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71.
Bone marrow edema and associated pain in early stage osteonecrosis of the femoral head: prospective study with serial MR images 总被引:31,自引:0,他引:31
PURPOSE: To determine the accuracy of magnetic resonance (MR) cholangiography for demonstration of the biliary tract and detection of biliary complications in patients who have undergone orthotopic liver transplantation. MATERIALS AND METHODS: Breath-hold half-Fourier rapid acquisition with relaxation enhancement MR cholangiography was performed in 25 patients who had undergone orthotopic liver transplantation. MR cholangiograms were prospectively and independently interpreted by two radiologists for depiction of the biliary tract and ductal anastomosis and for complications (eg, biliary dilatation, stricture, stones). MR cholangiographic findings were correlated with findings from direct cholangiography (n = 24) and surgery (n = 1). RESULTS: MR cholangiography completely demonstrated first-order intrahepatic bile ducts in 23 (92%) patients, the donor extrahepatic bile duct in 25 (100%), the recipient extrahepatic bile duct in 17 of 18 (94%), and the anastomosis in 24 (96%). The sensitivity, specificity, accuracy, positive predictive value, and negative predictive value of MR cholangiography for detection of biliary dilatation and stricture were each 100%. Complete interobserver agreement occurred in the detection of biliary dilatation and stricture. The sensitivity, specificity, accuracy, positive predictive value, and negative predictive value of MR cholangiography for detection of stones were 100% for one radiologist and 86%, 100%, 96%, 100%, and 95%, respectively, for the other. Both radiologists agreed on the diagnosis of bile duct stones in six of seven cases (kappa = 0.90). CONCLUSION: MR cholangiography enables accurate depiction of the biliary tract and detection of biliary complications in patients with an orthotopic liver transplant. 相似文献
72.
Yong -Hyun Kim Do -Youn Won Chang -Young Oh Nam -Tae Woo Young -Ho Park Jin -Hyun Jeong Won -Hun Ham 《Archives of pharmacal research》1999,22(3):300-301
Stereoselective synthesis of (+/-)-epibatidine analog 2, which contains the 8-azabicyclo[3.2.1]octane ring system, was achieved by using palladium-catalyzed Heck-type coupling reaction from 3. 相似文献
73.
Prognostic significance of c-kit mutation in localized gastrointestinal stromal tumors. 总被引:16,自引:0,他引:16
Tae Won Kim Hyoungnam Lee Yoon-Koo Kang Mi Sun Choe Min-Hee Ryu Heung Moon Chang Jung Sun Kim Jeong Hwan Yook Byung Sik Kim Jung Shin Lee 《Clinical cancer research》2004,10(9):3076-3081
PURPOSE: Constitutive mutational activation of c-kit has been found to be associated with the pathogenesis of gastrointestinal stromal tumors (GISTs). The prognostic significance of c-kit mutations, however, is still controversial. EXPERIMENTAL DESIGN: We examined 86 patients curatively resected for localized GIST. Genomic DNA was extracted from paraffin-embedded tumor tissues. Exons 9, 11, 13, and 17 of the c-kit gene were amplified by PCR and sequenced. RESULTS: Mutations in exon 11 were detected in 61 tumors, and mutations in exon 9 were observed in three tumors, whereas no mutations were detected in exons 13 or 17. The overall c-kit mutation frequency was 74%. Amino acid alterations in the 61 tumors with exon 11 mutations were deletion in 33 tumors, substitution in 20, both deletion and substitution in 4, insertion in 1, and duplication in 3. Histologically, tumors with c-kit mutations showed higher mitotic counts and higher cellularity. The 5-year relapse-free survival (RFS) in patients having GISTs with c-kit mutations was 21%, compared with 60% in those without c-kit mutations. Significantly higher RFS rates were observed in patients with tumors having mitotic counts < 5 mitoses/50 high power field, spindle-cell histology, tumor size < 5 cm, or gastric GISTs. Multivariate analyses indicated association of poorer RFS with a higher mitotic count > or = 5 of 50 high power fields; odds ratio (OR) = 3.0], presence of c-kit mutations (OR = 5.6), and a larger tumor size (> or = 5 cm; OR = 4.2). CONCLUSIONS: The presence of c-kit mutation, along with high mitotic count and larger tumor size, was an independent factor for poor prognosis in patients with localized GISTs. 相似文献
74.
