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81.
目的 利用寡核苷酸芯片平行分析乙肝病毒表面抗原区S、前核心抗原pre C区、X区、聚合酶P区 12个已知的突变位点。方法 针对S、pre C、X、P区的 12个突变位点 ,设计位于乙肝病毒反义链的 2 4条寡核苷酸探针和两对PCR引物 ,探针长度为 14~ 18bp ,其 5′端连有氨基己烷和T15间隔子 ,合成后经点样仪点到醛基化玻片上。两对PCR引物分别用于扩增S与P区内的 5个突变位点和X、前C区内的 7个突变位点 ,其中上游引物含有荧光标记。不对称PCR扩增所得到的荧光标记的单链DNA与寡核苷酸阵列杂交、清洗后经扫描分析实验结果。结果 在对 12个乙肝阳性样品前核心抗原C和X区的突变检测中 ,存在 176 2A→T ,176 4G→A联合突变的有 2例、1896G→A突变的 3例、同时存在 176 2A→T、176 4G→A联合突变和 1896G→A突变的 1例、未存在任何突变的样品 6例。在 12个乙肝阳性样品的表面抗原S的突变检测中 ,未发现有突变出现。部分样品的随机测序结果与寡核苷酸阵列杂交结果一致。结论 寡核苷酸芯片适于快速、平行、大量检测突变 相似文献
82.
Dr. F. Eberle C. Aßmus G. A. Martini 《Journal of molecular medicine (Berlin, Germany)》1979,57(10):499-509
Zusammenfassung 3 Generationen mit 37 Mitgliedern einer Familie mit multipler endokriner Adenomatose Typ I (MEA Typ I) wurden anamnestisch und katamnestisch erfaßt. Klinische, biochemische und histologische Befunde wurden zusammengestellt: 20 Personen hatten Erkrankungen oder Befunde, die für eine MEA Typ I charakteristisch sind.Ein Patient (II 1) hatte ein chromophobes Hypophysenadenom, Epithelkörperchen- und Inselzelladenome, eine knotige Kolloidstruma und eine bilaterale knotige Nebennierenrindenhyperplasie. Dies ist das voll ausgeprägte Bild einer MEA Typ I (Wermer-Syndrom). Außerdem hatte er ein medulläres Schilddrüsencarcinom.Bei 14 Familienangehörigen ergaben sich Hinweise auf primären Hyperparathyreoidismus (pHPT), darunter waren 5 Patienten mit Nierensteinen. Die bei 3 Personen exstirpierten Epithelkörperchen erlaubten eine histologische Bestätigung der Diagnose pHPT. Die nach Möglichkeit mehrmals durchgeführte Bestimmung des Calcium- und Phosphatspiegels im Serum spielte eine Hauptrolle bei der Entdeckung von asymptomatischen Trägern des Gens.6 Patienten hatten Magen-Darmulcera: darunter waren 5 Patienten mit sicherem oder wahrscheinlichem pHPT, von denen aber nur einer (II 1) ein Gastrinom und eine Inselzelladenomatose hatte. Drei Patienten hatten eine Pankreatitis, bei zwei von ihnen nachweislich kombiniert mit pHPT. — Zweimal fand sich eine euthyreote Struma, einmal eine hyperthyreote Struma. Zwei Familienangehörige hatten erhöhte Plasmacortisolwerte; Lipome im Unterhautfettgewebe hatten ebenfalls zwei Patienten. Der Befund eines Alpha-1-Antitrypsinmangels (ZZ Phänotyp) bei zumindest 2 Patienten mit pHPT läßt an eine genetisch bedingte Verknüpfung des Defektallels Z mit der MEA Typ I denken. Weitere Familienuntersuchungen sind für eine Beweisführung notwendig.Ein Polyp im Jejunum mit heterotoper Magenschleimhaut (Fundus- und Pylorusdrüsen) ausgekleidet und blutend wurde bei diesem Syndrome noch nicht beschrieben. Der Befund wird von uns als Entwicklungsstörung des Entoderm aufgefaßt. Das bei einem Patienten (II 1) gefundene medulläre Schilddrüsencarcinom zeigt, daß die Trennlinie zwischen MEA Typ I und MEA Typ II nicht immer scharf gezogen ist. 相似文献
83.
