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91.
Oocysts of the Weybridge and Houghton strains of Eimeria maxima and a fresh field isolate were similar and measured on average 30-9 X 22-4 mum. The Weybridge strain and the field isolate produced similar pathogenic effects in 6-week-old chickens, high doses causing 50-80% mortality and severe weight loss. The Houghton strain was slightly less pathogenic and few birds died but more oocysts were produced. With each strain, a single dose gave complete immunity to a light challenge with the homologous strain. Two or 3 immunizing doses gave complete immunity to a heavy homologous challenge but were not sufficient to protect against heterologous challenge. 相似文献
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Dermal and glomerular deposition of IgA in anaphylactoid purpura 总被引:1,自引:0,他引:1
During the period of acute anaphylactoid purpura, skin biopsies were performed on 14 patients with purpuric and nonpurpuric skin. In addition, four patients had renal biopsies. Examination of the tissue by immunofluorescence to anti-human immunoglobulins IgG, IgA, IgM, and IgE, fibrin/fibrinogen, complement Clq, C4, and C3 demonstrated predominant IgA, C3, fibrin/fibrinogen in the purpuric skin and glomerulus, without Clq and C4. These immunohistochemical findings are characteristic of anaphylactoid purpura and suggest that IgA is involved in the pathogenesis of anaphylactoid purpura and may operate through the alternate pathway of the complement system. 相似文献
96.
A system for the quantitative assessment of uterine activity during an oxytocin-induced labour has been developed. This has been achieved using relatively simple analogue techniques and can easily be used in the labour ward alongside existing monitoring equipment. Initial results indicate that a plateau of uterine activity can be easily recognised from the display and maintained at oxytocin dosage levels below those that might normally be used. 相似文献
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1月,备受关注的年度大戏《孔子》将亮相荧屏。在其中饰演霓裳的李欣汝,一个从古典舞中走出的女子,形神兼具的身韵翩然跳出最优美的舞姿,带你进入千年以前,那个烽火连天却笙箫依旧的春秋战国,领略中华名族的根髓。 相似文献
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Signals mediated by G-protein-linked receptors display agonist-induced attenuation and recovery involving both protein kinases and phosphatases. The role of protein kinases and phosphatases in agonist-induced attenuation and recovery of beta-adrenergic receptors was explored by two complementary approaches, antisense RNA suppression and co-immunoprecipitation of target elements. Protein phosphatases 2A and 2B are associated with the unstimulated receptor, the latter displaying a transient decrease followed by a 2-fold increase in the levels of association at 30 min following challenge with agonist. Protein kinase A displays a robust, agonist-induced association with beta-adrenergic receptors over the same period. Suppression of phosphatases 2A and 2B with antisense RNA or inhibition of their activity with calyculin A and FK506, respectively, blocks resensitization following agonist removal. Recycling of receptors to the plasma membrane following agonist-promoted sequestration is severely impaired by loss of either phosphatase 2B or protein kinase C. In addition, loss of protein kinase C diminishes association of phosphatase 2B with beta-adrenergic receptors. Overlay assays performed with the RII subunit of protein kinase A and co-immunoprecipitations reveal proteins of the A kinase-anchoring proteins (AKAP) family, including AKAP250 also known as gravin, associated with the beta-adrenergic receptor. Suppression of gravin expression disrupts recovery from agonist-induced desensitization, confirming the role of gravin in organization of G-protein-linked signaling complexes. The Ht31 peptide, which blocks AKAP protein-protein interactions, blocks association of beta-adrenergic receptors with protein kinase A. These data are the first to reveal dynamic complexes of beta-adrenergic receptors with protein kinases and phosphatases acting via an anchoring protein, gravin. 相似文献
100.
BACKGROUND: Previous studies questioned the link between early childhood anemia and detrimental child development. OBJECTIVE: A population-based study was conducted to examine the association between early childhood anemia and mild or moderate metal retardation at 10 y of age. DESIGN: The present study linked early childhood nutrition data collected by the Special Supplemental Program for Women, Infants, and Children (WIC) and school records. Hemoglobin values were used to determine the relation between anemia in early life and children's placement in special education classes for mild or moderate mental retardation. Subjects were all participants in the WIC program. A computer program was used to link data from birth, WIC, and school records. RESULTS: Logistic regression showed an increased likelihood of mild or moderate mental retardation associated with anemia, independent of birth weight, maternal education, sex, race-ethnicity, the mother's age, or the child's age at entry into the WIC program. CONCLUSION: These findings support the proposition that efforts to prevent mild and moderate mental retardation should include providing children with adequate nutrition during early childhood. 相似文献