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51.
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   
52.
53.
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   
54.
目的探讨醛固酮合成酶(CYB11B2)基因多态性与怀化侗族高血压高发人群原发性高血压(EH)及血脂水平的关系.方法采用聚合酶链反应结合限制性内切酶片段长度多态分析方法(PCR-RFLP)检测89例怀化侗族高血压病人和85例正常人的CYB11B2-344C/T等位基因频率和基因型频率.结果高血压组CYB11B2-344C/T基因型频率(CC 10.1%、CT41.6%、TT 48.3%)和等位基因频率(C 30.9%、T 69.1%)与正常对照组基因型频率(CC 10.3%、CT 27.6%、TT 62.1%)和等位基因频率(C 24.1%、T 75.9%)比较无显著性差异.CC基因型患者与CT TT基因型患者比较,收缩压和舒张压无显著性差异.结论怀化侗族人群EH可能与CYB11B2基因多态性无关.  相似文献   
55.
OBJECTIVE: To evaluate an integrated group intervention for siblings and parents designed to increase sibling understanding of and adjustment to chronic illness and developmental disability (CI/DD). METHODS: Fifty-four well siblings (ages 8-13 years) and their parents were recruited through hospital-based and community agencies serving children with CI/DD. Measures of sibling knowledge, sibling adjustment to the disorder, sibling connectedness, and sibling global behavioral functioning were collected before and after the intervention. A subsample of 20 families completed a 3-month follow-up to assess maintenance of results. RESULTS: Sibling knowledge of the child's disorder and sibling connectedness increased, while sibling reports of negative adjustment to the disorder and parent reports of sibling global behavioral functioning decreased significantly from pre- to posttreatment for both boys and girls, regardless of the type of diagnostic condition. Improvements in sibling knowledge, connectedness, and behavioral problems maintained at 3-month follow-up. Parent satisfaction with the program was high. CONCLUSIONS: Results support the future conduct of more controlled evaluation of the integrated sibling and parent group intervention model to improve sibling knowledge of and adjustment to CI/DD.  相似文献   
56.
ABO血型基因分型及应用   总被引:11,自引:0,他引:11  
目的 :研究ABO血型基因分型的意义。方法 :采用聚合酶链反应 序列特异性引物 (PCR SSP)基因定型方法对ABO血型基因定型并观察其基因多态性分布特征和疑难血型检定。结果 :对已知ABO基因的DNA标本进行基因定型 ,证实文中的ABO基因定型方法可靠 ;对 10 4例健康、无血源关系的汉族个体ABO血型基因定型 ,结果与血清学所定表型完全符合 ;并用ABO基因分型技术解决临床输血前血型鉴定、产前胎儿血型鉴定、亲权试验及血清学亚型的正确性验证。结论 :ABO血型基因分型技术可以正确判定ABO血型疑难样本  相似文献   
57.
Summary The 5,969 by (base pair) DNA sequence of the apocytochrome b mitochondrial (mt) gene of race A Podospora anserina was located in a 8.5 Kbp region. This gene contained a 2,499 by subgroup IB and a 1,306 by subgroup ID intron as well as a 990 bp subgroup IB intron which is present in race A but not race s. The large subgroup IB intron and the race A specific IB intron both contained potential alternate splice sites which brought their open reading frames into phase with their upstream exon sequences. All three introns were compared with regard to their secondary structures and open reading frames to the other 30 group I introns in Podospora anserina, as well as to other fungal introns. We detected a new family of intronic ORFs comprising seven P. anserina introns, several N. crassa introns, as well as the T4td bacteriophage intron. Sequence similarities to intron-encoded endonucleases were noteworthy. The DNA sequences reported here and in the accompanying paper complete the analysis of race s and race A mitochondrial DNA.  相似文献   
58.
Forty-six medullary thyroid carcinomas (MTC) were subjected to a qualitative and quantitative characterization of native and sialic acid masked Lewisa (Lea) antigens. Immunohistochemical investigations included monoclonal antibodies (MABs) directed against alpha(2,3)-sialyl-Lea, i.e. CA19-9 (MAB 19-9), native Lea (MAB anti Lea) and alpha(2,3) sialyl type 1 structure, i.e. CA 50 (MAB C50). To detect sialic acid masked Lea reactivity, MAB anti-Lea was also applied to native and enzymatically desialylated tissue sections with and without masking of sialic acid residues by sialic acid and sequence specific lectins. Only 7 MTC (15%) displayed a weak expression of CA19-9, while 16 (33%) showed moderate positive staining for native Lea. Twenty-seven tumours exhibited a strong staining by the N'ase MAB anti Lea staining sequence. The latter could most effectively be inhibited by the simultaneous masking of alpha(2,3)-and alpha-(2,6)-linked sialic acid residues due to the comptetitive binding of sialic acid and sequence specific lectins: Maackia amurensis agglutinin (specific alpha(2,3)-linked sialic acid) and Sambucus nigra agglutinin (specific alpha(2,6)-linked sialic acid). Thus, in MTC the major portion of sialic acid masked Lea antigen reactivity is different from that detected by the MAB 19-9. The antigen reactivity is probably due to Lea structures containing both alpha(2,3) and alpha(2,6)-linked sialic acid residues. A highly significant correlation between the expression of CA50 and that detected by the N'ase MAB anti-Lea staining sequence indicates that the alpha(2,3)-sialyl type 1 chain represents a common intermediate structure within the pathway of the biosynthesis of sialylated Lea antigens, excluding the formation of CA19-9 via the formation of the disialyl type 1 structure. This is subsequently fucosylated to the corresponding sialic acid masked Lea. Preliminary clinicopathological studies indicate that the sialic acid masked Lea antigens detected by the N'ase MAB anti-Lea staining sequence are related to biologically aggressive MTC.  相似文献   
59.
Summary Hypotensive brain stem necrosis is reported in a stillborn. Additional postmortem findings included evidence of intrauterine distress, shock, and a pure blood culture of group B -hemolytic streptococci. These findings suggest group B -hemolytic streptococcal sepsis in utero, with a subsequent episode of transitory circulatory failure prior to intrauterine demise.  相似文献   
60.
目的 研究1例ABO亚型及基因特征。 方法 采用试管法对家系3代共7例标本进行ABO血型血清学鉴定;对正反定型不一致的标本运用聚合酶链式反应序列特异性引物(polymerase chain reaction-sequence specific primer, PCR-SSP)法基因分型;并对ABO基因第6和7外显子扩增产物进行测序分析。 结果 ABO血型血清学发现7例标本中正反定型不符3例,其中2例红细胞表型为cisAB/A 或ABx,1例为cisAB/O或A2Bx;基因分型为ABO*cisAB01/A101、ABO*cisAB01/O01。ABO基因序列分析:ABO*cisAB01/A101第7外显子发生467C>T、803G>C的特征性突变,ABO*cisAB01/O01第6外显子261位缺失G,第7外显子在467C>T、803G>C存在特征性突变。测序结果均携带有ABO*cisAB01基因。 结论 ABO*cisAB01基因能导致A抗原或者B抗原的弱表达并能稳定遗传,因此应将血型血清学和分子生物学方法相结合才能准确鉴定ABO亚型。  相似文献   
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