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1.
25种脊椎动物不同组织乳酸脱氢酶同工酶谱比较   总被引:2,自引:0,他引:2  
用pH 8.9不连续系统聚丙烯酰胺凝胶电泳方法,结合尿素抑制和热稳定性实验,对25种脊椎动物不同组织中LDH同工酶的分布和性质进行了比较分析。实验结果,草鱼、鲫鱼、带鱼和(鱼免)鱼不同组织中除了有A、B亚基组合而成的LDH同工酶分布外,在草鱼肝、肾脏中检出向阳极慢速迁移的F_4同工酶带。同时在带鱼眼球中检出向阳极快速迁移的E_4同工酶带。海洋底栖的木叶鲽几种组织以A_4同工酶形式存在。从两栖到哺乳动物,除了具有特殊电泳行为的无斑雨蛙、乌龟、鳖、鸡和乌鸦外,其它动物不同组织中存在着由A、B亚基以四聚体组合而成五种LDH同工酶分布的酶带;在哺乳动物睾丸组织中检出C_4同工酶,褐家鼠和雪兔的C_4同工酶分布在LDH_4和LDH_5之间,而刺猬的C_4酶带分布在LDH_5之后,是慢速向阳极迁移的酶带。比较分析了脊椎动物中不同纲的种类LDH同工酶分布特征。认为LDH同工酶谱的变化与脊椎动物系统发生之间不存在平行关系。  相似文献   
2.
陈辉  刘鹏  赵文阁  周志龙 《野生动物》2009,30(6):306-309
2002~2009年,对黑龙江省海林市横道河子镇威虎山影视基地夏季脊椎动物物种多样性进行调查,结果表明:该地区夏季常见脊椎动物有122种,其中圆口纲动物1种、鱼类11种、两栖类6种、爬行类5种、鸟类83种、哺乳类16种,每年平均能够见到79种,由于道路施工以及影视剧拍摄等人为活动干扰使得该地区脊椎动物的物种多样性从2005年显著减少,现正逐步恢复。  相似文献   
3.
A comprehensive literature review was conducted to identify the magnitude of bird and rodent damage to 19 economically important crops in California. Interviews with agriculture experts provided additional information about damages. Monte Carlo simulations were used to derive summary estimates of damages to each crop. A meta-analysis indicated that summary damage estimates from expert interviews were higher than estimates from field studies and surveys. It was also found that there has been a downward trend over time in damages to almonds and grapes. The results of our study indicate that damages from bird and rodents remain high for many crops and are likely to be economically significant within the state of California.  相似文献   
4.

The scale of damage caused by vertebrates to the plastic wrap on baled silage was evaluated on Irish farms. A survey was conducted on 300 farms representative of farming systems and geographical locations throughout Ireland. The scale of damage was classified as farms with 0%, 1-10%, 11-50% or 51-100% of bales with holes in the plastic wrap caused by birds. The proportion of farms within these four classes with damage caused by birds during the short interval between wrapping and removal from the field to storage was 47%, 37%, 15% and 1% of the total, respectively. Correspondingly, during the subsequent storage prior to feedout, bird damage was 37%, 50%, 12%, and 1%. Similarly, the proportions for damage throughout long-term storage due to cats were 71%, 23%, 6% and 0%, while the incidence of damage caused by rats, dogs and farm livestock was comparatively small. The stored bales were fenced against livestock on 86% of farms, while netting, bale painting and other protection methods were used to discourage damage on 2%, 17% and 9% of farms, respectively. The damage caused by birds was more prevalent on farms where the bales were stored on their curved side rather than their flat end, more than twotiers high and in farmyards rather than in fields. Cats damaged the sides and shoulders of the peripheral bales within bale collections, particularly where wrapped bales were stored in the farmyard.  相似文献   
5.
据调查,湖北万朝山自然保护区分布有珍稀濒危野生脊椎动物77种,占保护区脊椎动物257种的29.96%,其中兽类21种,鸟类43种,爬行类7种,两栖类6种。国家重点保护野生动物56种,中国濒危动物红皮书物种39种,国际贸易公约濒危野生动物61种。  相似文献   
6.
