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91.
Survey and contrast radiographic studies of the cardiovascular and gastrointestinal systems of the American horseshoe crab (Limulus polyphemus) were undertaken using conventional and flouroscopic techniques. Normal gastrointestinal and cardiovascular structures were difficult to resolve on survey radiographs, but were well visualized with gastrointestinal follow through studies and angiography, respectively. All three contrast agents (iohexol, Gastrografin, and barium sulfate) used for the gastrointestinal studies varied minimally in their radiographic quality and transit times, and all appeared to be safe for use in the horseshoe crab. 相似文献
92.
93.
甜瓜蔓枯病菌子实体法分离及A型菌株产孢条件研究 总被引:1,自引:0,他引:1
为解决甜瓜蔓枯病菌(Didymellabryoniae)组织分离法中枯萎病菌污染和单孢分离法操作复杂的问题,采用挑取单个子实体分离纯化获得甜瓜蔓枯病菌A型菌株。该菌株在12h荧光/12h黑暗的常规光照条件下,不能形成分生孢子器,但经过一定时间的暗处理和间歇紫外灯(12h紫外灯/12h黑暗)照射后则能够产生大量分生孢子。研究了光照、温度、pH值、培养基、碳源、氮源对产孢量的影响。综合各种因素,A型菌株产生分生孢子的最佳条件为:7d暗培养和4d间歇紫外灯处理的光照条件下,只含有磷酸二氢氨的马铃薯平板培养基,25℃时产生的分生孢子量最多。 相似文献
94.
Chu-Hui Chiang Chun-Yee Lee Ching-Hsien Wang Fuh-Jyh Jan Shih-Shun Lin Tsung-Chi Chen Joseph A. J. Raja Shyi-Dong Yeh 《European journal of plant pathology / European Foundation for Plant Pathology》2007,118(4):333-348
Papaya ringspot virus (PRSV) HA 5-1, a nitrous acid-induced mild mutant of severe strain HA, widely applied for control of PRSV by cross-protection,
was used to study the genetic basis of attenuation. Using infectious clones, a series of recombinants was generated between
HA 5-1 and HA and their infectivity was analyzed on the systemic host papaya and the local lesion host Chenopodium quinoa. The recombinants that contained mutations in P1 and HC-Pro genes caused attenuated infection on papaya without conspicuous
symptoms, similar to HA 5-1. The recombination and sequence analyses strongly implicated two amino acid changes in the C-terminal
region of P1 and two in HC-Pro of HA 5-1 involved in the attenuated infection on papaya. The recombinants that infected C. quinoa plants without local lesions contained the same mutations in the C-terminal region of HC-Pro for attenuated infection on
papaya. We conclude that both P1 and HC-Pro bear important pathogenicity determinants for the infection on the systemic host
papaya and that the mutations in HC-Pro affecting pathogenicity on papaya are also responsible for the inability to induce
hypersensitive reaction on C. quinoa. 相似文献
95.
Joseph Aubert Mouen Bedimo Daniel Bieysse Ibrahim Njiayouom Jean Pierre Deumeni Christian Cilas Jean Loup Nottéghem 《European journal of plant pathology / European Foundation for Plant Pathology》2007,119(4):391-400
In the high altitude regions of Africa, coffee berry disease (CBD), caused by Colletotrichum kahawae, is the main constraint for arabica coffee (Coffea arabica) production. However, certain agricultural practices can reduce losses caused by the disease and thereby promote optimum
production. On small family farms in Cameroon, mixed cropping with fruit trees, intercropping with food crops and maintenance
pruning of coffee trees are very widespread agricultural practices that can affect CBD epidemics. Consequently, an epidemiological
study was conducted to assess how cultural practices affected the disease in an arabica coffee smallholding in Cameroon. The
disease was monitored on a weekly basis over four successive years (2002–2005) on coffee trees in diverse cultural situations.
Cultural practices likely to reduce losses due to CBD were identified. The infection rate was significantly lower on coffee
trees grown intensively than on coffee trees grown in the traditional manner. Coffee trees located under the shade of fruit
trees were significantly less attacked than those located in full sunlight. In addition, berries on the leafless parts of
branches, near the main trunk of the coffee tree, were less infected than those on leafy sections. These results show that
maintenance pruning, removal of mummified berries, and mixed cropping with shade plants are cultural practices which create
environmental conditions that limit CBD development. 相似文献
96.
