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41.
A green extraction method, based on the use of 1,8-cineole (eucalyptol) as biosolvent, has been developed to prepare crude extracts from the brown alga Zonaria tournefortii characterized by chemical composition, particularly dominated by phenolic compounds derived from phloroglucinol. The main advantage of the developed technique are the recovery of eucalyptol, based on multistep liquid-liquid extraction with distilled water, followed by centrifugation and elimination of the aqueous phase, and the complete recycling of biosolvent by steam distillation. A comparative study between the proposed green extract and the conventional extract, prepared by solvent maceration using the mixture CH2Cl2/MeOH (1/1:v/v), was performed in terms of qualitative and quantitative determination of several parameters as:(i) the total phenolic content determined by the Folin-Ciocalteu assay, (ii) the presence of phenols determined by high performance liquid chromatography (HPLC), and (iii) the antioxidant activity assessed by the DPPH (2,2-diphenyl-1-picrylhydrazyl) radical scavenging assay. In short, eucalyptol provides a safe and selective extraction of phenolic compounds from Zonaria tournefortii with no environmental side effects and a good recovery of the solvent.  相似文献   
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So-called “social egg freezing” allows a woman to retain the possibility of trying to have a child with her own oocytes later in life, even after having become infertile in the strict sense of the word (that is, infertile without assistance in reproduction).There is a debate about whether it is morally permissible at all, the extent to which it should be permitted legally or even supported, and whether it is ethically desirable. This paper contributes some thoughts to the issue of ethical desirability. More precisely it deals with the question of whether there is any valuable argument to be made on the basis of the idea of life phases and normative expectations related to them. So the question is: Is there a right time in life to have a child, and does this speak against or in favor of social freezing? This question is answered in three steps. First, I will give an overview of ethical arguments that are mostly put forward in favor or against the use of social egg freezing and show that and why the question of life phases should be taken into account. Second, I will sketch what I understand by phases of life, more precisely, what I understand by normatively conceptualized life stages, that are to be distinguished from other kinds of life phases, and how they relate to a good life. Third, I will present two arguments that rely on the idea of life stages and speak against social egg freezing. However, I will criticize them and instead show that from the perspective of life stages nothing speaks against using the technique within certain limits.  相似文献   
45.
This paper develops and tests a dynamic model of hospital focus. It does so by tracing the performance trajectories of specialist and general hospitals to identify whether a performance gap exists and whether it widens or shrinks over time. Our longitudinal analyses of all hospital organizations within the English National Health Service (NHS) reveal not only a notable performance gap between specialist and general hospitals in particular with regards to patient satisfaction that widens over time, but also the emergence of a gap especially with regards to hospital staff job satisfaction. These findings reflect the considerable potential of specialization as a means to enhance hospital effectiveness. However, they also alert health policy makers to the threat of a widening performance gap between specialist and general hospitals with potential negative repercussions at the patient and health system level.  相似文献   
46.
The quality of aquatic environments all around the world is being altered by different human activities that represent direct threat to the ecological system and the aquatic biota. This study aimed to evaluate the occurrence of histological and genotoxic alterations in Prochilodus lacustris as indicators of anthropic impacts in a lacustrine environment in northeast Brazil. The histological alterations were evaluated using the histological alteration index, and the genotoxic alterations were detected using the micronuclei test, at three sampling stations (S1, S2 and S3). The gills presented lesions with three stages of severity, with mild lesions more frequent in the specimens collected at station S1. Mild hepatic tissue lesions were the most frequent type in both areas. Micronucleus analysis showed that station S3 was the most affected. The biological responses observed indicated that the fish are under influence of environmental changes. It is important to highlight that the organisms collected at station S3 had a more compromised health status.  相似文献   
47.
Disorders of sex development (DSD) are congenital conditions in which the typical genetic and hormonal profiles are affected and thereby the usual process of sexual differentiation. Most of these studies, however, have been conducted in Western countries. In the present study, preschool sex-typed activities of Iranian individuals with DSD and their age-matched non-affected male and female relatives were assessed using the Pre-School Activities Inventory (PSAI) modified for retrospective self-report. A total of 192 individuals participated in our study, including 33 46,XX individuals with congenital adrenal hyperplasia (CAH; M age?=?10.36, SD?=?5.52), 15 46,XY individuals with complete androgen insensitivity syndrome (CAIS; M age?=?19.8, SD?=?7.14), and 16 46,XY individuals with 5-alpha reductase deficiency type-2 (5α-RD-2; M age?=?17.31, SD?=?7.28), as well as one age-matched non-affected male and female relative for each patient. With regard to PSAI scores, male-identifying participants with 5α-RD-2 and male controls reported similar levels of male-typical childhood play. Female-identifying participants with 5α-RD-2 and CAH showed comparable scores: significantly less masculine and more feminine than male controls, but significantly more masculine and less feminine than females with CAIS and female controls. These findings support the role of androgens in the development of sex-typical childhood play behavior, with those being exposed to higher levels of fetal functional androgens expressing more masculine behavior at preschool ages.  相似文献   
48.
The effect of a polyclonal antiserum and OMVU10, a monoclonal antibody reactive with Antigen B of Streptococcus sobrinus , on the interaction of polymorphonuclear leukocytes with S. sobrinus was studied, using chemiluminescence and bacterial killing assays. Increased stimulation of neutrophils as measured in the chemiluminescence assays was established when S. sobrinus was preincubated with polyclonal antiserum or when polyclonal antiserum was added to the reaction mixture. Higher counts were measured in comparison to preimmune serum. After 90 min, 52% of S. sobrinus preincubated with polyclonal antiserum was killed. Killing was also increased when polyclonal antiserum was added to the reaction mixture in comparison to the controls. No killing was found when bacteria were preincubated with OMVU10 or when OMVU10 was added to the reaction mixture in comparison to Clone 24, a control antibody.  相似文献   
49.
Bite-opening procedures are used in the early stages of orthodontic fixed treatment in order to: ease antero-posterior tooth movements; bracket the mandibular arch and level the Curve of Spee; prevent mandibular brackets from debonding; use regular straight archwires to proceed with treatment. For these purposes, removable or bonded biteplanes are universally recognized as very effective when the bite-opening is needed. Conventional orthodontic procedures include clinical solutions which effectively open the bite, but they all lack sufficient hygiene, comfort, and esthetics. The authors propose the use of the CAD-CAM technology with the Cerec 3 system (Sirona, Bensheim, Germany) to create an overcrown able to open the bite through clinical crown lengthening of the mandibular second premolars. The laboratory steps are described and the clinical efficacy is demonstrated with an orthodontic case report.  相似文献   
50.
The CICERO system for CAD/CAM fabrication of full-ceramic crowns   总被引:17,自引:0,他引:17  
The CICERO method of crown fabrication consists of optically digitizing a gypsum die, designing the crown layer buildup, and subsequently pressing, sintering, and milling consecutive layers of a shaded high-strength alumina-based core material, a layer of dentin porcelain, and a final layer of incisal porcelain. Final finishing is performed in the dental laboratory. The CICERO method allows efficient production of all-ceramic restorations without compromising esthetics or function. This article reviews the process involved in the fabrication of a CICERO crown.  相似文献   
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