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221.
Interleukin-6 (IL-6) relays an important signal to hepatocytes during the early stages of an acute inflammatory response, causing an alteration in the expression of several major defense proteins. Additional regulation of this signal could occur either by altering the number of IL-6 receptors (IL-6-R) or of the signal transducing protein, gp130. We employed ribonuclease protection assays to measure the expression of IL-6-R and gp130 mRNA in primary rat hepatocytes in response to IL-6, interleukin-1, dexamethasone, and combinations thereof. Dexamethasone increases receptor mRNA levels 2.7-fold above controls but has no detectable effect on that of gp130. Such treatment increased surface expression of IL-6-R from 600 receptors per cell to greater than 6000, without a change in Kd (2.5-4.6 x 10(-10) M). In contrast to the stimulatory effect of the steroid signal, the inflammatory cytokines, individually and together, down-modulated both the mRNA and the cell surface expression of IL-6-R. These findings demonstrate for the first time that a sensitive control system exists between inflammatory mediators and IL-6-R.  相似文献   
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The female sex pheromone complex of the striped rice borer, Chilo suppressalis, has been shown to consist of two compounds: (Z)-11-hexadecenal (I) and (Z)-13-octadecenal (II). The pheromones were identified by gas chromatographic analysis, electroantennogram recording, ozonolysis, and comparison with synthetic material.  相似文献   
225.
Recent expansion of Medicaid eligibility for pregnant women and increased reimbursement to physicians who provide perinatal services were designed to improve access to care. Family physicians provide a relatively high proportion of care to pregnant women on Medicaid, especially in rural areas. We surveyed all family physicians who provide obstetric services in 26 northern California counties regarding these changes and perceived barriers to providing obstetric care to women on Medicaid. Of surveyed physicians who limited the number of their Medicaid obstetric patients, 58% stated that recent Medicaid policy changes had increased their willingness to accept new Medicaid obstetric patients. Despite these policy changes, administrative issues and poor reimbursement were cited as the two most notable barriers to providing obstetric care to women on Medicaid. Fear of being sued by Medicaid patients is still seen as a barrier by physicians who have recently discontinued practicing obstetrics and by those who continue to care for a large number of Medicaid obstetric patients.  相似文献   
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A wild relative of the garden pea, formerly called Pisum sativum L., but now included in the genus Lathyrus, is illustrated, and its relationship to cultivated peas is discussed. Recent studies of the DNA of Pisum and Lathyrus have led to the change of name for this common species.  相似文献   
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Ovipositor washings from virgin female Cryptophlebia batrachopa (Meyrick) (Lepidoptera: Tortricidae) were analysed by gas chromatography (GC) linked to electroantennography (EAG) and by high-resolution GC. The major EAG-active component in ovipositor washings was shown to be (Z)-8-dodecenyl acetate with less than 0.5% of the E isomer. GC analysis of ovipositor washings from C. leucotreta confirmed the presence of approximately equal amounts of (Z)- and (E)-8-dodecenyl acetates (Persoons et al., 1977). When pure (Z)-8-dodecenyl acetate and mixtures containing up to 50% of the E isomer were tested in the field in Malawi where both Cryptophlebia species occurred, C. batrachopa male moths were caught only in traps baited with 10% or less of the E isomer and highest catches were recorded for the pure Z isomer. By contrast C. leucotretra males were caught predominantly by traps baited with more than 10% E isomer and no catches were recorded for the pure Z isomer. (Z)-8-dodecenyl acetate containing 1% of the E isomer was found to attract male moths of Opogona spp.
Résumé Les produits recueillis par lavages de l'ovipositeur de Cryptophlebia batrachopa Meyr. (Lep. Tortricidae) ont été analysés par chromatographie gazeuse (GC) associée à l'électroantennographie (EAG) et la GC à haute résolution. Le principal constituant actif en EAG provenant des lavages s'est révélé être le (Z)-8-dodécényl acétate avec moins de 0,5% de l'isomère E. L'analyse GC de ces produits de lavage de C. leucotreta ont confirmé la présence d'à peu près les mêmes quantités de (Z) et (E)-8-dodécényl acétates (Persoons et al., 1977). Quand des essais sur le terrain ont été effectués au Malawi, où existent les deux espèces de Cryptophlebia, avec du (Z)-8-dodécényl acétate et des mélanges comprenant jusqu'à 50% de l'isomère E, des mâles de C. batrachopa ont seuls été capturés dans des pièges contenant 10% ou moins de l'isomère E; les captures les plus élevées ont été obtenues avec l'isomère Z pur. A l'opposé, surtout des mâles de C. leucotreta ont été capturés dans des pièges garnis avec plus de 10% d'isomère E, et aucune capture n'a été obtenue avec l'isomère Z pur. Des mâles d'Opogona spp. ont été attirés par du (Z)-8-dodécényl acétate contenant 1% de l'isomère E.
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229.
Cutaneous elevations were present on the feet, legs and heads of four Florida sandhill cranes, Grus canadensis pratensis, (one free-living, three penreared birds). As a result of examination of the elevations by light- and electron microscopy, it was determined that the lesions were caused by poxvirus. This is the first record of pox in cranes in North America.  相似文献   
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