全文获取类型
收费全文 | 85132篇 |
免费 | 5849篇 |
国内免费 | 2881篇 |
专业分类
耳鼻咽喉 | 545篇 |
儿科学 | 1928篇 |
妇产科学 | 1080篇 |
基础医学 | 12791篇 |
口腔科学 | 1308篇 |
临床医学 | 6225篇 |
内科学 | 13161篇 |
皮肤病学 | 1640篇 |
神经病学 | 7486篇 |
特种医学 | 1356篇 |
外国民族医学 | 14篇 |
外科学 | 6398篇 |
综合类 | 9876篇 |
预防医学 | 5700篇 |
眼科学 | 1227篇 |
药学 | 14455篇 |
11篇 | |
中国医学 | 3990篇 |
肿瘤学 | 4671篇 |
出版年
2023年 | 1009篇 |
2022年 | 1259篇 |
2021年 | 2129篇 |
2020年 | 2291篇 |
2019年 | 3298篇 |
2018年 | 3054篇 |
2017年 | 2615篇 |
2016年 | 2326篇 |
2015年 | 2555篇 |
2014年 | 4291篇 |
2013年 | 5294篇 |
2012年 | 4484篇 |
2011年 | 5392篇 |
2010年 | 4661篇 |
2009年 | 4087篇 |
2008年 | 3962篇 |
2007年 | 3744篇 |
2006年 | 3292篇 |
2005年 | 2774篇 |
2004年 | 2618篇 |
2003年 | 2459篇 |
2002年 | 1990篇 |
2001年 | 1825篇 |
2000年 | 1442篇 |
1999年 | 1420篇 |
1998年 | 1105篇 |
1997年 | 985篇 |
1996年 | 846篇 |
1995年 | 789篇 |
1994年 | 715篇 |
1993年 | 631篇 |
1992年 | 549篇 |
1991年 | 519篇 |
1990年 | 444篇 |
1989年 | 397篇 |
1988年 | 350篇 |
1986年 | 293篇 |
1985年 | 1222篇 |
1984年 | 1627篇 |
1983年 | 1259篇 |
1982年 | 1352篇 |
1981年 | 1284篇 |
1980年 | 986篇 |
1979年 | 897篇 |
1978年 | 655篇 |
1977年 | 506篇 |
1976年 | 583篇 |
1975年 | 482篇 |
1974年 | 337篇 |
1973年 | 335篇 |
排序方式: 共有10000条查询结果,搜索用时 18 毫秒
1.
《Vaccine》2022,40(19):2679-2695
Vaccinations are essential for preventing infectious diseases in children with chronic diseases as they have increased risk of infection from frequent use of biologics. Response to immunizations in this group is not well known.ObjectiveA systematic review was performed to evaluate three primary outcomes: efficacy; immunogenicity; and safety of vaccines in children with chronic conditions treated with biologics.MethodsThe protocol for our systematic review and meta-analysis was registered and published with PROSPERO. We searched electronic bibliographic databases for studies published from 2009 to 2019, focusing on vaccinations in children with chronic conditions treated with biologics.ResultsWe retrieved 532 records. Thirty-one full-text articles were selected, and 14 were included in the meta-analysis. No significant publication bias was found. Efficacy: limited data are available regarding the efficacy of vaccination, as most studies have focused on immunogenicity as surrogate outcome for efficacy. Immunogenicity: patients receiving anti-TNF-alpha therapy had a statistically significant risk of poor seroconversion (p = 0.028) and seroprotection by the serotype B influenza vaccine [inflammatory bowel disease (IBD) p = 0.013; juvenile idiopathic arthritis (JIA) p = 0.004]. We found adequate responses with H1N1 and H3N2 serotypes. Few studies existed for pneumococcal, hepatitis A virus, hepatitis B virus, varicella-zoster virus, Measles Mumps Rubella virus, and multiple vaccine administration. Safety: vaccine administration was not associated with serious side effects, but JIA patients on anti-TNF alpha therapy had a statistically significant risk of presenting with myalgia or arthralgia postinfluenza vaccine (p = 0.014).ConclusionsMore evidence concerning efficacy, immunogenicity, and safety of vaccinations is needed to guide physicians in the vaccine decision process for this pediatric population. 相似文献
2.