Vascular endothelial growth factor gene polymorphisms and risk of primary lung cancer. 总被引:17,自引:0,他引:17
Su Jeong Lee Sin Yeob Lee Hyo-Sung Jeon Sun Ha Park Jin Sung Jang Ga Young Lee Ji Woong Son Chang Ho Kim Won Kee Lee Sin Kam Rang Woon Park Tae-In Park Young Mo Kang In-San Kim Tae Hoon Jung Jae Yong Park 《Cancer epidemiology, biomarkers & prevention》2005,14(3):571-575
Angiogenesis is an essential process in the development, growth, and metastasis of malignant tumors including lung cancer. DNA sequence variations in the vascular endothelial growth factor (VEGF) gene may lead to altered VEGF production and/or activity, thereby causing interindividual differences in the susceptibility to lung cancer via their actions on the pathways of tumor angiogenesis. To test this hypothesis, we investigated the potential association between three VEGF polymorphisms (-460T > C, +405C > G, and 936C > T)/haplotypes and the risk of lung cancer in a Korean population. VEGF genotypes were determined in 432 lung cancer patients and 432 healthy controls that were frequency matched for age and sex. VEGF haplotypes were predicted using Bayesian algorithm in the phase program. Compared with the combined +405 CC and CG genotype, the +405 GG genotype found associated with a significantly decreased risk of small cell carcinoma [SCC; adjusted odds ratio (OR), 0.36; 95% confidence interval (95% CI), 0.17-0.78]. The 936 CT genotype and the combined 936 CT and TT genotype were also associated with a significantly decreased risk of SCC compared with the 936 CC genotype (adjusted OR, 0.47; 95% CI, 0.26-0.85 and adjusted OR, 0.44; 95% CI, 0.24-0.80, respectively). Haplotype CGT was associated with a significantly decreased risk of SCC (adjusted OR, 0.39; 95% CI, 0.18-0.87), whereas haplotype TCC conferred a significantly increased risk of SCC (adjusted OR, 1.63; 95% CI, 1.14-2.33). None of the VEGF polymorphisms studied significantly influenced the susceptibility to lung cancer except SCC. However, haplotypes TCT and TGT were significantly associated with the risk of overall lung cancer, respectively (adjusted OR, 0.38; 95% CI, 0.25-0.60 and adjusted OR, 3.94; 95% CI, 2.00-7.76, respectively). These effects of haplotypes TCT and TGT on lung cancer risk were observed in three major histologic types of lung cancer. These results suggest that the VEGF gene may be contribute to an inherited predisposition to lung cancer. 相似文献
75.
Alveolar soft part sarcoma: MR and angiographic findings 总被引:5,自引:5,他引:0
Suh JS Cho J Lee SH Shin KH Yang WI Lee JH Cho JH Suh KJ Lee YJ Ryu KN 《Skeletal radiology》2000,29(12):680-689
Objective. To present the MR and angiographic findings of alveolar soft part sarcoma (ASPS).
Design and patients. MR examinations (12 tumors of 10 patients) of ASPS performed at multiple hospitals were retrospectively reviewed. The tumors
were found in the thigh (n=4), lower leg (n=4), femur (n=2, local metastasis), scalp (n=1) and arm (n=1). The MR signal characteristics including signal intensity, homogeneity and signal void of lesions and bony invasion including
direct invasion or local metastasis were evaluated. Angiographic findings (n=4) and post-embolotherapy follow-up MR imaging (n=2) findings were also assessed.
