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1.
Doxorubicin continues to be one of the most widely used anticancer agents in the clinic despite its dose-limiting side-effects. Many of doxorubicin's dose-limiting toxicities occur due to its generation of toxic oxygen species, resulting in oxidative stress. Some clinical observations have suggested that doxorubicin may have greater toxicity in older patients. The studies presented here compare basal and doxorubicin-induced antioxidant enzyme activities in brain, heart, kidney and liver tissues of Fisher 344 rats of different ages to determine whether differences in these enzymes can account for the age-dependent differences observed in doxorubicin-induced toxicity. Three groups of animals were tested, young animals (2-months-old), adult animals (10-months-old) and old animals (18-months-old). The results of these studies show that in general young and adult animals have similar levels of antioxidant enzyme activity while the older animals have less. Only in the young animals is antioxidant enzyme activity significantly increased following doxorubicin treatment suggesting that enzyme induction occurs only in the young group of animals. Lipid peroxidation is shown to have the greatest increase in the old animals following doxorubicin treatment while the young animals have the smallest increase. The results from these studies suggest that there is an increase in doxorubicin-induced oxidative damage with age and that these differences may be due to basal and drug-induced differences in tissue antioxidant enzyme activities. 相似文献
2.
动物可分为野生动物和家养动物,越来越多的野生动物被人们当作宠物来饲养。野生动物作为宠物的危害是巨大的。野生动物对人类的危害主要包括直接攻击人类,携带病原威胁人类以及对环境设施造成的破坏。人类对野生动物的危害包括野生动物驯养繁殖、疾病传播等方面。野生动物对家养动物的危害包括直接危害和疾病危害。因此,野生动物不适合作为宠物饲养,不仅仅是因为它们原本的生活习性,对野生动物资源的破坏,更重要的是病原体可能跨越种间障碍而威胁人类的安全。 相似文献
3.
The effects of selection for a type of behavior relative to humans (tame and aggressive) on the intensity of coat color in agouti rats with the AAHH genotype were studied. Animals that were not under selection for behavior (wild animals) were used as the control. Morphometric analysis of the hair parameters that influence the intensity of coat color demonstrated that, on the one hand, polymorphism in the main coat color exists in the population of wild agouti rats, that is, both light and dark agouti animals exist. On the other hand, it was demonstrated that selection for a type of behavior in rats is accompanied by selection of animals that differ in the intensity of the main genetically identical coat color. Dark-colored animals are more prevelent among the aggressive animals, while light-colored animals prevail among tame animals. The association of the effects of selection for behavior with the modification of coat color is probably caused by the presence of common neurohormonal mechanisms for the regulation of these processes. 相似文献
4.
J C Coppes E L Bradley 《Comparative biochemistry and physiology. A, Comparative physiology》1984,78(2):297-306
Exogenous ACTH will cause adrenal hypertrophy and gonad dysfunction in reproductively capable male deermice. The ultrastructure of the zona fasciculata of inhibited animals is substantially different from ACTH stimulated animals which suggests that ACTH alone does not produce the inhibition. Although ACTH concentrations were variable, there was no clear demonstration that any differences existed between reproductively capable vs inhibited animals at the time when corticosterone is known to be elevated in the inhibited animals. A contributory role for ACTH in promoting inhibition is not ruled out, but neither is it likely that elevated ACTH alone accounts for the observed reproductive inhibition in animals taken from populations. 相似文献
5.
There is a direct, linear relationship between scaphognathie beat frequency and absolute ventilation volume in Carcinus maenas (L). The absolute ventilation volume is directly proportional to the size of the animals. At all scaphognathie frequencies small animals have a greater relative ventilation volume than large animals. The absolute stroke volume (ml/beat) is greater in large animals than in small animals. The majority of the available evidence suggests that, whilst the force of the scaphognathie stroke may be variable, the amplitude of its excursion remains constant at all beat frequencies. 相似文献
6.
