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81.
Davis ST Benson BG Bramson HN Chapman DE Dickerson SH Dold KM Eberwein DJ Edelstein M Frye SV Gampe RT Grifffen RJ Harris PA Hassell AM Holmes WD Hunter RN Knick VB Lackey K Lovejoy B Luzzio MJ Murray D Parker P Rocque WJ Shewchuk-Chapman L Veal JM Walker DH Kuyper LF 《Science (New York, N.Y.)》2002,298(5602):2327
82.
The three-dimensional structure of canine parvovirus and its functional implications 总被引:59,自引:0,他引:59
J Tsao M S Chapman M Agbandje W Keller K Smith H Wu M Luo T J Smith M G Rossmann R W Compans 《Science (New York, N.Y.)》1991,251(5000):1456-1464
The three-dimensional atomic structure of a single-stranded DNA virus has been determined. Infectious virions of canine parvovirus contain 60 protein subunits that are predominantly VP-2. The central structural motif of VP-2 has the same topology (an eight-stranded antiparallel beta barrel) as has been found in many other icosahedral viruses but represents only about one-third of the capsid protein. There is a 22 angstrom (A) long protrusion on the threefold axes, a 15 A deep canyon circulating about each of the five cylindrical structures at the fivefold axes, and a 15 A deep depression at the twofold axes. By analogy with rhinoviruses, the canyon may be the site of receptor attachment. Residues related to the antigenic properties of the virus are found on the threefold protrusions. Some of the amino termini of VP-2 run to the exterior in full but not empty virions, which is consistent with the observation that some VP-2 polypeptides in full particles can be cleaved by trypsin. Eleven nucleotides are seen in each of 60 symmetry-related pockets on the interior surface of the capsid and together account for 13 percent of the genome. 相似文献
83.
FREDRIK E. HOPPE DVM PHD DAVE A. HAGER DVM PAUL W. POULOS JR. DVM PHD STINA EKMAN DVM P. G. LINDGREN MD PHD 《Veterinary radiology & ultrasound》1986,27(4):99-101
A manual, ultrasound-guided biopsy technique was compared to a new automatic method using a new biopsy device. The liver and the left kidney of 10 dogs were biopsied using the two methods. The specimens from the biopsies were compared for size and quality. Results demonstrate that larger and higher quality samples were obtained with the new automatic method. 相似文献
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M. S. Chapman M. H. Lucas C. N. Hebert R. G. Goodey 《Veterinary research communications》1979,3(1):137-139
No loss in the titre of infectious bovine rhinotracheitis virus was found during storage in semen at –196°C for 1 year. 相似文献
88.
Adult wild-trapped opossums were infected with Leishmania donovani (Khartoum strain, WR 378) and evaluated as an animal model of visceral leishmaniasis. All infected opossums died within 32 days. Loss of body fat, hepatomegaly, and petechiae of skin and abdominal musculature were seen at necropsy. Microscopically, numerous amastigote-laden macrophages were seen in histologic sections of liver, spleen, and lymph nodes; fewer parasite-laden macrophages were in the bronchial-associated lymphoid tissues and renal glomeruli. Hematological findings included thrombocytopenia (terminal), neutropenia, and lymphopenia. Blood lymphocyte blastogenesis in response to concanavalin A and phytohemagglutinin was decreased markedly at day 24 post-infection (PI). Serum antibodies (1:40 dilution) to promastigotes of L. donovani were detected in five of eight infected opossums tested on days 10 and 24 PI. Total bilirubin concentrations and alanine aminotransferase and aspartate aminotransferase activities were increased after day 25 PI. Activated partial thromboplastin times and one-stage prothrombin times were prolonged before death. Concurrently, factors V, VIII, and XII activities were decreased. 相似文献
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