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81.
Nonphenolic β-O-4 lignin substructure model dimer, 1,3-dihydroxy-2-(2,6-dimethoxyphenoxy)-1-(4-ethoxy-3-methoxyphenyl)propane (I) was degraded by horseradish peroxidase (HRP) in the presence of hydrogen peroxide and 1-hydroxybenztriazole (HBT). 4-Ethoxy-3-methoxybenzoic acid (II), 1-(4-ethoxy-3-methoxyphenyl)-3-hydroxypropanone (III), 2,3-dihydroxy-1-(4-ethoxy-3-methoxyphenyl)-1-formyloxypropane (IV), 2,3-dihydroxy-1-(4-ethoxy-3-methoxyphenyl)propanone (V), 1-(4-ethoxy-3-methoxyphenyl)-1,2,3-trihydroxypropane (VI), 1-(4-ethoxy-3-methoxyphenyl)-1,2,3-trihydroxypropane-2,3-cyclic carbonate (VII), and 1-(4-ethoxy-3-methoxyphenyl)-1,2,3-trihydroxypropane-1,2-cyclic carbonate (VIII) were identified as degradation products by gas chromatography-mass spectrometry. These degradation products were qualitatively the same as those of substrate I in the laccase/HBT system, but the yield of the products was apparently different. The products catalyzed by the HRP/H2O2/HBT system contained large amounts of the aromatic ring cleavage products IV, VII, and VIII compared with those catalyzed by the laccase/HBT system, while the amount of Cα-Cβ cleavage product II is relatively low. These results suggest that the role of HBT is not in a simple one-electron transfer between the enzymes and substrates.  相似文献   
82.
ABSTRACT:   Changes in the number of respiratory pores (open pores) and their imprints (sealed pores) in post-larvae and juveniles were observed and compared for four abalone species Haliotis diversicolor , H. discus discus , H. madaka , and H. gigantea . The first open pore was evident at a shell length (SL) of 1.5 mm in H. diversicolor , 1.9–2.0 mm SL in H. discus discus , and 2.3–2.4 mm SL in H. madaka and H. gigantea . The number of open pores in H. diversicolor gradually increased with growth, with four to five pores at 2.5–18.0 mm SL and five to six pores at 18.0–27.0 mm SL. The other three species maintained four to five open pores after they reached 3.4–4.5 mm SL. The total number of open and sealed pores (TNP) was greater in H. diversicolor than in the other species at the same SL. Juvenile H. diversicolor were identified among field-caught abalone by the difference in the relationship between SL and TNP (SL–TNP relationship) and also by the monoclonal antibody reaction method. The results of the two methods were in perfect agreement, indicating that our method using the SL–TNP relationship is reliable for the identification of H. diversicolor .  相似文献   
83.
The current research concerned in the cloning, sequencing and phylogenetic analysis of inflammatory cytokine (IL-1alpha, IL-1beta, IL-6 and TNF-alpha) genes from swamp buffalo and two bubaline breeds, CB (cross between swamp and riverine type buffalo) and the Bulgarian Murrah buffalo. Multiple sequence comparison showed a high homology between the bubaline breeds, which ranged from 99.3% to 100.0% similarity, whereas from 98.6% to 99.0% compared to cattle. The phylogenetic analysis had confirmed and justified the degree of relationship between these bubaline species and their distinctness to each other by the bootstrap value (%) generated. These findings were discussed with particular attention to the diversity of the inflammatory cytokine proteins within closely related species. The result of this study concluded that a small difference in the cytokine structures might be the reason behind or has a contributory factor on the previous reports about the existence of disease resistance. However, in-depth study is necessary to further qualify these findings.  相似文献   
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85.
Intraneural perineurioma is an extremely rare condition characterized by perineurial cell proliferation within peripheral nerve (PN) sheaths. In the veterinary field, this entity has been reported only in a dog. We examined multiple enlargements of PNs in 11 chickens (Gallus gallus domesticus) (9 Japanese bantams and 2 specific pathogen-free White Leghorn), which were inoculated with an avian leukosis virus (ALV) causing so-called fowl glioma. All chickens clinically exhibited progressive leg paralysis. Lumbosacral plexus, brachial plexus, and/or spinal ganglion were commonly affected, and these nerves contained a diffuse proliferation of spindle cells arranged concentrically in characteristic onion bulb-like structures surrounded by residual axons and myelin sheaths. The spindle cells were immunohistochemically negative for S-100alpha/beta protein. Electron microscopy revealed that these cells were characterized by short bipolar cytoplasmic processes, occasional cytoplasmic pinocytotic vesicles, and discontinuous basal laminae. These features are consistent with those of intraneural perineurioma. Furthermore, the specific sequence of the ALV was detected in the PN lesions of 8/11 (73%) birds by polymerase chain reaction. These results indicate that the multiple intraneural perineuriomas of chicken may be associated with the ALV-A causing fowl glioma.  相似文献   
86.
