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排序方式: 共有2661条查询结果,搜索用时 15 毫秒
81.
AD Foey SL Parry LM Williams M Feldmann BM Foxwell FM Brennan 《Canadian Metallurgical Quarterly》1998,160(2):920-928
IL-10 is an anti-inflammatory cytokine with potent immunomodulatory effects, including inhibition of cytokine production. However, regulation of monocyte IL-10 production is poorly understood. In this report we have investigated the mechanisms of LPS-induced IL-10 production by human peripheral blood monocytes and demonstrate that IL-10 synthesis is uniquely dependent on the endogenous proinflammatory cytokines IL-1 and/or TNF-alpha. LPS signal transduction in monocytes has been shown to involve activation of the p38 and p42 mitogen-activated protein kinase (MAPK) cascades. The results in this paper indicate that inhibition of p38 MAPK potently inhibited the production of IL-10, IL-1beta, and TNF-alpha, whereas blockade of the p42/44 MAPK pathway, while partially inhibiting TNF-alpha and IL-1beta production, had no effect on monocyte secretion of IL-10. Furthermore, neither the inhibition of monocyte TNF-alpha induced by IL-10 nor the stimulation of soluble TNF receptor production was affected by inhibition of the p42/44 MAPK pathway, suggesting that this signaling event is not involved in either monocyte production of or anti-inflammatory responses to IL-10. These data raise the interesting possibility that proinflammatory TNF-alpha-mediated effects may be selectively blocked without modulating the induction or the response to IL-10, whereas the signaling events associated with the anti-inflammatory events induced by IL-10 remain to be elucidated. 相似文献
82.
C Mao R Vig TK Venkatachalam EA Sudbeck FM Uckun 《Canadian Metallurgical Quarterly》1998,8(16):2213-2218
83.
Psychoanalysis has been in a constant uninterrupted debate about its identity as a discipline and as a social institution. This article considers the place of science in psychoanalysis, on the one hand, and the hermeneutic nature of our discipline, on the other. The aim is to articulate a typology of psychoanalytic knowledge that characterizes psychoanalysis as a form of therapy, an intellectual movement, and a theoretical system. This typology considers psychoanalysis as a thought collective that influences its members by exchanging and maintaining ideas. To be a well-rounded psychoanalytic thinker or practitioner one must be able to move easily among three realms of knowledge--the humanities, the social sciences, and the natural sciences. Each realm has its own criteria of truth and the challenge is to know when to employ which criteria. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
84.
Ambient, biological, and biological effect monitoring of exposure to polycyclic aromatic hydrocarbons (PAHs) 总被引:1,自引:0,他引:1
BA Hatjian JW Edwards J Harrison FM Williams PG Blain 《Canadian Metallurgical Quarterly》1995,77(1-3):271-279
A novel strategy was utilised to assess the risk to health from exposure to polycyclic aromatic hydrocarbons (PAHs). Ambient monitoring was carried out by personal sampling. Urinary thioethers (UTh) and urinary 1-hydroxypyrene (1-HP) were utilised for biological monitoring. Urinary d-glucaric acid (UDGA) and sister chromatid exchange (SCE) in peripheral blood lymphocytes were used as biological effect markers. The population was categorised into exposed and control groups according to the external dose of PAHs. The excretion of 1-HP in the controls over the 3-day period showed a relatively stable baseline, while the exposed showed a significant increase over the same period of time. SCE frequency in the exposed population was significantly different from controls. 相似文献
85.
