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991.
丙型肝炎病毒基因分型及其与干扰素治疗应答的关系 总被引:4,自引:0,他引:4
目的为了解山西省丙型肝炎病毒的基因型和基因型对干扰素疗效的预示价值。方法用HCV5’NC区酶切分型方法对94例丙型肝炎病人进行基因分型,并观察其中45例患者对干扰素α1b治疗的应答。结果显示HCVⅠ组(Ⅰ、Ⅱ型)感染80例(851%),HCVⅡ组(Ⅲ、Ⅳ型)感染12例(128%),HCVⅠ/Ⅱ组混合感染2例(21%)。在接受干扰素治疗的病例中,HCVⅠ组感染(35例)的应答率为371%,持续应答率为171%,而Ⅱ组感染(10例)的应答率为80%,持续应答率为60%,两组相比,有显著性差异(P<005,P<0025)。结论表明山西省以HCVⅠ组感染为主,干扰素对HCVⅡ组感染的疗效优于HCVⅠ组感染,HCV基因型有预测干扰素疗效的意义。 相似文献
992.
It has been suggested that immune responses are involved in the development of atherosclerosis. We have evaluated this possibility by analyzing immunocompetent cells in a murine model of the disease. Apolipoprotein E knockout (apoE -/-) mice are genetically hypercholesterolemic due to targeted disruption of the apolipoprotein E gene and develop severe atherosclerosis. Such mice were fed either standard pellets or a diet containing 1.25% cholesterol. Lesions were analyzed from mice at 9 and 16 weeks of age. Immunohistochemical staining of fatty streaks showed that CD4+ T cells were frequent, both in clusters and as single cells. In advanced atherosclerotic plaques, CD4+ T cells were prominent in the fibrous cap and subendotbelially, whereas CD8+ T cells were sparse. The CD25 subunit of the interleukin-2 receptor, which is a marker for activated T cells, was expressed in CD4-rich areas and the major histocompatibility complex class II antigen, I-A(b), which is induced by cytokines released from activated T cells, was also found in the lesions. These data indicate that CD4+ T cells participate in the formation of atherosclerotic lesions in genetically hypercholesterolemic apoE -/- mice. They suggest that immune activation is part of the disease process, and we speculate that a direct link may exist between cholesterol accumulation and T cell activation, possibly by autoimmune responses to modified lipoproteins. 相似文献
993.
Mycoplasma hyopneumoniae increases intracellular calcium release in porcine ciliated tracheal cells
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Park SC Yibchok-Anun S Cheng H Young TF Thacker EL Minion FC Ross RF Hsu WH 《Infection and immunity》2002,70(5):2502-2506
We investigated the effects of intact pathogenic Mycoplasma hyopneumoniae, nonpathogenic M. hyopneumoniae, and Mycoplasma flocculare on intracellular free Ca2+ concentrations ([Ca2+]i) in porcine ciliated tracheal epithelial cells. The ciliated epithelial cells had basal [Ca2+]i of 103 +/- 3 nM (n = 217 cells). The [Ca2+]i increased by 250 +/- 19 nM (n = 47 cells) from the basal level within 100 s of the addition of pathogenic M. hyopneumoniae strain 91-3 (300 microg/ml), and this increase lasted approximately 60 s. In contrast, nonpathogenic M. hyopneumoniae and M. flocculare at concentrations of 300 microg/ml failed to increase [Ca2+]i. In Ca2+-free medium, pathogenic M. hyopneumoniae still increased [Ca2+]i in tracheal cells. Pretreatment with thapsigargin (1 microM for 30 min), which depleted the Ca2+ store in the endoplasmic reticulum, abolished the effect of M. hyoneumoniae. Pretreatment with pertussis toxin (100 ng/ml for 3 h) or U-73122 (2 microM for 100 s), an inhibitor of phospholipase C, also abolished the effect of M. hyopneumoniae. The administration of mastoparan 7, an activator of pertussis toxin-sensitive proteins G(i) and G(o), increased [Ca2+]i in ciliated tracheal cells. These results suggest that pathogenic M. hyopneumoniae activates receptors that are coupled to G(i) or G(o), which in turn activates a phospholipase C pathway, thereby releasing Ca2+ from the endoplasmic reticulum. Thus, an increase in Ca2+ may serve as a signal for the pathogenesis of M. hyopneumoniae. 相似文献
994.
