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111.
Summary This article reports TLC data (corrected Rf values; R f c values) of 170 commonly used pesticides which are regularly encountered in toxicological analysis. Silica gel was used as the stationary phase and three binary systems were chosen as solvents.  相似文献   
112.
[目的 ]了解朝鲜族的各种鼻部肿瘤的发病率并确定针对高发鼻部肿瘤的研究课题 .[方法 ]调查 1990年 1月到 1999年 10月之间在延边大学医学院附属医院病理科经活检确诊为鼻部肿瘤的全部患者的原始记录 .[结果 ]发现了 82例朝鲜族鼻部肿瘤患者 .其中 ,发病率最高的为乳头状瘤 ( 3 6/ 82 ) ,其次为鳞状上皮癌 ( 13 / 82 ) .[结论 ]朝鲜族鼻部乳头状瘤的发病率明显高于国内其它地区 .必须提高对鼻部乳头状瘤的诊断和治疗水平 ,并加快有关鼻部乳头状瘤和人类乳头状瘤病毒之间的关系的研究 .  相似文献   
113.
目的探讨囊肿切除、胆道重建治疗婴儿胆总管囊肿的疗效.方法1984年6月~1999年6月共有15例婴儿先天性胆总管囊肿患儿在我科接受了囊肿切除、胆道重建手术治疗,并对这些患儿进行了随访,随访资料包括症状、体征、B超.钡餐及肝功能检查.结果随访资料完整者12例,除1例术后3个月死于肝功能衰竭外,其余11例成活的患儿生长发育均正常;2例未行套叠瓣的患儿偶有上腹疼痛,但腹痛可自行缓解,钡餐检查见钡剂返流;全组病例肝功均正常,未见胆道结石、消化道溃疡、食道下端静脉曲张.结论囊肿切除、胆道重建治疗婴儿先天性胆总管囊肿可取得满意的疗效.  相似文献   
114.
血管内超声(IVUS)图像是观测血管内部结构的首选影像学手段,基于IVUS图像的内膜和中外膜边界的提取是实现冠脉粥样硬化精准诊断的前提和关键。针对IVUS图像结构复杂、对比度低、边界提取困难等问题,本研究提出一种基于改进TransUnet网络的分割方法。首先,针对IVUS图像边界提取难点,对边血管、血管分叉、导丝伪像、阴影等4种图像结构进行建模,并基于建模结果予以定向数据增强;而后,结合IVUS图像的环状结构分布特点,在TransUnet网络中提出了Polar-bias归纳偏置的策略,并对IVUS图像进行像素级的分类;最后,基于分类结果优化GVF snake模型的外力场,进而提取IVUS图像的内膜和中外膜边界。采用国际标准IVUS图像数据集(两组不同中心频率,共512幅图像)对算法进行评测,引入JMard距离(JM),Hausdorff距离(HD)和面积差异百分比(PAD)等3个评测指标,在数据集A中JM为0.87, HD为0.87, PAD为0.18,数据集B中JM为0.91, HD为0.25, PAD为0.08。实验结果表明,所提出的算法在两组数据集的内膜及中外膜提取问题中的表现均...  相似文献   
115.
提出基于不完整数据的IHB-LightGBM(Improved Hyperband-Light Gradient Boosting Machine)心脏病预测模型。首先,在Hyperband算法超参数采样的基础上引入了权重值,并通过蓄水池法按特征权重对其进行排序,从而筛选出最优参数以提高算法的参数寻优能力;其次,针对心脏病数据样本小且属性缺失的问题,使用K近邻算法对不完整数据进行缺失值插补,再将处理得到的完整数据进行归一化,使数据映射至0~1范围内;最后,对LightGBM采用改进后的IHB优化算法进行全局参数寻优,建立IHB-LightGBM心脏病预测模型。使用UCI心脏病数据集进行实验,结果表明IHB算法的参数寻优效果优于贝叶斯、随机搜索等优化算法,IHB-LightGBM模型在各项评价指标也上明显高于随机森林、极端随机树等算法,可以获得更快的预测速度和更高的预测精度。  相似文献   
116.
