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目的:为了解决白芷生产过程中盲目引种、生产无序等导致的药材品质不达标、农残超标等问题,对白芷无公害规范化种植技术进行探讨。方法:利用药用植物全球产地生态适宜性区划信息系统(GMPGIS)Ⅱ对白芷栽培选地进行科学预测,得出潜在的白芷和川白芷各自生态适宜区。同时,根据白芷种质资源现状、产区考察、文献研究,建立一套无公害白芷规范化种植技术体系。结果:白芷引种栽培以黑龙江、河北、内蒙古、山西、河南一带为宜;川白芷引种栽培以湖南、江西、四川、浙江、贵州一带为宜。建立了一套从选地整地、播种、间苗定苗、施肥、田间管理、病虫害防治、采收储存、良种繁育的完整无公害白芷规范化种植体系。结论:白芷无公害规范化种植技术体系的建立为白芷无公害精细栽培奠定基础,也为现阶段中药材种植产业精细、集约、高产、高品质的种植发展方向提供参考。  相似文献   
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Activity spaces are increasingly used to understand how people interact with their environment and engage in activity but their use may raise challenges regarding causal inference. We conducted a systematic review of findings and the methodological, analytical and conceptual issues relevant to causal inference. Studies were included if they comprised a spatial summary of locations visited, assessed any part of the causal pathway between the environment, physical activity and health, and used quantitative or qualitative methods. We searched seven electronic databases in January 2018 and screened 11910 articles for eligibility. Forty-seven studies were included for review. Studies answered research questions about features of or environmental features within activity spaces using a range of spatial and temporal summary techniques. The conceptual challenge of using activity spaces to strengthen causal inference was rarely considered, although some studies discussed circularity, temporality, and plausibility. Future studies should use longitudinal and experimental designs and consider the potential and actual use of spaces for physical activity, and their relationship with total levels of activity.  相似文献   
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《Radiography》2020,26(1):e14-e17
IntroductionNewly-qualified radiographers often struggle with workplace integration. Frequently, their workplace environments stifle professional growth, leaving them frustrated and anxious. This results in poor workplace performance and possibly even attrition, hence the need to strategically structure their workplace environments for easier transition. In South Africa, no published studies exist detailing the workplace transition process for new radiographers, and the environmental requirements. This paper investigates the needs of this group, to provide information on how to create improved working environments which will encourage retention of newly-qualified radiographers.MethodsCriterion sampling was used to select five hospitals, and total sampling to select all newly-qualified radiographers at the selected hospitals. After obtaining ethical approval and participant consent, seven newly-graduated radiographers were interviewed utilising a phenomenological approach. One-on-one, face-to-face interviews were conducted, audio recorded, and transcribed verbatim. Interpretive phenomenological analysis was performed on the resultant dataset to identify themes.ResultsFour main themes emerged: interpersonal relations, support from fellow newly-qualified peers, departmental policies, and learning. Positive interpersonal relations were an essential component of the work environment; fellow newly-qualified radiographers at the same institution resulted in increased support; departmental policies needed to cater to the needs of new employees, and the environment must facilitate learning.ConclusionWhile a positive workplace environment is desirable for all radiographers, newly-qualified graduates have specific needs which require attention. Management has a crucial role to play in ensuring that such an environment is created to encourage new radiographer retention.  相似文献   
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Asthma and other inhaled allergies are some of the most common paediatric diseases. The association of exposure to allergens with induction and exacerbation of symptoms has been proven. The majority of allergens are permanently or periodically suspended in the air, which leads to impaired quality of life for sensitive patients. Therefore, many methods of prevention and therapy of allergic diseases have been developed. The method of allergen exposure avoidance is often the first and the most significant measure. The present research has been conducted to evaluate, based on scientific data, which measures have the most reliable evidence of effectiveness. Environmental allergen avoidance methods, despite limited evidence supporting their clinical efficacy, are listed as the main therapeutic approaches in most recommendations. The significance of the holistic approach is also emphasised: only simultaneous introduction of several avoidance methods can bring possibly beneficial effects for the patient.  相似文献   
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Environmental chemicals comprise a major portion of the human exposome, with some shown to impact the health of susceptible populations, including pregnant women and developing fetuses. The placenta and cord blood serve as important biological windows into the maternal and fetal environments. In this article we review how environmental chemicals (defined here to include man-made chemicals [e.g., flame retardants, pesticides/herbicides, per- and polyfluoroalkyl substances], toxins, metals, and other xenobiotic compounds) contribute to the prenatal exposome and highlight future directions to advance this research field. Our findings from a survey of recent literature indicate the need to better understand the breadth of environmental chemicals that reach the placenta and cord blood, as well as the linkages between prenatal exposures, mechanisms of toxicity, and subsequent health outcomes. Research efforts tailored towards addressing these needs will provide a more comprehensive understanding of how environmental chemicals impact maternal and fetal health.  相似文献   
