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21.
冻干水痘减毒活疫苗最小免疫剂量的研究 总被引:2,自引:0,他引:2
通过临床研究确定冻干水痘减毒活疫苗的最小免疫剂量 ,为制定规程中的免疫剂量提供科学依据。观察对象接种不同免疫剂量的冻干水痘减毒活疫苗后 ,于接种前和接种后 6周采血 ,采用荧光抗膜抗体 (FAMA)法检测其抗体阳转率和几何平均滴度 (GMT)。接种不同免疫剂量的疫苗 ,抗体阳转率差异无显著的统计学意义。疫苗中抗原含量在 2 5 0 0 0PFU/ml和 2 0 0 0PFU/ml之间 ,GMT差异无显著的统计学意义 ,但 2 5 0 0 0PFU/ml、2 0 0 0PFU/ml与 2 0 0PFU/ml之间抗体GMT的差异有极显著的统计学意义。研究结果表明 ,2 0 0 0PFU/ml为冻干水痘减毒活疫苗的最小免疫剂量。 相似文献
22.
用紫外分光度法直接溯定复方卡托普利片中氢氯噻嗪的含量及均匀度。测定波长为272±1nm,平均回收率100.2%,变异系数0.3%,吸收度与氢氯噻嗪的浓度在1~10μg/ml 范围内具有线性关系。 相似文献
23.
Genomic in situ hybridization (GISH) successfully differentiated homoeologous genomes in the interspecific hybrid Allium cepa × fistulosum, thus allowing the detection of reciprocal crossover events as label exchanges in separating anaphase I chromosomes. Three of the eight chromosome pairs were positively identified by fluorescence in situ hybridization (FISH) to rDNA sequences. There was a general similarity of the GISH-based label exchange frequencies and metaphase I chiasma frequencies, but with a 20% deficit of chiasmata. Reasons for this apparent deficit are discussed. The locations of chiasmata and label exchanges are in broad agreement. 相似文献
24.
25.
对“红包”现象的深层思考 总被引:1,自引:1,他引:0
本文试将“红包”现象由表及里的进行剖晰.(1)红包现象林林总总,从3点着笔.①红包之“风乍起,吹皱一池春水”;②红包类别、特性;③医患复杂心态(各7种).(2)红包现象的危害;(3)红包的综合治理“八抓”(抓教育,正向导廉;抓道德,自律清廉;抓制度,规范保廉;抓案例,褒贬倡廉;抓经常,时时冷廉;抓监督,约束促廉;抓评价,准绳测廉;抓支部,牢牢固廉). 相似文献
26.
Summary The purpose of this study was to characterize the pharmacokinetics of vancomycin and to develop optimal dosage guidelines in infants. Thirteen infants between the ages of 13 to 183 days were enrolled. All had been born prematurely, and average gestational age, postconceptional age, and actual body weight were 29.8 weeks, 38.2 weeks, and 2.1 kg respectively. Multiple blood samples were obtained from each patient after 72 h of therapy. Serum inhibitory and bactericidal titres were determined for peak and trough samples.There were good correlations between total body clearance of vancomycin and both postconceptional age (r=0.86) and actual body weight (r=0.87). This information was used to develop vancomycin dosage guidelines in premature infants. The regression line for vancomycin daily dosage requirements vs postconceptional age may be useful for determining initial dosage recommendations.There were also good correlations between vancomycin serum concentrations and serum inhibitory and cidal titres. Peak and trough concentrations in the therapeutic range (peak, 25–35 µg/ml; trough, 5–10 µg/ml) corresponded to titres of 1:8 and 1:2 to 1:8 respectively.Based on these data we suggest the following dosage guidelines for vancomycin: 10 mg/kg 12 hourly for 30–34 weeks postconceptional age and <1.2 kg actual body weight; 10 mg/kg 8 hourly for 30–42 weeks postconceptional age and >1.2 kg actual body weight; 10 mg/kg 6 hourly for >42 weeks postconceptional age and >2.0 kg actual body weight.Thus, doses which are lower than currently recommended are needed for infants born prematurely. Furthermore, the initial dose of vancomycin can easily be determined using an infant's postconceptional age.SML was a Fellow at Children's Hospital at the time of study and is now at Rutgers University, College of Pharmacy, Piscataway, NJ, USA 相似文献
27.
