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101.
白纹伊蚊和埃及伊蚊defensin A基因克隆及序列分析 总被引:5,自引:0,他引:5
应用PCR技术从白纹伊蚊和埃及伊蚊基因组中扩增出defensinA基因 ,并与文献报道的defensinA的5个型的cDNA序列进行同源性比较 ,发现此两序列中存在内元 ;从埃及伊蚊体内扩增的片段为蚊虫defen sinAl的前体AaDefAl;从白纹伊蚊体内扩增的片段为defensinA的 1个新型 ,命名为DefA6。 相似文献
102.
应用电脑对111例儿童哮喘50项指标进行多因素逐步回归分析,把发作时喘憋严重,平时也有不同程度的喘息症状患儿列入小儿重症哮喘,与非重症哮喘比较,结果显示夜间喘、急性发作持续天数、非特异性刺激诱发、间歇期症状、发绀、呼吸困难、入院后激素治疗、中性粒细胞、IgA、pH、哮喘持续状态等11个因素入选重症哮喘回归方程,表明这些因素与小儿重症哮喘相关,提出儿童哮喘危险信号的临床指标。 相似文献
103.
目的:探讨指背腱膜滑动距离与近侧指间关节(PIP)屈曲关系,为临床修复提供解剖学基础。方法:男性成人新鲜尸体标本10侧30指(示、中、环指各10指),切除手指皮肤,不破坏腱鞘、屈肌支持带、伸肌支持带、内在肌及外在肌,使肌腱保持正常的生理状态,分别测量各指中央束(CS)、侧束(LB)在PIP屈曲45°和90°时的滑动距离。结果:当PIP屈曲45°时,CS滑动距离为(2.7±0.4)mm,LB滑动距离为(2.8±0.6)mm;当PIP屈曲90°时,CS滑动距离为(4.3±0.7)mm,LB滑动距离为(4.8±0.6)mm。结论:指背腱膜滑动距离减少,严重影响手指的屈曲功能。对于指背腱膜的新鲜性损伤应予以精确修复;对于陈旧性损伤的修复应确保指背腱膜的正常滑动范围。 相似文献
104.
本文观察了体外丙二醛(MDA),铜离子(Cu2+氧化修饰的脂蛋白(a)[Lp(a)]结构和生物学性质的变化。氧化修饰Lp(a)过氧化程度增高,负电荷增加,易被巨噬细胞—清道夫受体识别和摄取。MDA修饰Lp(a)出现新的MDA-LDL位点;同纤维蛋白溶酶原(Pg)竞争抑制试验显示氧化、修饰Lp(a)同Pg同源性增加。提示载脂蛋白(a)状态同动脉粥样硬化的病理过程有关。 相似文献
105.
He Z Dong Q Zhuang H Song S Peng G Luo G Dwyer DE 《Clinical and diagnostic laboratory immunology》2004,11(4):792-794
The sensitivities and specificities of an immunofluorescence assay and an enzyme immunoassay for detection of antibodies specific for severe acute respiratory syndrome coronavirus (SARS-CoV) were compared for 148 laboratory-confirmed SARS cases. The appearance and persistence of SARS-CoV-specific antibodies were assessed, with immunoglobulin G detected in 59% of samples collected within 14 days and persisting for 60 to 95 days after the onset of illness. 相似文献
106.
107.
Retrospective analysis of non-A-E hepatitis: possible role of hepatitis B and C virus infection 总被引:6,自引:0,他引:6
He Z Zhuang H Wang X Song S Dong Q Yan J Buehring GC Luo G 《Journal of medical virology》2003,69(1):59-65
In an effort to determine the cause of non-A-E hepatitis, a retrospective study was undertaken on a group of patients with hepatitis but without serological infection markers of hepatitis viruses A-E. A total of 60 patients admitted to Beijing Ditan Hospital during the period of September 1997 and September 1999 were chosen for this study. These patients were diagnosed as either acute or chronic hepatitis, but no serological markers of hepatitis viruses A-E were detected. Since TT virus (TTV), human parvovirus B19 (B19), SEN virus (SENV), and GB virus C/HGV were reported to be associated with hepatitis, attempts were made to detect the presence of these viruses in the sera of patients with non-A-E hepatitis by a nested polymerase chain reaction (nPCR) method. Also, more sensitive nPCR and RT-nPCR methods were used to determine HBV DNA and HCV RNA in these patients. Results derived from these analyses demonstrate that HBV DNA was detected in most of these patients (47/60, 78.3%), suggesting that HBV infection played a major role in occult non-A-E hepatitis and detection of HBV DNA by more sensitive PCR methods such as nPCR should be considered for diagnosis of HBV infection. In addition, HCV RNA was detected in three (5%) of these patients. However, GBV-C (HGV) RNA was not detected, and TTV, B19, and SENV appear not to be associated with non-A-E hepatitis, as the prevalence rates of these viruses in patients with non-A-E hepatitis were similar to those in patients with viral hepatitis A-E. The results from this study indicate that co-infection of TTV or B19 with HBV did not increase the severity of the disease. 相似文献
108.
