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991.
J Sánchez A Torres J Serrano J Román C Martín L Pérula F Martínez P Gómez 《Canadian Metallurgical Quarterly》1997,20(5):403-408
BACKGROUND: Locally advanced thyroid cancer invading the tracheal cartilage represents a difficult treatment dilemma during thyroidectomy. METHODS: A retrospective chart review was performed to determine the results of laryngotracheal resection or tracheal cartilage shave with adjuvant radiotherapy in patients with locally advanced thyroid cancer invading the upper airway. RESULTS: Of 597 patients undergoing thyroidectomy for thyroid cancer, 40 were found to have laryngotracheal invasion. Thirty-five patients with superficial invasion underwent cartilage shave procedures with adjuvant radiotherapy; five with full-thickness invasion underwent radical resection, including tracheal sleeve resection (n = 3) or total laryngectomy (n = 2). Histologic subtypes included papillary (n = 32), follicular (n = 2), Hurthle cell (n = 1), medullary (n = 3), and anaplastic (n = 2). Of the cartilage shave group, 25 are currently alive with no evidence of disease at a mean follow-up of 81 months (range 1-290). Six developed isolated local/regional recurrence and were managed with total laryngectomy (n = 1), tracheal resection (n = 1), cervical lymphadenectomy (n = 1), or repeat radiotherapy (n = 3). All six patients remain free of disease at a mean follow-up of 5 years. Of those who underwent initial laryngotracheal resection, four remain free of disease at a mean follow-up of 5 years. The rates of 10-year disease-free survival and overall survival for all patients were 47.9% (95% confidence interval [CI] 24.8, 71.0) and 83.9% (95% CI 70.3, 97.5), respectively. CONCLUSIONS: These data suggest that adequate management of thyroid cancer with laryngotracheal invasion can be achieved with a more conservative surgical approach and adjuvant radiotherapy, reserving more radical resections for extensive primary lesions or locally recurrent disease. 相似文献
992.
A configurable nonlinear filter generator is proposed. The nonlinear function employed is key controllable. By changing the key, a different sequence will be obtained. Simulated results show that an optimal linear complexity profile of the sequence can be generated 相似文献
993.
It is shown that software export is an attainable goal for developing nations, especially when government policies are favorable, and that the industrialized nations dominating the worldwide market can expect some serious competition. Examples of the efforts of developing nations to export software to North America and Europe are cited 相似文献
994.
N Lurie J Slater P McGovern J Ekstrum L Quam K Margolis 《Canadian Metallurgical Quarterly》1993,329(7):478-482
BACKGROUND: Emphasis on ensuring women's access to preventive health services has increased over the past decade. Relatively little attention has been paid to whether the sex of the physician affects the rates of cancer screening among women. We examined differences between male and female physicians in the frequency of screening mammograms and Pap smears among women patients enrolled in a large Midwestern health plan. METHODS: We identified claims for mammography and Pap tests submitted by primary care physicians for 97,962 women, 18 to 75 years of age, who were enrolled in the health plan in 1990. The sex of the physician was manually coded, and the physician's age was obtained from the state licensing board. After identifying a principal physician for each woman, we calculated the frequency of mammography and Pap smears for each physician, using the number of women in his or her practice during 1990 as the denominator. Using unconditional logistic regression, we also calculated the odds ratio of having a Pap smear or mammogram for women patients with female physicians as compared with those with male physicians, controlling for the physician's and the patient's age. RESULTS: Crude rates for Pap smears and mammography were higher for the patients of female than male physicians in most age groups of physicians. The largest differences between female and male physicians were in the rates of Pap smears among the youngest physicians. For the subgroup of women enrolled in the health plan for a year who saw only one physician, after adjustment for the patient's age and the physician's age and specialty, the odds ratio for having a Pap smear was 1.99 (95 percent confidence interval, 1.72 to 2.30) for the patients of female physicians as compared with those of male physicians. For women 40 years old and older, the odds ratio for having a mammogram was 1.41 (95 percent confidence interval, 1.22 to 1.63). For both Pap smears and mammography, the differences between female and male physicians in screening rates were much more pronounced in internal medicine and family practice than in obstetrics and gynecology. CONCLUSIONS: Women are more likely to undergo screening with Pap smears and mammograms if they see female rather than male physicians, particularly if the physician is an internist or family practitioner. 相似文献
995.
