全文获取类型
收费全文 | 146106篇 |
免费 | 15631篇 |
国内免费 | 10072篇 |
专业分类
耳鼻咽喉 | 1250篇 |
儿科学 | 1968篇 |
妇产科学 | 975篇 |
基础医学 | 11911篇 |
口腔科学 | 2568篇 |
临床医学 | 17838篇 |
内科学 | 15523篇 |
皮肤病学 | 1258篇 |
神经病学 | 5113篇 |
特种医学 | 5957篇 |
外国民族医学 | 39篇 |
外科学 | 14055篇 |
综合类 | 36424篇 |
现状与发展 | 32篇 |
一般理论 | 16篇 |
预防医学 | 14430篇 |
眼科学 | 2273篇 |
药学 | 17342篇 |
185篇 | |
中国医学 | 13714篇 |
肿瘤学 | 8938篇 |
出版年
2024年 | 232篇 |
2023年 | 1919篇 |
2022年 | 4188篇 |
2021年 | 5921篇 |
2020年 | 5484篇 |
2019年 | 3557篇 |
2018年 | 3887篇 |
2017年 | 4491篇 |
2016年 | 3788篇 |
2015年 | 6538篇 |
2014年 | 8241篇 |
2013年 | 9255篇 |
2012年 | 13419篇 |
2011年 | 14335篇 |
2010年 | 11675篇 |
2009年 | 9983篇 |
2008年 | 10604篇 |
2007年 | 10150篇 |
2006年 | 9392篇 |
2005年 | 7912篇 |
2004年 | 5422篇 |
2003年 | 4791篇 |
2002年 | 3917篇 |
2001年 | 3248篇 |
2000年 | 2699篇 |
1999年 | 1552篇 |
1998年 | 835篇 |
1997年 | 792篇 |
1996年 | 624篇 |
1995年 | 575篇 |
1994年 | 439篇 |
1993年 | 322篇 |
1992年 | 262篇 |
1991年 | 228篇 |
1990年 | 212篇 |
1989年 | 192篇 |
1988年 | 143篇 |
1987年 | 133篇 |
1986年 | 110篇 |
1985年 | 98篇 |
1984年 | 52篇 |
1983年 | 51篇 |
1982年 | 37篇 |
1981年 | 24篇 |
1980年 | 15篇 |
1979年 | 17篇 |
1978年 | 7篇 |
1973年 | 5篇 |
1972年 | 6篇 |
1971年 | 4篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
利用生物信息学技术初步探索芫根调控肠道免疫功能的分子生物学机制。方法 选择雄性SPF级BALB/c小鼠18只,随机分为3组,每组6只。SC1组小鼠每只每次灌胃芫根提取液150 μL,SC2组小鼠每只每次灌胃绞碎芫根原浆悬液150 μL,NC组小鼠每只每次灌胃生理盐水150 μL,连续7 d每日灌胃一次。分别取每组小鼠小肠组织样品提取RNA,总RNA的质检合格后,进行转录组测序。按GO功能和KEGG信号通路对差异表达基因聚类分析揭示差异表达高度富集的免疫相关通路。从免疫角度分析芫根灌胃小鼠小肠组织的基因表达变化情况。结果 转录组测序共检测到27733条 mRNA的表达,SC1组与NC组比较,显著差异表达基因1635个,其中上调差异表达基因1236个,下调差异表达基因399个;SC2组与NC组比较,显著差异表达基因2872个,其中上调差异表达基因2233个,下调差异表达基因639个(P<0.05)。按GO功能和KEGG信号通路聚类分析显示差异表达基因在白介素分泌、干扰素反应、T细胞受体信号通路及维生素和脂肪消化吸收等途径的富集度在两个芫根组中均居于前20位(P<0.01),肠黏膜趋化因子CCL20和巨噬细胞极化标志物CD274等免疫蛋白编码基因差异表达显著且同属于上述多个免疫通路。结论 芫根灌胃小鼠小肠的差异表达基因在白介素分泌、干扰素反应、T细胞受体信号通路、营养物质消化吸收等途径高度富集,提示芫根对肠道免疫系统及肠黏膜功能的调节,其中CD274的表达上调和CCL20的表达下调提示诱导M1型巨噬细胞极化和T细胞活化可能是芫根调控免疫和维护肠道正常结构功能的重要途径。 相似文献
2.
目的 总结儿童胃石症的临床特点及治疗经验.方法 回顾性分析郑州大学第一附属医院2009年6月至2020年6月收治的9例胃石症患儿临床资料.结果 9例胃石症患儿均为女性,年龄为4~13岁,其中8例有异食癖,1例发病前曾大量进食柿子.7例经内镜检查确诊,1例经CT确诊,1例经消化道造影确诊.4例经内镜取石治疗,5例经外科手术治疗,最终8例确诊为毛发性胃石症,1例为植物性胃石症.随访1~2 a,9例患儿均恢复良好,胃石症未复发,贫血及营养不良状况均有不同程度改善.结论 儿童胃石症常见于女童,多伴有异食癖,一经诊断应及时治疗,首选内镜取石,内镜取出失败可考虑外科手术治疗,治疗效果及患儿预后好. 相似文献
3.
