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排序方式: 共有497条查询结果,搜索用时 15 毫秒
111.
Kazuko Katsuki Hidenori Suzuki Masatoshi Hasegawa Michiko Heike Noriko Hosomachi Yuya Yamashita Yuta Nakamura 《Journal of Porous Materials》2007,14(4):443-448
The effects of reaction period, temperature, and iron species on the zeolite framework type were studied in this work. Gismondine
(GIS) is usually synthesized by hydrothermal method at 80°C from sodium metasilicate and aluminum nitrate as starting materials
preferentially independent of the presence/absence of iron source. However, the present work revealed that pure analcime (ANA)
could be formed at temperatures more than 120°C. A large polyhedral ANA crystal with a diameter of 180 μm was obtained even
at a comparatively low temperature such as 150°C at a short reaction period of 1 week. The presence of iron source promoted
the formation of pure ANA. Infrared spectroscopy, X-ray diffraction, and ICP-OES analysis suggested that the iron component
added as a reactant was incorporated into the ANA framework through the isomorphous substitution for Al. 相似文献
112.
Heike Schlodder Rainer Thieme Cornelius Weiss Gerhard W. Fischer Thomas Zimmermann 《Advanced Synthesis \u0026amp; Catalysis》1984,326(6):955-961
Pyrylium Compounds. XXV. Quantum Chemical Calculations Concerning the Valence Isomerization of 2-Amino-2H-pyran and -thiopyran The equilibrium 2-amino-2H-pyran 6 ⇌ 5-amino-2,4-dien-1-one 7 was investigated using the semi-empirical MINDO/3 and MNDO methods. In accordance with experimental findings for the substituted derivatives 1/2a–d , the introduction of a methyl group into the position 3 of 6 or the exchange of oxygen by sulfur shifts the equilibrium towards the cyclic structures 8 and 10 , respectively. Polar solvents, the influence of which was estimated applying the reaction field approach as well as the solvaton theory, and entropy effects are calculated to favour the ring-open valence isomer 7 . These results also correspond to experimental results. 相似文献
113.
E96V Mutation in the Kdelr3 Gene Is Associated with Type 2 Diabetes Susceptibility in Obese NZO Mice
Delsi Altenhofen Jenny Minh-An Khuong Tanja Kuhn Sandra Lebek Sarah Grigk Katharina Kaiser Christian Binsch Kerstin Griess Birgit Knebel Bengt-Frederik Belgardt Sandra Cames Samaneh Eickelschulte Torben Stermann Axel Rasche Ralf Herwig Jürgen Weiss Heike Vogel Annette Schürmann Alexandra Chadt Hadi Al-Hasani 《International journal of molecular sciences》2023,24(1)
Type 2 diabetes (T2D) represents a multifactorial metabolic disease with a strong genetic predisposition. Despite elaborate efforts in identifying the genetic variants determining individual susceptibility towards T2D, the majority of genetic factors driving disease development remain poorly understood. With the aim to identify novel T2D risk genes we previously generated an N2 outcross population using the two inbred mouse strains New Zealand obese (NZO) and C3HeB/FeJ (C3H). A linkage study performed in this population led to the identification of the novel T2D-associated quantitative trait locus (QTL) Nbg15 (NZO blood glucose on chromosome 15, Logarithm of odds (LOD) 6.6). In this study we used a combined approach of positional cloning, gene expression analyses and in silico predictions of DNA polymorphism on gene/protein function to dissect the genetic variants linking Nbg15 to the development of T2D. Moreover, we have generated congenic strains that associated the distal sublocus of Nbg15 to mechanisms altering pancreatic beta cell function. In this sublocus, Cbx6, Fam135b and Kdelr3 were nominated as potential causative genes associated with the Nbg15 driven effects. Moreover, a putative mutation in the Kdelr3 gene from NZO was identified, negatively influencing adaptive responses associated with pancreatic beta cell death and induction of endoplasmic reticulum stress. Importantly, knockdown of Kdelr3 in cultured Min6 beta cells altered insulin granules maturation and pro-insulin levels, pointing towards a crucial role of this gene in islets function and T2D susceptibility. 相似文献
114.
Oxygen activities in Fe-O-Cr melts, equilibrated with chromium oxide, were determined as a function of chromium content by EMF measurements using ZrO2(CaO) plug-type sensors with a Cr-Cr2O3 reference. Plug-type sensors with or without Cr2O3 saturator were used in the experiments. From the experimental results values for the activity coefficient fO and the interaction parameters and were evaluated. Raoultian chromium activity features a slight positive deviation from ideal solution behaviour in the temperature range from 1550 to 1650°C. Taking into account the calculated interaction parameters, the equilibrium constant KCr-O was redetermined at 1550 to 1650°C. In comparison with previous studies a better agreement was obtained with existing thermochemical data. 相似文献
115.