Eighty-six children who completed immunization with the two trivalent poliovirus vaccines, live attenuated (OPV) and enhanced potency inactivated (EIPV), in one of four schedules (OPV-OPV-OPV, EIPV-EIPV-EIPV, EIPV-OPV-OPV, and EIPV-EIPV-OPV) at 1 year of age were monitored serologically over the subsequent 4 years and challenged with OPV at 5 years of age. Each of the immunization groups exhibited an initial 10- to 100-fold decline in neutralizing antibody to poliovirus types 1, 2, and 3 during the first 2 years of follow-up; thereafter antibody titers stabilized. The EIPV-EIPV-OPV group maintained the highest antibody levels throughout the observation period, including the response to OPV challenge at 5 years of age. These data suggest that immunization with OPV, EIPV, and combinations of the two vaccines confers long-term immunity. Optimal systemic immunity was associated with two or more doses of EIPV. 相似文献
996.
Beauvais Frederick; Chavez Ernest L.; Oetting Eugene R.; Deffenbacher Jerry L.; Cornell Greg R. 《Canadian Metallurgical Quarterly》1996,43(3):292
Problem-prone behaviors of White American, Mexican American, and American Indian high school dropouts, students in good academic standing, and students in poor academic standing were surveyed. Generally, dropouts were most involved with drugs, perpetration of violence, and victimization by violence, students in poor standing were the next most involved, and students in good standing were least involved. Ethnicity did not interact with academic status, suggesting that differences between dropouts and students were similar across ethnic groups. Some ethnicity and gender main effects were found. Findings were related to R. Jessor's (see record 1992-23064-001) theory of problem-prone behaviors, to peer cluster theory, and to intervention design. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
997.
998.
M Eberstadt B Huang Z Chen RP Meadows SC Ng L Zheng MJ Lenardo SW Fesik 《Canadian Metallurgical Quarterly》1998,392(6679):941-945
When activated, membrane-bound receptors for Fas and tumour-necrosis factor initiate programmed cell death by recruiting the death domain of the adaptor protein FADD to the membrane. FADD then activates caspase 8 (also known as FLICE or MACH) through an interaction between the death-effector domains of FADD and caspase 8. This ultimately leads to the apoptotic response. Death-effector domains and homologous protein modules known as caspase-recruitment domains have been found in several proteins and are important regulators of caspase (FLICE) activity and of apoptosis. Here we describe the solution structure of a soluble, biologically active mutant of the FADD death-effector domain. The structure consists of six antiparallel, amphipathic alpha-helices and resembles the overall fold of the death domains of Fas and p75. Despite this structural similarity, mutations that inhibit protein-protein interactions involving the Fas death domain have no effect when introduced into the FADD death-effector domain. Instead, a hydrophobic region of the FADD death-effector domain that is not present in the death domains is vital for binding to FLICE and for apoptotic activity. 相似文献
999.
The original Smoking Consequences Questionnaire (SCQ; T. H. Brandon & T. B. Baker, 1991) measured college students' outcome expectancies for cigarette smoking. A version (SCQ-Adult) was needed for assessing expectancies in more typical, older, nicotine-dependent smokers. Two separate versions of the SCQ were developed and compared. Tests of construct validity provided greater support for the version comprising probability items over the version comprising subjective expected utility items. As expected, principal components analyses revealed a greater number of factors than the original SCQ suggesting that expectancies become more specific with smoking experience. All scales showed good reliability. Over the course of smoking cessation treatment, expectancies became less positive, especially for abstaining participants. Other validity tests also tended to be consistent with research on alcohol expectancies and with contemporary models of drug outcome expectancies. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
1000.
A. I. Ponomarev V. I. Tsidilkovski K. R. Krylov T. B. Charikova A. A. Lakhtin L. I. Leonyuk 《Journal of Superconductivity and Novel Magnetism》1996,9(1):27-32
The anisotropy of the resistivity and thermoelectric power (TEP)S of Nd1.85Ce0.15CuO4?δ single crystal (T c =17 K) has been investigated. In the temperature rangeT c <T<300 K the ratioρ c/ρab≈104 and the dependencesρ ab (T) andρ c (T) change from quadratic to linear atT~200 K. The dependencesS ab (T) andS c (T) reach a maximum atT>T c and then decrease almost linearly with increasing temperature, changing sign from positive to negative nearT~ 150 K. The features of the resistivity and TEP temperature dependences (the lawρ∝T 2 changing toρ∝T, the change in the sign of S with temperature, and the low TEP anisotropy at largeρ anisotropy) have been interpreted in the framework of the narrow-band model. 相似文献