Altintaş DU Karakoç GB Yilmaz M Pinar M Kendirli SG Cakan H 《Clinical & developmental immunology》2004,11(1):87-96
BACKGROUND: Aeroallergen sampling provides information regarding the onset, duration and severity of the pollen season that clinicians use to guide allergen selection for skin testing and treatment. OBJECTIVES: This atmospheric survey reports (1) airborne pollen contributions in Adana in one-year period (2) pollen onset, duration and peak level (3) the relationship between airborne pollen and selected meteorological variables and; (4) effects on symptoms in pollen allergic children. METHODS: Pollen sampling was performed with a volumetric Burkard Spore Trap. Meteorological data were measured daily from April 2001 to April 2002. Asthma symptom scores were investigated in 186 pollen allergic children that were on follow up in pediatric allergy outpatient clinics during same period. RESULTS: Average measurements included 82.5% tree pollen, 7.7% grass pollen and 9.8% herb pollen 54 taxa were identified during one year. The most prominent tree pollens were Cupressaceae, Eucalyptus and Pinus. The most common herb was Chenopodiaceae pollen family. When airborne pollen levels were examined in relation to single meteorological conditions; daily variations in total pollen counts were not significantly correlated with any variable studied (humidity, rainfall, temperature and wind) (p > 0.05). On the other hand, statistically significant relationship between pollen concentration and symptom scores were found (p > 0.05). Positive correlations were seen between both Gramineae and Herb pollen, and humidity and rainfall from March to July. However, positive correlations were detected between tree pollen counts and temperature and humidity in May and June. CONCLUSION: This survey is the first volumetric airborne pollen analysis conducted in the survey area in Adana. This study suggested that the effects of weather on pollen count and symptom scores in this population could not be clearly identified with the evaluation of one-year data. However, pollen counts had effect on allergic symptoms in pollen allergic children. Examination of the complex interaction of multiple whether parameters would perhaps more fully elucidate the relationship between meteorology and aerobiology and provide the clinician with information necessary to forecast pollen prevalence. An awareness of the ever chancing, local aeroallergen patterns requires regular monitoring. Such awareness serves as a useful guide in the effective testing and treatment of atopic patients. 相似文献
84.
Site-independent prognostic value of chromosome 9q loss in primary gastrointestinal stromal tumours 总被引:5,自引:0,他引:5
Gunawan B Schulten HJ von Heydebreck A Schmidt B Enders C Höer J Langer C Schüler P Schindler CG Kuhlgatz J Füzesi L 《The Journal of pathology》2004,202(4):421-429
Although the significance of tumour site for estimating malignant potential in gastrointestinal stromal tumours (GISTs) has recently been recognized, site-specific genetic patterns have not to date been defined. This study examined 52 c-kit-positive primary GISTs (with a mean follow-up of 42.3 months in 51 cases) from three different locations (35 gastric, 12 small intestinal, and five colorectal) using comparative genomic hybridization (CGH). In general, tumour site correlated with key prognostic factors, including tumour size, mitotic rate, proliferative activity, and probable malignant potential. Furthermore, several DNA copy number changes showed a site-dependent pattern. These included losses at 14q (gastric 83%, intestinal 35%; p = 0.001), losses at 22q (gastric 46%, intestinal 82%; p = 0.02), losses at 1p (gastric 23%, intestinal 88%; p = 1 x 10(-5)), losses at 15q (gastric 14%, intestinal 59%; p = 0.002), losses at 9q (gastric 14%, intestinal 53%; p = 0.006), and gains at 5p (gastric 11%, intestinal 53%; p = 0.002). These data demonstrate strong site-dependent genetic heterogeneity in GISTs that may form a basis for subclassification. Prognostic evaluation of DNA copy number changes identified losses at 9q as a site-independent prognostic marker associated with shorter disease-free survival (p = 0.03) and overall survival (p = 0.002). Furthermore, 9q loss also appeared to carry prognostic value in predicting overall survival for patients with advanced or progressive GISTs (p = 0.003). 相似文献
85.
