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41.
The present study was designed to explore the mechanism of action of walnut (the seed of Juglans regia) leaf and ridge on hepatic glucose metabolism in diabetic mice. Experimental diabetes was induced by intravenous administration of streptozotocin (60 mg/kg)and confirmed with an increase of blood glucose, 90–100% of the control, 72 hours later. Isolated extracts from walnut leaf and ridges were administered in a single effective dose of 400 mg/kg orally. Firstly, blood glucose was determined every 1 hour until 5 hours post administration of extracts. In the second experiment, the liver was surgically removed, 2 hours post treatment of diabetic animals with extracts, homogenized and used for measurement of key enzymes of glycogenolysis (glycogen phosphorylase, GP) and gluconeogenesis (phosphoenolpyruvate carboxykinase, PEPCK). Treatment by both leaf and ridge extracts decreased blood glucose and liver PEPCK activity and increased blood insulin and liver GP activity. It is concluded that walnut is able to lower blood glucose through inhibition of hepatic gluconeogenesis and secretion of pancreatic insulin.  相似文献   
42.
INTRODUCTION: Constipation is a relatively common problem affecting 15 percent of adults in the Western world, and over half of these cases are related to pelvic floor disorders. This article reviews the clinical presentation and diagnostic approach to posterior pelvic floor disorders, including how to image and treat them. METHODS: A Pubmed search using keywords "rectal prolapse," "rectocele," "perineal hernia," and "anismus" was performed, and bibliographies of the revealed articles were cross-referenced to obtain a representative cross-section of the literature, both investigational studies and reviews, that are currently available on posterior pelvic floor disorders. DISCUSSION: Pelvic floor disorders can occur with or without concomitant physical anatomical defects, and there are a number of imaging modalities available to detect such abnormalities in order to decide on the appropriate course of treatment. Depending on the nature of the disorder, operative or non-operative therapy may be indicated. CONCLUSION: Correctly diagnosing pelvic floor disorders can be complex and challenging, and the various imaging modalities as well as clinical history and exam must be considered together in order to arrive at a diagnosis.  相似文献   
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Understanding and controlling the interaction between the polymer methyldopa (2‐amino‐3‐(3,4‐dihydroxyphenyl)‐2‐methyl‐propanoic acid) (PMDP)–γ‐Fe2O3 nanoparticles and biological fluids is important if the potential of nanoparticles (NPs) in biomedicine is to be realized. Physicochemical studies on the interactions between proteins and NPs are influenced by the surface properties of the NPs. To identify the effects of the NP surface, interactions between human serum albumin (HSA) and PMDP–γ‐Fe2O3 NPs were investigated. Here, the adsorption of HSA onto small (10–30 nm diameter) PMDP–γ‐Fe2O3 NPs was quantitatively analyzed using spectroscopic methods. The fluorescence quenching data were checked for the inner‐filter effect, the main confounding factor in the observed quenching. The binding constants, Ka, were calculated at different temperatures, using a nonlinear fit to the experimental data, and the thermodynamic parameters ?H, ?S and ?G were given. The obtained thermodynamic signature suggests that hydrophobic interactions at least are present. This result indicates that the structure of the protein turns from a structureless denatured state at pH 3 into an ordered biologically active native state on addition of PMDP–γ‐Fe2O3 NPs. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
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In this study, different immersion times were compared for optimization of Chlorophytum borivilianum microtuber production in a RITA (Récipient à Immersion Temporaire Automatique) system. Significantly higher mean number and length of microtubers and growth index were obtained (16, 52 mm and 16, respectively) with 15 min immersion in microtuberization medium (MM) for every 60 min rest period, and could eliminate the occurrence of hyperhydricity. The substitution of MM with liquid hormone-free MS (MSO) medium on week 6 of culture differed significantly in terms of mean number and length of microtubers and growth index compared to earlier substitution at week 3 with MSO but did not differ significantly in comparison to cultures maintained throughout the 9 weeks in MM. Comparison of total saponin of TIS-derived microtubers with tubers of field grown mother plant showed a 1.3-fold increase of saponin (≈21% diosgenin) in the microtubers. The above results hold a promising application of TIS for large scale production of microtubers and accumulated saponin in C. borivilianum.  相似文献   
45.
