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671.
Neumann EJ Grinberg A Bonistalli KN Mack HJ Lehrbach PR Gibson N 《Veterinary microbiology》2009,138(3-4):297-303
The porcine reproductive and respiratory syndrome virus (PRRSV) is an enveloped RNA virus. Virions of PRRSV contain six membrane proteins: the major proteins GP5 and M and the minor proteins GP2, GP3, GP4, and E. The GP5 is the major envelope proteins, which was involved in the formation and infectivity of PRRSV by coaction with other membrane proteins. Here, to determine the function of alone GP5 envelope protein in viral entry, we investigated the formation and infectivity of GP5-pseudotyped virus particles. By co-transfection of GP5 expression plasmids with murine leukemia virus (MuLV) based retroviral vectors (pHIT60, encoding MuLV Gag-Pol; pHIT111, encoding an MuLV genome with a β-galactosidase reporter gene) into 293 T cells and analysis of the culture medium using ultracentrifugation, Western blot, and infection assay. We observed that the GP5 envelope protein was incorporated into the MuLV retroviral vectors to generate an pseudotyped murine leukemia virus, which was infectious to PAM and Mack-145 target cells and displayed the same host range with wild-type PRRSV. The infection of the pseudotyped virus on PAM target cells is effectively neutralized by polyclonal antibodies specific for PRRSV or GP5. The results suggested that the GP5 protein may play a key role in the viral entry by interacting with the host cell receptor. The GP5-pseudotyped virus will be useful in the identification of the cellular receptor binding with GP5 protein. 相似文献
672.
Madrazo J García-Fernández RA García-Iglesias MJ Durán AJ Espinosa J Pérez-Martínez C 《Veterinary journal (London, England : 1997)》2009,180(3):371-376
CD44 is an adhesion molecule implicated in the progression of human breast cancer. The purpose of this study was to describe CD44 antigen expression in canine mammary carcinomas and to evaluate its prognostic significance in relation to other clinico-pathological variables.A reduction in CD44 expression was significantly related to variables such as tumour size and adherence to underlying tissues but was not related to tumour location or to ulceration of the overlying skin. Complex (grade I) and anaplastic (grade III) carcinomas exhibited more intense expression of this antigen than did some tubulopapillary and most solid carcinomas (grade II). Although reduced CD44 expression was associated with infiltrative growth and vascular invasion in solid carcinomas, intense expression was also observed in anaplastic tumours. Although overall these findings suggest a role for this adhesion factor in canine mammary tumour development and progression, the complexity and apparently paradoxical nature of some of the findings currently limit the use of this immunohistochemical marker as a prognostic indicator. 相似文献
673.
Lori M MacDougall DVM James A Hethey BSc Alex Livingston† BSc BVetMed PhD Diplomate ECVPT FRCVS Christopher Clark‡ BA VetMB MVetSc Diplomate ACVIM Cindy L Shmon DVM MVSc Diplomate ACVS & Tanya Duke-Novakovski BVetMed DVA Diplomate ACVA Diplomate ECVAA 《Veterinary anaesthesia and analgesia》2009,36(5):512-522
674.
Frank Coopman Stefaan De Smet Hans Laevens Alex Van Zeveren Luc Duchateau 《Livestock Science》2009,125(2-3):318-322
Live weight is an important trait in cattle farming. Weighing is not always feasible and therefore live weight is often estimated from easily accessible data. In this study, data on live weight, age and gender, and four body measurements, withers height (WH), heart girth (HG) and width of the shoulders (SW) and hind quarters (BcW) of double-muscled Belgian Blue beef (DM-BBB) farm animals were used to develop multivariable non-linear and linear regression models that predict live weight from these easily accessible data. The relationship between the logarithm of the live weight and the logarithm of time is adequately described by a general logistic function. The age period from 100 to 600 days of age is contained in the linear part of the logistic function. This region is of particular economic interest because it contains the yearling age and slaughter age that are important in DM-BBB breeding and management. Adding one of the body traits in the linear models that contain age and gender as fixed effects decreases the coefficient of variation. A model with withers height and shoulder width has the lowest coefficient of variation, with no further significant improvement when adding either heart girth or width of the hind quarters. 相似文献
675.
