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排序方式: 共有460条查询结果,搜索用时 62 毫秒
71.
72.
目的:优化大孔吸附树脂回收制川乌炮制有毒废水中6种生物碱类成分的工艺条件,为其他药物炮制废水的处理提供参考。方法:以苯甲酰新乌头原碱、苯甲酰乌头原碱、苯甲酰次乌头原碱、新乌头碱、次乌头碱和乌头碱的吸附率和洗脱率为考察指标,利用静态吸附-洗脱试验对15种大孔吸附树脂进行筛选,并通过与动态吸附相结合的方法,优选大孔树脂的回收工艺参数。结果:D101型大孔树脂对制川乌炮制废水中6种生物碱类成分具有较好的吸附和洗脱效果,最佳工艺参数为每克大孔树脂可处理4. 3 g川乌的炮制废水,上样速度≤3. 0 m L·min-1为宜,水洗除杂用量2 BV,加70%乙醇6 BV洗脱。苯甲酰新乌头原碱、苯甲酰乌头原碱、苯甲酰次乌头原碱新、新乌头碱、次乌头碱、乌头碱的回收率依次为98. 03%,94. 09%,96. 53%,78. 15%,85. 40%,70. 57%。结论:D101型大孔树脂在进行制川乌炮制废水减毒处理的同时,还可对其所含的6种生物碱类成分进行有效回收,在解决环保问题的同时,创造了一定的经济效益,且优选的工艺条件稳定可行。 相似文献
73.
Intracellular trafficking of somatostatin receptors 总被引:1,自引:0,他引:1
The somatostatin receptor subtypes 1-5 (sst(1)-sst(5)) exhibit different intracellular trafficking and endosomal sorting after agonist exposure. The internalization of the somatostatin receptor subtypes sst(2), sst(3) and sst(5) occurs to a much higher extent after somatostatin exposure than of sst(1) or sst(4). After endocytosis, sst(2) and sst(5) recycle to the plasma membrane, whereas sst(3) is predominantly down-regulated. This review will focus on the molecular mechanisms of the differential intracellular trafficking of sst(2), sst(3) and sst(5), and discusses our current knowledge on somatostatin receptor interacting proteins. 相似文献
74.
Barbara Hausott Alexandra Förste Fabian Zach Stefan Mangger Ellen Margrethe Haugsten Lars Klimaschewski 《Anatomical record (Hoboken, N.J. : 2007)》2019,302(8):1268-1275
In the course of peripheral nerve regeneration, axons encounter different extracellular growth factors secreted by non-neuronal cells at the injury site and retrogradely transported after binding to neuronal membrane receptor tyrosine kinases. The present study reviews the role of receptor transport in peripheral axon outgrowth and provides novel data on trafficking of fibroblast growth factor receptor type 1 (FGFR1). Differences in receptor transport are determined by different numbers of lysine residues acting as ubiquitination sites in the intracellular receptor domain. We previously demonstrated that overexpression of mutant FGFR1-25R (25 out of 29 intracellular lysines replaced with arginine) results in enhanced receptor recycling as compared to wild-type FGFR1 followed by strong stimulation of elongative axon growth in vitro. Here, the effects of lysine-deficient FGFR1 (FGFR1-29R lacking all 29 cytoplasmic lysine residues) or of only 15 lysine mutations (FGFR1-15R) on axon outgrowth and concomitant changes in signal pathway activation were investigated by immunocytochemistry and morphometry of cultured primary neurons. Overexpression of FGFR1-15R in adult sensory neurons resulted in enhanced receptor recycling, which was accompanied by increased axon elongation without stimulating axon branching. By contrast, FGFR1-29R was neither endocytosed nor axon outgrowth affected. Although overexpression of FGFR1-15R or FGFR1-25Ra strongly promoted elongation, we did not detect increased signal pathway activation (ERK, AKT, PLC, or STAT3) in neurons expressing mutant FGFR1 as compared with wild-type neurons raising the possibility that other signaling pathways or signaling independent mechanisms may be involved in the axon outgrowth effects of recycled FGF receptors. Anat Rec, 302:1268–1275, 2019. © 2019 The Authors. The Anatomical Record published by Wiley Periodicals, Inc. on behalf of American Association of Anatomists. 相似文献
75.
Kirill Petropavlovskii Tatiana Novichenkova Victoria Petropavlovskaya Mikhail Sulman Roman Fediuk Mugahed Amran 《Materials》2021,14(21)
Increasing the efficiency of using gypsum binders can be carried out by using not natural gypsum raw materials, but calcium sulfate-containing waste from various industries (phosphogypsum, borogypsum, citrogypsum, etc.). As the main source material in the work, we used gypsum-containing waste from a faience factory in the form of waste molds for casting dishes, souvenirs and plumbing fixtures. It has been established that the optimal binding system is formed by mixing powders of dihydrate technogenic gypsum from a coarse and fine earthenware factory with average particle diameters of 3.473 microns and 3.065 microns in a percentage ratio of 30:70, respectively. Using a computer software developed by the authors, which makes it possible to simulate the microstructure of a raw mixture taking into account the contact interaction of particles and calculate the average coordination number, models of binary packing of particles were constructed at various ratios of their diameters. Studies of the strength of composites obtained on the basis of bidisperse systems have shown the presence of an extremum in the region of mixtures containing 30% coarse powder. With optimal packing, a large number of phase contacts are formed due to the regulation of the grain composition of the bidisperse system. It was revealed that a brick based on the waste of two-water gypsum from earthenware production has 2.5–5 times better characteristics of compressive strength than traditional building wall products based on natural gypsum. At the same time, the strength immediately after molding is more than 3 times higher than that of traditional gypsum products. Even higher indicators are achieved when adding microcalcite in addition to the waste of earthenware production, in this case, the compressive strength is 3–6 times higher, and the strength immediately after molding is almost 3 times higher than that of traditional gypsum products. 相似文献
76.