Results. Local bony metastasis was found in two cases. Seven tumors showed heterogeneous high signal intensity on T1- and T2-weighted
images with good enhancement. One tumor had a very high signal on T1-weighted images. Eight tumors (67%) showed numerous signal
voids in or near the tumors. All four angiographic studies showed numerous enlarged vessels, arteriovenous shunts and delayed
washout. Two cases mimicked arteriovenous malformations on angiographic studies but MR images demonstrated solid soft tissue
components as well as tortuous vessels.
Conclusions. High signal on T1-weighted image and numerous signal voids are highly suggestive of ASPS, although they are not universal
as has been suggested and arteriovenous malformation should be included in the differential diagnosis. Local bony metastases
in ASPS were seen in two cases and should be carefully investigated.
Received: 12 April 2000 Revision requested: 27 June 2000, 8 August 2000 Revision received: 2 August 2000, 21 August 2000 Accepted:
22 August 2000 相似文献
76.
77.
Novel oral transforming growth factor‐β signaling inhibitor EW‐7197 eradicates CML‐initiating cells 下载免费PDF全文
Kazuhito Naka Kaori Ishihara Yoshie Jomen Cheng Hua Jin Dong‐Hyun Kim Yoon‐Kang Gu Eun‐Sook Jeong Shaoguang Li Daniela S. Krause Dong‐Wook Kim Eunjin Bae Yoshihiro Takihara Atsushi Hirao Hiroko Oshima Masanobu Oshima Akira Ooshima Yhun Yhong Sheen Seong‐Jin Kim Dae‐Kee Kim 《Cancer science》2016,107(2):140-148
Recent strategies for treating CML patients have focused on investigating new combinations of tyrosine kinase inhibitors (TKIs) as well as identifying novel translational research agents that can eradicate CML leukemia‐initiating cells (CML‐LICs). However, little is known about the therapeutic benefits such CML‐LIC targeting therapies might bring to CML patients. In this study, we investigated the therapeutic potential of EW‐7197, an orally bioavailable transforming growth factor‐β signaling inhibitor which has recently been approved as an Investigational New Drug (NIH, USA), to suppress CML‐LICs in vivo. Compared to TKI treatment alone, administration of TKI plus EW‐7197 to CML‐affected mice significantly delayed disease relapse and prolonged survival. Notably, combined treatment with EW‐7197 plus TKI was effective in eliminating CML‐LICs even if they expressed the TKI‐resistant T315I mutant BCR‐ABL1 oncogene. Collectively, these results indicate that EW‐7197 may be a promising candidate for a new therapeutic that can greatly benefit CML patients by working in combination with TKIs to eradicate CML‐LICs. 相似文献
78.
Moon-Woo Seong Kyu Hyung Kim Il Yong Chung Eunyoung Kang Jong Won Lee Sue K. Park Min Hyuk Lee Jeong Eon Lee Dong-Young Noh Byung Ho Son Hai-Lin Park Sung Im Cho Sung Sup Park Sung-Won Kim 《Breast cancer research and treatment》2014,146(1):63-69
Triple-negative breast cancer (TNBC) accounts for 12–24 % of all breast cancers. Here, we studied 221 familial breast and/or ovarian cancer patients from 37 hospitals using a comprehensive approach to identify large genomic rearrangements (LGRs) as well as sequence variants, and investigated the association between BRCA1/2 mutational status and TNBC. We performed direct sequencing or mutation scanning followed by direct sequencing. Then, 143 BRCA1/2 mutation-negative patients were screened for LGRs. In this study, the prevalence of BRCA1/2 mutations was high (36.9 %). The prevalence of BRCA1 mutations was similar to that of BRCA2 mutations: 49.4 versus 50.6 %, respectively. TNBC was diagnosed in 35.2 % of BRCA1/2 mutation carriers and 57.1 % of BRCA1 mutation carriers. Conversely, two-thirds of TNBC patients carried BRCA1/2 mutation(s), and about half were BRCA1 mutation carriers. When stratified by the mutated gene, TNBC prevalence in BRCA1 mutation carriers was significantly lower when there was a family history of ovarian cancer. Our multinomial logistic regression model demonstrated that no single factor was sufficient, and at least two factors, such as a patient with family history of both breast cancer and ovarian cancer or a patient diagnosed at a relatively young age (<40 years) with a TNBC phenotype, are necessary to indicate BRCA1/2 genetic testing in this population. Our results suggest that TNBC is a strong predictor for the presence of a BRCA1 mutation in this population, but additional risk factors should also be evaluated to ascertain a 10 % or higher prior probability of BRCA1/2 mutation testing. 相似文献
79.
