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The expression and modulation of IL-1 alpha in murine keratinocytes   总被引:6,自引:0,他引:6  
Murine and human keratinocytes produce an IL-1-like factor that appears to be similar if not identical to monocyte-derived IL-1. IL-1 may be an important mediator in cutaneous inflammatory responses, however, little is currently known concerning factors that may modulate IL-1 expression in keratinocytes. To address this issue we examined the effect of LPS, UV, and the cell differentiation state on murine keratinocyte IL-1 mRNA expression. Our results indicated that as with the murine P388D1 monocyte cell line, PAM 212 keratinocytes constitutively express abundant amounts of IL-1 alpha mRNA. On exposure to LPS (100 micrograms/ml) for 8 h there was more than 10 times the increase in PAM 212 IL-1 alpha mRNA which was accompanied by a sixfold increase in supernatant IL-1 activity. Similarly UV irradiation had a significant effect on keratinocyte IL-1 alpha expression. High dose UV (300 mJ/cm2) inhibited PAM 212 IL-1 alpha expression at 4, 8, 24, 48 h post-UV whereas a lower dose of UV (100 mJ/cm2) inhibited UV at 4 and 8 h post-UV, but induced IL-1 expression at 24 and 48 h post-UV. The expression of IL-1 alpha varied with the differentiation state of the keratinocytes. Freshly removed newborn murine keratinocytes were found to constitutively express IL-1 alpha mRNA. Keratinocytes grown in low [Ca2+] tissue culture media (0.05 mM) for 6 days, functionally and phenotypically become undifferentiated and express increased quantities of IL-1 alpha mRNA, whereas cells grown in high [Ca2+] media (1.2 mM) for 6 days become terminally differentiated and IL-1 expression ceased. Keratinocytes cultured for 3 days in low [Ca2+] conditions expressed an intermediate level of IL-1 alpha. In contrast, little or no IL-1 beta mRNA was detected in either the PAM 212 cells or newborn murine keratinocytes. Thus LPS, UV, and cell differentiation state have a significant effect on expression of IL-1 alpha in murine keratinocytes.  相似文献   
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Summary The production of double-yolked eggs and its relation to other egg production traits has been summarized over a period of thirty years for a closed flock selected for gains in total egg production.The number of double-yolked eggs per pullet as well as the percentage of pullets laying at least one double-yolked egg have increased rather steadily, although it is evident that the trait possesses no selective advantage. Pullets which laid double-yolked eggs showed earlier sexual maturity and superiority in egg production but it is clear that the corresponding genetic correlations are low or negligible.The heritability of the trait increased with its level of incidence and is sufficiently high that selection should increase the incidence to a level permitting further study of multiple ovulation.
Zusammenfassung An einer für eine Steigerung der Ei-Produktion ausgewählten Herde Weißer Leghornhühner wurde der Anfall von Eiern mit zwei Dottern und ihre Beziehung zu anderen Merkmalen der Ei-Produktion für einen Zeitraum von 30 Jahren zusammengestellt.Die Anzahl doppeldottriger Eier je Hühnchen und der Prozentsatz Hühnchen, die wenigstens ein doppeldottriges Ei legten, ist ziemlich konstant geblieben, wenn auch dieses Merkmal offensichtlich keinen Selektionswert hat. Hühnchen, die Eier mit zwei Dottern legten, zeigten eine frühere Geschlechtsreife und eine höhere Ei-Produktion, aber es ist klar, daß die entsprechenden genetischen Korrelationen niedrig sind.Die Erblichkeit des Merkmals stieg mit seinem Auftreten, sie ist hoch genug, daß eine Selektion das Auftreten noch steigern könnte, um eine weitere Untersuchung der mehrfachen Ovulation zu ermöglichen.


Dedicated to Professor Hans Stubbe on the occasion of his 65th birthday.  相似文献   
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Selection for Egg Number with X-Ray-Induced Variation   总被引:1,自引:1,他引:0       下载免费PDF全文
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R. B. Lowry  B. L. Tamboline  A. Bogoch 《CMAJ》1965,93(23):1205-1207
The present study was undertaken to determine the frequency with which undigested meat fibres in the stool could be found after partial gastrectomy. A sample of stool was examined in 61 patients who had undergone a partial gastrectomy and in 92 control patients. The age ranges and average ages of both groups were similar. The stools of 77 of the 92 control patients contained well-digested meat fibres, 14 showed partially digested fibres, and one patient had completely undigested meat fibres. In the postgastrectomy group, 44 of 61 patients had well-digested meat fibres and 17 showed partially digested fibres in their stools. None showed undigested fibres. The present study demonstrated that the finding of undigested meat fibres is as infrequent in postgastrectomy patients as in control patients. If undigested meat fibres are found in the stools of postgastrectomy patients, it is suggestive of pancreatic exocrine insufficiency.  相似文献   
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