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Prior to colonoscopy, bowel cleansing is performed for which frequently oral sodium phosphate (OSP) is used. OSP results in significant hyperphosphatemia and cases of acute kidney injury (AKI) referred to as acute phosphate nephropathy (APN; characterized by nephrocalcinosis) are reported after OSP use, which led to a US-FDA warning. To improve the safety profile of OSP, it was evaluated whether the side-effects of OSP could be prevented with intestinal phosphate binders. Hereto a Wistar rat model of APN was developed. OSP administration (2 times 1.2 g phosphate by gavage) with a 12h time interval induced bowel cleansing (severe diarrhea) and significant hyperphosphatemia (21.79 ± 5.07 mg/dl 6h after the second OSP dose versus 8.44 ± 0.97 mg/dl at baseline). Concomitantly, serum PTH levels increased fivefold and FGF-23 levels showed a threefold increase, while serum calcium levels significantly decreased from 11.29 ± 0.53 mg/dl at baseline to 8.68 ± 0.79 mg/dl after OSP. OSP administration induced weaker NaPi-2a staining along the apical proximal tubular membrane. APN was induced: serum creatinine increased (1.5 times baseline) and nephrocalcinosis developed (increased renal calcium and phosphate content and calcium phosphate deposits on Von Kossa stained kidney sections). Intestinal phosphate binding (lanthanum carbonate or aluminum hydroxide) was not able to attenuate the OSP induced side-effects. In conclusion, a clinically relevant rat model of APN was developed. Animals showed increased serum phosphate levels similar to those reported in humans and developed APN. No evidence was found for an improved safety profile of OSP by using intestinal phosphate binders.  相似文献   

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The solubility characteristics of isolated soy protein (ISP) in high ionic environments were measured in accordance with an NSI (nitrogen solubility index) method in order to study the effect of the thermal process in its commercial production. When the acid precipitated protein (APP) dispersions were heated to above 60°C and subsequently spray dried, the solubility of the resultant ISP in 0.5 m (molar) NaCl was lowered with increasing temperature, ranging from 91% at 60°C to 43% at 90°C, while the solubility in H20 remained at almost the 100% level regardless of heating condition. Solubility changes in 90°C-heated ISP in various 0.5m (molal) salt solutions indicated that salting-out of this protein preparation can be represented as a function of molal surface tension increment of the salt used; the solubility of ISP in ionic environments can be determined by its hydrophobicity, which seems to increase with a rise in the heat treatment temperature of APP. Therefore, there was a significant difference in salting-out behavior depending upon the order of addition of ingredients to the system; when salt was added to the slurry after the ISP was thoroughly rehydrated, no salting-out was observed in 0.5m ionic environments. Ultrasonication of 90°C-heated APP prior to spray drying was tested to examine the possibility of improving the solubility profiles of resultant ISP, with the result that a remarkable increase of solubility in 0.5 m NaCl was attained. The effect of such ultrasonication was probably due to its ability to increase the hydrophilic nature of proteins.  相似文献   

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植物响应缺钾胁迫的机制及提高钾利用效率的策略   总被引:4,自引:0,他引:4  
陈光 《植物学报》2017,52(1):89-101
钾是植物体内含量最大的阳离子,在植物生长发育过程的诸多生理生化反应中起关键作用。缺钾会抑制植株根系的生长,使根冠比降低;同时阻碍光合产物的合成和向韧皮部转运,导致生物量下降。因此,提高植物钾营养的吸收转运和利用效率对于作物品种改良和增产具有重要的理论和生产实践意义。该文综述了植物响应低钾的生理机制和提高植物钾利用效率的四大策略,并对改善钾营养吸收利用以提高作物产量和品质进行了讨论及展望。  相似文献   

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目的探讨乙醚吸入与戊巴比妥钠联合麻醉应用效果。方法随机将20只受肝大鼠分成两组,每组10只。A组为单纯的乙醚吸入麻醉对照组,B组先用乙醚吸入作麻醉诱导,再腹腔注射2%戊巴比妥钠作麻醉维持。观察手术时间、术中追加麻醉次数、术后苏醒时间和死亡率。结果与B组相比,A组手术时间明显延长(P〈0.05),术中平均需要重复吸入乙醚5±1.63次,以维持麻醉状态。B组术中麻醉平稳,不需要继续给药.两组术后苏醒时间无显著性差异(P〉0.05)。结论乙醚吸入与戊巴比妥钠联合麻醉,可延长麻醉的有效时间,加强麻醉效果,有效地保证手术的顺利进行。  相似文献   

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Russian Journal of Plant Physiology - The separate foliar application of zinc (Zn) and epibrassinolide (EBL) have widely proved tolerance to several abiotic stresses, but their combined effect...  相似文献   

