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11.
Susan J. Holcombe VMD MS Alicia L. Bertone DVM PhD David S. Biller DVM Valerie Haider DVM 《Veterinary radiology & ultrasound》1995,36(2):119-125
The purpose of this study was to define normal gross anatomic structures in the equine stifle with magnetic resonance images. Magnetic resonance (MR) images were made in sagittal, 15° supinated, transverse, and dorsal planes of two equine stifles. The MR images were scrutinized by comparing MR images to dissection specimens and frozen cross sections of stifle joints. Sagittal and 15° supinated images were the most valuable in assessing articular cartilage, subchondral bone, and soft tissue structures within the joint. Cranial and caudal cruciate ligaments, medial and lateral menisci, meniscotibial and meniscofemoral ligaments, long digital extensor tendon, and patellar ligaments were easily evaluated. MR images provided substantially more gross anatomical information than the currently available imaging modalities. 相似文献
12.
贮藏期间福桔果皮细胞始终具有分裂增殖能力,细胞生长的养分主要通过维管束向果肉吸取,因而促进果肉衰老,形成枯水.枯水果实在贮藏早期就发现果皮细胞层和油腔分泌细胞无丝分裂旺盛,双核细胞多,果皮增厚多.严重枯水时,果皮细胞还具细胞核、线粒体、有色体等超微结构,未枯水果实细胞分裂少见.经预贮后贮藏的果实,由于中断了果皮组织与维管束的联系,果皮细胞生长受抑制,果肉水分、养分消耗少,枯水率最低, 相似文献
13.
J. Rashid D. J. Weiss S. K. Maheswaran M. P. Murtaugh 《Veterinary research communications》1996,20(6):519-531
Local and systemic activation of coagulation is frequently associated with bacterial sepsis. The coagulopathy is due, at least in part, to expression of tissue factor (TF) by monocytes and macrophages. The purpose of this study was to evaluate the expression of procoagulant activity by bovine alveolar macrophages, leukocytes and platelets, and to determine the relative potency of three chemical inhibitors of TF expression (pentoxifylline, retinoic acid, and cyclosporin A). Bovine alveolar macrophages were stimulated with lipopolysaccharide (LPS) derived from Pasteurella haemolytica or recombinant bovine tumour nervous factor (TNF) and dose- and time-dependent effects on TF expression were studied. LPS and TNF induced TF expression in alveolar macrophages and LPS treatment of whole blood induced TF expression in mononuclear cells. Neutrophils and platelets also expressed procoagulant activity, but this activity was not inhibited by anti-bovine TF monoclonal antibody. Pentoxifylline (40 mol/L), retinoic acid (0.01 mmol/L) and cyclosporin A (0.08 mol/L) inhibited TF expression when added concurrently with LPS or TNF, but not when added 4 h after stimulation. TF mRNA was not detected in unstimulated alveolar macrophages by Northern blot analysis. In contrast, exposure to LPS or TNF for 6 h induced marked expression of TF mRNA, which was inhibited by treatment with pentoxifylline, retinoic acid and cyclosporin A. Expression of TNF by alveolar macrophages stimulated with LPS was also inhibited by these compounds. Our results indicate that procoagulant activity expressed by alveolar macrophages and monocytes is associated with expression of TF, whereas procoagulant activity expressed by neutrophils and platelets is not. The concentrations of pentoxifylline and retinoic acid necessary for inhibition of TF expression in vitro may not be achievable in vivo owing to their toxic effects. However, the in vitro concentration of cyclosporin A that inhibited TF expression did not exceed the plasma concentration observed in humans, and therefore may be useful for inhibition of TF expression in vivo.Abbreviations BAL
bronchoalveolar lavage
- LPS
lipopolysaccharide
- cDNA
cloned deoxyribonucleic acid
- cAMP
cyclic adenosine monophosphate
- GAPDH
glyceraldehyde phosphate dehydrogenase
- mRNA
messenger ribonucleic acid
- TF
tissue factor
- TNF
tumour necrosis factor
- DPBS
Dulbecco's phosphate-buffered saline 相似文献
14.
红千层的离体培养及快速繁殖 总被引:3,自引:0,他引:3
研究了红千层离体快繁的若干影响因素。结果表明: 叶片在MS + 6-BA 115 mg·L - 1+NAA015 mg·L - 1中的愈伤组织诱导率43% , 并可直接从愈伤组织表面分化出不定芽, 分化率为69.2%; 腋芽启动培养基为MS + 6-BA 1~1.5 mg·L - 1 + NAA 0.5 mg·L - 1 , 萌动率为77%; 继代和增殖培养基为MS + 6-BA 1 mg·L - 1 +NAA 0.25 mg·L - 1 , 平均增殖系数为16.7; 生根壮苗培养基为1 /2MS +NAA 0.25 mg·L - 1 , 生根率96.1%; 试管苗生根培养30~35 d移栽, 成活率最高可达90%以上。 相似文献
15.
