全文获取类型
收费全文 | 22008篇 |
免费 | 1876篇 |
国内免费 | 1731篇 |
专业分类
耳鼻咽喉 | 157篇 |
儿科学 | 188篇 |
妇产科学 | 204篇 |
基础医学 | 2603篇 |
口腔科学 | 319篇 |
临床医学 | 3012篇 |
内科学 | 3296篇 |
皮肤病学 | 249篇 |
神经病学 | 1062篇 |
特种医学 | 759篇 |
外国民族医学 | 16篇 |
外科学 | 2204篇 |
综合类 | 3947篇 |
现状与发展 | 5篇 |
一般理论 | 1篇 |
预防医学 | 1265篇 |
眼科学 | 713篇 |
药学 | 2457篇 |
23篇 | |
中国医学 | 1153篇 |
肿瘤学 | 1982篇 |
出版年
2024年 | 81篇 |
2023年 | 377篇 |
2022年 | 1026篇 |
2021年 | 1170篇 |
2020年 | 879篇 |
2019年 | 683篇 |
2018年 | 741篇 |
2017年 | 750篇 |
2016年 | 682篇 |
2015年 | 1063篇 |
2014年 | 1297篇 |
2013年 | 1115篇 |
2012年 | 1689篇 |
2011年 | 1778篇 |
2010年 | 1087篇 |
2009年 | 819篇 |
2008年 | 1130篇 |
2007年 | 1087篇 |
2006年 | 1146篇 |
2005年 | 983篇 |
2004年 | 738篇 |
2003年 | 701篇 |
2002年 | 617篇 |
2001年 | 492篇 |
2000年 | 567篇 |
1999年 | 557篇 |
1998年 | 371篇 |
1997年 | 316篇 |
1996年 | 229篇 |
1995年 | 226篇 |
1994年 | 219篇 |
1993年 | 119篇 |
1992年 | 146篇 |
1991年 | 147篇 |
1990年 | 93篇 |
1989年 | 100篇 |
1988年 | 81篇 |
1987年 | 88篇 |
1986年 | 65篇 |
1985年 | 42篇 |
1984年 | 42篇 |
1983年 | 28篇 |
1982年 | 19篇 |
1981年 | 10篇 |
1980年 | 7篇 |
1979年 | 12篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
71.
目的 对医疗机构中药制剂创新和持续发展能力进行综合评价,为行政管理部门决策及各医院中药制剂可持续发展提供参考。方法 以浙江省133家医疗机构中药制剂调研数据为对象,利用层次分析法构建医疗机构中药制剂创新和持续发展能力评价体系,通过反向传播神经网络构建中药制剂室/中心评价体系预测模型。结果 构建的医疗机构中药制剂创新和持续发展能力评价指标体系包含4项二级指标以及19项三级指标,其中研发品种数、超百万品种数、注册品种数、研发方式、制剂室面积指标的权重值较高,分别为 0.15758、0.12928、0.09343、0.07879和0.07458。熵权法结合层次分析法的指标权重构建反向传播神经网络,Levenberg-Marquardt算法和Scaled Conjugate Gradient算法训练模型总体相关系数分别为0.98983和0.9348。结论 本研究构建了一个科学有效的医疗机构中药制剂创新和持续发展能力综合评价体系,可实现对医疗机构中药制剂综合能力的预测评价。 相似文献
72.
