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21.
C. Mueller-Eckhardt W. Kayser Christa Frster Gertrud Mueller-Eckhardt C. Ringenberg 《Vox sanguinis》1982,43(2):76-81
A technique is described which permits the detection of platelet-specific, noncomplement-fixing ("blocking') PlA1 antibodies in serologically negative sera of mothers from children suffering from neonatal alloimmune thrombocytopenia. The technique consists of (1) antibody enrichment in eluates prepared from maternal serum and PlA1-positive platelets, and (2) quantitation of antibodies in eluates by the platelet radioactive anti-IgG test. With this assay, PlA1 antibodies were demonstrated in 6 out of 7 maternal sera, and anti-A antibodies in one. It proved valuable also for longitudinal studies for periods up to 30 months after delivery. 相似文献
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Marzena Karcz-Kubicha Katerina Antoniou Anton Terasmaa Davide Quarta Marcello Solinas Zuzana Justinova Antonella Pezzola Rosaria Reggio Christa E Müller Kjell Fuxe Steven R Goldberg Patrizia Popoli Sergi Ferré 《Neuropsychopharmacology》2003,28(7):1281-1291
The involvement of adenosine A(1) and A(2A) receptors in the motor effects of caffeine is still a matter of debate. In the present study, counteraction of the motor-depressant effects of the selective A(1) receptor agonist CPA and the A(2A) receptor agonist CGS 21680 by caffeine, the selective A(1) receptor antagonist CPT, and the A(2A) receptor antagonist MSX-3 was compared. CPT and MSX-3 produced motor activation at the same doses that selectively counteracted motor depression induced by CPA and CGS 21680, respectively. Caffeine also counteracted motor depression induced by CPA and CGS 21680 at doses that produced motor activation. However, caffeine was less effective than CPT at counteracting CPA and even less effective than MSX-3 at counteracting CGS 21680. On the other hand, when administered alone in habituated animals, caffeine produced stronger motor activation than CPT or MSX-3. An additive effect on motor activation was obtained when CPT and MSX-3 were coadministered. Altogether, these results suggest that the motor-activating effects of acutely administered caffeine in rats involve the central blockade of both A(1) and A(2A) receptors. Chronic exposure to caffeine in the drinking water (1.0 mg/ml) resulted in tolerance to the motor effects of an acute administration of caffeine, lack of tolerance to amphetamine, apparent tolerance to MSX-3 (shift to the left of its 'bell-shaped' dose-response curve), and true cross-tolerance to CPT. The present results suggest that development of tolerance to the effects of A(1) receptor blockade might be mostly responsible for the tolerance to the motor-activating effects of caffeine and that the residual motor-activating effects of caffeine in tolerant individuals might be mostly because of A(2A) receptor blockade. 相似文献
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Torsten Haferlach Claudia Schoch Helmut L?ffler Winfried Gassmann Wolfgang Kern Susanne Schnittger Christa Fonatsch Wolf-Dieter Ludwig Christian Wuchter Brigitte Schlegelberger Peter Staib Albrecht Reichle Uschi Kubica Hartmut Eimermacher Leopold Balleisen Andreas Grüneisen Detlef Haase Carlo Aul Jochen Karow Eva Lengfelder Bernhard W?rmann Achim Heinecke Maria Cristina Sauerland Thomas Büchner Wolfgang Hiddemann 《Journal of clinical oncology》2003,21(2):256-265
PURPOSE: On the basis of cytomorphology according to the French-American-British (FAB) classification, we evaluated the prognostic impact of dysplastic features and other parameters in de novo acute myeloid leukemia (AML). We also assessed the clinical significance of the recently introduced World Health Organization (WHO) classification for AML, which proposed dysplasia as a new parameter for classification. PATIENTS AND METHODS: We analyzed prospectively 614 patients with de novo AML, all of whom were diagnosed by central morphologic analysis and treated within the German AML Cooperative Group (AMLCG)-92 or the AMLCG-acute promyalocytic leukemia study. RESULTS: Patients with AML M3, M3v, or M4eo demonstrated a better outcome compared with all other FAB subtypes (P <.001); no prognostic difference was observed among other FAB subtypes. The presence or absence of dysplasia failed to demonstrate prognostic relevance. Other prognostic markers, such as age, cytogenetics, presence of Auer rods, and lactate dehydrogenase (LDH) level at diagnosis, all showed significant