Nelly Mäekivi 《Biosemiotics》2016,9(2):207-226
Communication and behaviour of animals living ex situ has been one of the major sources of knowledge about wild animals. Nevertheless, it is also acknowledged that depending on the environment that the animals inhabit (or are kept in), there are differences in their communication and behaviour. With some species (especially large mammals) it is difficult to reproduce their natural environment to an extent that excludes deviations from the behaviour and communication exhibited by animals living in situ. In zoological gardens, welfare measures are introduced in order to counteract the effects of the captive environment and to grant an individual’s good physical and psychological well-being. The relation between good welfare and species-specific communication and behaviour is discussed, and as a result, a general model of ex situ animal communication and behaviour is proposed. The suggested model is inclusive of differences between captive animals and free-ranging animals and serves to explain the welfare-related reasons underlying individual animal’s deviations from species-specific behaviour and communication. 相似文献
7.
Pamela L. Pannozzo Kimberley A. Phillips† Meghan E. Haas† & Eric M. Mintz‡ 《Ethology : formerly Zeitschrift fur Tierpsychologie》2007,113(9):881-888
In several studies of social monitoring in primates, subordinate animals directed more visual attention toward dominant animals than vice versa. This behavior is thought to enable subordinate animals to avoid conflict. We sought to clarify whether visual attention behavior functions in this manner in a small captive group of brown capuchin monkeys, Cebus apella. We tested the hypothesis that social monitoring is related to dominance status. Dominance status was determined based on the directionality of aggressive behavior, and visual attention was quantified by using focal animal sampling. Subordinate animals directed significantly more visual attention toward others than dominant animals. Subordinate animals also looked more frequently at the animals that attacked them and others the most. The results indicate that social monitoring behavior in this captive group was driven by conflict‐avoidance. 相似文献
8.
《Anthrozo?s》2013,26(2):115-134
AbstractThe presence of animals has been associated with decreased physiological responses to stressors. Not all individuals respond equally to the presence of friendly animals. The current study was designed to examine whether attitudes toward animals are related to individuals' physiological responses when an animal is present. The relationship of individuals' perceptions of animals to their blood pressure and heart rate responses during verbalization in the presence of a dog were examined among urban college students (n=218). Lockwood's projective Animal Thematic Apperception Test (ATAT) was used to assess subjects' attitudes toward animals and people in scenes containing animals and identical scenes without animals. The significant period by perception interactions in analyses of variance with repeated measures revealed that cardiovascular responses to verbalization with an animal present were significantly lower for individuals who perceived scenes with animals more positively than for individuals who perceived scenes with animals present less positively. Cardiovascular responses when the dog was present were not related to perceptions of scenes without animals present. The differences in cardiovascular responses depended upon the scenes used. This study supports the view that how people perceive animals moderates their physiological responses to stressors when an animal is present. 相似文献
9.
Spontaneously hypercholesterolemic (SH) cynomolgus monkeys were identified that have average plasma cholesterol of 202 mg/dl, while that in normal monkeys is 119 mg/dl. The LDL from these SH monkeys have lower affinity for fibroblast LDL receptors in vitro. The amount of LDL2 (1.030 mean value of d 1.063 g/ml) required to displace 50% of [125I]LDL was 3.8 micrograms/ml for normal LDL2 and 6.6 micrograms/ml for SH-LDL2. The binding affinity of LDL1 (1.019 mean value of d 1.030 g/ml) was the same in normal and SH animals. LDL turnover experiments showed that the SH monkeys were comprised of two populations. Normal LDL2 was cleared much slower in two of the SH monkeys than in normocholesterolemic animals, suggesting that these two animals have an LDL receptor defect. However, LDL2 isolated from these two SH monkeys was cleared normally in normal monkeys. LDL2 isolated from two other SH monkeys is cleared slower than is normal LDL2 in normal animals, suggesting that these animals have an LDL defect. Thus, the hypercholesterolemia of these SH monkeys is associated with defective LDL catabolism; two animals appear to have functionally defective LDL receptors, and two animals appear to have functionally defective LDL. 相似文献
10.
