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101.
9株YONBAN相关TTV变异株全基因序列测定及其结构、分型的研究 总被引:1,自引:2,他引:1
目的:对9个TTV新分离株全基因序列测定,基因结构及基因分型的研究。方法:从9名TTV第4基因群感染阳性的婴儿血清中抽提取其DNA,用long inverted PCR扩增出全基因组,克隆和测定全基因组序列,并对测序结果进行计算机分析。结果:首次次测定了TTV第4基因群共9个新分离株的全基因序列,其中8个分离株代表核基因群首次报道的8个新基因型。结论:TTV基因组核酸序列具有高度异质性及基因型的高度多样性,但是,其独特的转录特性和基因组的基本结构在各自的基因群及基因型中十分保守。 相似文献
102.
Vivek Kapur Joanne T. Maffei Rebecca S. Greer Ling-Ling Li Gerald J. Adams James M. Musser 《Microbial pathogenesis》1994,16(6)
Virtually all clinical isolates of group A streptococci secrete a highly conserved extracellular cysteine protease that cleaves human fibronectin and vitronectin, and converts IL-1β precursor to biologically active IL-1β. Based on the high degree of gene conservation within the species and its role in host pathogenicity, it was postulated that antibodies to the cysteine protease would confer protective immunity against S. pyogenes infection. To test this hypothesis, Swiss CD1 mice were intraperitoneally administered either saline, rabbit IgG, or IgG from rabbits immunized with the protease, and challenged with a highly virulent (minimum lethal dose 10 cfu) clinical isolate of S. pyogenes expressing a heterologous cysteine protease. The results indicate that mice administered IgG from rabbits immunized with purified cysteine protease had significantly enhanced survival when compared with mice given either non-specific rabbit IgG (log rank test; χ2; p = 0.0195) or saline (log rank test; χ2; p = 0.0002). Moreover, mice actively immunized with the cysteine protease had a significantly longer time to death than the control group (log rank test; χ2; p = 0.0418). The results show that the cysteine protease elicits non-type-specific immunity to challenge with heterologous S. pyogenes. 相似文献
103.
Sequence variation of the rDNA ITS regions within and between anastomosis groups in Rhizoctonia solani 总被引:3,自引:0,他引:3
Sequence analysis of the rDNA region containing the internal transcribed spacer (ITS) regions and the 5.8s rDNA coding sequence was used to evaluate the genetic diversity of 45 isolates within and between anastomosis groups (AGs)
in Rhizoctonia solani. The 5.8s rDNA sequence was completely conserved across all the AGs examined, whereas the ITS rDNA sequence was found to be highly
variable among isolates. The sequence homology in the ITS regions was above 96% for isolates of the same subgroup, 66 – 100%
for isolates of different subgroups within an AG, and 55 – 96% for isolates of different AGs. In neighbor-joining trees based
on distances derived from ITS-5.8s rDNA sequences, subgroups IA, IB and IC within AG-1 and subgroups HG-I and HG-II within AG-4 were placed on statistically
significant branches as assessed by bootstrap analysis. These results suggest that sequence analysis of ITS rDNA regions of
R. solani may be a valuable tool for identifying AG subgroups of biological significance.
Received: 11 February /16 May 1997 相似文献
104.
F. Fernández-Cuenca L. Martínez-Martínez A. Pascual M. De Cueto O. Gutiérrez J. Nieto E. J. Perea 《Clinical microbiology and infection》2003,9(5):449-452
The aim of this study was to evaluate the WIDER I system for susceptibility testing of Haemophilus influenzae and Streptococcus pneumoniae . MICs of 12 antimicrobials against 42 H. influenzae and 58 S. pneumoniae strains were determined using 1W MIC panels and compared with those obtained by microdilution. Overall essential agreements were >99%. Very major errors were not detected. Major errors occurred with ampicillin (1.7% H. influenzae ). Minor errors were 2.3% (amoxicillin–clavulanate, cefuroxime, chloramphenicol), 7.1% (ampicillin) and 16.7% (clarithromycin) for H. influenzae , and 1.7% (chloramphenicol, erythromycin, meropenem), 3.4% (amoxicillin–clavulanate, cefuroxime, tetracycline) and 8.6% (levofloxacin) for S. pneumoniae . The WIDER I system is a reliable method for susceptibility testing of H. influenzae and S. pneumoniae . 相似文献
105.
Group behavioral treatment of retentive encopresis 总被引:1,自引:0,他引:1
L J Stark J Owens-Stively A Spirito A Lewis D Guevremont 《Journal of pediatric psychology》1990,15(5):659-671
Investigated the efficacy of behavioral group treatment for children with retentive encopresis who had previously failed medical management. Eighteen children between the ages of 4 and 11 years and their parents were seen in small treatment groups of 3 to 5 families over 6 sessions. The sessions focused on education about retentive encopresis, and the integration of behavioral parenting procedures with medical management. Parents and children were taught to deliver an enema clean-out, increase the children's dietary fiber, and appropriate toileting techniques. The results indicated that children significantly increased their fiber consumption by 40%, increased appropriate toileting by 116%, and decreased their soiling accidents by 83% pre- to posttreatment. Further, these treatment gains maintained or improved at the 6-month follow-up. The results are discussed in terms of cost-effective interventions and the interface between psychology and medicine in pediatric psychology. 相似文献
106.