Inhibitory action of water soluble fraction of Terminalia chebula on systemic and local anaphylaxis 总被引:3,自引:0,他引:3
Shin TY Jeong HJ Kim DK Kim SH Lee JK Kim DK Chae BS Kim JH Kang HW Lee CM Lee KC Park ST Lee EJ Lim JP Kim HM Lee YM 《Journal of ethnopharmacology》2001,74(2):133-140
We investigated the effects of the water soluble fraction of Terminalia chebula (Combretaceae) (WFTC) on systemic and local anaphylaxis. WFTC administered 1h before compound 48/80 injection inhibited compound 48/80-induced anaphylactic shock 100% with doses of 0.01-1.0 g/kg. When WFTC was administered 5 or 10 min after compound 48/80 injection, the mortality also decreased in a dose-dependent manner. Passive cutaneous anaphylaxis was inhibited by 63.5+/-7.8% by oral administration of WFTC (1.0 g/kg). When WFTC was pretreated at concentrations ranging from 0.005 to 1.0 g/kg, the serum histamine levels were reduced in a dose-dependent manner. WFTC (0.01-1.0 mg/ml) also significantly inhibited histamine release from rat peritoneal mast cells (RPMC) by compound 48/80. However, WFTC (1.0 mg/ml) had a significant increasing effect on anti-dinitrophenyl IgE-induced tumor necrosis factor-alpha production from RPMC. These results indicate that WFTC may possess a strong antianaphylactic action. 相似文献
80.
Jun Young Park Ju Hyeon Kim Young Joo Sim Ho Joong Jeong Jae Hyun Lee Ghi Chan Kim 《Medicine》2022,101(35)
The purpose of this study was to confirm the association between the serum vitamin D levels and ischemic stroke lesion size, functional ability, and cognitive function in elderly ischemic stroke patients. This study included Korean ischemic stroke patients aged 65 to 85 years. The size of the lesion was measured in brain images taken within 24 hours of hospitalization. The level of 25-(OH) Vitamin D (ng/mL), a metabolite of vitamin D, in the serum collected within 48 hours of hospitalization, and the modified Barthel index (MBI), gait performance, the muscle power of hip and knee extensors on the hemiplegic side, and mini-mental status examination (MMSE) were recorded within 1 week of the onset of the disease. Each factor was compared through correlation analysis, and the significance was confirmed using the Spearman correlation coefficient method. The association between the serum vitamin D levels and the size of the ischemic stroke lesion, the MBI, gait performance, the muscle power of hip and knee extensors on the hemiplegic side, and the MMSE were analyzed. It was confirmed that there was a significant correlation between all the factors (P < .005). In patients with serum vitamin D levels of ≥ 30 ng/mL, both the functional ability and cognitive functions were better than in patients lower than 30 ng/mL. We confirmed the lower the level of serum vitamin D levels, the larger the size of the ischemic stroke lesion when it occurred in elderly Koreans. And we confirmed that serum vitamin D levels affected the functional ability and cognitive function. And we recommend that elderly Koreans should maintain their blood vitamin D level above 30 ng/mL. We believe that this will help preserve the functional ability and cognitive function when ischemic stroke occurred. 相似文献