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排序方式: 共有401条查询结果,搜索用时 31 毫秒
61.
Miyazawa M Kimura M Yabe Y Tsukamoto D Sakamoto M Horibe I Okuno Y 《Journal of oleo science》2008,57(11):585-590
The profile of volatile organic compounds (VOCs) released from Glomerella cingulata using solid phase microextraction (SPME) with different fibers, Polydimethylsiloxane (PDMS), Polydimethylsiloxane/Divinylbenzene (PDMS/DVB), Carboxen/Polydimethylsiloxane (CAR/PDMS) and Divinylbenzene/Carboxen/Polydimethylsiloxane (DVB/CAR/PDMS), was investigated. C4-C6 aliphatic alcohols were the predominant fraction of VOCs isolated by CAR/PDMS fiber. Sesquiterpene hydrocarbons represented 20.3% of VOCs isolated by PDMS fiber. During the growth phase, Ochracin was produced in the large majority of VOCs. 3-Methylbutanol and phenylethyl alcohol were found in the log phase of it. Alcohols were found in cultures of higher age, while sesquiterpenes were found to be characteristic of initial growth stage of G. cingulata. 相似文献
62.
Masayasu Ito Shuzo Murakami Masaya Okumiya Shigeru Tokita Hideharu Niwa Yoshibumi Suigihara Hideki Tanaka Takeshi Watanabe Mika Yoshinaga Katsuhiro Miura Hideharu Komoda Yuji Miyajima Tetsuji Yasutomo Sanae Namatame Hiromasa Yamaguchi 《Building Simulation》2008,1(2):178-191
The importance of LCEM (life cycle energy management) has been recognized from the view of life cycle energy savings for sustainable
buildings. The purposes of this research are the proposal of an LCEM framework and development of prototype HVAC system simulation
tools for LCEM. In this paper, the necessity of energy simulation tools for LCEM is discussed, and the outline and solution
method of the simulation tool are shown. 相似文献
63.
Kim MH Kino-Oka M Kawase M Yagi K Taya M 《Journal of Bioscience and Bioengineering》2007,104(5):428-431
We investigated the synergistic effect of D-glucose and epidermal growth factor (EGF) display on the dynamic cellular behaviors of morphology and migration in a culture of human epithelial cells. The time-lapse observation revealed that the cells on the D-glucose/EGF-displayed substrate were endowed with enhanced migration, accompanied with periodic changes in morphology between round and stretched shapes. Immunofluorescence staining of phosphotyrosine PY20 and vinculin was conducted to determine the intracellular localization of phosphorylated tyrosine expression and focal contact formation, respectively. On the substrate displaying D-glucose and EGF, the cells exhibited increases in the levels of the expression of phosphorylated tyrosine and the formation of focal contacts not only at the cellular periphery but also in the cell body. These findings supported the consideration that the displayed D-glucose causes the cells to be in close contact with the surface via grasping glucose transporters on the cytoplasmic membrane. 相似文献
64.
High-Q nanocavities have been extensively studied recently because they are considered key elements in low-power photonic devices and integrated circuits. Here we demonstrate that ultrahigh-Q (>10(6)) nanocavities can be created by employing scanning probe lithography on a prepatterned line defect in a silicon photonic crystal. This is the first realization of ultrahigh-Q nanocavities by the postprocess modification of photonic crystals. With this method, we can form an ultrahigh-Q nanocavity with controllable cavity parameters at an arbitrary position along a line defect. Furthermore, the fabricated nanocavity achieves ultralow power all-optical bistable operation owing to its large cavity enhancement effect. This demonstration indicates the possibility of realizing photonic integrated circuits on demand, where various circuit patterns are written with a nanoprobe on a universal photonic crystal substrate. 相似文献
65.
The functions of scanning near-field optical microscopy (SNOM) were installed in high-resolution transmission electron microscopy (TEM) for cathodoluminescence spectroscopy and photoluminescence spectroscopy of individual nanostructures. Optical fiber probes used in SNOM were allowed to approach nanoparticles by piezomanipulation with simultaneous observation by TEM. As an application of this method, cathodoluminescence and photoluminescence from zinc oxide nanoparticles were measured at room temperature and 130 K. It was demonstrated that the present method directly provides the relationships between structural features of individual nanoparticles and spectra. 相似文献
66.
Characterization of electrical properties and photosensitivity of SnS thin films prepared by the electrochemical deposition method 总被引:2,自引:0,他引:2
Naoya Sato Masaya Ichimura Eisuke Arai Yoshihisa Yamazaki 《Solar Energy Materials & Solar Cells》2005,85(2):153-165
Using the electrochemical deposition (ECD) method, we prepared tin sulfide thin films, which are suitable for the absorption layer in solar cells because of its bandgap energy (1 eV). We first optimized pulse-form biasing for ECD by characterizing deposited samples with scanning electron microscope, Auger electron spectroscopy and X-ray diffraction measurements. Then, we investigated the electrical properties of deposited SnS thin films and the properties of contacts with several different metals. Furthermore, we observed the photoconductivity of the films by means of photoelectrochemical measurements. From these results, we confirmed that the SnS thin films show p-type conduction. 相似文献
67.
