First-trimester biochemical and molecular diagnoses using chorionic villi: High accuracy in the U.S. collaborative study

The accuracy of biochemical and molecular prenatal diagnoses using chorionic villi as the fetal source was assessed by seven centres participating in the NICHD collaborative study on the safety and accuracy of chorionic villus sampling (CVS) and amniocentesis. Of 601 pregnancies studied, biochemical methods were used to determine the diagnosis in 283 fetuses at risk for 35 different metabolic disorders. Fifteen different lysosomal storage diseases accounted for 81 per cent of the biochemical prenatal diagnoses performed, with 57 per cent of these pregnancies at risk for Tay-Sachs disease. No errors were made in the biochemical diagnoses that predicted affected or unaffected fetuses. However, the diagnoses of certain disorders (e.g., mucopolysacchariodosis type IH, metachromatic leukodystrophy, and Krabbe disease) occasionally required confirmatory studies in cultured amniocytes because the enzyme results were inconclusive in direct and/or cultured villi or due to the presence of a pseudodeficiency allele. Of these, only the diagnosis of a fetus at risk for Krabbe disease remained inconclusive after special studies to discriminate between mutant and pseudodeficiency alleles. Recombinant DNA techniques were used to predict the diagnosis of 318 fetuses at risk for 16 different disorders in which the defective disease gene could be detected either directly or by linkage analysis to a nearby polymorphic marker. Of these, 32 per cent were for haemoglobinopathies, 25 per cent for cystic fibrosis, 24 per cent for Duchenne or Becker muscular dystrophy, and 7 per cent for haemophilias. Pregnancies at risk for known disorders with specific molecular lesions (e.g., sickle cell disease) were accurately diagnosed in direct and/or cultured villi. Diagnoses requiring analyses with closely linked polymorphic markers were occasionally uninformative or inconclusive. Maternal contamination was not reported in any biochemical or molecular-based diagnosis. These studies document the high accuracy and rapidity of both biochemical and mutation-specific prenatal diagnoses with direct and cultured chorionic villi.     

Effect of applying selenium fertilizer to improve soil and increase selenium level in food for prevention and treatment of Kaschin-Beck disease

For prevention and treatment of Kaschin-Beck disease by applying Se fertilizer to soil to increase Se up to normal level for the wheat grains is introduced in this paper. After use this measure the intake of Se by the residents in the exemplary area increased from 10.4μg to 33.6 μg per day in average. After supplementing Se to human body one year, there is no new patient found among 300 healthy children in the exemplary area but 4 patients found among 264 healthy children in the control area. It is shown that by applying Se fertilizer to KBD area is a effective way for preventing and cure this disease.     

Prenatal diagnosis of autosomal dominant polycystic kidney disease using flanking DNA markers and the polymerase chain reaction

A prenatal diagnosis was carried out on a 9-week-old fetus at risk for autosomal dominant polycystic kidney disease (ADPKD). Ten members of the family were previously typed using five DNA markers linked to the PKD1 locus on chromosome 16, and one marker linked to the putative PKD2 locus on chromosome 2. The polymerase chain reaction (PCR) was used to amplify the D16S125 locus. Pairwise and multipoint lod scores indicated that the family was most likely segregating a PKD1 mutation. The fetus inherited the disease haplotype from the affected parent. Diagnostic accuracy was greater than 99 per cent, taking into account the possibility of genetic heterogeneity.     

Mercury pollution and control in China

Before 1970s the Second Songhua River and Ji Canal of China had been polluted seriously by mercury. During peak pollution period, mercury levels in water, sediment and fish body of these rivers were close to or even higher than that of famous Minamata Bay of Japan. Some residents who live near to the polluted rivers were affected and the methyl mercury values in their blood, hair and urine were higher than normal people obviously . Since the fish had decreased even vanished in these rivers, so the food chain that transfers mercury to human also was out off almostly. However, nervous symptoms of Minamata disease were discovered among fisherman who had eaten more fishes. This report relates the stories about the mercury pollution of the Second Songhua River and Ji Canal.     

Study on correlation between humic acid and selenium in Kaschin-Beck disease areas

The relationship between humic acid and selenium content was studied in this research. The results of calculation showed that there is more humic acid and less selenium in Kaschin-Beck disease areas in China. Fulvic acid in soil could increase selenium level in plants. The chemical bonding between humic acid and selenium was observed with an I.R. spectroscope. It was remarkable for the changes of absorption peak and frequency in 1100-1000 cm-1, 900-700 cm-1.     

