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21.
The relationships between ascorbic acid (plasma and dietary) and plasma HDL cholesterol (HDL-C), total plasma cholesterol (T-C) and T-C:HDL-C ratio were examined in a population of 235 males and 445 females, age 60-98 years. Many known or suspected determinants of HDL-C and T-C, including age, sex, triceps skinfold thickness, fasting blood glucose, alcohol intake, and others, were considered as covariates due to their potential confounding or modifying effects on the relationships under study. The results show that plasma ascorbic acid is significantly (p less than 0.05) correlated with HDL-C (r = 0.09), T-C:HDL-C (r = 0.10), but not with T-C (r = 0.03). There is a strong age interaction with the largest effect of ascorbic acid in the youngest age group studied (60-69 years). The effects of dietary ascorbic acid are similar but slightly reduced in magnitude.  相似文献   
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A spontaneous lymphoid thymus tumor was discovered in a male Xenopus of the MHC ff genotype. The tumor cell can be transplanted in histocompatible larval ff hosts, but not in ff adults unless irradiated (3000 rad). The tumor is rejected by allogeneic hosts. The tumor cells express neither markers of the B-cell lineage nor MHC encoded molecules; they express only markers of the T-cell lineage. Its lymphoid population is clonal as revealed by the existence of a stable rearrangement pattern of the immunoglobulin genes. Cell lines growing continuously in vitro have been derived from the tumor.  相似文献   
24.
The aim of this study is to improve the dissolution properties of a poorly-soluble active substance, Eflucimibe by associating it with gamma-cyclodextrin. To achieve this objective, a new three-step process based on supercritical fluid technology has been proposed. First, Eflucimibe and cyclodextrin are co-crystallized using an anti-solvent process, dimethylsulfoxide being the solvent and supercritical carbon dioxide being the anti-solvent. Second, the co-crystallized powder is held in a static mode under supercritical conditions for several hours. This is the maturing step. Third, in a final stripping step, supercritical CO(2) is flowed through the matured powder to extract the residual solvent. The coupling of the first two steps brings about a significant synergistic effect to improve the dissolution rate of the drug. The nature of the entity obtained at the end of each step is discussed and some suggestions are made as to what happens in these operations. It is shown the co-crystallization ensures a good dispersion of both compounds and is rather insensitive to the operating parameters tested. The maturing step allows some dissolution-recrystallization to occur thus intensifying the intimate contact between the two compounds. Addition of water is necessary to make maturing effective as this is governed by the transfer properties of the medium. The stripping step allows extraction of the residual solvent but also removes some of the Eflucimibe which is the main drawback of this final stage.  相似文献   
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A four-week assessment of all inpatients who had been prescribed theophylline therapy was carried out at a major Australian teaching hospital. A total of 49 theophylline assays was requested for 36 of 116 patients who were prescribed theophylline. Only 38 (78%) assays were ordered for appropriate indications and at appropriate times. In 26 of the 34 appropriately requested assays that could be followed-up, appropriate action was judged to have been taken on receipt of the assay result. Of the 80 patients who were prescribed theophylline for whom theophylline assays were not ordered, 19 might have benefited from the performance of an assay. It is concluded that the theophylline assay service is not being used optimally.  相似文献   
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The authors describe the different "retentive complexes" proposed by the Akers, Roach and Ney schools and analyse their biomechanical validity.  相似文献   
29.
Due to the sharp increase in liver transplant candidates and the subsequent shortage of suitable donor livers, an extension of the current donor criteria is necessary. Simple cold storage, the current standard in organ preservation has proven to be insufficient to preserve extended criteria donor livers. Therefore a renewed interest grew toward alternative methods for liver preservation, such as hypothermic machine perfusion and normothermic machine perfusion. These “new” preservation methods were primarily assessed in rat models, and only a few clinically relevant large animal models have been described so far. This review will elaborate on these alternative preservation methods. Anat Rec, 291:735–740, 2008. © 2008 Wiley‐Liss, Inc.  相似文献   
30.
Leukocyte extracts, trypsin, and lysozyme are all capable of releasing the bulk of the LPS from S. typhi, S. typhimurium, and E. coli. Bacteria which have been killed by heat, ultraviolet irradiation, or by a variety of metabolic inhibitors and antibiotics which affect protein, DNA, RNA, and cell wall synthesis no longer yield soluble LPS following treatment with the releasing agents. On the other hand, bacteria which are resistant to certain of the antibiotics yield nearly the full amount of soluble LPS following treatment, suggesting that certain heatlabile endogenous metabolic pathways collaborate with the releasing agents in the release of LPS from the bacteria. It is suggested that some of the beneficial effects of antibiotics on infections with gram-negative bacteria may be the prevention of massive release of endotoxin by leukocyte enzymes in inflammatory sites.  相似文献   
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