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1.
目的 应用决策树C5.0和Logistic回归分别建立产后压力性尿失禁的风险预测模型,比较2种模型的预测效果。方法 选取2020年7月—2021年1月于山东省某三级甲等医院产后康复门诊就诊的女性505例,采用问卷调查法筛查产后压力性尿失禁并获取产妇的一般资料,采用生物反馈治疗仪评估产妇的盆底肌电值。将所有数据按照7∶3的比例建立训练集与测试集(训练集450例,测试集145例),运用决策树C5.0及Logistic回归建立产后压力性尿失禁的风险预测模型,采用特异度、灵敏度、准确率、阴性预测值、阳性预测值、约登指数和受试者工作特征曲线的曲线下面积对2种模型的预性能进行比较。结果 在训练集中,决策树C5.0与Logistic回归的准确度分别为98.9%、85.6%,灵敏度为94.7%、48.7%,特异度为100.0%、95.4%,阳性预测值为100.0%、74.0%,阴性预测值为98.6%、87.4%,约登指数为94.7%,44.1%,受试者工作特征曲线的曲线下面积为0.974、0.721,2种模型的受试者工作特征曲线的曲线下面积相比较差异具有统计学意义(P<0.05);在测试集中,决策树C5.0和Logistic回归的准确度为87.6%、82.8%,灵敏度为78.6%、46.4%,特异度为89.7%、91.5%,阳性预测值为64.7%、56.5%,阴性预测值为94.6%、87.7%,约登指数为68.3%、37.9%,受试者工作特征曲线的曲线下面积为0.842、0.689,2种模型的受试者工作特征曲线的曲线下面积相比较差异具有统计学意义(P<0.05)。结论 决策树C5.0对产后压力性尿失禁的预测性能优于Logistic回归。  相似文献   
2.
ObjectiveTo develop a prediction model for survival of patients with coronary artery disease (CAD) using health conditions beyond cardiovascular risk factors, including maximal exercise capacity, through the application of machine learning (ML) techniques.MethodsAnalysis of data from a retrospective cohort linking clinical, administrative, and vital status databases from 1995 to 2016 was performed. Inclusion criteria were age 18 years or older, diagnosis of CAD, referral to a cardiac rehabilitation program, and available baseline exercise test results. Primary outcome was death from any cause. Feature selection was performed using supervised and unsupervised ML techniques. The final prognostic model used the survival tree (ST) algorithm.ResultsFrom the cohort of 13,362 patients (60±11 years; 2400 [18%] women), 1577 died during a median follow-up of 8 years (interquartile range, 4 to 13 years), with an estimated survival of 67% up to 21 years. Feature selection revealed age and peak metabolic equivalents (METs) as the features with the greatest importance for mortality prediction. Using these 2 features, the ST generated a long-term prediction with a C-index of 0.729 by splitting patients in 8 clusters with different survival probabilities (P<.001). The ST root node was split by peak METs of 6.15 or less or more than 6.15, and each patient’s subgroup was further split by age or other peak METs cut points.ConclusionApplying ML techniques, age and maximal exercise capacity accurately predict mortality in patients with CAD and outperform variables commonly used for decision-making in clinical practice. A novel and simple prognostic model was established, and maximal exercise capacity was further suggested to be one of the most powerful predictors of mortality in CAD.  相似文献   
3.
背景与目的:胃肠道间质瘤(gastrointestinal stromal tumor,GIST)的生物危险度可分为极低危、低危、中危和高危,术前就危险度进行准确预判对临床制订诊疗方案至关重要。探讨基于超声征象的决策树模型在预测GIST危险度中的应用价值。方法:收集福建医科大学附属协和医院2016年12月—2020年12月收治的206例GIST患者,建立决策树模型,并判断模型预测的准确度。结果:低危、中危和高危3组间病灶长径、短径/长径(short diameter/long diameter,S/L)、肿瘤部位、回声高低、回声均匀性、边界、形态、是否坏死囊变和血流信号的差异均有统计学意义(P均<0.05)。以病灶长径、肿瘤部位、回声均匀性及形态为节点建立的决策树模型预测的准确度为72.33%,其中低危组和高危组预测的准确度可高达80.90%和93.90%。结论:以超声特征为主要指标构建的决策树模型在预测GIST危险度中具有较高的应用价值。  相似文献   
4.
Hepatitis B virus (HBV) DNA is detectable in the nails and hair of patients with chronic HBV infection. However, it remains unclear whether HBV DNA can be detectable in the nails and hair of patients with acute HBV infection. We encountered two cases of children with acute HBV infection. HBV DNA in the nails and hair from the two children was evaluated by real-time PCR. To clarify the characteristics of HBV DNA, full-length HBV genome sequencing and phylogenetic tree analysis were performed. The levels of serum HBV DNA in children of cases 1 and 2 at day 0 were 7.6 Log IU/mL and 7.4 Log IU/mL, respectively. Nail HBV DNA was detected in both children (case 1: 4.6 Log IU/mL at day 0, case 2: 5.5 Log IU/mL at day 14). Moreover, hair HBV DNA was detectable in case 2 (4.0 Log IU/mL at day 14). Serum HBV DNA became undetectable within approximately 3–4 months after the first hospital visit. After the resolution of HBV viremia, nail and hair HBV DNA became undetectable. The sequence analysis of serum, nail and hair HBV DNA showed the same HBV genotype in each case (case1: genotype C, case 2: genotype A). In case 1, 3 nucleotides were different in the full-genome HBV sequence between the serum and nails. In case 2, the full-genome HBV sequences were identical among the serum, nails and hair. In conclusion, HBV DNA was detectable in nails and hair of children with acute HBV infection.  相似文献   
5.
