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A monoclonal antibody, C215, was first internally labelled with 75Se-methionine and then labelled with 125I. The biodistribution of the dual-labelled [125I][75Se]C215 was studied in tumour-bearing nude mice killed 3 days after injection. The biodistribution of the dual-labelled [125I][75Se]C215 was compared with the biodistribution of single-labelled [131I]C215 and [75Se]C215. Iodine-labelled antibodies seem to be damaged during iodination, affecting the disappearance rate and tumour uptake. There were no signs of dehalogenation of circulating antibodies or antibodies taken up in the tumour.  相似文献   
43.
All cases of adenocarcinoma in the duodenum (n = 263) and jejunum/ileum (n = 663), diagnosed between 1960 and 1988, were recruited from the Swedish Cancer Registry. Corrected and overall survival were investigated by sex, age and year of diagnosis with life-table and Cox proportional hazards analyses. The corrected 5- and 10-year survival rates were 39% and 37% for duodenal tumours and 46% and 41% for those in jejunum/ileum (P = 0.16 for difference between sites). The corrected 5- and 10-year survival rates were 52% and 48% for women and 40% and 34% for men with tumours in jejunum/ileum (P = 0.0095 for difference by sex) while no such relation was found in duodenal tumours (P = 0.84). Survival correlated with age at diagnosis for duodenal tumours (P = 0.03377). A Cox proportional hazards analysis revealed a temporal trend with more favourable prognosis in recent years. This study confirms that prognosis of small bowel adenocarcinoma is serious, but gives a more optimistic outlook than many hitherto published series.  相似文献   
44.
We discuss the problem of designing a telecommunication network with the survivability requirement that the network should be composed of connected rings of links. The network design problem is then to choose links from a given network, and compose them into a number of rings. Furthermore, the rings should be connected at certain transit nodes. The traffic between rings may pass through other rings. Each ring is associated with a certain fixed cost depending on the length of the ring. We describe the problem, modeled as a linear integer programming problem, and a heuristic solution method, based on column generation and Lagrangean relaxation.  相似文献   
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Time series cross-correlation analysis was used to determine relationships among serum beta-hydroxybutyrate, glucose, FFA, cholesterol, milk yield, DMI, and estimated net energy balance for 42 d postpartum for 14 multiparous cows. Milk yield was positively associated with beta-hydroxybutyrate concentrations on the same day, and milk yield was a primary determinant of metabolic change. Dry matter intake was negatively correlated with beta-hydroxybutyrate concentrations 3 d later and on the same day. The data supported in vitro studies showing that FFA are positively associated with beta-hydroxybutyrate production, showed that glucose concentrations are negatively cross-correlated with beta-hydroxybutyrate concentrations, and found that estimated net energy balance is negatively cross-correlated with beta-hydroxybutyrate. Analyses suggested that serum glucose and cholesterol concentrations significantly decreased with increased milk yield; analyses also suggested that elevated beta-hydroxybutyrate concentrations were associated with decreases in milk yield 6 d later. beta-Hydroxybutyrate and FFA concentrations 3 to 9 d before parturition were positively related to cholesterol concentrations, and relationships were positive between estimated net energy balance and cholesterol, suggesting that cholesterol concentrations increased as precursors for cholesterol synthesis were available. Time series cross-correlation analysis was a useful tool in examining relationships among variables when repeated samples were obtained from the same individuals.  相似文献   
47.
Concentrated contacts in motion are found in most mechanical machines. The elasto-hydrodynamic lubrication (ehl) theory deals with the lubrication of moving concentrated contacts. The first important successful application of ehl was to rolling contact bearings. The theory can today be used by designers for optimizing bearing design and predicting bearing life, power loss, temperature and dynamic behaviour. The application of ehl to gearing is more complicated. The simplified film thickness calculation methods for gears offer a practical way of making a rough estimation of the risk of failure. Methods for calculating the film thickness in the difficult transient contact conditions and along the gear contact have recently been developed. The application of ehl to the transient conditions in a cam and tappet contact is promising but needs more work. To achieve better methods for the design of lubricated concentrated contacts, a better understanding of microgeometry and thermal and chemical effects in the contact is required  相似文献   
48.
Cumulative Time Statistics of Surface-Point Rainfall Rates   总被引:1,自引:0,他引:1  
Statistics on rainfall rates near and above the earth's surface are needed in order to estimate the percentage of time of absorption, or scattering of radio waves that affect radio system design and electrospace management. The most useful averaging time for computing such rates is on the order of 1 min or less. This paper extrapolates excessive short-duration precipitation data to provide such statistics from data routinely reported by the National Weather Service. For the 8766 h in an average year, and for a median or random location in any part of the world, the model described here estimates the fraction of time during whicht-minute average rainfall rates exceed any given value.  相似文献   
49.
An den normalgeglühten Stählen 13 CrMo 4 4 mit 0,14% C, 0,85% Cr und 0,50% Mo und 10 CrMo 9 10 mit 0,08% C, 2,06% Cr und 0,95% Mo Untersuchung der bei langzeitigem Glühen im Temperaturbereich von 550 bis 780 °C ablaufenden Gefügeänderungen durch licht- und elektronenoptische Beobachtungen, mikrochemische und röntgenographische Untersuchungen der elektrolytisch isolierten Karbidphasen sowie Messung der Änderung der Koerzitivfeidstärke. Kennzeichnung der Gefügeausbildung durch Einordnung in Klassen und Darstellung in Temperatur-Zeit-Schaubildern.  相似文献   
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