Li Na Gou Zhong-Ping Du Shuang-Qing Zhu Xiao-Hong Lin Hui Liang Xiu-Fang Wang Yong-Sheng Feng Ping 《Clinical rheumatology》2022,41(3):689-693
Clinical Rheumatology - 相似文献
5.
Lei Qi Mingxing Wang Yuehui Jia Yuanyuan Wang Liangfang Xue Linlin Du Shuxiu Hao Shengqi Su Ruixiang Wang Huixin Sun Chen Feng Guijin Li Qingyu Zeng Cunqi Lv Jiacheng Li Qi Li Yunyan Zhang Tong Wang 《International journal of cancer. Journal international du cancer》2023,153(6):1172-1181
Information regarding the impact of the coronavirus disease 2019 (COVID-19) pandemic on cervical cancer in mainland China is lacking. We explored its impact on the hospital attendance of patients with primary cervical cancer. We included 1918 patients with primary cervical cancer who initially attended Harbin Medical University Cancer Hospital between January 23, 2019, and January 23, 2021. Attendance decreased by 31%, from 1135 in 2019 to 783 in 2020, mainly from January to June (𝜒2 = 73.362, P < .001). The percentage of patients detected by screening decreased from 12.1% in January-June 2019 to 5.8% in January-June 2020 (𝜒2 = 7.187, P = .007). Patients with stage I accounted for 28.4% in 2020 significantly lower than 36.6% in 2019 (𝜒2 = 14.085, P < .001), and patients with stage III accounted for 27.1% in 2020 significantly higher than 20.5% in 2019 (𝜒2 = 11.145, P < .001). Waiting time for treatment was extended from 8 days (median) in January-June and July-December 2019 to 16 days in January-June (𝜒2 = 74.674, P < .001) and 12 days in July-December 2020 (𝜒2 = 37.916, P < .001). Of the 179 patients who delayed treatment, 164 (91.6%) were for the reasons of the healthcare providers. Compared to 2019, the number of patients in Harbin or non-Harbin in Heilongjiang Province and outside the province decreased, and cross-regional medical treatment has been hindered. The COVID-19 pandemic has negatively impacted cervical cancer patient attendance at the initial phase. These results are solid evidence that a strategy and mechanism for the effective attendance of cervical cancer patients in response to public health emergencies is urgently needed. 相似文献
7.
Mixed lineage leukemia 1(MLL1)是组蛋白甲基转移酶SET家族的成员之一。MLL1与WDR5、RbBP5、Ash2L和DPY-30组成MLL1甲基转移酶复合物调控组蛋白H3的第4位赖氨酸的甲基化水平,对造血系统的发育和血细胞的更新至关重要。部分白血病患者体内存在因MLL1基因易位而产生的致癌蛋白——MLL1融合蛋白,MLL1融合蛋白在发挥其致癌作用时需要功能完整的MLL1酶复合物,故靶向MLL1-WDR5的蛋白-蛋白相互作用成为治疗MLL1融合型白血病的潜在策略。本文对MLL1-WDR5蛋白-蛋白相互作用的生物学机制、结构信息以及抑制剂进行了系统的总结,并结合已报道数据对该领域进行了展望,以期为后续研究提供参考。 相似文献
8.
9.
Qiang Liu Zhongbiao Xu Kaixuan Zhao W. Scott Hoge Xinyuan Zhang Yingjie Mei Qiqi Lu Thoralf Niendorf Yanqiu Feng 《NMR in biomedicine》2022,35(5):e4652
The purpose of this study was to investigate the feasibility of two-dimensional (2D) navigated, interleaved multishot echo-planar imaging (EPI) to enhance kidney diffusion-weighted imaging (DWI) in rats at 7.0 T. Fully sampled interleaved four-shot EPI with 2D navigators was tailored for kidney DWI (Sprague–Dawley rats, n = 7) on a 7.0-T small bore preclinical scanner. The image quality of four-shot EPI was compared with T2-weighted rapid acquisition with relaxation enhancement (RARE) (reference) and single-shot EPI (ss-EPI) without and with parallel imaging (PI). The contrast-to-noise ratio (CNR) was examined to assess the image quality for the EPI approaches. The Dice similarity coefficient and the Hausdorff distance were used for evaluation of image distortion. Mean diffusivity (MD) and fractional anisotropy (FA) were calculated for renal cortex and medulla for all DWI approaches. The corticomedullary difference of MD and FA were assessed by Wilcoxon signed-rank test. Four-shot EPI showed the highest CNR among the three EPI variants and lowest geometric distortion versus T2-weighted RARE (mean Dice: 0.77 for ss-EPI without PI, 0.88 for ss-EPI with twofold undersampling, and 0.92 for four-shot EPI). The FA map derived from four-shot EPI clearly identified a highly anisotropic region corresponding to the inner stripe of the outer medulla. Four-shot EPI successfully discerned differences in both MD and FA between renal cortex and medulla. In conclusion, 2D navigated, interleaved multishot EPI facilitates high-quality rat kidney DWI with clearly depicted intralayer and interlayer structure and substantially reduced image distortion. This approach enables the anatomic integrity of DWI-MRI in small rodents and has the potential to benefit the characterization of renal microstructure in preclinical studies. 相似文献
10.