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1.
胰腺肿瘤的B型超声诊断 总被引:4,自引:0,他引:4
本文将资料完整的并经手术及病理证实的27例胰腺肿瘤初步小结。详细描述各例肿瘤的临床们诊与诊断、B型超声和手术情况,并重点讨论:临床们诊和B型超声未能检出的肿瘤,检出肿瘤大小较手术所见尺寸的要,10mm~40mm以及未见肿瘤浸润的原因。 相似文献
2.
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
3.
Incidence and case-fatality rates resulting from the 1998 enterovirus 71 outbreak in Taiwan 总被引:6,自引:0,他引:6
Lu CY Lee CY Kao CL Shao WY Lee PI Twu SJ Yeh CC Lin SC Shih WY Wu SI Huang LM 《Journal of medical virology》2002,67(2):217-223
In 1998, an epidemic of hand-foot-and-mouth disease and herpangina caused by enterovirus 71 occurred in Taiwan, leaving many fatalities and severely handicapped survivors in its wake. The reasons this rather common pathogen would cause such a large-scale epidemic remain unknown. A seroepidemiological survey to elucidate the epidemiological characteristics of this outbreak, including its incidence and case-fatality rates was undertaken. Microneutralization tests for antibodies against enterovirus 71 were used to screen four collections of serum samples: 1) 202 specimens taken from individuals > or = 4 years old in 1994; 2) 245 specimens collected from individuals of all ages in 1997; 3) 1,258 specimens collected from individuals of all ages in 1999; and 4) sera samples from a birth cohort of 81 children who had yearly blood samples taken from 1988-98. After the maternal antibody had declined, the seropositive rates began to increase with age. Approximately half of all children aged 6 years or older were enterovirus 71 seropositive. Significantly higher seropositive rates were noted in 1999 than in 1997, in children aged 0.5-3 years. The incidence of enterovirus 71 infection during the epidemic was estimated to be 13-22%, with the higher rates in younger children. The case-fatality rate was highest (96.96 per 100,000) in infants aged 6-11 months, and declined in older children. The results showed that enterovirus 71 is endemic in Taiwan. The apparent lack of large-scale enterovirus 71 activity in the 3 years before 1998 might have been the prelude to the epidemic's appearance in 1998, and might suggest that enterovirus 71 infection will reappear every few years. The lack of a protective antibody in younger children may account for the high incidence and case-fatality rate in this age group. 相似文献
4.
BACKGROUND: The skin of patients with atopic dermatitis (AD) exhibits a striking susceptibility to colonization and infection by Staphylococcus aureus. The exotoxins secreted by S. aureus can act as superantigens and classic allergens, inducing the production of functionally relevant specific IgE antibodies. The aim of this study was to compare the levels and positive rates of serum staphylococcal enterotoxin A (SEA)- and staphylococcal enterotoxin B (SEB)-specific IgE between atopic children with and without AD. METHODS: Sixty children with AD, 55 children with respiratory allergy without AD, and 24 nonatopic healthy children were studied. The levels and positive rates of serum SEA- and SEB-specific IgE were compared among three groups. The correlation between the levels or positive rates of serum SEA/SEB-specific IgE and the severity of AD or the presence of previous skin infections was studied. RESULTS: The children with AD had significantly higher levels and positive rates of serum SEA- and SEB-specific IgE than the atopic children without AD (P < 0.001) and the nonatopic children (P < 0.001). There was no significant difference in the levels and positive rates of serum SEA- and SEB-specific IgE between the atopic children without AD and the nonatopic children. With or without adjustment for the potential confounding effect of total serum IgE levels, the levels and positive rates of serum SEA- and SEB-specific IgE were significantly correlated with severity of AD (P <0.005), but they were not significantly different between AD children with and without previous skin infections. CONCLUSIONS: SEA and SEB may contribute to chronic inflammation and exacerbation of AD through the IgE-mediated immune response. 相似文献
5.
