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1.
The esophagus is a tubular-shaped muscular organ where swallowed fluids and muscular contractions constitute a highly dynamic environment. The turbulent, coordinated processes that occur through the oropharyngeal conduit can often compromise targeted administration of therapeutic drugs to a lesion, significantly reducing therapeutic efficacy. Here, magnetically guidable drug vehicles capable of strongly adhering to target sites using a bioengineered mussel adhesive protein (MAP) to achieve localized delivery of therapeutic drugs against the hydrodynamic physiological conditions are proposed. A suite of highly uniform microparticles embedded with iron oxide (IO) nanoparticles (MAP@IO MPs) is microfluidically fabricated using the genipin-mediated covalent cross-linking of bioengineered MAP. The MAP@IO MPs are successfully targeted to a specific region and prolongedly retained in the tubular-structured passageway. In particular, orally administered MAP@IO MPs are effectively captured in the esophagus in vivo in a magnetically guidable manner. Moreover, doxorubicin (DOX)-loaded MAP@IO MPs exhibit a sustainable DOX release profile, effective anticancer therapeutic activity, and excellent biocompatibility. Thus, the magnetically guidable locomotion and robust underwater adhesive properties of the proteinaceous soft microbots can provide an intelligent modular approach for targeted locoregional therapeutics delivery to a specific lesion site in dynamic fluid-associated tubular organs such as the esophagus.  相似文献   
2.
讨论了商业布草清洗消毒的现状,阐述了目前国内商业布草洗涤存在的问题及现在普遍使用的检测方法和标准,并分析了布草残留的主要原因,进一步探讨了商业布草洗涤领域热议的新发展、新技术。旨在让更多人了解到商业布草的现状,得到业内人士的关注,激发更多研究人员与管理人员改善商业布草洗涤消毒现存问题的欲望,进一步满足人们对高质量生活的要求。  相似文献   
3.
自然资源部在油气监管领域落实"放管服"改革,通过推行油气信息公示制度,使监管过程更加公开,油气矿业权人诚信自律程度加强,政府监管效能得以提高,但仍存在无法实现完全随机抽取检查人员、未完成法定最低勘查投入不足情况比较突出、内部管理信息共享不够等问题。油气监管面临诸多新形势和新要求,包括生态文明建设要求加强绿色勘查开采监管,油气上游放开带来监管主体更加多元,新实行的油气探采合一制度要求加强勘探开发过程监管,国家关于加强信用监管的要求。油气监管现状与新要求在监管制度、监管力量、监管成果使用、信息化支撑等方面还存在差距,为更好地适应新要求,持续加强油气勘查开采监督管理,提出完善油气监管制度体系顶层设计,加强油气探采合一制度下勘查开采过程和重要节点监管,培育油气监管专业机构并加大科技手段使用,推进信用监管和分类监管,构建联合监管和服务相结合的新模式等政策建议。  相似文献   
4.
Insulin is a peptide hormone with many physiological functions, besides its use in diabetes treatment. An important role of insulin is related to the wound healing process—however, insulin itself is too sensitive to the external environment requiring the protective of a nanocarrier. Polymer-based nanoparticles can protect, deliver, and retain the protein in the target area. This study aims to produce and characterize a topical treatment for wound healing consisting of insulin-loaded poly-DL-lactide/glycolide (PLGA) nanoparticles. Insulin-loaded nanoparticles present a mean size of approximately 500 nm and neutral surface charge. Spherical shaped nanoparticles are observed by scanning electron microscopy and confirmed by atomic force microscopy. SDS-PAGE and circular dichroism analysis demonstrated that insulin preserved its integrity and secondary structure after the encapsulation process. In vitro release studies suggested a controlled release profile. Safety of the formulation was confirmed using cell lines, and cell viability was concentration and time-dependent. Preliminary safety in vivo assays also revealed promising results.  相似文献   
5.
目的 研究美国FDA食品召回现状,为我国开展相应工作提供可借鉴的经验。方法 从FDA官方网站收集2019年食品召回信息,对数据进行筛选、整理,用EXCEL 2013进行数据分析。结果 从2019年FDA发布的每周执法报告中收集到的有效数据,共涉及461起召回事件和1 734种次召回食品。约60%的召回属于Ⅱ级,Ⅰ级大约占1/3,Ⅲ级最少。召回食品中,奶类最多,共310种次,占17.88%。召回原因中,微生物污染最多,占召回食品的37.89%、召回事件的31.45%。未标明过敏原导致的召回事件最多,占35.01%,但召回食品仅占18.40%。过程不当召回事件仅为3.47%,召回食品却高达24.63%。99%以上的事件和食品是企业自主召回,只有4起由FDA强制召回。结论 美国食品召回体系运行高效。FDA统一发布召回信息,方便公众查询和参与。过程不当召回事件少但召回量大,充分显示了生产过程监管的高效性。企业具有很强的安全责任意识,绝大多数召回由企业主动实施。我国的食品安全管理和召回工作,要进一步落实信息发布和交流,提高公众的参与度;努力转变终产品监管模式,发挥过程监管的作用;完善监督管理机制,努力提高企业的食品安全责任意识。  相似文献   
6.
