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In six experimental dogs, arthrographic quality and synovial inflammatory response with shoulder arthrography comparing meglumine-sodium diatrizoate (Urovison) and the monoacidic dimer, meglumine-sodium ioxaglate (Hexabrix) was evaluated. In our study initial films were of equally high diagnostic quality for both contrast media, but delayed films significantly favored ioxaglate for diagnostic quality. The rise in white blood cells in synovial fluid samples collected 24 hours after the arthrographic procedure was significantly lower after the use of ioxaglate. Histologic examination performed 14 days after the intra-articular injection revealed no drug related lesions.  相似文献   
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Tumour necrosis factor (TNF), a polypeptide produced by mononuclear phagocytes, has been implicated as an important mediator of inflammatory processes and of clinical manifestations in acute infectious diseases. To study further the potential role of TNF in infectious diseases, recombinant Escherichia coli (E. coli) derived human (r.HuTNF-alpha) and bovine TNF (r.BoTNF-alpha) were intravenously (i.v.) administered in dwarf goats. Rectal temperature, heart rate, rumen motility, plasma zinc and iron concentrations, and certain other blood biochemical and haematological values were studied and compared with the changes seen after E. coli endotoxin (LPS) was administered (dose: 0.1 microgram/kg i.v.). Following a single injection of 4 micrograms/kg of r.BoTNF-alpha, shivering and biphasic febrile response were observed, accompanied by tachycardia, inhibition of rumen contractions, drop in plasma zinc and iron concentrations, lymphopenia, and neutropenia followed by neutrophilia. The i.v. administration of a single injection of 4 micrograms/kg r.HuTNF-alpha induced shivering and biphasic febrile responses, accompanied by anorexia and a similar drop in plasma trace metal concentrations when compared with r.BoTNF-alpha-treated goats. The TNF-alpha-induced symptoms were essentially the same as those that occurred after LPS administration. However, the time of onset of these changes after the injection of TNF-alpha was significantly shorter than after LPS. Moreover, the r.BoTNF-alpha induced a longer lasting neutrophilic leucopenia, less neutrophilia, and a more persistent lymphopenia than after LPS injection. Neither r.BoTNF-alpha nor LPS caused severe haemo-concentration. Furthermore, no cross-tolerance between r.BoTNF-alpha and LPS could be demonstrated. We conclude that both r.BoTNF-alpha and r.HuTNF-alpha induce many of the physiologic, haematologic and metabolic changes that characterize the acute phase response to LPS. The overlapping biological activities of r.BoTNF-alpha, r.HuTNF-alpha and LPS in dwarf goats may indicate that both recombinant tumour necrosis factors have some homology with caprine TNF-alpha.  相似文献   
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Amplified fragment length polymorphism (AFLP) analysis was used to study genetic variation among 76 isolates of Verticillium. A dendrogram based on the AFLP data revealed three main groups. One group consisted of 35 European isolates derived from Brassica napus together with five Californian isolates taken from B. oleracea. This group displayed a high degree of genetic similarity and included three isolates earlier classified as Verticillium longisporum, indicating that all isolates in this group probably should be regarded as members of V. longisporum. V. dahliae isolates constituted the second group while the third group contained four V. albo-atrum isolates. In addition to these three groups, a cluster of six V. nigrescens isolates was observed. However, the genetic distances between the isolates of V. nigrescens were much higher than those between members in the other groups and the bootstrap value for the V. nigrescens cluster was subsequently low. Four isolates classified as V. tricorpus were highly diverse and did not cluster together. Analysis of molecular variance revealed that the isolates of V. longisporum were separated into four subgroups, based on geographic origin. The study furthermore shows that AFLP is a suitable method for studying population structure in Verticillium.  相似文献   
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微管、微丝特异性抑制剂处理对水稻抗病性的影响   总被引:3,自引:0,他引:3  
 微管特异性抑制剂oryzalin、微丝特异性抑制剂细胞松弛素A (cytochalasin A,CA)和细胞松弛素D (cytochalasin D,CD)的试验表明:oryzalin在5~50μmol/L、CA在0.5~1.0μg/mL、CD在1~20μg/mL的浓度范围内,对稻瘟病菌孢子的萌发和附着胞的形成基本上没有影响。采用以上几种细胞骨架特异性抑制剂处理水稻叶鞘都可以不同程度地抑制寄主细胞抗病菌扩展的能力。在抑制剂处理的水稻叶鞘细胞中,病菌扩展的速度加快。进一步的观察发现,抑制剂处理抑制水稻细胞抗病菌的扩展能力与水稻的抗病防卫反应如原生质颗粒化、多酚类物质的积累和HR发生的延迟是相关的。  相似文献   
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In recent years, the interest in equine foetal gender determination (FGD) during gestation increased remarkably. Ultrasonographic FGD can be performed in two different periods during gestation. The earliest examination can take place at a gestational age of 60–70 days, whereby the genital tubercle is used to differentiate between male and female foeti. The time window of the second approach is wider (120–210 days), and there are more characteristics to take into consideration. In this article, the feasibility and accuracy of ultrasonographic FGD in mid‐ to late gestation are evaluated. One hundred twenty‐one mares from different breeds with a pregnancy stage between 120 and 270 days were examined once, using B‐scale ultrasonography (Esaote MyLab™ClassC). None of the mares were sedated nor shaved, and the procedure was completed within 15 min. Diagnosis was firstly based on the gonads. The final judgement was made based on all visible foetal reproductive organs. In three cases with a pregnancy stage beyond 257 days, FGD was not possible. All of the examined mares in which a FGD could be performed gave birth to a healthy foal. In 98% of the examinations (116/118), the diagnosis was correctly made. In both cases of misdiagnosis, only one characteristic was seen during the procedure and wrongly interpreted. Beyond 210 days of pregnancy, the extremities can preclude a good visualization of the inguinal region. In conclusion, equine FGD in mid‐ to late gestation is an accessible and accurate technique, although a good ultrasound device is a prerequisite and experience and expertise is necessary.  相似文献   
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