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A result that application of sodium selenite or fly ash to some of soilin loess plateau can increase Se content in wheat grain has been demonstrated by the pot and field experiments, and added Se in soil can last its availability for 3 years. So this is a good measure for improving the low Se soils and preventing the Kaschin-Beck disease. 相似文献
23.
Trung Pham Huu Yves Dumez Claude Marquetty Anne Durandy Joëlle Boue Jacques Hakim 《黑龙江环境通报》1987,7(4):253-260
Prenatal diagnosis of chronic granulomatous disease (CGD) was performed in four male high risk fetuses. The male sex was previously determined by an amniotic cell karyotype. Three kinds of test were performed on fetal blood obtained by umbilical venous puncture under fetoscopy at the 20th gestational week: nitroblue tetrazolium reduction (NBT) cytochemical test with phorbol myristate acetate (PMA) as activator; luminol enhanced chemiluminescence with activation by serum opsonized zymosan (STZ) or PMA; superoxide anion (0) production by measurement of the superoxide dismutase inhibitable reduction of cytochrome c with PMA as activator. Results were compared to those obtained in six fetuses investigated for other inherited diseases. In one case, absence of granulocyte defects was confirmed at birth. In three other cases, the tests showed deficient metabolic oxidative granulocytes. The pregnancy was terminated and the CGD diagnosis was confirmed on the products of abortion. The use of three different techniques performed on whole blood for CGD prenatal diagnosis is recommended instead of a single isolated test to ensure a higher confidence in the diagnosis. 相似文献
24.
Isabella Delaroche Margherita Sabani Giuseppe Calabrese Rita Mingarelli Giandomenico Palka Professor Bruno Dallapiccola 《黑龙江环境通报》1995,15(3):278-281
An apparently balanced t(2q;21q) translocation was discovered in fetal blood and amniocytes of a 22-week fetus, monitored because of ultrasonographic evidence of a heart disease. FISH (fluorescence in situ hybridization) analysis disclosed a complex translocation between chromosomes 2q, 18q, and 21q, which was inherited from the healthy mother. This observation corroborates the usefulness of molecular cytogenetic techniques in raising the quality of prenatal diagnosis and detecting subtle rearrangements not resolved by standard cytogenetics. 相似文献
25.
Epidemiological survey of 573 families, clinical examination of 2593 persons, and X-ray examination of 1136 persons (in 16 typical endemic villages) were conducted, based on the classification of endemiology for KBD disease areas, i.e, mountain type, loess plateau type, plateau type, and flatlands type. It was revealed that the KBD disease areas exhibited the regular pattern of corming-into-being, development and passing-away and the characteristics of growth and decline. Further, it was found clinically that the disease areas may be divided into 4 types, i.e., recent onset, developing, stable, and historical. This division is simple and easy, practical, scientific, and reliable and can be applied by medical personnel at different levels. 相似文献
26.
L. Bovicelli M.D. F. M. Picchio G. Pilu G. Baccarani L. F. Orsini N. Rizzo G. Alampi P. M. Benenati J. C. Hobbins 《黑龙江环境通报》1984,4(1):67-72
In a case of fetal heart failure caused by endocardial fibroelastosis, prenatal echocardiography clearly demonstrated; a thickened endocardium. We therefore suggest that an abnormal endocardium may be detected in utero by ultrasound, thus representing an important clue in the differential diagnosis of fetal nonimmune hydrops and in the evaluation of pregnancies at risk for endocardial fibroelastosis. 相似文献
27.
Foci of calcification were observed at autopsy in the liver of a fetus with complete trisomy 9 on which two cordocenteses had been performed. It is suggested that liver calcifications are a possible complication of the procedure. As several other cases of calcifications in the liver and other organs of fetuses with autosomal trisomies have been described without a history of cordocentesis, further studies should be carried out to determine whether fetuses with chromosomal anomalies are more prone to thrombus formation and embolization. 相似文献
28.
污染生态学的新发展—污染进化生态学 总被引:4,自引:1,他引:4
污染胁迫的最显著效应是消除敏感物种或个体,导致植物居群进化。突变是进化的原料,选择是进化的手段,隔离是进化的条件,控制抗性性状的基因因物种及污染物的种类不同而异,但也会出现植物同时具有对某两种或几种污染物的抗性,即所谓协同抗性;污染除使植物衰退外,还可能导致一些遗传信息丧失,使抗性种群内物种单一,降低其适合度,对其它环境胁迫因素的抵抗力下降,即所谓适应代价。 相似文献
29.
热镀锌板表面钝化时的磷化工艺 总被引:1,自引:0,他引:1
热镀锌板表面钝化(铬酸盐钝化),主要是为了防止在使用过程中其表面被氧化。由于表面的钝化膜的存在。使得磷化工艺无法进行,从而影响涂装后涂层的附着力(铬酸盐钝化膜不如磷化膜附着性好)和耐蚀性能(铬离子不耐氯离子的腐蚀)。为了提高热镀锌板表面钝化后其表面的涂装性能,开发出一种适合上述条件的磷化工艺。 相似文献
30.