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101.
p22312jg76168426/xxlarge8220.gif" alt="ldquo" align="MIDDLE" BORDER="0">Good genesp22312jg76168426/xxlarge8221.gif" alt="rdquo" align="MIDDLE" BORDER="0"> are genetic elements that contribute to lifetime reproductive success, regardless of an individualp22312jg76168426/xxlarge8217.gif" alt="rsquo" align="BASELINE" BORDER="0">s additional genotype. Their existence is debated, and most work has targeted their viability benefits to the offspring of choosy females. In the present study, we analyze a case of potential good genes effects in adult male sand lizards (Lacerta agilis). We show that males with a particular RFLP (Restriction Fragment Length Polymorphism) MHC genotype (O-males), as opposed to those that lack this genetic element (NO-males), have less ectoparasites under increasing physiological stress (indexed by baseline corticosterone level), and are not constrained by parasites at production of status coloration. Furthermore, O-males are more successful at mate acquisition and guard their partners longer. Ultimately, they have a higher genetic reproductive success as assigned by microsatellites.Communicated by W. Cooper  相似文献   
102.
Degradation of the herbicide imazapyr by Fenton reactions   总被引:4,自引:0,他引:4  
The degradation of the herbicide imazapyr has been carried out by three advanced oxidation processes involving iron ions as catalysts: Fentonp11821rx1/xxlarge8217.gif" alt="rsquo" align="BASELINE" BORDER="0">s reagent, photo-Fenton and electro-Fenton. We show that all processes are rapid and efficient. The kinetic rate constant was found to be k=5.4×10p>9p> Mp>–1p> sp>–1p>. The mineralization of imazapyr is almost complete using the photo-Fenton and electro-Fenton processes.  相似文献   
103.
This study was conducted to evaluate cyhalofopp‐butyl mobility in a sandy loam soil and subsequent distribution of residues at various depths under field conditions. Soil samples were taken from 0 to 150 cm depths at 3–90 d after rains in lysemeter of 1 and 2 m depths. Cyhalofopp‐butyl application at two rates and subsequent precipitation had a significant impact on soil, physico‐chemical properties and herbicide mobility. Precipitation caused substantial mobility of cyhalofopp‐butyl in the soil and 1.1–7.6 μg Lp>?1p> of cyhalofopp‐butyl was found in leachates. Cyhalofopp‐butyl residues in the leachates were probably due to preferential flow through the soil. Cyhalofopp‐butyl residues were detected in significant amounts from the soil up to 10 d, later, residues were found below the detection limit but its three transformation products viz., cyhalofop acid, diacid, and phenol were detected.  相似文献   
104.
催化氧化法处理对硝基酚钠生产废水的研究   总被引:3,自引:0,他引:3  
研究了催化氧化法处理对硝基酚钠生产废水的工艺参数,COD去除率可达90%,探讨了从酚钠母注人中盐析酚的条件,回收量为15.86Kg酚钠/m^3废液,提出了综合治理酚钠废水的工艺流程。  相似文献   
105.
Deletion of the distal end of the short arm of chromosome 1 (1p36) is thought to be a common terminal chromosomal deletion. However, few cases prospectively diagnosed prenatally have been reported. In this case, prenatal ultrasound at 21 weeks of gestation noted the fetus to have mild ventriculomegaly (Vhanterior = 11 mm and Vhposterior = 12 mm) and increased nuchal edema (6 mm). Maternal serum α-fetoprotein was normal unlike in a majority of previously described cases. The prenatal ultrasound features were further clarified with fetal MRI. Chromosome analysis following amniocentesis demonstrated a 1p36 deletion, which was confirmed by fluorescence in situ hybridization (FISH). The syndrome associated with 1p36 deletion is well described in infants and is characterized by typical facial features (prominent forehead, straight eyebrows. deep-set eyes, flat nasal bridge and a pointed chin). Other associated features are neurodevelopmental delay, seizures, cardiomyopathy and neurosensory hearing impairment. This case supplements our knowledge of the prenatal features of 1p36. Identification of this deletion by direct chromosomal analysis can be technically difficult and vigilance is required to improve diagnosis. FISH analysis is an important diagnostic adjunct where the diagnosis is suspected following classical G-banding techniques. However, in this chromosomal anomaly there remain few characteristic prenatal signs that are readily diagnosed with prenatal imaging. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   
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108.