Haloarchaea (class Halobacteria) live in extremely halophilic conditions and evolved many unique metabolic features, which help them to adapt to their environment. The methylaspartate cycle, an anaplerotic acetate assimilation pathway recently proposed for Haloarcula marismortui, is one of these special adaptations. In this cycle, acetyl-CoA is oxidized to glyoxylate via methylaspartate as a characteristic intermediate. The following glyoxylate condensation with another molecule of acetyl-CoA yields malate, a starting substrate for anabolism. The proposal of the functioning of the cycle was based mainly on in vitro data, leaving several open questions concerning the enzymology involved and the occurrence of the cycle in halophilic archaea. Using gene deletion mutants of H. hispanica, enzyme assays and metabolite analysis, we now close these gaps by unambiguous identification of the genes encoding all characteristic enzymes of the cycle. Based on these results, we were able to perform a solid study of the distribution of the methylaspartate cycle and the alternative acetate assimilation strategy, the glyoxylate cycle, among haloarchaea. We found that both of these cycles are evenly distributed in haloarchaea. Interestingly, 83% of the species using the methylaspartate cycle possess also the genes for polyhydroxyalkanoate biosynthesis, whereas only 34% of the species with the glyoxylate cycle are capable to synthesize this storage compound. This finding suggests that the methylaspartate cycle is shaped for polyhydroxyalkanoate utilization during carbon starvation, whereas the glyoxylate cycle is probably adapted for growth on substrates metabolized via acetyl-CoA.  相似文献   
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N-(Phenethyl)piperazinyl quinolone derivatives that bear a methoxyimino-substituent have been synthesized and evaluated for antimicrobial activity against Gram-positive and Gram-negative microorganisms. In addition, to define structure-activity relationships, ciprofloxacin derivatives containing 2-oxo-2-phenylethyl or 2-hydroxyimino-2-phenylethyl moieties at N-4 position of piperazine ring were prepared and tested. Ciprofloxacin derivatives, containing a N-(chloro-substituted phenethyl) residue, showed in vitro Gram-positive and Gram-negative activity generally comparable or superior to that of reference quinolones.  相似文献   
48.
Biology Bulletin - Background: Nandrolone Decanoate (ND) is one of the most popular androgenic anabolic steroids (AASs) compounds that is widely abused during adolescence. Despite clear evidence...  相似文献   
49.
Traditional and novel approaches to flavivirus vaccines   总被引:9,自引:0,他引:9  
Yellow fever, dengue, Japanese encephalitis and tick-borne encephalitis viruses are the medically most important members of the Flavivirus genus composed primarily of arboviruses. In this paper, we review the commercially available traditional flavivirus vaccines against yellow fever, Japanese encephalitis, and tick-borne encephalitis, as well as modern approaches to flavivirus vaccines. Formalin inactivation technology has been employed to produce killed vaccines. Flaviviruses have been attenuated by multiple passages in animal tissues and cell cultures to produce empirical live attenuated vaccines. The use of traditional methods is being pursued to develop vaccines against other flavivirus diseases, such as dengue, and to improve existing vaccines, such as for Japanese encephalitis. With the recent development of infectious clones, rational approaches to attenuated flavivirus vaccines have employed the introduction of specific mutations into wild type viruses and chimerisation between different viruses. Novel methods for delivery of live vaccines, such as inoculation of infectious DNA or RNA, have been described. Other approaches, such as the construction of protein subunit, expression vector-based and naked DNA vaccines, have been proposed to create alternate vaccine candidates.  相似文献   
50.
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