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31.
微生物学实验作为生物学科的重要基础课程,在创新人才培养和素质教育中起着重要作用。提高学生的创新实践能力,培养服务区域经济的创新型应用人才是地方应用型本科高校的办学目标。结合长治学院的学科建设,探讨了普通地方本科院校应用型人才培养中,微生物学实验教学模式的新思路,建立了由基础性实验和综合设计性实验相结合的实验内容,开放学科实验室为学生搭建科研创新实践平台,借助微信平台实现"线上"与"线下"的互动交流学习,构建了科学考核评价体系。改革后的新型教学模式能够切实提高教学质量,对学生的能力培养和综合素质提升起到积极促进作用。  相似文献   
32.
The explanatory role of natural selection is one of the long-term debates in evolutionary biology. Nevertheless, the consensus has been slippery because conceptual confusions and the absence of a unified, formal causal model that integrates different explanatory scopes of natural selection. In this study we attempt to examine two questions: (i) What can the theory of natural selection explain? and (ii) Is there a causal or explanatory model that integrates all natural selection explananda? For the first question, we argue that five explananda have been assigned to the theory of natural selection and that four of them may be actually considered explananda of natural selection. For the second question, we claim that a probabilistic conception of causality and the statistical relevance concept of explanation are both good models for understanding the explanatory role of natural selection. We review the biological and philosophical disputes about the explanatory role of natural selection and formalize some explananda in probabilistic terms using classical results from population genetics. Most of these explananda have been discussed in philosophical terms but some of them have been mixed up and confused. We analyze and set the limits of these problems.  相似文献   
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34.
目的:分析新生儿ABO溶血病的临床相关危险因素,提高对新生儿ABO溶血病的防治水平。方法:选择ABO血型不合的孕妇433例,根据以上产妇产前IgG抗A(B)效价、产妇妊娠次数和产妇年龄分别分组,分析各组产妇间发生新生儿溶血病(HDN)的差异及临床相关性。结果:产妇产前IgG抗A(B)效价、产妇妊娠次数和产妇年龄均与HDN发生率呈正相关性(P<0.05);IgG抗A(B)效价>256时,HDN发生率将显著提高(P<0.01);产妇妊娠次数和年龄增加后,HDN发生率将显著增加(P<0.01)。结论:夫妻血型不合的产妇进行产前保健时,应进行IgG抗A(B)效价检查,当IgG抗A(B)效价>64或IgG抗A(B)效价进行性增加时,应及早做好HDN的干预措施;通过减少意外妊娠及高龄产妇数量,可减少HDN的发生。  相似文献   
35.
烟草工程专业微生物学课程教学初探   总被引:1,自引:0,他引:1  
烟草工程专业行业性明显,特色鲜明,微生物学是必修课程。为加强针对性,在当前没有专门教材的情况下,以现有教材为基础进行了适当取舍,只讲授必要的理论知识,实践教学着重规范实验操作,掌握基本技术,培养无菌意识。  相似文献   
36.
Simply observing other individuals interacting has been shown to affect subsequent behaviour and also hormones in 'bystander' individuals. However, immediate physiological responses of an observer have been hardly investigated. Here we present results on individuals' heart rate (HR) responses during various situations, which occur regularly in a flock of greylag geese (Anser anser, e.g. agonistic encounters, vehicles passing by). We recorded simultaneously HR and behaviour of 21 semi-tame free-roaming geese, equipped with fully implanted transmitters. We considered 304 social and 81 non-social events during which the focal individuals did not respond behaviourally. Independent of the spatial distance to the event, these HR responses were significantly greater in social contexts (e.g. departing or landing geese, agonistic interactions) than in non-social situations (e.g. vehicles passing by, thunder). Focal individuals showed a significantly higher maximum HR as well as a greater HR increase in response to agonistic interactions, in which the pair partner or a family member was involved, as compared with a non-affiliated goose. Also, HR was significantly higher when the bystander watched non-affiliated geese interacting, which were higher ranking than the focal. We conclude that these differences are due to different relevance of the recorded events for the focal individual, depending on the individuals involved in the observed interaction.  相似文献   
37.
