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991.
Tsuyako Sakamaki Motohiko Hara Kazunori Kayaba Kazuhiko Kotani Shizukiyo Ishikawa 《Journal of epidemiology / Japan Epidemiological Association》2016,26(2):71-75
Background
Previous studies on the association between coffee consumption and subarachnoid hemorrhage (SAH) have provided inconsistent results. We examine the risk of SAH from coffee consumption in a Japanese population.Methods
Our analyses were based on the Jichi Medical School Cohort Study, a large-scale population-based prospective cohort study. A total of 9941 participants (3868 men and 6073 women; mean age 55 years) with no history of cardiovascular disease or carcinoma were examined. Participants were asked to choose one of five options to indicate their daily coffee consumption: none, less than 1 cup a day, 1–2 cups a day, 3–4 cups a day, or 5 or more cups a day. The incidence of SAH was assessed independently by a diagnostic committee. Cox proportional hazards models were used to calculate hazard ratios (HRs) and their 95% confidence intervals (CI) after adjustment for age and sex (HR1) and for additional potential confounders (HR2).Results
During 10.7 years of follow-up, SAH occurred in 47 participants. When compared with the participants who consumed less than 1 cup of coffee a day, the HR of SAH was significantly higher in the group who consumed 5 or more cups a day in both models (HR1 4.49; 95% CI, 1.44–14.00; HR2 3.79; 95% CI, 1.19–12.05).Conclusions
The present community-based cohort study showed that heavy coffee consumption was associated with an increased incidence of SAH after adjusting for age, sex, and multiple potential cardiovascular confounders.Key words: coffee consumption, subarachnoid hemorrhage, community-based cohort study 相似文献992.
993.
Takehiro Kawauchi Tsubasa Osawa Shunichiro Matsumura Takuto Mori Nobuyuki Furukawa Kazunori Ishikawa Koju Iwasaki Tsutomu Takeichi 《Macromolecular chemistry and physics.》2019,220(1)
A novel polyfunctional benzoxazine monomer, OP‐a , is synthesized from aniline, formaldehyde, and an oligonuclear phenolic compound (OP) with a 4,4′‐dimethylenebiphenyl group as the phenol linker. After thermal curing of OP‐a up to 240 °C, a brown‐colored, transparent polybenzoxazine ( POP‐a ) film is obtained. The mechanical and thermal properties of the POP‐a film are investigated by tensile test, dynamic mechanical analysis (DMA), and thermogravimetric analysis (TGA). The POP‐a film is extremely tough compared with a typical polybenzoxazine ( PB‐a ) film. The elongation at break of the POP‐a film is 7.6%, which is surprisingly large for the highly cross‐linked thermoset. The high cross‐link density is suggested from the very high storage modulus (over 1 GPa) above the glass transition temperature (T g) observed by DMA. The T g of POP‐a is also improved significantly to T g = 223 °C, which is approximately 50 °C higher than that of PB‐a . Moreover, TGA reveals that the thermal stability of POP‐a is also enhanced. 相似文献
994.
Lavigne GJ Huynh N Kato T Okura K Adachi K Yao D Sessle B 《Archives of oral biology》2007,52(4):381-384
This is a short review paper presenting hypothesis to explain the mechanism that may be involved in the genesis of sleep bruxism (SB). In humans, SB is a repetitive sleep movement disorder mainly characterized by rhythmic masticatory muscle activity (RMMA) at a frequency of 1Hz and by occasional tooth grinding. Until recently, the mechanism by which RMMA and SB episodes are triggered has been poorly understood. It is reported that during light sleep, most SB episodes are observed in relation to brief cardiac and brain reactivations (3-15s) termed "micro-arousals". We showed that RMMA are secondary to a sequence of events in relation to sleep micro-arousals: the heart (increase in autonomic sympathetic activity) and brain are activated in the minutes and seconds, respectively, before the onset of activity in suprahyoid muscles and finally by RMMA in jaw closing masseter or temporalis muscles. In non-human primate study, we have shown that the excitability of cortico-bulbar pathways is depressed during sleep; no rhythmic jaw movements (RJM) are observed following intracortical microstimulation (ICMS) of cortical masticatory area (CMA) during sleep compared to the quiet awake state. The above results suggest that the onset of RMMA and SB episodes during sleep are under the influences of brief and transient activity of the brainstem arousal-reticular ascending system contributing to the increase of activity in autonomic-cardiac and motor modulatory networks. 相似文献
995.
Adhesion promoting monomers for precious metals, 2,3-epithiopropyl methacrylate (EP1MA), 4,5-epithiopentyl methacrylate (EP3MA), 9,10-epithiodecyl methacrylate (EP8MA), 10,11-epithioundecyl methacrylate (EP9MA), 9,10-epithiodecyl 4-vinylbenzoate (EP8VB), 2,3-epithiocyclohexyl methacrylate (EPCHMA), and 3,4-epithiobutyl 2,2-bis(methacryloyloxymethyl)-propionate (EP2BMA), were used as surface treatment agents for pure gold to improve the durability of resin bonds against water. Treated specimens were butt-jointed together with MMA-PMMA resins, and tensile bond strength was measured after 2,000 thermal cycles in water. Bond strength to precious metal alloys was also determined under the same condition to clarify the influence of metal composition. The adhesion performance of thiirane monomers to pure gold highly depended on their chemical structure. EP3MA, EP8MA, EP9MA, EP8VB, and EP2BMA showed excellent performance, while EP1MA exhibited a moderate one and EPCHMA a poor one. The comparison of pure gold with precious metal alloys revealed the usefulness of pure gold as a standard, common adherend for bond strength evaluations. 相似文献
996.
