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991.
Flow cytometry immunolabeling, tube agglutination tests, and thin-layer chromatography immunostaining with two different anti-A monoclonal antibodies (anti-A mAb1 and anti-A mAb2) and one anti-B mAb were used to demonstrate differences in expression of the A and B antigens among erythrocytes from type A and four different type AB cats. Although the flow cytometric patterns of reactivity and agglutination scores for erythrocytes from types A and B cats detected with the anti-A and anti-B mAbs were consistent, reactivity among erythrocytes of different type AB cats was variable. By flow cytometric analysis, 99.9% of type A erythrocytes, no type B erythrocytes, 2.5–4.0% of erythrocytes from type AB cats 1, 3, and 4, and 60.7% of erythrocytes from type AB cat 2 had detectable A antigen when anti-A mAb1 was used. In contrast, 86.4% of type A erythrocytes, no type B erythrocytes, 20.2–38.0% of erythrocytes from type AB cats 1, 3, and 4, and 68.5% of erythrocytes from type AB cat 2 had detectable A antigen when anti-A mAb2 was used. In addition, 86.9% of type B erythrocytes, no type A erythrocytes, 83.1–96.8% of erythrocytes from type AB cats 1, 3, and 4, and 73.0% of erythrocytes from type AB cat 2 had detectable B antigen when the anti-B mAb was used. Agglutination scores of type AB cats were comparable to the percent binding on flow cytometry. Thin-layer chromatography immunostains confirmed differences in the amount of A antigen between erythrocyte glycolipids of type A and AB cats and those of type AB cats 1 and 2. These results suggest that at least two different phenotypes exist within the feline AB blood type, which differ in the amount of A antigen expressed on the erythrocyte surface.  相似文献   
992.
Patients with Peutz-Jeghers syndrome (PJS) are known to be at risk of gastric cancer (GC), and the STK11 gene is a susceptibility gene for PJS. However, as no cases of PJS with GC in which a STK11 germline mutation has been identified have ever been reported and other susceptibility genes have also been suggested to be involved in PJS, the relation between STK11 germline mutations and GC in PJS is still unknown. In this study, we used sequencing analysis to investigate the STK11, CDH1, and TP53 loci for a germline mutation in two siblings with PJS with primary GC. A novel type of the STK11 germline mutation, c.890delG, encoding a truncated protein (p.Arg297fsX38) was identified, but no germline mutations of the CDH1 and TP53 genes were detected. No inactivation of the wild-type allele by somatic mutation or chromosomal deletion or hypermethylation at the 5'-CpG site of STK11 was detected in the GC. This is the first report of a STK11 germline mutation in a PJS patient with GC and should contribute to establishing correlations between the STK11 germline mutations and GC in PJS patients.  相似文献   
993.
Selnes A  Nystad W  Bolle R  Lund E 《Allergy》2005,60(7):894-899
BACKGROUND: During the last decades there has been extensive epidemiological research to explore the increasing prevalence of asthma and allergy in childhood. The worldwide variations in prevalence of these diseases necessitate regional rapports. Furthermore, time-trend analyses with comparable methods are important in order to monitor the rapidly changing prevalence of these diseases. METHODS: Three cross-sectional questionnaire-based studies of asthma and allergy in schoolchildren were conducted in the counties of Troms and Finnmark, in northern Norway in 1985, 1995 and 2000. The two former studies included children from randomly selected primary schools (n = 1794/1985, n = 1432/1995). The latter study was a part of ISAAC-II Europe study (n = 3853). Identical items of asthma and allergy were employed. The analyses comprised only children 9-11 years of age. RESULTS: The prevalence of asthma was 9.3, 13.2 and 13.8% in 1985, 1995 and 2000, respectively. However, great gender differences were detected; the prevalence of asthma increased in males from 1995 to 2000, from 14.1 to 17.0%, RR = 1.2 (95% CI 1.0-1.5), but decreased in females 1995 to 2000, from 12.3 to 10.5%, RR = 0.9 (95% CI 0.7-1.1). Furthermore, in children with asthma, a changing trend was found in the external factors that perceived symptoms, from typical allergens towards other, unspecific agents. The prevalence of self-reported atopic eczema/dermatitis syndrome (AEDS) was 13.4, 21.1 and 20.8% in 1985, 1995 and 2000, respectively. The prevalence of self-reported allergic rhinoconjunctivitis was in 16.5, 24.7 and 29.6% 1985, 1995 and 2000, respectively, RR (2000/1995) = 1.2 (95% CI 1.1-1.3). CONCLUSION: The prevalence of asthma in girls has reached a plateau and even decreased from 1995 to 2000 which is in contrast to the asthma prevalence in boys that tends to continuously increase. The prevalence of AEDS which increased substantially between 1985 and 1995 did not change from 1995 to 2000. However, the prevalence of allergic rhinoconjunctivitis increased steadily from 1985, 1995 to 2000.  相似文献   
994.