Drug–drug interaction (DDI) defines a situation in which one drug affects the activity of another when both are administered together. DDI is a common cause of adverse drug reactions and sometimes also leads to improved therapeutic effects. Therefore, it is of great interest to discover novel DDIs according to their molecular properties and mechanisms in a robust and rigorous way. This paper attempts to predict effective DDIs using the following properties: (1) chemical interaction between drugs; (2) protein interactions between the targets of drugs; and (3) target enrichment of KEGG pathways. The data consisted of 7323 pairs of DDIs collected from the DrugBank and 36,615 pairs of drugs constructed by randomly combining two drugs. Each drug pair was represented by 465 features derived from the aforementioned three categories of properties. The random forest algorithm was adopted to train the prediction model. Some feature selection techniques, including minimum redundancy maximum relevance and incremental feature selection, were used to extract key features as the optimal input for the prediction model. The extracted key features may help to gain insights into the mechanisms of DDIs and provide some guidelines for the relevant clinical medication developments, and the prediction model can give new clues for identification of novel DDIs.  相似文献   
38.
模拟海平面上升对海滨木槿渗透调节的影响   总被引:1,自引:0,他引:1  
通过模拟海平面上升对海滨木槿主要渗透调节物质可溶性蛋白、可溶性糖和淀粉的影响发现,可溶性糖和可溶性蛋白均随水淹时间的延长呈现先升高后下降的变化,且变化较一致。而淀粉则呈先升高后下降再升高的N型曲线变化。另外通过对各个处理的分析比较发现,海滨木槿在海水淹浸35 cm·d-1和6 h·d-1环境下在渗透调节水平上仍然表现出较强的抗性。研究发现海滨木槿水淹胁迫程度较小的情况下可溶性糖与可溶性蛋白含量呈显著正相关,可溶性糖与淀粉呈显著负相关,说明海滨木槿在一定程度的水淹胁迫下主要渗透调节物质具有协同性,且水淹第21 d后存在可溶性糖向淀粉转化的可能。  相似文献   
39.
Vertebrates obtain social information about predation risk by eavesdropping on the alarm calls of sympatric species. In the Holarctic, birds in the family Paridae function as sentinel species; however, factors shaping eavesdroppers' reliance on their alarm calls are unknown. We compared three hypothesized drivers of eavesdropper reliance: (a) foraging ecology, (b) degree of sociality, and (c) call relevance (caller‐to‐eavesdropper body‐size difference). In a rigorous causal‐comparative design, we presented Tufted Titmouse (Baeolophus bicolor) alarm calls to 242 individuals of 31 ecologically diverse bird species in Florida forests and recorded presence/absence and type (diving for cover or freezing in place) of response. Playback response was near universal, as individuals responded to 87% of presentations (N = 211). As an exception to this trend, the sit‐and‐wait flycatcher Eastern Phoebe (Sayornis phoebe) represented 48% of the nonresponses. We tested 12 predictor variables representing measures relevant to the three hypothesized drivers, distance to playback speaker, and vulnerability at time of playback (eavesdropper's microhabitat when alarm call is detected). Using model‐averaged generalized linear models, we determined that foraging ecology best predicted playback response, with aerial foragers responding less often. Foraging ecology (distance from trunk) and microhabitat occupied during playback (distance to escape cover) best predicted escape behavior type. We encountered a sparsity of sit‐and‐wait flycatchers (3 spp.), yet their contrasting responses relative to other foraging behaviors clearly identified foraging ecology as a driver of species‐specific antipredator escape behavior. Our findings align well with known links between the exceptional visual acuity and other phenotypic traits of flycatchers that allow them to rely more heavily on personal rather than social information while foraging. Our results suggest that foraging ecology drives species‐specific antipredator behavior based on the availability and type of escape cover.  相似文献   
40.
生物学实践活动资源的开发与利用   总被引:1,自引:0,他引:1  
生物学实践活动资源是开展实践活动的重要基础,是培养学生生物科学素养的条件。在开发和利用生物学实践活动资源时,应当从三个方面入手。一是建设好学校生物园,开放生物实验室,充分挖掘校内实践活动资源的潜力;二是努力开发和利用校外实践活动资源,充分发挥动物园、植物园、学校周围的社区资源以及自然保护区、森林公园等自然生境的作用;三是有效开发和利用信息资源,发挥图书馆、教学软件和网络资源的作用。  相似文献   
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