Background: Even with the fantastic successes of direct-acting antivirals (DAA) in the treatment of Hepatitis CVirus (HCV) infection, natural drug resistance remains a challenging obstacle for their impacts. The data regardingprotease inhibitors (PIs) resistance in Iran population are limited. The aim of this study was to investigate the variationsin NS3 protease of HCV from non-responder patients. Methods: In this cross-sectional study, 14 HCV infected patientswith genotype 1(N=5) and 3(N=9) who have not responded to Interferon-related regime were enrolled from LiverClinic, Shiraz. The NS3 protease region was amplified by Nested-PCR followed by product gel extraction. Besides,some amplified protease regions were cloned into a cloning vector to improve the sensitivity of mutation detection.Both crude and cloned sequences were then introduced into sequencing. The obtained sequences were compared withthe NS3 reference sequences and analyzed by Geno2pheno available software to find possible substitutions. In theend, the phylogenetic tree was constructed. Results: Among variations responsible for PIs resistance, only one out of14 (7%) sample who was infected with genotype 1a, harbored R117C+N174S double mutation, which causes reducedsusceptibility to Telaprevir. Any another resistance mutation was not found among the studied population. The mostfrequent substitutions were determined as I52M(N=9), S102A(N=9), S166A(8) and V170I(8) for genotype 3a, andF147S/A(4) for genotype 1. However, some uncharacterized substitutions on scored position, including I132L(N=1),I170V(N=3) and N174S(N=2) were also determined among sequences. Phylogenetic analysis demonstrated that theprotease region has enough power to correctly classify enrolled samples into relevant clusters on the tree. There were 2,3 and 9 cases of sub-genotypes 1a, 1b, and 3a, respectively. Conclusion: A low frequency of PIs resistance mutationsin our HCV infected population is a hopeful point of starting these drugs in HCV infected patients.  相似文献   
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7.
目的 探讨临床决策树法与积分模型法对结核性胸膜炎的诊断效能。方法 采用前瞻性随机对照研究方法,以2019年1月1日—2019年6月30日武汉市肺科医院收治的胸腔积液患者为研究对象。符合入组标准的胸腔积液患者随机入组临床决策树法组和积分模型法组,分别采用两种综合诊断模型进行诊断,对比两组方法的诊断效能。结果 临床决策树组共纳入127例患者,其中男性90例,女性37例,年龄18~88岁,平均(49.33±19.63)岁,最后诊断结核性胸膜炎108例,非结核性胸膜炎19例;积分模型组共纳入120例患者,其中男性89例,女性31例,年龄13~84岁,平均(46.41±20.01)岁,最后诊断结核性胸膜炎94例,非结核性胸膜炎26例。临床决策树法诊断结核性胸膜炎的敏感度57.4%,特异度78.9%,阳性预测值93.9%,阴性预测值24.6%,诊断准确率60.6%;积分模型法诊断结核性胸膜炎的敏感度75.5%,特异度96.2%,阳性预测值98.6%,阴性预测值52.1%,诊断准确率80.0%。结论 积分模型法诊断结核性胸膜炎敏感度、特异度及诊断准确率均高于临床决策树法,方法简单,可推广应用于结核性胸膜炎的临床诊断。  相似文献   
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9.
Porcine deltacoronavirus has caused great economic losses in the swine industry worldwide. In this study, we carried out the first detection, sequencing and characterization of this virus in Mexico. We analysed 885 rectal samples by multiplex RT‐PCR to determine coinfections. In addition, the Spike gene was amplified, sequenced and analysed phylogenetically. We found 85 positive samples for porcine deltacoronavirus, representing 9.6% of the total samples, and we determined that the most frequent coinfection was with porcine epidemic diarrhoea virus (54.1%). Four sequences of Mexican isolates were most closely related to those of the United States. The antigenic regions and the glycosylation site of the strains obtained coincide with those previously reported. This relationship is probably related to the commercial exchange of pigs between the US and Mexico and the geographical proximity of these two countries.  相似文献   
10.
As one of emerging porcine viruses, atypical porcine pestivirus (APPV) was found in three continents since it emerged in 2015. It is now thought as the causative agent for congenital tremor type A‐II in piglets. At the end of 2017, two APPV strains were identified from piglets with congenital tremor in Guangxi and Yunnan, China. The genome of APPV GX04/2017 strain was so far determined to be 11,534 nucleotides (nt) in length and contains a single open reading frame (ORF) encoding a polyprotein comprising 3,635 amino acids. Comparative analysis of ORF, Npro, E2, and NS3 gene sequences revealed that the APPV GX04/2017 strain shares nucleotide sequence identities of 82.8%–92.8% with other APPV strains, while YN01/2017 strain is 79.4%–97.4% homology to the others. Phylogenetic analysis showed that the APPV GX04/2017 and YN01/2017 are two novel APPV strains with the highest homology to each other, and relative high similarity to the APPV 000515 and JX‐JM01 strains in genome sequence. The current findings provide updated information about APPV epidemiology and divergence in China, which would certainly help to establish reliable diagnosis and surveillance programs for APPV.  相似文献   
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