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排序方式: 共有338条查询结果,搜索用时 15 毫秒
171.
Ultra-long-span 500 km 16/spl times/10 Gbit/s WDM unrepeatered transmission without dedicated fibre for remote pumping is successfully demonstrated for the first time. Enabling technologies are the RZ-DPSK format, forward pumped Raman amplification, and second-order backward pumped Raman amplification in combination with enlarged effective area SMF and conventional SMF. 相似文献
172.
M Sugiyama Y Atomi S Naka Y Nagashima K Kozawa N Wada 《Canadian Metallurgical Quarterly》1998,45(22):1141-1144
One patient with a choledochal cyst and anomalous pancreaticobiliary junction had pancreatic transection causing bile peritonitis. Intraoperative cholangiopancreatography revealed this anomaly. In another patient with pancreas divisum, cannulation of the minor papilla (ERCP) demonstrated focal stenosis of the dorsal pancreatic duct, corresponding to the site of the minor laceration. The possibility of a coexisting pancreatobiliary anomaly should be considered in the diagnosis of pancreatic trauma, particularly in terms of the interpretation of pancreatograms. 相似文献
173.
K Furuse N Naka M Takada E Kinuwaki S Kudo Y Takada M Yamakido H Yamamoto M Fukuoka 《Canadian Metallurgical Quarterly》1997,54(4):298-303
BACKGROUND AND AIMS: Hysterectomy is believed to be associated with disturbed defecation, mainly constipation. This study longitudinally describes bowel function in women submitted for hysterectomy. MATERIAL AND METHODS: Rectoanal manovolumetry, whole gut transit time and detailed interviews on bowel function and dyspareunia were performed preoperatively and at 3 and 11-18 months after hysterectomy in 42 women. Twenty healthy women matched for age and parity served as manovolumetry controls. RESULTS: No significant changes in anal sphincter pressures could be demonstrated, neither early nor late after hysterectomy. Transit time was unaffected. All but one of the patients claimed that they had been suffering from one or more of the following symptoms; abdominal pain, distension, constipation and dysparenuia. While postoperative interviews revealed a significant improvement with respect to abdominal pain and dyspareunia (P < 0.01) after 3 and 11-18 months, improvement of abdominal distension and constipation proved to be transient only. CONCLUSION: Simple abdominal hysterectomy appears not to interfere adversely with bowel function. On the contrary many patients were relieved from abdominal pain present before operation. 相似文献
174.
175.
Michiaki Mori Yoneyoshi Kitagawa Ryosuke Kodama Hideaki Habara Manabu Iwata Saiji Tsuji Kenji Suzuki Kiyonobu Sawai Kazuo Tanaka Yoshiaki Kato Kunioki Mima 《Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment》1998,410(3):1290-372
The 30 TW GEKKO MII short pulse laser (25 J in 0.71 ps at 1 μm) is completed and is used for fast ignitor and particle accelerator research. The photon pressure of the laser at 1017-1018 W/cm2 pushed the critical and quarter critical density plasmas forward, resulting in the strong red shifts of the second (2ω0) and three-halves (3ω0/2) harmonic emissions backscattered from CH or CD planes. A few hundred keV proton and deuteron emissions are also observed from CD planes. 相似文献
176.
