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31.
A synthetic complex of poly (I)-poly (C) with poly-L-lysine and carboxymethyl cellulose (poly ICLC), as well as UV-inactivated Newcastle disease virus, B-1 strain, was used to induce interferon production in dogs. Several criteria were used for interferon specificity. The interferon response depended on dosage and route of inoculation. Serum interferon concentrations usually reached a peak by 8 hours after inoculation (AI), rapidly declined thereafter, and were nondetectable in most instances at 24 hours AI. Dogs responded less to interferon inducers when reinoculated 2 days after primary induction. The interferon response was biphasic (2 and 8 hours AI) when reinoculated 1 week after primary inoculation. Reinoculation 2 weeks after primary inoculation simulated the first response. Although both inducers caused severe lymphopenia in dogs, the toxic side effects would limit clinical use (in dogs) of poly ICLC, but not of UV-inactivated Newcastle disease virus. 相似文献
32.
Leptospirosis in the Philippines: canine studies 总被引:1,自引:0,他引:1
33.
Amantadine: neuromuscular blockade by suppression of ionic conductance of the acetylcholine receptor 总被引:5,自引:0,他引:5
E X Albuquerque A T Eldefrawi M E Eldefrawi N A Mansour M C Tsai 《Science (New York, N.Y.)》1978,199(4330):788-790
Amantadine hydrochloride decreases the sensitivity of denervated mammalian muscle to iontophoretically applied acetylcholine. The drug depresses the amplitude of the end-plate current and reverses the slope of the relation between half-decay time and membrane potential suggesting that it alters the ionic conductance that is mediated by the acetylcholine receptor. Binding studies confirm that amantadine acts on the ion conductance modulator rather than the acetylcholine receptor. 相似文献
34.
Heading Chinese cabbage (Brassica campestris ssp. pekinensis Rupr.) grown with low Ca or B developed dark tan lesions near the leaf margins. A synergistic effect of low Ca and low B accompanied the development of this symptom. Plants grown under humid conditions were free of tipburn. Plants grown under less humidity developed tipburn. Total chemical analysis revealed a steady decrease in total Ca from the outer to the inner leaves. Fractional chemical analysis showed 7 times more water-soluble Ca in the outer than in the inner leaves, and 2 times more 1 N NaCl-soluble Ca in the outer than in inner leaves. Threshold concentration of water-soluble forms of Ca for tipburn was around 3.0 mg/g dry weight. Data suggest that root pressure flow is required to move adequate amounts of water-soluble Ca to the wrapper leaves to prevent tipburn of Chinese cabbage. 相似文献
35.
Bedenice D Bar-Yishay E Ingenito EP Tsai L Mazan MR Hoffman AM 《American journal of veterinary research》2004,65(9):1259-1264
OBJECTIVE: To evaluate the use of a modified whole body plethysmograph in awake sheep. ANIMALS: 10 healthy adult sheep. PROCEDURE: Concurrent measurements of specific airway resistance (sR(aw)) and pulmonary resistance (R(L)) were obtained using a novel noninvasive head-out constant-volume plethysmograph and esophageal balloon-pneumotachography, respectively. All data were collected before and after external resistive loading with 1 and 5.6 cm H2O/L/s. Functional residual capacity (FRC) was measured by helium dilution for computation of airway resistance (R(aw)) preloading (R(aw) = sR(aw)/FRC). RESULTS: The sR(aw) and R(L) were closely correlated in 10 adult sheep. Additionally, sR(aw), and R(L) accurately reflected the magnitude of added resistance. The mean FRC was 52 mL/kg and used to calculate R(aw). At baseline, the values for R(aw) were significantly correlated with sR(aw) and R(L). CONCLUSIONS AND CLINICAL RELEVANCE: Precise measurements of sR(aw) and R(aw) at baseline and sR(aw) after external resistive loading were obtained by use of this novel noninvasive plethysmographic technology. This method should have application to veterinary patients or animals used in research in which noninvasive rapid or serial measurements of sR(aw) in the conscious state are required. 相似文献
36.
Forouhar AS Liebling M Hickerson A Nasiraei-Moghaddam A Tsai HJ Hove JR Fraser SE Dickinson ME Gharib M 《Science (New York, N.Y.)》2006,312(5774):751-753
The embryonic vertebrate heart begins pumping blood long before the development of discernable chambers and valves. At these early stages, the heart tube has been described as a peristaltic pump. Recent advances in confocal laser scanning microscopy and four-dimensional visualization have warranted another look at early cardiac structure and function. We examined the movement of cells in the embryonic zebrafish heart tube and the flow of blood through the heart and obtained results that contradict peristalsis as a pumping mechanism in the embryonic heart. We propose a more likely explanation of early cardiac dynamics in which the pumping action results from suction due to elastic wave propagation in the heart tube. 相似文献
37.