18例恶性苗勒混合瘤临床病理分析 总被引:1,自引:0,他引:1
目的:探讨女性生殖系统恶性苗勒混合瘤(MMMT)的临床与病理特征。方法:对18例女性生殖系统MMMT进行光镜观察及免疫组化染色,结合临床资料进行分析,对9例进行了术后随访。结果:各部位MMMT的形态特征相似,均含有上皮及间叶两种组织成分,相互间有穿插和移行变化,组织成分形态多样,免疫组化有助于判断。恶性度与异型性、核分裂数及出血坏死程度有关。预后与临床分期有关。化疗有效。结论:MMMT的诊断主要依据组织形态学,预后与临床分期有关。 相似文献
995.
从临床收集耐亚胺培南的铜绿假单胞菌和鲍曼不动杆菌共50株,进行头孢他啶和2-巯基乙醇的表型协同试验(CAZ ME),然后进行金属酶IMP-1基因的PCR检测。选取IMP-1阳性株测序,用PCR方法检测有无一类整合子基因(IntI1)。表型的检测发现有28株为协同阳性,其中铜绿假单胞菌27株,鲍曼不动杆菌1株。PCR和测序检测出其中一株铜绿假单胞菌含有IMP-1基因,同时也含有IntI1基因。首次在中国西部地区发现产IMP-1型金属酶、同时也含有一类整合子的铜绿假单胞菌,对于临床上研究细菌的耐药性传播具有重要意义。 相似文献
996.
PCR based mutation screening of the laminin alpha2 chain gene (LAMA2): application to prenatal diagnosis and search for founder effects in congenital muscular dystrophy. 总被引:1,自引:0,他引:1
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P Guicheney N Vignier X Zhang Y He C Cruaud V Frey A Helbling-Leclerc P Richard B Estournet L Merlini H Topaloglu M Mora J P Harpey C A Haenggeli A Barois B Hainque K Schwartz F M Tomé M Fardeau K Tryggvason 《Journal of medical genetics》1998,35(3):211-217
Classical congenital muscular dystrophy with merosin deficiency is caused by mutations in the laminin alpha2 chain gene (LAMA2). Extended sequencing of the introns flanking the 64 LAMA2 exons was carried out and, based on these sequences, oligonucleotide primers were designed to amplify the coding region of each exon separately. By PCR-SSCP analysis, we identified eight new mutations in nine families originating from various countries. All induced a premature truncation of the protein, either in the short arm or in the globular C-terminal domain. A 2 bp deletion in exon 13, 2098delAG, was found in three French non-consanguineous families and a nonsense mutation of exon 20, Cys967stop, in two other non-consanguineous families originating from Italy. Determination of rare intragenic polymorphisms permitted us to show evidence of founder effects for these two mutations suggesting a remote degree of consanguinity between the families. Other, more frequent polymorphisms, G to A 1905 (exon 12), A to G 2848 (exon 19), A to G 5551 (exon 37), and G to A 6286 (exon 42), were used as intragenic markers for prenatal diagnosis. This study provides valuable methods for determining the molecular defects in LAMA2 causing merosin deficient congenital muscular dystrophy. 相似文献
997.