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The thyroid is one of the major endocrine glands that contribute to body and fat metabolism. The present study evaluated the effects of combined exposure to chronic high-fat diet (HFD) and arsenic on thyroid function and lipid profile. In this experimental study, 72 male Naval Medical Research Institute mice were divided into six groups and fed HFD or low-fat diet (LFD) while being exposed to 25 or 50 ppm of arsenic in drinking water for 20 weeks. After 24 h of the last experimental day, blood samples were collected for hormonal and biochemical measurements. The data indicated that exposure to HFD alone increased the levels of triiodothyronine (T3), thyroid-stimulating hormone (TSH), leptin, lipid profile, reactive oxygen species (ROS), and malondialdehyde (MDA) and decreased the levels of high-density lipoprotein, albumin, adiponectin, and glutathione sulfhydryl reductase (GSH), whereas exposure to arsenic alone decreased the levels of T3 and GSH and increased the levels of TSH, leptin, ROS, MDA, and T4/T3 ratio compared to those in the control LFD group. Furthermore, concomitant administration of HFD and arsenic decreased the lipid profile and levels of T4, albumin, total protein, T3, and GSH and increased the levels of TSH, adiponectin, leptin, ROS, MDA, and T4/T3 ratio compared to those in the control LFD or HFD group. In conclusion, combined exposure to HFD and arsenic induced hypothyroidism via reduction of thyroid hormones and enhancement of plasma TSH and T3 uptake levels concomitant with hypolipidemia, hyperleptinemia, hyperadiponectinemia, induction of oxidative stress, and reduction of GSH levels.  相似文献   

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Sheng  Huajin  Zeng  Jian  Liu  Yang  Wang  Xiaolu  Wang  Yi  Kang  Houyang  Fan  Xing  Sha  Lina  Zhang  Haiqin  Zhou  Yonghong 《Journal of Plant Growth Regulation》2020,39(2):795-808

The effect of Mn and NaCl on growth, mineral nutrients and antioxidative enzymes in two tetroploid wheat genotypes differing in salt tolerance was investigated in this study. 100 mM NaCl and Mn stress significantly inhibited plant growth, photosynthesis and Ca uptake, while stimulated ROS accumulation, MDA and proline content in wheat plants, Mn stress also increased SOD, APX, GR and DHAR activities. Durum wheat (AS780) was less affected by 100 mM NaCl and Mn stress than emmer wheat (AS847) due to more proline production, higher antioxidative enzymes activities and less-affected mineral nutrients. Application of 10 mM NaCl to Mn-stressed durum wheat alleviated Mn-induced damage by reducing Mn accumulation and translocation, while promoting proline accumulation and SOD, APX and GR activities. Irrespective of NaCl level, the combined stress of Mn and NaCl caused more severe oxidative stress, result in further reduction of photosynthetic rate and plant growth in emmer wheat as compared to Mn stress alone. The additively negative effects of NaCl and Mn stress on growth of emmer wheat results from reduced SOD and APX activities as well as Ca, Cu and Fe accumulation in both shoots and roots. These results suggest that salt-tolerant durum wheat is superior to emmer in adapting to Mn stress and the combined stress of salinity and Mn.

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Kylin A  Gee R 《Plant physiology》1970,45(2):169-172
Homogenates from the salt-excreting leaves of the mangrove Avicennia nitida were subjected to differential centrifugation and investigated for adenosine triphosphatase activities. At pH 6.75 a salt stimulation with peaks at three different sodium to potassium ratios could be demonstrated above the activity due to Mg2+ ions. The stimulation by sodium and potassium depends on the ionic strength of the test medium, higher salt concentrations being inhibitory. The plant system seems thus more complicated than the animal activities. Technically, this means that a search for (Na+ + K+)-activated ATPases in plants should be performed with a close spacing of Na:K ratios at several constant levels of salt. Literature data on the transport of Na+ and K+ indicate that the physiological situation is rather complex in plants.  相似文献   

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Defining the aggressiveness and growth rate of a malignant cell population is a key step in the clinical approach to treating tumor disease. The correct grading of breast cancer (BC) is a fundamental part in determining the appropriate treatment. Biological variables can make it difficult to elucidate the mechanisms underlying BC development. To identify potential markers that can be used for BC classification, we analyzed mRNAs expression profiles, gene copy numbers, microRNAs expression and their association with tumor grade in BC microarray-derived datasets. From mRNA expression results, we found that grade 2 BC is most likely a mixture of grade 1 and grade 3 that have been misclassified, being described by the gene signature of either grade 1 or grade 3. We assessed the potential of the new approach of integrating mRNA expression profile, copy number alterations, and microRNA expression levels to select a limited number of genomic BC biomarkers. The combination of mRNA profile analysis and copy number data with microRNA expression levels led to the identification of two gene signatures of 42 and 4 altered genes (FOXM1, KPNA4, H2AFV and DDX19A) respectively, the latter obtained through a meta-analytical procedure. The 42-based gene signature identifies 4 classes of up- or down-regulated microRNAs (17 microRNAs) and of their 17 target mRNA, and the 4-based genes signature identified 4 microRNAs (Hsa-miR-320d, Hsa-miR-139-5p, Hsa-miR-567 and Hsa-let-7c). These results are discussed from a biological point of view with respect to pathological features of BC. Our identified mRNAs and microRNAs were validated as prognostic factors of BC disease progression, and could potentially facilitate the implementation of assays for laboratory validation, due to their reduced number.  相似文献   

