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211.
Umar Ibrahim Khalil Nourani Vahid Gökçekuş Hüseyin 《Environmental science and pollution research international》2021,28(36):49663-49677
Environmental Science and Pollution Research - Accuracy in the prediction of the particulate matter (PM2.5 and PM10) concentration in the atmosphere is essential for both its monitoring and... 相似文献
212.
Environment, Development and Sustainability - The depletion of fossil fuels and the fact that fossil fuels pollute the environment accelerated the trend toward environmentally friendly energy... 相似文献
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Françoise Serville Paule Benit Pascale Saugier Mireille Vibert Ghislaine Royer Anna Pelet Michèle Chery Arnold Munnich Stanislas Lyonnet 《黑龙江环境通报》1993,13(6):435-439
X-linked hydrocephalus-stenosis of the aqueduct of Sylvius sequence (H-SAS, MIM number 307 000) is a rare genetic disorder characterized by hydrocephalus, macrocephaly, adducted thumbs, spasticity, mental retardation, and cerebral malformations. This regularly lethal condition is usually diagnosed at birth or prenatally by ultrasound, but hydrocephalus may be moderate or even undetectable on fetal ultrasound examination. Moreover, since heterozygous women are asymptomatic, carrier detection is at present impossible before the birth of an affected son. Therefore, mapping the H-SAS locus to distal Xq (Xq28) was of primary importance for genetic counselling and prenatal diagnosis. Here, we report prenatal exclusion of H-SAS with a probability of 97.6 per cent in two male fetuses with a 50 per cent a priori risk of being affected using closely linked Xq28 DNA markers. 相似文献
217.
A prospective study of maternal serum human chorionic gonadotrophin (hCG) measurement for the selection of pregnancies with an increased risk of fetal trisomy 21 was undertaken in 24 000 pregnancies from 1 January 1989 to 31 December 1990. Maternal serum was sampled at 15-18 weeks of gestation. hCG was measured in one laboratory, with one technique. This ‘hCG high level’ technique was developed for this screening. Amniocentesis was offered to each woman with a maternal serum hCG level above the cut-off. The follow-up of the pregnancies is known in 92 per cent of cases. The combination of hCG values and maternal age gave a detection efficiency of 63 per cent for trisomy 21 with rates of amniocentesis of 30 per cent for patients aged 37 years, 20 per cent for patients aged 35 or 36 years, and 5 per cent for patients under 35 years of age. Based on this prospective study, an individual risk was calculated combining the serum hCG value and maternal age. Seventy-four per cent of trisomy 13, trisomy 18, triploidy, and 5p- deletion were detected either in the same selected group of women or in combination with ultrasonography performed when hCG values were very low. The follow-up study showed that women who had high or low hCG values represented a group at high risk for fetal or perinatal death. 相似文献
218.
Vertical structure of very nearshore larval fish assemblages in a temperate rocky coast 总被引:1,自引:0,他引:1
Small-scale vertical patterns of larval distribution were studied at a very nearshore larval fish assemblage, during the spring–summer period of several years, at two depth strata (surface and bottom) using sub-surface and bottom trawls. A total of 4,589 larvae (2,016 from surface samples and 2,573 from bottom samples) belonging to 62 taxa included in 22 families were collected. Most larvae belonged to coastal species. Although inter-annual variations in larval density and diversity could be found, total larval abundance was always higher near the bottom whereas diversity was higher at the surface. A marked distinction between the structure of surface and bottom assemblages was found. Sixteen taxa explained 95% of the similarity among surface samples. Larvae which contributed most to this similarity included species like clupeiformes, sparids and serranids, and also blenniids, tripterygiids and some labrids. In the bottom samples, fewer species were present, with only six taxa, almost exclusively from species which lay demersal eggs, contributing to 95% of the similarity between samples. Larvae present at the surface were significantly smaller than at the bottom. For some of the most abundant species found at the bottom, only small larvae occurred at the surface while the whole range of sizes was present at the bottom, indicating that larvae may be completing the entire pelagic phase near the adults’ habitat. These results indicate that larval retention near the reefs probably occurs for these species, although for others dispersal seems to be the prevailing mechanism. 相似文献
219.
Karyology of the toadfish Porichthys plectrodon (Jordan and Gilbert, 1882) (Batrachoididae) from Margarita Island,Venezuela 总被引:2,自引:0,他引:2
This paper reports the results of cytogenetic analyses carried out on Porichthys plectrodon using conventional Giemsa staining, C-banding and silver staining techniques. A diploid chromosome count of 2n=44 was observed, consisting of 8 metacentric, 10 submetacentric, 6 subtelocentric and 20 acrocentric chromosomes. Differences in length made it possible to identify homologous chromosomes within the metacentric group. Constitutive heterochromatin was distributed as large pericentromeric blocks in pairs 1 and 2, while the rest of the chromosomes were marked in centromeric regions, some more conspicuously than others. One pair of small-sized acrocentric NOR-bearing chromosomes (21) was identified by the nucleolar regions located terminally on their short arms.Communicated by P.W. Sammarco, Chauvin 相似文献
220.
Treatment of pharmaceutical wastewater containing antibiotics by O3 and O3/H2O2 processes 总被引:15,自引:0,他引:15
Ozonation of three different synthetic pharmaceutical formulation wastewater containing two human antibiotics and a veterinary antibiotic has been studied to enhance the their biodegradability. The effects of pH and initial chemical oxygen demand (COD) value as well as addition of hydrogen peroxide on ozonation process were investigated. Total organic carbon (TOC), COD, biochemical oxygen demand (BOD), and aromatic content (UV254) were the parameters followed to evaluate the performance of ozonation process. Comparison of the biodegradability of selected wastewaters containing different antibiotics confirmed that the variation of biodegradability was associated with the target compound. While BOD5/COD ratio of veterinary antibiotic formulation wastewater was increased from 0.077 to 0.38 with an applied ozone dosage of 2.96 g/l, this ratio for human antibiotic I and human antibiotic II was increased from 0 to 0.1 and 0.27 respectively. Moreover the results of this investigation showed that the ozonation process is capable of achieving high levels of COD and aromaticity removals at about their natural pH values. 相似文献