; 31 (55%) were most probably due to an action by one of the parents (filicide); only 5 (9%) were considered to be true or idiopathic sudden infant death syndrome; in 3 (5%) cases there was insufficient information to draw a conclusion. Five (18%) of the families lived in circumstances of serious social deprivation. A history of psychiatric illness was present in one or both parents in 18 (67%) of the families. 相似文献
999.
1000.