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321.
Weaning causes atrophy of intestinal mucosa and a drop of IgA protection in piglets which increases vulnerability to pathogenic infections. Probiotic lactobacilli may support recovery from such weaning stresses. Butyrate‐produce bacteria may support the growth of colonic mucosa. Megasphaera elsdenii, a lactate‐utilizing butyrate producer, may help butyrate production particularly when combined with lactobacilli. Weaned piglets (Experiment 1: 20 days old, Experiment 2: 28 days old) were orally dosed once a day with either (L) 1010 (cell/dose) L. plantarum Lq80, or (LM) 1010 (cell/dose) Lq80 with 109 (cell/dose) M. elsdenii iNP‐001. Lq80 was contained in capsules resistant to gastric digestion. M. elsdenii was contained in capsules resistant to gastric and intestinal digestion. An untreated control (C) was also prepared. After 2 weeks of administration, L. plantarum enhanced the recovery from the villous atrophy in both experiments. The rectal and colonic IgA tended to be higher in L and LM than in C in Experiment 1. Colonic butyrate was higher in LM than in the others in Experiment 1. The thickness of the colonic mucosa was greater in LM than in the others in Experiment 1. In early weaned piglets, the effects of L. plantarum and M. elsdenii were clear.  相似文献   
322.
Leaf spots were found on Christmas rose (Helleborus niger) in Yamagata Prefecture, Japan, in October 2006. The morphology of the causal fungus was very close to that of Colletotrichum truncatum. Classifying the species from the sequences of the internal transcribed spacer regions of ribosomal DNA was inconclusive, and the isolates were identified only as Colletotrichum sp. Artificial inoculation confirmed the pathogenicity of isolates to the host plant and some legumes. We propose the name anthracnose of Christmas rose for this disease by Colletotrichum sp.  相似文献   
323.
The aim of this study was to establish a culture system to improve the meiotic competence of porcine oocyte-granulosa cell complexes (OGCs) obtained from preantral or early antral follicles. Porcine OGCs were recovered from follicles with diameters of 230-300 (preantral follicles), 300-500, and 500-700 mum (early antral follicles) using scalpels. The OGCs were cultured for 2 weeks in culture medium. We examined the effects of the sizes of the follicles from which OGCs were recovered, the concentrations of polyvinylpyrrolidone (PVP, 0-8%) in the culture medium, and 2 types of culture dish (Falcon 3002 vs 1007) on formation of the antrum of OGCs. After culture, the oocytes were matured for 44 h to assess their meiotic competence. OGCs recovered from small follicles (230-500 microm) required longer (P<0.05) than larger follicles to form the antrum structure. The percentage of OGCs forming the antrum structure that were cultured in 2% PVP (31%) was higher (P<0.05) than for those cultured in other PVP concentrations (0-11%). The percentages of antrum-structure formation for OGCs cultured on Falcon 3002 (83% for 2% PVP and 60% for 4% PVP) were higher (P<0.05) than those cultured on Falcon 1007 (47% for 2% PVP and 9% for 4% PVP). Furthermore, all of the intact oocytes that were obtained from culture of OGCs and that formed an antrum were in the GV stage (n=28). When these immature oocytes were cultured for 44 h, the percentage of oocytes that reached the metaphase II stage (25%, n=68) was higher (P<0.0001) than that of oocytes matured without culture (0.7%, n=137). The results of the present study show that porcine OGCs obtained from preantral or early antral follicles acquire meiotic competence in vitro.  相似文献   
324.
ABSTRACT:   Lipid class and fatty acid composition of phospholipids from the gonads of skipjack tuna were examined to evaluate effective utilization of the processing of by-products. The predominant phospholipids in the ovaries were phosphatidylcholine (PC; 47.9%), phosphatidylethanolamine (PE; 19.3%) and lyso-phosphatidylcholine (LPC; 19.1%). In contrast, those in the testes were PC (40.1%), PE (29.3%) and phosphatidylserine (PS; 9.6%). The percentage of docosahexaenoic acid (DHA) was markedly high at more than 50% in LPC of the ovaries, and PE and PS of the testes were also high. The percentages of DHA at sn-position 2 of the predominant phospholipids, except for PC in the testes, were more than 60%, in particular PE in the testes was remarkably high at 81.9%. After storage for 2 days at 5°C, the LPC content in the ovaries increased twofold and the DHA level of LPC was the same as before, though the contents of other phospholipids decreased.  相似文献   
325.
ABSTRACT:   The clonal triploid ginbuna crucian carp Carassius auratus langsdorfii , a naturally occurring gynogenetic fish, is a useful model for studying T-cell-mediated immunity. CD4, a T-cell receptor (TCR) coreceptor, is a membrane-bound glycoprotein found on helper T-cells, and assists in the binding of major histocompatibility complexes. In the present study, full-length cDNAs encoding the CD4 molecule from the S3n strain of ginbuna crucian carp were cloned and characterized. 5'-rapid amplification of cDNA ends (RACE) and 3'-RACE yielded two distinct cDNA clones of CD4 homolog from the ginbuna, and these sequences share 95% identity at the amino acid level. These ginbuna CD4 molecules consisted of a signal peptide, immunoglobulin superfamily (IgSf) like domains, a transmembrane domain, and a cytoplasmic domain similar to other known CD4. A tyrosine protein kinase p56lck binding motif is conserved in the cytoplasmic tail of ginbuna CD4. Phylogenetic tree analysis indicated that ginbuna CD4 sequences are closely related to CD4L-1 from other fish species. Expression of ginbuna CD4 mRNA was detected in the gill, thymus, head kidney, trunk kidney and peripheral blood leukocytes, indicating that its expression pattern is similar to that of ginbuna TCRβ mRNA. The results suggest that ginbuna CD4 sequences are useful as molecular probes for helper T-cells.  相似文献   
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