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91.
Chia-Cheng Yu Chien-Feng Li I-Hsuan Chen Ming-Tsung Lai Zi-Jun Lin Praveen K Korla Chee-Yin Chai Grace Ko Chih-Mei Chen Tritium Hwang Shan-Chih Lee Jim J-C Sheu 《The Journal of pathology》2019,248(4):476-487
The objective of this study was to characterize the oncogenic actions of a recently identified cancer-associated gene YWHAZ (also named as 14-3-3 ζ/δ) in urothelial carcinomas of the urinary bladder (UCUB). A genome-wide study revealed YWHAZ to be involved in the amplicon at 8q22.3, and its genetic amplification was detected predominantly in muscle-invasive bladder cancer (MIBC). Immunohistochemical staining confirmed the association of YWHAZ overexpression with higher tumor stages, lymph node/vascular invasion, and mitotic activity. Univariate and multivariate analyses further indicated the prognostic potential of YWHAZ for more aggressive cancer types. Both gene set enrichment analysis and STRING network studies suggested involvement of YWHAZ in regulating caspase-mediated apoptosis. Ectopic expression of YWHAZ in bladder cells with low endogenous YWHAZ levels boosted cell resistance to doxorubicin and cisplatin, as well as to ionizing radiation. Conversely, YWHAZ-knockdown using specific shRNA in cells with high endogenous YWHAZ levels diminished survival activity, suppressing cell growth and increasing cell death. Our findings confirm the essential role played by YWHAZ in sustaining cell proliferation during chemo/radiotherapy. Treatments based on anti-YWHAZ strategies may thus be beneficial for UCUB patients overexpressing YWHAZ. © 2019 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of Pathological Society of Great Britain and Ireland. 相似文献
92.
Qian Chen Hai-Yan Weng Xiao-Peng Tang Yong Lin Ye Yuan Qian Li Zhuo Tang Hai-Bo Wu Shuai Yang Yong Li Xi-Long Zhao Wen-Juan Fu Qin Niu Hua Feng Xia Zhang Yan Wang Xiu-Wu Bian Xiao-Hong Yao 《The Journal of pathology》2019,247(2):266-278
Phosphatase and tensin homolog deleted on chromosome 10 (PTEN) deficiency in primary human glioblastoma (GBM) is associated with increased invasiveness and poor prognosis with unknown mechanisms. Therefore, how loss of PTEN promotes GBM progression remains to be elucidated. Herein, we identified that ADP-ribosylation factor like-4C (ARL4C) was highly expressed in PTEN-deficient human GBM cells and tissues. Mechanistically, loss of PTEN stabilized ARL4C protein due to AKT/mTOR pathway-mediated inhibition of ARL4C ubiquitination. Functionally, ARL4C enhanced the progression of GBM cells in vitro and in vivo. Moreover, microarray profiling and GST pull-down assay identified that ARL4C accelerated tumor progression via RAC1-mediated filopodium formation. Importantly, targeting PTEN potently inhibited GBM tumor progression in vitro and in vivo, whereas overexpression of ARL4C reversed the tumor progression impaired by PTEN overexpression. Clinically, analyses with patients' specimens validated a negative correlation between PTEN and ARL4C expression. Elevated ARL4C expression but PTEN deficiency in tumor was associated with poorer disease-free survival and overall survival of GBM patients. Taken together, ARL4C is critical for PTEN-deficient GBM progression and acts as a novel prognostic biomarker and a potential therapeutic candidate. Copyright © 2018 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd. 相似文献
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Guoping Du Xiaoshan Li Taha Hussein Musa Yu Ji Bo Wu Yan He Qian Ni Ling Su Wei Li You Ge 《Journal of medical virology》2019,91(3):401-410
Comprehensive data on hepatitis C virus (HCV) genotypes distribution is critical for treatment regimen selection, vaccine design, and drug development. This study aimed to understand the dynamic distribution of HCV genotypes in Mainland China. Three hundred sixty-two studies published from January 1993 to December 2017 involving 64 891 samples (5133 injecting drug users, 2748 volunteer blood donors, 1509 former paid plasma donors, 160 sexually encounters, and 1992 human immunodeficiency virus (HIV)/HCV coinfection patients) were eligible for the quantitative synthesis estimation. Pooled proportion of HCV genotypes (and 95% confidence intervals [CIs]) was estimated through the Freeman-Tukey double arcsine transformation by period, region, and risk group. A sharp decline of the subtype 1b was observed in all regions except in northwestern and central regions. The genotypes 3 and 6 showed an obvious increase in southern and southwestern regions and have already spread nationwide. After 2010, subtype 1b was the most dominant variant in all regions and risk groups, accounting for 54.0% (95% CI, 51.9-56.1) of all national infections. Subtype 2a was the second most prevalent strain in all regions except in the south and southwest, with 15.4% (95% CI, 13.1-17.8) national infections. The subtype 6a in southern region and 3b and 3a in southwestern region had a higher proportion of infections than that in other regions. In addition, the genotypes 3 and 6 are already prevalent in almost all risk groups. The distribution of HCV genotypes were sharply shifting in China in the past three decades. The HCV subtype 1b posed a sharp decline, whereas genotypes 3 and 6 played an increasing role in the regional and populational HCV pandemic. 相似文献
96.