Hata K Kubota M Shimizu M Moriwaki H Kuno T Tanaka T Hara A Hirose Y 《International journal of molecular sciences》2011,12(11):8133-8145
The numbers of obese people and diabetic patients are ever increasing. Obesity and diabetes are high-risk conditions for chronic diseases, including certain types of cancer, such as colorectal cancer (CRC). The aim of this study was to develop a novel animal model in order to clarify the pathobiology of CRC development in obese and diabetic patients. We developed an animal model of obesity and colorectal cancer by breeding the C57BL/KsJ-db/db (db/db) mouse, an animal model of obesity and type II diabetes, and the C57BL/6J-Apc(Min/+) (Min/+) mouse, a model of familial adenomatous polyposis. At 15 weeks of age, the N9 backcross generation of C57BL/KsJ-db/db-Apc(Min/+) (db/db-Min/+) mice developed an increased incidence and multiplicity of adenomas in the intestinal tract when compared to the db/m-Min/+ and m/m-Min/+ mice. Blood biochemical profile showed significant increases in insulin (8.3-fold to 11.7-fold), cholesterol (1.2-fold to 1.7-fold), and triglyceride (1.2-fold to 1.3-fold) in the db/db-Min/+ mice, when compared to those of the db/m-Min/+ and m/m-Min/+ mice. Increases (1.4-fold to 2.6-fold) in RNA levels of insulin-like growth factor (IGF)-1, IRF-1R, and IGF-2 were also observed in the db/db- Min/+ mice. These results suggested that the IGFs, as well as hyperlipidemia and hyperinsulinemia, promoted adenoma formation in the db/db-Min/+ mice. Our results thus suggested that the db/db-Min/+ mice should be invaluable for studies on the pathogenesis of CRC in obese and diabetes patients and the therapy and prevention of CRC in these patients. 相似文献
68.
Takahiro Kochi Masahito Shimizu Tomohiko Ohno Atsushi Baba Takafumi Sumi Masaya Kubota Yohei Shirakami Hisashi Tsurumi Takuji Tanaka Hisataka Moriwaki 《International journal of molecular sciences》2013,14(7):14700-14711
Metabolic syndrome is associated with an increased risk of colorectal cancer. This study investigated the impact of hypertension, a component of metabolic syndrome, on azoxymethane (AOM)-induced colorectal carcinogenesis using SHRSP/Izm (SHRSP) non-diabetic/hypertensive rats and SHRSP.Z-Leprfa/IzmDmcr (SHRSP-ZF) diabetic/hypertensive rats. Male 6-week-old SHRSP, SHRSP-ZF, and control non-diabetic/normotensive Wister Kyoto/Izm (WKY) rats were given 2 weekly intraperitoneal injections of AOM (20 mg/kg body weight). Two weeks after the last injection of AOM, the SHRSP and SHRSP-ZF rats became hypertensive compared to the control WKY rats. Serum levels of angiotensin-II, the active product of the renin-angiotensin system, were elevated in both SHRSP and SHRSP-ZF rats, but only the SHRSP-ZF rats developed insulin resistance, dyslipidemia, and hyperleptinemia and exhibited an increase in adipose tissue. The development of AOM-induced colonic preneoplastic lesions and aberrant crypts foci, was significantly accelerated in both SHRSP and SHRSP-ZF hypertensive rats, compared to WKY normotensive rats. Furthermore, induction of oxidative stress and exacerbation of inflammation were observed in the colonic mucosa and systemically in SHRSP and SHRSP-ZF rats. Our findings suggest that hypertension plays a role in the early stage of colorectal carcinogenesis by inducing oxidative stress and chronic inflammation, which might be associated with activation of the renin-angiotensin system. 相似文献
69.
ANDREA P. RODRIGUEZ HIDETSUGU TSUJIGIWA MEHMET GUNDUZ BEYHAN CENGIZ NORIYUKI NAGAI RYO TAMAMURA SILVIA S. BORKOSKY TOHRU TAKAGI MIHO INOUE HITOSHI NAGATSUKA 《Biocell》2009,33(1):39-47
Progenitor cells play an important biological role in tooth and bone formation, and previous analyses during bone and dentine induction have indicated that they may be a good alternative for tissue engineering. Thus, to clarify the influence of the microenvironment on protein and gene expression, MDPC23 cells (mouse dental papilla cell line) and KUSA/A1 cells (bone marrow stromal cell line) were used, both in vitro cell culture and in intra-abdominal diffusion chambers implanted in 4-week-old male immunodefficient mice (SCID mice). Our results indicate that KUSA/A1 cells differentiated into osteoblast-like cells and induced bone tissue inside the chamber, whereas, MDPC-23 showed odontoblast-like characteristics but with a low ability to induce dentin formation. This study shows that MDPC-23 cells are especial cells, which possess morphological and functional characteristics of odontoblast-like cells expressing dentin sialophosphoprotein in vivo. In contrast, dentin sialophosphoprotein gene and protein expression was not detected in both cell lines in vitro. The intra-abdominal diffusion chamber appears as an interesting experimental model for studying phenotypic expression of dental pulp cells in vivo. 相似文献
70.
Five kinds of PEEK/CF composites, made by blending poly-ether-ether-ketone (PEEK) with three kinds of PAN type carbon fibers (CFs) and two kinds of pitch type CFs respectively, were injection-molded into gears. Their gear performance such as the load capability and the wear of tooth were evaluated. The wear properties of PEEK/CF gears extremely varied depending on the kinds of CFs, when the same type gears were combined and grease was initially applied. Also, the load capabilities were significantly influenced by the affinity between PEEK and CF. A composite gear reinforced with CF of the highest density indicated the highest load capability irrespective of the test conditions, due to the lowest abrasive property of the CF as well as the excellent affinity between PEEK and CF. Its load capability under a high temperature running condition was found to be superior to that of polyamideimide (PAI) composite gear or polyphenylenesulphide (PPS) composite gear. 相似文献