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1.
Studies related to biomaterials that stimulate the repair of living tissue have increased considerably, improving the quality of many people's lives that require surgery due to traumatic accidents, bone diseases, bone defects, and reconstructions. Among these biomaterials, bioceramics and bioactive glasses (BGs) have proved to be suitable for coating materials, cement, scaffolds, and nanoparticles, once they present good biocompatibility and degradability, able to generate osteoconduction on the surrounding tissue. However, the role of biomaterials in hard tissue engineering is not restricted to a structural replacement or for guiding tissue regeneration. Nowadays, it is expected that biomaterials develop a multifunctional role when implanted, orchestrating the process of tissue regeneration and providing to the body the capacity to heal itself. In this way, the incorporation of specific metal ions in bioceramics and BGs structure, including magnesium, silver, strontium, lithium, copper, iron, zinc, cobalt, and manganese are currently receiving enhanced interest as biomaterials for biomedical applications. When an ion is incorporated into the bioceramic structure, a new category of material is created, which has several unique properties that overcome the disadvantages of primitive material and favors its use in different biomedical applications. The doping can enhance handling properties, angiogenic and osteogenic performance, and antimicrobial activity. Therefore, this review aims to summarize the effect of selected metal ion dopants into bioceramics and silicate-based BGs in bone tissue engineering. Furthermore, new applications for doped bioceramics and BGs are highlighted, including cancer treatment and drug delivery.  相似文献   
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The disposition behavior of trientine, a selective copper-chelating drug for Wilson's disease, and its metabolites in normal patients with Wilson's disease and rats were studied. A high concentration of metabolites appeared in blood samples of patients and rats in the early stage after administration of trientine. Furthermore, large amount of trientine metabolites were excreted into the urine of patients. These results suggest that trientine is remarkably subjected to a first-pass effect. The drug concentration area under the curve (AUC) of the unchanged form and the metabolites of trientine in patients was not dependent on the administered dosage. It seems that the absorption process is an important factor for the disposition behavior of trientine, we have also investigated the uptake characteristics of trientine by rat intestinal brush-border membrane vesicles. The uptake characteristics of trientine were similar to the physiological polyamines, spermine and spermidine. The uptake rate of trientine was dose-dependently inhibited by spermine and spermidine. Moreover, spermine competitively inhibited the uptake of trientine with a Ki value of 18.6 muM. This value is very close to the Km value for spermine (30.4 muM). These data suggested that the uptake mechanism of trientine in rat small intestinal brush-border membrane vesicles was almost identical to that of spermine and spermidine, and that the physiological polyamines seem to have the ability to inhibit the absorption of trientine from the gastrointestinal tract.  相似文献   
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A programming language that considers basic values and classes as objects brings more opportunities of code reuse and it is easier to use than a language that does not support this feature. However, popular statically typed object-oriented languages do not consider classes as first-class objects because this concept is difficult to integrate with static type checking. They also do not consider basic values as objects for sake of efficiency. This article presents the Green language type system which supports classes as classless objects and offers a mechanism to treat basic values as objects. The result is a reasonably simple type system which is statically typed and easy to implement. It simplifies several other language mechanisms and prevents any infinite regression of metaclasses.  相似文献   
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This study examined the effects of O3 and hot water treatments on the epidermis of Golden papaya fruit. Heat treatments were applied in a hot water brushing (HWB) system. Papayas were brushed under a pressurized hot water rinse stage at 45, 55 and 65 °C for 60 s. In the HWB treatment, 4 ppm ozone was applied to the papayas for 1 or 2 min. The results show that ozone applications did not affect the fruit's cuticular surface, while heat treatments allowed natural fissures on the fruit epidermis to recover. Several crystalloid forms were identified on the epidermis of the papayas after the heat treatments. The predominant crystalloid forms on papayas are tubular and there is a positive response to temperature; the higher the temperature, the larger and more frequent the tubular crystalloids.  相似文献   
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The lithium extraction from a lepidolite concentrate using roasting, followed by water leaching, was studied. Several alternative additives were initially tested. The use of sodium and calcium sulfates as additives was evaluated in more detail. The influence of some process variables, namely the roasting time, roasting temperature and the additive/concentrate mass ratio, was studied applying a design of experiments. The lithium extraction was modelled and the fitted and validated model was used to optimize the process response. The increase in the additive/concentrate mass ratio, roasting time and temperature seems to result in solid state reactions and transformations that lead to phase, morphological and particle size distribution modifications, which were assessed by XRPD, SEM, and particle size analyses. In this process, lithium sodium sulfate formation constitutes a crucial step enabling the Li water leaching. High lithium extractions were estimated for several combinations of factors. At 850°C, lithium extractions over 90% are obtained when the roasting time is above 1.90 hour and the additive/concentrate mass ratios are over 0.77. An increase in the temperature to 875°C also leads to lithium extractions over 90% for a roasting time of 1 hour and an additive/concentrate mass ratio of 0.60.  相似文献   
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Dampness is an important degradation issue especially in old buildings and monumental heritage, particularly a rising one as the result of capillary movement of water in the lower sections of walls and other ground-supported structures by capillary action. There are several methods to treat this kind of dampness among which is the wall base hygro-regulated ventilation system an interesting solution for high thick walls with considerable heterogeneity.

