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Previous work has shown that male flesh flies (Sarcophaga crassipalpis Macquart) exhibit an ontogeny of behaviour from eclosion through sexual maturity that includes extensive changes in the expression of aggressive, non‐aggressive interactive and non‐interactive behaviours. To determine how the presence of a female flesh fly influences the manifestation of these behaviours, male flesh flies of different ages post‐eclosion are paired with same‐age females and their behaviours are monitored in a simple arena during a 50‐min observation period. All flies are socially isolated until pairing. Although the levels of expression of aggressive and non‐aggressive interactive behaviours are depressed relative to previous findings in male‐opponent pairs, the ontogeny of aggression still occurs as indicated by a significant increase, with age, in the agonistic behaviour ‘hold’. Similar to male‐opponent pairs and individual males, the performance by males of the non‐interactive behaviours ‘walking’ and ‘standing’ diminishes, whereas ‘upside‐down’ increases with age. By contrast, ‘grooming’ shows a significant age‐related decline. No courtship behaviours are observed in the males, although the aggressive behaviour ‘hold’ is a significant transition to mating. Females show no obvious courtship or rejection behaviours, although the significant increase in ‘upside‐down’ with age could possibly be a behavioural gateway to mating. The results of this study indicate that extensive age‐related changes encompassing the entire behavioural repertoire are intrinsic to male flesh flies and persist under a variety of different social contexts.  相似文献   
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Summary Biliary epithelial cells (BEC) lining the intra-hepatic biliary ducts are the site of damage in several immunologically mediated liver diseases. BEC are difficult to isolate since they represent only 5% of the total cell number in normal liver. In this communication, a novel method for their isolation from normal liver is presented using a monoclonal antibody (HEA125) with specificity for an epithelial cell surface glyco-protein reported to be expressed in liver only by biliary epithelium. By combining differential density centrifugation and immuno-magnetic separation using HEA125 pure BEC (105 cells/g fresh tissue) were prepared routinely. These cells were maintained in culture for up to 4 weeks with significant increases in cell numbers. The ability to prepare BEC from human liver offers an opportunity to develop In Vitro models to investigate the aetiology of diseases in intra-hepatic biliary epithelium. EDITOR’S STATEMENT This is a novel application to purification of specific liver cell types directly from tissue. It is well-suited for rapid communication because of its novelty and potential utility to investigators.  相似文献   
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In studies of calcium metabolism in 13 unselected patients with untreated sarcoidosis all were normocalcaemic but five had hypercalcuria. All had normal renal function. Calcium absorption was indexed by a double isotope test. 45Ca hyperabsorption occurred in six patients. Ten kinetic studies were carried out with 47Ca and in six bone turnover was increased. 45Ca absorption correlated well with the calculated bone uptake rate of calcium, and with urine calcium excretion. These results suggest that in sarcoidosis abnormalities in calcium metabolism are fairly common although they rarely result in sustained hypercalcaemia.  相似文献   
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Background  

Very often genome-wide data analysis requires the interoperation of multiple databases and analytic tools. A large number of genome databases and bioinformatics applications are available through the web, but it is difficult to automate interoperation because: 1) the platforms on which the applications run are heterogeneous, 2) their web interface is not machine-friendly, 3) they use a non-standard format for data input and output, 4) they do not exploit standards to define application interface and message exchange, and 5) existing protocols for remote messaging are often not firewall-friendly. To overcome these issues, web services have emerged as a standard XML-based model for message exchange between heterogeneous applications. Web services engines have been developed to manage the configuration and execution of a web services workflow.  相似文献   
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Introduction  

The vast difference in the abundance of different proteins in biological samples limits the determination of the complete proteome of a cell type, requiring fractionation of proteins and peptides before MS analysis.  相似文献   
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A total of 78 acromegalic patients were studied before and after treatment by yttrium-90 needle implantation.Among the untreated patients 16% had a borderline or raised serum calcium. In half of these patients the serum calcium fell to normal after remission of their acromegaly. In the others the hypercalcaemia was due to associated proved or probable hyperparathyroidism. A downward trend of the serum calcium was noted even in the normocalcaemic patients with remission of their disease.Only 20% of untreated patients had a raised serum phosphate, and follow-up showed this measurement to be a poor index of disease activity.Net calcium absorption and calcium balances in five patients in this series and 12 others from the literature were essentially normal for their given level of calcium intake. No patient showed definite radiological evidence of osteoporosis and vertebral fractures.Bone uptake rate of calcium-47 and stable strontium was raised in the untreated state in all nine patients studied. The 24-hour strontium space was raised in 73% of untreated patients and fell to normal after treatment in all the retested patients in whom it was high initially.  相似文献   
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