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11.
The above article, published online on 4 March 2013 in Wiley Online Library ( wileyonlinelibrary.com ), has been retracted by agreement between the authors, the journal Editor in Chief, Tony Wilson, the Royal Microscopical Society and John Wiley & Sons Ltd. The retraction has been agreed following an investigation by an ad hoc advisory committee of senior faculty members assembled by the College of Engineering, Carnegie Mellon University. The committee concluded that all the parties involved acted honourably, but implicit misunderstandings and unintended miscommunications led to the unfortunate inclusion of several images used in the study without proper approval from the copyright owner. 相似文献
12.
IP Aspin I Hamerton BJ Howlin JR Jones MJ Parker 《Surface Coatings International Part B: Coatings Transactions》1998,81(2):68-71
Conclusions The combined techniques of radiolabelling and computer simulation provide a powerful way of monitoring the actual mechanisms and reactivity of epoxy cure. The information obtained from this treatment allows the understanding of the structure:activity relationships in epoxy cure reactions and permits the design of curing agents with improved or decreased reactivity. A decreased reactivity would be useful for improving the shelf-life of the resin. A decreased k2 would lead to materials with good tack and drape properties. The potential for controllable B-staging is also evident in such a system with a reduced k2. 相似文献
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M Marinaro PN Boyaka RJ Jackson FD Finkelman H Kiyono E Jirillo JR McGhee 《Canadian Metallurgical Quarterly》1999,162(1):114-121
We have investigated the effects of IL-12 and cholera toxin (CT) on the immune response to tetanus toxoid (TT) given by intranasal or oral routes. CT inhibited IL-12-induced IFN-gamma secretion both in vivo and in vitro. Intranasal administration of IL-12 to mice nasally immunized with the combined vaccine of TT and CT resulted in increased TT-specific IgG2a and IgG3 Abs, while IgG1 and IgE Ab responses were markedly reduced. This shift of the CT-induced immune response toward Th1 type was associated with TT-specific CD4+ T cells secreting IFN-gamma and reduced levels of Th2-type cytokines (i.e., IL-4, IL-5, IL-6, and IL-10). In contrast, intranasal IL-12 enhanced the CT-induced serum IgG1 and IgE Ab responses in mice given the combined vaccine orally. IFN-gamma secretion by TT-specific CD4+ T cells was also enhanced; however, Th2-type cytokine responses were predominant. Mucosal secretory IgA responses to oral or nasal vaccines were not affected by intranasal IL-12. Thus, intranasal IL-12 delivery influences Th cell subset development in mucosal inductive sites that are dependent on the route of vaccine delivery. 相似文献
15.
JR Paugh 《Canadian Metallurgical Quarterly》1992,69(10):805-810
Although many investigations have examined the parameters of hydrogel lens hydration loss, the in vivo effect (in humans) on lens oxygen behavior has not been characterized previously. Human subjects wore 2 different lenses (a thin, 38% water polymacon lens and a thin, 55% water bufilcon lens) for 5-min periods under either fully hydrated (i.e., with saline regularly applied to the lens) or partially hydrated (i.e., with "normal" wear of 1 blink every 5 s) conditions. An equivalent oxygen percentage (EOP) technique and a gravimetric method were used to determine lens oxygen behavior and hydration, respectively. The hydration results demonstrate that significant lens dehydration occurs during the partially hydrated (normal blink rate) condition compared to the in situ, fully hydrated situation. A corresponding, statistically significant diminution in oxygen equivalency was also observed. 相似文献
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K Pantel M von Knebel Doeberitz JR Izbicki G Riethmüller 《Canadian Metallurgical Quarterly》1997,68(12):1241-1250
The incidence of local relapse after complete (R0) resection of solid tumors is largely determined by the skill of the surgeon, whereas metastatic relapse in distant organs is caused by pre- or perioperative systemic dissemination of tumor cells. The presence of individual disseminated tumor cells--e.g., in bone marrow as indicator organ--can be detected by sensitive immunocytochemical and molecular methods and is increasingly considered as a clinically relevant prognostic indicator. In contrast to solid metastases, isolated micrometastatic tumor cells are appropriate targets for intravenously applied anti-cancer therapeutics because they are easily accessible to macromolecules and immunologic effector cells. The majority of these tumor cells appear to be nonproliferating (i.e., in the G0 phase of the cell cycle), which may explain the failure of adjuvant chemotherapy. Adjuvant therapeutic strategies aimed at quiescent tumor cells are therefore of increasing interest. This therapeutic rationale has been tested and confirmed in a randomized clinical trial using antibody 17-1A in patients with non-metastatic colorectal carcinoma (UICC stage III). The antibody therapy kills also quiescent tumor cells ("dormant cells") and is independent from a potential chemotherapy resistance of the tumor cells. As treatment for minimal residual cancer, the clinical use of antibody therapy could be envisaged in conjunction with chemotherapy, applied either in parallel or sequentially. The aim of this review is to present and discuss the current state of research in the field of diagnosis and therapy of minimal residual cancer. 相似文献
19.
