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971.
HLA-DQA1 typing of 227 randomly selected Northern Italian people by the use of polymerase chain reaction are reported. The combined use of commercial Amplitype HLA-DQalpha system and four sequence-specific oligonucleotide probes allows the definition of 8 alleles and 36 genotypes, arranged according to World Health Organisation nomenclature. Seven of these genotypes are not observed among the analyzed samples. Allele frequencies range from 1.5 to 35.7% and genotype observations do not deviate significantly from Hardy-Weinberg equilibrium; observed heterozygosity is 0.8238 with an allelic diversity value of 0.79 and the power of discrimination is 0.925. Our Italian population sample shows differences from other Caucasian samples both for allele and genotype frequencies. This locus typing for the 8 defined alleles provides a rapid and sensitive method in individual identification and paternity investigation.  相似文献   
972.
The US has been reluctant to acknowledge Russia's relevance to the Asia‐Pacific, the author says, because “too little time has passed since the interests of these two former adversaries collided in the region.” Russia has the longest Pacific coastline and borders with China, Japan, Korea and Mongolia. Despite the end of the Cold War, however, Russia is still not an integrated participant in Northeast Asian economic cooperation. Vladimir Ivanov is a Visiting Fellow at the Economic Research Institute for Northeast Asia in Niigata. He argues that Russia has made a clear choice between “guns and growth,” and that the country should be allowed to come in from the cold and join this region's development.  相似文献   
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应用在鸭胚成纤维细胞上连续传代的方法 ,获得了由雏鹅新型病毒性肠炎病毒强毒株(NGVEV CN株 )致弱的弱毒株 (CN4 0 株 )。该弱毒株TCID50 为 10 - 8.0 83,具有良好的安全性和稳定性 ,在易感 1日龄雏鹅连传 8代不返强。该弱毒具有良好的免疫原性 ,最小免疫剂量为 10 0 0 0TCID50 ,免疫后 3d产生部分免疫力 ,5d产生坚强免疫力。口服免疫效果最好 ,对雏鹅免疫期在30d以上。该弱毒株能够干扰强毒在雏鹅体内繁殖 ,进入鹅体后能够进行一定程度繁殖并排泄出体外 ,使同居雏鹅感染并获得一定程度免疫力。临床使用后可极显著降低雏鹅的死亡率。  相似文献   
975.
Growth rates of output and factor productivity in Soviet industry fluctuate around a long-term downward trend. These fluctuations can be partially explained by fluctuations in the growth of services of capital. The capacity utilization rate is taken as a proxy for the extent of utilization of capital stock. Variations in the capacity utilization rate explain a significant part of the changes in the rate of growth of total factor productivity between 1970–1983. Declines in the capacity utilization rate are caused by errors in the allocation of investment, which create an imbalance of capacities between raw-materials and manufacturing sectors.  相似文献   
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Gastromalacia is the acute autolytic erosion of the gastric wall. It generally occurs postmortem, and it appears as a slimy brownish black region of the wall which occurs principally in the gastric fundus. A 59‐year‐old woman died in the Emergency Department following a 2‐day period of mild abdominal pain, vomiting, and diarrhea. A forensic autopsy was performed which revealed a rupture of the gastric fundus that had caused leakage of gastric content into the abdominal cavity. There was no macroscopic evidence of peritonitis, and the stomach wall adjacent to the rupture site showed marked thinning. The gross appearance was typical of gastromalacia. In contrast, histological observations revealed the presence of an ulcer at the site of perforation and a severe acute inflammatory reaction indicating a robust reaction with an antemortem rupture.  相似文献   
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