全文获取类型
收费全文 | 11190篇 |
免费 | 1040篇 |
国内免费 | 403篇 |
专业分类
耳鼻咽喉 | 94篇 |
儿科学 | 92篇 |
妇产科学 | 95篇 |
基础医学 | 2380篇 |
口腔科学 | 212篇 |
临床医学 | 794篇 |
内科学 | 1514篇 |
皮肤病学 | 167篇 |
神经病学 | 909篇 |
特种医学 | 616篇 |
外国民族医学 | 3篇 |
外科学 | 463篇 |
综合类 | 1225篇 |
现状与发展 | 7篇 |
预防医学 | 536篇 |
眼科学 | 185篇 |
药学 | 1566篇 |
2篇 | |
中国医学 | 457篇 |
肿瘤学 | 1316篇 |
出版年
2024年 | 29篇 |
2023年 | 185篇 |
2022年 | 288篇 |
2021年 | 449篇 |
2020年 | 358篇 |
2019年 | 328篇 |
2018年 | 331篇 |
2017年 | 370篇 |
2016年 | 405篇 |
2015年 | 439篇 |
2014年 | 663篇 |
2013年 | 858篇 |
2012年 | 649篇 |
2011年 | 684篇 |
2010年 | 616篇 |
2009年 | 651篇 |
2008年 | 655篇 |
2007年 | 589篇 |
2006年 | 549篇 |
2005年 | 476篇 |
2004年 | 442篇 |
2003年 | 366篇 |
2002年 | 332篇 |
2001年 | 260篇 |
2000年 | 201篇 |
1999年 | 166篇 |
1998年 | 182篇 |
1997年 | 170篇 |
1996年 | 142篇 |
1995年 | 130篇 |
1994年 | 92篇 |
1993年 | 81篇 |
1992年 | 68篇 |
1991年 | 55篇 |
1990年 | 37篇 |
1989年 | 51篇 |
1988年 | 25篇 |
1987年 | 19篇 |
1986年 | 30篇 |
1985年 | 35篇 |
1984年 | 43篇 |
1983年 | 23篇 |
1982年 | 18篇 |
1981年 | 16篇 |
1980年 | 15篇 |
1979年 | 15篇 |
1978年 | 11篇 |
1976年 | 8篇 |
1973年 | 8篇 |
1972年 | 5篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
目的 基于“伏风暗瘀宿痰”小儿哮喘病机新说,采用网络药理学及实验验证的方法,探索搜风愈喘方拆方“祛宿痰方”治疗儿童哮喘的作用机制,验证中医“宿痰”病机与西医细胞外基质改变病理之间的交通性。方法 通过TCMSP数据库建立“祛宿痰方”的有效成分和靶点数据集,利用OMIM、GeneCards、DrugBank、TTD疾病数据库建立哮喘疾病靶点数据集,利用Cytoscape软件取交集并构建“祛宿痰方”与哮喘的蛋白质互作网络,筛选关键靶点蛋白。利用Metascape数据库进行基因本体(Gene ontology,GO)分析以及京都基因和基因组百科全书(Kyoto encyclopedia of genes and genomes,KEGG)富集分析。复制卵蛋白(OVA)诱导的哮喘大鼠模型,对核心通路及关键靶点进行实验验证。结果 共得到“祛宿痰方”治疗哮喘的靶点98个,包括IL-13、TP53、TGF-β1、VEGF-A、MMP9等,KEGG得到与哮喘相关的通路287条(P<0.05),包括NF-κB信号通路、PI3K-AKT信号通路、IL-17信号通路等。GO结果显示与哮喘相关生物进程包括炎症反应、细胞外基质调控、氧化应激、血管生成等。动物实验证实“祛宿痰方”可下调大鼠肺组织中p-NF-κB-P65磷酸化水平,抑制NF-κB信号通路的激活,降低IL-13、TGF-β1 mRNA表达量(P<0.05),减少哮喘大鼠肺组织中炎症细胞浸润、黏液产生,从而延缓哮喘的进程。结论 “祛宿痰方”可抑制NF-κB信号通路的激活,降低肺组织中IL-13、TGF-β1 mRNA表达量,可能通过抑制炎症反应、调控细胞外基质等途径作用于哮喘,中医“宿痰”病机与西医细胞外基质改变病理之间存在一定的的交通性。 相似文献
2.