目的 观察治伤巴布剂对急性软组织损伤(acute soft tissue injury, ASTI)模型p38丝裂原活化蛋白激酶(mitogen-activated protein kinase,MAPK)、丝/苏氨酸蛋白激酶(AKT)信号通路的影响,探讨治伤巴布剂干预ASTI的可能作用机制。方法 将40只雄性SD大鼠按照随机数字表法分为正常对照组、模型对照组、治伤巴布剂组、p38MAPK信号通路抑制剂组、AKT信号通路抑制剂组,每组8只。除正常对照组外,其余四组均予以左侧后肢小腿ASTI造模。造模成功后,治伤巴布剂组于标记部位立即予治伤巴布剂(修剪成1.5x3cm大小)外敷,并用胶布固定;其余四组均予等剂量赋形剂(修剪成1.5×3 cm大小)外敷处理,胶布固定;持续外敷,共持续24 h。p38MAPK信号通路抑制剂组在造模前30 min予腹腔注射p38MAPK信号通路抑制剂SB203580(400 μg/kg/天)1次;AKT信号通路抑制剂组在造模前30 min予腹腔注射AKT信号通路抑制剂perifosine(20 mg/kg/天)1次。分别于0(造模前)、2h、4h、8h、12h、24h测量受伤小腿肌肉处的周长,并计算肌肉肿胀率(muscle swelling rate,MSR)。24 h药物干预结束后,采用颈椎脱臼法处死大鼠。后将左侧后肢小腿损伤中心部位进行取材,分成三份。一部分用于观察组织病理学形态变化;一部分用于逆转录聚合酶链反应(RT-PCR)检测核因子-κB(nuclear factor kappa-B,NF-κB)p65 mRNA、肿瘤坏死因子-α(TNF-α)mRNA、白细胞介素-1β(IL-1β)mRNA表达水平;剩下部分用酶联免疫吸附试验(ELISA)法检测骨骼肌组织TNF-α、IL-1β含量水平及蛋白质免疫印迹(Western-blot)法测定p38MAPK、AKT、NF-κB p65、核因子抑制蛋白α(inhibitor kappa B alpha, IκBα)表达水平。结果 与正常对照组相比,模型对照组MSR显著增加(P<0.01);病理形态学上,骨骼肌组织可见大面积肌细胞排列紊乱,肌细胞变性坏死,间质内可见红细胞聚集及大量炎症细胞浸润;骨骼肌组织TNF-α、IL-1β含量水平显著升高(P<0.01);磷酸化p38MAPK(p-p38)/总p38MAPK(t-p38),磷酸化-AKT(p-AKT)/总-AKT(t-AKT)明显升高(P<0.01),NF-κB p65及NF-κB p65mRNA表达水平明显升高(P<0.01)。与模型对照组相比,治伤巴布剂组MSR在治疗第8 h、12 h、24 h显著下降(P<0.01),且在治疗第24 h,其MSR较p38MAPK、AKT信号通路抑制剂组下降更明显(P<0.05);病理学评分显著下降(P<0.01),且较p38MAPK、AKT信号通路抑制剂组下降更显著(P<0.05);骨骼肌组织TNF-α、IL-1β含量水平明显下降(P<0.01),且较p38MAPK、AKT信号通路抑制剂组更显著(P<0.05);p-p38/t-p38及p-AKT/t-AKT明显下降(P<0.01),NF-κB p65及NF-κB p65 mRNA表达水平显著下降(P<0.01),且较p38MAPK、AKT信号通路抑制剂组在降低NF-κB p65及NF-κB p65 mRNA相对表达值方面更显著(P<0.01)。结论 治伤巴布剂可能同时对p38MAPK、AKT信号通路产生了一定的抑制作用,引起NF-κB活性下调,NF-κB p65蛋白的表达下调,进而引起骨骼肌组织TNF-α、IL-1β炎性细胞因子含量水平下调,减轻ASTI炎症反应,从而改善ASTI。 相似文献
3.
目的:探索嘌呤能受体X1(purinergic receptor,P2RX1)与肺腺癌(LUAD)患者预后及免疫细胞浸润的相关性。方法:利用生物信息学技术分析非小细胞肺癌中P2RX1的表达及其甲基化与患者预后的关系,对P2RX1共表达基因进行富集分析并筛选核心基因。利用TIMER 2.0数据库、R软件等分析P2RX1与免疫细胞、免疫检查点、免疫基质评分等的相关性。结果:P2RX1在LUAD中表达下调,低表达P2RX1的患者预后较差(P<0.05),且P2RX1与肿瘤纯度、分期等临床病理因素有关(P<0.05)。P2RX1的表达与肺鳞癌患者预后无明显相关。Cg06475633等P2RX1 CpG位点甲基化与患者预后相关。P2RX1共表达基因主要富集于免疫细胞活化、分化等通路和生物学进程,核心基因主要包括BTK、IKZF1等。P2RX1的表达与B细胞浸润、免疫/基质评分、PD-1、CTLA-4等多个免疫检查点显著相关(P<0.05)。结论:P2RX1有望成为LUAD诊断和免疫治疗的新靶点。 相似文献
4.
5.
目的 测定儿童1型糖尿病(T1DM)患者骨密度(BMD),分析探讨骨密度变化的影响因素。方法 选取于2018年1月—2021年6月于我院收治的儿童1型糖尿病患者76例,收集性别、年龄、发病年龄、身高、体重、BMI、病程等基本资料,检测空腹血糖、空腹C肽、糖化血红蛋白(HbA1c)、血碳酸氢根(HCO3-)、血清碱性磷酸酶(ALP),应用双能X线吸收测定法测定骨密度,获取Z值。结果 76例儿童1型糖尿病患者骨密度Z值为-0.93±2.14。HbA1c、病程与骨密度Z值呈负相关,差异具有统计学意义(分别B=-0.334,P<0.001;B=-0.191,P=0.017)。结论 儿童1型糖尿病患者骨密度低于健康儿童,血糖控制不良、病程长是1型糖尿病儿童骨密度减低的危险因素。 相似文献
6.