Although Synchytrium endobioticum has been found in almost all potato-growing countries of the EPPO region, it is absent from the great majority of fields. A few plots scattered across the potato-growing areas have been ‘scheduled’ as infested but potatoes are not grown on them. The disease is accordingly hardly ever seen. This is the result of continent-wide multiyear campaign of potato wart control within countries, according to which it is prohibited to grow potatoes on infested plots, and only resistant cultivars may be grown in a safety zone around them. S. endobioticum can persist for several decades in soil, as resting spores, but it is now dying out in plots that have been subject to the control campaign for a sufficiently long period. Procedures are now being agreed for officially ‘descheduling’ such plots. 相似文献
97.
ELIZABETH A. MAULDIN DANNY W. SCOTT WILLIAM H. MILLER & CHRISTINA A. SMITH 《Veterinary dermatology》1997,8(3):191-202
A retrospective histopathological and immunopathological study was conducted on 86 dogs with Malassezia dermatitis. West Highland White terriers, English Setters, Shih Tzus, Basset Hounds, American Cocker Spaniels, spayed females, and castrated males were found to be at increased risk. The histopathological reaction pattern of lymphocytic superficial perivascular to interstitial dermatitis with parakeratotic hyperkeratosis, irregular epidermal hyperplasia, diffuse intercellular oedema and lymphocytic exocytosis was found to be consistent with a diagnosis of Malassezia dermatitis whether yeast were histologically visible (73.3% of the cases) or not (26.7%). Immunopathological studies revealed that 60– > 90% of the inflammatory cells within the epidermis, and 25–75% of those within the dermis were CD3+T lymphocytes, and that the only immunoglobulin-positive cells were dermal plasma cells. 相似文献
98.
JOHN V. YOVICH BSc BVMS A. S. TURNER BVSc MS DiplomateACVS F. W. SMITH BSME MSME PhD 《Veterinary surgery : VS》1985,14(3):230-234
Comparison was made of the holding power of 5.5 and 4.5 mm cortical orthopedic screws inserted into third metacarpal and metatarsal cadaver bones from 3- and 8-year-old horses. The tensile strength of these screws was tested mechanically. In nine comparative trials of these screws, 5.5 mm screws pulled out of bone in five trials at an average of 116.0 kg tensile force and broke in four trials at an average of 1383.2 kg. A 4.5 mm screw pulled out of bone at 834.5 kg in one trial, and screws broke at an average of 849.2 kg in eight trials. The larger 5.5 mm screw required a significantly greater (p = 0.022) pullout force than the mean force at 4.5 mm screw breakage. Fixation failure was due to screw breakage or bone shear, with 5.5 mm screws occasionally creating bone fragmentation during pullout. The average tensile breaking strengths of the 5.5 mm screws (1391.4 kg) and 4.5 mm screws (832.7 kg) determined mechanically were similar to forces at screw breakage during pullout testing in bone. Since the 5.5 mm screws have greater holding power and tensile strength than 4.5 mm screws, the use of the 5.5 mm screw in fracture repair in adult horses is recommended. 相似文献
99.
Medial Plating for the Repair of Middle and Distal Diaphyseal Fractures of the Humerus in Dogs 总被引:1,自引:0,他引:1
JOSEPH HARARI ms dvm SIMON C. ROE bvsc mvst ANN L. JOHNSON dvm ms Dipiomateacvs CHARLES W. SMITH dvm ms Dipiomateacvs 《Veterinary surgery : VS》1986,15(1):45-48
Six middle and distal humeral shaft fractures in dogs were repaired by the application of a bone plate along the medial shaft of the humerus. In all animals, clinical and radiographic evidence of normal bone healing was observed. The bone plate and ancillary implants were removed from five dogs by 10 months. In none of the six dogs were any untoward effects of placing the bone plate along the medial shaft of the humerus detected nor were there any difficulties encountered with the medial humeral soft tissues. 相似文献
100.