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111.
112.
The influence of social factors, including social relationship, kinship, estrous cycle stage and hierarchical rank, on choice of a food source was studied in a group of 16 chimpanzees (Pan troglodytes) maintained in a large, outdoor compound. The subjects chose among three feeding stations that were spatially separated and located along the periphery of the compound. One feeding station was associated with a preferred food (orange), and two stations contained a less-preferred food (commercial chow or biscuit). A significant positive correlation was found between (a) the frequency with which one animal groomed another and the frequency with which they chose the same station during a given trial and (b) the percent of time that subjects were in close proximity and the frequency with which they chose the same station during a given trial, and this result was mediated by kinship. There was a significant difference in same-station choice by the adult male and by a maximally tumescent female compared to the choice when that female was detumescent. Finally, there was no significant correlation between social rank and the percent of trials during which the station associated with the more highly preferred food type was chosen. This study provided quantitative data supporting postulations that factors such as social relationship, kinship, and estrous cycle stage affect the composition of groupings of chimpanzees at feeding stations, and the results are consistent with field observations.  相似文献   
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社会认知是群居动物适应复杂环境和社会生活能力的体现,致力于理解自身、他人与社会。认知有利于促进利益分配的优化,而行为认知策略则是关注的热点问题。但迄今为止,川金丝猴如何进行社会地位与受孕状态等基础认知尚不清楚。本研究通过投食招引,在个体识别和等级判定的基础上,以栖息于秦岭观音山自然保护区熊猫谷景区的一个半野生川金丝猴群为对象,采用瞬时扫描和焦点动物取样法,观察并收集了猴群中6个一雄多雌单元成年雌雄个体的空间位置、邀配、交配及产仔行为数据,结合食物密度梯度"同心圆"和受孕周期,推测雌性成功受孕的交配时间段,运用配对t-检验统计证实受孕前后雌性的交配实现率差异显著(t=4.527,P=0.001),表现为受孕前雌性邀配行为获取的雄性响应率明显高于受孕后;通过Spearman相关性检验发现,雌性受孕前的交配实现率(R=0.527,P=0.006)及受孕时间(R=0.556,P=0.049)与自身等级均显著正相关,即高等级雌性邀配行为的雄性响应率及与雄性生殖性交配的时间明显高于或早于低等级雌性。结果表明,雄性川金丝猴拥有认知单元内成年雌性受孕状况和等级地位的能力,这种认知能力影响着雄性的性行为方式。  相似文献   
115.
Presumptive identification of different Enterobacteriaceae species is routinely achieved based on biochemical properties. Traditional practice includes manual comparison of each biochemical property of the unknown sample with known reference samples and inference of its identity based on the maximum similarity pattern with the known samples. This process is laborintensive, time-consuming, error-prone, and subjective. Therefore, automation of sorting and similarity in calculation would be advantageous. Here we present a MATLAB-based graphical user interface(GUI) tool named Bio Cluster. This tool was designed for automated clustering and identification of Enterobacteriaceae based on biochemical test results. In this tool, we used two types of algorithms, i.e., traditional hierarchical clustering(HC) and the Improved Hierarchical Clustering(IHC), a modified algorithm that was developed specifically for the clustering and identification of Enterobacteriaceae species. IHC takes into account the variability in result of 1–47 biochemical tests within this Enterobacteriaceae family. This tool also provides different options to optimize the clustering in a user-friendly way. Using computer-generated synthetic data and some real data, we have demonstrated that Bio Cluster has high accuracy in clustering and identifying enterobacterial species based on biochemical test data. This tool can be freely downloaded at http://microbialgen.du.ac.bd/biocluster/.  相似文献   
116.
基于AHP与Rough Set的农业节水技术综合评价   总被引:2,自引:0,他引:2  
由于不同区域自然条件的差异,农业节水技术自身特点及对应用环境条件的要求,导致不同农业节水技术的应用效果存在很大差异,有较大的不确定性,因此,如何筛选合理的评价指标,构建科学、全面的农业节水技术综合评价方法具有十分重要的意义。根据对农业节水技术应用效果的实地调研,应用Delphi法从调查获得的20项评价指标中筛选出了9项农业节水技术综合评价指标。其中节水率、积温和土壤肥力属于生态因子,产投比、劳动力投入和经济投入属于经济因子,可靠性、推广程度和农民认可度为社会因子。基于以上9项指标,构建了农业节水技术综合评价指标体系.综合评价方法(ARM)通过引入经验因子α对应用层次分析法(AHP)和粗糙集(Rough Set)所获得指标权重进行修订,使指标权重更加合理化。同时,分别应用AHP、Rough Set和ARM对甘肃省武威市的地膜覆盖、秸秆覆盖和常规畦田灌溉在大田中的应用效果进行了综合评价。评价结果显示,在对地膜覆盖技术评价中,AHP法过分强调了经济效益的作用(0.44),Rough Set法则强调的是生态效益(0.33)和社会效益(0.32),弱化了经济效益(0.05),ARM修正了以上2种方法的评价结果,获得地膜覆盖的经济效益、生态效益和社会效益,分别为0.36、0.20和0.13。在对秸秆覆盖评价中,与其它两种方法相比,Rough Set法的评价结果存在显著性差异,ARM修正获得的经济效益、生态效益和社会效益,分别为0.09、0.18和0.06。在对常规畦田灌溉评价中,Rough Set法强调了生态效益(0.28),经过修正获得的经济效益、生态效益和社会效益,分别为0.24、0.01和0.13。ARM的评价结果表明,采用地膜覆盖的经济效益最佳;同常规畦田灌溉相比较,地膜覆盖、秸秆覆盖的生态性指数分别比之高0.19和0.17,主要是由于秸秆覆盖具有保墒、增加土壤有机质以及在作物生长后期调节地温的作用,地膜覆盖具有节水、提高苗期土壤温度和促进提前出苗的作用;同秸秆覆盖相比,地膜覆盖和常规畦田灌溉的社会性指数分别高112.12%、18.18%,说明这两种技术在河西半干旱地区具有良好的社会基础。可见,在西北半干旱地区地膜覆盖用于种植玉米的效果最佳,而秸秆覆盖尽管其生态效益较高,但经济效益较低,推广应用存在一定的难度。  相似文献   
117.