A significant number of studies have been undertaken around this method which have been implemented and validated in several heritage buildings. Such achievement has led to the adoption of the HUMIVENT patent system which aims to increase evaporation through peripheral channels on the base of the ventilated walls. A pre-sizing design program was also created and was called HUMIVENT PREDIM.

This study aims to develop a set of auxiliary abacus for pre-sizing wall base ventilation systems. This approach aims to provide fast and expeditious systems sizing in the design and rehabilitation project offices. It allows an easy awareness in the several parameters that influence the wet front and the preliminary ventilation system design. It is a very useful tool for designers allowing them to obtain pre-sizing without extensive knowledge of the program and the associated parameters and with quick understanding of the drying process optimization. For better awareness of the abacus’ potentiality and use, an application example is provided thereof. It is concluded that the abacus can straightforwardly be used for sensitivity studies and for the selection of the best solution in each case.  相似文献   

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Lipogenesis is the process by which fatty acids are synthesized. In metabolic syndrome, an insulin resistant state along with high plasma levels of free fatty acids (FFA) and hyperglycemia may contribute to the lipogenic process. The aim of the present study was to investigate the effects of oral administration of metformin on the expression of lipogenic genes and glycemic profile in mice fed with low‐carbohydrate high‐fat diet by evaluating their metabolic profile. SWISS male mice were divided into 4 groups (N = 7) that were fed with standard (ST), standard plus metformin (ST + MET), low‐carbohydrate high‐fat diet (LCHFD) and low‐carbohydrate high‐fat diet plus metformin (LCHFD + MET) (100 mg kg?1 diet) diets respectively. Food intake, body weight and blood parameters, such as glucose tolerance, insulin sensitivity, glucose, HDL‐c, total cholesterol, triglycerides, ASL and ALT levels were assessed. Histological analyses were performed on hematoxylin and eosin‐stained epididymal adipose tissue histological specimens. The expression levels of peroxisome proliferator‐activated receptor (PPARγ), sterol regulatory element‐binding protein 1 (SREBP1), fatty acid synthase (FAS) and acetyl‐CoA carboxylase (ACC), were assessed by RT‐PCR. This study showed that metformin decreased adipocyte area, body weight and food consumption in obese animals when compared to the standard group. Furthermore, the expression of lipogenic markers in adipose tissue were diminished in obese animals treated with metformin. This data showed that oral administration of metformin improved glucose and lipid metabolic parameters in white adipose tissue by reducing the expression of lipogenesis markers, suggesting an important clinical application of MET in treating obesity‐related diseases in metabolic syndrome.  相似文献   
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