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11.
Possible enhancements of DNA damage with light of different wavelengths and ionizing radiation (Rhenium-188—a high energy beta emitter (Re-188)) on plasmid DNA and FaDu cells via psoralen were investigated. The biophysical experimental setup could also be used to investigate additional DNA damage due to photodynamic effects, resulting from Cherenkov light. Conformational changes of plasmid DNA due to DNA damage were detected and quantified by gel electrophoresis and fluorescent staining. The clonogene survival of the FaDu cells was analyzed with colony formation assays. Dimethyl sulfoxide was chosen as a chemical modulator, and Re-188 was used to evaluate the radiotoxicity and light (UVC: λ = 254 nm and UVA: λ = 366 nm) to determine the phototoxicity. Psoralen did not show chemotoxic effects on the plasmid DNA or FaDu cells. After additional treatment with light (only 366 nm—not seen with 254 nm), a concentration-dependent increase in single strand breaks (SSBs) was visible, resulting in a decrease in the survival fraction due to the photochemical activation of psoralen. Whilst UVC light was phototoxic, UVA light did not conclude in DNA strand breaks. Re-188 showed typical radiotoxic effects with SSBs, double strand breaks, and an overall reduced cell survival for both the plasmid DNA and FaDu cells. While psoralen and UVA light showed an increased toxicity on plasmid DNA and human cancer cells, Re-188, in combination with psoralen, did not provoke additional DNA damage via Cherenkov light.  相似文献   
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13.
Udder defence mechanisms are not completely explained by current mastitis research. The anatomical construction of the udder implies that infection of one udder quarter does not influence the immune status of neighbouring quarters. To test this hypothesis, we compared the immune reactions of individual udder quarters in response to microbial attacks. In the course of immune reactions, polymorphonuclear leucocytes (PMN) release oxygen radicals, which can be determined by chemiluminescence (CL). Milk from 140 udder quarters of 36 cows was analysed for somatic cell count (SCC), differential cell count, viability and CL activity. Quarters with an SCC < 100,000 cells/ml and free of pathogens were defined as uninfected, all other quarters were categorized as infected. Three groups of cows were classified cytologically: group A (healthy, 11 animals, SCC limit < 100,000 cells/ml); group B (moderate mastitis, 8 cows, SCC > or = 100,000 and < 400,000 cells/ml in at least one quarter); and group C (severe mastitis, 17 cows, SCC > or = 400,000 cells/ml in at least one quarter). Infected and uninfected quarters in groups B and C were analysed separately. Viability of PMN leucocytes was significantly (P=0.0012) lower in group A (72.6%) than in healthy quarters of group C (84.0%). Lowering the SCC limit of healthy quarters to <50,000 cells/ml (group A: all quarters within the udder) revealed striking differences between samples of groups B and C: in addition to varying differential cell counts and viabilities, CL activity of group B<50 (2929 CL units/million PMN) was markedly lower than that of the other groups (5616 in group A<50 and 6445 CL units/million PMN in group C<50). These results allow the conclusion that the infection of one udder quarter influences the cell activity of neighbouring quarters. When the SCC threshold for healthy quarters was reduced to 50,000 cells/ml, greater differences in cell activities were detected between healthy udders and healthy quarters of infected udders.  相似文献   
14.
Visualizing and simulating formal models in a flexible way becomes increasingly important for the design of complex systems. With GenGED, a tool is available which automatically generates a visual environment to process (create, edit, check, simulate) visual models over a specified visual language. Both the specification of the language and the model manipulation are based on graph grammars. In this paper, we present the means to transform visual models into application oriented views, called scenario views. We show how a model is consistently transferred to a scenario views and animated there. The extension of GenGED concerning scenario animation is discussed.  相似文献   
15.
Summary Replicas from radially and tangentially cut and split sapwood sample sof Plathymeinia foliolosa and Plathymenia reticulata were investigated by electron microscopy. The electron micrographs were compared with the aspects of sections and veplicas as seen with the light microscope, using bright field and phase contrast. It was possible to demonstrate the structure of the vascular vestured pits as represented in fig. 10 and to obtain datails on the fine structure of the different parts of the pit cavily. The bordered pits in the vessels are vestured both at the outer and inner apertures. The appearance of the vestured apertures is due to processes which are attached to the borders of the apertures. They vary according to number, size, and form and can be characteried there by main structural types: simple (papilloid), coralloid, and distincltly brauched. The electron microscope reverals no fine structure of the processes; they appear to be amor phous. The pit canal crosses the secondary wall mostly without alterations in diameter. The wall appears to be smooth and no processes were observed. On the pit chamber coated by the tertiary wasl smaller processes may occur, surrounding the verstured aperture. To the periphery, wartliary wall of the vessels. The corerlation between the amorphous wart structure and the processes was emphasied and the proballe analogy of the two structures, both covecring the tertiary wal, was discussed. The pit membrane consists of the primary walls of the adjacent cells with the middle lamella in between. The loosely interworen microfibrils, typical for the primary wall, were clearly visible. Oecacionally, “blind” pits were found, meaning that these pils had no complement on the adjacent cell elemnt. In these cases, the pit membrane was corerred by the secomdary wall thereby closring the pit chamber completely. In the half-bordered pit pairs of the paratracheal and ray parenchyma, only the bordered pits of the trachery elemnts were found to be vestured. Vestured pits in the cessels are characteristic for the two species of Plathymenia and may be considered as jeature of the geuns. Distinuctice for the species are the coalescent, slitlike aperfares in Pathymema joliolosa as well as the prevailing of the simplet papilloid) and coralloid strunctures of the processes in Plathymenia retiulata

Die Untersuchungen wurden mit Unterstützung des Conselho Nacional de Pesquisas (Brasilianischer Forschungrat) durchgeführt.  相似文献   
16.
