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101.
Metaphyseal osteomyelitis is a rarely described condition in small animals, especially the cat. Infection, most commonly Staphylococcus sp, is considered to occur in the metaphyseal region of the immature animal due to vascular anomalies that predispose to the haematogenous seeding of bacteria in this area. There is also speculation that the characteristics of the bacteria that allow them to adhere to cartilage matrix, rather than vascular linings and erythrocytes, may provide an advantage for colonisation in the metaphysis, resulting in infection. This case describes the successful management of a case of distal radial metaphyseal osteomyelitis in an immature cat using surgical intervention and antibacterial therapy.  相似文献   
102.
鸡新城疫病毒HN基因亚单位疫苗诱导免疫保护的实验研究   总被引:3,自引:0,他引:3  
实验分别将应用Bac to Bac系统表达的新城疫病毒四平株和长春株血凝素-神经氨酸酶基因(HN基因)蛋白的重组杆状病毒感染Sf-9昆虫细胞后28℃培养72h后,洗涤、收集昆虫细胞,离心浓缩,-20℃冻融3次,用HA-HI实验和HN单抗中和试验测定表达产物的活性,将表达的重组蛋白作为亚单位疫苗免疫鸡,用间接ELISA和HI试验测定鸡体内抗体效价,免疫后第15d用国家标准强毒NDVF48E8攻毒,统计免疫保护率,结果表明,表达的NDVHN重组蛋白能够诱导鸡体产生抗NDV特异性IgG抗体和HI抗体,实验Ⅰ组(四平株)雏鸡保护率为65%,实验Ⅱ组(长春株)雏鸡保护率为100%。  相似文献   
103.
试验旨在探究不同乳酸菌发酵乳对高血脂模型大鼠血脂与肠道菌群的调节作用。将体重为(120±10)g的 40 只 SD 雄性大鼠随机分为空白对照组(C 组)、高脂模型组(M 组)、L. rhamnosus LV108 发酵乳组(LV组)及混合乳酸菌(LV108 发酵乳∶grx08 发酵乳∶grx12 发酵乳=2∶1∶1)发酵乳组(H 组),每组 10 只,建模后干预(1 mL/100 g,1×108 CFU/mL)4 周,测定大鼠血脂及大鼠粪样细菌 16S rDNA 的 V3-V4 区,并对大鼠肠道微生物和血清血脂水平的相关性进行分析。结果表明:LV 组和 H 组大鼠血清中甘油三酯、总胆固醇及低密度脂蛋白胆固醇含量显著降低,体重增长被抑制;LV 组和 H 组中大鼠肠道菌群的丰度及多样性显著提高,且 H 组大鼠肠道菌群的丰度高于 LV 组(P<0.05);LV 组和 H 组大鼠粪便中 Lactobacillus spp.、S24-7 spp 和 Treponema spp.等菌属显著升高,Peptostreptococcus spp.、Clostridium spp.、Turicibacter spp、Escherichia spp.及 Desulfovibrio spp.等菌属显著降低。结果提示,L. rhamnosus LV108发酵乳及混合乳酸菌发酵乳均能改善大鼠血脂水平并恢复大鼠肠道菌群的多样性及菌群构成。  相似文献   
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The degradative capabilities of six heavy-metal-affected and six unaffected bacterial communities from Canadian and German soils were determined by enumerating colony-forming units on 20 specific media. Each of these contained an aromatic substrate as the sole source of C and energy. Comparisons of plate counts revealed that heavy metal stress caused a decrease in the eveness of the distribution of the 20 degradative capabilities This suggests that in heavy-metal-affected bacterial communities, relatively rare degradative capabilities, irrespective of their nature, are even rarer than in unaffected communities, while the reverse is true for more common capabilities. The results are discussed with respect to the ease with which aromatic substrates can serve as C and energy sources.  相似文献   
106.
