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171.
D D Bowman D S Lin R C Johnson R C Lynn D I Hepler D G Stansfield 《American journal of veterinary research》1991,52(9):1542-1544
Twenty-four specific-pathogen-free Beagles were each given 50 cysticerci of Taenia pisiformis that had been harvested from experimentally infected rabbits. Quantitative fecal egg counts and fecal screening for recovery of passed segments were performed on postinoculation days 56 through 70. Twenty-three of 24 dogs fed cysticerci developed patent infections. The 23 dogs with patent infections were assigned to 1 of 2 groups and treated with nitroscanate or a placebo 60 days after inoculation. Egg counts in the treated dogs had markedly decreased by the second day after treatment, and by the sixth day after treatment, segments were not found in the feces of any of the treated animals. The control dogs continued to pass eggs and segments in their feces throughout the 9 days after treatment. The dogs were euthanatized and necropsied 70 days after being inoculated. At necropsy, the mean number of scolices recovered from control dogs was 24.6, the mean number of scolices recovered from treated dogs was 0.25. Worms recovered from the control dogs were intact, gravid cestodes. Efficacy of treatment with nitroscanate at a mean dosage of 56 mg/kg of body weight was 98.9%. 相似文献
172.
Richard F. Keeler Lynn F. James Wayne Binns James L. Shupe 《Canadian journal of veterinary research》1967,31(12):334-341
An apparent relationship between locoism and lathyrism was investigated. Similarities reported in the literature in botanical relationship, signs produced in affected animals, and chemical characteristics were noted. It was demonstrated that the known lathyrogens, aminoacetonitrile and α, γ-diaminobutyric acid, as well as an extract from the loco plant (expected to contain lathyrogens if present in the plant) produced many of the abortive, teratogenic and neurologic effects and signs evident in animals in true locoism. Preliminary assay of extracts from the plant suggested the presence of lathyrogens in the loco plant. 相似文献
173.
174.
Annalisa Polverari Roberto Buonaurio Samantha Guiderdone Mario Pezzotti Mario Marte 《European journal of plant pathology / European Foundation for Plant Pathology》2000,106(5):423-431
Ultrastructural details of the hypersensitive reaction induced by infiltration with avirulent race 2 Xanthomonas campestris pv. vesicatoria in pepper Early Calwonder-10R leaves (incompatible interaction) are reported. Affected cells displayed plasmalemma undulations and disruption, lysis of the chloroplast membrane, degeneration of other organelles, general cytoplasm disorganisation and, often, protoplast shrinkage. The nuclei contained large masses of electron-dense material, apparently formed by chromatin aggregation. In many cases a single chromatin-like layer was deposited on the inner side of the nuclear envelope leaving a finely granular matrix in the centre of the nucleus; the nucleolus usually disappeared. The nuclear envelope was sometimes ruptured and the internal matrix leaked into the cytoplasm. The content of many affected cells eventually coagulated and became very electron-dense. The walls often collapsed. All these alterations were especially visible in spongy mesophyll cells at sites where bacteria occurred in the intercellular spaces. Although some of the nuclear and cytoplasmic alterations recall certain aspects of apoptotic cell death, molecular determinations did not reveal any DNA degradation in hypersensitively reacting tissues. The first cell alterations in leaves infected with the virulent bacterial race 1 (compatible interaction) were observed only 27h after inoculation, when the cytoplasm of some cells showed limited internal disorganisation and plasmolysis at sites where bacterial colonies developed. 相似文献
175.
