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81.
ObjectivesTo assess the role of the Val66Met polymorphism at the brain-derived neurotrophic factor (BDNF) gene on the performance of children and adolescents with bipolar disorder [juvenile bipolar disorder (JBD)] on the Wisconsin Card Sorting Test (WCST).MethodsChildren and adolescents were assessed by the K-SADS-PL and a clinical evaluation for BD and comorbid conditions. Manic and depressive symptoms were assessed with the Young Mania Rating Scale and the Children Depression Rating Scale – Reviewed. The Val66Met polymorphism at the BDNF was genotyped from a blood sample. Patients’ IQ and executive functions were assessed by a standard cognitive flexibility test (WCST).ResultsFifty-three subjects were included in the study. No significant difference was observed between the Val/Val and Val/Met+Met/Met groups on any WCST scores in the MANCOVA (F48,5 = .76; p = .59; Perseverative Errors, p = .66; Nonperseverative Errors, p = .58; Categories Completed, p = .34; Attempts to Reach First Category, p=.64; and Percentage of Conceptual Level Responses, p = .99).ConclusionsOur findings from this sample of children and adolescents with BD do not replicate results from studies of adults and suggest the existence of differences in the neurobiology of this disorder across the life cycle. Investigations of larger samples are necessary to confirm these data.  相似文献   
82.
BackgroundA growing body of findings illustrates the importance of state-dependency in studies using brain stimulation.ObjectiveWe aimed to investigate the effects of tDCS priming followed by rTMS applied over the right dorsolateral prefrontal cortex (DLPFC) on emotional working memory.MethodsIn a randomized single-blind within-subjects design, participants performed an emotional 3-back task at baseline and after tDCS priming (anodal, cathodal) and subsequent low-frequency rTMS (active, sham) of the right DLPFC. Stimuli consisted of words related to the distinct emotion categories fear and anger as well as neutral words.ResultsTask accuracy increased for fear-related words and decreased for neutral words across stimulation conditions. No general state-dependent effects of prefrontal rTMS on working memory were found. We further showed a detrimental effect of negative emotional content on working memory performance.ConclusionsOur findings support a hemispheric lateralization of emotion processing by demonstrating that the withdrawal-related emotion fear is associated with the right DLPFC and contribute to clarifying the interaction between working memory and emotion.  相似文献   
83.

OBJECTIVE:

This study sought to evaluate the prevalence of human papillomavirus (HPV) types 16 and 18 in women with clinical stage IB cervical cancer treated by radical hysterectomy with pelvic lymphadenectomy as well as to establish a correlation between HPV type and cancer prognosis.

METHODS:

A single-center cohort study was conducted with 86 patients who had undergone radical hysterectomy for stage I cervical cancer. Prognostic factors and the presence of HPV 16 and 18 were analyzed using a polymerase chain reaction assay. A univariate analysis using Kaplan-Meier curves was conducted to estimate survival.

RESULTS:

The prevalence of HPV 16 in the study group was 65.3%, and the prevalence of HPV 18 was 33.3%. The prevalence of infection with both viruses was 26.9%. Overall survival at 5 years was 91% among women with HPV 18 and 96% among those without this virus type (p = 0.133). Among the women with HPV 16, the overall survival was 94%, whereas this rate was 96% among those without this virus type (p = 0.663). Disease-free survival was unaffected by the presence of HPV type 16 or 18.

CONCLUSION:

In the present study, despite the high prevalence of HPV types 16 and 18, the presence of these virus types did not affect the prognosis of patients with stage I cervical cancer who underwent radical hysterectomy.  相似文献   
84.

OBJECTIVE:

The audibility thresholds for the sound frequency of 137 upward- and downward-sloping audiograms showing sensorineural hearing loss were selected and analyzed in conjunction with speech recognition thresholds obtained from individuals seen at a public otolaryngology clinic to determine which frequencies in slope audiograms best represent speech recognition thresholds.

METHOD:

The linear regression model and mean square error were used to determine the associations between the threshold values.

RESULT:

The mean square error identified larger errors when using thresholds of 500, 1000, and 2000 Hz than when using audibility thresholds of 500, 1000, 2000, and 4000 Hz. The linear regression model showed a higher correlation (91%) between the audiogram thresholds for frequencies of 500, 1000, 2000, and 4000 Hz than for the frequencies of 500, 1000, and 2000 Hz (88%).

CONCLUSION:

Frequencies of 500, 1000, 2000, and 4000 Hz were the most significant in predicting the speech recognition threshold.  相似文献   
85.

OBJECTIVE:

The objective of this study was to investigate the associations between phase angle, anthropometric measurements, and lipid profile in patients chronically infected with the hepatitis C virus.

METHODS:

A total of 160 consecutive patients chronically infected with the hepatitis C virus and who received treatment at the hepatitis C outpatient unit of our hospital from April 2010 to May 2011 were prospectively evaluated. Bioelectrical impedance analysis, anthropometric measurements, and serum lipid profile analysis were performed.

