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1.
目的:探索从马棘种子中提取羽扇豆醇的最佳工艺以及液相色谱法-质谱法联用(LC-MS)与气相色谱法-质谱法联用(GC-MS)峰面积关联度。方法:1)采用L9(34)正交试验优选马棘提取羽扇豆醇最佳工艺,GC-MS检测峰面积;2)根据LC-MS检测单因素实验含量,3种溶剂(95%乙醇、乙酸乙酯、石油醚)分别在10倍液料比下浸提5 d、15 d,与正交实验相同工艺下峰面积进行比值,并推导正交实验羽扇豆醇含量。结果:1)正交实验26条工艺路线所获样本经GC-MS检测后换算含量及中位数检验,其中位数值为4 503.655 μg;羽扇豆醇含量最高为石油醚、浸提5 d、10倍液料比;95%乙醇、浸提5 d、5倍液料比含量最低;排除石油醚后,95%乙醇、浸提5 d、10倍液料比含量最高;2)相同工艺下的样品,GC-MS值经含量推导,差异无统计学意义(P>0.05),且95%乙醇、乙酸乙酯、石油醚对应比值分别为315.91、208.25、1 305.83。结论:1)从安全、经济及工业化生产角度,马棘种子采用95%乙醇、浸提15 d、10倍液料比方法提取较好;2)GC-MS常定性某成分的有无,不作为定量依据,一次检测可获得多种物质的信息;LC-MS一般作定量依据,但1次只能检测1个成分的含量。从本实验看,GC-MS的峰面积值似可以与LC-MS进行大体含量推导。这为初步判断GC-MS峰面积值提供了一个便捷方法,值得进一步积累数据,找出规律。  相似文献   
2.
【目的】 探讨医学期刊编辑处理生物医学研究伦理问题的方式,为推动确立医学期刊伦理审查规范提供参考。【方法】 通过问卷星向国内医学期刊编辑发放调查问卷,对审稿时和论文出版后处理医学伦理相关问题的方式展开调研。【结果】 共回收问卷230份。调查显示:在审稿阶段,在保护患者隐私方面,英文期刊、中英双语期刊的编辑更注重要求作者提供授权同意相关证明材料;中、英文期刊以及中英双语期刊的编辑对涉及人体试验伦理问题的处理方式都比较规范。但是,对于研究是否获得患者知情同意、动物实验研究是否经过伦理委员会审查、回顾性研究是否需要伦理审查、涉及人的研究是否在临床试验注册中心注册等问题,编辑还需要进一步重视。在论文出版后,编辑发现的医学伦理问题主要是“涉及人的研究未说明是否经过伦理委员会审查”。对论文出版后发现的没有保护患者隐私和没有在临床试验注册中心注册的问题,大部分期刊缺乏相关处理方案。【结论】 编辑应加强对论文知情同意、动物实验伦理、回顾性研究伦理的审查,并审查涉及人的研究是否在临床试验注册中心注册,以推动我国医学期刊的高质量发展。  相似文献   
3.
《Value in health》2022,25(8):1290-1297
ObjectivesThe COVID-19 pandemic forms an unprecedented public health, economic, and social crisis. Uptake of vaccination is critical for controlling the pandemic. Nevertheless, vaccination hesitancy is considerable, requiring policies to promote uptake. We investigate Dutch citizens’ preferences for policies that aim to promote vaccination through facilitating choice of vaccination, profiling it as the norm, making vaccination more attractive through rewards, or punishing people who reject vaccination.MethodsWe conducted a discrete choice experiment in which 747 respondents were asked to choose between policies to promote vaccination uptake and their impacts on the number of deaths, people with permanent health problems, households with income loss, and a tax increase.ResultsRespondents generally had a negative preference for policies that promote vaccination. They particularly disliked policies that punish those who reject the vaccine and were more favorable toward policies that reward vaccination, such as awarding additional rights to vaccinated individuals through vaccination passports. Respondents who reject vaccination were in general much more negative about the policy options than respondents who consider accepting the vaccine. Nevertheless, vaccination passports are supported by both respondents who accept the vaccine, those who reject vaccination, and those who are unsure about vaccination.ConclusionsThis study provides concrete directions for governments attempting to increase the vaccination uptake in ways that are supported by the public. Our results could encourage policy makers to focus on policy options that make vaccination easier and reward people who take the vaccine, as especially the implementation of vaccination passports was supported.  相似文献   
4.
