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991.
992.
In a study published in the current issue of the Journal of Geriatric Cardiology, Ang and co-investigators used the highresolution 64-slice CT coronary angiography to detect coronary lesions in a group of patients with atypical angina.1 The clinical data of these patients were also used to calculate their risk according the Framingham and PROCAM scoring system.2,3 As the cohort is composed with a majority of low risk patients with atypical angina, only a small minority of the patients were classified as having medium and high risk. The results showed that MDCT uncovered 18% either significant lesions (>50% stenosis) or calcifications (>400Agatston units)in the low risk patients and 33% in the medium and high risk subgroups.…… 相似文献
993.
Fluconazole resistant opportunistic oro-pharyngeal candida and non-candida yeast-like isolates from HIV infected patients attending ARV clinics in Lagos, Nigeria 下载免费PDF全文
CA Enwuru A Ogunledun N Idika NV Enwuru F Ogbonna M Aniedobe A Adeiga 《African health sciences》2008,8(3):142-148
Background
Oro-Pharyngeal Candidiasis (OPC) continues to be considered the most common opportunistic fungal disease in HIV/AIDS patients globally. Azole antifungal agent has become important in the treatment of mucosal candidiasis in HIV patients. Presently, antifungal drug resistance is fast becoming a major problem particularly with the immune depleted population.Objectives
This study was designed to investigate the: existence of OPC, species distribution fluconazole susceptibility profile of yeast cells isolated from oral specimens of HIV/AIDS patients from Lagos Nigeria, between Oct. 2004 and June, 2005.Methodology
The venous blood samples were screened for HIV antibodies using the Cappillus HIV I and II test kit (Trinity Biotech Plc UK), and Genie II HIV I and II EIA kit (Bio-Rad France). The positive results were subsequently confirmed at the laboratory attached to each of the clinics, using the Nigerian Federal Ministry of Health approved algorithm. The samples from 213 (108 females and 105 males) HIV positive patients were plated onto SD agar. The isolates were identified by morphotyping, microscopy and speciated using germ tube test and battery of biochemical sugar fermentation and assimilation tests. Fluconazole agar diffusion susceptibility testing was carried out on each isolates.Results
Seventy-four (34.7%) isolates were recovered including one person with double isolates. Only 70(94.6%) of the isolates could be adequately speciated. Candida albicans 30 (40.5%) was the most frequently isolated species, the rest were non-albicans species, with the frequency of C. tropicalis › C. Krusei › C. glabrata and C. neoformans for species for species having up to 4 isolates. Four (30.8%) out of 13 isolates of C. tropicalis showed germ tube formation. While one C. albicans was germ-tube negative. Out of the 74 isolates tested for fluconazole sensitivity, 58(78.4%) were sensitive, MIC d″ 8µg/ml, 9(12.1%) were susceptible Dose Dependant (SDD), MIC 16–32 µg/ml and 7(9.5%) were resistant, MICs e″ 64µg/ml. Among the C. albicans isolates, 26(86.7%) were sensitive to fluconazole. The rank of susceptibility was C. albicans > C. tropicalis > C. Krusei for the most prevalent species.Conclusion
We conclude that fluconazole resistant strains of oro-pharyngeal yeast-like cells exist in about 9.5% of HIV/AIDS patients with the above stated species distribution. We therefore, highlight the need for routine antifungal susceptibility testing on HIV patients with cases of initial or repeat episodes of OPC. 相似文献994.
