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61.
目的塑料地板胶制鼠迹板测试居民区住宅外鼠密度可行性。方法在居民区住宅外分3种生境进行试验,次日观察鼠迹板阳性率、损坏率和丢失率。结果普通地面平均损坏率为49.1%,楼梯、外长廊为16.3%,楼顶、露台损坏率为10.0%。经秩和检验,普通地面与另外2种生境之间的鼠迹板损坏差别有统计学意义(U=5.72和6.37,P〈0.001),而楼梯、外长廊与楼顶、露台之间比较鼠迹板损坏差别无统计学意义(U=0.97,P〉0.05)。结论鼠迹板适合监测鼠情,测试居民区外环境鼠密度有待研究。 相似文献
62.
63.
目的针对一例无症状的8号染色体三体的患者,研究其8号染色体的来源机制和作用机制。方法利用患者外周血进行淋巴细胞培养及G显带技术分析,以确定淋巴细胞核型;利用患者外周血总DNA进行SNP微阵列技术分析,以确定各类有核细胞的分子核型。结果患者外周血淋巴细胞核型为47,XX,+8;患者外周血各种有核细胞总DNA基因型为47,XX,+8。结论确诊患者外周血有核细胞的核型均为47,XX,+8,并且多出来的那条染色体可能由于第二次减数分裂不分离而导致的,尚不能明确该患者没有明显临床症状的机制。 相似文献
64.
65.
目的:探讨Geminin基因沉默对人脑胶质瘤细胞恶性生物学行为的影响及可能的发生机制.方法:选取南通大学附属医院脑外科2018-2019年手术切除的20例神经胶质瘤患者的新鲜标本,qRT-PCR结合基因表达谱数据动态分析(gene expression profilling interactive analysis,G... 相似文献
66.
Jie LIU Xin-Xing FENG Yan-Feng DUAN Jun-Hao LIU Ce ZHANG Lin JIANG Lian-Jun XU Jian TIAN Xue-Yan ZHAO Yin ZHANG Kai SUN Bo XU Wei ZHAO Ru-Tai HUI Run-Lin GAO Ji-Zheng WANG Jin-Qing YUAN Xin HUANG Lei SONG 《老年心脏病学杂志》2022,19(5):367
BACKGROUNDThree-vessel disease (TVD) with a SYNergy between PCI with TAXus and cardiac surgery (SYNTAX) score of ≥ 23 is one of the most severe types of coronary artery disease. We aimed to take advantage of machine learning to help in decision-making and prognostic evaluation in such patients.METHODSWe analyzed 3786 patients who had TVD with a SYNTAX score of ≥ 23, had no history of previous revascularization, and underwent either coronary artery bypass grafting (CABG) or percutaneous coronary intervention (PCI) after enrollment. The patients were randomly assigned to a training group and testing group. The C4.5 decision tree algorithm was applied in the training group, and all-cause death after a median follow-up of 6.6 years was regarded as the class label.RESULTSThe decision tree algorithm selected age and left ventricular end-diastolic diameter (LVEDD) as splitting features and divided the patients into three subgroups: subgroup 1 (age of ≤ 67 years and LVEDD of ≤ 53 mm), subgroup 2 (age of ≤ 67 years and LVEDD of > 53 mm), and subgroup 3 (age of > 67 years). PCI conferred a patient survival benefit over CABG in subgroup 2. There was no significant difference in the risk of all-cause death between PCI and CABG in subgroup 1 and subgroup 3 in both the training data and testing data. Among the total study population, the multivariable analysis revealed significant differences in the risk of all-cause death among patients in three subgroups.CONCLUSIONSThe combination of age and LVEDD identified by machine learning can contribute to decision-making and risk assessment of death in patients with severe TVD. The present results suggest that PCI is a better choice for young patients with severe TVD characterized by left ventricular dilation.Coronary artery disease (CAD) is the leading cause of death and disability worldwide.[1] Three-vessel disease (TVD) is the most severe form of CAD and is characterized by significant stenosis in all three major coronary arteries. The application of myocardial revascularization techniques, including coronary artery bypass grafting (CABG) and percutaneous coronary intervention (PCI), has significantly improved the clinical outcomes of patients with severe CAD. CABG has traditionally been the standard therapy for complex coronary lesions, including TVD.[2] In recent years, with the advancements in PCI technology and the accumulation of operators’ experience, the incidence of periprocedural and long-term adverse events of PCI has substantially decreased, and PCI has been gradually applied in the treatment of TVD.[3,4] Current guidelines recommend use of the SYNergy between PCI with TAXus and cardiac surgery (SYNTAX) score and diabetes status to guide the revascularization strategy for patients with TVD.[5,6] Current practice guidelines do not recommend PCI for patients with TVD with a SYNTAX score of ≥ 23. However, using the SYNTAX score to guide clinical decision-making between PCI and CABG remains controversial, and its reasonability has been questioned since a newly published meta-analysis showed no significant association between the SYNTAX score and the comparative effectiveness of PCI and CABG.[7] Moreover, the SYNTAX score is a quantitative indicator of the anatomical complexity of TVD and does not include clinical variables that may have significant effects on the patient’s prognosis. Whether some patients with specific clinical characteristics can obtain a comparable or even greater survival benefit from PCI than from CABG is unclear. Moreover, risk assessment for patients with TVD after revascularization therapy remain challenging.[8–10]Machine learning has recently emerged as an important research method and has been successfully applied in many scientific fields, including clinical medicine.[11–13] The decision tree algorithm, a common approach in machine learning, can handle non-linearity, heterogeneous effects, and high-dimensional features and partition a trial population into subgroups characterized by multiple simultaneous characteristics.[14] In the present study involving a large cohort of patients with TVD with a SYNTAX score of ≥ 23, we employed a decision tree algorithm to generate specific subgroups, compared the long-term prognosis between patients who underwent PCI or CABG in each subgroup, and conducted a comparative analysis of the long-term prognosis between subgroups generated by machine learning. We evaluated whether machine learning can help in selecting the optimal revascularization method and assessing risk in patients with severe TVD. 相似文献
67.
