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The changes of immunoglobulin-G and creatinine levels in mid-altitude were investigated in rabbits. The animals living at sea level were exposed to 2240 m altitude for 22 days period. When compared with sea level values; immunoglobulin-G levels were significantly low. Serum creatinine level decreased significantly in the 2nd day, then reached the sea level amount on the 12th day. On the 22nd day a significant increase was observed. It was concluded that the decrease in immunoglobulin-G values may be due to the depression of protein synthesis. The increase in plasma creatinine level would be explained by the decrease in urine.  相似文献   
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Satellite remote sensing of wetlands   总被引:20,自引:0,他引:20  
To conserve and manage wetland resources, it is important to inventoryand monitor wetlands and their adjacent uplands. Satellite remote sensing hasseveral advantages for monitoring wetland resources, especially for largegeographic areas. This review summarizes the literature on satellite remotesensing of wetlands, including what classification techniques were mostsuccessful in identifying wetlands and separating them from other land covertypes. All types of wetlands have been studied with satellite remote sensing.Landsat MSS, Landsat TM, and SPOT are the major satellite systems that have beenused to study wetlands; other systems are NOAA AVHRR, IRS-1B LISS-II and radarsystems, including JERS-1, ERS-1 and RADARSAT. Early work with satellite imageryused visual interpretation for classification. The most commonly used computerclassification method to map wetlands is unsupervised classification orclustering. Maximum likelihood is the most common supervised classificationmethod. Wetland classification is difficult because of spectral confusion withother landcover classes and among different types of wetlands. However,multi-temporal data usually improves the classification of wetlands, as doesancillary data such as soil data, elevation or topography data. Classifiedsatellite imagery and maps derived from aerial photography have been comparedwith the conclusion that they offer different but complimentary information.Change detection studies have taken advantage of the repeat coverage andarchival data available with satellite remote sensing. Detailed wetland maps canbe updated using satellite imagery. Given the spatial resolution of satelliteremote sensing systems, fuzzy classification, subpixel classification, spectralmixture analysis, and mixtures estimation may provide more detailed informationon wetlands. A layered, hybrid or rule-based approach may give better resultsthan more traditional methods. The combination of radar and optical data providethe most promise for improving wetland classification.  相似文献   
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The precise clinical manifestations of tuberculosis are likely to result from a complex interaction between the host and the pathogen. We took serum samples from a group of patients with a variety of clinical and radiological stages of pulmonary tuberculosis in order to characterize tumor necrosis factor-alpha (TNF-alpha), interleukin-4 (IL-4) and soluble interleukin-2 receptor (sIL-2R) response. We further evaluated whether the levels of TNF-alpha, IL-4 and soluble IL-2R are related with each other, and also evaluated the levels of TNF-alpha, IL-4 and sIL-2R after anti-tuberculosis therapy and relation with radiologic scores. Forty-three inpatients with active pulmonary tuberculosis and 19 healthy controls participated in the study. Patients were divided into four categories radiologically on chest X-ray (minimal, moderate-advanced, far-advanced and with miliary infiltration). Concentrations of TNF-alpha (20.9+/-10/15.4+/-8 pg/ml) and sIL-2R (2569+/-842/1444+/-514 pg/ml) were statistically different between patients and controls (p=0.02 and p=0.0001, respectively). Before chemotherapy there was a positive correlation between TNF-alpha and sIL-2R (r=0.34), but there was no correlation between IL-4 and TNF-alpha, and between IL-4 and sIL-2R (r=-0.23 and r=-0.22). The TNF-alpha level was not statistically different in four groups before and after chemotherapy. Results of this study provided some evidence confirming the previously reported role of TNF-alpha, IL-4 and sIL 2R in the control of tuberculosis, but these cytokines were not found related with disease severity.  相似文献   
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1. The effects of mid-altitude on the profiles of total serum lipid, cholesterol, fibrinogen, albumin, Ca2+, Cl-, Na+ and K+ were investigated in rabbits for 22 days. From 30 rabbits living at sea level 15 were exposed to 1170 m and 15 to 2240 m altitude. 2. When compared with sea level values; total protein, albumin and K+ significantly decreased up to 5th day (P less than 0.01), then they gradually increased. 3. Total lipid, cholesterol, Ca2+, Cl- and Na+ levels elevated in 2nd day (P less than 0.01) then they gradually decreased to their sea-level values. 4. It was concluded that the adaptation mechanisms begin at mid-altitudes.  相似文献   
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