H Fukumoto M Nishio K Nishio Y Heike H Arioka H Kurokawa T Ishida K Fukuoka T Nomoto Y Ohe N Saijo 《Canadian Metallurgical Quarterly》1997,88(5):501-505
The operative mortality and morbidity in patients with severe left ventricular dysfunction who undergo coronary artery bypass grafting (CABG) remain high. The low ejection fraction is the major risk factor for operative mortality. However, ejection fraction (EF) alone may not necessarily be an accurate predictor of operative mortality. We studied the correlation between indices of left ventricular volume and operative mortality. One thousand patients undergoing isolated coronary bypass operations were divided into three groups according to their preoperative ejection fraction. Fifty patients (group I) had severe left ventricular dysfunction (EF < or = 0.3), 56 patients (group II) had moderately left ventricular dysfunction (0.3 < EF < or = 0.4) and 894 patients (group III) had good left ventricular function (EF > 0.4). We analyzed the relationship between hospital mortality and left ventricular volume in 106 patients with an EF < or = 0.4. RESULTS: Cardiac index was not significantly different among the three groups. The left ventricular end-diastolic pressure (LVEDP) and mean pulmonary artery pressure in groups I an II were higher than those in group III. The left ventricular end-diastolic volume (LVEDV) was 146 +/- 44 ml/m2 in Group I, 112 +/- 31 ml/m2 in Group II and 82 + 30 ml/m2 in Group III, respectively (Group I versus II, p < 0.05, Group I and II versus III, p < 0.01). The left ventricular end-systolic volume (LVESV) was 111 +/- 38 ml/m2 in Group I, 72 +/- 21 ml/m2 in Group II and 30 +/- 14 ml/m2 in Group III, respectively (Group I versus II, p < 0.05, Group I and II versus III, p < 0.01). The LVEDV and LVESV were higher in Group I than in Group II and both in Groups I and II were higher than in Group III. The hospital mortality of any cause before discharge was 8.0% (4/50) in Group I, 3.6% (2/56) in Group II, and 2.0% (18/894) in Group III. The mortality in Group I was higher than that in Group III, but the mortality between Groups I and II was not different. We assessed correlations between large left ventricle with left ventricular dysfunction and operative mortality in 106 patients with ejection fractions of < or = 0.4. The hospital mortality in patients with both under fraction 0.4 and an LVESV > or = 140 ml/m2 was 50% (4/8). This rate was higher than in patients with an LVESV between 80 and 140 ml/m2 (1.8%, 1/55) (p = 0.0006) and an LVESV less than 80 ml/m2 (2.3%, 1/43), (p = 0.0013). The hospital mortality in patients with an LVEDV > or = 200 ml/m2 was 67% (4/6). It was also higher than that in patients with an LVEDV between 200 and 120 ml/m2 (1.7%, 1/58), (p = 0.0001), and an LVEDV less than 120 ml/m2 (2.4%, 1/42), (p = 0.0004). We conclude that patients with a low ejection fraction and an elevated LVESV or LVEDV are at increased risk for hospital death following CABG. 相似文献
116.
117.
Simone Venz Heike Junker Erik Ultsch Franziska Hetke Elke Krüger Martin Burchardt Pedro Caetano-Pinto Cindy Roennau 《International journal of molecular sciences》2022,23(18)
MicroRNAs (miRNA) are ubiquitous non-coding RNAs that have a prominent role in cellular regulation. The expression of many miRNAs is often found deregulated in prostate cancer (PCa) and castration-resistant prostate cancer (CRPC). Although their expression can be associated with PCa and CRPC, their functions and regulatory activity in cancer development are poorly understood. In this study, we used different proteomics tools to analyze the activity of hsa-miR-3687-3p (miR-3687) and hsa-miR-4417-3p (miR-4417), two miRNAs upregulated in CRPC. PCa and CRPC cell lines were transfected with miR-3687 or miR-4417 to overexpress the miRNAs. Cell lysates were analyzed using 2D gel electrophoresis and proteins were subsequently identified using mass spectrometry (Maldi-MS/MS). A whole cell lysate, without 2D-gel separation, was analyzed by ESI-MS/MS. The expression of deregulated proteins found across both methods was further investigated using Western blotting. Gene ontology and cellular process network analysis determined that miR-3687 and miR-4417 are involved in diverse regulatory mechanisms that support the CRPC phenotype, including metabolism and inflammation. Moreover, both miRNAs are associated with extracellular vesicles, which point toward a secretory mechanism. The tumor protein D52 isoform 1 (TD52-IF1), which regulates neuroendocrine trans-differentiation, was found to be substantially deregulated in androgen-insensitive cells by both miR-3687 and miR-4417. These findings show that these miRNAs potentially support the CRPC by truncating the TD52-IF1 expression after the onset of androgen resistance. 相似文献
118.
Conventional drying processes like hot air-drying (HAD), freeze-drying (FD) and microwave vacuum drying (MVD) have specific advantages and disadvantages concerning product quality and drying time. Recent studies have shown that serial combinations of these processes can lead to better product quality (water content, color, hardness, rehydration, volume, and ingredient retention) and favorable process parameters (shorter time, less energy consumption). However, little is known about the timing of the changeover point between the different processes. In this study, we investigated the development of quality parameters (volume retention, rehydration properties) during FD, HAD, and MVD either as a single or as a serial combination process with varying changeover point. Therefore, carrot disks were processed in a modular drying processor to different final relative moisture contents. On this basis, recommendations were derived for certain combinations of drying processes to achieve desired product quality parameters, partially with shorter drying times. 相似文献
119.
Heike Zacharias Johannes Arndt Dr. Sophie Primig 《BHM Berg- und Hüttenm?nnische Monatshefte》2014,159(7):296-297
The case-hardening steel 18CrNiMo7???6 is used for large gear wheels in wind turbines. To achieve the requirements for a wear resistant and tough material, the steel is carburized and case hardened at 980?°C for 80 h. During this heat treatment, grain growth occurs, which should be avoided by micro-alloying the steel with aluminium and niobium. These elements pin the grain boundaries in form of carbides and nitrides to reduce the grain growth. In this work the grain size stability of several micro-alloyed variants of the case-hardening steel 18CrNiMo7???6 under different heat treatment conditions was examined. For the microstructural characterization, light microscopy, scanning, and transmission electron microscopy as well as atom probe tomography were applied. 相似文献
120.