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1.
W. Shieh R. Hui X. Yi 《Photonics Technology Letters, IEEE》2006,18(10):1122-1124
We perform a systematic measurement of the degree-of-polarization (DOP) and eye-closure penalty for optical signals with orthogonal polarizations. We find that the symmetry of DOP is maintained for the orthogonal polarizations under both first and higher order polarization-mode dispersion (PMD), whereas the symmetry of eye-closure penalty is broken under second-order PMD. An orthogonal polarization pair can have large disparity of eye-closure penalty despite an identical DOP. We also demonstrate a novel approach to estimate the maximum eye-closure penalty asymmetry with three orthogonal polarizations on the Poincare/spl acute/ sphere. 相似文献
2.
OBJECTIVE: To examine the relationship between pregnancy incidence and the level of serum E2 during danazol therapy. DESIGN: Danazol was given by 200 mg four times daily for 3 months. Serum E2 level was checked after completing the therapy, but before stopping medication. Patients then were advised to conceive at the appropriate time over a 6-month period. SETTING: Reproductive and Endocrine Laboratory of the Department of Obstetrics and Gynecology, Keelung Chang Gung Memorial Hospital, Keelung, Taiwan. PATIENTS: Infertile women with invasive endometriosis receiving conservative surgery and danazol treatment. INTERVENTIONS: Serum E2 is checked before medication and at the end of danazol therapy, but before stopping medication. MAIN OUTCOME MEASURES: Whether pregnancy is related to the change of serum E2 caused by danazol therapy. RESULTS: There were 24 pregnancies in 38 patients with invasive endometriosis after treatment. Pregnant patients had significantly lower serum E2 levels as compared with the nonpregnant patients. CONCLUSIONS: After conservative surgery for invasive endometriosis associated with infertility, the therapeutic period of danazol treatment could be shortened to 3 months. Because there is significant correlation of fecundability and serum E2 after danazol medication, serum E2 could be a guideline for predicting pregnancy or for prolonging or changing of treatment after danazol therapy. 相似文献
3.
台北101层国际金融中心之结构施工技术与其设计考量概述 总被引:1,自引:0,他引:1
本文旨在简要说明目前正在施工中之超高层大楼—台北国际金融中心之结构系统、钢结构工程、钢筋混凝土工程基础与深开挖工程等特殊施工技术,并佐以相关之设计考量与施工规划概要,以供工程界做参考。 相似文献
4.
DC Reynolds CE Leak KK Bajaj CE Stutz RL Jones KR Evans PW Yu WM Theis 《Canadian Metallurgical Quarterly》1989,40(9):6210-6217
5.
The perception and discrimination of rapidly changing texture stimuli by pigeons was examined in a target localization task. Five experienced pigeons were rewarded for finding and pecking at a randomly placed odd target block of small repeated elements embedded in a larger rectangular array of contrasting distractor elements. On dynamic color test trials, the color of the target, distractor, or both of these regions changed at rates of 100, 250, 500, or 1000 ms per frame. The number of colors appearing within such trials also varied. Pigeons performed well above chance in all test conditions, with target-associated changes producing the best discrimination. The results suggest: (a) global relational information can exclusively guide target localization behavior, (b) pigeons can perceptually group and segregate colored textured differences quite rapidly (< or = 100 ms), and (c) pigeons may possess automatic search control processes that can be captured by stimulus-driven changes in the display. 相似文献
6.
V Douzdjian SS Bhaskar PK Baliga KK Gugliuzza PR Rajagopalan 《Canadian Metallurgical Quarterly》1997,20(8):1310-1314
OBJECTIVE: The racial impact on graft outcome is not well defined in diabetic recipients. The purpose of this study is to analyze our experience with kidney-alone (A) and kidney-pancreas (KP) transplantation in type 1 diabetic recipients and evaluate the impact of racial disparity on outcome. RESEARCH DESIGN AND METHODS: The records of 217 kidney transplants (118 KA, 99 KP) performed on type 1 diabetic patients between 1985 and 1995 at the Medical University of South Carolina and the University of Texas Medical Branch were reviewed. RESULTS: A total of 53 (31%) white patients and 15 (33%) black patients experienced at least one episode of biopsy-proven acute rejection of the renal graft (NS). Patient survival at 1, 2, and 5 years was similar in white (92, 87, 69%) and black (91, 91, 69%) patients (NS). Kidney graft survival at 1, 2, and 5 years in the KA group was 72, 62, and 42% in blacks, compared with 79, 76, and 53% in whites (NS). Kidney graft survival at 1, 2, and 5 years in the KP group was 92, 92, and 74% in blacks, compared with 83, 77, and 58% in whites (NS). Pancreas graft survival at 1, 2, and 5 years was 81, 81, and 81% in blacks, compared with 81, 75, and 62% in whites (NS). Cox regression analysis revealed that donor age > or = 40 years increased the risk of renal graft failure 6.2-fold (P = 0.0001), whereas the addition of a pancreas transplant to a kidney and a living-related transplant decreased the risk of failure of the kidney graft 0.2 (P = 0.005) and 0.1 times (P = 0.005). CONCLUSIONS: Our results suggest that when compared with whites, there may be a trend toward an improved kidney and pancreas graft outcome in blacks undergoing KP transplants. These findings suggest that diabetes may override the risk factors that account for the pronounced disparity in outcome observed between nondiabetic white and black recipients. 相似文献
7.