Moran  Shmuel 《Phytoparasitica》2003,31(2):109-117
The checklist of vertebrate pest species responsible for economic damage to agriculture production in Israel, which was first published in 1993, has been updated for 1993–2001. During this period new crop types have been damaged by these pests, and they have been added to the checklist. Four new bird pest species were also added:Carduelis chloris, Anas platyrhinchos, Larus ridibundus andPelecanus onocrotalus. Thus the number of economically significant vertebrate species is now 65 (27 mammalian, 36 avian and two reptilian species). Cases of depredation in forestry and pasture, which were not included in the former list, were also added. The significance of the compiled data in assisting with farm management decision is also discussed. http://www.phytoparasitica.org posting Jan. 29, 2003.  相似文献   
7.
本文以蟾蜍(两栖纲)、扬子鳄(爬行纲)、鹌鹑(鸟纲)、家兔(哺乳纲)的肾、肝、心脏3种组织为材料,采用聚丙烯酰胺圆盘电泳,获得了相应组织的乳酸脱氢酶的电泳酶谱和扫描曲线图。结果表明,不同纲的脊椎动物之间及不同组织之间的乳酸脱氢酶的种类、活性大小有一定差异,但与脊椎动物系统演化之间无明显平行关系。  相似文献   
8.
In the past decade, there has been growing concern about the rapid degradation of marine ecosystems due to anthropogenic causes. Consequently, identifying priority areas for the conservation of marine biodiversity has become a crucial conservation issue. Taking into account the influence of human population density, we performed complementarity analyses to identify priority areas for the conservation of all coastal marine vertebrate species in Chile (265 species), and evaluated congruence among the different target groups. The distribution ranges of all species were digitized in a geographic information system and analyses were performed on latitudinal bands of 0.5°. Our results show that 12 latitudinal bands (∼16% of all latitudinal bands) are necessary to conserve at least one population of each species. Ten of these bands are irreplaceable, whereas two are flexible. Many of the irreplaceable sites lie within areas that have high human population density. In order to conserve all threatened and endemic species, six and three latitudinal bands are needed, respectively. Four latitudinal bands are needed to represent all species of fish, reptiles, and mammals, whereas nine bands are needed to protect all bird species. Taking flexible sites into account, reserve networks that meet the minimum representation goal for each taxonomic group, and for threatened and endemic species, represent subsets of the 12 latitudinal band network selected for all species. Spatial congruence among reserve networks selected for each target group was relatively low and only significantly higher than random in 9 out of 21 pairwise comparisons. However, with the exception of reptiles, conservation areas selected for different surrogate groups represented other groups relatively well, compared to randomly selected sites.  相似文献   
9.
Over the past few decades, there has been a steep increase in the number of conservation-related field studies that measure glucocorticoid hormones (corticosterone or cortisol) as a marker for stress. Endocrine tools show great potential for informing conservation, however interpretation of results is often complicated. This paper reviews the role of glucocorticoids for non-physiologists, evaluates select applications of glucocorticoid measures to conservation field studies, and proposes a theoretical model to focus future research. Because levels of glucocorticoids typically increase in response to challenge and sometimes predict mortality or decrease reproduction, it is often assumed that high levels of glucocorticoids indicate stress. However, literature review suggests that glucocorticoid measures fail to change consistently in a predictable manner with adverse conditions and do not always show a linear correlation with survival or reproductive success. Inconsistencies relate in part to methodological problems but also have a physiological basis. We propose that relationships between (1) glucocorticoids and fitness and (2) glucocorticoids and disturbance may be more log quadratic rather than linear. We hope these models will be useful in generating predictions for future studies and resolving the inconsistencies that currently complicate interpretation for conservation endocrinologists.  相似文献   
10.
Five members of the order Carnivora in the cool-temperate deciduous forests of Japan consume the fruits of trees, and they are potential dispersers of the seeds of fleshy-fruited plants. We studied the frugivory of the Asiatic black bear, Japanese marten, badger, red fox, and raccoon dog in cool-temperate deciduous forest of central Japan. From May 2003 to April 2005, a total of 377 fecal samples of the five carnivores (bears, 91; martens, 158; badgers, 45; foxes, 36; and raccoon dogs, 47) were sampled to determine the presence and frequency of occurrence of seeds. Seeds from 17 plant species, representing about 50% of the fleshy-fruited plants occurring in the study forest, were recovered from the carnivore fecal samples. Large numbers (9–10,256) of seeds were present in those feces. Almost all the seeds of fleshy fruits retrieved from the fecal samples were undamaged whereas no intact acorns or nuts were recovered. These findings suggest that all five carnivores can act as seed dispersers for some fleshy-fruited plants in cool-temperate deciduous forest. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   
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