Biogas‐storage‐ and Biogas‐filling‐facilities – Approvals for construction products and techniques In accordance with the building and water regulations, assessments of fitness for use pursuant to the Building Codes can be issued for construction products and techniques used in storage and filling facilities of biogas plants since September 2015. The article explains which building and water regulations apply to construction products and techniques intended for such use. The requirements in both legislative areas have considerable effects on the characteristics of construction products and techniques intended for contact with fermentation substrates and fermentation residues. In particular, the water regulations set out strict requirements for construction products intended for use in such facilities, which are reflected in high verification requirements for functional reliability and fitness for use. The paper focuses on general aspects, which apply to all approval elaboration and granting processes for construction products and techniques used in the before‐mentioned areas of biogas plants. More specific aspects of approval elaboration will also be addressed, using the example of selected construction products and techniques. The article provides guidance for product manufacturers and for qualified planning and design. It also explains certain specific provisions to be met by specialised firms and qualified professionals within the meaning of water legislation and by operators of biogas storage and filling facilities.  相似文献   
17.
Inherited ichthyoses represent a large heterogeneous group of skin disorders characterised by impaired epidermal barrier function and disturbed cornification. Current knowledge about disease mechanisms has been uncovered mainly through the use of mouse models or human skin organotypic models. However, most mouse lines suffer from severe epidermal barrier defects causing neonatal death and human keratinocytes have very limited proliferation ability in vitro. Therefore, the development of disease models based on patient derived human induced pluripotent stem cells (hiPSCs) is highly relevant. For this purpose, we have generated hiPSCs from patients with congenital ichthyosis, either non-syndromic autosomal recessive congenital ichthyosis (ARCI) or the ichthyosis syndrome trichothiodystrophy (TTD). hiPSCs were successfully differentiated into basal keratinocyte-like cells (hiPSC-bKs), with high expression of epidermal keratins. In the presence of higher calcium concentrations, terminal differentiation of hiPSC-bKs was induced and markers KRT1 and IVL expressed. TTD1 hiPSC-bKs showed reduced expression of FLG, SPRR2B and lipoxygenase genes. ARCI hiPSC-bKs showed more severe defects, with downregulation of several cornification genes. The application of hiPSC technology to TTD1 and ARCI demonstrates the successful generation of in vitro models mimicking the disease phenotypes, proving a valuable system both for further molecular investigations and drug development for ichthyosis patients.  相似文献   
18.
Nidogens/entactins are a family of highly conserved, sulfated glycoproteins. Biochemical studies have implicated them as having a major structural role in the basement membrane. However despite being ubiquitous components of this specialized extracellular matrix and having a wide spectrum of binding partners, genetic analysis has shown that they are not required for the overall architecture of the basement membrane. Rather in development they play an important role in its stabilization especially in tissues undergoing rapid growth or turnover. Nidogen breakdown has been implicated as a key event in the basement membrane degradation occurring in mammary gland involution. A number of studies, most compellingly those in C. elegans, demonstrated that nidogens may have other nonstructural roles and be involved in axonal pathfinding and synaptic transmission.  相似文献   
19.
Buhrke T  Merkel R  Lengler I  Lampen A 《Lipids》2012,47(4):435-442
Furan fatty acids (furan-FA) can be formed by auto-oxidation of conjugated linoleic acids (CLA) and may therefore be ingested when CLA-containing foodstuff is consumed. Due to the presence of a furan ring structure, furan-FA may have toxic properties, however, these substances are toxicologically not well characterized so far. Here we show that 9,11-furan-FA, the oxidation product of the major CLA isomer cis-9,trans-11-CLA (c9,t11-CLA), is not toxic to human intestinal Caco-2 cells up to a level of 100 μM. Oil-Red-O staining indicated that 9,11-furan-FA as well as c9,t11-CLA and linoleic acid are taken up by the cells and stored in the form of triglycerides in lipid droplets. Chemical analysis of total cellular lipids revealed that 9,11-furan-FA is partially elongated probably by the enzymatic activity of cellular fatty acid elongases whereas c9,t11-CLA is partially converted to other isomers such as c9,c11-CLA or t9,t11-CLA. In the case of 9,11-furan-FA, there is no indication for any modification or activation of the furan ring system. From these results, we conclude that 9,11-furan-FA has no properties of toxicological relevance at least for Caco-2 cells which serve as a model for enterocytes of the human small intestine.  相似文献   
20.
In order to investigate the catalytic properties, V2,38Nb10,7O32,7, VNb9O25 and solid solutions of V2O5 in TT-Nb2O5 were prepared by thermal decomposition of freeze-dried oxalate precursors. The samples were characterised by X-ray diffraction and surface area determination. The crystalline samples are capable of the intercalation of sodium and lithium ions from solution. Above a temperature of about 500 °C, in dependence on the oxygen partial pressure a reversible release and uptake of oxygen without a structural variation takes place. The catalytic properties have been evaluated for the oxidative dehydrogenation (ODH) of propane and propene. There are only small differences in the catalytic activity of the different crystalline samples. Because of the relative high starting temperature, a selective catalytic oxidation of propane to propene is hardly observed.  相似文献   
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