Norio Isoda Kenichi Ido Chiaki Kawamoto Takanori Suzuki Nobuhiko Nagamine Kazunori Ono Yoshiaki Sato Yoshinari Kaneko Machio Kumagai Ken Kimura Kentaro Sugano 《Journal of gastroenterology》1999,34(3):372-375
It remains controversial whether patients with gallstones with acute cholecystitis should be operated on early, or whether
surgery should be delayed until the acute phase subsides. To help resolve this question, we retrospectively studied 109 patients
with acute cholecystitis, 56 of whom underwent laparoscopic cholecystectomy after acute cholecystitis had subsided (delayed
group) and 53 of whom underwent early laparoscopic cholecystectomy—within 7 days after admission (early group). On admission,
the inflammatory findings in the two groups were very similar; however, at operation, the inflammatory findings were alleviated
in the delayed group, while they remained unchanged in the early group. The mean operative time for the two groups was very
similar. As for intraoperative complications, there was no conversion to laparotomy in either group, and there were no major
complications in either group. The total hospital stay was 37.7 ± 14.4 days for the delayed group and 12.7 ± 2.0 days for
the early group, showing a highly significant difference (P < 0.001). Early laparoscopic cholecystectomy seems to be better than delayed treatment for patients with gallstones with
acute cholecystitis.
Received: April 27, 1998/Accepted: November 27, 1998 相似文献
997.
998.
Characterization of cytokine expression in the rectal mucosa of ulcerative colitis: correlation with disease activity 总被引:12,自引:0,他引:12
999.
Comparison of the distribution of fluorine-18 fluoromisonidazole, deoxyglucose and methionine in tumour tissue 总被引:4,自引:3,他引:1
Kazuo Kubota Masao Tada Susumu Yamada Katsuyoshi Hori Sachiko Saito Ren Iwata Kazunori Sato Hiroshi Fukuda Tatsuo Ido 《European journal of nuclear medicine and molecular imaging》1999,26(7):750-757
14 C-2-deoxyglucose (2DG) and 14C-methionine (Met). The study was performed using control rats with the AH109A tumour and rats with the same tumour under
local hypoxia. Tumour uptake of FMISO was constant between 30 min and 2 h after injection, and the tumour to muscle ratio
was 2 from 2 to 4 h. A tumour study with FMISO was scheduled at 2 h. Double-tracer autoradiography of the tumour demonstrated
that in the areas of high FMISO uptake, there was low uptake of Met, while areas of low FMISO uptake showed high Met uptake.
FMISO showed high grain density in the rim of the tumour surrounding the necrotic area. 2DG showed a more uniform distribution
over the entire section of viable cells. The mean uptake of FMISO by hypoxic, radioresistant tumours was significantly higher
than that by the control tumours (P<0.05), while both 2DG and Met uptake by the control tumours was higher than uptake by hypoxic tumours. When individual tumours
were examined, the uptake of FMISO was inversely correlated with that of Met (r = –0.507, P<0.02), while 2DG showed almost uniform uptake with no significant correlation to FMISO. In conclusion, hypoxic and radioresistant
tumours could be identified by increased FMISO uptake in our model, consistent with findings reported by others. We found
a large overlap in the distribution of FMISO and 2DG within the tumour, but only a small overlap in the distribution of FMISO
and Met. A combination of FMISO and other tracers in positron emission tomography or single-photon emission tomography studies
might be more helpful than single-tracer studies in predicting the response of tumour tissues to radiotherapy.
Received 27 November 1998 and in revised form 3 February 1999 相似文献
1000.
Angiomatous variant of pleomorphic xanthoastrocytoma in a patient with a 20-year history of epilepsy
Yasuo Sugita Itsurou Hayashi Takachika Aoki Minoru Shigemori Minoru Morimatsu Yuji Okamoto Kazunori Kajiwara 《Neuropathology》1999,19(2):190-195
The angiomatous variant of the pleomorphic xantho-astrocytoma (PXA) is a morphological subtype of PXA that is characterized by the presence of large numbers of tiny blood vessels with variable wall thicknesses. A case of an angiomatous variant of PXA occurring in the temporal lobe of a 43-year-old man is presented. The patient had a 20-year history of seizures. Considering the clinical course and intra-operative electro-encephalography findings, it appears that this tumor was the epileptic focus in this patient and that it had been present for 20 years. Histopathologically, various degenerative changes, such as microcystic changes, calcification and hyaline thickening of vessel walls were seen in the tumor. In particular, obvious vascularity in the tumor and secondary vascular degenera-tion should be related to gradual growth and benign clinical course of an angiomatous variant of PXA. 相似文献