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991.
J Y Chai N Y Kim S M Guk Y K Park M Seo E T Han S H Lee 《The American journal of tropical medicine and hygiene》2001,65(5):518-522
The prevalence of Cryptosporidium parvum infection and its seasonality were studied in a small rural village occupied predominantly by aged people in Hwasun-gun, Chollanam-do, Republic of Korea. Fecal samples were collected monthly from November 1996 to October 1997 and examined for enteric parasites. To detect oocysts of C. parvum, the modified acid-fast stain was applied. To determine effects of climatic factors, local weather reports were collected. The overall oocyst prevalence during 1 year was 57.0% (77 of 135), and was significantly higher (P < 0.0001) in aged people--those aged 50-59 years (80.0%) and those aged 60-69 years (69.0%)--than in younger groups. No significant difference (P > 0.05) was noted between men and boys (53.6%) and women and girls (59.5%), but significant (P < 0.05) household clustering was recognized. People aged > 50 years tended to be more repeatedly positive than people in the younger group. The rate varied monthly from 7.8 to 20.0% (average, 12.6%), with significantly higher (P < 0.05) rates in spring than in summer and winter months. This seasonality had little relation with temperature (r = 0.04), but a weak correlation was found with rainfall (r = 0.4). It is of special interest that cryptosporidiosis is highly endemic among the aged population. 相似文献
992.
Young Joon Hong Myung Ho Jeong Sun Ho Hwang Nam Sik Yun Sang Rok Lee Seo Na Hong Kye Hun Kim Hyung Wook Park Ju Han Kim Youngkeun Ahn Jeong Gwan Cho Jong Chun Park Jung Chaee Kang 《Circulation journal》2006,70(10):1269-1274
BACKGROUND: This study assessed the effects of combination therapy with simvastatin and carvedilol on clinical outcome in patients with left ventricular (LV) dysfunction after acute myocardial infarction (AMI). METHODS AND RESULTS: The study retrospectively analyzed the data from 672 patients with LV dysfunction [LV ejection fraction (LVEF) <40%] complicated with AMI who underwent percutaneous coronary intervention (PCI). The patients were divided into 4 treatment groups: combination group (n=160), simvastatin only group (n=216), carvedilol only group (n=242), neither treatment group (n=54). At 6 months after PCI, the LVEF had improved most significantly in the combination group. During 1-year follow-up, cardiac death occurred most frequently in the neither treatment group compared with the other 3 groups (combination: 4%, simvastatin alone: 7%, carvedilol alone: 8%, neither: 17%, p<0.001 between neither treatment and other 3 groups). The results on major adverse cardiovascular events (MACE) showed that the combination of simvastatin and carvedilol was associated with a relative risk reduction of 53% (p<0.001), treatment with simvastatin alone with a relative risk reduction of 44% (p=0.001), and carvedilol alone with a relative risk reduction of 40% (p=0.003) compared with neither treatment. The independent predictors of 1-year MACE were neither treatment, elevated high sensitivity C-reactive protein (> or =0.5 mg/dl), and old age (>70 years). CONCLUSION: Combination therapy with simvastatin and carvedilol had a positive impact on the endpoints of cardiovascular death and MACE and seems to have an additive beneficial effect on these endpoints in patients with LV dysfunction complicated with AMI who underwent PCI. 相似文献
993.
994.
Lee NK Kim S Kim GH Heo J Seo HI Kim TU Kang DH 《Journal of magnetic resonance imaging : JMRI》2012,35(3):678-685
Purpose:
To identify MRI biomarkers that could be used to follow disease progression and therapeutic efficacy in one individual muscle in patients with myotonic dystrophy type 1 (DM1).Materials and Methods:
Lower limb MRI and maximal ankle dorsiflexor strength assessment, using a hand‐held dynamometer, were performed in 19 DM1 patients and 6 control subjects. The volume of residual muscle tissue of Tibialis Anterior (TA) muscle was chosen as an index for muscle atrophy, and the T2‐relaxation‐time of the residual muscle tissue was measured to evaluate edema‐like lesions. The fat‐to‐water ratio was assessed using three‐point Dixon images to quantify fat infiltration in the entire muscle.Results:
The intra‐observer variability of MRI indices (~5.2% for the residual muscle tissue volume and 2.5% for the fat‐to‐water ratio) was lower than that of the dorsiflexor torque measurement (~11.5%). A high correlation (r = 0.91) was found between maximal ankle dorsiflexor strength and residual TA muscle tissue volume in DM1 patients. Increases in the fat‐to‐water ratio and T2‐relaxation‐time were associated with a decrease in maximal ankle dorsiflexor strength.Conclusion:
MRI appears as a noninvasive method which can be used to follow disease progression and therapeutic efficacy. J. Magn. Reson. Imaging 2012;35:678‐685. © 2011 Wiley Periodicals, Inc. 相似文献995.