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This study estimated the associations between neighbourhood characteristics and self-reported body mass index (BMI), waist circumference (WC), and waist-to-hip ratio (WHR) risk categories among Canadian men and women. Using data from the Alberta's Tomorrow Project (n = 14,550), we estimated 3- and 4-way intersections, business destinations, population count, and normalized difference vegetation index (NDVI) within a 400 m radius of participant's home. Intersections, business destinations, and population count (z-scores) were summed to create a walkability score. Four-way intersections and walkability were negatively associated with overweight and obesity. Walkability was negatively associated with obesity. NDVI was negatively associated with high-risk WHR and population count and walkability positively associated with high-risk WHR. Among men, population count and walkability were negatively associated with obesity, and business destinations and walkability were negatively associated with overweight and obesity. Among women, NDVI was negatively associated with overweight (including obesity), obesity, and high-risk WC. Interventions promoting healthy weight could incorporate strategies that take into consideration local built environment characteristics.  相似文献   
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目的 基于AERMOD模型机理,研究其在核设施辐射环境影响评价中的应用。方法 根据给定的释放源项和厂址气象数据,模拟获取核设施常规运行时气态放射性核素浓度分布,并进一步定性分析气态流出物浓度峰值落地点和时间分布,研究AERMOD模型在核设施辐射环境影响评价中的适用性和应用前景。结果 通过AERMOD模型适用性和应用前景分析,得出该模型总体满足核设施气态流出物浓度分布计算需求,可应用于核设施气态流出物扩散趋势和敏感点分析,并可为核设施常规运行的监测计划提供数据支撑。结论 本研究可为今后深入开展AERMOD模型在核设施辐射环境影响评价中的应用提供参考。  相似文献   
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To deal with the Covid 19 pandemic, health protection measures require changes to our clinical practices. Faced up with the unprecedented nature of this situation, the liberal psychotherapist is led to rethink some aspects of the framework of his practice in order to preserve the thread of the transferential relationship. The authors develop a clinical reflection on the clinical setting in a pandemic period by exploring in particular the dynamics of telephone sessions. For telephone interviews, the question of the sound envelope is central, in particular regarding the psychic function of silence. We choose to illustrate our point with short vignettes than by relying on long-term clinical cases, more likely to represent the variety of new clinical situations encountered and the questions that accompany them. This article introduces his point by recounting the plague epidemic in ancient Greece to show the impact of the environment on humans and its collective fantasy implications. Being faced up with death, contamination, the invisible enemy brings out a palpable concern. It is indeed quite remarkable that these same reactions and concerns in front of death caused by the pandemic match whith what is related by Thucydides who survived the plague, which affected Athens during the Peloponnesian War. In another context, Winnicott highlights the place and importance of the therapeutic environment. It is both a question of adjusting the framework according to the context while maintaining certain intangible aspects representing the permanence of the link and its framework. A framework cannot exist without being kept, which is equivalent to thinking of the framework above all as an internal framework, questioning the clinician about what he values and what he makes sense in his practice. In the current context, these questions arise from the perspective of a certain flexibility, depending on the human context (child, adolescent, consultations, etc.) or external context (crisis linked to a virus, etc.) showing that it is more than never question of exercising on a case-by-case basis, taking into account changes in the environment. The initial observation during this period of confinement concerns the fact that some patients contact a therapist for the first time by telephone and wish to initiate psychotherapy (during this period) when they explain that such an initiative was not possible. despite the difficulties already encountered in the past. But there is also the opposite case: patients who have no intention of continuing the work already started during this time. Thus, faced up with the injunction of confinement, they show themselves in the psychic impossibility of following the treatment by other means such as, for example, telephone sessions. In this perspective, the silence on the phone takes on a different tone; silence reveals itself to be a source of greater anxiety than in presence: the presence of bodies, of its movements perceptible as imperceptible, of a gesture that carries or accompanies the senses, breathing, the visual context of the office and of its “decor”, represent as many essential elements in the usual capacity of the frame; in the absence of these basic sensory elements, silence can be experienced as a void, or even a gap in the bond, opening Pandora's box of paranoid fantasies acting unconsciously. If silence is representative of the whole framework, it promotes in this context the partialization of the clinician's body reduced to one ear and not to a whole body. Here, it is the change of framework that mobilizes the difference, established by Mr. Klein, between the partial and total object; this circumstance neo-framework could therefore call for regressive movements, undoing the silence of its symbolic function when the bodies are present.  相似文献   
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