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This study investigated the contribution of psychosocial work characteristics (decision latitude, job demand, social support at work, and effort-reward imbalance) to health-related quality of life. Data were derived from 2 aircraft manufacturing plants (N = 1,855) at the start of a longitudinal study. Regression analysis showed that work characteristics (1st model) explained 19% of the variance in the mental summary score of the Short Form-12 Health Survey. R2 change for work characteristics decreased to 13%, accounting for demographics, socioeconomic status, body mass index, and medical condition (5th model). Including health behavior and personality factors (full model), R2 change for work characteristics remained significant. Psychosocial work characteristics account for relevant proportions in the subjective perception of mental health beyond a wide array of medical variables and personality factors. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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We have constructed new B domain deletion derivatives of humanfactor Vm (FVm) by manipulating the cDNA using recombinant DNAtechniques. One of these new derivatives, FVIII II, in whichamino acids 771(pro)–1666(asp) have been deleted, no longercontains the protease cleavage site at amino acid position 1648(arg)–1649(glu) known to be involved in the initial step ofFVin processing. We have expressed this molecule in both babyhamster kidney (BHK) 21 cells using the vaccinia virus (VV)expression system and have established Chinese hamster ovary(CHO) derived permanent cell lines expressing either recombinant(r)FVIII or FVIII II AD. The characteristics of FVIII II ADhave been compared to those of rFVIII and/or plasma derived(pd) FVIII. FVIII II All has the following properties: (i) itexhibits FVDI procoagulant activity; (ii) it is expressed at5-fold higher levels than is the complete molecule in comparablesystems; (iii) it migrates for the most part as a single majorband on SDS-PAGE, hi contrast to the complete molecule; (iv)it is activated to a greater extent by thrombin than is eitherrFVm or pdFVIII; and (v) it retains the ability to bind vonWillebrand factor (vWf).  相似文献   
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The ex vivo expansion and maintenance of long-term hematopoietic stem cells (LT-HSC) is crucial for stem cell-based gene therapy. A combination of stem cell factor (SCF), thrombopoietin (TPO), FLT3 ligand (FLT3) and interleukin 3 (IL3) cytokines has been commonly used in clinical settings for the expansion of CD34+ from different sources, prior to transplantation. To assess the effect of IL3 on repopulating capacity of cultured CD34+ cells, we employed the commonly used combination of STF, TPO and FILT3 with or without IL3. Expanded cells were transplanted into NSG mice, followed by secondary transplantation. Overall, this study shows that IL3 leads to lower human cell engraftment and repopulating capacity in NSG mice, suggesting a negative effect of IL3 on HSC self-renewal. We, therefore, recommend omitting IL3 from HSC-based gene therapy protocols.  相似文献   
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Chloramphenicol (CAP) is an antibiotic used for the treatment of bacterial infections in human and veterinary medicine. The use of CAP was prohibited in the European Union in 1994. Control laboratories are required to use suitably validated analytical methods to check sample compliance with the regulation. A quantitative method based on liquid chromatography coupled to isotopic dilution tandem mass spectrometry was developed for the determination of chloramphenicol in honey, shrimp, and poultry meat. The experimental protocol consisted of a liquid–liquid extraction with ethyl acetate. Separation and detection were realized, respectively, by a 2690 Waters HPLC (Milford, MA, USA) and a Micromass Triple Quadrupole mass spectrometer (Micromass, Manchester, UK), equipped with an electrospray source. The effects of mobile-phase additives on the response of LC/ESI/MS were examined. Two different HPLC columns were tested: the X-Terra from Waters and the Alltima HP C18 HL from Alltech (Deerfield, IL, USA). A validation of the method was conducted according to the EU criteria for the analysis of chloramphenicol in foods. The decision limits (CCα) were 0.04, 0.03, 0.07 μg?kg?1, and the detection capabilities (CCβ) were 0.05, 0.04, 0.08 μg?kg?1 for honey, shrimp, and poultry meat, respectively. Those values are below the minimum required performance limit set at 0.3 μg?kg?1 by the EU and 0.1 μg?kg?1 by Belgium. Our protocol has the advantage to propose a unique extraction method working as well for honey, shrimp, and poultry meat, contrary to similar published methods in which a different extraction method is used for each type of matrix.  相似文献   
