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961.
962.
K Ishihama M Kogo H Koizumi K Nomura S Tanaka T Yamanishi A Enomoto 《Canadian Metallurgical Quarterly》2003,145(1):163-166
Development of neural circuits generating fetal oral-motor activity was characterized in an in vitro isolated brainstem block preparation. Rhythmical trigeminal activity (RTA) at E20-E21 resembled either the pattern or rhythm of neonatal RTA. Conversely, at E18-E19, RTA displayed a different pattern of discharge from neonatal RTA, and output was not regular but intermittent with another slow rhythm. 相似文献
963.
K Yoshikawa Y Suzaki M Tanaka S Arihara SK Nigam 《Canadian Metallurgical Quarterly》1997,60(12):1269-1274
Four new oleanane-type triterpene glycosides, pithedulosides H-K (1-4), were isolated from the seeds of Pithecellobium dulce. Their structures were established by extensive NMR experiments and chemical methods. Compounds 1-3 comprised acacic acid as the aglycon and either monoterpene carboxylic acid and its xyloside or monoterpene carboxylic acid as the acyl moiety at C-21. The oligosaccharide moieties linked to C-3 and C-28 were determined as alpha-L-arabinopyranosyl-(1-->2)-alpha-L-arabinopyranosyl-(1 -->6)- [beta-D-glucopyranosyl-(1-->2)]-beta-D-glucopyranosyl and alpha-L-arabinofuranosyl-(1-->4)-[beta-D-glucopyranosyl-(1-->3)]-alpha- rhamnopyranosyl-(1-->2)-beta-D-glucopyranosyl ester, respectively. Compound 4 was established as an echinocystic acid 3-O-glycoside having the same sugar sequences as 1-3. Also obtained in this investigation was the known compound 5, which was identified as echinocystic acid 3-O-beta-D-xylopyranosyl- (1-->2)-alpha-L-arabinopyranosyl-(1-->6)-[beta-D-glucopyranosyl-(1 -->2)]- beta-D-glucopyranoside. 相似文献
964.
The present paper reviews the results oblained by the authors in the last three years. By applying in-situ (pamp and probe) EXAFS to reversible photostructural changes in chalcogenide vitreous semiconductors we have found an increase
in the average coordination number of selenium species in the photoexcited state which comes from the formation of dynamic
interchain bonds. Subsequent bond rupture, studied by optically induced ESR, results in the formation of over-and undercoordinated
ESR-active defects, which are further transformed into charged valence-alternation pairs. Annealing close to the glass-transition
temperature results in recovery of the initial structure. Relationship between the detected structural changes and photodarkening
is also discussed.
Fiz. Tekh. Poluprovodn. 32, 899–904 (August 1998)
Published in English in the original Russian journal. Reproduced here with stylistic changes by the Translation Editor. 相似文献
965.
BACKGROUND: Angiosarcomas are uncommon soft tissue neoplasms with a predilection for skin and superficial soft tissues. CASES: Two cases of angiosarcoma occurred at unusual sites, the parotid gland and lung. The parotid lesion was characterized by malignant cells present singly, in loose groups, in tight three-dimensional aggregates and in acinar formation initially misinterpreted as an adenocarcinoma. The lung mass showed malignant cells in association with vascular endothelium, suggestive of angiosarcoma. Both cases were negative for Ulex europaeus and Factor VIII-related protein but demonstrated strong immunopositivity for CD31, a highly specific endothelial marker. CONCLUSION: In the absence of vasoformative structures, important diagnostic pitfalls are pseudovascular adenoid squamous cell carcinoma, poorly differentiated adenocarcinoma, melanoma and lymphoma. Immunocytochemical studies and clinical history are essential to the correct diagnosis. 相似文献
966.