Le Han Weijun He Huixin Yan Xianglan Li Chengmin Wang Qiumei Shi Tiezhong Zhou Guoying Dong 《Journal of medical virology》2019,91(4):711-716
To understand the evolution and molecular characteristics of Jiangxi H9N2 viruses, we isolated 17 viruses in 2011 and analyzed their characteristics. Phylogenetic analyses revealed that their hemagglutinin genes originate from JS/1/00-like sublineage, neuraminidase genes originate from BJ/94-like sublineage, PB1, PA, NP, and NS genes all come from SH/F/98-like sublineage, PB2 genes originate from ST/163/04-like sublineage, while M genes come from G1-like sublineage. Genotype analysis showed that our isolates were classified as genotype 57. Molecular analyses indicated that our strains contained specific sites characteristic of low-pathogenic viruses. The current study once again highlights the necessity for continued surveillance of novel H9N2 viruses. 相似文献
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Mingxia Li Xinxin Du Menghan Lu Weiyi Zhang Zhihui Sun Lian Li Mingxia Ye Wensheng Fan Shufang Jiang Aijun Liu Min Wang Yuanguang Meng Yali Li 《Journal of medical virology》2019,91(3):473-481
We assessed the prevalence characteristics of single and multiple high-risk human papillomavirus (HR-HPV) infections. A total of 1783 women who underwent colposcopy and cervical biopsy for abnormal ThinPrep Cytology Test and/or HR-HPV subtype genotyping results were enrolled in the study. Among the participants, 770 were diagnosed with cervicitis, 395 with cervical intraepithelial neoplasia grade 1 (CIN1), 542 with CIN2-3, and 76 with squamous cell carcinoma (SCC), with HR-HPV infection rates of 75.8%, 85.8%, 95.9%, and 88.4%, respectively. The prevalence of total and multiple HR-HPV infections exhibited a bimodal age distribution with a peak at ≤25 years, a decline with age and a second peak at ≥55 years, whereas single HR-HPV infections exhibited one peak from 35 to 44 years. The four most dominant HPV genotypes were HPV 16 (29.5%), 52 (15.0%), 58 (14.2%), and 18 (10.4%). In total, 67.0%, 70.4%, and 82.1% of patients with CIN1, CIN2-3, and SCC, respectively, had a single HR-HPV infection, which increased significantly with the aggravation of the cervical lesion grade (P = 0.045). Patients with a single HPV 16 infection had higher incidences of CIN2+ (62.2%) than those with multiple HPV 16 infections (52.4%) (P = 0.021). Patients coinfected with HPV 16 had higher CIN2+ incidence than those with single HPV 52, 31, 33, 35, 39, 45, 51, 56, or 59 infections (P < 0.001). This study provided baseline data on the prevalence characteristics of single and multiple HR-HPV infections in women attending a gynecological outpatient clinic in Beijing. 相似文献
100.
视网膜图像对变化检测主要研究两个不同时间点所采集到图像的变化情况。图像间的亮度差异及解剖结构与病灶的亮度相似性,使得基于逐点对比的差分方法或商方法很难准确检测变化区域。针对光照干扰问题,提出对光照具有鲁棒性的稀疏表示(SRC)变化检测方法。SRC方法先抽取参考图像局部区域块构建字典,再通过稀疏表示重构当前图像的局部背景块,最后利用背景相减获得变化区域。通过该方法,图像对的亮度差异可用稀疏表示系数自动调整,而基于块的方式可过滤掉局部光照,更有效地检测出变化区域。SRC方法与其他检测方法结合,可以增加检测结果的准确性。实验根据一对来自DRIVE数据集的小病灶仿真数据,SRC方法的AUC和mAP值分别为0.986和0.865;对一对采集自临床的大病灶数据,SRC与迭代鲁棒同态曲面拟合(IRHSF)校正结合方法的AUC和mAP值分别达到了0.989和0.969。实验结果表明,SRC方法比RPCA方法对局部光照鲁棒性更强,比基于逐点的比较差分方法更多地考虑局部邻域信息,能够更有效地检测出变化区域。 相似文献