Shuhai Xiao Michał Kowalewski Bing Shen Lin Dong Marc Laflamme 《Historical Biology》2013,25(4):433-436
Freeman (2009, 2010) argue that Ediacara “faunas” should be analysed using “promorphologies” of extant animals, that rangeomorphs and erniettomorphs are colonial animals, and that Vernanimalcula is a bilaterian animal. Recent studies of Ediacara fossils have provided multiple lines of evidence that these fossils represent a sample of phylogenetically diverse marine organisms that included crown-group animals as well as stem-group animals and non-animals. Thus, it is inappropriate to analyse Ediacara fossils using “promorphologies” of extant animals. The interpretation of rangeomorphs and erniettomorphs as colonial animals is inconsistent with the functional morphologies of these Ediacara fossils. Although Vernanimalcula is a fossil, the purported germ layers of Vernanimalcula are of diagenetic origin and there is no morphological evidence in support of its bilaterian affinity. 相似文献
11.
Genetically related susceptibility for experimental autoimmune myasthenia gravis was investigated in nine inbred strains of rats immunized with heterologous acetylcholine (AChR) from Torpedo californica. Wistar Munich and Fischer strain animals consistently developed severe, fatal disease associated with impaired neuromuscular transmission and increased sensitivity to low doses of curare. A lower incidence of disease was induced in Wistar Kyoto, ACI, Brown Norway, Buffalo, and Lewis strain animals. In contrast, Wistar Furth and Copenhagen strain animals were resistant to experimental autoimmune myasthenia gravis, electrophysiologic responses were normal, and animals were insensitive to curare. All strains of animals manifested equivalent amounts of serum antibody to AChR and total muscle AChR was reduced to the same extent in both resistant and susceptible animals. In contrast, the amount of antibody-bound AChR was greater in susceptible Wistar Munich animals than the amount observed in resistant Wistar Furth animals. These data suggest that impaired neurotransmission is correlated with the extent of antibody binding to the AChR. The discordance in the amount of antibody bound to the AChR of resistant and susceptible animals may result from heritable differences in antibody properties. Cross-breeding experiments with Wistar Munich and Wistar Furth animals show that resistance for development of experimental autoimmune myasthenia gravis is recessive and indicate that disease susceptibility is linked to one or two genetic loci. 相似文献
12.
Bingtao Su 《Anthrozo?s》2018,31(2):179-194
Ethical ideologies, which include dimensions of idealism and relativism, are often involved in the process of decision-making regarding operational and economic research. However, the study of the role of ethical ideologies concerning public attitudes toward animals has been largely neglected. The present study analyzed how ethical ideologies and their interaction with human demographics relate to public attitudes toward animals in the Netherlands. The Ethics Position Questionnaire (EPQ) was used to assess respondents’ ethical ideologies and their relationship with attitudes toward animals, which were measured by the Animal Issue Scale (AIS) and the Animal Attitude Scale (AAS). The results demonstrated that respondents’ gender and age were both significantly associated with attitudes toward animals, although gender showed a stronger correlation than age. Absolutists and situationists tended to show greater concern for animals than did exceptionists and subjectivists. Public attitudes toward animals were found to be significantly related to idealism; this confirms previous findings in the United States and China. Consistent with some previous findings in the United States, no significant correlation between relativism and public attitudes toward animals was found among Dutch respondents. However, this finding is inconsistent with findings in China indicating that relativism was negatively related to people’s attitudes toward animals. Our study indicates that the correlation between idealism and attitudes toward animals is the same in different countries, while the correlation between relativism and attitudes toward animals differs between developed and developing countries. 相似文献
13.
