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51.
Reasons for performing study: Identification of the species and strain of dermatophyte can play an effective role in control of disease outbreaks by establishing the source of infection. Current methods of identification are based on cultural and microscopic methods, often involving weeks before a positive identification are made. A rapid molecular diagnostic method would therefore be an important laboratory technique, but requires confirmation in equine clinical practice. Objectives: To test the sensitivity and specificity of molecular diagnostic methods applied to a racehorse herd from the Korean Racehorse Authority (KRA). Methods: A total of 57 DNA samples were collected from hairs and crusts of skin lesions in KRA racehorses with histories and clinical signs suggestive of dermatophytosis, which was confirmed by dermatophyte‐specific PCR amplification analysis using the primer pair for the chitin synthase 1 (CHS1) gene. Results: Thirty‐eight racehorses were definitively diagnosed with dermatophytosis using molecular and traditional diagnostic methods. PCR fingerprinting profiles using simple repetitive (GACA)4 primers showed that all diagnosed horses had the same pattern profile. Oligonucleotide sequencing of CHS1 gene PCR products confirmed Trichophyton mentagrophytes as the infectious agent. Conclusions: This study demonstrates that the PCR‐based molecular diagnostic method is sensitive and specific and offers fast precise diagnosis of dermatophytosis in horses.  相似文献   
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叶片表皮指纹在杜鹃花属分类中的意义   总被引:5,自引:0,他引:5  
本实验于2004年在东北林业大学进行。用指甲油印记法在光学显微镜下观察了杜鹃花属6个种(牛皮杜鹃 Rh.aureaum,兴安杜鹃Rh. dauricum, 照白杜鹃Rh. micranthum,迎红杜鹃Rh. mucronulatum,苞叶杜鹃 Rh. Redowskianum 和大字杜鹃Rh. schlippenbachii)的表皮指纹特征。对叶片的形态特征包括叶片下表皮气孔类型、保卫细胞和副卫细胞的特征、叶片两面的普通细胞(形状和垂周壁特征)和表皮毛进行了较详细的描述。所研究的6种杜鹃花中,有3种气孔类型,其中兴安杜鹃、照白杜鹃、和迎红杜鹃为单细胞型气孔(Pericytic 型),苞叶杜鹃为不规则型气孔(Anomocytic 型),牛皮杜鹃和大字杜鹃是平轴式气孔(Diacytic 式)。不同种间,单细胞型和平轴式气孔的副卫细胞类型在形状和表面特征上有所不同。普通表皮细胞的表面观为从四边形、六边形, 多边形或不规则型, 垂周壁呈平直或弯曲状。兴安杜鹃、照白杜鹃和迎红杜鹃3种的叶片两面均有腺鳞。所有这些叶片特点表明上述6种杜鹃花的表皮指纹具有种的特性。图4表2参29。  相似文献   
54.
This fluorescence and immunoelectron microscopic study showed that β-1,3-D-glucan accumulated only in leaves of a susceptible cultivar of Japanese pear after treatment with a host-specific toxin, AK-toxin I, from Alternate, alternata Japanese pear pathotype. The positive fluorescent reaction of callose was detected only in aniline blue fluorochrome-stained sections from toxin-treated leaves of the susceptible cultivar: positive sites were observed on cell walls of leaf cells. The sites of callose deposition were probably consistent spatially with modified sites on the plasma membrane that were observed only in the toxin-treated leaves of the susceptible cultivar. The toxin-induced modifications, identified as damage to the plasma membrane, were characterized by invagination of the plasmalemma specifically at plasmodesmata and as the concomitant accumulation of extracellular polysaccharides at the invaginated sites. A positive reaction to anti-β-1,3-D-glucan antibody was detected at the polysaccharides, Golgi vesicles, and trans-Golgi network (TGN) of toxin-treated leaves of the susceptible cultivar, but not at Golgi vesicles and TGN of water-treated ones. The cis-, medial and trans-Golgi stacks of toxin-treated leaves of the susceptible cultivar were negative for the antibody. The results showed that the polysaccharides, Golgi vesicles and TGN contained abundant β-1,3-D-glucan and that the glucan was transported from the Golgi apparatus via Golgi vesicles to the modified sites in cells of toxin-treated leaves of the susceptible cultivar. Received 7 March 2002/ Accepted in revised form 10 June 2002  相似文献   
55.
梨黑星病是亚洲梨的主要病害之一。该病是由纳雪黑星病菌(Venturia nashicola)感染所致。V.nashicola主要寄生在亚洲梨叶片表皮细胞壁的果胶质层中。该菌的感染可能主要与分泌的细胞外分泌物质、角质分解酶、过氧化氢和果胶质分解酶有关。而亚洲梨对V.nashicola的抗性可能主要与多聚半乳糖醛酸酶抑制蛋白、多种病程相关蛋白、富亮氨酸重复类受体蛋白激酶等有关。另外,不具直接杀菌能力的系统抗性诱导剂acibenzolar-S-methyl(ASM)在大田试验中对梨黑星病菌有较好控制效果。这与ASM诱导的植物防御反应,包括多聚半乳糖醛酸酶抑制蛋白和几丁质酶等有关。  相似文献   
56.
