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排序方式: 共有1908条查询结果,搜索用时 15 毫秒
81.
A Mori S Tamura T Katsuno Y Nishimura T Itoh K Saheki H Takatsuka H Wada Y Fujimori T Okamoto Y Takemoto E Kakishita 《Canadian Metallurgical Quarterly》1999,6(1):55-58
STUDY OBJECTIVE: To evaluate the efficacy of conservative laparoscopic surgery in a series of patients with stage III-IV endometriosis. DESIGN: Prospective study (Canadian Task Force classification II-1). SETTING: University-affiliated hospital. PATIENTS: All 141 women who underwent conservative operative laparoscopy for stage III-IV endometriosis between January 1993 and December 1996 and were followed for a minimum of 6 months. INTERVENTIONS: Laparoscopic procedures performed with scissors, bipolar coagulation, and hydrodissection. MEASUREMENTS AND MAIN RESULTS: Clinical examination, transvaginal ultrasonography, and pain questionnaire were scheduled every 6 months postoperatively. The cumulative proportion of pregnant patients and cumulative recurrence rate were calculated by Kaplan-Meier method. Twenty-five women (44%) with infertility became pregnant. Twenty-three (51%) had stage III and two (16.7%, p <0.05) had stage IV endometriosis. The 24-month cumulative pregnancy rate was 57.5%. Thirty-one women (22%) reported pain recurrence during follow-up. Five (3.5%) recurrences were confirmed by histologic examination and eight (5.7%) were documented only by clinical and ultrasonographic findings. No recurrence occurred in the first 6 months of follow-up. CONCLUSION: Operative laparoscopy seems to be effective treatment for stage III endometriosis. A larger series with longer follow-up is necessary to clarify its role in the management of stage IV disease. (J Am Assoc Gynecol Laparosc 6(1):55-58, 1999) 相似文献
82.
In this paper, two novel structures of porous silicon (PS) light-emitting diodes (LEDs) are proposed aiming at the reduction of series resistance, Rs. The basic idea of the novel structures is to suppress the excessive growth of nanoporous silicon (nano-PS) layer that is electroluminescence- (EL-) active but highly resistive. The initial wafer of the first structure consists of a lightly-doped layer stacked on a highly-doped substrate. As a consequence of anodization, nano-PS layer is formed only in the lightly-doped layer, while meso-PS layer with moderate resistivity is formed in the highly-doped substrate. The second structure consists of alternately stacked nano- and meso-PS layers, since it is expected that multiple thin nano-PS layers connected in series are less resistive than a single thick nano-PS layer. Preliminary experimental results proved the effectiveness of these novel structures on the reduction of Rs. 相似文献
83.
The transformation conditions of an Fe-based polycrystalline shape memory alloy are determined experimentally under the multiaxial stress state. The martensite start condition is represented as an oval conical surface in the axial stress-shear stress-temperature space, meaning the transformation condition is not the von Mises type condition in plasticity and clearly depends on the third invariant of the stress tensor. The austenite start and finish conditions are also determined as the planes in the multiaxial stress-temperature space. The uniaxial stress-strain-temperature hysteretic behavior determined under the uniaxial thermomechanical loads is simulated by introducing the internal state variables which represent the status of the microscopic internal structures. 相似文献
84.
The far-field pattern measuring technique is used to measure the wavelength dependence of the mode field radius in standard single-mode fibres. Chromatic dispersion calculated from these results is shown to be accurate using as few as three lasers. Both theoretical and experimental results are presented. 相似文献
85.
