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991.
CM Hunter HP Niles J Vazquez C Kloos R Subramanyam MI Williams D Cummins PA Lenton GJ Majerus 《Oral diseases》2005,11(S1):48-50
Background: Detection of oral volatile sulfur compounds (VSC) by gas chromatography (GC) is a widely used method for evaluating breath odor. Air aspirated from the mouth is injected into the GC column for analysis. To eliminate discrepancies caused by variations in operator sampling or injection techniques, a new GC system designed to aspirate breath samples directly into the GC was developed.
Objective: A clinical study was performed to compare this new automated breath-sampling GC system to organoleptic evaluation by two trained odor judges.
Methods: A randomized, two-cell, double-blind, parallel design was used in which subjects were tested before and 3 h after using either a mouthrinse containing zinc or a matching placebo rinse. Thirteen subjects used the zinc mouthrinse, and 12 used the placebo. Subjects with a wide range of VSC levels were studied. The average organoleptic ratings for each subject at each time-point were compared with the average VSC measurements made with the GC, and Pearson product–moment correlation coefficients between the corresponding GC and organoleptic measurements were determined.
Results: The correlation between the GC and organoleptic assessment methods were highly significant ( P ≤ 0.001) for: total VSC, 0.65; H2 S, 0.63; CH3 SH, 0.61; and (CH3 )2 S, 0.46. The correlation between the two judges was also highly significant (0.823, P < 0.001).
Conclusion: These results demonstrate the utility of the automated GC method for evaluating breath odor. 相似文献
Objective: A clinical study was performed to compare this new automated breath-sampling GC system to organoleptic evaluation by two trained odor judges.
Methods: A randomized, two-cell, double-blind, parallel design was used in which subjects were tested before and 3 h after using either a mouthrinse containing zinc or a matching placebo rinse. Thirteen subjects used the zinc mouthrinse, and 12 used the placebo. Subjects with a wide range of VSC levels were studied. The average organoleptic ratings for each subject at each time-point were compared with the average VSC measurements made with the GC, and Pearson product–moment correlation coefficients between the corresponding GC and organoleptic measurements were determined.
Results: The correlation between the GC and organoleptic assessment methods were highly significant ( P ≤ 0.001) for: total VSC, 0.65; H
Conclusion: These results demonstrate the utility of the automated GC method for evaluating breath odor. 相似文献
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994.
R. Marsault S. Taddei CM Boulanger S. Illiano and PM Vanhoutte 《Fundamental & clinical pharmacology》1996,10(4):379-386
Summary— Experiments were performed to determine the subtypes of alpha-adrenoceptors involved in the contraction induced by rilmenidine in isolated canine cutaneous veins. Rings of saphenous vein (without endothelium) were suspended for the recording of isometric force in physiological salt solution. All experiments were performed in the presence of propranolol (to antagonize betaadrenoceptors), cocaine (to inhibit neuronal uptake) and hydrocortisone (to inhibit extraneuronal uptake). In the presence of rauwolscine (an alpha2 -adrenergic blocker), rilmenidine caused concentration-dependent contractions which were inhibited by prazosin (nonselective alpha1 -antagonist) and by (+)niguldipine (selective alpha1A -adrenergic antagonist), but not by (-)niguldipine. After treatment with phenoxybenzamine (to alkylate alpha1 -adrenoceptors), rilmenidine evoked contractions of the canine saphenous vein which were antagonized competitively by rauwolscine. The combination of rauwolscine and prazosin did not abolish contractions evoked by the highest concentrations of rilmenidine. Although binding experiments using 3 H-idazoxan suggested the existence of a nonadrenergic binding site (around 20% of the total binding), contractile studies failed to demonstrate their involvement in the increases in tension evoked by rilmenidine. These experiments suggest that the contractions evoked by rilmenidine in isolated canine veins are mediated by both alpha1A - and alpha2 -adrenoceptors. 相似文献
995.