目的了解宝鸡市乙型肝炎发病情况及流行病学特征,为制定控制策略和措施提供科学依据。方法采用描述流行病学方法,对2000-2007年宝鸡市乙型肝炎疫情资料进行统计分析。结果2000~2004年各年龄组发病率呈上升趋势,2005年起各年龄组发病率均有所下降,特别是14岁以下儿童发病率下降比较明显。农村发病明显高于城区。发病构成中农民所占比例最高,占乙型肝炎发病总数的51.85%,幼托儿童和散居儿童发病构成呈下降趋势。结论14岁以下儿童乙肝免疫防治策略已初见成效。应在加强新生儿及儿童乙型肝炎免疫接种工作的同时,加大对中青年及农村劳动人口乙型肝炎疫苗的免疫接种工作。 相似文献
68.
中医学重视人体正气在恶性肿瘤防治中的关键作用,强调"调和阴阳,以平为期",刘嘉湘教授创建"以人为本"、"顾护正气"为核心特征的"扶正治癌"学术体系,强调调控机体内在抵抗力(含免疫功能)以防治恶性肿瘤;肿瘤免疫治疗的疗效已经在泛癌种范围内得以确认,被认为是"最有可能治愈癌症"的疗法.从肿瘤免疫学角度深入研究人体"正气"的... 相似文献
69.
目的 探讨增殖细胞核抗原在不同病理类型髓母细胞瘤中的表达差异和临床意义.方法 对34例髓母细胞瘤(经典型61.8%,促硬纤维增生型38.2%)进行增殖细胞核抗原的免疫组化染色,测定不同类型髓母细胞瘤的增殖细胞核抗原指数.结果 经典型髓母细胞瘤的增殖细胞核抗原指数为(81.45±9.29)%,促硬纤维增生型髓母细胞瘤增殖细胞核抗原指数为(39.86±8.37)%,不同髓母细胞瘤亚型的增殖细胞核抗原指数值存在显著差异(P<0.01).结论 增殖细胞核抗原的表达差异,为不同亚型髓母细胞瘤的生物行为学差异提供了病理学依据,增殖细胞核抗原指数可以作为髓母细胞瘤恶性程度及患者预后判断指标. 相似文献
70.
保留幽门和迷走神经的胃部分切除手术对早期胃癌的疗效观察 总被引:2,自引:0,他引:2
目的 探讨保留幽门和迷走神经的胃部分切除手术(PPG)对早期胃癌的疗效.方法 回顾性分析1995年8月至2005年12月对52例早期胃癌患者行保留幽门和迷走神经的胃部分切除术(PPG组)的临床资料和随访结果;并与同期行远端胃切除术伴淋巴结清除的159例早期胃癌患者(对照组)的临床资料进行比较.结果 PPG组早期胃癌的淋巴结转移率为9.6%,对照组淋巴结转移率为17.0%;两组比较,差异无统计学意义(P>0.05).PPG组淋巴结清除范围D1为25%,D1+α(α=No.7)为25%,D1+β(β=No.8a和No.9)为34.6%,D2为15.3%;对照组121例(76.1%)D2以下,33例(20.7%)D2,5例(3.1%)D3;两组比较,差异无统计学意义(P>0.05).术后累计5年生存率PPG组为92.3%,对照组93.1%,两组差异无统计学意义(P=0.881).其中淋巴结不同清除程度的累计5年生存率PPG组:D1为100%,D1+α为92.3%,D1+β为88.9%,D2为87.5%;对照组:D1为92.3%,D1+α为93.3%,D1+β为91.7%,D2为93.9%;两组比较,差异无统计学意义(P>0.05).PPG组术后的复发率为5.7%,对照组则为5.6%,两组差异无统计学意义(P>0.05).结论 PPG对于早期胃癌的治疗是有效的. 相似文献