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991.
人源性抗-HBc单链噬菌体抗体库的构建 总被引:4,自引:0,他引:4
目的 构建人源性单链噬菌体抗体库,为筛选人源性抗—HBc单链抗体奠定基础。方法 利用逆转录—聚合酶链反应(RT—PCR)和噬菌体表面展示技术,直接从乙肝病毒核心抗体(抗—HBc)阳性患者淋巴细胞中提取总RNA,逆转录成cDNA;合成全套人抗体可变区引物扩增抗体可变区基因,并将重、轻链可变区基因进行拼接装配成单链抗体(ScFv)基因,重组于噬菌粒载体叶pHEN1,转化抑制型大肠埃希菌E.coliTG1,以辅助噬菌体援救后,构建成人源性单链噬菌体库。结果 成功地构建了人源性抗—HBc单链噬菌体库,库容量达10^6。结论 利用RT—PCR和噬菌体表面展示技术可以成功构建人源性单链抗体库,并达到建库标准,可进一步从中筛选人源性单链抗体。 相似文献
992.
多孔髓芯减压联合髋关节镜清理术治疗早期股骨头缺血坏死 总被引:1,自引:0,他引:1
目的 观察多孔髓芯减压联合髋关节镜清理术治疗早期股骨头缺血坏死(ANFH)的疗效.方法 将60例早期ANFH患者随机分为观察组23例(30髋)和对照组25例(30髋),分别行多孔髓芯减压联合髋关节镜清理术及传统股骨头髓芯减压术,术后采用髋关节Harris评分及影像学检查评定治疗效果.结果 患者均获随访5个月~3 a(平均32.3个月),术中、术后无严重并发症发生;观察组和对照组临床成功率分别为86.7%、60.0%(P<0.05),影像学成功率为83.3%、70.0%(P<0.05).结论 多孔髓芯减压联合髋关节镜清理术治疗早期ANFH短期疗效肯定,长期疗效有待于进一步观察. 相似文献
993.
[目的]观察肝郁气滞型、脾胃虚弱型、肝郁脾虚型肠易激综合征(IBS)患者脑肠肽的变化,探讨IBS的中医虚实证型与血浆脑肠肽水平变化的相关性。[方法]90例IBS患者分为肝气郁滞证组、肝郁脾虚证组、脾胃虚弱证组各30例,正常对照(正常)组10例,应用放射免疫法同批测定血浆血管活性肠肽(VIP)、神经肽Y(NPY)和神经降压素(NT)水平。[结果]3个证型组患者血浆VIP水平显著高于正常组(P〈0.05,〈0.01);脾胃虚弱、肝郁脾虚证组患者VIP水平显著高于肝气郁滞证组(P〈0.05),但脾胃虚弱证组和肝郁脾虚证组之间比较差异无统计学意义。3个证型组患者血浆NPY水平显著低于正常组(P〈0.05,〈0.01),肝郁脾虚证组和肝气郁滞证组NPY水平明显低于脾胃虚弱证组(P〈0.01,〈0.05),肝郁脾虚证组NPY水平低于肝气郁滞证组,但2组比较差异无统计学意义。3个证型组患者血浆NT水平显著高于正常组(P〈0.01)。3证型间比较差异无统计学意义。[结论]不同中医证型IBS脑肠肽存在不同的变化。IBS的中医病机观与现代医学所倡导的脑-肠轴学说具有相关性。 相似文献
994.
Chu CJ Keeffe EB Han SH Perrillo RP Min AD Soldevila-Pico C Carey W Brown RS Luketic VA Terrault N Lok AS 《Gastroenterology》2003,125(2):444-451
BACKGROUND & AIMS: Hepatitis B virus (HBV) genotypes may be related to severity of liver disease and treatment response. The aims of this nationwide study were to determine the prevalence of HBV genotypes in the United States and the association between HBV genotypes and patient demographics, mode of infection, and clinical status. METHODS: A total of 694 consecutive chronic HBV-infected patients seen in 17 U.S. liver centers during a 1-year period were enrolled. Demographic, clinical, and laboratory data were collected. Sera were tested for HBV genotyping, precore, and core promoter variants by line-probe assays. RESULTS: All 7 HBV genotypes (A-G) were found, with genotypes A and C the most common. The prevalence of HBV genotypes was different in different regions of the United States. A strong correlation was found between HBV genotypes and ethnicity. HBV genotype A was prevalent among white and black patients, whereas genotypes B and C were most common among Asian patients. The predominant genotype among patients born in the United States, Europe, the Far East, and Southeast Asia were A, D, C, and B, respectively. Genotypes A and C were associated with a higher prevalence of hepatitis B e antigen. Precore variant was detected in 27% of patients and core promoter variant in 44% of patients. CONCLUSIONS: Our study suggests that the epidemiology of HBV infection in the United States may have changed over time as a result of immigration from countries with a high prevalence of HBV infection. HBV genotypes may account for the heterogeneity in disease manifestations among patients with chronic HBV infection. 相似文献
995.
