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The aim of this study was to examine the associations between outcome expectancies and ecstasy use in a sample of visitors of raves. The type of expectancies that people endorse were explored, as well as the differences between users and nonusers in expected outcomes of ecstasy use, and the associations between expectancies and quantity of ecstasy use within the group of users. Questionnaires were administered to 844 young visitors of 7 parties in the Netherlands, of which 543 reported to be users. Drug use on these parties was high: 65% reporting ecstasy use. Factor analyses showed 7 factors: negative consequences, enhancement, euphoria, sexiness, dancing, communication and self-insight. These factors strongly discriminated between users and nonusers. In particular those who scored high on self-insight and low on negative effects were most likely to use ecstasy. The expected outcomes of ecstasy are related to ecstasy use and patterns of use providing information for health education directed on long-term negative and positive effects of ecstasy use. Longitudinal research on random samples of visitors of raves is warranted. 相似文献
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94.
Is quercetin an alternative natural crosslinking agent to genipin for long‐term dermal scaffolds implantation? 下载免费PDF全文
Honglei Huang Rutger Ploeg Aldo R. Boccaccini Tahera Ansari 《Journal of tissue engineering and regenerative medicine》2018,12(3):e1716-e1724
As biocompatible matrices, porcine dermal scaffolds have limited application in tissue engineering due to rapid degradation following implantation. This study compared the physical, chemical and biomechanical changes that occurred when genipin and quercetin were used to crosslink dermal scaffolds and to determine whether quercetin could be used as an alternative to genipin. Physicochemical changes in the collagen were assessed using spectroscopic methods [X‐ray diffraction analysis (XRD) and nuclear magnetic resonance (NMR) analysis]. The crosslinking reaction was evaluated by quantification of amino acids and the degree of this reaction by ninhydrin assay. Because the mechanical behaviour of the collagen matrices is highly influenced by crosslinking, the tensile strength of both sets of scaffolds was evaluated. The highest mechanical strength, stiffness, degree of crosslinking and changes in the packing features of collagen (measured by XRD) were achieved using genipin. Some of the results found in the quercetin‐crosslinked scaffolds were possibly due to hydration and dehydration effects elicited by the solvents (phosphate‐buffered saline or ethanol), as seen in the NMR results. In the quercetin‐ethanol‐crosslinked scaffolds, possible reorientation of the amino groups of the collagen molecule may have taken place. Therefore, depending on their proximity to the crosslinking reagent, different types and numbers of interactions may have occurred, inducing a higher crosslinking degree (as evidenced by the ninhydrin assay) and reduction in the free amino acids after reaction. Both crosslinking agents and solvents interfere in the physicochemical properties of collagen thereby inducing variations in the matrix structure. Quercetin‐crosslinked scaffolds may have broader clinical application where a lower degree of crosslinking and stiffness is required. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
95.
Van Der Vorst H Engels RC Deković M Meeus W Vermulst AA 《Addiction (Abingdon, England)》2007,102(7):1064-1075
AIMS: To examine the bi-directional associations between providing alcohol-specific rules and adolescents' alcohol use. Further, to explore person-environment interactions, we tested whether Big Five personality traits moderate the assumed association between providing alcohol-specific rules and adolescents' alcohol use. DESIGN: Longitudinal data (three waves in 2 years) from 428 families, consisting of both parents and two adolescents (aged 13-16 years) were used for the analyses. Analyses were conducted on four samples: a group of older adolescents and a group of younger adolescents who already consumed alcohol, and a group of older and younger adolescents who were not drinking at baseline measurement. FINDINGS: In general, results of structural equation modelling showed that providing clear alcohol-specific rules lowers the likelihood of drinking initiation, regardless of the age of the youngsters. Once adolescents have established a drinking pattern, the impact of parental alcohol-specific rules declined or even disappeared. Finally, the Big Five personality traits did not moderate the association between providing alcohol-specific rules and adolescents' alcohol involvement. CONCLUSIONS: In sum, in particular during the initiation phase of drinking, parents could prevent the drinking of their offspring, regardless of the age or personality of their youngsters, by providing clear alcohol-specific rules. 相似文献
96.
