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41.
Yasuhiro Sano Shigeharu Yamashiro Asuka Komano Hisashi Maruko Hiroshi Sekiguchi Yasuo Takayama Ryoji Sekioka Kouichiro Tsuge Isaac Ohsawa Mieko Kanamori-Kataoka Yasuo Seto Akiyoshi Satoh 《Forensic Toxicology》2007,25(2):76-79
We previously reported that the Guardian Bio-Threat Alert (BTA) system could detect (detection limit: about 0.1 μg/ml) staphylococcal
enterotoxin B (SEB), botulinum toxins (BTX) A and B, and ricin, with no interference by white-powdered materials or colored
matrices. In this study, the capability of the BTA system was further assessed. With 10 min of preheating at 60°C, all toxins
could be detected, but with preheating at 80°C, BTX A and B and ricin became undetectable. About 20% SEB could be detected
after heating at 80°C, but this detection ability was completely removed after heating at 100°C. The effects of chemicals
usually used for decontamination, such as sodium hypochlorite, hydrogen peroxide, formaldehyde, and sodium nitrite, on the
detectability of SEB, BTX A, or ricin in the BTA system were also tested. The concentrations giving 50% line intensity for
SEB, BTX A, and ricin were 3.1, 11, and 15 μM for sodium hypochlorite and 88, 210, and 60 mM for formaldehyde, respectively.
The addition of hydrogen peroxide or sodium nitrite did not decrease the detectability even when used at high concentrations. 相似文献
42.
目的观察WGLY-801型电脑肝病治疗仪对慢性乙型肝炎的治疗效果。方法随机选取慢性乙型肝炎患者144例,分为治疗组66例,在常规治疗基础上加用肝病治疗仪;对照组78例,采用常规治疗,观察两组治疗效果。治疗三疗程共45天(每疗程15天),观察临床症状、肝功能的动态变化,并对最终效果进行评价。结果经治疗后,两组患者临床症状、肝功能较前均有好转,但治疗组起效快,疗程明显缩短,疗效好,差异有明显统计学意义(p<0.05)。结论肝病治疗仪,操作简单,疗效确切,值得进一步推广应用。 相似文献
43.
Eran Maman David M. Steinberg Batia Stark Shai Izraeli Shlomo Wientroub 《Journal of children's orthopaedics》2007,1(1):63-68
Purpose Studies on musculoskeletal manifestations (MSM) of childhood acute lymphoblastic leukemia (ALL) have yielded variable findings
with regard to their clinical impact. We investigated the significance for differential diagnosis, treatment and outcome of
musculoskeletal complaints as presenting symptoms of ALL, and their correlation with leukemia immunophenotypes, for which
data is lacking.
Methods Data on 783 children in the national study for childhood ALL between 1984 and 2003 were reviewed retrospectively. Statistical
analysis examined possible relationships between MSM at the time of diagnosis and demographic and clinical data, biological
features of leukemia (peripheral blood counts, immunophenotype and main cytogenetic aberration), response to initial prednisone
treatment, and outcome.
Results Of 765 children with data on orthopaedic complaints, 240 presented with MSM (31.4%). Among these children, B cell precursor
(BCP) was much more common (209/576, 36.3%) than T cell ALL (25/176, 14.2%). Patients with MSM had lower white blood cell
counts (WBC) (median of 9 vs. 20 × 109/L, P < 0.001) and percentage of blast cells in the peripheral blood at diagnosis compared to those without (median of 27 vs. 53%,
P < 0.001). Hepatomegaly and splenomegaly were less common in MSM group (67 vs. 53% <3 cm, P < 0.001, and 63 vs. 50% <3 cm, P < 0.001, respectively). Poor response to initial treatment with prednisone was recorded in 7.1% of patients with MSM versus
11.5% of those without (P = 0.086). The analysis revealed no independent effect of MSM on event-free survival (EFS), after correcting for differences
in EFS related to immunophenotype or initial WBC.
Conclusions MSM occur mostly in children with BCP ALL who present with less involvement of extramedullary organs, low peripheral blood
blasts and white blood cells counts. These findings highlight the importance of including ALL in the differential diagnosis
of MSM even in the presence of an apparently normal peripheral blood count. Our study also suggests that MSM are caused by
leukemic cells with enhanced biological propensity to remain relatively confined within the intramedullary bone-marrow space. 相似文献
44.