Medial patellar desmotomy was performed on one (treated) hindlimb, and a sham operation on the other (control) hindlimb, of 12 normal horses. The horses were examined for lameness before medial patellar desmotomy and at months 1, 2, and 3. The femoropatellar joints were examined radiographically and arthroscopically at month 3. All horses were lame on the treated limb at months 1, 2, or 3. Radiographic changes, including fragment formation at the distal aspect of the patella and bone production at the attachment of the middle patellar ligament on the patella, were present in 11 horses at month 3. Articular cartilage fibrillation or detachment was seen arthroscopically on the patellas of all treated limbs. In six horses, loosely attached fragments of bone and cartilage were removed arthroscopically from the distal aspect of the patella of the treated limb. The control limbs were clinically, radiographically, and arthroscopically normal throughout the study. Medial patellar desmotomy results in pathologic changes in the articular cartilage of the patella and adjacent soft tissues. Use of this surgical procedure should be reserved for persistent and confirmed cases of upward fixation of the patella.  相似文献   
57.
This study focuses upon changes in three computer-related industries between 1974 and 1985. An attempt is made by means of entropy indices and shift-share analysis to determine if diffusion in those industries conforms to the product-cycle model. We employ primarily state-level data derived from County Business Patterns and supplemented by US. Censuses of Manufacturing and Services. Our findings indicate that all the industries displayed substantial increases in employment and considerable dispersion, although by no means were the changes uniform. The hypothesis that the dispersion is following the product-cycle model, that is, from core areas to peripheral regions, receives little support from this study. The model, however, should not be rejected out of hand, because all three industries studied have a duality in the size of firms that the data masks. This duality may affect the applicability of any model. Further attempts to explain the spatial distribution of any of these industries should begin with disintegrated data. Unfortunately such data are not presently easily attainable.  相似文献   
58.
Fifteen clinical cases of gunshot fractures were studied. A radiographic classification of the fractures was developed to aid in fracture evaluation. Type I fractures involved a simple transverse or oblique fracture with minimal soft tissue damage. Type II fractures were severely comminuted with no cortical bone defect and minimal soft tissue damage. Type III fractures were "shatter" fractures, characterized by severe comminution, cortical bone defects, and extensive soft tissue damage. Type I and Type II fractures (combined 26.7%) healed in 8 weeks or less. Eleven of the 15 cases evaluated (73.3%) were found to be Type III fractures, requiring more than 14 weeks for complete cortical healing. Osteomyelitis was associated with 3 cases of Type III tibial fractures, 2 of which developed after a second surgical intervention. Management, complications, and prognosis of gunshot fractures are discussed.  相似文献   
59.
Virtual otoscopy enables noninvasive 3D endoluminal imaging of the middle ear through postprocessing of computed tompgraphy (CT) data. A standardized imaging approach for the middle ear was established in six normal dogs in an attempt to optimize the clinical application and student education. High‐resolution CT data were obtained. Virtual otoscopic images of the middle ear cavity and ossicles were generated using commercially available software. The views of the four different directions (the ear canal, tympanic bulla, eustachian tube, and ossicular chain) were made for virtual otoscopy. The promontory, cochlea window, tympanic bulla, septum bulla, and auditory tube were distinguished easily and clearly. One of the ossicles, the malleus, was visualized accurately. However, small structures such as the incus and stapes always could not be seen. The main advantage of virtual otoscopy is not only to provide diagnostic information but also to enhance the quality and efficiency of student education, because it contributes to an understanding of the anatomy of the middle ear. We describe the normal topographical 3Dimages of the middle ear of the dog using virtual otoscopy.  相似文献   
60.
The objective of the present study was to investigate the effects on the plasma biochemical composition and growth of piglets of placenta‐fed sows. The experimental animals were a total of 21 sows (L × LW) of third parity, and each sow was suckled by 11 ± 1 piglets. Sows fed without placenta were considered as the control (C), treatment 1 (T1) were placenta‐fed from days 1–7 after farrowing and treatment 2 (T2) were placenta‐fed from day 7 before farrowing to day 7 after farrowing. Glucose of piglets was lower (P < 0.05) in T2 than C and T1 on day 10. Total cholesterol of piglets was higher (P < 0.05) in T2 than C on day 4. Fe of piglets was higher (P < 0.05) in T2 than C on days 4, 20 and 30. Unsaturated iron‐binding capacity was lower (P < 0.05) in T2 than C on days 4 and 30. Immunoglobulin G of piglets was higher (P < 0.05) in T1 and T2 than C on days 4 and 10. Daily gain of piglets was higher (P < 0.05) in T1 than C and T2 on day 4 when daily gain was calculated. Total daily gain increased (P < 0.05) by prolongation of placenta feeding period. The results indicate that feeding placenta to sows may improve the plasma biochemical composition and growth of their piglets.  相似文献   
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