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The tissue polarity genes control the polarity of hairs, bristles and ommatidia in the adult epidermis of Drosophila. We report here the identification of a new tissue polarity gene named starry night (stan). Mutations in this essential gene alter the polarity of cuticular structures in all regions of the adult body. The detailed polarity phenotype of stan on the wing suggested that it is most likely a component of the frizzled (fz) pathway. Consistent with this hypothesis, stan appears to be downstream of and required for fz function. We molecularly cloned stan and found that it encodes a huge protocadherin containing nine cadherin motifs, four EGF-like motifs, two laminin G motifs, and seven transmembrane domains. This suggests that Stan functions in signal reception, perhaps together with Fz.  相似文献   
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The pleiotropic effects of the insulin-sensitizing adipokine adiponectin are mediated, at least in part, by two seven-transmembrane domain receptors AdipoR1 and AdipoR2. Recent reports indicate a role for AdipoR-binding proteins, namely APPL1, RACK1 and CK2β, in proximal signal transduction events. Here we demonstrate that endoplasmic reticulum protein 46 (ERp46) interacts specifically with AdipoR1 and provide evidence that ERp46 modulates adiponectin signalling. Co-immunoprecipitation followed by mass spectrometry identified ERp46 as an AdipoR1-, but not AdipoR2-, interacting protein. Analysis of truncated constructs and GST-fusion proteins revealed the interaction was mediated by the cytoplasmic, N-terminal residues (1-70) of AdipoR1. Indirect immunofluorescence microscopy and subcellular fractionation studies demonstrated that ERp46 was present in the ER and the plasma membrane (PM). Transient knockdown of ERp46 increased the levels of AdipoR1, and AdipoR2, at the PM and this correlated with increased adiponectin-stimulated phosphorylation of AMPK. In contrast, adiponectin-stimulated phosphorylation of p38MAPK was reduced following ERp46 knockdown. Collectively these results establish ERp46 as the first AdipoR1-specific interacting protein and suggest a role for ERp46 in adiponectin receptor biology and adiponectin signalling.  相似文献   
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The Resource Allocation Working Party (RAWP) recognised the need to consider both health authority and primary care services in achieving its objective. RAWP and the subsequent Advisory Group on Resource Allocation (AGRA) found (but did not publish) considerable variation in resources used by both services but could not find a clear relation between them. Statistics provided by the DHSS were used to compare spending by 80 area health authorities in 1980-1 with expenditure per head on general medical services by their corresponding family practitioner committees. There was considerable variation in the provision of resources for both services and no clear relation between the variations in spending on each service. Only 40 of the 80 areas had both health authority and family practitioner committee spending levels within 10% of "target." Subregional inequalities in resources tend to be related to variations in admission rates, which in turn are related to general practitioners'' referral behaviour. These results emphasise the importance of finding out more about inequalities in the provision of general medical services and their relation to the use of hospital services. They also suggest that RAWP''s aim of equality of opportunity of access to health care resources may be achieved only if general medical services are brought into the equation as well.  相似文献   
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The effects of malnutrition on intracellular K+ activity, (alpha K)i, and membrane potential, Em, were measured by means of double-barrelled K+-selective microlectrodes in the soleus and gastrocnemius muscles of the rat. (alpha K)i and Em were measured in vivo in normal anaesthetized animals and in rats subjected to one of two diet restrictions: a 2-day fast or a long-term hypocaloric diet. In the soleus muscle, (alpha K)i fell by similar amounts in both 2-day fasted and long-term hypocalorically fed rats, while Em depolarized significantly only in hypocalorically fed rats. In the gastrocnemius muscle, neither the 2-day fast nor the hypocaloric diet affected (alpha K)i or Em. It is suggested that the selective loss of K+ from the soleus muscle may be related to its activity pattern.  相似文献   
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Enzyme measurements were carried out with crude cell-free extracts of the propionate oxidizing coculture of Syntrophobacter wolinii and Desulfovibrio G11. Using cell-free extracts of a pure culture of Desulfovibrio G11 as a blank, most of the enzymes involved in the methylmalonyl-CoA pathway for propionate oxidation, including a propionyl-CoA: oxaloacetate transcarboxylase, were demonstrated in S. wolinii.  相似文献   
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Summary A group of 15 patients with metastatic colorectal adenocarcinoma received a combination of interferon (0.1 mg/m2, days 1–15) and the murine monoclonal antibody 17-1A (400 mg, days 5, 7, 9 and 12). The treatment was tolerated with minimal toxicity. Of the 14 evaluable patients, 13 developed human antibody to murine 17-1A, with 11 patients demonstrating antibody to the variable region of 17-1A (anti-idiotype). Antibody to the variable region was inhibited by 17-1A but not by mouse immunoglobulin. Sera from patients with substantial anti-idiotype reactivity were capable of inhibiting the binding of murine 17-1A to antigen expressing LS174-T cells thus indicating the presence of antibody directed against the 17-1A combining site (mirror-image anti-idiotype). The median survival of the whole group was 56 weeks and there was no correlation between clinical response/survival and the development of anti-idiotype antibody.Supported by the Veterans Administration Medical Center and by Public Health Services grant CA 45 232 from the National Cancer Institute, National Institutes of Health, Department of Health and Human Services  相似文献   
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