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991.
992.
The prevalence and risk factors for hepatitis delta virus (HDV) infection among Mongolian school children were assessed by detecting the antibody against HDV and HDV RNA, and through structured interviews. The study subjects consisted of 181 children with the past or ongoing hepatitis B virus infection who were investigated during the nationwide serosurvey conducted in 2004. The prevalence of antibody to HDV was 6.1%, with the proportion of 13.6% among hepatitis B surface antigen (HBsAg)-positive subjects, all of whom had HDV RNA. Multivariate logistic regression analyses showed that injections (> 11 times) (odds ratio [OR] = 8.31, 95% confidence interval [CI] = 1.28-54.07) and blood sampling (> 3 times) (OR = 5.34, 95% CI = 1.12-25.53) in health care settings, hospitalization (> 3 times) (OR = 6.20, 95% CI = 1.18-32.71), and cohabitating with patients with chronic hepatitis (OR = 4.57, 95% CI = 1.26-16.55) predicted the seropositivity for antibody to HDV. These results suggest that parenteral exposures in health care settings and household transmission are the main routes of HDV transmission among Mongolian children.  相似文献   
993.
We retrospectively surveyed the data of 233 patients who underwent myeloablative allogeneic hematopoietic stem cell transplantation (allo-HSCT) for non-Hodgkin lymphoma (NHL). Donors were HLA-matched relatives in 154 patients (66%) or unrelated volunteers in 60 (26%). Ninety patients (39%) were in complete remission. One hundred ninety-three (83%) received a total body irradiation (TBI)-based regimen, and 40 (17%) received a non-TBI-based regimen. Acute graft-versus-host disease (GVHD) occurred in 155 (67%) of the 233 evaluable patients; grade II to IV in 90 (39%), and grade III to IV in 37 (16%). Treatment-related mortality (TRM) was observed in 98 patients (42%), and 68% of them were related to GVHD. In a multivariate analysis, chemoresistance, prior autograft, and chronic GVHD were identified as adverse prognostic factors for TRM. Relapse or progression of lymphoma was observed in 21%. The 2-year overall survival rates of the patients with indolent (n = 38), aggressive (n = 111), and lymphoblastic lymphoma (n = 84) were 57%, 42%, and 41%, respectively. In a multivariate analysis, chemoresistance, prior autograft, and prior radiotherapy were identified as adverse prognostic factors for overall survival. Although myeloablative allo-HSCT represents an effective therapeutic option for patients with NHL, more work is still needed to decrease TRM and relapse.  相似文献   
994.
Shibuki K  Ono K  Hishida R  Kudoh M 《NeuroImage》2006,30(3):735-744
Aerobic energy metabolism in the brain is reflected as changes in the green fluorescence of mitochondrial flavoproteins, and the activity-dependent changes in endogenous fluorescence are applicable for functional brain imaging. To understand the roles of cortical plasticity in discrimination learning, we used flavoprotein fluorescence imaging to visualize changes of neural activities in the rat primary somatosensory cortex (SI) after learning. Rats were trained to discriminate floor vibration at rewarded and unrewarded frequencies. After this discrimination learning was accomplished in 3-5 days, the rats were anesthetized with urethane (1.5 g/kg, i.p.), and neural responses were recorded in SI during flutter stimuli applied to the contralateral hindpaw. The fluorescence responses to the stimuli at unrewarded frequencies were selectively depressed in the trained rats, which had behaviorally neglected unrewarded stimuli. The depression of cortical responses was not observed in the rats trained with rewarded stimuli only. Therefore, the stimulus-specific depression in SI might explain a part of neural mechanisms underlying discrimination behavior. To reproduce the stimulus-specific depression of cortical responses in anesthetized rats, tetanic cortical stimulation was paired with flutter stimulation applied to the hindpaw. Selective depression of fluorescence responses or field potentials in SI was induced by the paired stimulation. Our findings suggest that some intracortical circuits in SI are specifically tuned to and modulated by unrewarded stimuli of a particular frequency while SI neurons are responsive to both of rewarded and unrewarded stimuli. The present results indicate the usefulness of flavoprotein fluorescence imaging for investigating somatosensory cortical plasticity after learning.  相似文献   
995.