Apostolos Tzikas MD Nicolo Piazza MD Bas M. van Dalen MD Carl Schultz MD PhD Marcel L. Geleijnse MD PhD Robert‐Jan van Geuns MD PhD Tjebbe W. Galema MD Rutger‐Jan Nuis MSc Amber Otten MSc Juan‐Luis Gutierrez‐Chico MD PhD Patrick W. Serruys MD PhD Peter P. de Jaegere MD PhD 《Catheterization and cardiovascular interventions》2010,75(1):43-49
Objectives : To assess the acute and intermediate changes in mitral regurgitation (MR) severity after transcatheter aortic valve implantation (TAVI) with the CoreValve Revalving SystemTM (CRS). Background : Following surgical aortic valve replacement, improvement in MR is reported in 27–82% of the patients. The changes in MR severity following CRS implantation are unknown. Methods : Transthoracic echocardiography was performed in 79 consecutive patients before and after treatment, and at the first outpatient visit. Left ventricular dimensions and ejection fraction (LVEF), left atrial (LA) size, and aortic gradient were measured. MR was assessed by color flow mapping and was graded as none, mild, moderate, or severe. It was defined as organic or functional. The depth of CRS implantation was measured by angiography. Results : Post‐treatment, the mean gradient decreased from 48 ± 16 mm Hg to 9 ± 5 mm Hg (P < 0.0001). There was no significant change in the left ventricular dimensions, LA size, and LVEF. MR pretreatment was mild, moderate, or severe in 57%, 18%, and 1% of the patients, respectively. It was defined as organic in 27 patients (36%) and functional in 27 patients (36%). The degree of MR remained unchanged in 61% of the patients, improved in 17%, and worsened in 22%. MR improvement was associated with a lower baseline LVEF (P = 0.02). There was no association between the changes in MR severity and the depth of CRS implantation. Conclusions : Most patients who underwent TAVI had some degree of MR. Overall there was no change in the degree of MR post‐treatment. Patients in whom MR improved had a lower LVEF at baseline. © 2009 Wiley‐Liss, Inc. 相似文献
97.
Poelen EA Derks EM Engels RC van Leeuwe JF Scholte RH Willemsen G Boomsma DI 《Alcoholism, clinical and experimental research》2008,32(6):975-982
Background: The present study assessed the relative contribution of genes and environment to individual differences in initiation of alcohol use and frequency of drinking among early adolescents and examined the extent to which the same genetic and environmental factors influence both individual differences in initiation of alcohol use and frequency of drinking.
Methods: Questionnaire data collected by the Netherlands Twin Register were available for 694 twin pairs aged of 12 to 15 years. Bivariate genetic model fitting analyses were conducted in mx . We modeled the variance of initiation of alcohol use and frequency of drinking as a function of three influences: genetic effects, common environmental effects, and unique environmental effects. Analyses were performed conditional on sex.
Results: Findings indicated that genetic factors were most important for variation in early initiation of alcohol use (83% explained variance in males and 70% in females). There was a small contribution of common environment (2% in males, 19% in females). In contrast, common environmental factors explained most of the variation in frequency of drinking (82% in males and females). In males the association between initiation and frequency was explained by common environmental factors influencing both phenotypes. In females, there was a large contribution of common environmental factors that influenced frequency of drinking only. There was no evidence that different genetic or common environmental factors operated in males and females.
Conclusion: Different factors were involved in individual differences in early initiation of alcohol use and frequency of drinking once adolescents have started to use alcohol. 相似文献
Methods: Questionnaire data collected by the Netherlands Twin Register were available for 694 twin pairs aged of 12 to 15 years. Bivariate genetic model fitting analyses were conducted in mx . We modeled the variance of initiation of alcohol use and frequency of drinking as a function of three influences: genetic effects, common environmental effects, and unique environmental effects. Analyses were performed conditional on sex.
Results: Findings indicated that genetic factors were most important for variation in early initiation of alcohol use (83% explained variance in males and 70% in females). There was a small contribution of common environment (2% in males, 19% in females). In contrast, common environmental factors explained most of the variation in frequency of drinking (82% in males and females). In males the association between initiation and frequency was explained by common environmental factors influencing both phenotypes. In females, there was a large contribution of common environmental factors that influenced frequency of drinking only. There was no evidence that different genetic or common environmental factors operated in males and females.
Conclusion: Different factors were involved in individual differences in early initiation of alcohol use and frequency of drinking once adolescents have started to use alcohol. 相似文献
98.