IntroductionLindane ,p,p’ DDTandHCBaresemivolatileandlipophilic ,andtheyfallintotheclassofcompoundsdescribedaspersistentorganicpollutants.Moreover,thesecompoundshavebeenidentifiedaspotentendocrinedisrupters(Smith ,2 0 0 2 ;Willett,1 998;Robert,2 0 0 1 ) .Ithasbeenreportedchlorinatedorganiccompoundscanbedecomposedveryslowlyinsedimentsthroughvariousreactions(Niesl,1 990 ) .Factorsinfluencingthebiodegradationofcompoundsarevarious.Amongthem ,itwasreportedthattheeffectsofnaturalorganicmatters…  相似文献   
109.
This article investigates available environmental data from measurements of the everywhere present contaminants polychlorinated dibenzo‐p‐dioxins and dibenzofurans (PCDD/F) in dated trends in sediment, soil and herbage from locales in Europe and North America. The PCDD/F data are examined in relation to potential major PCDD/F sources based on volume: wood and coal, example of natural combustion; pentachlorophenol (PnCP), example of chlorinated aro‐matics; and polyvinyl chloride (PVC) pyrolysis, example of chlorinated aliphatic. Collected PCDD/F data of congener sums and 2, 3, 7, 8‐substituted congener (PCDD/F profiles) have been investigated with multivariate methods: principal component analysis (PCA) and partial least squares projection to latent structures model (PLS). The results show that PCDD/F data from 12 locales can be separated in one to three independent profiles. Normally one profile is related to the PCDD/F found in PnCP and another to combustion. A subtype of the ‘PnCP’ and ‘combustion’ profiles indicates PCDD/F contributions from PVC‐related combustions. The environmental profiles exhibit some differences from the suggested sources. The relatively unprotected PCDD/F related to PnCP is suggested to have passed photolytic and/or thermal dechlorinations. Lower‐chlorinated congeners in environmental profiles related to combustion appear to have been influenced by environmental distribution processes. PCDD/F data before industrial production of chlorinated organics have only limited similarity to PCDD/F in technical PnCP profiles; an average 4.6% of the PCDD/F is related to PnCP. This suggests that PnCP similarity in recent deposition profiles cannot be a result of environmental transformation. The average proportion of PnCP‐related PCDD/F profile in recent depositions is 35% with North America high (average 57%) and Europe low (average 24%).  相似文献   
110.
Soil and sediments collected at a former chlor‐alkali plant in coastal Georgia (United States), revealed the presence of PCDF concentrations as great as 82.3 ng/g, dry wt. PCDF congener profile in soil was typical of “chlorine pattern”; with elevated proportions of OCDF and HpCDF. Concentrations of PCDFs declined gradually by 44‐fold at a distance of about 500 m along the contamination gradient. Of PCDDs/DFs, 2,3,7,8‐substituted PCDFs accounted for 94–98% of the TCDD‐like activity, which declined by 25‐fold, corresponding with the reduction of total PCDF concentrations. Concentrations of PCDDs in sediments were as great as 17 ng/g, with an elevated contribution from OCDD. The magnitude of decline in PCDD concentrations with distance from the source was less pronounced than that for PCDFs. PBDDs and PBDFs were not detected. Polybrominated biphenyl ether (PBBE) and monobromo‐heptachloro dibenzo‐p‐dioxins and dibenzofurans (PXDDs/DFs) were found, though, at low concentrations. Their spatial distribution was similar to those of PCDDs.  相似文献   
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