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BACKGROUND: Previous studies have suggested altered responses to repeat skin tests in the sites of IgE-mediated late-phase reactions (LPRs) induced within the previous 48 hours. To explore the possible modulation of LPRs in such rechallenge sites, we compared inflammatory responses in skin chambers induced over previous LPR and control sites. METHODS: Skin blisters were induced and unroofed in 12 human subjects over two sites of previous LPRs induced by intradermal injection of pollen antigens 24 hours or 48 hours earlier and two sites previously injected with buffer diluent (B). Skin chambers containing the same antigens were appended to one intradermal antigen site (called Ag/Ag) and one intradermal B site (B/Ag), and B-containing chambers were placed over antigen (Ag/B) and B (B/B) intradermal sites. Fluids were collected after the first and the second through fifth hours of challenge. RESULTS: In skin chamber challenges 24 hours after the intradermal injection, there was no significant difference after the first hours between the Ag/Ag or B/Ag sites in either histamine or tryptase levels; both were significantly higher than at Ag/B or B/B sites (p < 0.01). The same pattern of events was seen in fluids obtained from the second through fifth hours. The same pattern of findings was seen in examination of levels of the total leukocyte accumulation, total eosinophil accumulation, and frequency of activated (EG2+) eosinophils. Levels of lactoferrin, released from activated neutrophils, and eosinophil cationic protein, released from activated eosinophils, were also similar at Ag/Ag and B/Ag sites; both were significantly higher than at B/B sites, whereas levels at Ag/B sites were intermediate between those found at B/Ag and B/B sites. The pattern of events in skin chamber challenges 48 hours after intradermal injection was similar to that seen at 24 hours, except that levels of inflammatory mediators/cells in Ag/B sites were more intermediate between the B/Ag and B/B sites. CONCLUSION: There is no significant alteration of mediator or inflammatory cell responses after antigen rechallenge of previous LPR sites when compared with those found in antigen challenge of non-LPR sites.  相似文献   
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It will be shown in this paper that the Li diffusion in HP-Ge, used for γ-ray detectors, always introduces extra Cu. This Cu has a negative influence on the detector resolution. It originates from the Li suspension used. We suggest that the actual diffusion temperature should be kept below 300°C.  相似文献   
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The aim of our study was to validate a hip fracture risk function, composed of age and femoral neck bone mineral density (BMD). This estimate of the 1-year cumulative risk was previously developed on the basis of Dutch hip fracture incidence data and BMD in men and women. A cohort of 7046 persons (2778 men) aged 55 years and over was followed for an average of 3.8 years. The 1-year hip fracture risk estimate was calculated for each participant according to the risk function and categorized as low (<0.1%), moderate (0.1 to < 1%), or high (> or =1%). Observed first hip fracture incidence was then analyzed for each of these risk categories by age and gender. Additionally, we calculated the relative risk per standard deviation (SD) decrease in femoral neck BMD in this population. At baseline, 2360 individuals were categorized as low risk, 2567 as moderate risk, and 378 as high risk During follow-up, 110 first hip fractures were observed corresponding to an incidence rate of 4.1/1000 person-years (pyrs) (95% confidence interval 3.4-5.0). The observed incidence rate in the low risk group was 0.2/1000 pyrs (0.1-0.9), 2.7/1000 pyrs (1.8-3.9) in the moderate risk group, and 18.4/1000 pyrs (12.4-27.2) in the high risk group. Below the age of 70 years, incidence was low in all categories, and very few individuals were considered at high risk Above the age of 70 years, the observed incidence was high in the high risk group, while in the low and moderate risk groups, the incidence remained low even over 80 years of age. In women, the age-adjusted relative risk for hip fractures was 2.5 per SD decrease in femoral neck BMD (1.8-3.6), while in men this relative risk was 3.0 per SD (1.7-5.4). In conclusion, we observed a similar relation of hip fracture with femoral neck BMD in men and women and were able to predict accurately hip fracture rates over a period of almost 4 years.  相似文献   
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The continuous production of 3 to 4.5 mm NPK-granules is achieved by spraying an appropriate mixture onto recycle or reflux (undersize) product in a rotating drum. Hot air is used to evaporate the water. An extensive study was performed on an industrial granulator to evaluate mass and energy balances, to define the average residence time of the reflux-particles and to develop a model for particle growth.The average residence time was measured from tracer experiments. The mechanism of granulation follows the particle growth principle of drying and layering. Model equations developed by Nienow for a batch fluidized bed granulation were modified to predict continuous operations.The model equation defines the thickness of the coating layer in terms of the initial particle size and mass flow rate of the reflux particles, the mass flow rate of the sprayed mixture, and both the average residence time of the particles and their contact time with the spray. The resulting equation is
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This paper compares and evaluates the significance of spectral characteristics and pixel resolution of the very high spatial resolution satellite systems (VHSRS) Quickbird-2 and Ikonos-2 for automatic extraction of ancient features on one archaeological site, the antique town Sagalassos (southwest-Turkey). The evaluation of the spectral characteristics is based on a band-by-band comparison. Pixel- and object-based classification techniques are compared with visual analyses to assess the effects of different image characteristics.

