全文获取类型
收费全文 | 204311篇 |
免费 | 19034篇 |
国内免费 | 10873篇 |
专业分类
耳鼻咽喉 | 1831篇 |
儿科学 | 3065篇 |
妇产科学 | 3967篇 |
基础医学 | 21648篇 |
口腔科学 | 4043篇 |
临床医学 | 25098篇 |
内科学 | 31242篇 |
皮肤病学 | 2572篇 |
神经病学 | 9872篇 |
特种医学 | 7080篇 |
外国民族医学 | 77篇 |
外科学 | 21594篇 |
综合类 | 32016篇 |
现状与发展 | 39篇 |
一般理论 | 39篇 |
预防医学 | 15036篇 |
眼科学 | 5388篇 |
药学 | 21985篇 |
196篇 | |
中国医学 | 11301篇 |
肿瘤学 | 16129篇 |
出版年
2024年 | 651篇 |
2023年 | 2983篇 |
2022年 | 7088篇 |
2021年 | 9551篇 |
2020年 | 7143篇 |
2019年 | 6205篇 |
2018年 | 6626篇 |
2017年 | 6255篇 |
2016年 | 5634篇 |
2015年 | 8554篇 |
2014年 | 10792篇 |
2013年 | 11088篇 |
2012年 | 15872篇 |
2011年 | 16895篇 |
2010年 | 11571篇 |
2009年 | 9507篇 |
2008年 | 11998篇 |
2007年 | 11844篇 |
2006年 | 11001篇 |
2005年 | 10061篇 |
2004年 | 7481篇 |
2003年 | 6820篇 |
2002年 | 5846篇 |
2001年 | 4932篇 |
2000年 | 4548篇 |
1999年 | 4124篇 |
1998年 | 2089篇 |
1997年 | 2000篇 |
1996年 | 1622篇 |
1995年 | 1484篇 |
1994年 | 1338篇 |
1993年 | 825篇 |
1992年 | 1427篇 |
1991年 | 1215篇 |
1990年 | 1075篇 |
1989年 | 932篇 |
1988年 | 810篇 |
1987年 | 718篇 |
1986年 | 575篇 |
1985年 | 460篇 |
1984年 | 323篇 |
1983年 | 270篇 |
1982年 | 165篇 |
1981年 | 171篇 |
1979年 | 223篇 |
1978年 | 157篇 |
1977年 | 122篇 |
1974年 | 142篇 |
1973年 | 114篇 |
1972年 | 142篇 |
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
991.
Andrea Lin Jasmine A. Mack Brittany Bruggeman Laura M. Jacobsen Amanda L. Posgai Clive H. Wasserfall Todd M. Brusko Mark A. Atkinson Stephen E. Gitelman Peter A. Gottlieb Matthew J. Gurka Clayton E. Mathews Desmond A. Schatz Michael J. Haller 《Diabetes》2021,70(5):1123
Previously, we demonstrated low-dose antithymocyte globulin (ATG) and granulocyte colony-stimulating factor (GCSF) immunotherapy preserved C-peptide for 2 years in a pilot study of patients with established type 1 diabetes (n = 25). Here, we evaluated the long-term outcomes of ATG/GCSF in study participants with 5 years of available follow-up data (n = 15). The primary end point was area under the curve (AUC) C-peptide during a 2-h mixed-meal tolerance test. After 5 years, there were no statistically significant differences in AUC C-peptide when comparing those who received ATG/GCSF versus placebo (P = 0.41). A modeling framework based on mean trajectories in C-peptide AUC over 5 years, accounting for differing trends between groups, was applied to recategorize responders (n = 9) and nonresponders (n = 7). ATG/GCSF reponders demonstrated nearly unchanged HbA1c over 5 years (mean [95% CI] adjusted change 0.29% [–0.69%, 1.27%]), but the study was not powered for comparisons against nonresponders 1.75% (–0.57%, 4.06%) or placebo recipients 1.44% (0.21%, 2.66%). These data underscore the importance of long-term follow-up in previous and ongoing phase 2 trials of low-dose ATG in recent-onset type 1 diabetes. 相似文献
992.