Marcelle D. Smit MSc Pascal F.H.M. Van Dessel MD PhD Wybe Nieuwland MD PhD Ans C.P. Wiesfeld MD PhD Eng S. Tan MD Rutger L. Anthonio MD PhD Lieselot Van Erven MD PhD Dirk J. Van Veldhuisen MD PhD FACC Isabelle C. Van Gelder MD PhD 《Heart rhythm》2006,3(12):1397-1403
BACKGROUND: Right ventricular (RV) pacing in implantable cardioverter-defibrillator (ICD) patients may have detrimental effects on morbidity and mortality, in particular by inducing heart failure (HF). OBJECTIVE: We investigated whether RV pacing increases the risk of HF in an asymptomatic ICD population. METHODS: We evaluated all patients without symptomatic HF who received an ICD. The primary endpoint was the occurrence of HF, which was defined as new HF, hospitalization for HF, or death due to HF. The secondary endpoint was appropriate shocks. RESULTS: The study population consisted of 456 patients with mean left ventricular ejection fraction (LVEF) 40% +/- 13%. Mean follow-up was 31 +/- 22 months. Because of the bimodal distribution of pacing, patients were divided into two groups: paced 50% (median 96%; n = 143). HF occurred more often in the paced >50% group (20% versus 9%; P <.001). Multivariate analysis identified RV pacing >50% (adjusted hazard ratio [HR] 1.85; 95% confidence interval [CI] 1.08-3.15; P = .03), baseline LVEF <26% (adjusted HR 3.15; 95% CI 1.77-5.59; P <.001), angina pectoris, history of atrial fibrillation, and baseline diuretic use as independent predictors of HF. RV pacing caused more HF events in patients with LVEF <26% (n = 64; 55% of paced >50% patients versus 20% of paced 50% also independently predicted appropriate shocks (adjusted HR 1.50; 95% CI 1.02-2.20; P = .04). CONCLUSION: RV pacing was associated with an increased risk of HF in asymptomatic ICD patients, particularly in those with preexistent left ventricular dysfunction. 相似文献
99.
Ng AC Delgado V Djaberi R Schuijf JD Boogers MJ Auger D Bertini M de Roos A van der Meer RW Lamb HJ Bax JJ 《Current problems in cardiology》2011,36(1):9-47
Diabetic heart disease is currently defined as left ventricular dysfunction that occurs independently of coronary artery disease and hypertension. Its underlying etiology is likely to be multifactorial, acting synergistically together to cause myocardial dysfunction. Multimodality cardiac imaging, such as echocardiography, nuclear, computed tomography, and magnetic resonance imaging, can provide invaluable insight into different aspects of the disease process, from imaging at the cellular level for altered myocardial metabolism to microvascular and endothelial dysfunction, autonomic neuropathy, coronary atherosclerosis, and finally, interstitial fibrosis with scar formation. Furthermore, cardiac imaging is pivotal in diagnosing diabetic heart disease. Thus, the aim of the present review is to illustrate the role of multimodality cardiac imaging in elucidating the underlying pathophysiologic mechanisms of diabetic heart disease. 相似文献
100.
van Gent R Schadenberg AW Otto SA Nievelstein RA Sieswerda GT Haas F Miedema F Tesselaar K Jansen NJ Borghans JA 《Blood》2011,118(3):627-634
Thymectomy during early childhood is generally thought to have serious consequences for the establishment of the T-cell compartment. In the present study, we investigated the composition of the T-cell pool in the first 3 decades after thymectomy during infancy due to cardiac surgery. In the first 5 years after thymectomy, naive and total CD4(+) and CD8(+) T-cell numbers in the blood and T-cell receptor excision circle (TREC) levels in CD4(+) T cells were significantly lower than in healthy age-matched controls. In the first years after thymectomy, plasma IL-7 levels were significantly elevated and peripheral T-cell proliferation levels were increased by ~ 2-fold. From 5 years after thymectomy onward, naive CD4(+) and CD8(+) T-cell counts and TRECs were within the normal range. Because TREC levels are expected to decline continuously in the absence of thymic output, we investigated whether normalization of the naive T-cell pool could be due to regeneration of thymic tissue. In the majority of individuals who had been thymectomized during infancy, thymic tissue could indeed be identified on magnetic resonance imaging scans. Whereas thymectomy has severe effects on the establishment of the naive T-cell compartment during early childhood, our data suggest that functional regrowth of thymic tissue can limit its effects in subsequent years. 相似文献