996.
The impact of cytomegalovirus (CMV) infection of the genital tract during pregnancy on adverse pregnancy outcomes is not understood fully. A real-time PCR assay was used to determine vaginal shedding of CMV in 993 healthy pregnant Japanese women and the results were compared with the outcome of pregnancy. CMV DNA was detected in 76 (7.7%) of the women. The outcome of pregnancy could be determined finally in 848 women, of whom 60 (7.1%) were CMV positive. The carriers of CMV had an increased miscarriage rate (RR 6.96, 95% CI 2.04-23.84, P < 0.01). These findings suggest that latent genital tract CMV infection predisposes to adverse pregnancy outcomes.  相似文献   
997.
One hundred ten consecutive patients (60 males and 50 females; age, mean +/- standard deviation [SD], 22.6 +/- 6.4 years; range 16-48 years) who were clinically diagnosed with sporadic acute hepatitis between December 2004 and January 2005 in Ulaanbaatar, Mongolia, were studied. IgM antibodies to hepatitis A virus were detected in 18 patients (16.4%), IgM antibodies to hepatitis B core (anti-HBc IgM) in 38 patients (34.5%) including two patients with concurrent hepatitis delta virus (HDV) infection, and hepatitis C virus RNA in nine patients (8.2%). There were 30 hepatitis B virus (HBV) carriers who had detectable hepatitis B surface antigen and antibodies to HDV but were negative for anti-HBc IgM, suggesting that they acquired type D acute hepatitis due to superinfection of HDV on a background of chronic HBV infection. None had IgM antibodies to hepatitis E virus (HEV). Consequently, 16.4, 32.7, 6.4, 1.8, and 27.3% of the patients were diagnosed as having acute hepatitis of type A, B, C, type B + D (HBV/HDV coinfection), and type D (superinfection of HDV), respectively. The cause of hepatitis was not known in the remaining 17 patients (15.5%). All 18 HAV isolates were genotyped as IA, all 9 HCV isolates were genotyped as 1b, and all 32 HDV isolates were classified into genotype I. The distribution of HBV genotypes among the 67 HBV isolates was A (1.5%, n = 1) and D (98.5%, n = 66). The present study indicates that de novo infections of HAV, HBV, HCV, and HDV are prevalent among young adults in Mongolia.  相似文献   
998.
BACKGROUND/AIMS: Ultrasound is noninvasive and useful to evaluate liver disease despite its operator dependency. This pilot study was conducted to quantitatively assess liver fibrosis using ultrasound. METHODS: Fibrosis extraction ratios (FER) (fiber volume/total volume) of ultrasound and histological images of 8 autopsy specimens were compared. We also compared FER of ultrasound images from clinical patients (n=79) with histological fibrosis stages. RESULTS: In the autopsy study, FER correlation coefficient between histological images and ultrasound images was 0.992. Regarding clinical patients, there was sufficient evidence to indicate differences in the distributions of FER for each fibrosis stage (Kruskal-Wallis test P<0.0001). With FER cut-off to distinguish > or =F2 from F0 and F1 defined as mean plus standard deviation of F0 and F1, sensitivity, specificity, positive predictive value, negative predictive value, and likelihood ratio were 62, 75, 78, 57%, and 2.47, respectively. Regarding HCV cohort (n=44), they were 55, 87, 89, 50%, and 4.14, respectively. Areas under receiver operating characteristic curves were 0.78, 0.79, 0.83 and 0.83 for > or =F1, > or =F2, > or =F3 and =F4, respectively. Regarding HCV cohort, they were 0.74, 0.71, 0.79 for > or =F2, > or =3 and =4, respectively. CONCLUSIONS: The FER method has great potential for diagnosing liver fibrosis using ultrasound.  相似文献   
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1000.
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