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排序方式: 共有431条查询结果,搜索用时 31 毫秒
101.
Amat M Manteca X Brech SL Ruiz de la Torre JL Mariotti VM Fatjó J 《Journal of the American Veterinary Medical Association》2008,233(4):586-589
OBJECTIVE: To identify inciting causes, alternative targets, and risk factors associated with redirected aggression in cats. DESIGN: Case-control study. ANIMALS: 19 cats with a history of redirected aggression and 64 cats with no such history. PROCEDURES: Medical records were reviewed to identify cats evaluated for problems with redirected aggression (case cats), in which the primary inciting stimulus and alternative target of aggression were clearly identifiable. Data obtained from the records and from follow-up interviews included details about the cats and incidents of redirected aggression. Owners of control cats were interviewed via telephone to obtain similar information on their cats. RESULTS: 22 incidents of redirected aggression were reported for the 19 case cats. In 95% of those incidents, loud noises or interactions with other cats were identified as the inciting stimuli. Case cats most commonly redirected their aggression toward the owner, followed by another cat living in the same household. Compared with control cats, case cats were more likely to have a sound phobia but were less likely to be outdoor cats. In addition, case cats were more likely to be from small households (相似文献
102.
Tabar MD Altet L Francino O Sánchez A Ferrer L Roura X 《Veterinary parasitology》2008,151(2-4):332-336
Previous serological surveys have reported the presence of different organisms in cats from Spain but little reports exist about the exact identity of these organisms. The purpose of the study reported here was to assess the presence of DNA of several vector-borne infections in a population of cats from Barcelona area. One hundred blood samples obtained from cats admitted to the UAB-VTH were entered into the study and classified as healthy (n=48) or unhealthy (n=52). EDTA-blood samples were assayed for Leishmania infantum, Ehrlichia spp., Anaplasma spp., Rickettsia spp., Bartonella spp., Hepatozoon spp., Babesia spp. and Theileria spp. DNA by means of PCR amplification and amplicons obtained were sequenced. Prevalence of infectious agents found were Leishmania infantum (3%), Ehrlichia/Anaplasma sp. (1%), Hepatozoon felis (4%) and Bartonella clarridgeiae (1%). Cats being less than 5 years old had more probability of having at less one PCR positive result (P=0.028). The results of this study show a low prevalence of several vector-borne pathogens among cats from Barcelona area. Although higher feline seroprevalences are previously reported, they evidenced exposure and probably overestimate the real or active degree of infection. However, it is important to maintain a high index of suspicion on these infectious diseases, both in sick and asymptomatic cats, and molecular techniques could aid in the identification of these pathogens. 相似文献
103.
Modification of soil porosity after application of sewage sludge 总被引:1,自引:0,他引:1
The effect of the application of sewage sludge on soil porosity over 28 months is discussed here. Anaerobic sludges of urban refuse waters were applied on a degraded limestone soil in a mining land by two ways. First, a previous mixture of sludge and soil was carried out; this was then applied to the target land. Second, a direct application of sludge to soil and tilling. Porosity and pore morphology were measured on thin sections prepared from undisturbed soil samples. Data were obtained from backscattered electron images and image-processing computer equipment. The application of sludge induced an increase of both soil fine microporosity (φ<50 μm) and coarse microporosity (φ>50 μm). However, this effect showed transient, since no significant differences were reported in relation to the control plot after one year from application. The incorporation of sludge and developed vegetation modified coarse micropore irregularity and orientation. On the other hand, fine micropore morphology remains unchanged. 相似文献
104.
Antonio Box Xavier Capó Silvia Tejada Antoni Sureda Laia Mejías José María Valencia 《Journal of fish diseases》2020,43(1):1-7
Perkinsus mediterraneus is a protozoan parasite that can cause marine mollusc diseases known as perkinsosis being a serious threat for clam cultures worldwide. The aim of the present study was first to determine the Perkinsus species infecting the variegated scallop Mimachlamys varia and then to evaluate the existence of oxidative stress in gills of M. varia according to different degrees of infection. DNA sequencing confirmed that P. mediterraneus was the species infecting M. varia. ROS production was progressively increasing with the degree of infection although the differences were only significant in the high-infected group. Low degree of infection significantly increased superoxide dismutase (SOD) and glutathione S-transferase (GST) activities and nitrite levels with respect to the control group. In the high-infected group, a significant increase was evidenced in all analysed enzymes, catalase, SOD, glutathione reductase and GST. Non-significant differences in MDA levels were observed between the control and low-infected groups; however, a significant increase in MDA levels was observed in the high-infected group. In conclusion, the infection by Perkinsus mediterraneus in M. varia induces oxidative stress and an antioxidant response directly related to the infection degree that can contribute to the pathogenicity of the infection. 相似文献
105.
