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1.
Reciprocal immunization between parents of an Illinois family of ring-necked pheasants, Phasianus colchicus, resulted in antisera detecting two pairs of alloantigens segregating among 13 progeny. The four alloantigens were tentatively designated as 1 and 2, transmitted antithetically by the sire, and 3 and 4, transmitted antithetically by the dam. Genetic segregation occurring in second-generation progeny demonstrated that these two pairs of antigens belonged to a single genetic system. This alloantigen system was shown to correspond serologically to the major histocompatibility complex (MHC) of the chicken by cross-reactivity of the antigens of this system with specific subregional chicken MHC reagents, appropriately absorbed with erythrocytes of individual pheasants. These four haplotypes of the pheasant MHC were subsequently designated as MhcPhco-B1, MhcPhco-B2, MhcPhco-B3 and MhcPhco-B4. Traditional immunogenetic analysis of 30 pheasant families produced in this study disclosed a minimum of 14 pheasant haplotypes of this alloantigen system (MHC) to be segregating in the population under evaluation.  相似文献   
2.
Egg white proteins, hemoglobin, serum proteins and enzymes from Phasianus colchicus have been examined by starch gel electrophoresis. All three genetic parameters, mean proportion of loci polymorphic per population (P), mean numbers of alleles per locus (A), and mean proportion of loci heterozygous per individual (H), are given. Comparison were made between the proteins of the related species Coturnix coturnix japonica, and the variation of pheasant proteins is discussed in connexion with the genetic structure of the population studied.  相似文献   
3.
Population genetic theory and empirical evidence indicate that deleterious alleles can be purged in small populations. However, this viewpoint remains controversial. It is unclear whether natural selection is powerful enough to purge deleterious mutations when wild populations continue to decline. Pheasants are terrestrial birds facing a long-term risk of extinction as a result of anthropogenic perturbations and exploitation. Nevertheless, there are scant genomics resources available for conservation management and planning. Here, we analyzed comparative population genomic data for the three extant isolated populations of Brown eared pheasant (Crossoptilon mantchuricum) in China. We showed that C. mantchuricum has low genome-wide diversity and a contracting effective population size because of persistent declines over the past 100,000 years. We compared genome-wide variation in C. mantchuricum with that of its closely related sister species, the Blue eared pheasant (C. auritum) for which the conservation concern is low. There were detrimental genetic consequences across all C. mantchuricum genomes including extended runs of homozygous sequences, slow rates of linkage disequilibrium decay, excessive loss-of-function mutations, and loss of adaptive genetic diversity at the major histocompatibility complex region. To the best of our knowledge, this study is the first to perform a comprehensive conservation genomic analysis on this threatened pheasant species. Moreover, we demonstrated that natural selection may not suffice to purge deleterious mutations in wild populations undergoing long-term decline. The findings of this study could facilitate conservation planning for threatened species and help recover their population size.  相似文献   
4.
The foraging habitat selections of brown-eared pheasant (Crossoptilon mantchuricum) and the common pheasant (Phasianus colchicus) were studied in Huanglongshan Nature Reserve Shaanxi, China. Foraging habitat characteristics were measured on the basis of expected differences between species at 183 sites from November to December 2006 and January 2007. The results showed that both species selected foraging habitats with altitude (<1200 m), conifer forest, half sunny and half shady slope, sunny slope, density of trees (<5 individuals/100 m2), cover of shrub (>50%), visibility class (<10%) and distance to water source (<300 m). However, the brown-eared pheasant selected habitats with cover of trees (30–50%), middle or lower slope location, distance to edge of woods (<300 m) and human disturbance (<500 m), and the selection on density of shrub was not observed, compared to the selections on cover of trees (<30%), lower slope location, distance to edge of woods (<500 m) and human disturbance (<300 m), and density of shrub (>500 individuals/100 m2) for common pheasant. We also found that the common pheasant avoid predators by concealment whereas brown-eared pheasant evade predations by running away strategy.  相似文献   
5.