Ozer H; George SL; Schiffer CA; Rao K; Rao PN; Wurster-Hill DH; Arthur DD; Powell B; Gottlieb A; Peterson BA 《Blood》1993,82(10):2975-2984
We investigated whether recombinant alpha 2b interferon (r alpha 2bIFN) would reduce the proportion of bone marrow Philadelphia chromosome (Ph) cells in chronic-phase chronic myelogenous leukemia (CML) by treating 107 previously untreated patients daily with r alpha 2bIFN at 5 x 10(6)IU/m2 subcutaneously. Patients with complete remission, partial remission, or partial hematologic remission received treatment until progression; those with progressive disease were taken off study and observed for survival. Sixty-three (59%) of the patients achieved at least a partial hematologic remission (24 complete remissions and 39 partial remissions). The median time to response for the 63 responders was 3.4 months, with a median duration of remission of 52 months and with 81% of responders continuing in remission beyond 12 months. The median survival for the 107 patients was 66 months. Of 78 patients with cytogenetic follow-up data, 31 (40%) achieved a partial cytogenetic response (n = 17) or a complete cytogenetic response (n = 14). The percentage of cytogenetic responders among all patients was 29% (31 of 107 patients). The median time to first cytogenetic response was 9 months. A major dose reduction of r alpha 2bIFN (> or = 50%) was required at some time during treatment in 38% of patients, 26% required 10% to 49% dose reductions, and 36% had minor dose reductions of < or = 10%. No association was observed between dose received and the attainment of a cytogenetic response. None of the usual prognostic factors (sex, race, performance status, weight loss, time from diagnosis to treatment, hepatosplenomegaly, age, symptoms, hemoglobin, or platelet, blast, basophil, or white blood cell count) were significantly related to survival. These data provide confirmation that major cytogenetic responses to prolonged administration of subcutaneous r alpha 2bIFN occur in 20% to 38% (95% confidence interval) of chronic- phase Ph-positive patients. Although it is hypothesized that patients achieving major cytogenetic responses to r alpha 2bIFN should have prolonged remission duration and survival compared with nonresponders, analyses of the effect of cytogenetic responders by both "landmark" and time-dependent covariate techniques fail to provide statistically significant evidence for an effect of cytogenetic response on remission duration or survival. This may be due in part to an effect size insufficiently large to be detected with the number of patients treated in this study. Thus, confirmation of remission duration or survival benefit, if any, of r alpha 2bIFN therapy in Ph-positive chronic-phase CML must await the outcome of randomized trials comparing IFN with conventional agents. 相似文献
995.
目的 探讨应用组蛋白脱乙酰酶抑制剂丙戊酸钠(VPA)调节染色体组蛋白低乙酰化修饰水平对肿瘤细胞增殖周期相关蛋白Cyclin A、Cyclin DI、Cyclin E和P21waf/cipl的调控作用. 方法 应用0.75~4.00 mmol/ VPA干预肝癌细胞HepG2、胃癌细胞BGC-823、乳腺癌细胞MCF-7 48 h后,PI标记流式细胞术检测细胞周期;间接免疫荧光法分析Cyclin A、Cyclin D1、Cyclin E、P21waf/cip1蛋白表达;RT-PCR检测分析Cyclin A、Cyclin D1、Cyclin E、P21waf/cip1 mRNA表达. 结果 HepG2、BGC-823、MCF-7这3种细胞系培养48 h后,流式细胞术分析可见0.75~4.00 mmol/L、VPA实验组随药物浓度的增加而出现逐渐递增的细胞增殖周期G1期阻滞趋势.HepG2、BGC-823细胞Cyclin A蛋白及mRNA表达被明显下调;MCF-7细胞Cyclin A蛋白及mRNA表达在两个浓度组均未见明显变化;Cyclin D1蛋白及mRNA表达在3个细胞系均被明显下调;P21waf/cip1蛋白及mRNA表达在3个细胞均被明显上调;Cyclin E蛋白及mRNA表达则未见明显变化. 结论 应用VPA干预组蛋白乙酰化修饰可对HepG2、BGC-823、MCF-7细胞Cyc-lin D1、P21waf/cip1表达起明显的调控作用;对Cychn A的调控作用则随肿瘤细胞来源及表型的不同而有所差异,而对Cyclin E则无明显的调控作用.在VPA诱导肿瘤细胞增殖周期G1期阻滞过程中,下调CyclinD1和上调P21waf/cip1蛋白及mRNA表达可能是其共同作用途径. 相似文献
996.