We sequenced the complete S segments of hantaviruses detected from 12 HPS patients living in southern of Brazil. Samples were obtained from patients diagnosed in different years, in distinct areas, and with a broad spectrum of clinical signs. Despite these differences, all the S proteins of hantavirus from Paraná were identical, except for one amino acid substitution. Phylogenetic analyses of the complete S segment nucleotide and amino acid sequences indicated that hantaviruses from Paraná form a distinct clade from those circulating in South and North America. Other hantaviruses from Brazil were not placed in the same clade. The Oligoryzomys nigripes-associated strains ITA37 and ITA38 from Paraguay were found to belong to the same clade as the hantaviruses from Paraná. Paraguay and Paraná state are located at the same latitude and some ecosystems are similar in both places. The geographic position and common rodent hosts could explain this phylogenetic relationship.  相似文献   
995.
OBJECTIVE: To examine whether patients with Tourette's syndrome (TS) with and without comorbid attention deficit and hyperactivity disorder (ADHD) differ in cognitive functioning and whether a higher level of cognitive functioning is associated with severity of TS symptoms and psychosocial functioning. METHODS: Cognitive functioning, symptom severity, and psychosocial functioning were examined in 40 patients (33 boys, 7 girls; age range 6-18 years) with TS, of whom 17 had the comorbid diagnosis of ADHD. RESULTS: Patients with a comorbid ADHD diagnosis evidenced poorer performance than those with TS alone with respect to severity of TS symptoms, psychosocial functioning, verbal and performance intelligence, and word fluency, but not on tests of cognitive flexibility. Psychosocial functioning was predicted by symptom severity, but not by intelligence or fluency. CONCLUSIONS: Results confirm prior findings that comorbid ADHD is associated with more TS symptoms and worse psychosocial and cognitive functioning, and motivate whether cognitive flexibility plays a role in moderating the deleterious psychosocial effects of Tourette's syndrome and ADHD.  相似文献   
996.
雷诺氏综合征患者的微循环特点和中西结合治疗   总被引:3,自引:0,他引:3  
对40例雷诺氏综合征(RDS)患者应用益气通阳活血化瘀中药与西药倍他乐克联合治疗,同时观察RDS患者治疗前后的甲襞微循环(NFM)、血液流变性和彩色多普勒血流显像(CDFI)变化。结果显示RDS患者经治疗后NFM明显改善,细动脉增宽、血流加快(P<0.05),全血粘度、血浆粘度、纤维蛋白原及体外血栓重量与长度明显减轻缩小(P<0.01);CDFI表现动脉痉挛消失,血流阻力下降以及血流量增加。提示:益气通阳活血化瘀中药和倍他乐克西药合用有明显的降粘、解聚、抗栓、改善微循环的作用,治疗RDS有较好的疗效。  相似文献   
997.
Klinefelter综合征患者和双亲对诱变剂敏感性研究   总被引:1,自引:1,他引:1  
为了解诱变剂对Klinefelter综合征发生的影响,对Klinefelter综合征患者,患者双亲及对照进行丝裂霉素C,乙醛或乙醇诱导非二倍体,染色体结构畸变及微核观察,发现丝裂霉素C诱导的患者当色体结构畸变和微核均显著多于对照和双亲,乙醛和乙醇能诱导非二倍体和微核增加,但患者和双亲增加的程度极显著高于对照,提示Klinefelter综合征患者对于丝裂霉素C,乙醛和乙醇诱导染色体畸变更敏感。双亲对  相似文献   
998.
Summary Genomic imprinting is a biological phenomenon determined by an evolutionally acquired, underlying system that may control harmonious development and growth in mammals. It is also relevant to some genetic disorders in man. In this article, lines of biological evidence of imprinting, characteristics of the mouse and human imprinted genes, and findings and mechanisms on the occurrence of several human imprinting disorders are reviewed.  相似文献   
999.
Three patients with Ehlers-Danlos syndrome type IV (EDS IV) and biochemical evidence of structural defects in collagen III were investigated for mutations within the collagen III gene ( COL3A1 ). Single strand conformation polymorphism analysis of α1(III) cDNA indicated the presence of different heterozygous sequence changes in each of the patients. Nucleotide sequencing revealed mutations leading to the substitution of glycine 400 with glutamic acid, glycine 595 with cysteine, and glycine 1003 with aspartic acid. EDS IV is a life-threatening disorder which, as the clinical histories of our patients and their families show, still often escapes diagnosis. Biochemical and molecular studies can clarify the diagnosis and help provide appropriate management and counselling.  相似文献   
1000.
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