A. L. Snow M. Vaysberg S. M. Krams O. M. Martinez 《American journal of transplantation》2006,6(5P1):976-985
Lymphomas associated with post-transplant lymphoproliferative disease (PTLD) represent a significant complication of immunosuppression in transplant recipients. In immunocompetent individuals, EBV-specific cytotoxic T lymphocytes (CTL) prevent the outgrowth of activated B lymphoblasts through apoptosis induction. Soluble versions of TNF-related apoptosis-inducing ligand/Apo2 ligand (TRAIL) can induce apoptosis in numerous tumor cell types. Given the therapeutic potential of TRAIL, we examined the sensitivity of EBV+ spontaneous lymphoblastoid cell lines (SLCL) derived from patients with PTLD to treatment with soluble TRAIL. Despite abundant expression of TRAIL receptors (TRAIL-R), resistance to TRAIL-induced apoptosis was observed in all SLCL examined. This resistance could not be overcome by concomitant treatment with several pharmacological agents. Unlike BJAB positive control cells, for each SLCL tested, cleavage and activation of caspase 8 was inhibited due to failed recruitment of FADD and caspase 8 to TRAIL receptors upon stimulation. Further indicative of a proximal defect, TRAIL receptor aggregation could not be detected on the cell surface of SLCL following ligand engagement. These results suggest that the use of TRAIL for eliminating PTLD-associated tumors may be of limited clinical utility, and illustrate another mechanism by which EBV+ B lymphoma cells can evade tumor surveillance at the level of death receptor signaling. 相似文献
45.
The pathomechanisms involved in the neuronal dysfunction in Huntington disease (HD) are still unresolved and may be heterogeneous. One potential mechanism might be related to the induction of mitochondrial dysfunction in the CNS. This might lead firstly to neuronal dysfunction and finally to the activation of apoptotic pathways. Several compounds, which should alleviate mitochondrial dysfunction, have been tested in preclinical models as well as in clinical trials of different scale. Recently we reported the efficacy of Ethyl-eicosapentaenoic acid (Ethyl-EPA) in patients with HD. Ethyl-EPA is a polyunsaturated fatty acid from the n − 3 group, which is in clinical development for HD and melancholic depression. In our trial with Ethyl-EPA in HD responding patients could be characterized by either a lower CAG repeat number or a chorea-predominant clinical expression of the disease. Here we would like to describe some evidence on the potential mechanism of action of Ethyl-EPA in HD. We specifically focus on pathways, which are known to be influenced in HD and are modified by Ethyl-EPA and which points to an involvement of mitochondrial function as a common target. Some attention is given to the NF-kappa B pathway and the c-Jun amino-terminal kinases (JNK) pathway, which both may lead to an activation of the antiproliferative factor p53 and consequently mitochondrial dysfunction. Further the effects of EPA or Ethyl-EPA in preclinical models of HD are described. The evidence from these studies led to the design of phase III clinical trials, which are ongoing. 相似文献
46.
Jan Petr Jan Kybic Michael Bock Sven Müller Václav Hlavác 《Magnetic resonance in medicine》2007,58(3):582-591
A new reconstruction method for parallel MRI called PROBER is proposed. The method PROBER works in an image domain similar to methods based on Sensitivity Encoding (SENSE). However, unlike SENSE, which first estimates the spatial sensitivity maps, PROBER approximates the reconstruction coefficients directly by B-splines. Also, B-spline coefficients are estimated at once in order to minimize the reconstruction error instead of estimating the reconstruction in each pixel independently (as in SENSE). This makes the method robust to noise in reference images. No presmoothing of reference images is necessary. The number of estimated parameters is reduced, which speeds up the estimation process. PROBER was tested on simulated, phantom, and in vivo data. The results are compared with commercial implementations of the algorithms SENSE and GRAPPA (Generalized Autocalibrating Partially Parallel Acquisitions) in terms of elapsed time and reconstruction quality. The experiments showed that PROBER is faster than GRAPPA and SENSE for images wider than 150x150 pixels for comparable reconstruction quality. With more basis functions, PROBER outperforms both SENSE and GRAPPA in reconstruction quality at the cost of slightly increased computational time. 相似文献
47.
A Gerritzen H Brackmann B van Loo G Nies C Ruland G Spiegelberg U Hammerstein 《Journal of medical virology》1991,34(3):188-190
The seroepidemiological profile of HBV and HDV was investigated in 640 male haemophiliacs. Twenty-seven of forty-four HBsAg carriers were anti-HDV-IgG positive, 22 were also anti-HDV-IgM positive. A markedly lower prevalence of HDV infection was found in patients with anti-HBc in the absence of HBsAg and anti-HBs (6/41). Repeated detection of anti-HDV-IgM in 5/41 individuals of this group indicates that circulating HBsAg is not an absolute prerequisite for chronic HDV infection. Overall, chronically active HDV infection was detected more frequently in quiescent than in active chronic HBV infections. Anti-HDV-IgM was not detected in the absence of anti-HDV-IgG antibodies. Anti-HDV-IgG may disappear after resolution of HDV infection, as indicated by the low prevalence (1/42) in such individuals with past HBV infection as well as by loss of anti-HDV-IgG observed in two patients. 相似文献
48.