目的:调查重庆地区梅毒螺旋体基因亚型的分布,初步探讨基因亚型与临床相关性。方法:收集2010年6月至2013年10月重庆地区421例梅毒标本,用巢式PCR检测梅毒螺旋体DNA多聚酶I基因(DNA polymerase I gene,polA),然后扩增阳性标本酸性重复蛋白基因(acid repeat protein,arp)和苍白密螺旋体重复家族基因(treponema pallidum repeat,tpr)及TP0548基因,分别根据Pillay标准基因分型和三基因分型法进行分型,利用双侧Fisher’s exact test进行数据统计分析,初步探讨不同基因亚型与血清固定、梅毒复发和吉海反应的相关性。结果:163例标本polA PCR检测阳性,arp、tpr基因和TP0548基因亚型分别以14型、d型和f型为主。正规驱梅治疗12月后,32例患者血清固定,其中tpr基因d型(11例)、a和b型(各2例)和f型(1例);3例患者梅毒复发,其中TP0548基因c型(2例)和f型(1例);8例发生吉海反应,其中14f/f(4例),14d/f(3例)和未分型(1例)。结论:重庆地区梅毒螺旋体以14、d和f型为优势型。梅毒血清固定可能与tpr基因b型相关,14f/f基因型的二期梅毒患者易发生苄星青霉素治疗后的吉海反应。 相似文献
73.
目的:了解男男性行为者(men who have sex with men,MSM)在参加暴露前预防用药(pre-exposure prophylaxis,PrEP)临床试验中是否存在性行为去抑制化现象及其影响因素。方法:采用非概率抽样法招募并筛选出108名MSM,随机分为77名服用药物组和31名空白对照组,第12、24、36、48周进行临床随访和问卷调查,问卷调查主要包括社会人口学特征,艾滋病相关知识、态度和行为等相关情况。采用单因素和多因素的广义估计方程分析MSM在参与PrEP中是否存在性行为去抑制化现象及其影响因素。结果:药物服用组MSM在参与PrEP的第12、24、36、48周的性伴个数中位数分别为1(0,6)、1(0,6)、1(0,10)、1(0,3)、1(0,3),高危性行为次数中位数分别为1(0,26)、1.5(0,8)、1(0,12)、1(0,9)、2(0,30);空白对照组性伴个数中位数分别为1(0,21)、1(0,2)、1(0,3)、1(0,3)、1(0,3),高危性行为次数中位数分别为1(0,9)、1(0,6)、0.5(0,15)、0(0,10)、1(0,10);多因素广义估计方程分析发现MSM在参与PrEP过程中性伴个数及高危性行为次数均没有发生改变(Z=-0.24,P=0.811;Z=0.93,P=0.355),性行为方式为“1”和“0.5”的较性行为方式为“0”的拥有更多的性伴(Z=2.47,P=0.014;Z=2.24,P=0.025);发生过商业性行为的MSM较没有发生过的拥有较少的性伴和高危性行为(Z=-2.82,P=0.005;Z=-2.28,P=0.023);已婚较离异MSM发生较少的高危性行为次数(Z=-2.34,P=0.019)。结论:本研究中暂未发现PrEP中存在性行为去抑制化现象,性行为方式为“1”和“0.5”的MSM拥有较多性伴,是后期随访中的重点管理人群。还需进一步加强对艾滋病相关知识的科普。 相似文献
74.
75.
76.
Rong-chang Chen Gui-bo Sun Li-jiao Xu Xu Zhang Wen-ying Zeng Xiao-bo Suna 《中草药(英文版)》2022,14(1):70-78
Objective: This study was designed to investigate the protective effects of didymin (Did) on doxorubicin (DOX)-induced cardiotoxicity.
Methods: After pretreatment with Did (2, 4, 8 mg/kg intraperitoneal i.p.) for 7 d, the male C57 mice were injected with single dose of DOX (20 mg/kg i.p.). The cardioprotective effect of Did was observed on the 7th day after DOX treatment.
Results: DOX delayed body growth and caused cardiac tissue injury, oxidative stress, and mitochondrial dysfunction. Similar experiments in H9C2 cardiomyocytes showed that DOX reduced cell viability, increased generation of reactive oxygen species (ROS) and fragmentation of DNA, decreased mitochondrial membrane potential, and induced cardiomyocyte apoptosis. However, all of these adverse effects were suppressed by Did pretreatment. Did increased protein expression of glutamate-L-cysteine ligase catalytic subunit (GCL), heme oxygenase 1 (HO-1), and nuclear factor erythroid 2-related factor 2 (Nrf2). Besides, Did also induced activation of PI3K/AKT.