Forty Ornithobacterium rhinotracheale (ORT) strains were isolated from 28 chickens and 12 pigeons for the first time in Taiwan. All isolates reacted positively in the p-nitrophenyl-beta-D-galactopyranoside (PNPG) and oxidase tests, showing an API 20NE identification system biocode 0-0-2-0-0-0-4. All the pigeon isolates and 85.7% (24 of 28) of the chicken isolates belonged to serotype A. Compared to the ORT ATCC 51464 strain, 14.3% (4 of 28) of chicken isolates and 58.3% (7 of 12) of pigeon isolates showed smaller colonies after 72 hr incubation. Most of the chicken isolates (22 of 28), but none of the pigeon isolates, could agglutinate chicken and pigeon red blood cells. There appears to be a correlation that ORT isolates with a larger colony size tend to be more able to agglutinate red blood cells than the ORT isolates with a smaller colony size. A majority of isolates was sensitive to amoxicillin, ampicillin, ceftiofur, penicillin, and oxytetracycline. The 16S ribosomal RNA (rRNA) sequences of 23 Taiwanese ORT isolates showed high identity (98%-100%) to sequences in GenBank. Phylogenetic analysis of these sequences showed that pigeon isolates formed a distinctive cluster, while chicken isolates and all other 16S rRNA sequences obtained from GenBank belonged to another two clusters. The results indicate that pigeon ORT isolates are different from most chicken isolates in regard to a number of phenotypic and molecular traits. 相似文献
38.
Seismological observations of the 2012 moment magnitude 8.6 Sumatra earthquake reveal unprecedented complexity of dynamic rupture. The surprisingly large magnitude results from the combination of deep extent, high stress drop, and rupture of multiple faults. Back-projection source imaging indicates that the rupture occurred on distinct planes in an orthogonal conjugate fault system, with relatively slow rupture speed. The east-southeast-west-northwest ruptures add a new dimension to the seismotectonics of the Wharton Basin, which was previously thought to be controlled by north-south strike-slip faulting. The rupture turned twice into the compressive quadrant, against the preferred branching direction predicted by dynamic Coulomb stress calculations. Orthogonal faulting and compressional branching indicate that rupture was controlled by a pressure-insensitive strength of the deep oceanic lithosphere. 相似文献
39.
Tsang L Lin Chien C Loa Shih C Tsai Ching C Wu Tom A Bryan H Leon Thacker Tom Hooper Donna Schrader 《Veterinary microbiology》2002,84(1-2):179-186
The present study was to characterize turkey coronavirus associated with turkey poult enteritis and mortality. Intestinal contents or intestines from affected turkey poults and inoculated turkey embryos contained coronaviruses as revealed by electron microscopy or were positive for turkey coronavirus by immunofluorescent antibody assay. Sucrose density gradient ultracentrifugation of the virus-containing intestinal homogenate yielded two opalescent bands corresponding to the buoyant densities of 1.14-1.15 and 1.18-1.20 g/ml, respectively. Coronaviral particles from intestinal contents or the sucrose density gradient preparation were mainly spherical in shape and had envelope and central depression. They were surrounded by a fringe of regularly spaced petal-shaped projections attached to the particles by a short stalk. Purified viruses hemagglutinated rabbit erythrocytes with a titer of 16. Major protein bands of purified viruses analyzed by SDS-PAGE were located at 200, 100-110, 50-60, and 30-35 kDa. The patterns of protein bands were consistent with those of Minnesota or Quebec turkey coronavirus isolates. A 568 bp nucleotide fragment of turkey coronavirus spike protein gene was amplified from RNA of inoculated turkey embryo intestine or purified virus. Sequence analysis of the 568 bp PCR product revealed high degree of identity with the corresponding spike protein gene sequence of human and bovine coronaviruses. The results indicated that turkey coronavirus was associated with turkey poults with acute enteritis. 相似文献
40.
P. Kadirvel R. de la Peña R. Schafleitner S. Huang S. Geethanjali L. Kenyon W. Tsai P. Hanson 《Euphytica》2013,190(2):297-308
Tomato (yellow) leaf curl disease (TYLCD) is a serious threat to tomato production in the tropics and subtropics. The genetics of resistance to Tomato yellow leaf curl Thailand virus Taiwan strain (TYLCTHV-[TW]) in a highly resistant tomato line FLA456 was studied through quantitative trait loci (QTL) analysis. Four QTLs named qTy4.1, qTy6.1, qTy10.1 and qTy11.1 were detected on chromosomes 4, 6, 10, and 11, respectively, through evaluation of an F6 recombinant inbred line (RIL) population derived from a cross between FLA456 (resistant) and CLN1621L (susceptible). Gene action of all QTLs was recessive based on disease reaction of the F1. The markers SINAC1 and SLM4-34 flanked qTy4.1 on chromosome 4, and SLM11-12 and SLM11-17 defined qTy11.1, which co-located with the previously identified Ty-5 and Ty-2 loci, respectively. qTy6.1 was flanked by the markers SLM6-55 and TES-0014, and qTy10.1 by the markers SLM10-80-SLM10-46 on chromosomes 6 and 10. The LOD values of the putative QTLs ranged from 2.79 to 13.76. The phenotypic variance explained by each QTL ranged from 7.1 to 31.9 %. The four QTLs collectively contributed about 60.5 % of the phenotypic variation in resistance against TYLCTHV-[TW]. Group mean severity scores of those RILs possessing three or four qTy were generally lower than RIL groups with only one or no qTy. Given the diversity of begomoviruses that cause TYLCD across the regions, the new QTLs from FLA456 would be valuable in tomato breeding for developing varieties with durable resistance. Two QTL intervals (qTy4.1 and qTy10.1) contained virus resistance candidate genes such as CTV.22 and eukaryotic translation initiation factor 4E. 相似文献