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The subject of this study is a spent pot lining (SPL) landfill. The aim of this study was to identify the site remediation option, among four alternatives, that minimizes overall environmental impacts based on: 1) a comparative life cycle assessment (LCA); and 2) modeling of contaminant transport in groundwater. The four options were: leaving the landfill in place (Option 1); excavation of the landfill, with on-site disposal of the excavated materials in a secure cell (Option 2); excavation of the landfill, with treatment of the SPL fraction (Option 3); and excavation of the landfill, with incineration of the SPL fraction in a cement kiln (Option 4). The LCA was performed following the guidelines provided by the International Standard Organization (ISO). Furthermore, to improve the relevance of LCA to site remediation sector, impacts caused by residual in-situ contamination were assessed by applying a simulation of contaminant transport in groundwater, using site-specific data. The LCA identified Option 1 as having the least environmental impacts. However, the transport modeling concluded that contaminant concentrations 50 years from the present could be approximately 30 to 40 times the regulatory criteria if this option is retained. In addition, this study demonstrated that LCA can be used as a screening tool to help identify significant environmental issues; the LCA identified acute and chronic water ecotoxicity categories as being the dominant impact categories of the environmental profile and consequently, it is recommended that a complete environmental risk assessment (ERA) be performed for Option 1.  相似文献   

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Inhibitors of eucaryotes (cycloheximide and amphotericin B) and procaryotes (penicillin and chloramphenicol) were used to estimate bacterivory and bacterial production in a eutrophic lake. Bacterial production appeared to be slightly greater than protozoan grazing in the aerobic waters of Lake Oglethorpe. Use of penicillin and cycloheximide yielded inconsistent results in anaerobic water and in aerobic water when bacterial production was low. Production measured by inhibiting eucaryotes with cycloheximide did not always agree with [3H]thymidine estimates or differential filtration methods. Laboratory experiments showed that several common freshwater protozoans continued to swim and ingest bacterium-size latex beads in the presence of the eucaryote inhibitor. Penicillin also affected grazing rates of some ciliates. We recommend that caution and a corroborating method be used when estimating ecologically important parameters with specific inhibitors.  相似文献   

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Purpose

To estimate the number of venous thromboembolic events and related-premature mortality (including immediate in-hospital lethality) attributable to the use of combined oral contraceptives in women aged 15 to 49 years-old between 2000 and 2011 in France.

Methods

French data on sales of combined oral contraceptives and on contraception behaviours from two national surveys conducted in 2000 and 2010 were combined to estimate the number of exposed women according to contraceptives generation and age. Absolute risk of first time venous thromboembolism in non-users of hormonal contraception and increased risk of thromboembolism in users vs. non-users of hormonal contraception were estimated on the basis of literature data. Finally, immediate in-hospital lethality due to pulmonary embolism and premature mortality due to recurrent venous thromboembolism were estimated from the French national database of hospitalisation and literature data.

Results

In France, more than four million women are daily exposed to combined oral contraceptives. The mean annual number of venous thromboembolic events attributable to their use was 2,529 (778 associated to the use of first- and second-generation contraceptives and 1,751 to the use of third- and fourth-generation contraceptives), corresponding to 20 premature deaths (six with first- and second-generation contraceptives and fourteen with third- and fourth-generation contraceptives), of which there were eight to nine immediate in-hospital deaths. As compared to the use of first- and second-generation contraceptives, exposure to third- and fourth-generation contraceptives led to a mean annual excess of 1,167 venous thromboembolic events and nine premature deaths (including three immediate in-hospital deaths).

Conclusions

Corrective actions should be considered to limit exposure to third- and fourth-generation contraceptives, and thus optimise the benefit-risk ratio of combined oral contraception.  相似文献   

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The survival of plant cells may be tested rapidly and convenientlyby staining tissue sections in a solution of Evan's blue (0·5%w/v) after exposure to solutions of high salt concentrationor low osmotic potential. Living cells retain the ability toexclude Evan's blue at the plasma membrane and remain theirnatural colour. Cells damaged by salt or osmotic stress areunable to exclude Evan's blue, are stained deep blue, and arereadily distinguished upon microscopic examination.  相似文献   

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