impact on overall and event-free survival in univariate analyses (P <.001 for all parameters tested). However, in a multivariate analysis, only cytogenetics (unfavorable or favorable), age, and high LDH maintained their prognostic impact. Dysplasia was not found to be an independent prognostic parameter, but the detection of trilineage dysplasia correlated with unfavorable cytogenetics. CONCLUSION: Our results indicate that cytomorphology and classification according to FAB criteria are still necessary for the diagnosis of AML but have no relevance for prognosis in addition to cytogenetics. Our results suggest that the WHO classification should be further developed by using cytogenetics as the main determinant of biology. Dysplastic features, in particular, have no additional impact on predicting prognosis when cytogenetics are taken into account. 相似文献
24.
Frequency and Correlates of Substance Use among Preadolescents and Adolescents in a Swiss Epidemiological Study 总被引:1,自引:0,他引:1
Hans-Christoph Steinhausen & Christa Winkler Metzke 《Journal of child psychology and psychiatry, and allied disciplines》1998,39(3):387-397
Alcohol use and nicotine use were investigated in a representative sample of 1110 study participants aged 10 to 17 years. In addition to questions on substance use, the participants responded to questionnaires covering behavior and emotions, life events, self-related cognitions, coping capacities, perceived parental behavior, perceived school environment, and the social network. The gender gap in substance use tended to close with increasing age. Parental substance use served as a model for substance use in the participants. Substance users had more abnormal scores on almost all variables as compared to abstaining controls. Lack of acceptance and control, pressure to achieve at school, and life events significantly predicted substance use. The latter served as a moderating risk variable for delinquent behavior under stress. 相似文献
25.
Does early exposure to caffeine promote smoking and alcohol use behavior? A prospective analysis of middle school students 下载免费PDF全文
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Florida has the second highest number of newly diagnosed cases of HIV in the United States. Sociodemographic representation that is reflective of the population is essential in developing evidence based interventions to improve HIV outcomes and reduce disparities. Understanding HIV research trial participation, preferences for types of research, and fair compensation for research will further our understanding of someone’s decision to participate in research. The purpose of this analysis was to identify differences in prior research participation, trust, interests in types of research, and fair compensation between people living with HIV and without HIV in North Central Florida. In this sample of 8340 people interviewed in the community about their health concerns and research participation, 156 reported living with HIV. Only 20.5% of people with HIV reported past participation in research, however 94.2% said they were interested in future research participation. While people with HIV were slightly more interested in higher risk/low convenience research, there were no statistically significant differences in preferences for types of research between those with and without HIV. People with HIV reported no difference in the amount they would request for fair compensation ($78.4 USD) compared with those without HIV ($72.2 USD, p?=?0.69). Community members are interested in participating in research, although few had previously participated. Improving our understanding of research study participation will help improve recruitment efforts and draw stronger conclusions regarding the effectiveness of interventions, as well as enhance implementation of these interventions. 相似文献
28.
Tissue engineering is a promising potential candidate for treating intestinal failure resulting from necrotizing enterocolitis. This requires the acquisition, preparation and implantation of autologous organoid units. This may be affected by the complexities of periods of storage of viable donor tissue and delayed implantation. This chapter addresses the development, methodology, and application of tissue-engineered intestine in the experimental and clinical setting. Tissue engineering has the potential of avoiding the inherent toxicities of intestinal transplantation and prolonged immunosuppression. 相似文献
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