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22.
Oat has gained interest due to its high nutritional value. When utilising oat fractions rich in dietary fibre, their inositol phosphate (InsP, including phytate) content is considerably high due to the lack of active phytase in the kilned oat ingredients. The high InsP content is linked to decreased mineral absorption in the gut, but the mineral-binding ability of InsPs also results in antioxidativity and a decrease in starch hydrolysis, thus lowering glycaemic response. This study aimed to further develop an anion exchange liquid chromatographic method for quantification of different InsP forms from oat products and to study the changes in the InsP contents resulting from the differences in the ingredients or processes. The method was applicable for quantifying such InsP forms that can effectively bind minerals. The InsPs were stable at moderate temperatures and in the oat baking process, but a significant degradation occurred during the high-temperature treatments, extrusion, and bacterial fermentation.  相似文献   
23.
Caenorhabditis elegans nematodes (fourth-stage larvae) were exposed for 24 h to long (4 μg/μl) or short (5 μg/μl) double-stranded RNA (dsRNA) of two voltage-gated chloride channel (VGCC) genes, ceclc-1 and ceclc-2, coding for two VGCC proteins, CeClC-1 and CeClC-2. The treatments reduced expression of these genes in F1 progeny in a time- and concentration-dependent manner. Progeny with reduced expression of ceclc-2 (but not ceclc-1) showed significant phenotypic effects, such as increased pharyngeal contractions and decreased locomotion, which were maximal in 48 h old worms. Generally, there was little effect on the worms when expression of ceclc-1 alone was reduced. F1 progeny with reduced expression of both ceclc-1 and ceclc-2 had a higher percentage showing affected locomotion than were present with reduced expression of ceclc-2 alone, whereas the increase in frequency of pharyngeal contractions was not different from that obtained with reduced expression of ceclc-2 alone. These phenotypic effects were consistent with the known expression patterns of ceclc-1 and ceclc-2 in C. elegans tissues. A strong negative correlation was observed between in vitro concentration of long dsRNA and ceclc-2 expression level, as well as between ceclc-2 expression level and corresponding phenotypic effects. The effects of dsRNA exposure are similar to previous studies in which 24-h incubation in 50 ppm of anion transporter (AT) blockers DIDS, 9-AC, IAA-94, or NPPB increased pharyngeal contractions and the proportion of nematodes exhibiting impaired locomotion. These findings confirm that the principal mechanism of nematicidal activity of AT blockers may arise from the inhibition of CeClC-2.  相似文献   
24.
The medical records of 163 neonatal foals that had thoracic radiographs taken within 48 hours of admission to a referral hospital were reviewed. The objectives of this study were (1) to identify risk factors for the development of thoracic radiographic changes and (2) to identify prognostic indicators for survival in foals with radiographic evidence of pulmonary disease. Failure of transfer of passive immunity (IgG concentration < or = 400 mg/dL) was the only risk factor for radiographic evidence of respiratory disease identified by multivariate analysis. Hypoxemic patients (PaO2 < or = 60 mm Hg) were 4.9 times more likely to reveal radiographic abnormalities in a subset of foals for which arterial blood gas results were available. Foals with a serum creatinine concentration > 1.7 mg/dL upon presentation, dyspnea, and a history of dystocia were significantly more likely to die based on the multivariate statistical outcome analysis. An anion gap > or = 20 mEq/dL was strongly associated with nonsurvival in a subset of foals with arterial blood gas results. These hematologic and biochemical variables can be readily obtained during the initial evaluation of sick foals. The presence of a high anion gap appeared to have the greatest clinical impact and may be a useful prognostic indicator in foals with radiographic evidence of respiratory disease. In contrast, the majority of physical examination variables, including evaluation of tachypnea, abnormal respiratory sounds, fever, weakness, and milk reflux from the nares, which are usually obtained during the general respiratory evaluation of foals, were unrelated to outcome.  相似文献   
25.
AIM: To study the effect of the overexpression of p16 on an anion exchange function of band 3 in HeLa cells. METHODS: The expression of p16 and band 3 in HeLa cells was detected by immunohistochemistry (IHC). The p16 cDNA was subcloned to plasmids pEGFP-C1 by PCR and identified by restriction enzyme digestion and sequencing, and then, the recombinant pEGFP-C1-p16 plasmids were transiently transfected into HeLa cells. The expression of fusion protein in HeLa cells was detected by fluorescence microscope. 6-methoxy-N-(3-sulfopropyl)-quinolinium(SPQ)fluorescent probes were used to detect the anion exchange function of band 3. RESULTS: P16 and band 3 were expressed in HeLa cells. The amplificated p16 cDNA sequence was the same as the report sequence. The transfective efficacy of pEGFP-C1-p16 was above 60%. The anion exchange function increased after the transfection of pEGFP-C1-p16 plasmids. CONCLUSION: p16 facilitates the anion exchange function of band 3 in HeLa cells.  相似文献   
26.
竹炭性能的研究进展   总被引:8,自引:0,他引:8  
根据目前国内的竹炭研究进展的状况,综述了竹炭吸附性能、竹炭导电性能、竹炭改良土壤的性能、竹炭的负离子功效和竹炭的远红外功效的研究进展。  相似文献   
27.
不同林分类型对空气质量的影响研究   总被引:10,自引:0,他引:10  
通过对 5种林分中的空气正、负离子进行测定表明 ,不同树种组成的林分 ,空气质量评价指数有明显的区别 :阔叶树组成的林分 ,空气质量最好 ;而松树组成的林分 ,空气质量较差。  相似文献   
28.