Pascual Figal DA Cerdán Sánchez MC Noguera Velasco JA Casas Pina T Muñoz Gimeno L García Rodríguez R Ruipérez Abizanda JA Martínez Hernández P Valdés Chávarri M 《Revista espa?ola de cardiología》2005,58(10):1155-1161
INTRODUCTION AND OBJECTIVES: Measurement of N-terminal pro-B-type natriuretic peptide (NTproBNP) helps in diagnosing heart failure (HF). The test's usefulness may be greatest in patients with severe dyspnea of uncertain origin. However, NTproBNP has not been evaluated specifically in this setting. PATIENTS AND METHOD: This prospective emergency department study included 70 patients with shortness of breath at rest as their chief complaint. In the attending physician's opinion, both HF and a non-cardiac cause were equally probable. Blinded NTproBNP measurement was carried out in blood samples collected on admission. Patients were monitored and their final diagnoses were based on clinical findings, therapeutic responses, and cardiac and noncardiac tests performed during hospitalization. RESULTS: The NTproBNP level was higher in the 49 patients (70%) with a final diagnosis of HF (P = .006); the area under the ROC curve was 0.72 (0.60-0.82). The optimum diagnostic cut-off value was 900 pg/mL, which had an accuracy of 87%, a sensitivity of 98%, and a negative predictive value of 92%. The NTproBNP level was significantly higher in the 6 patients (9%) who died during hospitalization (P = .009); the area under the ROC curve was 0.87 (0.76-0.93) and the optimum cut-off value for predicting death was 5500 pg/mL, which had an accuracy of 77%, a sensitivity of 100%, and a positive likelihood ratio of 4.2. CONCLUSIONS: In patients with severe dyspnea and an uncertain diagnosis of HF, an NTproBNP level < 900 pg/mL helps exclude the presence of HF, whereas a NTproBNP level > 5500 pg/mL identifies patients at an increased risk of death. 相似文献
996.
"免疫耐受期"慢性乙型肝炎病毒感染者临床与肝脏病理学特点 总被引:1,自引:0,他引:1
目的 了解免疫耐受期慢性HBV感染者临床及肝脏病理学特征.方法 分析98例"免疫耐受期"慢性HBV患者年龄、性别、血清HBV DAN水平、肝脏炎症活动度及纤维化程度、肝脏HBsAg和HBcAg表达情况.并对不同血清ALT水平的肝脏炎症活动度及纤维化程度进行比较.采用X2检验.结果 98例患者中,<30岁者83例,占84.7%,≥30岁者15例,占15.3%.有48.0%感染者的母亲HBsAg阳性.所有感染者血清HBVDNA为高水平复制,>1×107拷贝/mL者占78.5%.仅5例感染者肝脏炎症活动度为Go,占5.1%;其中G1 64例,占65.3%;G2 29例,占29.6%.56例肝脏无明显纤维化(SO),占57.1%;S1 23例,占23.5%;S2 14例,占14.3%;S3 5例,占5.1%;未发现肝硬化.肝组织HBsAg阳性79例,占80.6%;HBeAg阳性80例,占81.6%.血清ALT在正常范围高水平的感染者肝脏纤维化程度明显高于ALT低水平者(X2=8.112 3,P=0.043 7).结论绝大部分"免疫耐受期"慢性HBV感染者肝脏存在轻度炎性反应,部分已出现纤维化;对"免疫耐受期"HBV感染者进行肝脏病理学检查,有利于正确判断病情和确定治疗方案. 相似文献
997.
Background: Mortality from colon cancer is significant with an expected 30,350 colon cancer deaths in 2005 with current treatment(s).
Long-acting natriuretic peptide, vessel dilator, kaliuretic peptide, and atrial natriuretic peptide have significant anticancer
effects in breast and pancreatic adenocarcinomas.
Aim of Study: Whether these peptide hormones have anticancer effects in colon adenocarcinoma cells and whether these effects are specifically
mediated by cyclic GMP has not been determined.
Methods: These peptide hormones were evaluated for anticancer effects in human colon adenocarcinoma cells and to determine whether
their anticancer effects are specifically mediated by cyclic GMP.
Results: There was a 89–97% decrease (p<0.001 for each) in colon adenocarcinoma cells within 24 h with 1 mM of these peptide hormones. There was a significant (p<0.05) decrease in human colon cancer cell number with each 10-fold increase in concentration from 1 to 1000 μM (i.e., 1 mM) of these four peptide hormones without any proliferation in the 3 d following this decrease. These same hormones decreased
DNA synthesis 65–83% (p<0.001). Cyclic GMP antibody inhibited 75–80% of these peptides’ ability to decrease colon adenocarcinoma cell number and
inhibited 92–96% of their DNA synthesis effects and 97% of cyclic GMP’s effects. Western blots revealed that for the first
time natriuretic peptide receptors (NPR) A and C were present in colon adenocarcinoma cells.