本文研究了在内蒙古饲养管理条件下,降低牛奶含菌量的方法。共进行了5个方面的试验:头几把挤出的奶中细菌含菌量的检测;容器洗净对降低牛奶含菌量的作用;鲜奶过滤对奶中细菌含量的影响,冷水浴对降低牛奶含菌量的作用;盛奶罐口径大小及奶温高低对奶中细菌含菌量的影响。奶样抹片后,用纽曼染色液染色采用直接镜捡法进行细菌计数。结果表明:刚挤出的奶含有较多的细菌,随着挤奶的延续,奶中含菌量减少,彻底洗净挤奶器具和容器可大幅度降低牛奶的含菌量;用纱布过滤鲜奶并迅速冷却可明显降低牛奶的含菌量盛奶罐口径越大,牛奶中细菌含量越高。针对以上结果采取相应的对策,可降低牛奶中细菌的含量。  相似文献   
87.
Phosphoinositide 3-kinases (PI3Ks) regulate fundamental cellular responses such as proliferation, apoptosis, cell motility, and adhesion. Viable gene-targeted mice lacking the p110 catalytic subunit of PI3Kgamma were generated. We show that PI3Kgamma controls thymocyte survival and activation of mature T cells but has no role in the development or function of B cells. PI3Kgamma-deficient neutrophils exhibited severe defects in migration and respiratory burst in response to heterotrimeric GTP-binding protein (G protein)-coupled receptor (GPCR) agonists and chemotactic agents. PI3Kgamma links GPCR stimulation to the formation of phosphatidylinositol 3,4,5-triphosphate and the activation of protein kinase B, ribosomal protein S6 kinase, and extracellular signal-regulated kinases 1 and 2. Thus, PI3Kgamma regulates thymocyte development, T cell activation, neutrophil migration, and the oxidative burst.  相似文献   
88.
89.
The expression of sialyl Lewis X (sLe(x)) in 93 canine and 15 feline mammary gland tumors (MGT) obtained by surgical resection at Veterinary Medical Center, the University of Tokyo was examined by immunohistochemistry. Their clinicopathological features and prognosis were also reviewed. Approximately 60% of MGT tissues showed sLe(x) positive expressions, while all normal mammary gland tissues were negative. However, its expression was not correlated with clinicopathological features and prognosis significantly. This study suggests that sLe(x) may be a tumor-associated antigen in canine and feline MGTs.  相似文献   
90.
Plant–fungal specificity between cucurbitaceous crops and Diaporthe sclerotioides, the causal agent of black root rot, was studied using cucumbers (Cucumis sativa), melons (Cucumis melo), pumpkins (Cucurbita maxima), watermelons (Citrullus lanatus) and bottlegourd (Lagenaria siceraria var. gourda). Twelve D. sclerotioides isolates from these cucurbit species were cross‐inoculated. The virulence of the isolates was evaluated as the area under the disease progress curve (AUDPC). All cucurbit species were susceptible to each isolate, but AUDPCs were significantly different among the hosts, with the order of greatest to least being melon, cucumber, watermelon, bottlegourd and finally, pumpkin. The infectiveness of isolates was assessed as the quantity of D. sclerotioides DNA detected in the hypocotyls of seedlings 2 weeks after inoculation using a real‐time PCR protocol. The fungal DNA quantities varied among the species in the same order as the AUDPCs. Whilst there were statistically significant correlations between the virulence and infectiveness of D. sclerotioides isolates in cucumbers, melons and bottlegourds, their coefficients of determination were not high (r2 < 0·6). Orthogonal contrasts indicated no specificity in either the fungal virulence or infectiveness between D. sclerotioides isolates and the cucurbit hosts from which these isolates originated. Thus, although the degree of host susceptibility to D. sclerotioides varies among cucurbit species, the absence of specificity to the host species in either virulence or infectiveness suggests the pathogen may spread via various cucurbit crops, irrespective of their original host species.  相似文献   
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