SS Huang Q Liu FE Johnson Y Konish JS Huang 《Canadian Metallurgical Quarterly》1997,272(43):27155-27159
Transforming growth factor beta (TGF-beta) has been implicated in the pathogenesis of various human diseases. Synthetic TGF-beta antagonists therefore could have therapeutic utility. Here we show the development of such compounds. Three synthetic pentacosapeptides designated beta125-(41-65), beta225-(41-65), and beta325-(41-65), whose amino acid sequences correspond to the 41st to 65th amino acid residues of TGF-beta1, TGF-beta2, and TGF-beta3, respectively, inhibit the binding of 125I-labeled TGF-beta isoforms to TGF-beta receptors in mink lung epithelial cells with IC50 of approximately 0.06-2 microM. beta125-(41-65) blocks TGF-beta1-induced growth inhibition and TGF-beta1-induced plasminogen activator inhibitor-1 expression in these cells. The variants designated beta125-(41-65)W52A/D55A and beta325-(41-65)R52A/D55A, in which both Trp52/Arg52 and Asp55 are replaced by alanine residues, do not have TGF-beta antagonist activity. Multiple conjugation of beta125-(41-65) to carrier proteins enhances its antagonist activity but also confers partial agonist activity as measured by DNA synthesis inhibition. These results suggest that the (W/R)XXD motif is important for the activities of these TGF-beta peptide antagonists and that this motif may be the active site sequence of TGF-beta. 相似文献
967.
This paper describes a new class of saturable absorber device based on single-wall carbon nanotube (SWNT)-the saturable absorber incorporating nano tube (SAINT). The device possesses ultrafast optical properties comparable to that of the industrial standard semiconductor saturable absorber mirror (SESAM). Passively mode-locked picosecond fiber lasers in different configurations are demonstrated using SAINTs as mode lockers. This is the first demonstration of optical pulsed lasers based on the carbon nanotube technology, and the first practical application of carbon nanotubes in the field of applied optics. 相似文献
968.
It has been noted that the voltage of connection points rises according to the reverse power flow when grid‐connected photovoltaic systems are concentrated in distribution systems in residential areas. When this happens, the photovoltaic system may control the power generation output to maintain a suitable voltage for the connection point. Designing a demand area power system aiming at free access to a distributed power supply for energy‐effective practical use requires a precise understanding of this problem. When analyzing photovoltaic systems mainly connected to low‐voltage systems, we looked for a method of analysis in which the high‐voltage systems and the low‐voltage single‐phase three‐wire systems are unified. This report concerns use of the indication method between nodes using power flow calculation, for the purpose of developing a technique of analyzing unified high‐voltage systems and low‐voltage single‐phase three‐wire systems. © 2004 Wiley Periodicals, Inc. Electr Eng Jpn, 147(3): 49–62, 2004; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.10255 相似文献
969.
Hayashida S. Tanaka T. Morishita H. Koyanagi Y. Fujimoto K. 《Electronics letters》2004,40(24):1514-1516
A built-in folded monopole antenna for handsets (BFMA) is introduced and investigated. The characteristics of the BFMA are compared with those of a planar inverted-F antenna (PIFA), which is one of the conventional handset antennas. As a result, it has been confirmed that the BFMA has smaller size and wider bandwidth compared with the PIFA. 相似文献
970.
OBJECTIVES: To estimate and compare recurrence rates, index of recurrence, and disease-free interval in patients with superficial recurrent bladder cancer receiving bacille Calmette-Guérin (BCG) or interferon (IFN) for immunoprophylaxis. METHODS: One hundred twenty-two patients with recurrent superficial Stage pT1, grade 1 to 3 tumors were enrolled in a randomized, prospective, multicenter trial with two treatment arms of endovesical immunoprophylaxis: 150 mg of BCG versus 54 MU of recombinant IFN-alpha-2a. Administration was weekly during the first month, biweekly for 2 months, and monthly for 9 months. Both groups were similar with regard to tumor stage, grade, size, and number. RESULTS: Sixty-one patients were evaluable in the BCG group and 49 in the IFN group. Tumors recurred in 34 (69.4%) of 49 patients in the IFN group (890 months of follow-up) and in 24 (39.3%) of 61 in the BCG group (1272 months of follow-up). The total number of recurrences (28 for BCG, 47 for IFN), disease-free interval (mean 19.3 months for BCG, 15.3 months for IFN), and index of recurrence (2.2 for BCG, 5.5 for IFN) were statistically significant (P = 0.001) in favor of BCG. Progression to invasive carcinoma was similar in both study arms. Neither systemic nor local side effects were seen in the IFN group. However, the previously reported toxicity of BCG was confirmed. CONCLUSIONS: According to our trial, BCG remains the most efficacious agent for immunoprophylaxis of recurrent superficial bladder tumors. 相似文献