Measurement of fetal urine production in mild infantile polycystic kidney disease—A case report

It is generally recognized that the sonographic findings of infantile polycystic kidney disease (IPKD) are bilaterally enlarged kidneys, oligohydramnios, an absent fetal bladder, and the typical kidney texture. Since there is a broad spectrum of renal compromise with IPKD, in utero diagnosis is thought to be limited to the severe forms. This paper reports a mild case of IPKD, where the in utero diagnosis was established by measuring fetal urine production and amniotic fluid volume serially during pregnancy, and by ultrasonographic examination of fetal kidneys.     

降尘促进酸雨对土壤——蔬菜的效应

酸尘降地区酸雨难在短期内单独致使水体和土壤酸化。降尘对土壤－－蔬菜中的ＳＯ４＾２－、ＮＯ３＾－、Ｃａ＾２＋和Ｈｇ有较大贡献。随着降尘量的增加，对应土壤中的全Ｓ、吸附态Ｓ和Ｈｇ含量也相应增加，表现出高度下相关，但未达显著水平；ＮＯ３表现为中度相关，Ｃａ＾２＋表现为弱相关。降尘土促进酸寸对蔬菜的危害，主要表现多病害，且伴有虫害发生，蔬菜宜种度变窄，对酸沉降敏感的青菜、蕃茄等几乎绝种。钙质土对降尘和酸雨     

沈阳大气污染物与气象因素对呼吸疾病门诊数的影响

利用时间序列的半参数广义相加模型,分析沈阳市2015年12月~2016年12月整个观测期间和污染期间大气污染物与气象因素及其交互作用对呼吸系统疾病门诊就诊人数的影响.结果表明：无论是全人群、不同性别、还是不同年龄人群中,HONO对门诊人数的影响均非常显著.最佳滞后时间下,PM₁₀、PM_2.5、SO₂、NO₂、HONO和NH₃的浓度每增加10μg/m³或1个IQR,对应的呼吸系统疾病日门诊人数增加百分比（ER）分别为1.29%（1.18%~1.4%）,1.31%（1.2%~1.43%）,3.28%（3.07%~3.50%）,5.26%（4.91%~5.61%）,12.89%（4.45%~22.01%）和11.09%（9.84%~12.36%）.HONO、NH₃和PM_2.5对女性的影响远比对男性的影响大,污染日当日对门诊量的影响最大;PM_2.5对≥65岁的老人影响大;NH₃、HONO和SO₂对15~65岁人群影响大.污染天气条件下HONO和NO₂对门诊人数影响最高,均为污染日当日对门诊量的影响最大.沙尘天气Ca²⁺等土壤性离子影响最大.多污染物模型中,不同污染物对呼吸疾病的影响具有协同作用或拮抗作用.气温对各呼吸疾病的影响最强,低温和高污染物浓度对呼吸系统疾病门诊人数的影响有交互作用.     

RS在森林病虫害监测研究中的应用

森林病虫害是影响森林健康的主要因素之一。森林病虫害的快速准确监测、检测及其损害评估无论对森林经营者还是生态学家都具有重要意义。在大的空间尺度上，遥感数据早已被广泛有效地用于检测森林病虫害所引起的失叶现象。目前，在森林病虫害的遥感监测方面所利用的遥感数据主要有Landsat TM,MSS和SPOT HRV等卫星遥感数据和多种航空遥感数据；此外，各种地面辅助地理散据和野外调查数据可以提高对森林病虫害的监测精度。不同类型的森林往往感染不同的森林病虫害，而不同的森林病虫害所引起的森林受损症状不同，有的病虫害导致森林反射光谱的显著变化，有的则导致森林大量失叶。因此，对不同病虫害的遥感监测方法不同。随着技术的进步，传统的图像增强、图像分类和影像差等病虫害监测技术已显粗糙。近年来，更多、更复杂的图像处理方法被广泛用于检测病虫害引起的森林变化，各种数学方法和GIS技术也为病虫害的遥感监测提供了新的活力。虽然森林病虫害的遥感监测面临挑战，但随着计算机软硬件技术和遥感技术的进步，森林病虫害的遥感检测依然具有广阔的发展空间。     

民用建筑中的公共卫生安全问题研究

在对历史上所发生的几次传染病流行为进行分析的基础上 ,笔者认为 :传染病的流行 ,对人类的生存与发展会产生非常重要的影响 ;人一生中大部分时间是在室内度过 ,因而人类传染病的流行与建筑物及其环境有关 ;传染病流行的关键包括 3个要素 ,其中传染途径与建筑物的关系更为突出。通过对已有建筑物的考察 ,发现建筑物内水与空气的处理不当可能是传染病的重要传染途径 ,为此分析了成因 ,同时提出了处理传染途径的具体措施。