目的 探讨基于正交试验的肾造瘘管不同固定方案的比较效果。方法 将14Fr硅胶肾造瘘管固定在聚乙烯展板和拉力显示器上,以固定材料、固定方法、面积为3个影响因素,每个因素3个水平,每组进行3次试验再求平均值作为最后拉力值F,共进行9个固定方案共27次试验。利用L9(33)正交试验矩阵研究不同材料(医用橡皮膏、医用透气胶带、医用无纺布胶带)、固定方法(交叉固定法、“工”字固定法和改良“工”字固定法)及面积(16 cm2、24 cm2、32 cm2)对肾造瘘管固定强度的影响。结果 正交试验所选的3种影响因素中,对拉力值影响显著性排序为:材料>方法>面积;3种固定材料中,医用橡皮膏固定强度最大。结论 肾造瘘管固定方案中,最佳固定组合为以医用橡皮膏结合改良“工”字法固定,可为临床管道固定方案的选择提供参考。  相似文献   
5.
目的制备盐酸益母草碱片,并进行质量评价。方法采用湿法制粒技术,以盐酸益母草碱为原料药,采用单因素实验筛选填充剂、崩解剂、黏合剂、润滑剂种类;结合正交实验,以15 min累积溶出度(以水为溶出介质)为指标,筛选崩解剂占比、黏合剂溶液质量分数、润滑剂占比,并进行验证。按2020年版《中国药典》(四部)通则方法对所制盐酸益母草碱片的体外溶出行为(溶出介质分别为pH1.2的盐酸溶液、pH4.5的醋酸-醋酸钠溶液、pH6.8的磷酸盐缓冲液、水)、片剂外观、硬度、脆碎度、含量均匀度进行检测。结果盐酸益母草碱片的最优处方为盐酸益母草碱原料药500 mg、糊精9250 mg、交联聚维酮200 mg、硬脂酸镁50 mg、1%羟丙甲纤维素溶液4 mL。所制3批片剂的平均15 min累积溶出度为81.25%(RSD=1.12%,n=3)。在上述4种溶出介质中,所制片剂均能在30 min内达到溶出平衡,且累积溶出度均超过85%。所制片剂外观颜色均一,呈米黄色,表面光滑,边缘完整,无杂色、斑点、异物等,硬度为57.3 N(n=6),减重率为0.15%,含量均匀度符合2020年版《中国药典》(四部)相关规定。结论成功制备了盐酸益母草碱片,且质量符合相关规定。  相似文献   
6.
《Value in health》2022,25(8):1404-1415
ObjectivesThis article determines public stated preferences around different factors that influence the choice to make clinical negligence claims against a national healthcare system.MethodsA large online survey was conducted using a discrete choice experiment (DCE) with the UK general population (N = 1013). DCE tasks involved a single profile and participants chose whether to make a claim for compensation (yes/no) after one of 3 randomly allocated patient safety incident (PSI) “scenarios” of different severities (mild, moderate, severe). DCE attributes described the actions of the healthcare system after a PSI and characteristics of the clinical negligence claims process. The data were modeled separately for each scenario (mild, moderate, severe) using logistic regression. Marginal effects and the probability of making a claim in a baseline case were estimated.ResultsProbability of choosing to claim was reduced by receipt of an apology, investigation and prevention of recurrence of the PSI, and longer time until claim decision and increased by an easy and straightforward claims process and high chance of compensation and for the mild scenario higher compensation amounts. Marginal effects and baseline case probabilities differed by scenario severity.ConclusionsThe results suggest the actions of the healthcare system after a PSI and characteristics of the claims process have a larger impact on the probability of making a claim for milder PSIs. For more severe PSIs, a larger probability of making a claim was observed, and the choice was less influenced by the actions of the healthcare system after the PSI and characteristics of the claims process.  相似文献   
7.