3.
《Clinical neurophysiology》2019,130(12):2231-2237
ObjectiveThe clinical and neurophysiological characteristics of myoclonus in Angelman syndrome (AS) have been evaluated in single case or small cohorts, with contrasting results. We evaluated the features of myoclonus in a wide cohort of AS patients.MethodsWe performed polygraphic EEG-EMG recording in 24 patients with genetically confirmed AS and myoclonus. Neurophysiological investigations included jerk-locked back-averaging (JLBA), cortico-muscular coherence (CMC) and generalised partial directed coherence (GPDC). CMC and GPDC analyses were compared to those obtained from 10 healthy controls (HC).ResultsTwenty-four patients (aged 3–35 years, median 20) were evaluated. Sequences of quasi-continuous rhythmic jerks mostly occurred at alpha frequency or just below (mean 8.4 ± 1.4 Hz), without EEG correlate. JLBA did not show any clear transient preceding the jerks. CMC showed bilateral over-threshold CMC in alpha band that was prominent on the contralateral hemisphere in the patient group as compared to HC group. GPDC showed a significantly higher alpha outflow from both hemispheres toward activated muscles in the patient group, and a significantly higher beta outflow from contralateral hemisphere in the HC group.ConclusionsThese neurophysiological findings suggest a subcortical generator of myoclonus in AS.SignificanceMyoclonus in AS has not a cortical origin as previously hypothesised. 相似文献
4.
《Neuropsychopharmacology》2019,85(11):956-965
BackgroundBinge eating and other forms of disordered eating behavior (DEB) are associated with failed inhibitory control. This study investigated the neural correlates of failed inhibitory control as a potential biomarker for DEB.MethodsThe study used prospective longitudinal data from the European IMAGEN study adolescent cohort. Participants completed baseline assessments (questionnaires and a brain scan [functional magnetic resonance imaging]) at 14 years of age and a follow-up assessment (questionnaires) at 16 years of age. Self-reported binge eating and/or purging were used to indicate presence of DEB. Neural correlates of failed inhibition were assessed using the stop signal task. Participants were categorized as healthy control subjects (reported no DEB at both time points), maintainers (reported DEB at both time points), recoverers (reported DEB at baseline only), and developers (reported DEB at follow-up only). Forty-three individuals per group with complete scanning data were matched on gender, age, puberty, and intelligence (N = 172).ResultsAt baseline, despite similar task performance, incorrectly responding to stop signals (failed inhibitory control) was associated with greater recruitment of the medial prefrontal cortex and anterior cingulate cortex in the developers compared with healthy control subjects and recoverers.ConclusionsGreater recruitment of the medial prefrontal and anterior cingulate regions during failed inhibition accords with abnormal evaluation of errors contributing to DEB development. As this precedes symptom onset and is evident despite normal task performance, neural responses during failed inhibition may be a useful biomarker of vulnerability for DEB. This study highlights the potential value of prospective neuroimaging studies for identifying markers of illness before the emergence of behavior changes. 相似文献
5.