The analysis reveals that Quickbird-2 is outperforming Ikonos-2 for the visual identification of ancient remains. Its augmented spatial resolution however does not necessarily result in a better automatic classification. For Sagalassos, maximum likelihood classification on Ikonos-2 gives the best results. The accuracy of automatic extraction depends on the type and characteristics of the VHSRS data, the classification method and on on-site parameters. Site characteristics appear to play a limited role in object-based extraction on Quickbird-2, but become very important on Ikonos-2.  相似文献   
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The importance of photoperiod and ambient temperature on the accumulation of cadmium in the liver and kidneys of bank voles was determined in the present study. Males and females, aged 1 month, were given 3.0 micrograms Cd ml-1 drinking water and divided into four groups according to photoperiod (16 h light/8 h dark and 8 h light/16 h dark) and ambient temperature (20 or 5 degrees C); liver and kidneys were removed for cadmium as well as copper, iron and zinc analyses at the end of 6 weeks. Bank voles exposed to 5 degrees C in both photoperiods consumed approximately 30% less water containing cadmium than those kept at 20 degrees C. However, the total accumulation of cadmium in the liver and kidneys of males and females exposed to the low temperatures was 4.3-4.8 and 2.2-3.3 times less than that in animals maintained at room temperature in the long and short photoperiod, respectively. Simultaneously, the low temperature brought about an increase in the copper concentrations in the liver (12-43%) and kidneys (47-78%), giving rise to an inverse correlation between the cadmium accumulation and the tissue copper concentration. In contrast to cadmium and copper, the concentrations of iron and zinc were affected primarily by photoperiod. These findings indicate that ambient temperature is an important determinant of cadmium retention in the bank vole. It appears that low temperature decreases tissue cadmium accumulation not only by reducing cadmium intake but also through changes in copper metabolism.  相似文献   
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Porous anodic oxide films on aluminium formed in phosphoric acid (PAA) have been characterized nondestructively by spectroscopic ellipsometry. Compared to previous studies on porous films formed in sulfuric acid, the optical behaviour of PAA films reveals new features which have been attributed to film-substrate interface roughness and optical anisotropy effects. On one hand relatively large interface roughness has been simulated by a graded index model. On the other hand, the implementation of uniaxial anisotropy in the optical model of the PAA film enables to interpret spectroscopic ellipsometry data acquired at multiple angles of incidence in terms of the morphology of the films. More specifically, accurate and physically realistic values are found for the porosity and porous film thickness. Although more difficult to interpret from the optical findings, the thickness of the barrier part of the porous film can also be estimated. The ellipsometry characterizations are confirmed by complementary TEM analysis of various films. Finally, the anisotropy exhibited by the PAA films is in line with recent theoretical predictions of the optical behaviour of arrays of parallel cylindrical capillaries in an isotropic medium proposed by other authors.  相似文献   
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Non-industrialized countries desiring to provide patent documentation and information services should seek cooperation with countries having similar backgrounds to form a regional patent documentation and information centre. This centre should supply bibliographic patent information, copies of patent documents, SDI services, state-of-the-art searches and novelty searches.A paper based patent collection is not feasible in view of the workload involved (more than 300 man-yr) and the necessary storage capacity (15 km of paper documents). Consequently microform and EDP facilities should be used whenever convenient.To provide information on patent documents of the member countries a centralized bibliographic data base and a complete collection of patent documents in microform should be established. Information on patent documents of other countries should be obtained from existing worldwide bibliographic data bases, and from search files existing elsewhere.Patent collections in microform of the most important countries should be acquired and for certain fields of high regional interest inhouse search files could be established.  相似文献   
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