Glen Zi Qiang Liau Hong Yi Lin Yuhang Wang Kameswara Rishi Yeshayahu Nistala Chin Kai Cheong James Hoi Po Hui 《Indian Journal of Orthopaedics》2021,55(1):55
PurposeFractures of the femoral shaft in children are common. The rates of bone growth and remodeling in children vary according to their ages, which affect their respective management. MethodsThis paper evaluates the incidence and patterns of pediatric femoral shaft fracture and the current concepts of treatments available.ResultsThe type of fracture—closed or open; stable or unstable—needs to be taken into account. Child abuse should be suspected in fractures sustained by infants. For younger children, non-surgical management is preferred, which include Pavlik harness (< 6 months old) and early spica casting (6 months to 6 years old). Older children (> 6 years old) usually benefit from surgical treatments as outcomes of non-surgical alternatives are worse and are associated with prolonged recovery times. These operative measures for older children that are 6–12 years old include elastic stable intramedullary nailing and submuscular plating. Factors to be considered when devising an appropriate intervention include body mass, location of injury, and nature of fracture. For adolescent and skeletally mature teenagers (> 12 years old), rigid antegrade entry intramedullary fixation is indicated. In the event of open fractures or polytrauma, external fixation should be considered as a temporary treatment method for initial fracture stabilization.ConclusionAn age-based and evidence-based algorithm has been proposed to guide surgeons in the process of evaluating an appropriate treatment. 相似文献
993.
994.
You-Sheng Lin Yun Chen Ya-Hui Tsai Sheng-Hong Tseng Kuen-Song Lin 《Journal of pediatric surgery》2021,56(7):1227-1232
BackgroundPatients with neuroblastoma, a common childhood malignancy, often have poor prognosis. It is mandatory to develop an accurate and efficient diagnostic tool for neuroblastomas, so that the treatment can be started early. Graphene quantum dot (GQD), a nanomaterial, can be used to carry proteins, genetic materials, or drugs. GD2, a disialoganglioside, is a surface antigen expressed on neuroblastoma. This study investigated the in vivo targeting and imaging of neuroblastomas using GD2-targeting GQDs.MethodsGQDs were synthesized and conjugated with anti-GD2 antibody (anti-GD2/GQDs). In vitro cytotoxicity of GQDs and anti-GD2/GQDs was studied in human neuroblastoma cells by 3-[4,5-dimethylthiazole-2-yl]-2,5-diphenyltetrazolium bromide)-based colorimetric assay. The tumor tracking and imaging of anti-GD2/GQDs in mice were investigated by in vivo imaging system (IVIS).ResultsTreatment with GQDs or anti-GD2/GQDs induced no or mild cytotoxicity in fibroblasts and neuroblastoma cells. After co-incubation, GQDs and anti-GD2/GQDs were located in the cytoplasm and nucleus of neuroblastoma cells, with GQDs showing a blue fluorescence and anti-GD2/GQDs an orange/red emission. The IVIS images demonstrated accumulation of the fluorescence of anti-GD2/GQDs in the subcutaneous tumors in mice 24 h after intravenous injection of anti-GD2/GQDs.ConclusionsAnti-GD2/GQDs may potentially be used for the targeting and imaging of neuroblastomas in vivo. 相似文献
995.