Rapid non-genomic inhibitory effects of glucocorticoids on human neutrophil degranulation 总被引:4,自引:0,他引:4
L. Liu Y. X. Wang J. Zhou F. Long H. W. Sun Y. Liu Y. Z. Chen C. L. Jiang 《Inflammation research》2005,54(1):37-41
Background: Glucocorticoids acting as anti-inflammatory or immunosuppressive drugs have been shown to exert most of their effects genomically. Recent findings suggest that non-genomic activity might be relatively more important in mediating the therapeutic effects of high-dose pulsed glucocorticoid. However, few non-genomic anti-inflammatory effects were reported, much less non-genomic mechanisms.Objective: This study was performed to investigate the nongenomic effects of glucocorticoids on human neutrophil degranulation.Methods: Purified human neutrophils were pretreated with 6 -methylprednisolone or hydrocortisone for 5 min, and then primed with N-formyl-methionyl-leucyl-phenylalanine (fMLP) (10–6 M) or phorbol myristate acetate (PMA) (50 ng/ml) in the presence of cytochalasin B. The release of two markers of neutrophil granules, lactoferrin and myeloperoxidase, was measured by ELISA and enzymology methods respectively.Results: Both 6 -methylprednisolone (10–5–10–4 M) and hydrocortisone (10–4 M) showed significant inhibitory effects on neutrophil degranulation within 5 min after fMLP administration. For PMA stimulated degranulation, 6 -methylprednisolone (10–4 M) showed significant inhibitory effects (p < 0.01), while hydrocortisone (10–4 M) only showed an inhibitory tendency (P > 0.05). Neither RU486 (10–5 M) nor cycloheximide (10–4 M) could alter the inhibitory effects of glucocorticoids.Conclusion: Our results demonstrate that megadoses of glucocorticoids exert rapid inhibitory effects on human neutrophil degranulation at the cellular level via a new mechanism that is independent of corticosteroid type II receptor occupation or protein synthesis. We infer that these effects may be very important when glucocorticoids act as anti-inflammatory drugs during pulse therapy.Received 20 May 2004; returned for revision 21 July 2004; accepted by M.J. Parnham 23 September 2004L. Liu and Y. X. Wang contributed equally to this work. 相似文献
998.
目的探讨晚期氧化蛋白(AOPP)在急性有机磷农药中毒(AOPP)患者中的临床意义。方法采用酶联免疫分析法(ELISA)动态检测90例有机磷农药中毒患者和30例健康对照者血清晚期氧化蛋白的含量,并探讨其与病情的相关性。结果AOPP患者血浆中晚期氧化蛋白含量发病后的第1天〉第3天〉第7天与健康对照组比较,P均〈0.01。血清CRP的含量在患者中毒后的第1天〉第3天〉第7天与健康对照组比较,P均〈0.01。在发病的第1天,AOPP患者血清晚期氧化蛋白和CRP的含量重度中毒组〉中度中毒组〉轻度中毒组与健康对照组比较,P均〈0.01。在第1天,AOPP患者的病情程度即MODS的评分值与血清晚期氧化蛋白和CRP的含量均呈明显的正相关性(r1=0.590和r2=0.627,P均〈O.01),而血清晚期氧化蛋白和CRP的含量之间也呈明显的正相关性(r3=0.792,P〈0.01)。结论晚期氧化蛋白的含量随急性有机磷农药中毒患者的病情和炎症反应加重而升高。晚期氧化蛋白可能参与了有机磷农药中毒患者发生多脏器功能障碍的病理生理过程。 相似文献
999.
Temporal information in the responses of auditory neurons to sustained sounds has been studied mostly with periodic stimuli, using measures that are based on Fourier analysis. Less information is available on temporal aspects of responses to nonperiodic wideband sounds. We recorded responses to a reference Gaussian noise and its polarity-inverted version in the auditory nerve of barbiturate-anesthetized cats and used shuffled autocorrelograms (SACs) to quantify spike timing. Two metrics were extracted from the central peak of autocorrelograms: the peak-height and the width at halfheight. Temporal information related to stimulus fine-structure was isolated from that to envelope by subtracting or adding responses to the reference and inverted noise. Peak-height and halfwidth generally behaved as expected from the existing body of data on phase-locking to pure tones and sinusoidally amplitude-modulated tones but showed some surprises as well. Compared with synchronization to low-frequency tones, SACs reveal large differences in temporal behavior between the different classes of nerve fibers (based on spontaneous rate) as well as a strong dependence on characteristic frequency (CF) throughout the phase-locking range. SACs also reveal a larger temporal consistency (i.e., tendency to discharge at the same point in time on repeated presentation of the same stimulus) in the responses to the stochastic noise stimulus than in the responses to periodic tones. Responses at high CFs reflect envelope phase-locking and are consistent with previous reports using sinusoidal AM. We conclude that the combined use of broadband noise and SAC analysis allow a more general characterization of temporal behavior than periodic stimuli and Fourier analysis. 相似文献
1000.
T cell death and transplantation tolerance 总被引:15,自引:0,他引:15