Immune-endocrine interactions have been evaluated much less frequently in nonhuman primates, and this may be due, in part, to logistical and ethical concerns regarding trapping and sampling of endangered species, especially apes. Using noninvasive fecal collection methods, the present study evaluates possible relationships between fecal steroid levels and gastrointestinal parasite infections in the Ngogo chimpanzee community in Kibale National Park, Uganda. Because both testosterone and cortisol exhibit immunosuppressive effects in vitro and in other animal models, it was hypothesized that both testosterone and cortisol would be positively associated with gastrointestinal parasite infections in these animals. When placed in a mixed model simultaneously, both testosterone (F = 4.98, df = 1, P = 0.033) and cortisol (F = 5.94, df = 1, P = 0.020) were positively associated with total (helminth and protozoan) parasite richness (the number of unique intestinal parasite species recovered from hosts' fecal samples). It is possible that androgens and corticoids alter the ability of a host to mount an effective immune response against concomitant infection with multiple parasitic species. The utility of fecal samples for assessing immune-endocrine interactions is discussed.  相似文献   
118.
This article reports the structure of dominance and its relationship with social grooming in wild lion-tailed macaque females. The strength of dominance hierarchy was 0.79 on a scale of 0 to 1 indicating a moderate linearity in the ranking system. Dominance scores were converted into an ordinal as well as an interval scale. Grooming scores were also converted into interval scales using standard scores. Grooming received and grooming given correlated positively and negatively respectively with dominance ranks indicating that high ranking females received more and gave less grooming. Grooming was also positively related to encounter rates for dyads of females. More grooming among adjacent ranks, and grooming being more reciprocal, occurred only in the case of dominant females. The grooming patterns, therefore, appeared to be more of despotic than egalitarian nature. While ranking macaques into different Grades of social systems ranging from despotic to egalitarian, Thierry (2004) has placed lion-tailed macaques in Grade 3 corresponding to the ‘relaxed’ social system. Our results indicate that the grooming and dominance relationships in this species are more despotic, and hence, the Grade for this species requires to be shifted toward 2 or 1.  相似文献   
119.
关于瓦布贝母的分类等级研究   总被引:3,自引:0,他引:3  
基于营养体和花部形态,将瓦布贝母(F.wabuensis)降为暗紫贝母的一个变种:F.unibracteata var.wabuensis。  相似文献   
120.
C-peptide of insulin presents a promising new tool for behavioral ecologists that allows for regular, non-invasive assessment of energetic condition in wild animals. C-peptide is produced on an equimolar basis with insulin, thus is indicative of the body's response to available glucose and, with repeated measurement, provides a biomarker of energy balance. As yet, few studies have validated the efficacy of C-peptide for monitoring energy balance in wild animals. Here, we assess seasonal and interindividual variation in urinary C-peptide concentrations of East African chimpanzees (Pan troglodytes schweinfurthii). We assayed 519 urine samples from 13 adult male chimpanzees in the Kanyawara community of Kibale National Park, Uganda. C-peptide levels were significantly predicted by the total amount of fruit and the amount of preferred fruit in the diet. However, chimpanzees had very low C-peptide titers during an epidemic of severe respiratory illness, despite highly favorable feeding conditions. Kanyawara males had significantly lower C-peptide levels than males at Ngogo, a nearby chimpanzee community occupying a more productive habitat. Among Kanyawara males, low-ranking males had consistently higher C-peptide levels than dominant males. While counterintuitive, this result supports previous findings of costs associated with dominance in male chimpanzees. Our preliminary investigations demonstrate that C-peptide has wide applications in field research, providing an accessible tool for evaluating seasonal and individual variation in energetic condition, as well as the costs of processes such as immune function and reproduction.  相似文献   
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