目的:观察健脾祛湿方对脾虚湿盛型高脂血症大鼠血脂、胃肠功能、水液代谢的影响及作用机制。方法:将56只SD大鼠随机分为空白组(n=8)和造模组(n=48),采用“劳倦过度+饮食不节+高脂饲料喂养”复制脾虚湿盛型高脂血症大鼠模型。造模4周后,根据总胆固醇(TC)水平将造模组随机分成6组:即模型组,血脂康组,参苓白术颗粒组,健脾祛湿方低、中、高剂量组,每组8只。分组后开始给药,灌胃剂量为1 mL/100 g,空白组、模型组给予生理盐水,其余组给予相应的受试物,连续给药6周。测定血脂四项TC、三酰甘油(TG)、低密度脂蛋白胆固醇(LDL-Ch)和高密度脂蛋白胆固醇(HDL-Ch),胃肠激素,即胃动素(MTL)、促胃液素(GAS)和血管活性肠肽(VIP),水液调节激素醛固酮(ALD)、抗利尿激素(ADH)和心房利尿钠肽(ANP),以及白蛋白(ALB)和总蛋白(TP),采用苏木精-伊红(HE)染色法观察胃、结肠组织形态,免疫荧光法检测结肠水孔蛋白(AQP)3、胃AQP4的表达位置及水平,采用蛋白质印迹法(Western Blotting)检测结肠、胃组织中闭合蛋白(Occludin)的表达量。结果:与正常组比较,模型组大鼠血清TC、TG、LDL-Ch水平升高(P<0.001),HDL-Ch水平降低(P<0.05),血清MTL、GAS水平降低(P<0.001,P<0.01),VIP升高(P<0.001),ALD、ADH升高(P<0.05,P<0.001),ANP水平显著降低(P<0.001),TP、ALB水平降低(P<0.001,P<0.05)。结肠绒毛、胃黏膜出现大量脱落情况,结肠AQP3荧光强度降低,胃AQP4荧光表达增强,结肠、胃组织Occludin表达水平降低。与模型组比较,血脂康组、参苓白术颗粒组、健脾祛湿方低、中、高剂量组大鼠血清TC、TG、LDL-Ch水平呈下降趋势,HDL-C水平升高,MTL、GAS显著升高,VIP水平显著降低,ALD、ADH水平降低,ANP显著升高,结肠、胃组织形态结构有所改善。结肠AQP3荧光表达增强,胃AQP4荧光强度减弱,结肠、胃组织Occludin表达水平增强。结论:健脾祛湿方可降低脾虚湿盛型高脂血症大鼠血脂,有健脾祛湿之功,其作用机制可能是通过调节Occludin、AQP3、AQP4的表达,保护紧密连接结构的完整性达到促进胃肠消化吸收功能,改善水液代谢障碍的作用。 相似文献
996.
目的 基于甜味受体整合中药“效味”和“滋味”探索玉竹Polygonatum odoratum甘味药性物质基础,为中药药性物质研究提供新视角。方法 以多糖、皂苷、黄酮成分为玉竹甘味药性物质筛选对象,分析其对“阴虚”小鼠体质量、体温、食量、饮水量、大便含水量、皮肤含水量及Na+,K+-ATP酶、Ca2+,Mg2+-ATP酶活性和水通道蛋白1(aquaporin 1,AQP1)、AQP3 m RNA表达量的影响,基于“效味”探索玉竹甘味药性物质;以典型甘、苦、辛、酸、咸味中药建立中药“五味”标准,利用电子舌技术及主成分分析法(principal component analysis,PCA),分别比较玉竹多糖、皂苷、黄酮与中药“五味”的欧式距离及投射的区域,基于“滋味”探索玉竹甘味药性物质。将基于“效味”和“滋味”相同的甘味药性物质确定为玉竹甘味药性物质基础,并采用整体动物考察其对胰高血糖素样肽-1(glucagon-like peptide-1,GLP-1)分泌的影响,分子对接考察甘味药性物质与甜味受体... 相似文献
997.
黄芪多糖(Astragalus polysaccharides,APS)是黄芪的重要活性成分之一,随着黄芪在临床上的使用越来越广泛,学者对APS的提取工艺、化学结构及药理作用的研究也愈来愈深入。不同的提取工艺对APS的含量和纯度均会产生不同程度的影响,进而对其药理作用的发挥也会有所影响。APS具有调节免疫、抗肿瘤、降血糖、抗衰老和抗炎等药理作用。在全面查阅并梳理文献资料的基础上,对APS的提取工艺、化学结构及药理作用进行综述,并对APS的研究前景进行展望,以期对APS的进一步开发利用和研究提供有效的理论支持。 相似文献
998.
