Gastrointestinal nematode control programs with an emphasis on cattle.     

Bert E Stromberg  Louis C Gasbarre 《Veterinary Clinics of North America: Food Animal Practice》2006,22(3):543-565

Control strategies for nematode parasites rely on knowledge of the relationships between the parasites and their hosts. Specifically, these programs are based on identifying crucial points of interaction in the environment provided by the host, including genetics and the immune response, and critical periods in the physical environment in which the eggs and larval stages must develop. When these targets are identified and the interactions understood, cost-effective sustainable programs can be developed using currently available antiparasitic compounds. Resistance to the major classes of anthelmintic compounds requires consideration of new approaches, such as immunity or genetics of the host. Additionally, the efficacy of these compounds can be expanded with combined or concomitant use. Increased study of the use of novel approaches, including fungi, elements such as copper, and plant products, has also occurred. This article explores each of these areas to allow readers to appreciate how various approaches may be developed and incorporated into an effective parasite control program.  相似文献   

Granulomatous lesions in lymph nodes of slaughter pigs bacteriologically negative for Mycobacterium avium subsp. avium and positive for Rhodococcus equi     

Komijn RE  Wisselink HJ  Rijsman VM  Stockhofe-Zurwieden N  Bakker D  van Zijderveld FG  Eger T  Wagenaar JA  Putirulan FF  Urlings BA 《Veterinary microbiology》2007,120(3-4):352-357

The prevalence of granulomatous lesions in lymph nodes of pigs was studied. From January till August 2004 in two slaughterhouses in The Netherlands 2,116,536 pigs were examined for the presence of granulomatous lesions in the sub-maxillary lymph nodes. In 15,900 (0.75%) of these pigs, lesions could be detected. Nine farms with the highest incidence of lesions were selected for a more detailed pathological and bacteriological examination. On these farms, the prevalence of lesions in sub-maxillary lymph nodes ranged from 2.3 to 5.7% with a mean of 3.0%. From 1276 pigs that were sampled, 98 (7.7%) displayed granulomatous lesions in the sub-maxillary lymph nodes and one (0.1%) pig showed lesions in its mesenteric lymph node. Mycobacterium avium subsp. avium (MAA) could not be isolated from the lymph nodes of the 99 pigs with lesions and from a selection of lymph nodes (n = 61) of pigs without lesions. Rhodococcus equi was isolated from 44 out of 98 (44.9%) of the sub-maxillary lymph nodes with granulomatous lesions and from two mesenteric lymph nodes without lesions. A comparison of former studies and the current results indicate that the prevalence of MAA infections in slaughter pigs has strongly decreased over the last decade, whereas R. equi is highly prevalent. The high incidence of granulomatous lesions associated with the bacteriological presence of R. equi could be considered as a serious cause of misdiagnosis of MAA infections in cases where meat inspection is carried out by inspection for granulomatous changes of lymph nodes only.  相似文献   

Stability and profiling of urinary microRNAs in healthy cats and cats with pyelonephritis or other urological conditions     

Lisbeth R. Jessen  Lise N. Nielsen  Ida N. Kieler  Rebecca Langhorn  Bert J. Reezigt  Susanna Cirera 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2020,34(1):166-175

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AAAS Meetings: A Progress Report     

Bert WG 《Science (New York, N.Y.)》1969,163(3869):767

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The sudden death of a coral reef     

Hoeksema BW  Cleary DF 《Science (New York, N.Y.)》2004,303(5662):1293-4; author reply 1293-4

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Distributions of microbial activities in deep subseafloor sediments   总被引：1，自引：0，他引：1  

D'Hondt S  Jørgensen BB  Miller DJ  Batzke A  Blake R  Cragg BA  Cypionka H  Dickens GR  Ferdelman T  Hinrichs KU  Holm NG  Mitterer R  Spivack A  Wang G  Bekins B  Engelen B  Ford K  Gettemy G  Rutherford SD  Sass H  Skilbeck CG  Aiello IW  Guèrin G  House CH  Inagaki F  Meister P  Naehr T  Niitsuma S  Parkes RJ  Schippers A  Smith DC  Teske A  Wiegel J  Padilla CN  Acosta JL 《Science (New York, N.Y.)》2004,306(5705):2216-2221

Diverse microbial communities and numerous energy-yielding activities occur in deeply buried sediments of the eastern Pacific Ocean. Distributions of metabolic activities often deviate from the standard model. Rates of activities, cell concentrations, and populations of cultured bacteria vary consistently from one subseafloor environment to another. Net rates of major activities principally rely on electron acceptors and electron donors from the photosynthetic surface world. At open-ocean sites, nitrate and oxygen are supplied to the deepest sedimentary communities through the underlying basaltic aquifer. In turn, these sedimentary communities may supply dissolved electron donors and nutrients to the underlying crustal biosphere.  相似文献   