Amanda Mara Teles Leticia Prince Pereira Pontes Sulayne Janayna Araújo Guimares Ana Luiza Butarelli Gabriel Xavier Silva Flavia Raquel Fernandes do Nascimento Geusa Felipa de Barros Bezerra Carla Junqueira Moragas-Tellis Rui Miguel Gil da Costa Marcos Antonio Custdio Neto da Silva Fernando Almeida-Souza Ktia da Silva Calabrese Ana Paula Silva Azevedo-Santos Maria do Desterro Soares Brando Nascimento 《Marine drugs》2020,18(11)
Background: This study addresses the antitumoral properties of Penicillium purpurogenum isolated from a polluted lagoon in Northeastern Brazil. Methods: Ethyl Acetate Extracellular Extract (EAE) was used. The metabolites were studied using direct infusion mass spectrometry. The solid Ehrlich tumor model was used for antitumor activity. Female Swiss mice were divided into groups (n = 10/group) as follows: The negative control (CTL−), treated with a phosphate buffered solution; the positive control (CTL+), treated with cyclophosphamide (25 mg/kg); extract treatments at doses of 4, 20, and 100 mg/kg; animals without tumors or treatments (Sham); and animals without tumors treated with an intermediate dose (EAE20). All treatments were performed intraperitoneally, daily, for 15 days. Subsequently, the animals were euthanized, and the tumor, lymphoid organs, and serum were used for immunological, histological, and biochemical parameter evaluations. Results: The extract was rich in meroterpenoids. All doses significantly reduced tumor size, and the 20 and 100 mg/kg doses reduced tumor-associated inflammation and tumor necrosis. The extract also reduced the cellular infiltration of lymphoid organs and circulating TNF-α levels. The extract did not induce weight loss or renal and hepatic toxic changes. Conclusions: These results indicate that P. purpurogenum exhibits immunomodulatory and antitumor properties in vivo. Thus, fungal fermentation is a valid biotechnological approach to the production of antitumor agents. 相似文献
106.
Foltête Jean-Christophe Savary Paul Clauzel Céline Bourgeois Marc Girardet Xavier Sahraoui Yohan Vuidel Gilles Garnier Stéphane 《Landscape Ecology》2020,35(5):1035-1052
Landscape Ecology - Landscape graphs are widely used to model networks of habitat patches. As they require little input data, they are particularly suitable for supporting conservation decisions... 相似文献
107.
Neus Morera Xavier Valls Joan Mascort 《Veterinary Clinics of North America: Exotic Animal Practice》2006,9(3):667-671
This case report describes the diagnosis and resolution of an inter-vertebral disk prolapse in a 6-year-old ferret. No predisposing causes were found in the patient's history. A right hemilaminectomy, performed 1 week after presentation, was chosen to treat the patient surgically, and complete remission of clinical signs was achieved 2 months after presentation. 相似文献
108.
Aziz Tnibar DVM PhD Dipl. ECVS Ahmed Tibary DVM PhD Dipl. ACT Lilia Boulouha DVM Xavier Ribot DVM 《Journal of Equine Veterinary Science》2006,26(8):370-375
This article describes atypical interstitial (Leydig) cell tumors in two cryptorchid horses. Ultrasonography allowed accurate localization of the cryptorchid testicles. Ultrasonographic features of the tumor are also presented and may be of value for the clinical diagnosis.Histopathological evaluation of testicular tissue after cryptorchidectomy revealed atypical evolving interstitial (Leydig) cell tumors. Clinically, the tumors reported here appear to have several similarities with the interstitial (Leydig) cell tumors described in the literature, which in most cases appear to be (1) cryptorchidism–induced tumors, (2) often benign and not enlarged, and (3) often associated with aggressive behavior. Although generally considered to be uncommon, equine testicular neoplasms may occur more frequently than previously thought. The use of ultrasonography may improve diagnosis. 相似文献
109.
110.
Dominance of a resistance trait can be defined as a measure of the relative position of the phenotype of the heterozygote RS compared with the phenotype of the two corresponding homozygotes, SS and RR. This parameter has been shown to have primary importance in the dynamics of pesticide resistance evolution. Literature on insecticide resistance suggests that dominance levels in the presence of insecticide vary greatly from completely recessive to completely dominant. With insecticides, both the chemical applied and the dosages used have been demonstrated to affect the dominance. By contrast, almost all herbicide resistances have been found to be inherited as partially to totally dominant traits. This discrepancy between weeds and insects may partly result from the methodologies applied to measure the dominance, ie a single dose for herbicide versus several doses for insecticide. Using two well-known resistances (csr1-1 and csr1-2) to acetolactate synthase (ALS) inhibitors in Arabidopsis thaliana (L) Heynh (mouse-ear cress), we used several herbicide doses to determine the dominance level to six ALS-inhibiting herbicides. The dominance level in the presence of herbicide varied from completely dominant to completely recessive, depending on the resistance allele and the herbicide tested. The dominance of the csr1-1 and csr1-2 resistance alleles ranged from 0 (completely recessive) to 1.1 (dominant) and from 0 to 0.3 (partially dominant), respectively. The recessivity of some resistance alleles in the presence of herbicide could lead to the development of improved resistance management in order to delay or avoid herbicide resistance evolution, especially in the control of outcrossing weed species. 相似文献