A. Stathi J. Papaparaskevas L. Zachariadou A. Pangalis N. J. Legakis A. Tseleni-Kotsovili the Hellenic Strep-EURO Study Group P. T. Tassios 《Clinical microbiology and infection》2008,14(8):808-812
Among a total of 101 isolates from the first systematic multicentre surveillance effort concerning invasive Streptococcus pyogenes disease in Greece, conducted between 2003 and 2005 and covering 38% of the population, emm types 1 and 12 were prevalent, being responsible for 27 and nine cases, respectively. The isolates from the remaining 65 cases were assigned to 26 other emm types. Erythromycin resistance (12 isolates) was primarily mef (A)-mediated, although all emm type 1 strains were susceptible. Tetracycline resistance, due mostly to tet (M), was detected in 26 isolates. Subtyping by pulsed-field gel electrophoresis yielded 50 chromosomal fingerprints, thus discriminating further among ten of the 28 observed emm types. 相似文献
107.
108.
Stark Lori J.; Opipari Lisa C.; Donaldson Deidre L.; Danovsky Michael B.; Rasile Deborah A.; DelSanto Anne F. 《Journal of pediatric psychology》1997,22(5):619-633
Replicated the efficacy of a short-term, combined medical andbehavioral intervention protocol for retentive encopresis. Fifty-ninechildren who had failed standard medical management for retentiveencopresis and their parents participated in six 1-hour grouptreatment sessions. Treatment protocol combined the medicalmanagement strategies of enema clean out, increasing dietaryfiber, and daily toilet sitting with the child behavior managementstrategies of differential attention, contingency management,and contracting. For the overall sample, the number of soilingincidents decreased 85%, the weekly frequency of independentbowel movements increased 15%, the weekly frequency of parent-promptedbowel movements increased 9%, and daily dietary fiber intakeincreased 121% pre-to posttreatment. The majority of the sample(86%) stopped soiling by the end of treatment and did not requirefurther treatment. Results are discussed in terms of the comparabilitywith previous findings and the utility of combined medical andpsychological treatments for children with encopresis who havefailed standard medical approaches 相似文献
109.
Kontiokari T Renko M Kaijalainen T Kuisma L Leinonen M 《APMIS : acta pathologica, microbiologica, et immunologica Scandinavica》2000,108(11):734-738
It is not known how well nasopharyngeal swab culture represents pneumococcal carriage status. We tested this by comparing swab culture to quantitative culture and quantitative PCR of mucosal tissue in a rat model of pneumococcal carriage. Quantitative culture and quantitative PCR identified significantly more carriers compared to swab culture (differences 15% and 33%, 95% CI 1-28% and 16-47%, p=0.04 and 0.001, respectively). The sensitivity and specificity of swab culture was 75/92% and 63/100% compared to quantitative tissue culture and quantitative PCR, respectively. The quantitative estimates of culture and PCR were very similar (Pearson correlation coefficient 0.79, p<0.001). In conclusion, even a well-controlled swab sampling markedly underestimates pneumococcal carriage rate, and simultaneous use of quantitative culture and PCR increases the number of positive samples by about one third. 相似文献
110.
Sephadex—G50微柱凝胶血型试剂的研制和应用 总被引:1,自引:0,他引:1
目的 研制卡式微柱凝胶血型试剂并应用于血型血清学试验。方法 以Sephadex-G50超细凝胶为分子筛载体,制备成中性微柱凝胶试剂卡、特异性凝胶试剂卡及coomb’s凝胶试剂卡并用于血型鉴定、配血试验、抗体筛选和鉴定,对1000名献血者ABO及Rh(D)血型进行鉴定,其中A型272例、B型279例、B3亚型1例、0型437例、AB型11例;Rh(D)阴性2例,Rh(D)阳性998例;对100例输血前检查标本进行配血试验;以Coomb's凝胶试剂卡对抗-D、-C、-c、-E、-e、-Jk^a、-Jk^b、-Fy^a、-Di^a等9个抗体分别与谱红细胞反应做特异性抗体鉴定试验:同时以瑞士进口的DiaMed同类产品及常规的血型血清学试管法同步比较。结果 研制的卡式微柱凝胶血型试剂与瑞士进口的DiaMed同类产品比较,检验结果、敏感性、特异性无明显差别。结论 研制的卡式微柱凝胶试剂适用于血型鉴定、配血试验、抗体筛选和鉴定等血型血清学检查,该试剂制备具有成本低、工艺简单的优点,具有较好的推广应用和开发价值。 相似文献