Analysis of loss of heterozygosity on chromosome 11q13 in atypical ductal hyperplasia and in situ carcinoma of the breast. 总被引:3,自引:2,他引:3
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R. F. Chuaqui Z. Zhuang M. R. Emmert-Buck L. A. Liotta M. J. Merino 《The American journal of pathology》1997,150(1):297-303
Identical allelic loss in invasive and adjacent in situ ductal breast carcinoma (DCIS) on chromosome 11q13 has been previously reported, providing molecular evidence for the progression of DCIS to invasive tumor. In this study we analyzed loss of heterozygosity (LOH) on 11q13 (PYGM, INT-2) in atypical ductal hyperplasia (ADH) and various histological types of in situ carcinomas of the breast in patients without invasive cancer. Twenty-four cases of in situ carcinoma and twelve cases of ADH were studied. Tissue microdissection of normal, hyperplastic, and tumor cells from fixed, paraffin-embedded sections was performed, and DNA was extracted for polymerase chain reaction. In situ tumors included both high- and low-grade DCIS. LOH was identified in six of twenty-two (27.3%) in situ tumors and in one of eleven (9%) ADH cases. Within in situ carcinomas, LOH was identified in six of seventeen (35%) high-grade DCIS but in none of six low-grade DCIS. The present results show that LOH at 11q13 occurs in an appreciable proportion of high-grade DCIS, although the rate is substantially less than in patients with concomitant DCIS and invasive tumor. LOH was identified less frequently in low-grade in situ tumors and ADH, suggesting that a putative tumor suppressor gene(s) located on chromosome 11q13 may be involved in the transition from early preneoplastic lesions to invasive breast cancer. 相似文献
109.
H Zhuang A G Coulepis S A Locarnini J Kaldor J A Marshall I D Gust 《Journal of medical virology》1983,11(4):267-276
During a search for the aetiological agent of non-A non-B hepatitis, a precipitating antigen was detected in the sera of some patients during the acute phase of their illness. The antigen was detected by agar gel diffusion using antibody from convalescent sera obtained from patients with non-A non-B hepatitis, and from haemophiliac sera. The antigen was usually detected early in the patient's illness, disappearing as liver function tests returned to normal. In some patients specific antibody appeared during the convalescent phase of the disease. The antigen does not appear to be specific for non-A non-B hepatitis, as it could be detected with similar frequency in patients with hepatitis A or hepatitis B and some patients with other liver disorders. Biochemical and biophysical studies suggest that the antigen is probably an abnormal lipoprotein produced as a result of acute liver damage. 相似文献
110.
In vitro synergistic effect of minocycline combined with antifungals against Cryptococcus neoformans
Lihua Tan Haiyan Shi Mei Chen Zikuo Wang Zhaoqian Yao Yi Sun 《Journal de Mycologie Médicale》2022,32(1):101227
BackgroundCryptococcus neoformans infections occur in immunocompromised patients, especially those with HIV infection, chemoradiotherapy after cancer, and organ transplantation. Infection can cause pneumonia and meningoencephalitis in severe cases with a high mortality rate if not treated. Although fluconazole and amphotericin B are the first-line treatments for cryptococcosis, the rate of fluconazole resistance has increased significantly due to long-term use. Minocycline is a derivative of tetracycline that exerts its antibacterial effect through inhibition of bacterial protein synthesis. It is also able to pass the blood-brain barrier to act on the central nervous system. The present study investigates the effects of minocycline in combination with antifungals in treating C. neoformans.ObjectiveTo determine in vitro interactions of minocycline combined with itraconazole, voriconazole, posaconazole, fluconazole and amphotericin B against C. neoformans.MethodsThe minimum inhibitory concentrations (MIC) of the antifungals were determined by the CLSI Clinical and Laboratory Standards Institute M27-A3 microdilution method. The in vitro synergistic effects of minocycline combined with itraconazole, voriconazole, posaconazole, fluconazole, and amphotericin B on C. neoformans were detected by the broth microdilution checkerboard technique and disk diffusion testing.Results and ConclusionThe working concentration ranges were 0.125–4 µg/mL for itraconazole, 0.03–0.125 µg/ml for voriconazole, 0.03–1 µg/ml for posaconazole, 0.25–16 µg/ml for fluconazole, and 0.125–2 µg/ml for amphotericin B. The synergistic rates of minocycline combinations against C. neoformans were 55% with itraconazole, 10% with voriconazole, 85% with posaconazole, 20% with fluconazole, and 70% with amphotericin B. The effective MIC value of minocycline in the synergistic combination decreased to 2–32 µg/ml, while the MIC of itraconazole decreased to 0.03–0.125 µg/ml, voriconazole 0.03–0.125 µg/ml, posaconazole 0.03–0.125 µg/ml, 0.125–4 µg/ml fluconazole, and 0.06–0.50 µg/ml amphotericin B. The disk diffusion assay showed that the plates containing minocycline and antifungal drugs produced inhibition zones with diameters larger than the single drug plates. Minocycline showed no antagonistic effect in the combinations. In conclusion, the combination of minocycline and azoles or amphotericin B has synergistic effects against C. neoformans in vitro. 相似文献