目的 研究两种不同的IL-15真核表达质粒对乙肝蛋白疫苗诱导的免疫应答的影响。方法:构建IL-15真核表达质粒(简称pIL-15)和含有IL-12信号肽的IL-15真核表达质粒(简称pIL-2s-15),CTLL-2细胞增殖实验验证两种质粒真核表达产物的生物学活性。将这两种质粒分别与HBsAg共免疫BALB/C小鼠,用ELISA法检测小鼠血清抗-HBs IgG及IgGl、IgG2a亚类的效价。结果:与HBsAg蛋白疫苗共免疫时,pIL-15可使HBsAg诱导的抗-HBsIgG效价升高,显著高于载体pcDNA3.1与HB—sAg共免疫对照组,pIL-2s-15对HBsAg诱导抗-HBsIgC效价没有明显影响。与HBsAg pcDNA3.1组相比,HBsAg pIL-2s-15组和HBsAg pIL-15组诱生的抗HBsIgG2a亚类均升高,但前者IgG2a/IgG1比值最高,与HBsAg pcDNA3.1组相比差别有显著性;HBsAg pIL-15组IgG2a/IgG1比值与HBsAg pcDNA3.1组相比差别无显著性。结论 pIL-15真核表达质粒可增强蛋白疫苗诱导的体液免疫应答,pIL-2s-15真核表达质粒则主要使免疫应答趋向Th1型。 相似文献
86.
Biological and clinical significance of cytogenetic abnormalities in low-risk and high-risk gastrointestinal stromal tumors 总被引:3,自引:0,他引:3
Gunawan B Bergmann F Höer J Langer C Schumpelick V Becker H Füzesi L 《Human pathology》2002,33(3):316-321
We report cytogenetic findings in 19 c-Kit-positive gastrointestinal stromal tumors (GISTs) that represent a heterogenous group of mesenchymal neoplasms with respect to site, histology, and biologic behavior. All of the GISTs (5 low-risk, 11 high-risk, 3 recurrences) displayed clonal chromosomal aberrations; 15 were hypo- to near-diploid, and 4 were near-triploid and hypotetraploid. The most common abnormalities were loss of chromosomes 14 and/or 22, demonstrated in 14 GISTs irrespective of site or predominant phenotype. Ten cases (2 low-risk, 5 high-risk, 3 recurrences) were characterized by loss of both chromosomes 14 and 22, 2 cases (1 low-risk, 1 high- risk), by loss of chromosome 14; and 2 high-risk cases, by loss of chromosome 22. Additional chromosomal aberrations occurred preferentially in high-risk and recurrent GISTs, including loss of 9p and 1p in 8 cases each, loss of 15 in 6 cases, loss of 3p in 5 cases, loss of 13q and 10q in 4 cases each, loss of 19 in 3 cases, and complete or partial gains of chromosomes 5 and 4 in 2 cases each. More significantly, 5 of 6 patients with clinically aggressive GISTs, including 2 recurrences and 3 metastasing GISTs, were additionally characterized by loss of 9p; four of these had additional loss of chromosomes 1p and 15. The presented results herein indicate that loss of chromosome 14 and/or 22 is an early change in GIST tumorigenesis irrespective of site or differentiation, whereas malignant transformation and progression of GISTs appear to be associated with an increasing incidence of additional secondary aberrations. 相似文献
87.