西京医院冠心病介入治疗537例 总被引:1,自引:1,他引:0
目的 总结西京医院冠心病介入治疗的成功率及并发症发生率 .方法 回顾性分析 1998- 12前所有冠心病介入治疗病历完整患者的临床资料 .结果 在 5 37例患者中 ,6 9.3%为不稳定性心绞痛 ,2 0 .3%射血分数≤ 40 .0 % ,6 4.6 %为多支病变 .治疗血管 6 71支、病变 76 9处 ,B,C型病变77.9% .介入治疗病例成功率为 89.2 % .病变成功率 89.1% ,严重并发症发生率为 3.4% (死亡 1.9% ,Q波心梗 2 .0 % ,急症冠脉搭桥术 0 .2 % ) .普遍应用支架前后对比 ,病例成功率提高 (91.0 % vs80 .0 % ,P<0 .0 1) ,严重并发症发生率下降 (2 .6 % vs 6 .4% ,P<0 .0 5 ) .结论 我院病例病情严重 ,介入治疗成功率和并发症发生率与国外文献报道相似 .支架提高了介入治疗的安全性 相似文献
6.
碳源及添加模式对钝齿棒杆菌JDN28-75发酵生产L-精氨酸的影响 总被引:5,自引:0,他引:5
研究了不同碳源及添加模式对钝齿棒杆菌JDN28-75发酵生产L-精氨酸的影响,结果显示葡萄糖为合适的碳源.初始葡萄糖浓度为10%时,在发酵至24h左右补加葡萄糖有利于精氨酸的积累.5L全自动发酵罐中,初始葡萄糖浓度10%,发酵20h后以2.5g/h连续流加葡萄糖至总糖浓度为15%,与初糖浓度15%的批次发酵相比,L-精氨酸含量从2.98%升至3.72%,糖酸转化率由23.8%增至26.4%. 相似文献
7.
8.
9.
吡格列酮对内皮祖细胞增殖、凋亡及功能的影响 总被引:1,自引:0,他引:1
目的:观察不同浓度吡格列酮对大鼠骨髓源性内皮祖细胞(EPCs)增殖、凋亡和功能的影响,并探讨其可能的作用机制.方法:正常SD大鼠24只,随机分为A组(对照组)和B,C,D组[吡格列酮组剂量依次为10,20,40 mg/(kg·d)],灌胃处理10 d后断颈处死,密度梯度离心法获取骨髓单个核细胞,经鉴定后证实为EPCs. 每组细胞培养4 d后消化、计数并用完全培养液培养. 24 h后检测NO生成量,3 d后检测凋亡情况,7 d后检测增殖能力. 结果:与A组相比,B,C,D组EPCs增殖能力明显增高[B,C,D组A490 nm分别为(0.423±0.004), (0.680±0.008), (0.443±0.005) vs A组A490 nm (0.143±0.006), P<0.01];凋亡程度降低[B,C,D组分别为(32.8±0.8)%, (30.9±2.3)%,(33.0±3.9)% vs A组(40.1±1.1)%, P<0.01];培养上清中NO浓度显著提高[B,C,D组分别为(29.2±3.7), (41.0±7.7), (28.7±6.4) μmol/L vs A组(18.9±1.4), P<0.05];与C组相比,B组和D组促进EPCs增殖能力弱(P<0.01),培养上清中NO浓度相对低(P<0.05). 结论:不同浓度吡格列酮均能提高EPCs数量和功能;20 mg/(kg·d)吡格列酮对EPCs的作用较强. 相似文献
10.
Currently used methods of examining the mechanical properties of blood vessel walls are either indirect or invasive, or measure vessel diameter and pressure waveforms at different sites. We developed a noninvasive technique to assess the mechanical properties and viscoelasticity of peripheral arteries. The pressure-strain elastic modulus (Ep) and the viscoelastic properties (energy dissipation ratio, EDR) of the common carotid artery (CCA), brachial artery (BA), radial artery (RA) and dorsalis pedis artery (DPA) were determined by means of palpating pressure and diameter distension waveforms extracted from high-resolution ultrasonography. The methodology was validated in vitro using an elastic tube phantom, as well as in vivo. In vivo study in 10 healthy volunteers (mean age 22 y) showed that the pressure-diameter curves were nonlinear, with an inflection at about 85–90 mmHg, and routed clockwise with slight hysteresis. The CCA (n = 5) had a mean diameter of 6.74 mm and the pulsatile diameter distension was 12.2%. The Ep calculated at the CCA was 0.44 × 106 dyne/cm2 with an EDR of 7.18%. The BA, RA and DPA (n = 10) had mean diameters of 3.91 mm, 2.21 mm and 2.12 mm; arterial strains of 4.60%, 4.25% and 8.91%; mean Ep of 1.39, 1.45, 0.90 × 106 dyne/cm2; and mean EDRs of 6.34%, 6.15% and 5.60%, respectively. The method presented is relatively simple to implement clinically and has potential as a new diagnostic tool for detecting local vascular changes. 相似文献