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991.
等离子体表面改性涤纶材料的血浆蛋白吸附与血小板黏附行为研究 总被引:8,自引:0,他引:8
采用等离子体表面接枝改性技术在涤纶 (聚对苯二甲酸乙二醇酯 ,PET)材料表面接枝不同分子量的聚乙二醇 (PEG) ,从表面能与界面自由能的角度分析了血浆蛋白 (纤维蛋白原和白蛋白 )在材料表面的竞争吸附关系 ,结果表明接枝了 PEG长链分子的 PET材料具有优先吸附白蛋白的性质 ,其中接枝 PEG6 0 0 0的 PET优先吸附倾向最明显。预接触白蛋白和纤维蛋白原的 PET材料表面的血小板黏附实验表明 :吸附白蛋白的表面能够显著抑制血小板的黏附和聚集 ,表现出好的血液相容性 ,而吸附了纤维蛋白原的材料表面具有降低血液相容性的性质。 相似文献
992.
Loeys B De Backer J Van Acker P Wettinck K Pals G Nuytinck L Coucke P De Paepe A 《Human mutation》2004,24(2):140-146
In order to estimate the contribution of mutations at the fibrillin-1 locus (FBN1) to classical Marfan syndrome (MFS) and to study possible phenotypic differences between patients with an FBN1 mutation vs. without, a comprehensive molecular study of the FBN1 gene in a cohort of 93 MFS patients fulfilling the clinical diagnosis of MFS according to the Ghent nosology was performed. The initial mutation screening by CSGE/SSCP allowed identification of an FBN1-mutation in 73 patients. Next, sequencing of all FBN1-exons was performed in 11 mutation-negative patients, while in nine others, DHPLC was used. This allowed identification of seven and five additional mutations, respectively. Southern blot analysis revealed an abnormal hybridization pattern in one more patient. A total of 23 out of the 85 mutations identified here are reported for the first time. Phenotypic comparison of MFS patients with cysteine-involving mutations vs. premature termination mutations revealed significant differences in ocular and skeletal involvement. The phenotype of the eight patients without proven FBN1 mutation did not differ from the others with respect to the presence of major cardiac, ocular, and skeletal manifestations or positive familial history. Most likely, a portion of FBN1-mutations remains undetected because of technical limitations. In conclusion, the involvement of the FBN1-gene could be demonstrated in at least 91% of all MFS patients (85/93), which strongly suggests that this gene is the predominant, if not the sole, locus for MFS. 相似文献
993.
侯湘 《生物医学工程与临床》2005,9(3):153-154
目的鉴于MRI对组织的高分辨性能,利用该图像观察颈椎综合征患者的椎管外组织的病理状况.方法54例患者,其中男30例,女24例,分为2组.观察组44例颈椎综合征患者,对照组10例颈部外伤和三叉神经痛患者.通过常规的MRI矢状位及横轴位颈椎图像,比较两组软组织增生情况.结果与结论在颈椎综合征MRI的颈椎及上段胸椎棘突后侧,均可观察到不同程度的慢性纤维性变化,与对照组比较,有可比性.提示临床上颈椎综合征多与颈肩区筋膜炎、棘突炎相关,属于无菌性炎症,其慢性阶段,局部发生了纤维增生性改变.建议在观察分析此种病症的颈椎骨质及椎间盘改变的同时,宜重视棘突后侧的纤维性变化,有利于病理病因的研究. 相似文献
994.
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
995.
A novel STK11 germline mutation in two siblings with Peutz-Jeghers syndrome complicated by primary gastric cancer 总被引:1,自引:0,他引:1
Shinmura K Goto M Tao H Shimizu S Otsuki Y Kobayashi H Ushida S Suzuki K Tsuneyoshi T Sugimura H 《Clinical genetics》2005,67(1):81-86
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
996.
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
997.
Raboni SM Probst CM Bordignon J Zeferino A dos Santos CN 《Journal of medical virology》2005,76(4):553-562
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
998.
Brief report: cognitive functioning in children with Tourette's syndrome with and without comorbid ADHD 总被引:12,自引:0,他引:12
Brand N Geenen R Oudenhoven M Lindenborn B van der Ree A Cohen-Kettenis P Buitelaar JK 《Journal of pediatric psychology》2002,27(2):203-208
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
999.
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
1000.
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