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981.
IntroductionCleanerproduction (CP)holdsgreatpromiseasaneffectivestrategyinthefaceofdoublechallengesofenvironmentalprotectionandeconomicdevelopment.In 1993,ademonstrationproject (B 4project) ,designedandexecutedbytheStateEnvironmentalProtectionAdministration (…  相似文献   
982.
含铬废渣的综合利用   总被引:18,自引:0,他引:18  
着重介绍了重庆东风化工厂铬渣综合治理的成效。其中包括该厂已成功应用于工业化生产的铬渣作玻璃着色剂,钙镁磷肥助熔剂,炼铁烧结熔剂等利用途径及其还原解毒机理,以及在水泥等建材方面的应用尝试。  相似文献   
983.
Fluid from pleural effusion (n=2) and cystic hygroma (n=7) was obtained from eight fetuses, between 13 and 32 weeks of pregnancy at the time when a conventional prenatal diagnosis procedure was carried out. As these fluids contain lymphocytes, they were processed like peripheral blood. A karyotype was obtained in 4 days in both cases of pleural effusion and in four out of seven samples of cystic hygroma. An abnormal karyotype was detected in three of the four samples of cystic hygroma: two trisomies 21 and a monosomy X. Different parameters were evaluated in order to predict the feasibility of obtaining a cytogenetic diagnosis. Our data showed that if the amount of fluid obtained was ⩾4 ml and the initial lymphocyte count (ILC) was >0.2 × 106 cells/ml, a cytogenetic diagnosis was possible from an initial concentration of cultured lymphocytes )ICCL) of >0.06 × 106 cells/ml.  相似文献   
984.
We describe molecular prenatal diagnosis and carrier detection of tyrosinase-negative oculocutaneous albinism (OCA1A) in two families. In one family, we carried out DNA-based prenatal diagnosis of OCA1A. In the other family, mutation analysis and carrier detection obviated the need for prenatal diagnosis. Molecular analysis is safer and probably more accurate than fetoscopy and fetal scalp biopsy, and should become the method of first choice for prenatal diagnosis of OCA1.  相似文献   
985.
In this paper we describe the use of five-colour fluorescence in situ hybridization for prenatal diagnosis of aneuploidy using uncultured amniotic fluid cells. The analysis is based on ratio mixing of dual-labelled probes and digital imaging for the detection and visualization of five different probes specific for the five target chromosomes, 13, 18, 21, X, and Y. A retrospective blind analysis of 30 coded uncultured amniotic fluid samples correctly detected fetal sex and five trisomy 21 cases. Multicolour fluorescence in situ hybridization used in this way allows rapid and simultaneous detection of the most frequent aneuploidies.  相似文献   
986.
This study was undertaken to evaluate the relationship between maternal serum alpha-fetoprotein (MSAFP) levels and oesophageal atresia (OA). OA occurred in 16 fetuses of mothers who had an MSAFP test in the study interval. The multiple of the median (MOM) value for MSAFP averaged 1·54 ± 0·65 (range 0·5–2·9 MOM), which was significantly higher than the value seen in controls. The median MOM was 1·35. Using a cut-off of 2·5 MOM, the sensitivity of MSAFP for detecting OA was 19 per cent. Although OA should be considered in the differential diagnosis of an elevated MSAFP level, MSAFP cannot be considered an appropriate screening test for OA given the low sensitivity.  相似文献   
987.
利用微生物进行煤炭脱硫   总被引:11,自引:0,他引:11  
从松藻煤矿分离到的氧化亚铁硫杆菌(Thiobacillus ferrooxidans)菌株T-4,能够利用煤炭中的黄铁矿作为能源基质,用含有细胞量10~8-10~9个/ml,pH1.55-1.70的种菌液,脱除煤炭中的无机硫,并进行了细菌煤炭脱硫的条件试验,9个样品4—72h试验结果,总硫量由1.31—2.45%降至1.05—1.88%,黄铁矿硫脱除率达86.11—95.16%.  相似文献   
988.
In 19 pregnancies at risk for 21-hydroxylase deficiency (21OHD) in 18 families with at lea one affected child, prenatal diagnosis was performed by RFLP analysis using the enzymi Taq I and EcoRI and the DNA probes specific for the 21 OH genes, the closely linke complement C4 genes and the highly polymorphic HLA class II genes DRB, DQB, and DPI For fetal DNA analysis either chorionic villi or cultivated amniotic cells were used. In all 1 cases, a clear prenatal diagnosis was possible either with the 21OH probe alone or in mo cases, by combining the results of the different closely linked loci.  相似文献   
989.
研究了用气敏电极测定焦化厂废水中氨的分析方法,对测定的线性范围,响应时间、回收率、干扰物质等作了理论探讨和大量试验。在pH为115~140时,线性范围为100×10-5~100×10-1mol/L,最低检出限为50×10-6mol/L,RSD≤25%。  相似文献   
990.
序列间歇式好氧活性污泥法处理生物制药废水研究   总被引:7,自引:0,他引:7  
本研究采用好氧SBR法处理生物制药废水。试验结果表明,废水中不需另加氮磷营养物质,当进水CODCr为911~3280mg/L时,在曝气16h条件下,出水CODCr在350mg/L以下,BOD5在80mg/L以下,SS在150mg/L以下,皆达到生物制药工业废水二级排放标准。本文还对好氧SBR法的有机物降解动力学过程进行了研究。  相似文献   
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