Metolachlor is one of the most widely used herbicides in the world for controlling weeds. It has been detected in both ground and surface waters in the United States, and there are rising concerns in regard to its health risks and in developing effective treatment processes for its removal from water. Degradation of metolachlor via ultraviolet (UV) photolysis and an UV/hydrogen peroxide advanced oxidation process (AOP) was studied. The quantum yield of metolachlor at 254 nm was found to be 0.302 +/- 0.001 mol E-1 through direct UV photolysis in the range of pH 6-8. The second-order rate constant of the reaction between metolachlor and hydroxyl radical was determined to be 9.07 (+/-0.21) x 10(9) M-1 s-1 by using a competition kinetics model that utilized nitrobenzene as a reference compound. In addition, these parameters were successfully applied in modeling the kinetics of elimination of metolachlor using an UV/H2O2 process in both laboratory and natural waters. The formation of several photolysis byproducts was identified using gas chromatography/mass spectrometry, and a scheme for the metolachlor photodegradation pathway is proposed. 相似文献
676.
677.
Walsh T McClellan JM McCarthy SE Addington AM Pierce SB Cooper GM Nord AS Kusenda M Malhotra D Bhandari A Stray SM Rippey CF Roccanova P Makarov V Lakshmi B Findling RL Sikich L Stromberg T Merriman B Gogtay N Butler P Eckstrand K Noory L Gochman P Long R Chen Z Davis S Baker C Eichler EE Meltzer PS Nelson SF Singleton AB Lee MK Rapoport JL King MC Sebat J 《Science (New York, N.Y.)》2008,320(5875):539-543
Schizophrenia is a devastating neurodevelopmental disorder whose genetic influences remain elusive. We hypothesize that individually rare structural variants contribute to the illness. Microdeletions and microduplications >100 kilobases were identified by microarray comparative genomic hybridization of genomic DNA from 150 individuals with schizophrenia and 268 ancestry-matched controls. All variants were validated by high-resolution platforms. Novel deletions and duplications of genes were present in 5% of controls versus 15% of cases and 20% of young-onset cases, both highly significant differences. The association was independently replicated in patients with childhood-onset schizophrenia as compared with their parents. Mutations in cases disrupted genes disproportionately from signaling networks controlling neurodevelopment, including neuregulin and glutamate pathways. These results suggest that multiple, individually rare mutations altering genes in neurodevelopmental pathways contribute to schizophrenia. 相似文献
678.
- The coastal marine protected ecosystem at Punta Coles (as a part of the Reserva Nacional de Islas, Islotes y Puntas Guaneras) is located in a highly exploited area in southern Peru and contains several commercial, bioengineering and other benthic species.
- Pre-image population analysis was used to estimate the transient values of intrinsic growth rate (r) based on biomass and density time series as a proxy of productivity to assess the effectiveness of protection.
- The outcomes obtained showed that the gastropods Concholepas concholepas, Fissurella latimartiginata and the tunicate Purya chilensis showed a reduction of productivity during recent years, whilst the sea urchin Loxechinus albus, the barnacle Balanus laevis and the bivalve Semimytilus algosus showed an opposite pattern. Several species exhibited a chaotic dynamic, coinciding with the highest productivity values. In 2016 and 2017, several species exhibited a reduction of their abundance which could be delayed responses explained by changes in oceanographic conditions (reduction of coastal upwelling), La Niña event and illegal harvest.
- The above notwithstanding, the results suggest that effective protection of benthic species in the protected ecosystem of Punta Coles have been partially accomplished. Therefore, this work could be considered a baseline study, permitting the subsequent monitoring of productivity of the main species inhabiting the coastal area of Punta Coles.
- Pre-image population analysis could be used as a complimentary analytical tool since it enables the evaluation of transient population parameters (e.g. productivity) thus aiding population management, conservation and monitoring decisions.