A study of the educational and research priorities of registered nurses in rural Australia 总被引:2,自引:0,他引:2
Pamela F. Bell RN CM BA DipNEd PhD FCN John Daly RN BA BHSc MEd PhD MINA FCN FRCNA Esther M.L. Chang RN BAppSc MEdAdmin DipNEd PhD FCN 《Journal of advanced nursing》1997,25(4):794-800
This study set out to identify the educational and research priorities of registered nurses practising in rural and remote areas of Australia. It included two groups of participants, one which identified as rural and another which identified as remote. The findings for the rural cohort in the study are presented in this article. Research participants represented a national sample. The Delphi method was used to obtain the most reliable consensus of the nurse participants. In the final phase of the study, 13 high priorities were identified. Study findings highlight perceived needs for clinical nursing research and continuing education for nurses practising in rural Australia. 相似文献
996.
Jussara Personelle Shirley De Campos Rogerio De Oliveira Ruiz Gustavo Queiroz Ribeiro 《Aesthetic plastic surgery》1997,21(3):196-204
The authors propose a treatment to improve skin texture and to decrease thin wrinkles and creases. The treatment is based
on the use of 0.1% all-trans retinoic acid intradermic injections (with biopresence of 0.02%) combined with topic cream, immediately
followed by 340 Nm blue light skin exposure. These procedures determine the retinoic binding protein stabilization that provides
the acid intracellular penetration with its subsequent effects. An average of 10 sessions, once a week was required. 相似文献
997.
Heather D. Clark MD CM MSc † Annette M. O'Connor RN PhD † Ian D. Graham PhD †‡and George A. Wells PhD ‡ 《Health expectations》2003,6(2):110-117
Objectives To understand the factors associated with a post‐menopausal woman deciding to take hormone replacement therapy (HRT) after reviewing a decision aid (DA) and having a counselling visit with her physician as well as the factors associated with the act of taking HRT 2 months after the counselling interview. Design A secondary analysis of data collected for a randomized controlled trial evaluating two DAs. Main outcome results Although 28% of women were uncertain regarding their decision after the counselling interview, only 2.4% of women, at the assessment at 2 months, had not made a decision. The most significant factor associated with the decision to take HRT, after the physician visit, was the physician preference (OR: 62, 95% CI: 13.3, 289.7). Physician preference (OR: 78, 95% CI: 6.2, 975) remained the most significant factor for taking HRT 2 months after the counselling interview followed by low uncertainty about the decision (OR: 0.4, 95% CI: 0.2, 0.7). Conclusion Physician preference was the factor that was most associated with the woman's decision following counselling and 2 months later. Qualitative evaluation of the interview process involving the patient and physician would determine whether the patient and physician are reaching a shared decision or is the physician preference influencing the patient. 相似文献
998.
Hercília Maria Lins Rolim Santos Fernando Brederodes de Queiroz Rosa Maria Souto Maior Silene Carneiro do Nascimento Nereide Stela Santos Magalhes 《Drug development research》2006,67(5):430-437
The present study investigated the potential of Concanavalin A lectin (Con A) conjugated to liposomes (Con A‐liposomes) for targeting doxorubicin (DOX) to cells. The physicochemical properties and the cytotoxicity of DOX‐loaded Con A‐liposomes were evaluated. DOX‐loaded Con A‐liposomes were prepared by incubation of DOX‐loaded liposomes with a Con A‐SATA derivative. Lectin biological activity was monitored before and after conjugation by a hemagglutinating assay. The cytotoxicity of DOX‐loaded Con A‐liposomes was evaluated in terms of the inhibition of NCI‐H299 and HEp‐2 cell proliferation using the MTT method. The affinity of lectinized liposomes with these cells was thus assessed by evaluating the cytotoxic effect of the DOX released into cells. Stable DOX‐loaded Con A‐liposomes were obtained and their high affinity for cells was corroborated. The encapsulation of DOX into Con A‐liposomes produced an inhibition of roughly 70% of Hep‐2 cell proliferation and 50% of cell inhibition was verified on HCI‐H292. DOX in solution was able to inhibit only 20% of cell proliferation for both cell lines. Unloaded Con A‐liposomes were not cytotoxic. The encapsulation of DOX into Con A‐liposomes improves drug penetration into cells, thereby enhancing its cytotoxicity, especially in Hep‐2 cells. Drug Dev. Res. 67:430–437, 2006. © 2006 Wiley‐Liss, Inc. 相似文献
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