Abstract The outcome of OLT for HBV-related liver disease is dependent on the prevention of allograft re-infection. Over the past decade, major advances have been made in the management of HBV transplant candidates. The advent of long-term hepatitis B immune globulin (HBIG) administration as a prophylaxis against HBV recurrence, and the introduction of new antiviral agents against HBV infection, such as lamivudine (LAM), were a major breakthrough in the management of these patients. Results of OLT for HBV infection are similar to those achieved with other indications. Pre-OLT antiviral treatment such as LAM can suppress HBV replication before OLT and thus decrease the risk of re-infection of the graft. Combination prophylaxis with LAM and HBIG after transplantation highly effectively reduces the rate of HBV re-infection, even in HBV replicative cirrhotic, patients. The optimal HBIG protocol in the LAM era is yet to be defined: dosing of HBIG, routes of administration, and possibility of stopping HBIG. Several antiviral drugs have been developed for the management of HBV infection on the graft, so outcome is currently good. 相似文献
49.
血清乙型肝炎病毒标志物不同表现模式及肝功能异常对肾移植受者存活率的影响 总被引:1,自引:0,他引:1
目的 探讨血清乙型肝炎病毒标志物不同表现模式对肾移植受者长期存活的影响。方法 对 62例血清乙型肝炎病毒标志物阳性者及 1 96例血清乙型肝炎病毒标志物全阴性者肾移植术后的肝功能、人肾均存活的存活率等指标进行随访和回顾性分析。结果 术后早期血清乙型肝炎病毒标志物阳性组与血清乙型肝炎病毒标志物阴性组比较 ,肝功能异常发生率的差异无显著性 (P >0 .0 5) ;术后中远期 ,HBsAg、HBeAg及抗 HBc阳性者的肝功能受损率明显高于血清乙型肝炎病毒标志物阴性组及HBsAg、抗 HBe、抗 HBc阳性者 (P <0 .0 5) ,其人肾均存活的存活率也最低 (P <0 .0 5)。结论 对HBsAg、抗 HBe及抗 HBc阳性者进行肾移植应慎重 ,而HBsAg、HBeAg及抗 HBc阳性者则不适宜接受肾移植 相似文献
50.
Fumonisins as a possible contributory risk factor for primary liver cancer: A 3-year study of corn harvested in Haimen, China, by HPLC and ELISA 总被引:13,自引:0,他引:13
Y. Ueno K. Iijima S.-D. Wang Y. Sugiura M. Sekijima T. Tanaka C. Chen S.-Z. Yu 《Food and chemical toxicology》1997,35(12):1143-1150
Employing HPLC fluorometry, gas-liquid chromatography (GLC) and a novel enzymelinked immunosorbent assay (ELISA) based on a monoclonal antibody, 40 corn samples, each collected in 1993 from agricultural stocks for human consumption in Haimen (Jiangsu County) and Penlai (Shandong Province), high- and low-risk areas for primary liver cancer (PLC) in China, respectively, were analysed for fumonisins (FBs), aflatoxins (AFs) and trichothecenes. Levels and positive rates of FBs and deoxynivalenol (DON) were significantly higher in Haimen than in Penlai. ELISA of the 40 corn samples harvested in the two areas in 1994 revealed that FB contamination levels and rates in these areas were comparable to those observed in 1993 in Haimen. ELISA analysis of 1993 and 1994 products revealed a wide occurrence of AFB1 but the positive rates as well as levels were not significantly different between these areas. ELISA of the same sample number of corn harvested in 1995 revealed that FB contamination in Haimen was significantly higher than in Penlai. These 3-yearly surveys of corn samples (240 in total) demonstrated that corn harvested in Haimen was highly contaminated with FBs and that the contamination level, as well as positive rate in 1993 and 1995, were 10–50-fold higher than those in Penlai, suggesting FBs as a risk factor for promotion of PLC in endemic areas, along with the trichothecene DON. Co-contamination with AFs, potent hepatocarcinogens, was assumed to play an important role in the initiation of hepatocarcinogenesis. 相似文献