The ultrastructure of the luminal epithelium of the hedgehog uterus is described on the basis of material taken from 11 animals in three different hormonal situations: castrated, active and hibernating animals. The whole uterine epithelium is composed of microvillous cells. Its appearance is very similar in ovariectomized and hibernating animals. It differs from that observed in active animals where the epithelium is taller, microvilli are more numerous and longer, and where nuclei and cytoplasm display a very active ultrastructural appearance. The results now available indicate that ultrastructural changes occurring within the cells are certainly correlated with plasma sex steroid hormone concentrations. The present paper also reports the regular occurrence of nuclear bodies in uterine cells. 相似文献
14.
Public support is a strong impetus for the adoption of alternatives to laboratory animals. It is therefore important to find out what a society thinks about ethical animal use. In the case of China, a useful line of enquiry was to survey Chinese people's as their country is renowned for the deplorable conditions under which animals are kept. This report concerns an investigation into the attitudes of Chinese university students toward the use of animals in laboratory research. The survey revealed a moderate concern amongst students; for example, they agreed that the use of animals for testing cosmetics and household products is unnecessary and should be stopped, and disagreed that humans have the right to use animals as they see fit. This finding is very encouraging. Further research is needed, in order to understand Chinese views about the justification of using animals in research. 相似文献
15.
The change in the body and cerebellar weights, together with the quantity of RNA, DNA and proteins in the cerebellum were studied for the first 10 days and on the 12th, 14th, and 17th days of postnatal life in normal, hypo- and hyperthyroid rats. In the normal animals: (1) The average cellular protein content decreases from the first to the second day, increases to a maximum at 4 days, then decreases. (2) The specific radioactivity of the RNA, 14 h after an intravenous injection of [6-14C]orotic acid, varies distinctly from birth to 9 days and reaches two maxima at 4 and 6 days. After 9 days it decreases markedly. (3) Mitotic activity (number of replicating cells) increases, reaches a maximum at 9 days, then decreases. (4) The specific radioactivity of the DNA (used as a measure of the percentage of the cellular population in division) reaches a maximum at 6 days. (5) Mitotic efficiency (number of replicating cells in mitotic activity) decreases from 2 to 7 days, and subsequently increases. In the hypothyroid animals: (1) The average cellular protein content increases from the first to the second day and then decreases. (2) The specific radioactivity of the RNA, always significantly higher than that of normal animals, varies from birth to 9 days, reaches two maxima at 4 and 6 days, then decreases after 9 days. (3) Mitotic activity, always significantly lower than that of normal animals, increases from birth, reaches a maximum at 9 days, then decreases. (4) The specific radioactivity of the DNA reaches a maximum at 6 days and the mitotic efficiency a minimum at 7 days. Neither are significantly different from that of normal animals. In the hyperthyroid animals: (1) The average cellular protein content, is maximal at 2 days, then decreases. (2) The specific radioactivity of the RNA, always significantly lower from that of normal animals, decreases from birth. (3) Mitotic activity is similar to that of normal animals, increases from birth up to 6 days, then decreases. (4) The specific radioactivity of the DNA increases from birth up to 5 days, then decreases. It is significantly lower than that of normal animals. (5) Mitotic efficiency is significantly higher than that of normal animals. In the different groups, the maximum of the average cell size, always precedes the maximum of the cellular division. In the hypothyroid animals, the rate of cell death is higher than that of normal animals, and the average cell size is higher during the first fourteen days. In the hyperthyroid animals, the rate of cell death is lower than that of normal animals, and the average cell size is higher at 14 and 17 days. 相似文献
16.
Prospective cognition in animals 总被引:1,自引:1,他引:0
The debate about whether or not animals have foresight has focused on whether animals can be shown to have episodic future thinking, that is the ability to travel mentally in time and see themselves in the future. This focus has distracted from consideration of other forms of foresight that animals demonstrate. We propose a framework for examining future-oriented behaviours and then discuss the evidence for future thinking in animals. In the final section we examine some perspectives of future thinking and suggest that there are future-oriented capabilities of animals that do not involve mental time travel but may yet involve future thinking which deserve further investigation. 相似文献
17.
