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Objective: To investigate the effect of Potentilla fulgens extract on lipid peroxidation and antioxidant status in male mice as a function of age.

Methods: Eighteen-month-old Swiss albino male mice were administered the dichloromethane-methanol extract of P. fulgens (250?mg/kg b.w.) on alternate days via intraperitoneal route for a period of 14 days. Lipid peroxidation and activities of catalase (CAT) and glutathione peroxidase (GPx1) in liver and kidney were measured and serum oxygen radical absorbance capacity (ORAC) assay was estimated. Phytochemical analysis of P. fulgens extract using high performance thin layer chromatography (HPTLC) was carried out with gallic acid, quercetin, catechin, and epicatechin as markers.

Results: Significant increase in level of thiobarbituric acid-reactive substances (TBARS), decreased GPx1, and CAT activities as well as reduction in ORAC were observed in 18-month-old mice as compared to that of 2-month-old mice. Treatment with P. fulgens extract significantly lowered TBARS level, ameliorated CAT, and GPx1 activities in liver and kidney and improved serum ORAC in aging mice. HPTLC studies revealed well resolved bands of P. fulgens extract containing epicatechin and catechin.

Discussion: This study showed that P. fulgens is a potent antioxidative agent, which can emerge as a promising candidate in alleviating the age-associated oxidative stress and related diseases.  相似文献   
3.
Red panda Ailurus fulgens, an endangered habitat specialist, inhabits a narrow distribution range in bamboo abundance forests along mountain slopes in the Himalaya and Hengduan Mountains. However, their habitat use may be different in places with different longitudinal environmental gradients, climatic regimes, and microclimate. This study aimed to determine the habitat variables affecting red panda distribution across different longitudinal gradients through a multivariate analysis. We studied habitat selection patterns along the longitudinal gradient in Nepal's Himalaya which is grouped into the eastern, central, and western complexes. We collected data on red panda presence and habitat variables (e.g., tree richness, canopy cover, bamboo abundance, water availability, tree diameter, tree height) by surveys along transects throughout the species’ potential range. We used a multimodal inference approach with a generalized linear model to test the relative importance of environmental variables. Although the study showed that bamboo abundance had a major influence, habitat selection was different across longitudinal zones. Both canopy cover and species richness were unimportant in eastern Nepal, but their influence increased progressively toward the west. Conversely, tree height showed a decreasing influence on habitat selection from Eastern to Western Nepal. Red panda's habitat selection revealed in this study corresponds to the uneven distribution of vegetation assemblages and the dry climatic gradient along the eastern‐western Himalayas which could be related to a need to conserve energy and thermoregulate. This study has further highlighted the need of importance of bamboo conservation and site‐specific conservation planning to ensure long‐term red panda conservation.  相似文献   
4.
由于标记缺失、生产记录不详、亲权关系不明及部分个体来源不清等历史问题,中国小熊猫圈养种群存在谱系错漏、近亲繁殖等风险。近年来,随着小熊猫种群规模不断扩大,管理者们对谱系的准确性提出了更高的需求,亲子鉴定工作也成为了研究的重点。本文采用26个微卫星标记,对国内3个小熊猫圈养种群进行了亲缘关系运算,完成了相关谱系的查错与整理。26个位点多态性与稳定性良好,联合非亲排除概率达到0.9999以上,可解决国内小熊猫圈养种群的各类亲子鉴定需求。在单亲未知或双亲未知的情况下,8或11个位点组合可实现亲子鉴定。5个位点组合可进行个体识别。在小熊猫圈养管理过程中,应用一套亲子鉴定体系对小熊猫圈养的谱系进行查漏补缺,有利于制定科学的配对计划、避免近亲繁殖,对小熊猫种群保护有着重要意义。  相似文献   
5.
圈养小熊猫繁殖行为变化及繁殖行为对策   总被引:6,自引:1,他引:6  
In order to investigate the change of reproductive behaviors and understand reproductive strategies of both male and female red pandas, one-year behavioral observation was conducted through the focal sampling method in the Chengdu Research Base of Giant Panda Breeding from December 1999 to November 2000. Our results indicated that reproductive behaviors showed significant differences between the estrous and non-estrous seasons. Frequencies of the rubbing anogenital, sniffing and licking marking were much higher in estrus than in non-estrus. Bleating only appeared in the estrus and can be regarded as an estrous indicator.The result also demonstrated that both male and females applied different reproductive behavioral strategies. Frequencies of activity, rubbing anogenital, licking and sniffing marking, and bleat were much higher in the male than in the female. However, those of resting and investigating were much lower in the male than in the female. This indicated that the male was more active than the female during the estrus and might imply that the male acts mainly as an estrous message sender, and the female as a message receiver in the estrous season.  相似文献   