Conclusions: Four peptide hormones eliminate up to 97% of colon cancer cells within 24 h with their DNA effects specifically mediated
by cyclic GMP. 相似文献
998.
González V Padilla E Diago M Giménez MD Solà R Matas L Montoliu S Morillas RM Pérez C Planas R 《Journal of viral hepatitis》2005,12(5):481-487
Summary. Early virological response may predict outcome following treatment with peginterferon alpha-2a and ribavirin in patients chronically infected with hepatitis C virus (HCV). As total HCV core antigen may constitute an alternative direct marker to HCV RNA for assessing the levels of viraemia in such patients, we evaluated the correlation between HCV core antigen and HCV RNA, and whether HCV core antigen at baseline, 4 and 12 weeks after treatment could predict sustained virological response (SVR) to combined therapy, in comparison with HCV RNA. A total of 290 serum samples from 58 previously treatment naïve chronic HCV patients were examined for HCV core antigen and HCV-RNA by means of quantitative HCV RNA when receiving combination therapy for the first time. SVR was significantly associated with basal HCV core antigen but not with HCV RNA. There was a good correlation between HCV core antigen and HCV RNA (r2 = 0.781). The negative predictive value of HCV core antigen testing in predicting nonresponse at weeks 4 and 12 were 75 and 100%, and for undetectable or a 2-log drop in HCV RNA were 69.6 and 75% respectively. HCV core antigen detection is quick, and easy to perform alternative to HCV RNA, and could be used as a marker of HCV viraemia for monitoring the progress of therapy. 相似文献
999.
目的检测缓解期老年晚发哮喘(LOA)患者气道反应性和诱导痰嗜酸细胞、嗜酸细胞阳离子蛋白(ECP)和白介素-5(IL-5)水平,探讨其临床意义。方法选择58例缓解期 LOA 患者,测定其气道反应性,并分别采用瑞氏染色、荧光免疫法和酶联免疫吸附试验检测诱导痰中嗜酸细胞数量、ECP 和 IL-5水平;选择25例急性发作期 LOA 患者和15例健康老年人作为对照。结果 58例缓解期 LOA 患者中,49例(84.5%)支气管激发试验阳性,9例(15.5%)阴性。缓解期 LOA 组诱导痰中嗜酸细胞数量[(9.3±3.1)%]、ECP[(144.2±68.1)μg/L]和 IL-5水平[(20.3±6.3)μg/L]显著低于急性发作期 LOA 组[(21.1±9.8)%、(399.3±172.5)μg/L 和(50.6±10.7)μg/L,P<0.01],但显著高于健康老年组[(1.3±0.7)%、(48.7±21.9)μg/L 和(10.3±3.2)μg/L,P<0.01]。气道反应性增高组患者诱导痰中嗜酸细胞数量[(12.7±3.6)%]、ECP[(171.3±69.8)μg/L]和 IL-5水平[(23.6±8.5)μg/L]显著高于气道反应性正常组[(3.1±1.3)%、(52.7±21.1)μg/L 和(13.7±4.1)μg/L,P<0.01]。结论缓解期 LOA 患者多数存在气道高反应性且气道炎症持续存在,测定患者气道反应性和诱导痰中炎性标志物有助于指导缓解期治疗。 相似文献
1000.
Gavin I W Galasko Avijit Lahiri Sophie C Barnes Paul Collinson Roxy Senior 《European heart journal》2005,26(21):2269-2276
AIMS: To define the N-terminal pro-brain natriuretic peptide (NTpBNP) normal range, assessing its cardiovascular screening characteristics in general population and higher risk subjects. METHODS AND RESULTS: A total of 2320 subjects (1392 general population and 928 high-risk) > or =45 years old, selected randomly from seven community practices, were invited to undergo clinical assessment and echocardiography and to assess NTpBNP serum levels. Of these, 1205 attended. The NTpBNP normal range was calculated and its cardiovascular screening characteristics were assessed. Age (P<0.0001) and female gender (P<0.0001) independently predicted NTpBNP levels in normal subjects. In the general population, age- and gender-stratified normal NTpBNP levels gave a negative-predictive value (NPV) of 99% in excluding left ventricular systolic dysfunction, atrial fibrillation, and valvular heart disease, and a positive predictive value of 56% in detecting any cardiovascular disease assessed. In high-risk subjects, these values were 98 and 62%, respectively. Ninety-five per cent of subjects with NTpBNP levels over four times the normal had significant cardiovascular disease with the others having renal dysfunction. CONCLUSION: Normal NTpBNP levels should be stratified by age and gender. Normal NTpBNP levels give high NPV in excluding significant cardiovascular disease. Most subjects with raised NTpBNP levels and almost all subjects with NTpBNP levels over four times the normal have significant cardiovascular disease. 相似文献