A. Cattapan K. Browne D.M. Halperin A. Di Castri P. Fullsack J. Graham J.M. Langley B.A. Taylor S.A. McNeil S.A. Halperin 《Vaccine》2019,37(2):289-295
Introduction/Hypothesis
Recruitment of participants into phase 1 vaccine clinical trials can be challenging since these vaccines have not been used in humans and there is no perceived benefit to the participant. Occasionally, as was the case with a phase 1 clinical trial of an Ebola vaccine in Halifax, Canada, during the 2014–2016 West African Ebola virus outbreak, recruitment is less difficult. In this study, we explored the motivations of participants in two phase 1 vaccine trials that were concurrently enrolling at the same centre and compared the motivations of participants in a high-profile phase 1 Ebola vaccine trial to those in a less high-profile phase 1 adjuvanted seasonal influenza vaccine study.Methods
An online survey which included participants’ prior experience with clinical trials, motivations to participate (including financial incentives), and demographic information was developed to examine the motivations of healthy participants in two phase 1 clinical vaccine trials conducted at the Canadian Center for Vaccinology in Halifax, Nova Scotia. Participants were invited via email to complete the online survey. Readability and clarity were assessed through pilot testing.Results
A total of 49 (55.7%) of 88 participants of the two studies completed the survey (22 [55%] of 40 participants from the Ebola vaccine study and 27 [56.3%] of 48 from the adjuvanted influenza vaccine study). Motivations that were most frequently ranked among participants' top three in both trials were (1) wanting to contribute to the health of others, (2) wanting to participate in something important, (3) wanting to contribute to the advancement of science, and (4) wanting to receive an incentive such as money or a tablet.Conclusions/Recommendations
Although media attention and financial compensation were more often cited by Ebola vaccine trial participants as a reason to participate, both altruistic and self-interested factors were important motivations for participants in their decision to participate in a phase 1 vaccine clinical trial. 相似文献6.
7.
《Vaccine》2016,34(38):4635-4641
BackgroundBroad use of monovalent Haemophilus influenzae type b (Hib) conjugate vaccines based on the capsular polysaccharide polyribosyl-ribitol phosphate (PRP), has significantly reduced invasive Hib disease burden in children worldwide, particularly in children aged <1 year. In Japan, PRP conjugated to tetanus toxoid (PRP-T) vaccine has been widely used since the initiation of public funding programs followed by a routine vaccination designation in 2013.MethodsWe compared the immunogenicity and safety of PRP conjugated to a non-toxic diphtheria toxin mutant (PRP-CRM197) vaccine with the PRP-T vaccine when administered subcutaneously to healthy Japanese children in a phase III study. Additionally, we evaluated the immunogenicity and safety profiles of a diphtheria–tetanus acellular pertussis (DTaP) combination vaccine when concomitantly administered with either PRP-CRM197 or PRP-T vaccines. The primary endpoint was the “long-term seroprotection rate”, defined as the group proportion with anti-PRP antibody titers ⩾1.0 μg/mL, after the primary series.ResultsLong-term seroprotection rates were 99.3% in the PRP-CRM197 group and 95.6% in the PRP-T group. The intergroup difference (PRP-CRM197 group – PRP-T group) was 3.7% (95% confidence interval: 0.099–7.336), demonstrating that PRP-CRM197 vaccine was non-inferior to PRP-T vaccine (p < 0.0001). Furthermore, the “short-term seroprotection rate” (anti-PRP antibody titer ⩾0.15 μg/mL) before booster vaccination was higher in the PRP-CRM197 group than in PRP-T. Concomitant administration of PRP-CRM197 vaccine with DTaP vaccine showed no differences in terms of immunogenicity compared with concomitant vaccination with PRP-T vaccine and DTaP vaccine. Although CRM197 vaccine had higher local reactogenicity, overall, both Hib vaccines had acceptable safety and tolerability profiles.ConclusionThe immunogenicity of PRP-CRM197 vaccine administered subcutaneously as a three-dose primary series in children followed by a booster vaccination 1 year after the primary series induced protective levels of Hib antibodies with no safety or tolerability concerns.Clinical trial registry: Registered on ClinicalTrials.gov: NCT01379846 相似文献
8.