Over the past 100 years Drosophila has been developed into an outstanding model system for the study of evolutionary processes. A fascinating aspect of evolution
is the differentiation of sex chromosomes. Organisms with highly differentiated sex chromosomes, such as the mammalian X and
Y, must compensate for the imbalance in gene dosage that this creates. The need to adjust the expression of sex-linked genes
is a potent force driving the rise of regulatory mechanisms that act on an entire chromosome. This review will contrast the
process of dosage compensation in Drosophila with the divergent strategies adopted by other model organisms. While the machinery of sex chromosome compensation is different
in each instance, all share the ability to direct chromatin modifications to an entire chromosome. This review will also explore
the idea that chromosome-targeting systems are sometimes adapted for other purposes. This appears the likely source of a chromosome-wide
targeting system displayed by the Drosophila fourth chromosome. 相似文献
28.
Yongchuan Chai Yu Wang Hua Qian Bo Yang Chao Wu Jiusheng Chu Tao Yang 《American journal of medical genetics. Part A》2019,179(2):243-248
Waardenburg syndrome (WS) is a genetic disorder characterized by hearing loss and pigmentary abnormalities with variable penetrance. Though heterozygous mutations in MITF are a major cause for Waardenburg syndrome type 2 (WS2), homozygous mutations in this gene and the associated phenotype have been rarely characterized. In this study, we identified a novel p.R223H mutation in MITF in a Chinese Han family with variable WS features. Both parents carried a heterozygous p.R223H mutation. They had normal hearing, and premature greying of the hair is their only pigmentary abnormality. In contrast, their two children both carried a homozygous p.R223H mutation and had classic WS features including profound hearing loss, heterochromia irides and marked pigmentary abnormalities in hair and skin. Interestingly, the two affected children also have persistent chronic constipation since the neonatal period, symptoms suggestive of Waardenburg syndrome type 4 (WS4). Our study revealed a likely association between homozygous mutations in MITF and WS4, which implies a dosage effect for the underlying pathogenesis mechanism. 相似文献
29.
The Charcot-Mane-Tooth disease type 1A (CMTlA) phenotype is most often associated with a 1.5 megabase (mb), tandem duplication of chromosome 17 band p12 (17˜12). The prevailing hypothesis is that the demyelinating neuropathy results from a dosage effect of the peripheral myelin protein gene PMP22 which is included within this duplication. We present a patient with clinical and electrophysiological features ofCMTlA in whom an extra PMP22 gene resulted from a rare unbalanced translocation of 17p to the X chromosome. This finding further supports the hypothesis of gene dosage as the basis for CMTlA. More-over, this case highlights the importance of fluorescence in siiu hybridization (FISH) as an alternative molecular technique in the diagnosis of CMTlA. 相似文献
30.
刘秀珍 《生物医学工程学杂志》2007,24(6):1256-1259
为提高诊断X线机的诊断质量,促进放射防护工作的开展,根据"国际辐射单位和测量委员会"(International Commission on Radiological Units and Measurements,ICRU),"国际放射防护委员会"(International Commission on Radiation Protection,ICRP)关于辐射对人体的损害之划分标准,作者对岛津制作所90年代中期生产的XEB150L-20型500mA X线机按照国家规定的要求及有关标准,分别对辐射空气释动能率,半价层,输入量重复性,输出量线性,高对比分辨率,光野与照射野一致性及X线管的焦点等参数进行了测试。分析了测试的数据与结果,并进行了简要的评价。 相似文献