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排序方式: 共有4281条查询结果,搜索用时 31 毫秒
61.
Ha Ngoc Giang Kenji Kinashi Wataru Sakai Naoto Tsutsumi 《Macromolecular chemistry and physics.》2012,213(9):982-988
A new class of photorefractive (PR) composite based on a fully functionalized polymer with high phase‐stability is reported. The polymer containing non‐linear optical (NLO) chromophores and charge‐transporting carbazole moieties is synthesized by a polymer‐analogous reaction. The polymer is doped with plasticizer, NLO dye, and sensitizer to fabricate the PR composite. The NLO dye is the same as the NLO chromophore moiety in the polymer side chain. The PR performance of the composite is evaluated by degenerated four‐wave mixing and two‐beam coupling measurements. A diffraction efficiency of 30% at a relatively low applied electric field of 45 V μm?1 is achieved. Despite a high concentration of NLO dye, the composites show good stability for a long period without phase separation. 相似文献
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Miki Sato MD Wataru Yamadera MD PhD Masato Matsushima MD PhD Hiroshi Itoh MD PhD Kazuhiko Nakayama MD PhD 《Psychiatry and clinical neurosciences》2010,64(2):187-195
Aim: Twenty patients (14 of them women) suffering from psychophysiological insomnia (PPI) were enrolled for cognitive behavior therapy (CBT). The mean age of the patients was 56.9 years, and the mean duration of insomnia morbidity was 8.9 years. Each received individual combined CBT treatments consisting of stimulus control, sleep reduction, cognitive therapy and sleep hygiene education over a period of 1 month. Methods: Just before the CBT and after its completion, sleep measurements were conducted that involved (i) sleep logs, Dysfunctional Beliefs and Attitudes about Sleep Scale (DBAS), and the Pittsburgh Sleep Quality Index (PSQI); (ii) actigraphy measurement; (iii) dissociation between subjective and objective evaluation of sleep calculated from sleep logs and actigraphy results; and (iv) correlation between DBAS and the aforementioned sleep parameters. Because the intention was to focus on patients' incorrect cognition about sleep, the definition ‘changes in dissociation between the sleep log and actigraphically measured sleep’ was used as the primary outcome and ‘changes in DBAS score’ as the secondary outcome. Results: After the CBT the following was found: (i) underestimation by PPI patients of the objective evaluation of sleep; (ii) a decrease in the dissociation between the subjective and objective evaluation of sleep; (iii) improvement of the DBAS; and (iv) improvement of sleep logs and actigraphy measurements. Moreover, there was a correlation between the improvement of PSQI, sleep logs and DBAS. Conclusion: CBT for insomnia is able to redress incorrect cognition about sleep, leading to improvement of the disorder. 相似文献
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Hiyama T Tanaka S Yoshihara M Sasao S Kose K Shima H Tuncel H Ueno Y Ito M Kitadai Y Yasui W Haruma K Chayama K 《Journal of gastroenterology and hepatology》2004,19(7):756-760
BACKGROUND: Gastric cancer can progress through two pathways of genomic instability: chromosomal (CIN) and microsatellite instability (MSI). It is hypothesized that these two pathways are not always independent and that some tumors show overlap between these two mechanisms. METHODS: A total of 98 sporadic gastric cancers were classified based on their MSI status, using microsatellite assay with BAT26. Evidence for CIN was investigated by identifying loss of heterozygosity (LOH) events on chromosome arms, 5q, 10p, 17p, 17q, and 18q, which are regions harboring tumor suppressor genes that are significant in gastric cancer development. RESULTS: Twelve tumors (12%) showed high-frequency MSI (MSI-H). Overall, 43 of the tumors (44%) had at least one LOH event, with most frequent chromosomal losses observed on 10p and 18q (30%, respectively), followed by 5q (21%), 17p (14%), and 17q (12%). Interestingly, overlap was observed between CIN and MSI pathways. Of 43 cancers with LOH events, four (9%) were also MSI-H. It was also found that 48% of cancers without MSI-H had no LOH events identified, comprising a subgroup of tumors that were not representative of either of these two pathways of genomic instability. CONCLUSION: These results suggest that molecular mechanisms of genomic instability are not necessarily independent and may not be fully defined by either the MSI or CIN pathways in sporadic gastric cancers. 相似文献
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Shin-ichi Ando Keita Odashiro Toshiaki Ashihara Hiroshi Ando Wataru Mitsuoka Hirofumi Tagawa Takaya Fukuyama 《Heart and vessels》1994,9(2):104-107
Summary We angiographically documented coronary vasospasm which resulted in myocardial infarction during the acute phase of aortic dissection (Stanford A). Coronary and aortic angiography performed at admission of the patient revealed complete occlusion of the right coronary artery and dissection of the aorta. Intracoronary injection of isosorbide dinitrate and intravenous administration of verapamil opened the occluded right coronary artery and blood flow was fully restored. We conclude that, in this case of aortic dissection, the severe stimulation by the aortic dissection brought about vasospasm of the right coronary artery which was the major cause of myocardial infarction. This is the first case report showing clear evidence that myocardial infarction is brought about by vasospasm associated with aortic dissection. 相似文献
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Kaneki T Kawashima A Akamatsu T Tanaka N Kubo K Koizumi T Sekiguchi M Hosaka N Honda T Koike S Adachi W 《Journal of gastroenterology》1999,34(2):253-259
We report a rare case of immunoblastic lymphadenopathy (IBL)-like T-cell lymphoma complicated by multiple gastrointestinal
involvement, which appeared to be ameliorated by chemotherapy but resulted in perforative peritonitis. A 66-year-old Japanese
woman who had generalized lymphadenopathy and eruptions was admitted to our hospital because of bloody stool. Colonoscopic
examination revealed hemorrhagic ulcers in the terminal ileum and a saucer-like ulcer in the cecum. Gastrointestinal endoscopy
revealed several ulcerative or elevated lesions in stomach and duodenum. Biopsy specimens of these lesions and of a lymph
node showed characteristic histological features of IBL-like T-cell lymphoma. The initial treatment with prednisolone (PSL)
and cyclophosphamide (CPA) was effective. Six months after the treatment, however, she developed bloody stool again caused
by multiple ulcerative lesions in the large intestine. The recurrence of the disease was determined histologically, and four
courses of CPA, PSL, vinblastine sulfate and doxorubicin hydrochloride (CHOP) therapy were administered. One month after completing
the CHOP therapy, she developed intestinal obstruction and then acute peritonitis resulting from perforation at an ulcer scar
in the jejunum. Surgical treatment was successful, and histological examination demonstrated no lymphoma cells in the resected
specimen. A gastrointestinal perforation should be recognized as a potential complication of IBL-like T-cell lymphoma, even
during remission.
(Received: June 24, 1998; accepted: Oct. 23, 1998) 相似文献
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