The structure of a human p110alpha/p85alpha complex elucidates the effects of oncogenic PI3Kalpha mutations     

Huang CH  Mandelker D  Schmidt-Kittler O  Samuels Y  Velculescu VE  Kinzler KW  Vogelstein B  Gabelli SB  Amzel LM 《Science (New York, N.Y.)》2007,318(5857):1744-1748

PIK3CA, one of the two most frequently mutated oncogenes in human tumors, codes for p110alpha, the catalytic subunit of a phosphatidylinositol 3-kinase, isoform alpha (PI3Kalpha, p110alpha/p85). Here, we report a 3.0 angstrom resolution structure of a complex between p110alpha and a polypeptide containing the p110alpha-binding domains of p85alpha, a protein required for its enzymatic activity. The structure shows that many of the mutations occur at residues lying at the interfaces between p110alpha and p85alpha or between the kinase domain of p110alpha and other domains within the catalytic subunit. Disruptions of these interactions are likely to affect the regulation of kinase activity by p85 or the catalytic activity of the enzyme, respectively. In addition to providing new insights about the structure of PI3Kalpha, these results suggest specific mechanisms for the effect of oncogenic mutations in p110alpha and p85alpha.  相似文献   

High-probability uniquantal transmission at excitatory synapses in barrel cortex     

Silver RA  Lubke J  Sakmann B  Feldmeyer D 《Science (New York, N.Y.)》2003,302(5652):1981-1984

The number of vesicles released at excitatory synapses and the number of release sites per synaptic connection are key determinants of information processing in the cortex, yet they remain uncertain. Here we show that the number of functional release sites and the number of anatomically identified synaptic contacts are equal at connections between spiny stellate and pyramidal cells in rat barrel cortex. Moreover, our results indicate that the amount of transmitter released per synaptic contact is independent of release probability and the intrinsic release probability is high. These properties suggest that connections between layer 4 and layer 2/3 are tuned for reliable transmission of spatially distributed, timing-based signals.  相似文献   

Recognition dynamics up to microseconds revealed from an RDC-derived ubiquitin ensemble in solution     

Lange OF  Lakomek NA  Farès C  Schröder GF  Walter KF  Becker S  Meiler J  Grubmüller H  Griesinger C  de Groot BL 《Science (New York, N.Y.)》2008,320(5882):1471-1475

Protein dynamics are essential for protein function, and yet it has been challenging to access the underlying atomic motions in solution on nanosecond-to-microsecond time scales. We present a structural ensemble of ubiquitin, refined against residual dipolar couplings (RDCs), comprising solution dynamics up to microseconds. The ensemble covers the complete structural heterogeneity observed in 46 ubiquitin crystal structures, most of which are complexes with other proteins. Conformational selection, rather than induced-fit motion, thus suffices to explain the molecular recognition dynamics of ubiquitin. Marked correlations are seen between the flexibility of the ensemble and contacts formed in ubiquitin complexes. A large part of the solution dynamics is concentrated in one concerted mode, which accounts for most of ubiquitin's molecular recognition heterogeneity and ensures a low entropic complex formation cost.  相似文献   

Phenotyping of productivity and resilience in sweetpotato under water stress through UAV-based multispectral and thermal imagery in Mozambique     

David A. Ramírez  Wolfgang Grüneberg  Maria I. Andrade  Bert De Boeck  Hildo Loayza  Godwill S. Makunde  Johan Ninanya  Javier Rinza  Simon Heck  Hugo Campos 《Journal of Agronomy and Crop Science》2023,209(1):41-55

Sweetpotato is a crucial crop to guarantee food security in sub-Saharan Africa, and drought events are considered one of the most critical factors affecting sweetpotato productivity in this region. In this study, airborne imagery based on reflectance (NDVI, CI_red-edge) and canopy temperature minus air temperature (dT) indices was used to characterize sweetpotato genotypes under drought treatments in Mozambique. Two field experiments established in rainy/hot (Trial A) and dry/cool (Trial B) seasons were assessed. In Trial A, 24 genotypes were subjected to early- (ESD), mid- (MSD) and late-season (LSD) drought stress treatments and compared against a control. In Trial B, 120 genotypes were subjected to LSD only. The percentage of reduction in vine weight (PR_VW) under drought was related primarily to temporal variation of NDVI and CI, regardless of drought treatment and seasons. dT in relation to control (dT_Amp) was associated with PR_VW in ESD-Trial A and LSD-Trial B, whereas under LSD-Trial A, dT_Amp was related to total fresh storage root weight (TRW). During the rainy/hot season, higher TRW reduction was promoted under ESD; however, under LSD, it was possible to identify productive genotypes able to withstand drought stress, highlighting their relevance for drought-tolerance selection purposes.  相似文献