Conclusion: These findings indicated Did prevented DOX-induced cardiac injury and apoptosis via activating PI3K/AKT/Nrf2 signaling pathway. 相似文献
77.
大鼠视神经钳伤后外侧膝状体细胞损伤的研究 总被引:8,自引:1,他引:8
目的 探讨大鼠视神经钳伤后 ,外侧膝状体 (lateralgeniculatebody,LGB)细胞的损伤情况。方法 用 4 0g视神经损伤钳 ,压迫Sprague Dawley(SD)大鼠双侧视神经 30s,制成视神经部分定量损伤的动物模型。对LGB连续梯度切片 ,7d后用末端脱氧核苷酸转移酶介导的dUTP缺口末端标记法 (teriminaldeoxynucleotidyltransferase mediateddUTPnickend labeling ,TUNEL)对LGB细胞进行凋亡检测。 1个月后通过免疫组化染色技术 ,用兔抗鼠神经丝 (neurofilament,NF)单克隆抗体对LGB的神经元进行检测。同时经视觉中枢注入荧光染料颗粒蓝 ,对LGB细胞进行逆行荧光标记 ,在 70 0nm波长荧光显微镜下对连续切片的LGB标记细胞进行平均密度计数 ,并与对照组比较。结果 TUNEL法染色证实LGB细胞发生凋亡。对照组神经丝免疫组化染色呈清晰的条索状 ,而实验组明显减少。对照组LGB细胞密度均值为 (5 172± 2 4 8)个 /mm2 ,而损伤组LGB细胞密度均值为 (414 4± 6 1)个 /mm2 ,两组比较差异有非常显著意义 (t=8 995 ,P <0 0 1)。结论 在大鼠视神经钳伤后 ,LGB细胞受损 ,其损伤机制与凋亡有关 相似文献
78.
Weijian Zeng Xiaoxing Huang Weijie Luo Mingqian Chen 《The clinical respiratory journal》2022,16(8):562
IntroductionCommunity‐acquired pneumonia (CAP) is the major cause of infection‐related mortality worldwide. Patients with CAP frequently present with admission hyperglycemia.ObjectivesThe aim of this study was to evaluate the association between admission blood glucose (ABG) level and clinical outcomes in elderly CAP patients (≥80 years of age) with or without diabetes.MethodsIn this single center retrospective study, 290 elderly patients diagnosed with CAP were included. Demographic and clinical information were collected and compared. The associations between admission blood glucose level and the 30‐day mortality as well as intensive care unit (ICU) admission and invasive mechanical ventilation (IMV) in elderly CAP patients with or without diabetes were assessed.ResultsOf the 290 eligible patients with CAP, 159 (66.5%) patients were male, and 64 (22.1%) had a known history of diabetes at hospital admission. After adjusting for age and sex, the logistic regression analysis had identified several risk factors that might be associated with clinical outcomes in elderly patients with CAP. Multivariable logistic regression analysis revealed that admission glucose level > 11.1 mmol/L was significant associated with ICU admission, IMV, and 30‐day mortality both in non‐diabetic and diabetic patients. Furthermore, Kaplan–Meier analysis indicated that patients with higher admission glucose level were correlated statistically significantly with 30‐day mortality in patients with CAP (P < 0.001).ConclusionAdmission blood glucose is correlated with 30‐day hospital mortality, ICU admission, and IMV of CAP in elderly patients with and without diabetes. Specially, admission glucose > 11.1 mmol/L was a significant risk factor for 30‐day hospital mortality. 相似文献
79.