FM Scott AM Treston GL Shaw I Avis J Sorenson K Kelly EC Dempsey AB Cantor M Tockman JL Mulshine 《Canadian Metallurgical Quarterly》1996,14(2-3):239-251
Monitoring respiratory epithelial biology may reveal individuals with incipient lung cancer. The expression of neuroendocrine (NE) markers in pulmonary epithelium is thought to be central to lung development, repair of injury and may contribute to carcinogenesis. In this study, we evaluate several candidate NE markers to determine the feasibility of prospective analysis of clinical specimens. The potential NE markers include the enzyme L-DOPA decarboxylase (DDC), the neuropeptide gastrin releasing peptide (GRP), and peptidyl-glycine alpha-amidating monooxygenase (PAM), the bifunctional enzyme responsible for the final bioactivation step of many neuropeptides. A comparison of PAM activity and DDC levels in 30 lung cancer cell lines indicated that peptide amidating activity may be an indicator of NE status. Bronchoalveolar lavage (BAL) fluid from subjects at risk of developing second primary lung cancer and from volunteers was obtained. The activity of the first PAM enzyme, peptidylglycine alpha-hydroxylating monooxygenase (PHM), ranged from not detectable to 507 pmol/h/mg protein in 57 specimens. The second PAM enzyme, peptidylamidoglycolate lyase (PAL), ranged from not detectable to 414 pmol/h/mg protein in 56 specimens. Using cluster analysis by the average linkage method, a group of enzyme values with PHM greater than 230 pmol/h/mg protein was determined. Long-term follow-up of these patients for new second primary lung cancers may help to determine the potential predictive value of PAM detected in the BAL fluid. 相似文献
86.
M Monti V Pasta D Antonucci F Boccaccini FM Di Matteo S Lucci 《Canadian Metallurgical Quarterly》1996,17(10):543-546
The Authors report their experience in the treatment of ventral hernias using a Marlex mesh moulded in an original way with a technique partially derived from plastic surgery. The complete mobilization of the umbilicus through a circular incision allows to fit this prosthesis symmetrically below the rectus abdominis muscles for the entire extension of the hernia. 相似文献
87.
88.
N Raffaelli FM Pisani T Lorenzi M Emanuelli A Amici S Ruggieri G Magni 《Canadian Metallurgical Quarterly》1997,179(24):7718-7723
The enzyme nicotinamide mononucleotide (NMN) adenylyltransferase (EC 2.7.7.1) catalyzes the synthesis of NAD+ and nicotinic acid adenine dinucleotide. It has been purified to homogeneity from cellular extracts of the thermophilic archaeon Sulfolobus solfataricus. Through a database search, a highly significant match was found between its N-terminal sequence and a hypothetical protein coded by the thermophilic archaeon Methanococcus jannaschii MJ0541 open reading frame (GenBank accession no. U67503). The MJ0541 gene was isolated, cloned into a T7-based vector, and expressed in Escherichia coli cells, yielding a high level of thermophilic NMN adenylyltransferase activity. The expressed protein was purified to homogeneity by a single-step chromatographic procedure. Both the subunit molecular mass and the N-terminal sequence of the pure recombinant protein were as expected from the deduced amino acid sequence of the MJ0541 open reading frame-encoded protein. Molecular and kinetic properties of the enzymes from both archaea are reported and compared with those already known for the mesophilic eukaryotic NMN adenylyltransferase. 相似文献
89.
90.
Investigation on germanium oxide-based glasses for infrared optical fibre development 总被引:1,自引:0,他引:1
We demonstrate the suitability of GeO2 for fibre engineering by compositional modifications of core and cladding glasses using the rod-in-tube technique, which have been matched for fibre drawing. The methods adopted for identifying the core–clad combination (56GeO2–31PbO–9Na2O–4Ga2O3 and 55GeO2–30PbO–11Na2O–4Ga2O3) are explained, based on the thermal, viscosity, and optical properties. We specially point out to the relatively high transformation temperature range (Tg > 380 °C) of the glass, which is suitable for chemical sensing and metrological applications in the 150–200 °C. The total intrinsic loss is compared with the measured loss in multi- and single-mode fibres from 0.532 to 2.02 μm, with loss less than 2.5 dB m−1 in the 1000–1600 nm range. The origin of larger loss outside this region is explained. 相似文献