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G protein-coupled receptor 55 (GPR55) probably plays a role in innate immunity and tumor immunosurveillance through its effect on immune cells, such as T cells and NK cells. In this study, the prognostic value of GPR55 in colon cancer (CC) was investigated. mRNA expression levels of GPR55 were determined in 382 regional lymph nodes of 121 CC patients with 12 years observation time after curative surgery. The same clinical material had previously been analyzed for expression levels of CEA, CXCL16, CXCL17, GPR35 V2/3 and LGR5 mRNAs. Clinical cutoffs of 0.1365 copies/18S rRNA unit for GPR55 and 0.1481 for the GPR55/CEA ratio were applied to differentiate between the high- and low-GPR55 expression groups. Kaplan–Meier survival analysis and Cox regression risk analysis were used to determine prognostic value. Improved discrimination between the two groups was achieved by combining GPR55 with CEA, CXCL16 or CXCL17 compared with GPR55 alone. The best result was obtained using the GPR55/CEA ratio, with an increased mean survival time of 14 and 33 months at 5 and 12 years observation time, respectively (p = 0.0003 and p = 0.003) for the high-GPR55/CEA group. The explanation for the observed improvement is most likely that GPR55 is a marker for T cells and B cells in lymph nodes, whereas CEA, CXCL16 and CXCL17, are markers for tumor cells of epithelial origin.  相似文献   
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Mould growth on kiln-dried and air-dried timber   总被引:2,自引:0,他引:2  
The problem with discoloration, due to fungal growth, of wooden outdoor constructions seems to have increased in recent years. One reason for this increase might be an impact of new drying methods of timber. Modern kiln drying methods use high temperatures in an effort to shorten the drying process, which leads to fast capillary water transport and subsequently redistribution and accumulation of dissolved substances at the surface. These can then be used as nutrients by fungi. In this study, wood was dried according to different simulated drying schedules. The mould resistance of the timber was then tested. Wood dried at room temperature was used as a reference. No differences could be confirmed at the end of the test; mould growth was extensive on all the samples. However, mould growth started earlier on the kiln-dried samples than on air-dried timber. As for the discolouring fungus, there was a clear difference between wood dried at room temperature and kiln-dried wood, though no difference could be established between the two artificial methods.  相似文献   
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The use of wood is limited due to its susceptibility to wood destroying organisms. If wet for long periods, wood will be attacked by fungi and the strength properties will decrease dramatically. To overcome this disadvantage, non-durable wood can be treated with preserving chemicals. When testing durability, it is essential that wood be exposed to all kinds of wood degrading organisms that can be expected in the intended exposure environment. The aim of this study was to evaluate the relevance of exposing test ttakes in terrestrial microcosms (TMC) as an alternative to existing test procedures to judge the durability of treated and untreated wood. Small stakes of treated and untreated pine (Pinus sylvestris) sapwood were exposed in TMCs with different soils. Stakes were also exposed to pure cultures of brown and white rot fungi. After exposure, mass losses were determined and stakes from the TMCs were analysed using light microscopy to determine the types of microbial attack. The effect of the preservatives varied depending on the exposure environment. It is concluded that testing the durability of untreated and treated wood with pure cultures of fungi is too limited a test to evaluate total effectiveness. Testing in TMCs represents a good complement to existing procedures and, after further development, an alternative to other laboratory and field tests.
Résumé La vulnérabilité du bois aux micro-organismes est un facteur qui limite son usage. Lorsqu'il est mouillé pendant une période prolongée, le bois sera attaqué par des champignons, ce qui diminuera dramatiquement sa résistance. Pour pallier à ce désavantage, on peut traiter les bois les moins résistants avec des produits de préservation. Afin d'évaluer sa durabilité après traitement, il est alors essentiel d'exposer le bois à tous les types d'organismes destructeurs pouvant se trouver dans le milieu où il sera utilisé. Le but de cette étude est d'évaluer l'exposition des piquets de bois dans des microcosmes terrestres, en tant qu'essai alternatif aux procédures existantes pour évaluer la résistance des bois traités et non traités. Des petits piquets de pin sylvestre, Pinus sylvestris, traités et non traités, ont été exposés à des microcosmes terrestres, utilisant des sols différents. Les piquets ont également été exposés à des cultures pures de champignons de carie blanche et de carie brune. Après l'essai, les pertes de masse ont été déterminées et les piquets ont été analysés au microscope photonique afin d'identifier le type d'attaque microbienne subie. L'effet des produits de préservation a varié selon le milieu auquel les bois traités ont été exposés. On a conclu que des essais de durabilité effectués sur des bois traités et non traités, uniquement en présence de cultures pures de champignons, sont trop limités pour prédire l'efficacité totale d'un produit de préservation. Les essais effectués dans des microcosmes terrestres peuvent être un bon complément aux procédures existantes. Ils peuvent même devenir, après des recherches supplémentaires, une alternative à d'autres essais sur le terrain et en laboratoire.
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