G Martino L Vetere C Covello R Filippelli A Carpino 《Bollettino della Società italiana di biologia sperimentale》1979,55(5):489-494
The Authors demonstrate that the in vitro stimulation of mitochondrial RNA synthesis produced by thyroid hormones takes place also at physiological levels, equal to those held in the liver cells of experimental animals. Two groups of male rats have been used: normal control animals (N) and animals surgically thyroidectomized on the 25th day of life (T). The animals were fed and kept in standard conditions and killed on the 85th day of life. The purification of mitochondrial samples and the determination of the mitochondrial RNA synthesis were carried out as previously described. The results suggest that the in vitro stimulation of mitocondrial RNA synthesis is already significant at the concentration of lnM. The trends are qualitatively comparable for either N or T animals. The structural analogues TRIAC (3,5,3'-triiodothyroacetic acid) and TRIPROP (3,5,3'-triiodothyropropionica acid) exhibit a clearly stimulatory effect on samples of N animals, while on samples of T animals is significant only for the first analogue. Similar trends are also observed on ADP/O ratio. 相似文献
18.
Toth E Gersner R Wilf-Yarkoni A Raizel H Dar DE Richter-Levin G Levit O Zangen A 《Journal of neurochemistry》2008,107(2):522-532
Exposure to chronic mild stress (CMS) is known to induce anhedonia in adult animals, and is associated with induction of depression in humans. However, the behavioral effects of CMS in young animals have not yet been characterized, and little is known about the long-term neurochemical effects of CMS in either young or adult animals. Here, we found that CMS induces anhedonia in adult but not in young animals, as measured by a set of behavioral paradigms. Furthermore, while CMS decreased neurogenesis and levels of brain-derived neurotrophic factor (BDNF) in the hippocampus of adult animals, it increased these parameters in young animals. We also found that CMS altered alpha-amino-3-hydroxy-5-methylisoxazole-4-propionate (AMPA) receptor GluR1 subunit levels in the hippocampus and the nucleus accumbens of adult, but not young animals. Finally, no significant differences were observed between the effects of CMS on circadian corticosterone levels in the different age groups. The substantially different neurochemical effects chronic stress exerts in young and adult animals may explain the behavioral resilience to such stress young animals possess. 相似文献
19.
松嫩草原区不同农业生态系统土壤动物群落特征 总被引:45,自引:10,他引:45
对温带松嫩草原区不同农业生态系统土壤动物群落特征进行了研究。结果表明 ,不同农业生态系统中 ,类群数为草地 >杨树林 >玉米田 ,个体数为草地 >玉米田 >杨树林。土壤动物的垂直分布存在一定差异性。玉米田土壤动物向下层聚集 ,草地具明显的表聚性 ,杨树林随着土层深度的变化较均匀。土壤动物群落的季节变化不同 ,玉米田秋季作物收割后 ,土壤动物类群明显减少 ,而杨树林秋季有增多趋势。草地土壤动物的季节变化代表了松嫩草原区土壤动物群落分布的特征。土壤动物群落的多样性为草地 >杨树林 >玉米田。分析了土壤动物与地温、土壤自然含水量、p H及土壤养分的相关性。 相似文献
20.
The potential for commercial application of transgenic technologies in domestic animals is discussed in relation to the areas
where a significant impact on agriculture might be expected. These are the endocrine system, novel biochemical pathways, structural
proteins of milk and of textile fibers, and the immune system. Manipulation of the endocrine system has been investigated
for some years and it is clear that very accurate control is needed over gene expression if this approach is to prove commercially
useful. The area most advanced in commercial application is the production of high-value pharmaceutical proteins in the mammary
glands of domestic animals. Other applications that are discussed remain to be proven in larger animals despite being demonstrated
laboratory test animals. These include a functional cysteine biosynthetic pathway and a functional glyoxylate cycle transferred
from bacteria to mice, and alterations to the proteins of hair that change the physical properties of the resultant fibers.
Research is also actively directed toward novel approaches for providing domestic animals with resistance to insects. 相似文献