《Clinical breast cancer》2020,20(1):80-86
BackgroundEpidermal growth factor receptor (EGFR) is frequently overexpressed in metastatic triple-negative breast cancer (mTNBC). One strategy for overcoming resistance to EGFR inhibition is concomitant inhibition of downstream signaling. The antidiabetic drug metformin inhibits both MAPK and PI3K/mTOR pathway signaling. We evaluated the combination of erlotinib and metformin in a phase 1 study of patients with mTNBC.Patients and MethodsPatients with mTNBC who had received at least one prior line of therapy for metastatic disease were eligible. Erlotinib dose was fixed at 150 mg daily. Metformin dose escalation was planned according to a 3 + 3 design. Dose-limiting toxicities (DLT) were assessed during the first 5 weeks of therapy. The primary objective was to determine the maximum tolerated dose of metformin with fixed-dose erlotinib. Secondary endpoints were response rate, stable disease rate, and progression-free survival.ResultsEight patients were enrolled. The median number of prior therapies for metastatic disease was 2.5 (range, 1-6). No DLT events were reported during the DLT assessment period. Most adverse events were grade 1/2. Grade 3 diarrhea despite maximum supportive care required dose reduction of metformin in one patient. Grade 3 rash led to study withdrawal in one patient. No grade 4 adverse events were reported. The best observed response was stable disease in 2 patients (25%). Median progression-free survival was 60 days (range, 36-61 days).ConclusionErlotinib and metformin were well tolerated in a population of pretreated mTNBC patients but did not demonstrate efficacy in this population. 相似文献
9.
目的:研究胃粘膜相关淋巴组织型(MALT)淋巴瘤MAPK和Stat3磷酸化与cyclinD1蛋白表达及其意义。方法:利用免疫组织化学方法检测了45例胃MALT淋巴瘤MAPK和Stat3磷酸化及cyclinD1蛋白的表达。结果:在胃MALT淋巴瘤中p-MAPK、p-Stat3及cyclinD1蛋白的阳性率分别为73.3%(33/45)、64.4%(29/45)和68.9%(31/45);低度恶性组p-MAPK和cyclinD1蛋白的阳性表达强度明显高于高度恶性组(P<0.01),而p-Stat3表达强度无明显差异(P>0.05);在低度和高度恶性胃MALT淋巴瘤中p-MAPK和cyclinD1蛋白的阳性信号强度均呈明显的正相关(r=0.6572和0.6823,P<0.01),而p-Stat3与cyclinD1蛋白表达未见明显相关性(r=0.1927,P>0.05)。结论:提示MAPK磷酸化在胃MALT淋巴瘤中发生及演进过程中起重要作用,但Stat3的磷酸化可能与该肿瘤的恶性演进关系不明显;在胃MALT淋巴瘤的发生与发展中,p-MAPK可诱导cyclinD1过度表达,从而促使该肿瘤细胞维持高增殖状态。 相似文献
10.
We performed an open, double-blind, and long-term study of vigabatrin (gamma-vinyl-GABA, GVG) in patients with treatment-resistant epilepsy who were receiving only one or at most two standard antiepileptic drugs (AEDs). The novel design included a parallel, double-blind, placebo-controlled phase that minimized the number of patients receiving placebo and allowed determination of the optimum dose of GVG for each patient before initiation of the double-blind phase. The study was divided into four phases. The first phase was a 6-week period of baseline observation. In the second phase, GVG was added openly to previous AEDs for 8 weeks. During the first 2 weeks of this phase, the dose of GVG was increased weekly and then, in the absence of adverse effects, was held constant for the next 6 weeks. At the end of this open phase, seizure frequency during the 6 weeks of constant treatment was compared with the baseline seizure frequency for each patient. Patients who experienced reduction greater than 50% in the frequency of any seizure type during the open phase were defined as responders. These responders were then entered into the third and double-blind phase, in which they were randomly allocated wither to continue active GVG treatment or placebo for 8 weeks. Thirty-three patients entered the study; 31 of 33 patients completed the initial open phase. Twenty patients achieved a reduction greater than or equal to 50% in the frequency of one or more seizure types and were eligible for the double-blind phase; 10 were randomized to continue GVG and 10 were randomized to placebo.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献