Alan H. Wadsworth John J. Newman Mark D. Wipperman Ian Fellows Derek R. Sutherland 《Journal of labelled compounds & radiopharmaceuticals》2000,43(1):11-28
Versions of adenosine receptor agonist GR79236 (1 ), labelled either with carbon-14 (9 ) at C-8 of the purine ring or with tritium (15 ) in the cyclopentyl ring, were prepared in overall yields of 64% and 25% respectively. A mass labelled [M+4] version (24 ) containing carbon-13, nitrogen-15, and deuterium was also prepared in 3% yield. Copyright © 2000 John Wiley & Sons, Ltd. 相似文献
77.
Stanisaw Maecki Krzysztof Gargul Marek Warzecha Grzegorz Stradomski Artur Hutny Mateusz Madej Micha Dobrzyski Ryszard Prajsnar Grzegorz Krawiec 《Materials》2021,14(20)
A highly effective method of the processing of steelmaking dust in an arc-resistant furnace has been presented. The aim of the research was to investigate the possibility of processing steelmaking dust in terms of waste minimization and selective recovery of valuable components. For this purpose, an electric arc resistance furnace was used. Granulated steelmaking dust with reducer (coal dust) was the input material. The products of the process are zinc oxide, iron alloy and slag, with properties meeting high ecological requirements. The technology does not generate solid waste. Zinc recovery is over 99% and iron recovery over 98%. The content of heavy metals (Zn + Pb + Cu) in glassy slag is below 0.2%, which ensures very low leachability. 相似文献
78.
The subjects of this study were mortars with varying amounts of recycled ceramic aggregate (RCA). As part of the fine aggregate, the RCA volume share is 10%, 20%, 30%, 50% and 100%. First, fresh mixture parameters were evaluated, such as consistency and air content measurement by pressure method. Next, specimens were molded for compressive strength and flexural strength tests after 7, 28 and 56 days of curing. The thermo-humidity parameters of the composites, i.e., coefficient of capillary action and thermal conductivity coefficient were also investigated using nonstationary method. Sorption kinetics of the mortars at different moisture conditions at 20 °C were also evaluated. Sorption tests were carried out using two methods: TM and DVS. The sorption isotherms were plotted on the basis of equilibrium moisture content for the materials tested. The isotherms obtained by the two methods were evaluated. The results allowed us to draw conclusions on the physical and mechanical parameters of the composites with different amounts of RCA and to evaluate the ability to absorb moisture from the environment by these types of materials. A clear decrease in the compressive strength after 28 days of curing compared to the reference mortar was recorded after using 30% to 100% of RCA (approx. 26% to approx. 39%). Changes in flexural strength were significantly smaller, reaching no more than approx. 7.5%. It was shown that the amount of RCA translates into the ability to sorb moisture, which may affect the application of this type of composites. The amount of RCA translates also into the thermal conductivity coefficient, which decreased with increasing amount of RCA. 相似文献
79.
Alternative binders activated by forced carbonisation are regarded as one of the potential solutions to reducing greenhouse gas emissions, water, and energy consumption. Such binders, in particular those based on nepheline sludge (a by-product of alumina production), cured in carbon dioxide with subsequent hydration, are clinkerless building materials. The development of such binders contributes to the involvement of multi-tonnage solid industrial waste in the production cycle. This type of waste is capable of binding man-made CO2 and transforming it into stable insoluble compounds, having binder properties. The optimum technological parameters of the forced carbonisation of the nepheline slime binder was determined by the mathematical planning of the experiment. The novelty of the research is the expansion of the secondary raw material base that can bind the man-made CO2 with obtaining the construction products of appropriate quality. It was revealed that the process of active CO2 absorption by the minerals of nepheline slime is observed in the first 120 min of the forced carbonization. Immediately after carbonisation, the resulting material develops compressive strength up to 57.64 MPa, and at the subsequent hydration within 28 days this figure increases to 68.71 MPa. Calcium carbonate is the main binder that determines the high mechanical properties of the samples. During the subsequent hydration of the uncoated belite, gel-like products are formed, which additionally harden the carbonised matrix. Thus, after the forced carbonisation and the following 28 days of hardening, the material with compressive strength in the range 4.38–68.71 MPa and flexural strength of 3.1–8.9 MPa was obtained. This material was characterised by water absorption by mass in the range of 13.9–23.3% and the average density of 1640–1886 kg/m3. The softening coefficient of the material was 0.51–0.99. The results obtained enables one to consider further prospects for research in this area, in terms of the introduction of additional technological parameters to study the process of forced carbonisation of nepheline slime. 相似文献
80.