The foraging habitat selections of brown-eared pheasant (Crossoptilon mantchuricum) and the common pheasant (Phasianus colchicus) were studied in Huanglongshan Nature Reserve Shaanxi, China. Foraging habitat characteristics were measured on the basis of expected differences between species at 183 sites from November to December 2006 and January 2007. The results showed that both species selected foraging habitats with altitude (<1200 m), conifer forest, half sunny and half shady slope, sunny slope, density of trees (<5 individuals/100 m2), cover of shrub (>50%), visibility class (<10%) and distance to water source (<300 m). However, the brown-eared pheasant selected habitats with cover of trees (30–50%), middle or lower slope location, distance to edge of woods (<300 m) and human disturbance (<500 m), and the selection on density of shrub was not observed, compared to the selections on cover of trees (<30%), lower slope location, distance to edge of woods (<500 m) and human disturbance (<300 m), and density of shrub (>500 individuals/100 m2) for common pheasant. We also found that the common pheasant avoid predators by concealment whereas brown-eared pheasant evade predations by running away strategy.  相似文献   
6.
We isolated eight microsatellite loci from genomic DNA in Elliot's pheasant Syrmaticus ellioti using streptavidin‐coated magnetic beads. In the analyses of 53 individuals sampled, these loci displayed polymorphism varying from six to nine alleles per locus and observed heterozygosities ranging from 0.174 to 0.430. The results suggested that these novel microsatellite markers could become useful molecular tools for genetic studies of S. ellioti.  相似文献   
7.
暂时与群体分离的个体藏马鸡的反捕食警戒   总被引:3,自引:0,他引:3  
卢欣 《动物学报》2004,50(1):32-36
通过与同伴分担捕食风险 ,生活在稳定群体中的个体动物可以获得长期的适合度利益 ,但同时它们不得不承担食物竞争所带来的潜在代价。这种代价常常取决于食物资源的类型。当好的食物资源出现时 ,一些个体可以离开群体而独享这种资源。了解这些临时游离者如何组织其反捕食行为 ,在进化生态学上是有意义的。藏马鸡 (Crossoptilonharmani)是西藏雅鲁藏布江中游高山灌丛植被的一种典型的非繁殖季节集群鸟类。野外观察表明 ,为了独享好的食物资源 ,一些个体常常远离当前群体的活动范围。分离事件更可能发生于大的群体 ,但其发生率与参与者的数量呈负相关 ;而参与分离的个体愈多 ,分离持续的时间就愈长。分离者的个体警惕水平随着临时群体大小的增加而下降 ,遵从在其它自然大小鸟类群体所发现的一般性规律。分离行为的发生和持续时间被认为是个体对当前食物回报和捕食风险进行权衡的结果。这种利益 -代价权衡也可以解释藏马鸡所具有的强烈集群行为  相似文献   
8.
白腹锦鸡鸣声的声谱分析   总被引:8,自引:4,他引:4  
1986年1月—8月,12月及翌年1月,我们在云南省昆明市西部山区进行白腹锦鸡野外生态观察期间,录制了白腹锦鸡的鸣声。本文就啼叫声、呼唤声、惊叫声、恐惧叫声、威胁叫声及召唤雏鸟声等6种意义比较明确的鸣声进行了声谱分析,探讨各种鸣声与其相应的行为关系。  相似文献   
9.
10.
We examined hepatic cytochrome P450 activity in wild and hand-reared grey partridges (Perdix perdix), capercaillies (Tetrao urogallus) and ring-necked pheasants (Phasianus colchicus), as well as the enzyme activity in a variety of tissues of hand-reared Japanese quails (Coturnix coturnix japonica) and pigeons (Columba livia). Post-mortem decrease in hepatic enzyme activity in the grey partridge was measured. Hepatic 7-ethoxyresorufin-O-deethylase activity was similar in wild and hand-reared grey partridges and pheasants, but the activity was significantly lower in wild than in hand-reared capercaillies, probably resulting from their phenolic-rich diet. In the tissues of both quails and pigeons 7-ethoxycoumarin-O-deethylase exhibited the highest and 7-pentoxyresorufin-O-deethylase the lowest activity. Hepatic enzyme activity was significantly higher than that in other tissues. In the small intestine some activity could be found, reflecting some intestinal detoxication capacity. Enzyme activity decreased by 34-69% during the 30-min sampling period, which confirmed the importance of equalising sampling time to obtain comparable data. Because the hand-reared birds in this study were fed the same commercial diets, we assumed that the enzyme activity values detected reflect species differences without any induction by dietary secondary compounds.  相似文献   
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