H Lee KB Idler P Swanson JJ Aparicio KK Chin JP Lax M Nguyen T Mann G Leckie A Zanetti 《Canadian Metallurgical Quarterly》1993,196(1):57-69
Seven cardiac electrophysiology stimulators from four manufacturers (Biotronik, Bloom, Digitimer and Medtronic) in common current use are reviewed. The stimulators differ in the features provided and the design adopted to achieve these features. The number of output channels ranges from one to four, the number of extra-stimuli available ranges from two to six, and these can be delivered as a variety of sequences. Some of the stimulators (Digitimer and Bloom) are modular while others (Biotronik and Medtronic 532 series) are of an integrated design comprising a single physical unit. The design of the Medtronic EP-2 has both integrated and modular characteristics. The features of the stimulators associated with input, output, control and the user interface are specifically reviewed. The features are also compared against the published recommendations of the American Heart Association. In addition, a summary of stimulator user comments from a number of electrophysiology centres is presented. All of the stimulators fulfil, or are close to fulfilling, basic electrophysiological requirements, but some provide more complex facilities such as would be required by specialist centres. 相似文献
8.
PJ Colletier AS Garden WH Morrison H Goepfert F Geara KK Ang 《Canadian Metallurgical Quarterly》1998,20(8):674-681
BACKGROUND: This retrospective study assesses the outcomes and patterns of failure in patients with squamous cell carcinoma metastatic to cervical lymph nodes from an unknown primary site treated with combined surgery and postoperative radiotherapy. METHODS: One hundred thirty-six patients with squamous cell carcinoma metastatic to cervical lymph nodes from an unknown primary source were treated postoperatively with radiotherapy at the University of Texas M. D. Anderson Cancer Center between the years 1968 and 1992. Stage distribution was: N1, 31 patients; N2a, 49; N2b, 25; N2c, 3; N3, 18; and Nx, 10. Thirty-nine patients had excisional biopsies only, 64 patients underwent modified neck dissections, and 33 had radical neck dissections. Extracapsular extension was present in 87 cases. Fifty-nine patients had multiple nodes involved. The median duration of follow-up for surviving patients was 8.7 years. RESULTS: Twelve patients, all with extracapsular nodal disease, developed regional relapse. The 5-year actuarial rates of regional relapse in patients with and without extracapsular nodal disease were 16% and 0%, respectively (p = .004). Nine patients (22%) with extracapsular disease and multiple nodes relapsed compared with three patients (7%) with extracapsular disease and a solitary node (p = .02). None of the patients treated with excisional biopsy and radiotherapy relapsed regionally. No statistically significant relationship between dose, treatment duration, time interval between surgery, and the start of radiotherapy and relapse was detected. The 2-, 5-, and 10-year actuarial disease-specific survival rates were 82%, 74%, and 68%, respectively. Fourteen patients developed cancers in head and neck mucosal sites; six of these cancers were located in unirradiated tissues. CONCLUSIONS: Relapse occurred infrequently in patients treated with excisional biopsies and postoperative radiotherapy. Extracapsular extension and multiple nodes were associated with worse regional control and disease-specific survival. These results appear consistent with those expected for patients with advanced neck disease and a known primary site, and the absence of a primary site should not exclude patients from studies aiming to improve outcomes in patients with extensive neck disease from a head and neck squamous cell cancer. We continue to recommend radiation to the necks and pharyngeal axis for patients suspected of having residual microscopic disease following surgery for squamous cell carcinoma metastatic to the neck from an unknown primary site. 相似文献
9.
BH Shieh MY Zhu JK Lee IM Kelly F Bahiraei 《Canadian Metallurgical Quarterly》1997,94(23):12682-12687
Visual transduction in Drosophila is a G protein-coupled phospholipase C-mediated process that leads to depolarization via activation of the transient receptor potential (TRP) calcium channel. Inactivation-no-afterpotential D (INAD) is an adaptor protein containing PDZ domains known to interact with TRP. Immunoprecipitation studies indicate that INAD also binds to eye-specific protein kinase C and the phospholipase C, no-receptor-potential A (NORPA). By overlay assay and site-directed mutagenesis we have defined the essential elements of the NORPA-INAD association and identified three critical residues in the C-terminal tail of NORPA that are required for the interaction. These residues, Phe-Cys-Ala, constitute a novel binding motif distinct from the sequences recognized by the PDZ domain in INAD. To evaluate the functional significance of the INAD-NORPA association in vivo, we generated transgenic flies expressing a modified NORPA, NORPAC1094S, that lacks the INAD interaction. The transgenic animals display a unique electroretinogram phenotype characterized by slow activation and prolonged deactivation. Double mutant analysis suggests a possible inaccessibility of eye-specific protein kinase C to NORPAC1094S, undermining the observed defective deactivation, and that delayed activation may similarly result from NORPAC1094S being unable to localize in close proximity to the TRP channel. We conclude that INAD acts as a scaffold protein that facilitates NORPA-TRP interactions required for gating of the TRP channel in photoreceptor cells. 相似文献
10.
KK Lyngberg M Harreby H Bentzen B Frost B Danneskiold-Sams?e 《Canadian Metallurgical Quarterly》1994,75(11):1189-1195
The effects of physical training on elderly, fragile patients with rheumatoid arthritis (RA) who are on low-dose steroids were investigated. The controlled study included 24 patients who had been treated with low-dose steroids for 2 years. Each patient was assigned either to a treatment group receiving training or to an untrained control group. The training took place over a 3-month period and was based on a protocol using progressive interval training consisting of bicycle exercises, heel lifts, and step-climbing. The exercises were performed twice weekly for 45 minutes. Comparison of the two groups showed that disease activity did not increase in the trained group and that fewer, but not significantly fewer, swollen joints were observed in this group (p = 0.06). No significant changes were noticed in erythrocyte sedimentation rate, tender joints, or morning stiffness. The work capacity of the trained patients were doubled and the numbers of repetitions increased 76%. Individually adapted exercise programs can therefore be recommended for elderly rheumatoid arthritis patients on steroid treatment. 相似文献