6.
大熊猫和小熊猫粪便DNA提取的简易方法   总被引:29,自引:0,他引:29  
采集了大熊猫和小熊猫的新鲜粪便样品 ,使用 1 0 0 %乙醇保存。通过重复离心富集研究动物的肠道脱落细胞 ,并使用乙醇和双蒸水洗涤以除去抑制物。用 1 %的SDS快速裂解细胞 ,离心除去残渣后 ,向裂解液中加入蛋白酶进行消化。消化结束后使用等体积的酚 /氯仿抽提 ,乙醇沉淀DNA。用双蒸水溶解粪便DNA后 ,使用PCR产物纯化试剂盒对粪便DNA进行纯化。电泳检测结果显示 ,从乙醇保存的大、小熊猫粪便样品中抽提到高质量的粪便DNA。对线粒体控制区、细胞色素b基因、 1 2SrRNA基因的PCR扩增反应以及测序结果也证实了样品保存方法和DNA抽提方法可靠而高效。此方法使用实验室内常用的分子生物学试剂 ,不仅克服了分子粪便学研究中常见的抑制物粪便DNA微量降解严重等障碍 ,与商业化的粪便抽提试剂盒 (QIAampDNAStoolMiniKit,Qiagen)相比还是一种经济的试验方法 (抽提反应成本为试剂盒的 1 / 5 )。文中还对粪便DNA内细菌基因组等背景DNA可能对分子粪便学试验结果的影响进行了探讨。在基于PCR技术的遗传学研究中 ,对于植食性动物而言 ,粪便内的背景DNA对目标动物DNA片断的扩增和序列测定未见影响 ;但对于肉食性动物 ,则必须考虑被捕食者基因组对试验可能产生的影响 ,应谨慎对待  相似文献   
7.
A total of 15 polymorphic tetranucleotide microsatellite loci in the red panda, Ailurus fulgens, were characterized in this study. Based on evaluations of 33 red pandas, the number of observed alleles for each locus ranged from seven to 17 and the expected and observed heterozygosities were 0.412–0.897 and 0.121–0.909, respectively. The mean polymorphic information content was 0.721. These markers would greatly strengthen the utilization of microsatellite tools in genetic variation studies in red panda populations.  相似文献   
8.
Aerodynamic theory predicts that migrant fliers should reduce their speed of flight as endogenous energy reserves are gradually consumed. This prediction was tested for Urania fulgens (Walker) moths migrating through central Panama in 1987 and again in 1998. Direct airspeed measurements together with chloroform:methanol extractions of abdominal lipids were used to determine that, contrary to theoretical predictions, the speed of flight among individuals was independent of both body mass and abdominal lipid mass.  相似文献   
9.
We report on the isolation and characterization of 10 microsatellites in the red panda Ailurus fulgens from genomic DNA‐enriched libraries. Twenty‐one microsatellites were screened from the libraries, and 10 of the screened microsatellites were polymorphic. The number of observed alleles for each locus in 24 individuals ranged from three to 12, and the expected and observed heterozygosity was 0.60–0.90 and 0.50–1.00, respectively. These markers should prove a useful tool for the study of genetic variation in red panda in the future.  相似文献   
10.
The reproduction of female red pandas under three different husbandry conditions (monogamy, polygamy, and polyandry) was studied at the Chengdu Research Base for Giant Panda Breeding, and Chengdu Zoological Park, China. We monitored the fecal steroid profiles of seven females by radioimmunoassay in order to understand how the different mating groupings affect the animals' reproductive success. Of the seven females studied, all gave birth except the one that was kept in the polyandrous group. Although fecal estradiol metabolites exhibited several peaks during estrus, only one coincided with mating behavior. Fecal progesterone metabolites did not display a sustained rise in the absence of mating behavior, even though estradiol displayed a peak of secretion. This suggests that the red panda may be an induced ovulator. During gestation, fecal progesterone metabolites were maintained at a comparatively high level, and were much higher than those of nonpregnant females. The female in the polyandrous group showed an abnormal estradiol metabolite profile, with a level that was four to five times higher than those of the females in the polygynous groupings. It was observed that this female always escaped and hid in the trees to avoid courtships with males, and did not give birth. This phenomenon suggests that polyandrous groupings may be unsuitable for successful reproduction in captivity. Zoo Biol 24:169–176, 2005. © 2005 Wiley‐Liss, Inc.  相似文献   
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