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161.
This review focuses on relevant scientific information regarding the current knowledge of the yellow head complex viruses, yellow head virus and gill‐associated virus. The yellow head complex viruses have been problematic within the aquaculture industry for over 10 years and still retain their research topicality. Presently, there are numerous research papers from different journals covering the identification, disease expression and spread, pathogenesis, detection, morphology, genomic sequence and protein profiles of the yellow head complex viruses. Indeed, there has been no extensive review to compare these studies, and as a corollary, to assess flaws in contemporary research and knowledge. Additionally, the yellow head complex viruses rank within the top four prawn viruses with respect to disease impact and economic loss. This review collectively reports on all the findings and current methods of research and aims to identify weak areas of research where conclusions have been unjustifiably drawn and furthermore to elucidate areas that have a gap of knowledge. 相似文献
162.
A long-term environmental study was conducted to evaluate the significance of water temperature, pH and salinity on the prevalence of Streptococcus iniae mortalities in barramundi sea-cage facilities. It was determined that there is a strong association between temperature and increased mortality, specifically between 25 and 28 °C. Temperatures outside of that range result in decreased mortalities attributed to S. iniae. There was no statistical significance between pH or salinity and S. iniae induced mortality (p > 0.05), although acidic conditions (< pH 6) occurring due to anthropogenic disturbances did result in acute mortalities and S. iniae was recovered from approximately 70% these fish. Laboratory challenge studies confirmed the temperature dependence of S. iniae infections as well as the increased susceptibility of barramundi to S. iniae during acid water conditions. 相似文献
163.
Wilson BD Ii M Park KW Suli A Sorensen LK Larrieu-Lahargue F Urness LD Suh W Asai J Kock GA Thorne T Silver M Thomas KR Chien CB Losordo DW Li DY 《Science (New York, N.Y.)》2006,313(5787):640-644
Axonal guidance and vascular patterning share several guidance cues, including proteins in the netrin family. We demonstrate that netrins stimulate proliferation, migration, and tube formation of human endothelial cells in vitro and that this stimulation is independent of known netrin receptors. Suppression of netrin1a messenger RNA in zebrafish inhibits vascular sprouting, implying a proangiogenic role for netrins during vertebrate development. We also show that netrins accelerate neovascularization in an in vivo model of ischemia and that they reverse neuropathy and vasculopathy in a diabetic murine model. We propose that the attractive vascular and neural guidance functions of netrins offer a unique therapeutic potential. 相似文献
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Abramovici A Althouse WE Drever RW Gürsel Y Kawamura S Raab FJ Shoemaker D Sievers L Spero RE Thorne KS Vogt RE Weiss R Whitcomb SE Zucker ME 《Science (New York, N.Y.)》1992,256(5055):325-333
The goal of the Laser Interferometer Gravitational-Wave Observatory (LIGO) Project is to detect and study astrophysical gravitational waves and use data from them for research in physics and astronomy. LIGO will support studies concerning the nature and nonlinear dynamics of gravity, the structures of black holes, and the equation of state of nuclear matter. It will also measure the masses, birth rates, collisions, and distributions of black holes and neutron stars in the universe and probe the cores of supernovae and the very early universe. The technology for LIGO has been developed during the past 20 years. Construction will begin in 1992, and under the present schedule, LIGO's gravitational-wave searches will begin in 1998. 相似文献
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Cuttell L Corley SW Gray CP Vanderlinde PB Jackson LA Traub RJ 《Veterinary parasitology》2012,188(3-4):285-293
Trichinella nematodes are the causative agent of trichinellosis, a meat-borne zoonosis acquired by consuming undercooked, infected meat. Although most human infections are sourced from the domestic environment, the majority of Trichinella parasites circulate in the natural environment in carnivorous and scavenging wildlife. Surveillance using reliable and accurate diagnostic tools to detect Trichinella parasites in wildlife hosts is necessary to evaluate the prevalence and risk of transmission from wildlife to humans. Real-time PCR assays have previously been developed for the detection of European Trichinella species in commercial pork and wild fox muscle samples. We have expanded on the use of real-time PCR in Trichinella detection by developing an improved extraction method and SYBR green assay that detects all known Trichinella species in muscle samples from a greater variety of wildlife. We simulated low-level Trichinella infections in wild pig, fox, saltwater crocodile, wild cat and a native Australian marsupial using Trichinella pseudospiralis or Trichinella papuae ethanol-fixed larvae. Trichinella-specific primers targeted a conserved region of the small subunit of the ribosomal RNA and were tested for specificity against host and other parasite genomic DNAs. The analytical sensitivity of the assay was at least 100 fg using pure genomic T. pseudospiralis DNA serially diluted in water. The diagnostic sensitivity of the assay was evaluated by spiking 10 g of each host muscle with T. pseudospiralis or T. papuae larvae at representative infections of 1.0, 0.5 and 0.1 larvae per gram, and shown to detect larvae at the lowest infection rate. A field sample evaluation on naturally infected muscle samples of wild pigs and Tasmanian devils showed complete agreement with the EU reference artificial digestion method (k-value=1.00). Positive amplification of mouse tissue experimentally infected with T. spiralis indicated the assay could also be used on encapsulated species in situ. This real-time PCR assay offers an alternative highly specific and sensitive diagnostic method for use in Trichinella wildlife surveillance and could be adapted to wildlife hosts of any region. 相似文献
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Targeted biological therapies hold tremendous potential for treatment of cancer, yet their use has been limited by constraints on delivery and effective tumor targeting. We combined an immune effector cell population [cytokine-induced killer (CIK) cells] with an oncolytic viral therapy to achieve directed delivery to, and regression of, tumors in both immunodeficient and immunocompetent mouse models. Preinfection of CIK cells with modified vaccinia virus resulted in a prolonged eclipse phase with the virus remaining hidden until interaction with the tumor. Whole-body imaging revealed that the cells retained their ability to traffic to and to infiltrate the tumor effectively before releasing the virus. These results illustrate the potential of combining biotherapeutics for synergistic effects that more effectively treat cancer. 相似文献