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81.
Ching-Yu Lin Angel Chao Yuh-Cheng Yang Hung-Hsueh Chou Chih-Ming Ho Ruey-Wen Lin Ting-Chang Chang Jia-Yia Chiou Fang-Yu Chao Kung-Liahng Wang Tsai-Yen Chien Swei Hsueh Chu-Chun Huang Chien-Jen Chen Chyong-Huey Lai 《Journal of clinical virology》2008,42(4):361-367
BACKGROUND: Type-specific persistence of human papillomavirus (HPV) infection can cause invasive cervical cancer. OBJECTIVES: To evaluate the efficacy of HPV detection and typing with a general polymerase chain reaction (PCR)-based genotyping array and to compare it with a type-specific PCR assay. STUDY DESIGN: Four hundred and thirty-three cervical samples were tested with a modified MY11/GP6+ PCR-based reverse-blot assay (EasyChip HPV Blot; King Car, Taiwan [hereafter HPV Blot]) and with 20 genotypes of L1-type-specific PCR (HPV-6, -11, -16, -18, -31, -33, -35, -39, -45, -51, -52, -53, -56, -58, -59, -62, -66, -68, -70, and -71 [CP8061]). RESULTS: The concordance of the two tests in determining HPV positivity was 96.8% (419/433), with a Cohen's kappa=0.93 (95% CI: 0.90-0.97) and McNemar's test of P=1.0, which indicates excellent agreement. The overall concordance of the two tests in the identification of type-specific HPV was 91.0% (394/433). Sensitivity (90-100%), specificity (99.2-100%), and accuracy (98.6-100%) rates of HPV Blot against the gold standard were satisfactory for HPV-16, -18, -58, -33, -52, -39, -45, -31, -51, -70 while HPV-71 (63.6%) had suboptimal sensitivity. Though the kappa values between the two tests for many individual genotypes could not be reliably calculated because of low positivity, the kappa values for HPV-16, -52, and -58 were excellent (0.93, 0.96, and 0.95, respectively). CONCLUSION: The modified MY11/GP6+ PCR-based HPV Blot assay is accurate and sensitive for detection and genotyping of HPV in cervical swab samples. 相似文献
82.
Su SC Chou SS Chang PC Hwang DF 《Journal of chromatography. B, Biomedical sciences and applications》2000,749(2):163-169
A micellar electrokinetic capillary chromatography (MECC) method for the simultaneous determination of seven biogenic amines in fish was developed. The peaks of all components were successfully separated within 11.5 min. MECC was performed with 0.06 M sodium deoxycholate in 0.02 M borate buffer (pH 9.2)-methanol (95:5, v/v) solvent. The average recoveries for all components ranged from 84.4 to 100.3%. The application of this method to detect amines in fried marlin fillet implicated in a food poisoning incident indicated that a high level (56.24 mg/100 g) of histamine was present in the sample. Another 10 fish samples collected from markets were also analyzed and did not contain detectable levels of histamine (<2.5 mg/100 g). 相似文献
83.
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85.
Antibody against Epstein-Barr virus DNA polymerase activity in sera of patients with nasopharyngeal carcinoma 总被引:1,自引:0,他引:1
A salt-dependent DNA polymerase activity was demonstrated in the culture of an EBV-producing, lymphoblastoid cell line (NPC-204 cells) treated with 5-iodo-2'-deoxyuridine (IUdR). There was a high frequency of levels of antibody to this enzyme in sera of patients with nasopharyngeal carcinoma (NPC). In contrast, sera from healthy subjects had little or no neutralizing activity. The high antibody level appeared as early as stage 1 of the disease in many NPC patients. The levels of the antibody increased with the progression of the disease and declined in treated patients. The results strongly suggest that tests measuring serum antibody against EBV DNA polymerase activity can be used for early diagnosis and prognosis of NPC. 相似文献
86.
Vandenbark AA Barnes D Finn T Bourdette DN Whitham R Robey I Kaleeba J Bebo BF Miller SD Offner H Chou YK 《International immunology》2000,12(1):57-66
Antigen-coupled antigen-presenting cells (APC) serve as potent tolerogens for inhibiting immune responses in vivo and in vitro, apparently by providing an antigen-specific signal through the TCR in the absence of co-stimulation. Although this approach has been well studied in rodents, little is known about its effects on human T cells. We evaluated the specificity and mechanisms of tolerization of human T cells in vitro using monocyte-enriched adherent cells that were pulsed with antigen and treated with the cross-linker, 1-ethyl-3-(3-dimethylaminopropyl)-carbodiimide (ECDI). Autologous antigen-coupled APC selectively tolerized T cells of the T(h)1 but not T(h)2 lineage through a mechanism that involved both antigen-specific and antigen-non-specific elements. The tolerization process was dependent on the ECDI and antigen concentration, and the coupling time, and was reflected by initial up-regulation of CD25. However, upon re-stimulation with fresh APC and antigen, tolerized T(h)1 cells failed to proliferate or to produce T(h)1 cytokine message or secreted protein, had decreased expression of CD25, CD28 and B7 and increased expression of MHC class II molecules, and demonstrated an enhanced commitment to apoptosis. T(h)1 cell tolerization could be prevented by adding anti-CD28 antibody, IL-2 or untreated APC at the same time as the ECDI/antigen-coupled APC, or reversed by adding anti-CD28 antibody or IL-2 upon re-stimulation with fresh APC plus antigen. Thus, the tolerizing effect of ECDI/antigen-coupled APC on human T(h)1 cells appears to involve a reversible anergy mechanism leading to apoptosis, whereby the targeted T cells receive full or partial activation through the TCR, without coordinate co-stimulation. These data suggest dichotomous signaling requirements for inactivating cells of the T(h)1 and T(h)2 lineages that may have important implications for treatment of T(h)1-mediated autoimmune or inflammatory diseases. 相似文献
87.
