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101.
The achievement gap in science begins in elementary school, where many students lose interest in science-related studies, particularly students from traditionally underrepresented groups. The "My Health My World" Project (hereafter, "the Project"), developed at Baylor College of Medicine with the assistance of federal funds, is a national effort to address this problem. The Project's goals are to make science appealing and relevant for elementary school students (i.e., kindergarten through grade five), including those from underrepresented minorities (URMs), and easy to teach for teachers and parents. It is achieving this goal by the development of interdisciplinary instructional materials that use environmental health issues as a unifying theme. The Project provides its materials (including take-home materials for parents) and training for teachers at seven dissemination centers across the country, established in 1997. Workshops are also held to train facilitators, chosen from among local science education leaders, who in turn hold workshops to train other teachers. Each center receives a mini-grant to cover costs related to the training it provides, and all coordinate their training to offer comparable experiences for all participants. Field tests in 1995, 1996, and 1997 involving culturally, racially, and ethnically diverse students and teachers in two sites indicate that the participating teachers found that the Project's materials promote science learning and enthusiasm for science and are easy to use and engaging for teachers. Ratings for workshops in 1998 were also high for all characteristics evaluated. All signs after the Project's first full year of dissemination activities (1998) indicate that it will continue to reach more teachers and students across the nation and will eventually help more students from all backgrounds achieve in science-related studies. 相似文献
102.
CT evaluation of gastric wall pathology 总被引:4,自引:0,他引:4
Merino S Saiz A Moreno MJ Parlorio E Pedrosa I Yus M 《The British journal of radiology》1999,72(863):1124-1131
The purpose of this study is to show the CT features of common and infrequent pathological lesions of the gastric wall. Although CT features are not often specific, familiarity with the most frequent pathological gastric findings on CT can assist in differential diagnosis. 相似文献
103.
Pons JM Borras JM Espinas JA Moreno V Cardona M Granados A 《The Annals of thoracic surgery》1999,67(3):635-640
BACKGROUND: The aim of this study was to compare the predictive accuracy for open heart surgical mortality between a statistical model based on collection of clinical data and surgeons' subjective risk assessment. METHODS: Predictive discrimination of both risk assessments (surgeons' and model) was compared through the area under the receiver operating characteristic curve. Logistic regression analysis was used to assess the relation between surgeons' and model predictions to actual outcomes. Calibration of the subjective estimates was evaluated with a chi2 test. RESULTS: Overall, the area under the receiver operating characteristic curve was 0.76 for the statistical model and 0.70 for the subjective assessment. Logistic regression analysis showed that the statistical model remained significant after accounting for the subjective assessment. Calibration of subjective mortality predictions was poor. CONCLUSIONS: Surgeons' risk assessment tends to cluster in the middle ranges of risk. Subjective assessment seems accurate in identifying the two extremes of risk but is inaccurate for intermediate risk levels. A multivariate statistical model improves the accuracy of subjective predictions. 相似文献
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106.
Proton magnetic resonance spectroscopy pattern of progressive multifocal leukoencephalopathy in AIDS 总被引:3,自引:0,他引:3 下载免费PDF全文
Iranzo A Moreno A Pujol J Martí-Fàbregas J Domingo P Molet J Ris J Cadafalch J 《Journal of neurology, neurosurgery, and psychiatry》1999,66(4):520-523
The objective was to determine whether the use of intermediate echo times (135 ms) in proton magnetic resonance spectroscopy (1H-MRS) detects a homogenous pattern in progressive multifocal leukoencephalopathy (PML) in HIV-1 infected people, and to confirm the results of previous studies. Six patients infected with HIV-1, with PML established by biopsy, and six healthy age and sex matched volunteers were evaluated to define their spectroscopic pattern. 1H-MRS spectra performed at 1.5 T were obtained with the STEAM sequence: TE/TM/TR, 20 ms/13.7 ms/2000 ms; 2500 Hz, size 2048 points, 256 acquisitions (STEAM-20) and with the PRESS sequence; TE/TR, 135 ms/2000 ms; 2500 Hz, size 2048 points, 256 acquisitions (PRESS-135). A single voxel was placed on the lesions and on the parieto-occipital white matter of controls. The peaks of N-acetylaspartate (NAA), choline (Cho), myoinositol (mI), lactate, and lipids were considered, and the results were expressed using creatine as reference. Spectra of PML lesions were characterised by significantly reduced NAA, lactate presence, and by significantly increased Cho and lipids compared with control group values. These results indicate that 1H-MRS detects a homogenous pattern in PML lesions. Recent studies, together with this, suggest that 1H-MRS may help in the diagnostic approach to patients with suspected PML lesions associated with AIDS. 相似文献
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109.
