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941.
942.
A monoclonal antibody (AAP-1), specific for the intestinal isoenzyme of alkaline phosphatase (ALP), has been used to develop an immunoassay for amniotic fluid samples. Values in the immunoassay correlated closely with those obtained by direct determination of phenylalanine-inhibitable ALP. A panel of 124 control second-trimester amniotic fluids and 21 fluids with a 1 in 4 risk of a cystic fibrosis fetus were examined in the immunoassay. Eight of 10 affected cases had values below an arbitrary cut-off of one third median, while all the non-affected cases were above this level. Almost identical results were obtained by enzymatic determination of phenylalanine-inhibitable ALP. However, in both systems the false positive rate (control fluids with values below one third median), was unacceptably high. It is pointed out that at present the most effective system for the prenatal diagnosis of cystic fibrosis is achieved by measuring the ratio of intestinal to total ALP in amniotic fluid supernatants. This is probably best effected by enzymatic assay in the presence of phenylalanine and homoarginine inhibition.  相似文献   
943.
The symbiotic pearlfish Carapus bermudensis (Jones) demonstrates the ability, as an adult, to relocate the host sea cucumber Actinopyga agassizi in the laboratory. Host location behavior is effected unimodally with chemically mediated information of host orgin. Positive orientation of pearlfish to host “odor” does not involve chemically-elicited rheotaxis.  相似文献   
944.
Phytoplankton maximum growth rate and the saturation light intensity, Is, can be estimated from vertical profiles of primary production by non-linear least-squares estimation. Solution through the normal equations leads to formulae which are relatively simple and easy to implement. The computation of confidence contours is demonstrated, and the results are contrasted to the confidence limits on the parameters individually. These can be quite misleading due to model non-linearity and correlation between parameter estimation.The procedure has been applied to primary production data from Lake Balaton, a shallow lake in Hungary. The growth rate-temperature relation is analysed by separating the parameters into two groups characteristic for “warm” and “cold” water phytoplankton, respectively. A bell-shaped curve is found for “cold” water communities, with an optimum at about 7–9°C, whereas the “warm” water phytoplankton exhibits a strong exponential dependency in the temperature range of interest (up to 25°C). Is also appears to be related to temperature except for the “cold” water group, where Is is essentially constant. However, a roughly linear relation with considerably less scatter is obtained when Is is plotted directly versus day-averaged solar radiation. This apparent fast adaptation is attributed to the extremely short turnover time in Lake Balaton. Maximum growth rates of 10–20 d?1 have been found for temperatures between 20 and 25°C. These results and a critical appraisal of available literature suggest that the common notion of maximum growth rates being in the order of 1–3 d?1 needs revision, at least for lakes with relatively high summer temperatures.  相似文献   
945.
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Fred Van der  Veen 《Disasters》1984,8(1):13-17
Health care in a conventional war has its own characteristics. Health care in a guerilla war, as exists at present in El Salvador, adds to this some new aspects.  相似文献   
948.
Book reviews     
Frances Sharples is a terrestrial ecologist in the Environmental Science Division of the Oak Ridge National Laboratory in Oak Ridge, Tennessee, operated by Martin Marietta Energy Systems, Inc., under Contract No. DE-AC05-840R21400 with the US Department of Energy. Publication No. 3413, Environmental Sciences Division, ORNL.  相似文献   
949.
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A residential area that was formerly part of a silver factory site severely contaminated with chlorinated solvents was remediated using an in situ electro‐bioreclamation technique. Electro‐bioreclamation is a method for heating soil and groundwater combined with soil vapor and low‐yield groundwater extraction and enhanced reductive dechlorination (ERD). During the first two years of remediation in the source area (the intensive phase), a total of 80 kg of volatile organic compounds (VOCs) was removed by heating combined with ERD. After another two years of ERD in the source and plume areas (the attenuation phase), the VOC concentrations were reduced to a level below 100 μg/L in groundwater. Given these satisfying results, electro‐reclamation in combination with ERD turned out to be a successful in situ remediation technique for removing VOCs. © 2006Wiley Periodicals, Inc.  相似文献   
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