The synchronization of follicular waves with medroxyprogesterone acetate (MAP) and oestradiol‐17β (E2‐17β) prior to ovarian superstimilation in anoestrous ewes reduces the variability in superovulatory responses by an unknown mechanism. Follicle stimulating hormone (FSH) is a primary promoter of antral follicular development, but the relevance of circulating FSH concentrations to the superovulation performance in ewes has not been examined. Eighteen anoestrous Rideau Arcott ewes (May–June) were superovulated with Folltropin®‐V (porcine FSH), with (n = 8; treated ewes) or without (n = 10; control ewes) a single i.m. dose of 350 μg of E2‐17β, given on the sixth day of a 14‐day treatment with MAP‐releasing intravaginal sponges (60 mg). The superovulatory treatment, begun 6 days after E2‐17β injection, consisted of six i.m. applications of Folltropin®‐V given twice daily (at 08:00 and 16:00 h), followed by an i.m. injection of GnRH (50 μg). Blood samples collected every 8 h throughout the 3‐day treatment, were analysed by radioimmunoassays for concentrations of ovine and porcine FSH, using species‐specific standards and primary antibodies. Serum concentrations of oFSH were greater (p < 0.05) in the controls compared to treated ewes at 40, 64 and 72 h and the variability in mean oFSH concentrations was greater (p < 0.05) in control ewes at 40, 48, 64 and 72 h after the 1st Folltropin®‐V injection. There were no differences (p > 0.05) between the two groups in serum concentrations of pFSH. Significant correlations were recorded between the number of corpora lutea (CL) and oFSH concentrations at 8 h (r = 0.72, p < 0.05), 16 h (r=0.63, p < 0.05) and 64 h (r = 0.84, p < 0.01) after the 1st Folltropin®‐V injection. The total number of recovered embryos was positively correlated to oFSH concentrations at 56 h (r = 0.69, p < 0.05). We concluded that changes in endogenous FSH concentrations during ovarian superstimulation with pFSH might contribute to the variability in superovulatory responses in ewes.  相似文献   
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109.
Important differences exist between in vitro fertilized (IVF) and nuclear transfer (NT) bovine embryos. Studies have shown that although in vitro development is comparable, post-implantation survival is greatly reduced in NT embryos. In this study, we compare serum and bovine serum albumin (BSA) supplementation during oocyte maturation and embryo culture of IVF and NT embryos. In experiment 1, oocytes and embryos were randomly distributed into different treatment groups consisting of synthetic oviductal fluid (SOF) medium supplemented with either serum, fatty acid-free BSA (FAF) or fraction V BSA during maturation and/or culture to assess IVF embryo development. In experiment 2, oocytes were matured in SOF + serum or SOF + FAF and reconstructed embryos were cultured in SOF + FAF to assess NT embryo development. Among the IVF treatment groups, a greater number of blastocysts were observed in the steer serum (SER) group (IVM and IVC in SOF + serum) on day 6; however, no significant differences were seen in blastocyst development from day 8 onwards. Hatching frequencies on days 8 and 9 were significantly greater in groups with serum, with the exception of FAF (IVM and IVC in SOF + FAF) on day 9. For the NT treatment groups, the presence of serum during IVM resulted in a higher proportion of MII oocytes and increased blastocyst development and hatching rates were compared with supplementation of FAF. These results indicate that both serum and FAF provide comparable embryo development for IVF but not for NT bovine embryos.  相似文献   
110.
Adult articular cartilage is divided by the tidemark into a deep calcified layer and a more superficial uncalcified layer. Histologic examination of articular cartilage from the knee joint of golden Syrian hamsters 123 days of age or older revealed defects at the tidemark in the tibia. Defects ranged from small separations of the calcified and uncalcified layers along the tidemark to progressively larger defects apparently formed by dissolution. These larger defects appeared as cavities in the noncalcified cartilage, had smooth rather than rough edges, frequently contained coalesced debris, and often resulted in a bulge in the articular surface. Occasionally, these large defects broke through the articular surface. Defects were not observed in tibial cartilage of younger (<90 days old) hamsters or in femoral cartilage from hamsters of any age. Exercise neither protected against nor increased the severity of the defects. Collagen cross-linking by pyridinoline was examined as a function of age and increased from 1,090 to 3,062 micromoles of pyridinoline/mole of hydroxyproline over the period of 1-9 months of age but was not correlated with defect formation. With increasing age, these focal tidemark defects could lead to osteoarthrosis-like cartilage lesions.  相似文献   
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