抗人大肠癌单链抗体的构建、表达及其体内外生物学活性的检测 总被引:1,自引:2,他引:1
目的 将抗人大肠癌单克隆抗体ND-1(mAb)的VR和VL基因进行重组,构建和表达ND-1scFv,并对其在体内外的生物学活性进行检测。采用RT-PCR技术,从能够分泌mAb ND-1的鼠杂交瘤细胞中扩增VH和RL基因,通过重叠延伸拼接PCR在VH和VL基因间引入连接短肽,体外构构建ND-1scFv基因,并在大肠杆菌中表达。采用间接免疫荧光(IFA)EY IF工IMPG-1scFv的免疫学活性。用^99Tc^m标记ND-1scFv后,将偶联物给予荷瘤裸鼠,观察其在动物体内的显像及生物学分布。结果 SDS-PAGEW显示,重组蛋白Mr为30000,同预期结果一致。IFA及ELISA检测表明,ND-1scFv保留了与亲本抗体相近的免疫学活性,对表达相应抗原的靶细胞具有行异结合活性。体内放射免疫实验显示,^99Tc^m-ND-1scFv在荷瘤小鼠体内的生物学分布,呈明显的肿瘤积聚趋向,注入体内1h血中T/NT即在2.61。结论 获得免疫学活性良好的ND-1scFv,对荷瘤动物体内肿瘤的定位快速,准确,可望成为有效的肿瘤诊断和治疗的导向载体。 相似文献
88.
Mansour Mohamadzadeh Anastassia Pavlidou Alexander Enk Jürgen Knop Erwin Rüde Gernot Gradehandt 《European journal of immunology》1994,24(12):3170-3174
The antibody 4F7 was reported to recognize an epitope expressed on dendritic cells (DC) from various tissues. To study the ability of splenic 4F7+ dendritic cells to process antigen for presentation to CD4+ T cells, DC were enriched using a separation procedure avoiding overnight culture which could lead to an altered phenotype. These DC were used as antigen-presenting cells (APC) in stimulation cultures of major histocompatibility complex class II-restricted T cells. It was found that they induce antigen-dependent lymphokine production by T cells and therefore could present exogenous antigens. These processing takes place intracellularly, because fixation abrogates presentation to T cells. Moreover, antigen presentation needs intracellular processing within endo- or lysosomes as chloroquine-treatment prevents T cell activation. Titration of APC numbers revealed that contaminating APC most likely did not account for antigen-specific T cell activation by DC. No evidence was found for release of antigenic peptides or for partial antigen processing possibly done by cell surface located enzymes on DC. In conclusion, these results indicate that freshly enriched DC are able to process antigens similarly to other APC. 相似文献
89.
体外厌氧条件下载铜蒙脱石杀菌效果的研究 总被引:9,自引:0,他引:9
载铜蒙脱石的杀菌作用通过脑心浸液肉汤 (BHI)二倍系列稀释法来判定其最小抑菌浓度 (MIC)。释放入肉汤和生理盐水中Cu2 的量通过原子吸收光谱仪测定。杀菌动力学研究采用改良的振荡瓶法。结果表明 :厌氧条件下 ,载铜蒙脱石具有很强的杀菌性能。载铜蒙脱石对放线共生放线杆菌的最小抑菌浓度为 2 .5 6mg/ml;对血液链球菌为 5 .12mg/ml。测得肉汤二倍稀释的载铜蒙脱石释放出的Cu2 量在 2 .39~ 38.6 5 ppm之间 ,在生理盐水中释放的Cu2 量为 1.85~ 15 .82ppm。本试验结果表明 ,蒙脱石无抗菌性能。 相似文献
90.
SARS疫情期间公众心态影响及变化趋势分析 总被引:9,自引:0,他引:9
目的:探索重大突发性公共卫生事件对社会公众心理行为的影响,以及在不同阶段中公众心态变化的特点。方法:对SAILS流行期间374人次的心理咨询记录进行分析,依据疫情发展情况,比较各阶段的差异。结果:在咨询者中,女性(59.4%)多于男性(40.6%);根据疫情变化将咨询记录数据划分为三个阶段,分析发现随着疫情缓和,针对SARS症状的咨询者显著减少,从13.1%降低到1.8%;有关社会生活的咨询者显著增多,从8.7%上升到12.3%;在有关情绪问题的咨询者中,伴有相关症状者显著减少,从23.0%降低到4.5%;不伴相关症状者显著增多,从77.0%上升到95.5%。结论:整个SAILS疫情期问,情绪问题始终占第一位;随SARS疫情缓和,社会公众对于疾病本身的关注减少,而与疫情有关的社会生活问题增多;面对突发性公共卫生事件,及时开通心理咨询热线电话是十分必要的。 相似文献