《Genetics in medicine》2023,25(4):100001
PurposePersonalized information is paramount to patient-centered communication and decision-making regarding risk management in hereditary cancer syndromes. This systematic review identified information needs of individuals from families harboring BRCA pathogenic variants and compared findings based on gender (women vs men) and clinical characteristics (patients with cancer vs previvors and BRCA heterozygotes vs untested relatives).MethodsWe screened 8115 studies identified from databases and citation searching. The quality of selected studies was assessed using the Mixed Methods Appraisal Tool. Narrative synthesis was conducted based on content analysis.ResultsFrom 18 selected studies including 1063 individuals, we identified 9 categories of information needs. Risk of bias in the selected studies was moderate. Men, untested relatives, and racial and ethnic minorities were underrepresented. Frequently required information was personalized cancer risk and risk-reducing strategies, including decision-making, family implications of hereditary cancers, psychological issues, and cascade testing. Subgroup analyses showed that information needs depended on gender, personal cancer history, and cascade testing in relatives.ConclusionWe identified comprehensive and detailed informational needs of individuals from families harboring BRCA pathogenic variants and gaps in international guidelines. Needs for personalized information varied based on gender, health, and genetic testing status. Findings of this study have implications for genetic counseling, tailoring educational materials, and personalizing interventions.  相似文献   
117.
The changes in the anthropometric data and urine steroid metabolites caused by regular training in children in two age groups (11 and 14 years old) were investigated. The skinfolds of older girls participating in regular athletic, swimming or soccer training were thinner compared with age-matched control groups (P < 0.01) and their body mass and constitution were lower (P < 0.05). In the other groups no significant differences were observable in the anthropometric parameters. The trained children in all groups had significantly higher exercise times on the cycle ergometer (P < 0.01, in young boysP < 0.05). The strength of their hands was lower in three trained groups: in younger boys (P < 0.05), in younger girls (P < 0.01) and in older girls (right handP < 0.01, left handP < 0.05). The urinary excretion of androsterone (P < 0.02), 11-ketopregnanetriol (P < 0.01) and pregnenetriol (P < 0.02) was decreased in the older trained girls; pregnenetriol was increased in younger boys (P < 0.05). Urinary excretion of cortisol metabolites was increased in trained boys [in younger boys: tetrahydrocorticosterone (P < 0.05) and 20-hydroxycortisol (P < 0.05); in older boys allotetrahydrocortisol (P < 0.02), cortisol (P < 0.05) and 20-hydroxycortisol (P < 0.05)]. There were no significant differences in the younger girls. In the trained older girls urinary excretion of cortisol metabolites was decreased: tetrahydrocortisone (P < 0.02), allotetrahydrocorticosterone (P < 0.01), tetrahydrocortisol (P < 0.05), -cortolone (P < 0.01), cortisol (P < 0.02), 6-hydroxycortisol (P < 0.01) and 20-hydroxycortisol (P < 0.05). A multivariate analysis of the data from the trained groups and sedentary, age-matched control groups showed that regular training has a significant effect on steroid excretion.  相似文献   
118.
①目的 调查长途汽车司机有关艾滋病( A I D S)的知识及对 A I D S的态度,为进一步在该人群中开展艾滋病知识的宣传教育、制订有关预防措施提供依据。②方法 对青岛市 3 个长途汽车运输公司以单纯随机抽样方法抽取74 名进行调查,调查表采用匿名自填方式。③结果 大多数调查对象对艾滋病的病原体、传播途径、临床表现及潜伏期病人的危险性认识不足,而对艾滋病的有关知识感兴趣,并希望通过各种途径加以了解。④结论 长途汽车司机对有关艾滋病的知识了解较少,应加强对该人群有关艾滋病知识的宣传教育。  相似文献   
119.
Differing pathological haemodynamics in cardiac malformations lead to varying modes and timings of presentation. This study identifies historical trends in presentation of congenital heart disease in a population-based study. All patients diagnosed as having congenital heart disease in Malta between 1960–1994 were included (n = 868). Analysis was carried out on trends in referral sources, modes of presentation and birth prevalence. The number of patients diagnosed with congenital heart disease increased over the period under study. For both patients not requiring intervention (n = 283) and those requiring intervention (n=585), the proportion diagnosed prior to hospital discharge increased (p 0.005). There was a decreasing trend for general practitioners to refer cases (p < 0.0001), and an increasing trend for paediatricians to refer such patients (p 0.0003). The commonest presentation to the general practitioner was an incidental finding (92%), while paediatricians referred more patients for cyanosis or heart failure (p 0.005). For lesions not requiring intervention, the commonest lesion referred was ventricular septal defect from all sources. For lesions requiring intervention, the commonest lesion detected prior to hospital discharge was tetralogy of Fallot. Atrial septal defects were the commonest lesions detected after discharge by both paediatricians and general practitioners. An increase in the proportion of hospital diagnoses is attributed to increasing rate of hospital delivery, and greater training and experience in doctors performing neonatal examinations prior to discharge. Patients diagnosed after discharge are increasingly diagnosed by paediatricians due to an increasing pool of paediatricians and better parent awareness and education.  相似文献   
120.
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