Sungjun Kim Kyung Seo Ho-Taek Song Jin-Suck Suh Choon-Sik Yoon Jeong Ah Ryu Jeong Seon Park Ah Hyun Kim Ah Young Park Yaena Kim 《Korean journal of radiology》2012,13(5):602-609
Objective
To determine which mode of ultrasonography (US), among the conventional, spatial compound, and tissue-harmonic methods, exhibits the best performance for the detection of Implanon® with respect to generation of posterior acoustic shadowing (PAS).Materials and Methods
A total of 21 patients, referred for localization of impalpable Implanon®, underwent US, using the three modes with default settings (i.e., wide focal zone). Representative transverse images of the rods, according to each mode for all patients, were obtained. The resulting 63 images were reviewed by four observers. The observers provided a confidence score for the presence of PAS, using a five-point scale ranging from 1 (definitely absent) to 5 (definitely present), with scores of 4 or 5 for PAS being considered as detection. The average scores of PAS, obtained from the three different modes for each observer, were compared using one-way repeated measure ANOVA. The detection rates were compared using a weighted least square method.Results
Statistically, the tissue harmonic mode was significantly superior to the other two modes, when comparing the average scores of PAS for all observers (p < 0.00-1). The detection rate was also highest for the tissue harmonic mode (p < 0.001).Conclusion
Tissue harmonic mode in uS appears to be the most suitable in detecting subdermal contraceptive implant rods. 相似文献996.
Hye Jeon Hwang Joon Beom Seo Jin Seong Lee Jae-Woo Song Song Soo Kim Hyun Joo Lee Chae Hun Lim 《Korean journal of radiology》2012,13(6):711-719
Objective
To determine whether the image quality (IQ) is improved with iterative reconstruction in image space (IRIS), and whether IRIS can be used for radiation reduction in chest CT.Materials and Methods
Standard dose chest CT (SDCT) in 50 patients and low dose chest CT (LDCT) in another 50 patients were performed, using a dual-source CT, with 120 kVp and same reference mAs (50 mAs for SDCT and 25 mAs for LDCT) employed to both tubes by modifying a dual-energy scan mode. Full-dose data were obtained by combining the data from both tubes and half-dose data were separated from a single tube. These were reconstructed by using a filtered back projection (FBP) and IRIS: full-dose FBP (F-FBP); full-dose IRIS (F-IRIS); half-dose FBP (H-FBP) and half-dose IRIS (H-IRIS). Objective noise was measured. The subjective IQ was evaluated by radiologists for the followings: noise, contrast and sharpness of mediastinum and lung.Results
Objective noise was significantly lower in H-IRIS than in F-FBP (p < 0.01). In both SDCT and LDCT, the IQ scores were highest in F-IRIS, followed by F-FBP, H-IRIS and H-FBP, except those for sharpness of mediastinum, which tended to be higher in FBP. When comparing CT images between the same dose and different reconstruction (F-IRIS/F-FBP and H-IRIS/H-FBP) algorithms, scores tended to be higher in IRIS than in FBP, being more distinct in half-dose images. However, despite the use of IRIS, the scores were lower in H-IRIS than in F-FBP.Conclusion
IRIS generally helps improve the IQ, being more distinct at the reduced radiation. However, reduced radiation by half results in IQ decrease even when using IRIS in chest CT. 相似文献997.
Yoo Na Kim Ho Yun Lee Kyung Soo Lee Joon Beom Seo Myung Jin Chung Myung-Ju Ahn Keunchil Park Tae Sung Kim Chin A Yi 《Korean journal of radiology》2012,13(6):702-710
Objective
To evaluate tumor responses in patients treated with anti-angiogenic agents for non-small cell lung cancer (NSCLC) by assessing intratumoral changes using a dual-energy CT (DECT) (based on Choi''s criteria) and to compare it to traditional Response Evaluation Criteria in Solid Tumors (RECIST) criteria.Materials and Methods
Ten NSCLC patients treated with bevacizumab underwent DECT. Tumor responses to anti-angiogenic therapy were assessed and compared with the baseline CT results using both RECIST (size changes only) and Choi''s criteria (reflecting net tumor enhancement). Kappa statistics was used to evaluate agreements between tumor responses assessed by RECIST and Choi''s criteria.Results
The weighted κ value for the comparison of tumor responses between the RECIST and Choi''s criteria was 0.72. Of 31 target lesions (21 solid nodules, 8 lymph nodes, and two ground-glass opacity nodules [GGNs]), five lesions (16%) showed discordant responses between RECIST and Choi''s criteria. Iodine-enhanced images allowed for a distinction between tumor enhancement and hemorrhagic response (detected in 14% [4 of 29, excluding GGNs] of target lesions on virtual nonenhanced images).Conclusion
DECT may serve as a useful tool for response evaluation after anti-angiogenic treatment in NSCLC patients by providing information on the net enhancement of target lesions without obtaining non-enhanced images. 相似文献998.