英国区域绿色空间控制管理的发展与启示   总被引:1,自引:0,他引:1  
从国家到地方层面,对英国2011年以前区域绿色空间的实施控制方法进行了分析与总结。国家层面,通过制定系列的规划法令和规划指引政策体系,并结合部门导则性的文件,保护和调控区域绿色空间的区域整体发展;地方层面,通过地方发展框架编制过程中绿色基础设施(GI)规划的程序化引导,地区性的规划指引对国家层面政策指南的补充和细化,以及采用规划管理过程中的多元控制管理工具,保障区域绿色空间规划实施的控制管理。最后,通过分析我国近年来的相关规划与实施现状,讨论英国的这一体系对今后中国区域绿地规划管理发展的重要启示。  相似文献   
7.
Health information technology (IT) is a promising way to achieve safer medication management in the delivery of healthcare. However, human factors/ergonomics dictates that in order to make the complex, cognitive work of healthcare delivery safer, health IT must properly support human cognition. This means, for example, that new health IT must reduce, not increase, workload during safety-critical tasks. The present study was the first to quantitatively assess the short- and long-term impact of bar coded medication administration (BCMA) IT on nurses' mental workload as well as on perceived medication safety. One-hundred seventy registered nurses across 3 dissimilar clinical units at an academic, freestanding pediatric hospital in the Midwest US participated in surveys administered before, 3 months after, and 12 months after the hospital implemented BCMA. Nurses rated their external mental workload (interruptions, divided attention, being rushed) and internal mental workload (concentration, mental effort) during medication administration tasks as well as the likelihood of each of three medication safety events: medication administration errors, medication errors on the clinical unit, and clinical unit-level adverse drug events. Clinical unit differences were assessed. Findings generally confirmed the hypothesis that external but not internal mental workload was associated with the perceived likelihood of a medication safety event. Comparisons of mental workload from pre- to post-BCMA revealed statistically significant changes in the critical care unit only. Medication safety appeared to improve over the long term in the hematology/oncology unit only. In the critical care and medical/surgical units, medication safety exhibited short-term improvements that were eliminated over time. Changes in mental workload and medication safety, two classically microergonomic constructs, were deeply embedded in macroergonomic phenomena. These included the fit between the BCMA system and the nature of nursing work, the process of BCMA implementation, and BCMA interactions with concurrent changes occurring in the hospital. Findings raise questions about achieving sustainable performance improvement with health IT as well as the balance between micro- and macroergonomic approaches to studying technology change.Relevance to industryDesigners must consider how technology changes cognitive work, including mental workload. Hospitals and other implementers of technology must ensure that new technology fits its users, their tasks, and the context of use, which may entail tailoring implementation, for example, to specific clinical units. Evaluators must look over time to assess both changes in cognitive work and implementation issues. Healthcare practitioners must also recognize that new technology means a complex transformation to an already complex sociotechnical system, which calls for a macroergonomic approach to design and analysis.  相似文献   
8.
Internet surveys have become a very popular research tool. Relatively little attention has, however, been devoted to the possible changes in psychometric properties when measurements are obtained with Internet surveys. The Marlowe–Crowne Social Desirability Scale (MCSDS) is the most widely used instrument for measuring the tendency to respond in a socially desirable way and is often used to validate other measures. The purpose of the current research is to evaluate the dimensionality and reliability of measurements obtained with the MCSDS and short forms of the scale in an Internet sample of the general public in Iceland. An e-mail invitation was sent to a sample of 1200 panel members drawn from the Social Science Research Institute (SSRI) probability based panel, of those 536 participants completed all items on the MCSDS. Reliability estimates were in line with results from previous studies (α = .81 for the MCSDS data and α ranging from .59 to .75 for short forms). Using confirmatory factor analysis, a good fit was obtained for a one-factor model of measurements obtained with the MCSDS and its short forms (apart from significant chi square values in all cases but one), which generally supports the assumption of unidimensionality.  相似文献   
9.
Abstract : Orally administered anticancer drugs facilitate treatment, but the acidic conditions in the stomach often challenge their availability. PhenolaTi is a TiIV-based nontoxic anticancer drug with marked in-vivo efficacy. We report that nanoformulation protects phenolaTi from decomposition in stomach-like conditions. This is evidenced by similar NMR characteristics and similar in-vitro cytotoxicity toward murine (CT-26) and human (HT-29) colon cancer cells before and after incubation of nanoformulated phenolaTi (phenolaTi-F) at pH 2, unlike results with the unformulated form of the complex. Furthermore, administration of phenolaTi-F in animal drinking water revealed a notable inhibition of tumor growth in Balb/c and immune-deficient (Nude) mice inoculated with CT-26 and HT-29 cells, respectively. In-vivo efficacy was at least similar to that of the corresponding intraperitoneal treatment with phenolaTi-F and the clinically employed oral drug, capecitabine. No body weight loss or clinical signs of toxicity were evident in the phenolaTi-F-treated animals. These findings demonstrate a new convenient mode of cancer treatment through oral administration by safe titanium-based drugs.  相似文献   
10.
高校规模的不断扩大,教学改革的不断深化与有限教学资源的矛盾日益突出,现有的课程管理和服务无法满足学校快速发展的需求。流程重组通过分析和改进组织过程,可以更好地实现业务目标,该文将ESIA方法应用于业务流程再造,使用ESIA中的清除、简化、整合、自动化策略对排课流程中的问题进行优化,通过统一发布教学任务、集中排课、减少中间沟通环节等方法提升排课流程的效率和便捷性,极大地提高了师生的满意度、提升管理质量、为高校排课流程优化提供参考。  相似文献   
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