Inconsistent effects of all-trans retinoic acid on different clones of chemically transformed rat liver epithelial cells 总被引:1,自引:0,他引:1
Tsao Ming-Sound; Blaisdell Joyce; Chou Barbara B.; Earp H.Shelton; Grisham Joe W. 《Carcinogenesis》1987,8(4):497-501
The effects of all-trans retinoic acid (RA) on the growth andbiochemical properties of five clonal strains of neoplasticallytransformed rat liver epithelial cells were studied. These cellstrains were derived clonally from a single line of normal diploidrat liver epithelial cells that had been transformed by treatmentwith N-methyl-N'-nitro-N-nitrosoguanidine. The results showthat RA induces inconsistent alterations in selected phenotypicproperties of these five different cell strains. Retinoic acideither depressed, enhanced or produced no effect on the colony-formingability in soft agar, on the activity of -glutamyl transpeptidase,on the amount of cell-associated fibronectin, and on the bindingcapacity of 125I-epidermal growth factor (EGF). The only consistentcorrelation observed among cell strains was between the cellularability to grow in soft agar and the amount of cell-associatedfibronectin. Enhancement of anchorage-independent growth byretinoic acid was not mediated through changes in the numberof EGF receptors. Our data demonstrate that the responses toretinoic acid of clonal subpopulations of chemically transformedrat liver epithelial cells are inconsistent, even when the clonalsubpopulations are derived from a common precursor. 相似文献
88.
The term "cytoplasmic body" or "spheroid body" myopathy refers to a heterogeneous group of familial or sporadic diseases characterized primarily by the presence of abundant spheroid or cytoplasmic bodies in the muscles. The morphogenesis of these inclusions remains unclear. This article describes the induction and evolution of spheroid cytoplasmic bodies (SCBs) in the rat plantaris muscle (PL) with local tetanus, which was induced in rats by the injection of a minute amount of tetanus toxin. In contrast to the tetanized soleus muscle (SOL), which developed core fibers (central cores, minicore, target fiber, targetoid fiber, and rods), the tetanized PL produced numerous SCBs with a predictable time course. They were induced in both type 1 and 2 fibers of PL, which is composed predominantly (95%) of type 2 fibers, in contrast to SOL (85% type 1 fibers). Factors inducing SCBs may include immobilization, shortening, intact innervation, and disuse atrophy. 相似文献
89.
In a series of experiments, we investigated the effects of pulsed low-level microwave irradiation on amphetamine-induced hyperthermia in the rat. Rats were irradiated in a 2,450-MHz cylindrical waveguide exposure system at 1 mW/cm2, 2 s pulses, 500 pps, average SAR of 0.6 W/kg. Acute (45 min) exposure to microwaves attenuated amphetamine-induced hyperthermia. This effect was blocked by pretreatment of the animals with the narcotic antagonist naloxone. In another experiment, rats were subjected to ten daily sessions of microwave exposure (45 min/session). On day 11, amphetamine-induced hyperthermia was studied in the animals immediately after a session of either microwave or sham exposure. Similar to the acute effect, amphetamine-induced hyperthermia was attenuated in rats irradiated with microwaves (unconditioned effect). In the sham-irradiated animals we observed a potentiation of the amphetamine-induced hyperthermia, which was a conditioned effect of microwaves. Thus, the conditioned effect (potentiation) was opposite in direction to the unconditioned effect (attenuation). No tolerance developed to the unconditioned effect after subchronic exposure. Furthermore, both conditioned and unconditioned effects of microwaves on amphetamine-induced hyperthermia could be blocked by treatment with naloxone. These data suggest that (1) microwave irradiation may activate endogenous opioids, which in turn alter the actions of psychoactive drugs, and (2) the effect of microwaves on drug action can be classically conditioned.
Offprint requests to: H. Lai 相似文献
90.
目的构建列线图模型以预测新型冠状病毒病2019(COVID-19)的死亡风险,以早期筛选死亡高危患者。 方法收集2020年1月至2020年4月武汉大学人民医院(东院)和2022年4月至2022年5月上海市第九人民医院(北院)收治COVID-19患者的临床资料。以武汉大学人民医院患者(166例)作为训练集,上海市第九人民医院患者(52例)作为验证集。采用先单因素后多因素Logistic回归分析确定死亡的独立危险因素,应用R语言构建列线图模型。采用受试者工作特征曲线(ROC)、C指数及校准曲线评估列线图模型的预测准确性及判断能力,决策曲线分析评估模型的临床应用价值。通过验证集对模型进行外部验证。 结果本研究共纳入重型/危重型COVID-19患者218例,其中67例(30.73%)死亡,多因素Logistic回归分析显示,≥3种基础疾病、APACHE Ⅱ评分(5~40分)、中性粒细胞/淋巴细胞(0~90)、乳酸(0~16mmol/L)均是死亡的独立危险因素。ROC曲线分析显示,训练集的曲线下面积(AUC)为0.869(95%CI:0.811~0.927),验证集AUC为0.797(95%CI:0.671~0.924),训练集与验证集校准曲线经Hosmer-Lemeshow拟合优度检验(P=0.473,P=0.421)。临床决策曲线分析表明,该列线图预测模型的临床应用价值高。 结论本研究构建COVID-19患者死亡风险列线图模型预测效能良好,可个体化、可视化、图形化预测,有助于医师早期做出合适临床决策及诊疗。 相似文献