Epithelioid smooth-muscle tumors of the uterus are uncommon neoplasms for which prognostic factors have not been well established. A retrospective follow-up study of 18 uterine epithelioid smooth-muscle tumors was performed. Patients ranged in age from 27 to 83 years (mean, 45 years) and were separated into three groups based on the nuclear grade of the epithelioid tumor cells. Two tumors had grade 1 nuclei; both were examples of intravenous leiomyomatosis. They had highest mitosis counts of 1 and 3 mitotic figures (MF)/10 high-power fields (HPF), no tumor cell necrosis was found, and both patients were alive with no evidence of disease at 64 and 5 months' follow-up. Ten tumors had grade 2 nuclei. All had highest mitosis counts of 0 to 3 MF/10 HPF, except one (5 MF/10 HPF). Tumor cell necrosis was absent in nine and only one had an infiltrative border. Tumor size ranged from 1.5 to 14 cm. Two tumors contained pleomorphic ("symplastic") multinucleated giant cells similar to those seen in bizarre leiomyomas. All nine patients with follow-up were alive with no evidence of disease 5 to 203 months postoperatively (median, 74 months). One patient had also received adjuvant radiation therapy. Six tumors had grade 3 nuclei. Highest mitosis counts of 4 to 9 MF/10 HPF were found in five; one had 1 MF/10 HPF. Maximum tumor size ranged from 4.5 to 13 cm. Two had tumor cell necrosis, and two had an infiltrative border. Two of these patients died of tumor 11 and 132 months postoperatively. The former had widespread metastases at initial surgery (stage IVb); the latter patient (stage I) developed the first of seven tumor recurrences 3 years postoperatively. Both patients had also received adjuvant chemotherapy. Of the remaining four patients, two were alive with no evidence of disease at 48 and 83 months, one was alive (tumor status unknown) at 28 months, and one was lost to follow-up. Based on our findings and those in the literature, we conclude that uterine smooth-muscle tumors with a predominance of epithelioid cells are extremely uncommon and metastasize infrequently. No single histologic feature is predictive of metastatic potential. Clinically malignant tumors (i.e., epithelioid leiomyosarcomas) typically have the combination of significant nuclear atypia (either grade 2 or grade 3 nuclei) and some mitotic activity (usually at least 3 to 4 MF/10 HPF); most also have tumor cell necrosis. 相似文献
20.
Carbohydrate-deficient-glycoprotein syndrome type 1 (CDG1; also known as "Jaeken syndrome") is an autosomal recessive disorder characterized by defective glycosylation. Most patients show a deficiency of phosphomannomutase (PMM), the enzyme that converts mannose 6-phosphate to mannose 1-phosphate in the synthesis of GDP-mannose. The disease is linked to chromosome 16p13, and mutations have recently been identified in the PMM2 gene in CDG1 patients with a PMM deficiency (CDG1A). The availability of the genomic sequences of PMM2 allowed us to screen for mutations in 56 CDG1 patients from different geographic origins. By SSCP analysis and by sequencing, we identified 23 different missense mutations and 1 single-base-pair deletion. In total, mutations were found on 99% of the disease chromosomes in CDG1A patients. The R141H substitution is present on 43 of the 112 disease alleles. However, this mutation was never observed in the homozygous state, suggesting that homozygosity for these alterations is incompatible with life. On the other hand, patients were found homozygous for the D65Y and F119L mutations, which must therefore be mild mutations. One particular genotype, R141H/D188G, which is prevalent in Belgium and the Netherlands, is associated with a severe phenotype and a high mortality. Apart from this, there is only a limited relation between the genotype and the clinical phenotype. 相似文献