Syuji Fujii Yukihiro Nishimura Atsushi Aichi Soichiro Matsuzawa Yoshinobu Nakamura Kensuke Akamatsu Hidemi Nawafune 《Synthetic Metals》2010,160(13-14):1433-1437
Polyaniline–silver nanocomposites were synthesized in the form of colloidal particles by the facile one-step aqueous chemical oxidative dispersion polymerization of aniline using silver nitrate as an oxidant and poly(vinyl alcohol) as a colloidal stabilizer. Aniline monomer was oxidized by silver ions, yielding polyaniline and elemental Ag simultaneously. The synthesized nanocomposite particles were colloidally stable over 2 years and transmission electron microscopy studies indicated the production of spherical, plate and rod-shaped polyaniline–silver nanocomposite particles with a silver core–polyaniline shell morphology. The conductivity of a pressed pellet of the nanocomposite particles using the conventional four-point probe technique was 1.4 × 10?2 S/cm at 25 °C. The nanocomposite particles behaved as a ‘colored’ particulate emulsifier for the stabilization of transparent oil-in-water emulsions. 相似文献
86.
87.
Yukao Tanaka Hidetoshi Nishigaito Hiroo Konishi Masashi Nishimura 《Electrical Engineering in Japan》2001,136(3):49-57
An advanced real‐time power system simulator consisting of a conventional real‐time analog simulator and a real‐time digital simulator has been developed. EMTP simulations were carried out to verify the advanced power system simulator concept and to evaluate the effects of various parameters. A prototype of the advanced power system simulator using the Bergeron method was tested. The test results confirmed the feasibility of the real‐time power system simulator. © 2001 Scripta Technica, Electr Eng Jpn, 136(3): 49–57, 2001 相似文献
88.
Naomi Norquay 《Pedagogy, Culture & Society》2000,8(1):7-21
Taking John Willinsky's observation that in Canadian identity politics, the question 'who am I?' often necessitates the additional question 'where is here?' (Willinsky, 1998), this article examines excerpts from interviews with a group of teacher education students in order to explore how they used family (hi)stories about 'country of origin' in the construction of their identities. Making 'country of origin' problematic, the article also examines the limits and possibilities of being and becoming Canadian. 'Where are you from?' complicates and challenges the entitlement to belong. Drawing on critiques by Canadian educators, the article challenges the widely held significations given to Canadian immigration and to official policies of multiculturalism. By juxtaposing data from eight interviews, the issue of racial identity is explored, in terms of how it appears or does not appear in the stories the students tell. These juxtapositions highlight the unofficial intersections between Canadian identity, race and ethnicity. 相似文献
89.
Shozo Koyama Yoon Ahm Kim Kenji Takeuchi Naomi Kuroiwa Tamotsu Tsukahara 《Carbon》2009,47(5):1365-503
The longstanding question as to whether carbon nanotubes are intrinsically toxic hinders their widespread industrial application. Here, we clarify the effect of impurities within such tubes through systemic studies of immunological responses in mice by monitoring and examining changes in peripheral T-cell subset and peripheral cytokine levels and histology. Contaminated and clean tubes were subcutaneously implanted in mice. The implanted tubes with impurities clearly induced immunological toxicity and localized alopecia, whereas extremely pure implanted tubes showed good biocompatibility. Our studies suggest that such high-temperature thermal treatment is an effective way to improve the biocompatibility of carbon nanotube. 相似文献
90.
Nishimura S. Inoue H. Matsuoka H. Yokota T. 《IEEE journal of selected topics in quantum electronics》1999,5(2):360-367
Optical interconnection between the nodes of the RWC-1 massively parallel computer has been implemented. A one-node testbed system and an eight-node parallel processing system have been produced to demonstrate large-throughput small-skew low-latency and highly reliable optical internode connection. Each node was interconnected through dc-coupled 24-bit synchronized parallel optical interconnection at 100 MHz using 50-m-long single-mode ribboned fibers. The skew in a 24-bit data signal was suppressed to within 650 to -380 ps, and the OE/EO conversion delay time was 15.2 ns. We ran a parallel-processing program on the eight-node system as an evaluation, and the 50-m-long optically interconnected system performed as well as a 10-m-long electrically interconnected system. This clearly shows that optical interconnection will overcome the communication bottleneck in multinode computer systems 相似文献