Defects of the cystic fibrosis (CF) transmembrane conductance regulator (CFTR) protein affect the homeostasis of chloride, bicarbonate, sodium, and water in the airway surface liquid, influencing the mucus composition and viscosity, which induces a severe condition of infection and inflammation along the whole life of CF patients. The introduction of CFTR modulators, novel drugs directly intervening to rescue the function of CFTR protein, opens a new era of experimental research. The review summarizes the most recent advancements to understand the characteristics of the infective and inflammatory pathology of CF lungs. 相似文献
7.
XI Hui CHENG Guan Liang HU Fei Fei LI Song Nan DENG Xuan ZHOU Yong 《Biomedical and environmental sciences : BES》2022,35(3):206-214
Objective To explore associations between lipoprotein-associated phospholipase A2(Lp-PLA2) and the risk of cardiovascular events in a Chinese population, with a long-term follow-up.Methods A random sample of 2,031 participants(73.6% males, mean age = 60.4 years) was derived from the Asymptomatic Polyvascular Abnormalities Community study(APAC) from 2010 to 2011. Serum Lp-PLA2 levels were determined by enzyme-linked immunosorbent assay(ELISA). The composite endpoint was a combination of first-eve... 相似文献
8.
目的 研究社区获得性肺炎(community acquired pneumonia,CAP)患儿血清维生素A(vitamin A,VA)水平及与免疫功能的相关性,为肺炎病情评估提供一定参考。方法 以入住新乡医学院第一附属医院PICU的63例重度社区获得性肺炎(severe community acquired pneumonia, SCAP)患儿(SCAP组)、普通儿科病区的30例轻度社区获得性肺炎(mild community acquired pneumonia, MCAP)患儿(MCAP组),以及同期体检的30名健康儿童(对照组)为研究对象,检测其血清中VA和免疫球蛋白(immunoglobulin,Ig)G、IgA、IgM水平,及SCAP组体内T淋巴细胞亚群(总T淋巴细胞、CD4、CD8、CD4/CD8),并对SCAP组体内VA水平及以上指标的相关性进行分析。结果 3组性别和年龄差异无统计学意义;血清中VA的平均含量分别为0.36、0.25和0.19 mg/L,CAP组VA的含量较对照组明显降低,且SCAP组明显低于MCAP组( <0.05)。根据WHO推荐的VA诊断标准,3组VA临床缺乏/亚临床缺乏率分别为10.00%、36.67%和61.90%,差异有统计学意义( <0.05)。CAP组血清中Ig水平较对照组明显降低,且SCAP组明显低于MCAP组( <0.05)。SCAP组血中总T淋巴细胞、CD4、CD8和CD4/CD8的平均水平分别为53.28%、30.26%、20.24%和1.59;分析VA水平与免疫相关指标关系发现VA水平与Ig(IgG、IgA、IgM)水平、总T淋巴细胞、CD4呈正相关,与CD8水平不相关。结论 肺炎患儿血清VA水平与病情严重程度及机体免疫功能相关。 相似文献
9.
《European journal of surgical oncology》2022,48(6):1264-1271
BackgroundIn order to avoid excessive treatment of thyroid nodules in the clinic, it is necessary to find a simple and practical analysis method to comprehensively and accurately reflect benign or malignant thyroid nodules. This study aimed to construct and validate a comprehensive and reliable network-based predictive model using a variety of imaging and laboratory criteria for thyroid nodules to stratify the risk of malignancy prior to surgery.MethodsWe retrospectively analyzed data from patients who underwent surgical treatment for thyroid nodules at the Thyroid and Breast Diagnosis and Treatment Center of Weifang Hospital of Traditional Chinese Medicine between January 2018 and December 2020. Binary logical regression analysis was performed to predict whether nodules were malignant or benign. The developmental dataset included 457 patients (January 2018–December 2020). The validation set included separate data points (n = 225, January 2018–December 2020).ResultsIn this study, criteria that showed significant predictive value for malignant nodules included TI-RADS: 4b (p = 0.065); Bethesda IV, Bethesda V, Bethesda VI (P < 0.0001); BRAFV600E mutation (P < 0.0001); Calcitonin>5 pg/ml (p = 0.0037); and FNA-Tg>30 ng/ml (p = 0.0003). A 10-grade risk scoring system was developed. The risk of malignancy risk ranged from 2.06% to 100% and was positively associated with increasing risk grade. The areas under the receiver-operating characteristic curve of the development and validation sets were 0.972 and 0.946, respectively.ConclusionA simple, comprehensive and reliable web-based predictive model was designed using a variety of imaging and laboratory criteria to stratify thyroid nodules by probability of malignancy. 相似文献
10.