目的:观察参芪降糖颗粒治疗2 型糖尿病周围神经病变(DPN) 的疗效。方法:选取90 例DPN
患者,按随机数字表法分对照组和观察组各45 例。在西医常规治疗的基础上,对照组加用硫辛酸注射液治
疗,观察组在对照组的基础上加用参芪降糖颗粒治疗。2 组均连续治疗4 周。比较2 组临床疗效、糖化血红蛋
白(HbA1c)、空腹血糖(FBG)、餐后2 h 血糖(P2hBG), 以及胫神经、腓总神经的运动神经传导速
度(MNCV)、感觉神经传导速度(SNCV)。结果:观察组总有效率为93.33%,显著高于对照组的75.56%,
2 组比较,差异有统计学意义(P<0.05)。治疗前,2 组FBG、P2hBG、HbA1c 水平比较,差异无统计学意
义(P>0.05);治疗后,2 组FBG、P2hBG、HbA1c 水平均较治疗前明显降低(P<0.05),且观察组上述3 项
指标均低于对照组(P<0.05)。治疗前,2 组胫神经、腓总神经的MNCV、SNCV 比较,差异无统计学意
义(P>0.05);治疗后,2 组胫神经、腓总神经的MNCV、SNCV 均较治疗前明显升高(P>0.05),且观察组
上述各项指标改善较对照组更显著(P<0.05)。结论:参芪降糖颗粒辅助治疗2 型DPN,可进一步改善患者血
糖水平和周围神经病变,提高临床治疗效果。 相似文献
999.
Chun-xia Tian Ming-yue Li Xin-xin Shuai Feng Jiang Ya-lan Dong Yang Gui Zi-li Zhang Ren-jie Qin Zhen-yu Kang Lan Lin Alexey Sarapultsev Bin Wu Shan-shan Luo De-sheng Hu 《Phytotherapy research : PTR》2023,37(1):50-61
Myocardial infarction (MI) is one of the diseases with high fatality rate. Berberine (BBR) is a monomer compound with various biological functions. And some studies have confirmed that BBR plays an important role in alleviating cardiomyocyte injury after MI. However, the specific mechanism is unclear. In this study, we induced a model of MI by ligation of the left anterior descending coronary artery and we surprisingly found that BBR significantly improved ventricular remodeling, with a minor inflammatory and oxidative stress injury, and stronger angiogenesis. Moreover, BBR inhibited the secretion of Wnt5a/β-catenin pathway in macrophages after MI, thus promoting the differentiation of macrophages into M2 type. In summary, BBR effectively improved cardiac function of mice after MI, and the potential protective mechanism was associated with the regulation of inflammatory responses and the inhibition of macrophage Wnt5a/β-catenin pathway in the infarcted heart tissues. Importantly, these findings supported BBR as an effective cardioprotective drug after MI. 相似文献
1000.
目的:研究黄芩在河北省燕山及太行山山脉生态适宜性区划。方法:通过第四次全国中药资源普查等方式获取黄芩分布位点信息,利用地理信息系统技术和最大信息熵模型分析其分布区的主导生态因子、数值和权重,得出黄芩药材在河北省的生态适宜生长区。结果:研究表明,海拔、坡度、最暖季降水量、最湿月降水量、年均温、土壤类型、植被类型7项环境因子是影响黄芩分布的主要生态因子;黄芩在河北省的生态适宜生长区主要分布在承德、张家口、保定等地的燕山及太行山山脉区域。结论:可在太行山山脉的承德市、张家口市、保定市,燕山山脉的秦皇岛市引种栽培黄芩。 相似文献