RESULTS:

Twenty-five patients were excluded. A total of 135 patients with a mean age of 49.8±11.4 years were studied. Among these patients, 60% were male. The phase angle and BMI means were 6.5±0.8° and 26.5±4.8 kg/m2, respectively. Regarding anthropometric variables, mid-arm circumference, mid-arm muscle circumference, and arm muscle area had a positive correlation with phase angle. In contrast, when analyzing the lipid profile, only HDL was inversely correlated with phase angle. However, in multiple regression models adjusted for age and gender, only mid-arm circumference (p = 0.005), mid-arm muscle circumference (p = 0.003), and arm muscle circumference (p = 0.001) were associated with phase angle in hepatitis C virus-infected patients.

CONCLUSIONS:

In conclusion, phase angle is positively correlated with anthropometric measures in our study. However, there is no association between phase angle and lipid profile in these patients. Our results suggest that phase angle is related to lean body mass in patients chronically infected with hepatitis C virus.  相似文献   
86.
87.
The combined use of silane and solvated bonding agents on the bond strength to glass‐fibre posts was investigated. A model Bis‐GMA/HEMA adhesive was formulated with no solvent, 30% of ethanol or 80% of acetone. The surfaces of rectangular‐shaped posts were silanated or not and one of the agents was applied, except for the control group. Cylinders of resin cement (RelyX ARC, 3M ESPE, Saint Paul, MN, USA) were built‐up on the surfaces (n = 20) and submitted to shear testing. All groups showed higher bond strengths when the surfaces were silanated. When no silanization was carried out, the use of bonding agents, either solvated or non‐solvated, increased the bond strengths. All groups treated with both silane and bonding agent showed higher bond strengths than the group that was only silanated. Control and ethanol‐based adhesives were similar, whereas the acetone‐based agent yielded higher bond strengths. Adhesive failures were predominant. Combination of silane and adhesive enhanced the bond to fibre posts.  相似文献   
88.
Few reports have addressed the effects of diode laser irradiation at 980 nm on the morphology and fracture resistance of dentine. The purpose of this study is to evaluate the effects of 980-nm diode laser on the ultrastructure and fracture resistance of root dentine. The roots of 90 extracted canine teeth were divided into three groups according to the type of irrigating solution (water, NaOCl, and NaOCl/EDTA) and subdivided into three subgroups (n?=?10) according to the amount of laser irradiation (without irradiation, 1.5 W/100 Hz and 3.0 W/100 Hz). The roots were filled with an epoxy resin-based sealer and gutta-percha and then subjected to a fracture resistance test. Data were analyzed by ANOVA and the Tukey test (p?<?0.05). Additionally, 18 canine teeth were prepared using the same irrigation/irradiation protocols and evaluated by scanning electron microscopy (SEM). The SEM showed greater changes when the laser power increased, and the changes also varied according to the irrigating solution. A modified smear layer was observed in specimens that were treated with water and then laser-irradiated. The laser treatment did not alter the fracture resistance of roots treated with 1.5 W/100 Hz (246.3?±?29.5 N) and 3.0 W/100 Hz (215.3?±?25.1 N) laser power. The roots treated with NaOCl were more susceptible to fracture (199.4?±?15.1 N) than those irrigated with water (254.2?±?23.0 N) (p?<?0.05). The 980-nm diode laser altered the morphology of the dentine but did not affect the fracture resistance of the roots.  相似文献   
89.
Abstract Recent studies suggest that GB virus C/hepatitis G virus (GBV-C/HGV) infection in HIV-positive individuals is associated with a slower progression to AIDS, leading to a lower HIV viral load and higher counts of CD4(+) T cells, although many studies have failed to demonstrate these beneficial effects. We developed a Real-Time PCR (TaqMan RT qPCR) to quantify the viral load of GBV-C/HGV in 102 HIV-1-infected patients, who were also evaluated for the presence of anti-E2. The prevalence of GBV-C/HGV infection was 21% among infected patients and the mean plasma viral load was 3.62±0.64 log(10) copies/ml. Despite the high prevalence, there was no statistical difference when we compared the mean viral load (p≤0.46) and the average count of CD4(+) (p≤0.29) and CD8(+) (p≤0.64) among patients infected by GBV-C/HGV and HIV and patients infected only by HIV. This fact can be explained by the number of patients included in the study. Nevertheless, compared to other studies, we observed a discrete number of patients with undetectable HIV load and lower median viral load in the group presenting GBV-C/HGV RNA. Our study suggests that there may be an impact on HIV viral load in GBV-C/HGV-coinfected patients. However, further studies are needed to elucidate the molecular and cellular mechanisms involved in this viral interaction, previously reported in other studies, with the aim of contributing to the development of new targets for drugs against HIV.  相似文献   
90.
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