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《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   
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《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   
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《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   
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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   
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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   
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112例脑动脉系统微栓子监测的临床研究   总被引:1,自引:1,他引:0  
目的 研究脑动脉系统微栓子 (MES)的产生机制及其相关因素。方法 将 112例 MES监测的临床资料进行总结分析。结果 本组微栓子检出率为 33.93% ,且全部见于有明显脑卒中症状者 ;脑梗死 MES检出率为35 .87%且以原发性大面积梗死为主 ;MES阳性与病程有明显相关 ,病程 <72 h易检出微栓子 ,阳性率为 4 7.72 % ;颅内血管狭窄是微栓子产生的主要原因 ;颈动脉异常与正常组微栓子出现率无明显差异 ,但发现本组病例中微栓子出现以左侧为主 ,与颈动脉病变部位一致率为 5 5 .5 5 % ;确定微栓子来源于有病变的颅外颈动脉 2例 ,来源于有病变的颅内颈动脉系 5例 ,来源于同时伴有颅内外血管病变 12例 ,表明颅内外动脉同时伴有病变时微栓子检出率增高 ;MES的阳性率与血液成分无相关性 ,但在血液成分异常组中血粘度增高以及血小板聚集降低 MES阳性率明显增高。结论 脑动脉系统中监测到微栓子说明患者有活动的栓子来源 ,易发生或复发脑梗死 ,TCD能正确的监测、判断脑循环中微栓子 ,确定其发生率、性质、来源以及与疾病的联系  相似文献   
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