J. F. McConnell BVM&S DVR DipECDVI Cert. SAM MRCVS L. Garosi DVM S. R. Platt BVM&S 《Veterinary radiology & ultrasound》2005,46(1):1-10
The magnetic resonance imaging (MRI) findings of presumed cerebrovascular accident in 12 dogs are described. Fourteen lesions were seen, commonly (11 of 14) within the gray matter of the cerebellar hemispheres or vermis. Thirteen lesions were hyperintense on T2-weighted images (in 11 dogs) and one was hypointense. Eleven of 14 lesions were within the region supplied by the rostral cerebellar artery or one of its main branches and there was no, or minimal, mass effect. Contrast enhancement was only seen in six lesions and was mild in all. Gradient-echo images provided additional information in two dogs. The appearance of infarction in dogs with diffusion-weighted images (DWI) is similar to that in humans, and provided supportive evidence for the diagnosis of infarction in five dogs. The use of gradient-echo and DWI is recommended for the evaluation of suspected cerebrovascular accidents in dogs. Six of the 12 affected animals were spaniels or spaniel crosses, suggesting a possible breed predisposition. 相似文献
16.
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18.
M. C. Owen BVSC C. R. Lamb MA VETMB D. Lu BVET. MED. MVM M. P. Targett BA VETMB PHD 《Veterinary radiology & ultrasound》2004,45(2):149-155
The aim of this study was to determine the prevalence and potential significance of finding material in the middle ear of dogs having magnetic resonance (MR) imaging. Of 466 MR studies reviewed, an increased signal was identified in the tympanic bulla in 32 (7%) dogs. Cavalier King Charles spaniels, Cocker spaniels, Bulldogs, and Boxers were over-represented compared to the population of dogs having MR imaging. Five (16%) dogs had definite otitis media and one (3%) had a meningioma invading the middle ear. Of the remaining dogs, 13 (41%) had possible otitis media and 13 (41%) had neurologic conditions apparently unrelated to otitis media. The most common appearance of material in the middle ear was isointense in T1-weighted images and hyperintense in T2-weighted images. There was no apparent correlation between the signal characteristics of the material and the diagnosis. Enhanced signal after gadolinium administration was observed affecting the lining of the bulla in dogs with otitis media and in dogs with unrelated neurologic conditions. In dogs without clinical signs of otitis media, finding an increased signal in the middle ear during MR imaging may reflect subclinical otitis media or fluid accumulation unrelated to inflammation. Brachycephalic dogs may be predisposed to this condition. 相似文献
19.
Benjamin Young DVM Lisa Klopp DVM PhD Mark Albrecht DVM DACVS Susan Kraft DVM PhD 《Veterinary radiology & ultrasound》2004,45(6):538-541
This article describes the discovery of a chronic cervical wooden foreign body ventral to the left transverse processes of the cranial cervical spine using magnetic resonance imaging (MRI) in a dog that presented with chronic neck pain and lameness. The dog did not exhibit dysphagia or chronic draining tracts, the most common signs of the presumed cause, that of a penetrating oropharyngeal foreign body. The foreign body itself was represented on MR images as an oval straight-edged core within an inflammatory tissue reaction. The wood was slightly hyperintense on T2- and isointense on T1-weighted images relative to muscle. Surrounding this was a more conspicuous contrast-enhancing reactive tissue rim that was hyperintense on all pulse sequences. Adjacent musculature also exhibited diffuse edema and contrast enhancement that extended around the left cervical vertebral transverse processes and local intervertebral nerve roots. The foreign body was found to be a wooden stick upon surgical removal. MRI is an excellent method for visualizing the inflammatory tissue reactions associated with soft-tissue foreign bodies because of its contrast resolution and depiction of anatomy in multiple imaging planes. 相似文献
20.
猪肾脏中氯丙嗪和异丙嗪残留检测方法的建立 总被引:6,自引:0,他引:6
建立了猪肾脏中氯丙嗪和异丙嗪残留量检测的高效液相色谱法。猪肾脏中残留的氯丙嗪和异丙嗪,用乙腈提取,再依次用酸化乙腈和正己烷净化,氮气吹干,甲醇溶解后,用Waters高效液相色谱系统,HypersilC18柱,UV检测器,用V(乙腈)∶V(水)∶V(0.5mol·L-1乙酸铵)(50∶49∶1)为流动相,流速1.2mL/min,波长254nm测定,内标法定量。结果表明,氯丙嗪和异丙嗪在猪肾脏中的最低检测限均为10μg/kg,组织中添加量为10μg/kg时,氯丙嗪和异丙嗪的回收率分别为83%和84%,批间变异系数均小于20%。该方法样品处理简单,可同时检测氯丙嗪和异丙嗪在猪肾脏中的残留量。 相似文献