Specific prognostic factors for secondary pancreatic infection in severe acute pancreatitis 总被引:1,自引:0,他引:1
Armengol-Carrasco M Oller B Escudero LE Roca J Gener J Rodríguez N del Moral P Moreno P 《Digestive surgery》1999,16(2):125-129
BACKGROUND/AIMS: The aim of the present study was to investigate whether there are specific prognostic factors to predict the development of secondary pancreatic infection (SPI) in severe acute pancreatitis in order to perform a computed tomography-fine needle aspiration with bacteriological sampling at the right moment and confirm the diagnosis. METHODS: Twenty-five clinical and laboratory parameters were determined sequentially in 150 patients with severe acute pancreatitis (SAP) and univariate, and multivariate regression analyses were done looking for correlation with the development of SPI. RESULTS: Only APACHE II score and C-reactive protein levels were related to the development of SPI in the multivariate analysis. A regression equation was designed using these two parameters, and empiric cut-off points defined the subgroup of patients at high risk of developing secondary pancreatic infection. CONCLUSION: The results showed that it is possible to predict SPI during SAP allowing bacteriological confirmation and early treatment of this severe condition. 相似文献
110.
Fabio Parazzini Moreno Dindelli Carlo La Vecchia Paola Liati 《Sozial- und Pr?ventivmedizin》1991,36(1):46-48
Summary The prevalence of smoking in pregnancy was analyzed in a survey of women delivering between January and March 1989 in a large maternity clinic in Milan, Northern Italy. Out of the 528 women interviewed, 183 (35%) were current smokers before pregnancy and 99 stopped smoking during pregnancy. The probability of stopping smoking decreased with increasing age and was lower in less educated women, but these findings were not statistically significant. Considering persistent smokers only, the mean number of cigarettes per day fell from 13 before to 8 during pregnancy; this reduction was generally consistent in various subgroups of age and education. The reductions, however, are probably overestimated, since they are based on the women's reports only. Thus, there still appears to be ample scope for intervention on smoking in pregnancy, particularly in older and less educated women.
Zusammenfassung Die Rauchprävalenz während der Schwangerschaft wurde in einer Querschnittstudie bei Frauen untersucht, welche zwischen Januar und März 1989 in einer grossen Frauenklinik in Mailand ein Kind zur Welt brachten. Von 528 befragten Frauen hatten 183 (35%) vor der Schwangerschaft geraucht, und 99 Frauen war es gelungen, während der Schwangerschaft mit Rauchen aufzuhören. Die Wahrscheinlichkeit für letzteres nahm mit zunehmendem Alter ab und war kleiner für Frauen mit geringer Ausbildung (statistisch nicht signifikant). Bei den Raucherinnen wurde eine Reduktion der mittleren Anzahl Zigaretten von 13 Stück vor der Schwangerschaft auf 8 während der Schwangerschaft festgestellt. Diese Reduktion fand sich in allen Alters- und Ausbildungsgruppen. Wahrscheinlich wurde die Reduktion aber überbewertet, weil sich ihre Berechnung nur auf die Aussagen der Frauen abstützte. Für Gesundheitsaktionen, die ein Rauchstopp während der Schwangerschaft zum Ziele haben, besteht immer noch ein grosser Bedarf, besonders bei älteren und weniger ausgebildeten Frauen.
Résumé La prévalence du tabagisme durant la grossese a été étudiée lors d'une enquête des parturientes entre janvier et mars 1989 dans une grande maternité de Milan. Parmi les 528 femmes interrogées, 183 (35%) étaient tabagiques avant la grossesse et 99 avaient arrêté de fumer durant la grossesse. La probalité de cesser l'habitude diminue lorsque l'âge augmente, et est basse chez les femmes dont le niveau d'éducation est bas, sans significantion statistique. En considérant uniquement les parturientes tabagiques, le nombre quotidien de cigarettes fumées passe de 13 avant la grossesse à 8 durant la grossesse; cette diminution se retrouve dans tous les groupes d'âge et tous les niveaux d'éducation. Ces diminutions sont probablement surestimées, puisqu'elles sont basées sur les seules déclarations des parturientes. Cette enquête montre qu'il existe encore une large place por la prévention.相似文献