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31.
The general aspects for the analysis of malalignment of the low tibial region in the three-dimensional space are discussed. Recommendations of clinical and radiological diagnostics prior to low tibial osteotomies are given. Closing wedge, opening wedge, dome-shaped, distraction, rotational and step-shaped osteotomies as well as combined procedures are described. The possibilities of these techniques are pointed out for malalignment after lower leg, pilon and ankle fractures, as well as after trauma of the distal epiphysis of the tibia. Arthroscopy of the ankle is an additional tool for detailed planning of the adequate surgical procedure. The importance of determining an early correction cannot be underestimated.  相似文献   
32.
CN Verheyden 《Canadian Metallurgical Quarterly》1998,101(6):1494-500; discussion 1501-2
Nipple-sparing total mastectomy remains an alternative for management of patients with high risk breast disease or patients with various types of symptomatic breast problems. In a patient with large breasts, however, achieving good cosmesis while still performing a thorough mastectomy remains a challenge. This report includes 10 patients who underwent unilateral nipple-sparing total mastectomy and 10 patients who underwent bilateral nipple-sparing total mastectomy. Tissue expansion was used as the reconstructive technique in this consecutive series done from 1985 through 1988. All expanders were placed in the submuscular position, and hyperbaric oxygen was used when intraoperative fluorescein administration identified marginally perfused areas. The average volume of breast tissue removed was 800 gm. The average permanent implant size was 767 cc. Complications included partial skin or nipple loss, infection, and problems related to the implants themselves. The complication rate, however, was not excessive, and results have been good as measured by cosmetic results, capsule grade, and lack of development of cancer in operated breasts. This reconstructive technique is recommended as an alternative in those patients undergoing nipple-sparing total mastectomy.  相似文献   
33.
A sine wave fitting procedure for characterizing measurements of a periodic signal in the presence of additive noise and an unknown time base distortion is presented. If the time base distortion is modeled by a Fourier series, it suffers from the Gibbs phenomenon (ringing) at the borders of the data record. Usually, this is solved by ignoring data samples at the borders. The latter is unacceptable for very short data records where measuring a sample is (very) expensive and/or (very) time consuming. This paper presents a solution that suppresses the ringing in the estimated time base distortion without ignoring data samples at the borders. The theory is illustrated on simulations and on real vessel density in the wood of a mangrove tree from Kenya (Rhizophora mucronata).  相似文献   
34.
Spaceflight causes changes in the cardiovascular system. These changes contribute to the occurrence of orthostatic intolerance after spaceflight. The study of heart rate variations (HRV) provides a non-invasive means to study the autonomic modulation of heart rate. Non-linear control mechanisms have been suggested to be involved in normal heart rate variations. Non-linear control would be helpful in maintaining healthy cardiovascular values. However, these methods have not yet been used in combination with data after spaceflight. In this study we examined the non-linear response of heart rate to standing before and after spaceflight. Methods: ECG was measured for at least 10 minutes in supine and standing position 30 days before launch; and at 1, 4, 9, and 25 days after return to earth. These measurements were performed in 5 cosmonauts who were in the ISS for 10 days. The Approximate entropy of HRV was calculated. Results: The non-linear stand response was slightly altered immediately after spaceflight but was restored after 25 days. Conclusion: Nonlinear control of heart rate was affected immediately after short duration spaceflight, but not to the extent that the astronauts experienced orthostatic intolerance.  相似文献   
35.
The biological reduction of nitric oxide (NO) in aqueous solutions of FeEDTA is an important key reaction within the BioDeNOx process, a combined physico‐chemical and biological technique for the removal of NOx from industrial flue gasses. To explore the reduction of nitrogen oxide analogues, this study investigated the full denitrification pathway in aqueous FeEDTA solutions, ie the reduction of NO3?, NO2?, NO via N2O to N2 in this unusual medium. This was done in batch experiments at 30 °C with 25 mmol dm?3 FeEDTA solutions (pH 7.2 ± 0.2). Also Ca2+ (2 and 10 mmol dm?3) and Mg2+ (2 mmol dm?3) were added in excess to prevent free, uncomplexed EDTA. Nitrate reduction in aqueous solutions of Fe(III)EDTA is accompanied by the biological reduction of Fe(III) to Fe(II), for which ethanol, methanol and also acetate are suitable electron donors. Fe(II)EDTA can serve as electron donor for the biological reduction of nitrate to nitrite, with the concomitant oxidation of Fe(II)EDTA to Fe(III)EDTA. Moreover, Fe(II)EDTA can also serve as electron donor for the chemical reduction of nitrite to NO, with the concomitant formation of the nitrosyl‐complex Fe(II)EDTA–NO. The reduction of NO in Fe(II)EDTA was found to be catalysed biologically and occurred about three times faster at 55 °C than NO reduction at 30 °C. This study showed that the nitrogen and iron cycles are strongly coupled and that FeEDTA has an electron‐mediating role during the subsequent reduction of nitrate, nitrite, nitric oxide and nitrous oxide to dinitrogen gas. Copyright © 2004 Society of Chemical Industry  相似文献   
36.
The United States' Prospective Payment System has become a blueprint for healthcare cost-savings efforts worldwide. Not without its critics, PPS is now being modified and adopted in an effort to create a universal healthcare system in Europe.  相似文献   
37.
38.
Frameshift mutagens have been detected in the river Meuse downstream of Liège. In most cases, mutagenic activity could only be demonstrated after metabolic activation. The effect was inversely related to river flow. The most important sewage outfalls and industrial discharges in the area were controlled on mutagenic activity. Two effluents, both discharging cokes-oven effluents, were found to contain high quantities of frameshift mutagens. The effluents were split up in neutral, acidic and basic fractions.Only neutral and basic fractions showed mutagenic activity. They were further separated in subfractions by gel chromatography and adsorption chromatography. The mutagenic activity was shown to be present in subfractions containing polynuclear aromatic hydrocarbons and aza-arenes. Mutagenic activity in river water samples could only be located in the polynuclear aromatic hydrocarbon fractions.  相似文献   
39.
Semantic interference and orthographic facilitation are common findings in Stroop-like color and picture-naming tasks. The authors investigated whether these context effects are also obtained when, instead of colors or pictures, definitions are used as target stimuli. In Exp 1, both effects were obtained when definitions of colors such as "the color of tomatoes?" had to be named. This finding was replicated in Exp 2, in which the definitions were taken from a larger set of semantic categories. The remaining 4 experiments showed that the semantic interference effect cannot be attributed to a strategic match or nonmatch decision (Exp 3) and does not show up when the distractor word precedes the definition (Exps 4, 5, and 6). The findings are discussed in relation to accounts of context effects in naming tasks and in relation to word-retrieval problems in the tip-of-the-tongue state. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
40.
Gender differences in keeping secrets from parents in adolescence.   总被引:1,自引:0,他引:1  
The current longitudinal study examined adolescent gender differences in the developmental changes and relational correlates of secrecy from parents. For 4 successive years, starting in the second year of junior high (mean age at Time 1 = 13.2 years, SD = 0.51), 149 male and 160 female Dutch adolescents reported on secrecy from their parents and the quality of the parent–child relationship. Latent growth curve modeling revealed a linear increase in secrecy, which was significantly faster for boys than for girls. Moreover, cross-lagged panel analyses showed clear concurrent and longitudinal linkages between secrecy from parents and poorer parent–child relationship quality in girls. In boys, much less strong linkages were found between poorer relationships and secrecy from parents. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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