目的 建立厚朴麻黄汤物质基准质量标准,并优化其制剂提取工艺。方法 制备15批厚朴麻黄汤物质基准对应实物并检测出膏率。采用高效液相色谱法检测指标性成分(厚朴酚、和厚朴酚、盐酸麻黄碱及盐酸伪麻黄碱)含量与特征图谱,分析指标性成分从饮片到对应实物的转移率,评价特征图谱的相似度。以出膏率、指标性成分转移率为指标,采用L9(34)正交试验优化厚朴麻黄汤的制剂提取工艺(液料比、提取时间、提取次数)。结果 15批对应实物的出膏率为11.10%~13.13%,指标性成分质量分数及饮片-对应实物转移率分别为厚朴酚0.034%~0.051%、1.474%~2.801%,和厚朴酚0.030%~0.059%、2.154%~4.241%,盐酸麻黄碱0.309%~0.377%、23.278%~37.774%,盐酸伪麻黄碱0.138%~0.233%、27.417%~47.658%。各批次特征图谱与对照图谱间的相似度均大于0.9。综合考虑出膏率、成分转移率及生产实际,确定最优工艺为提取3次,分别加8、6、6倍量水,分别提取1.0、1.0、0.5 h。结论 结合出膏率、指标性成分含量及特征图谱对厚朴麻黄汤的物质基准质量属性进行全面分析,并优化其制剂提取工艺,可为厚朴麻黄汤质量标准的建立及后续开发提供参考。  相似文献   
8.
《Value in health》2022,25(5):835-843
ObjectivesThe EuroQol Group published the EQ-5D-Y valuation protocol that recommends 2 valuation techniques to elicit preferences: composite time trade-off (C-TTO) and discrete choice experiments (DCEs). The protocol left the decision of what modeling approach to use open for researchers. Our aims were to explore modeling strategies allowing generation of EQ-5D-Y value sets and to produce an EQ-5D-Y Spanish value set.MethodsWe used EQ-5D-Y DCE and C-TTO data collected in Spain following the protocol and adopted a staged approach for our modeling exercise. First, we selected the best performing DCE latent class model and evaluated models from 2 to 10 classes. We selected the preferred model based on best goodness of fit in terms of the Bayesian information criterion. We considered 2 anchoring approaches to estimate utility values: (1) pits state anchoring and (2) hybrid models (using all available C-TTO responses). All analysis were weighted to be representative of the Spanish population.ResultsWe collected 1005 DCE and 200 C-TTO interviews. We selected a DCE model including 4 classes. Hybrid models using all available C-TTO observations produced a narrower range of values than the pits state anchoring approach.ConclusionsIn this article, we have presented an EQ-5D-Y value set that can be used for cost-utility analysis in Spain. The international EQ-5D-Y valuation protocol should be updated to include a different set of health states for the C-TTO experiment if researchers wish to use alternative anchoring approaches to the “pits state.”  相似文献   
9.
The EORTC QLU‐C10D is a new multi‐attribute utility instrument derived from the widely used cancer‐specific quality of life questionnaire, EORTC QLQ‐C30. It contains 10 dimensions (physical functioning, role functioning, social functioning, emotional functioning, pain, fatigue, sleep, appetite, nausea, bowel problems), each with four levels. The aim of this study was to provide U.K. general population utility weights for the QLU‐C10D. A U.K. online panel was quota‐sampled to align the sample to the general population proportions of sex and age (≥18 years). The online valuation survey included a discrete choice experiment (DCE). Each participant was asked to complete 16 choice‐pairs, each comprising two QLU‐C10D health states plus duration. DCE data were analysed using conditional logistic regression to generate utility weights. Data from 2,187 respondents who completed at least one choice set were included in the DCE analysis. The final U.K. QLU‐C10D utility weights comprised decrements for each level of each health dimension. For nine of the 10 dimensions (all except appetite), the expected monotonic pattern was observed across levels: Utility decreased as severity increased. For the final model, consistent monotonicity was achieved by merging inconsistent adjacent levels for appetite. The largest utility decrements were associated with physical functioning and pain. The worst possible health state (the worst level of each dimension) is ?0.083, which is considered slightly worse than being dead. The U.K.‐specific utility weights will enable cost–utility analysis (CUA) for the economic evaluation of new oncology therapies and technologies in the United Kingdom, where CUA is commonly used to inform resource allocation.  相似文献   
10.
[目的] 优选复方夏枯草洗剂的提取工艺。[方法] 采用L9(34)正交设计,以迷迭香酸、丹酚酸B的含量及出膏率的综合评分为指标,考察料液比、提取时间、提取次数对提取效果的影响,优选复方夏枯草洗剂的最佳提取工艺。[结果] 根据综合评分的结果,优选出最佳提取工艺为加8倍水,提取3次,每次0.5 h。[结论] 该工艺准确可靠,可行性好。  相似文献   
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