Qi Yan Le Van Vang Chau Nguyen Quoc Khanh Hideshi Naka Tetsu Ando 《Journal of chemical ecology》2014,40(6):590-598
The sweet potato vine borer moth, Omphisa anastomosalis (Pyraloidea: Crambidae), is a serious pest in tropical and subtropical Asia-Pacific regions. In previous work using a population from Okinawa, Japan, (10E,14E)-10,14-hexadecadienal (E10,E14-16:Ald) was identified as the major pheromone component, with hexadecanal, (E)-10-hexadecenal, and (E)-14-hexadecenal as minor components. However, traps baited with the synthetic compounds were less effective at attracting males in the field than those baited with virgin females. While Pyraloidea females usually produce only Type I pheromone components (unsaturated fatty alcohols and their derivatives), the pheromones of some Pyraloidea species have been shown to involve a combination of both Type I and Type II components (unsaturated hydrocarbons and their epoxides). We examined an extract of the pheromone glands of female O. anastomosalis from Vietnam by gas chromatography coupled to mass spectrometry and detected (3Z,6Z,9Z)-3,6,9-tricosatriene (Z3,Z6,Z9-23:H) in addition to the compounds identified previously. All four isomers of 10,14–16:Ald were synthesized. A mixture of synthetic E10,E14-16:Ald and Z3,Z6,Z9-23:H in a ratio of 1:0.2–1:2 was attractive to male moths in Vietnam, indicating the strong synergistic effect of the Type II compound. Addition of the other minor pheromone components to the binary blend did not increase the number of male moths captured. Combinations of Z3,Z6,Z9-23:H with the other three geometrical isomers of E10,E14-16:Ald attracted no males, further substantiating the 10E,14E configuration of the natural diene component. E10,E14-16:Ald mixed with other polyunsaturated hydrocarbons showed that mixtures that included a C21 triene, a C22 triene, or a C23 pentaene attracted as many males as did the mixture with Z3,Z6,Z9-23:H. The identification of a highly attractive sex pheromone will help in developing efficient strategies for monitoring and control of O. anastomosalis populations in sweet potato fields. 相似文献
177.
Cylindrical deep drawing tests were performed on a fine-grain aluminium-magnesium alloy (5083-O) sheet at various forming speed (0.2~500 mm · min-1) and temperatures (298, 353, 423 and 453 K). It was found that limiting drawing ratio (LDR) is strongly affected by temperature while its value increases with decreasing forming speed independent of the test temperature. The LDR reaches minimum value at 353 K. It is associated with the maximum flow stress registered for this particular temperature and caused in turn by dynamic strain ageing. 相似文献
178.
R Matsumoto M Naka N Omawari B Fujitani H Aishita 《Canadian Metallurgical Quarterly》1993,52(15):1257-1264
We studied the effect of OP-41483.alpha-CD, a stable prostacyclin analog, on, 15-HPETE induced bovine endothelial cell dysfunction, which was assessed by measuring a number of endothelial cells attached to plastic plates. 15-HPETE decreased the number of attached endothelial cells in a concentration- and time-dependent manner. OP-41483.alpha-CD and PGI2 significantly inhibited 15-HPETE induced dysfunction of the cells at a concentration of more than 10(-9)M. Besides, DDA (10(-6) - 10(-4)M) an adenylate cyclase inhibitor, diminished the inhibitory effect of OP-41483.alpha-CD on 15-HPETE induced cell dysfunction in a concentration-dependent manner. Furthermore, OP-41483.alpha-CD increased cAMP levels in the endothelial cells in the range of 10(-10) to 10(-8)M in a dose-dependent manner. These data suggest that OP-41483.alpha-CD could exert an inhibitory action on 15-HPETE induced endothelial cell dysfunction via partly increasing its effect on the intracellular cAMP level. 相似文献
179.
180.
M Hori H Sato M Karita K Kodama N Hoki T Hayashi M Naka S Nanto Y Yamada T Kamada 《Canadian Metallurgical Quarterly》1994,9(5):249-253
The long-term effect of calcium channel blockers on chronic heart failure is disappointing, probably because of reflex sympathetic activation through arterial vasodilation. However, nilvadipine may be beneficial for treatment of chronic heart failure since this drug has minimal effects on sympathetic activation. In this study, the effects of 12-week administration of nilvadipine or placebo on symptoms of heart failure and cardiac function were investigated in 23 patients with mild-to-moderate chronic heart failure in a double-blind trial. The patients were randomly assigned to either a nilvadipine group (16 mg daily) or a placebo group. Intergroup comparisons did not show significant differences in any parameters. Serious adverse effects were not observed during the study. Thus, this study failed to show any beneficial effect of nilvadipine in the long-term treatment of patients with chronic heart failure. We conclude that the long-term administration of nilvadipine (16 mg daily) is neither effective nor harmful in the treatment of patients with chronic heart failure. 相似文献