目的 探讨腹腔镜下肝门血流阻断在肝切除术(LH)的解剖基础及手术路径。 方法 解剖尸体肝脏,分离血流阻断所涉及各肝门结构,观察在二维平面中毗邻,测量在肝外长度及夹角;观察LH视频中肝门结构,总结镜下的位置及特征。 结果 肝动脉平面低于肝管(90%),肝门静脉分叉位置固定于后方;肝左和肝中静脉在肝外大多共干(90%),肝右静脉与共干间存在间隙,与肝后下腔静脉(IVC)前方相通;肝短静脉位于IVC两侧,有(7±3)支;IVC韧带在尸体中易忽略,活体中较明显,为包绕IVC的膜性结构,厚度个体差异大;各结构在肝外长度及夹角为肝门血流阻断提供足够空间;镜下各结构位置及特征与实体比较有特殊性。 结论 LH中应用肝门血流阻断有解剖依据及路径遵循。 相似文献
997.
GnRH类似物促进人早期胚胎体外发育能力的实验研究 总被引:1,自引:0,他引:1
目的研究促性腺激素释放激素(GnRH)类似物对人类早期胚胎体外发育能力的影响.方法IVF的受精卵进行体外培养.实验一的培养基中,GnRH类似物的浓度分别是0,0.1,0.2,0.5,0.8和1.0μg/mL;实验二的培养基中都含有0.5μg/mL的GnRH类似物,而GnRH拮抗剂的浓度分别为0,0.2,0.4,0.8,1.0和1.2μg/mL.结果培养基中的GnRH类似物浓度在0.5μg/mL及以上时,实验组的桑椹胚/囊胚生成率显著高于对照组(P〈0.05),而且,实验组的8-细胞期胚胎形成率也同时显著高于对照组(P〈0.05).培养基中含0.8μg/mL及以上浓度的GnRH拮抗剂时,实验组的桑椹胚/囊胚生成率显著低于对照组(P〈0.05),而且8-细胞期胚胎形成率也显著降低(P〈0.05).结论GnRH类似物对体外培养的人早期胚胎有促进分裂的作用,这种促进早期胚胎发育的效果在8-细胞期就能显现出来.GnRH拮抗剂能抵消GnRH类似物对早期胚胎发育的促进效果. 相似文献
998.
999.
目的 探讨高气压暴露对大鼠血浆内皮素-1(endothelin-1,ET-1)含量、血清一氧化氮(nitric oxide,NO)含量、一氧化氮合酶(nitric oxide synthase,NOS)活性的影响.方法 40只SD大鼠随机分为5组.A组为对照组,B组0.7 MPa空气暴露后缓慢减压,C组0.7 MPa空气暴露后快速减压,D组0.147 MPa纯氧暴露后减压,E组0.250 MPa纯氧暴露后减压.各组暴露时间均为60 min.采用放射免疫方法测定血浆ET-1含量,硝酸还原酶法测定血清NO含量,比色法测定血清NOS活性.结果 与对照组相比,安全减压组和高压氧组的血浆ET-1含量明显升高(P<0.05),原因可能与高分压氧有关(PO2=0.147 MPa/0.250 MPa);快速减压组血清NO含量、NOS活性明显升高(P<0.05),与血浆ET-1含量升高的3个组相比,血清NO、NOS升高得更为显著(P<0.01).结论 NO与ET-1在机体对高气压暴露的反应中呈拮抗关系.高气压与高压氧暴露导致血浆ET-1的释放增加,但快速减压刺激血管内皮细胞产生更多的NO,这种机制可能是通过提高血浆中的NOS活性实现的,这个现象可能是血管内皮系统对血管内气泡产生的应激性反应之一. 相似文献
1000.
Bronchioloalveolar carcinoma: a review 总被引:11,自引:0,他引:11
The radiographs of 136 patients with bronchioloalveolar carcinoma were reviewed. The varied radiographic manifestations were a result of the characteristic peripheral location of the tumor, its tendency to infiltrate the local airways with mucus production and desmoplasia, and its variable aggressiveness resulting in a wide variation in rate of intrathoracic and extrathoracic spread. In the absence of surgical intervention, a localized lesion progressed to diffuse disease in every patient. The findings supported the concept of bronchioloalveolar carcinoma as a distinct clinical entity. 相似文献