18F‐Fluoro‐deoxyglucose positron emission computed tomography (FDG‐PET/CT) is an emerging diagnostic imaging modality in veterinary medicine; however, little published information is available on physiologic variants, benign processes, and artifacts. The purpose of this retrospective study was to describe the number of occurrences of non‐neoplastic disease‐related FDG‐PET/CT lesions in a group of dogs and cats. Archived FDG‐PET/CT scans were retrieved and interpreted based on a consensus opinion of two board‐certified veterinary radiologists. Non‐neoplastic disease‐related lesions were categorized as physiologic variant, benign activity, or equipment/technology related artifact. If the exact cause of hypermetabolic areas could not be determined, lesions were put into an indeterminate category. A total of 106 canine and feline FDG‐PET/CT scans were included in the study. In 104 of the 106 scans, a total of 718 occurrences of physiologic variant, areas of incidental benign activity, and artifacts were identified. Twenty‐two of 23 feline scans and 82 of 83 canine scans had at least one artifact. Previously unreported areas of increased radiopharmaceutical uptake included foci associated with the canine gall bladder, linear uptake along the canine mandible, and focal uptake in the gastrointestinal tract. Benign activity was often seen and related to healing, inflammation, and indwelling implants. Artifacts were most often related to injection or misregistration. Further experience in recognizing the common veterinary FDG physiologic variation, incidental radiopharmaceutical uptake, and artifacts is important to avoid misinterpretation and false‐positive diagnoses. 相似文献
176.
Reduced insulin-like signaling extends the life span of Caenorhabditis elegans and Drosophila. Here, we show that, in mice, less insulin receptor substrate-2 (Irs2) signaling throughout the body or just in the brain extended life span up to 18%. At 22 months of age, brain-specific Irs2 knockout mice were overweight, hyperinsulinemic, and glucose intolerant; however, compared with control mice, they were more active and displayed greater glucose oxidation, and during meals they displayed stable superoxide dismutase-2 concentrations in the hypothalamus. Thus, less Irs2 signaling in aging brains can promote healthy metabolism, attenuate meal-induced oxidative stress, and extend the life span of overweight and insulin-resistant mice. 相似文献
177.
Winn MP Conlon PJ Lynn KL Farrington MK Creazzo T Hawkins AF Daskalakis N Kwan SY Ebersviller S Burchette JL Pericak-Vance MA Howell DN Vance JM Rosenberg PB 《Science (New York, N.Y.)》2005,308(5729):1801-1804
Focal and segmental glomerulosclerosis (FSGS) is a kidney disorder of unknown etiology, and up to 20% of patients on dialysis have been diagnosed with it. Here we show that a large family with hereditary FSGS carries a missense mutation in the TRPC6 gene on chromosome 11q, encoding the ion-channel protein transient receptor potential cation channel 6 (TRPC6). The proline-to-glutamine substitution at position 112, which occurs in a highly conserved region of the protein, enhances TRPC6-mediated calcium signals in response to agonists such as angiotensin II and appears to alter the intracellular distribution of TRPC6 protein. Previous work has emphasized the importance of cytoskeletal and structural proteins in proteinuric kidney diseases. Our findings suggest an alternative mechanism for the pathogenesis of glomerular disease. 相似文献
178.
Lynn L 《Science (New York, N.Y.)》1986,233(4761):296-301
Until recently the Japanese did not spend much on research and what they did spend was concentrated on the commercial development of technology. As a result there have so far been few Japanese breakthroughs in either science or technology. Dramatic changes have recently occurred, however, and Japan now trails only the United States and the Soviet Union in research spending. Beyond this, Japanese policy-makers are making a determined effort to overcome Japan's social and institutional barriers to scientific creativity. 相似文献
179.
180.
Hackett KJ Lynn DE Williamson DL Ginsberg AS Whitcomb RF 《Science (New York, N.Y.)》1986,232(4755):1253-1255
Uncultivable for more than 25 years, the sex-ratio spiroplasma of Drosophila willistoni grew in a tissue culture medium (H-2) containing an embryo-derived lepidopteran cell line (IPLB-TN-R(2)). After adaptation, it grew in a cell-free H-2 medium. This success demonstrates the usefulness of cell culture systems for cultivation of fastidious microorganisms and facilitates study of the sex-ratio trait in Drosophila. 相似文献