Nieun Seo Ji Hoon Shin Gi-Young Ko Hyun-Ki Yoon Dong-Il Gwon Jin-Hyoung Kim Kyu-Bo Sung 《Korean journal of radiology》2012,13(2):174-181
Objective
Upper gastrointestinal (GI) bleeding is a serious complication that sometimes occurs after percutaneous radiologic gastrostomy (PRG). We evaluated the incidence of bleeding complications after a PRG and its management including transcatheter arterial embolization (TAE).Materials and Methods
We retrospectively reviewed 574 patients who underwent PRG in our institution between 2000 and 2010. Eight patients (1.4%) had symptoms or signs of upper GI bleeding after PRG.Results
The initial presentation was hematemesis (n = 3), melena (n = 2), hematochezia (n = 2) and bloody drainage through the gastrostomy tube (n = 1). The time interval between PRG placement and detection of bleeding ranged from immediately after to 3 days later (mean: 28 hours). The mean decrease in hemoglobin concentration was 3.69 g/dL (range, 0.9 to 6.8 g/dL). In three patients, bleeding was controlled by transfusion (n = 2) or compression of the gastrostomy site (n = 1). The remaining five patients underwent an angiography because bleeding could not be controlled by transfusion only. In one patient, the bleeding focus was not evident on angiography or endoscopy, and wedge resection including the tube insertion site was performed for hemostasis. The other four patients underwent prophylactic (n = 1) or therapeutic (n = 3) TAEs. In three patients, successful hemostasis was achieved by TAE, whereas the remaining one patient underwent exploration due to persistent bleeding despite TAE.Conclusion
We observed an incidence of upper GI bleeding complicating the PRG of 1.4%. TAE following conservative management appears to be safe and effective for hemostasis. 相似文献999.
Dae Chul Jung Hak Jong Lee Jin Won Seo So Yeon Park Sang Jin Lee Joo Hyuk Lee In Hoo Kim 《Korean journal of radiology》2012,13(1):82-89
Objective
To assess the relationship between apparent diffusion coefficient (ADC) values on diffusion-weighted magnetic resonance (MR) imaging and pathologic measures of a tumor using a prostate cancer xenograft model.Materials and Methods
Eighteen athymic nude mice with 36 PC-3-induced tumors were sacrificed to obtain specimens immediately after MR imaging in order to compare the findings on MR images with those seen on pathological specimens. Using a high-field small-animal MR scanner, T1- and T2-weighted imaging and DW MR imaging was performed. Tumors were then processed for Hematoxylin and Eosin staining to evaluate tumor cellularity, intratumoral necrosis and immunostaining using antibodies directed against CD31 and vascular endothelial growth factor (VEGF) to determine the levels of microvessel density (MVD). Mean ADC values that were measured on the solid portion within each tumor were compared with tumor volume, cellularity, degree of necrosis, VEGF expression, and MVD in the corresponding section of the pathological specimen.Results
Mean ADC values of the solid portion within the PC-3-induced high-grade tumors were significantly correlated with the degree of intratumoral necrosis (r = 0.63, p < 0.0001) and MVD (r = -0.44, p = 0.008) on pathologic slides. The ADC values were not significantly correlated with tumor cellularity, VEGF expression, or tumor volume in high-grade prostate cancer tissues.Conclusion
In the xenografted prostate cancer model, the ADC values of the solid portion of the tumors are significantly correlated with tumor necrosis and MVD of the pathologic specimens. The ADC values may be utilized as surrogate markers for the noninvasive assessment of tumor necrosis and MVD in high-grade prostate cancer. 相似文献1000.
Yong Hyun Park Chang Min Yu Eun Sil Kim Jun Oh Jung Han Seok Seo Ju Hyoung Lee So Chong Hur So Yeon Kim Hyon Young Lee 《Nuclear Medicine and Molecular Imaging》2012,46(1):69-72
Due to the low yield of AFB smear and culture in extrapulmonary tuberculosis, therapeutic responses of patients with extrapulmonary tuberculosis are usually monitored clinically and/or radiographically. Such monitoring techniques, however, are not enough to provide effective diagnosis if a remnant lesion exists after treatment. Tuberculosis presents hypermetabolic activity on F-18 fluorodeoxyglucose positron emission tomography/computed tomography (F-18 FDG PET/CT) scanning. Reported herein is a case of extrapulmonary tuberculosis where the therapeutic response was assessed via serial F-18 FDG PET/CT scanning, which was useful for detecting the extent of extrapulmonary tuberculosis and for estimating the patient’s therapeutic response. 相似文献