Yuehan Chen Xu Zhang Xiansheng Zeng Tingting Xu Wei Xiao Xuejiao Yang Wenzhi Zhan Chen Zhan Kefang Lai 《Journal of thoracic disease》2022,14(6):2079
BackgroundCough is one of the most common symptoms of coronavirus disease 2019 (COVID-19). However, the prevalence of persistent cough in recovered patients with COVID-19 during a longer follow-up remained unknown. This study aims to investigate the prevalence, and risk factors for postinfectious cough in COVID-19 patients after discharge.MethodsWe conducted a follow-up study for 129 discharged patients with laboratory-confirmed COVID-19 in two large hospitals located in Hubei Province, China from January 2020 to December 2020. Baseline demographics, comorbidities and smoking history were extracted from the medical record. Current symptoms and severity were recorded by a uniform questionnaire. Spirometry, diffuse function and chest computed tomography (CT) were performed on part of patients who were able to return to the outpatient department at follow-up.ResultsThe median (interquartile range) follow-up time was 8.1 (7.9–8.5) months after discharge. The mean (standard deviation) age was 51.5 (14.9) years and 57 (44.2%) were male. A total of 27 (20.9%) patients had postinfectious cough (>3 weeks), 6 patients (4.7%) had persistent cough by the end of follow-up, including 3 patients with previous chronic respiratory diseases or current smoking. Other symptoms included dyspnea (6, 4.7%), sputum (4, 3.1%), fatigue (4, 3.1%), and anorexia (4, 3.1%) by the end of follow-up. Thirty-six of 41 (87.8%) patients showed impaired lung function or diffuse function, and 39 of 50 (78.0%) patients showed abnormal CT imaging. Patients with postinfectious cough demonstrated more severe and more frequent cough during hospitalization (P<0.001), and more chronic respiratory diseases (P=0.01). In multivariate logistic regression analysis, digestive symptoms during hospitalization [odds ratio (OR) 2.95, 95% confidence interval (CI): 1.10–7.92] and current smoking (OR 6.95, 95% CI: 1.46–33.14) were significantly associated with postinfectious cough of COVID-19.ConclusionsA small part of patients developed postinfectious cough after recovery from COVID-19, few patients developed chronic cough in spite of a higher proportion of impaired lung function and abnormal lung CT image. Current smoking and digestive symptoms during hospitalization were risk factors for postinfectious cough in COVID-19. 相似文献
80.
背景 酒精使用障碍(AUD)是常见的慢性复发性精神疾病,对于重度AUD,需早期快速识别并及时妥善处理,以避免不可逆的伤害发生。目前,对AUD严重程度的评估主要基于临床医师对患者的精神检查,关于AUD严重程度影响因素及预测模型的研究有限。目的 分析AUD患者疾病严重程度的影响因素,构建风险预测模型,为评估AUD患者的疾病严重程度提供参考。方法 回顾性选取2017年1月1日—2022年12月31日南宁市第五人民医院收治的、符合《精神障碍诊断与统计手册(第5版)》(DSM-5)AUD诊断标准的1 358例首次住院患者为研究对象,收集其基本资料,根据疾病严重程度分为轻中度组(n=330)和重度组(n=1 028)。按7∶3将患者分为训练集和测试集,在训练集样本中构建Logistic回归模型,在测试集样本中采用受试者工作特征(ROC)曲线分析该模型对AUD严重程度的预测价值。结果 与轻中度组相比,重度组居住地在城市(χ2=7.804)、农民(χ2=17.991)、饮酒频率高于1~2次/天(χ2=35.267)的比例更高,初次饮酒年龄更大(t=-3.858),合并躯体疾病数量更多(Z=-22.782),γ-谷氨酰胺转移酶(χ2=259.940)和总胆红素异常(χ2=148.552)的比例更高(P均<0.01)。在训练集中进行的Logistic分析结果表明,农民(OR=2.024,95% CI:1.352~3.029)、初次饮酒年龄较大(OR=1.075,95% CI:1.025~1.129)、用餐时间外也饮酒(OR=3.988,95% CI:2.408~6.606)、总胆红素水平异常(OR=1.034,95% CI:1.000~1.069)、合并更多的躯体疾病(OR=4.386,95% CI:2.636~7.298)是AUD更严重的危险因素。该模型在测试集中的ROC曲线下面积(AUC)为0.906。结论 在精神专科医院中,农民、初次饮酒年龄较大、用餐时间外也饮酒、总胆红素水平异常、合并更多的躯体疾病可能是重度AUD的危险因素。 相似文献