Background

The quantitative effect of strong electrolytes, unmeasured strong anions (UAs), pCO 2, and plasma protein concentrations in determining plasma pH can be demonstrated using the physicochemical approach. Plasma anion gap (AG) and strong ion gap (SIG) are used to assess UAs in different species.

Hypotheses

Strong ions are a major factor influencing changes in plasma pH of hospitalized foals. AG and SIG accurately predict severe hyper‐l‐lactatemia ([l‐lac] > 7 mmol/L).

Animals

Seven hundred and ninety three hospitalized foals < 7 days old.

Methods

Retrospective study. The relationship between measured pH and physicochemical variables, and the relationship between plasma [l‐lac] and AG and SIG, were determined using regression analyses. Optimal AG and SIG cut points to predict hyper‐l‐lactatemia were identified using an ROC curve analysis.

Results

Combined, the measured strong ion difference and SIG accounted for 54–69% of the changes in the measured arterial pH of hospitalized foals. AG and SIG were significantly associated with plasma [l‐lac] (P < .0001). The receiver operator characteristics (ROC) AUC of AG and SIG for prediction of severe hyper‐l‐lactatemia were 0.89 (95%CI, 0.8–0.95; P < .0001) and 0.90 (95%CI, 0.81–0.96; P < .0001), respectively. Severe hyper‐l‐lactatemia was best predicted by AG > 27 mmol/L (sensitivity 80%, 95%CI, 56–94, specificity 85%, 95%CI, 73–93; P < .0001) and SIG <−15 mmol/L (sensitivity 90%, 95%CI, 68–98; specificity 80%; 95%CI, 68–90; P < .0001).

Conclusion and clinical relevance

Altered concentrations of strong ions (Na+, K+, Cl) and UAs were the primary cause of acidemia of hospitalized foals. AG and SIG were good predictors of hyper‐l‐lactatemia and could be used as surrogate tests.  相似文献   
29.
Acid-base abnormalities frequently are present in sick dogs. The mechanism for an acid-base disturbance can be determined with the simplified strong ion approach, which requires accurate values for the total concentration of plasma nonvolatile buffers (A(tot)) and the effective dissociation constant for plasma weak acids (K(a)). The aims of this study were to experimentally determine A(tot) and K(a) values for canine plasma. Plasma was harvested from 10 healthy dogs; the concentrations of quantitatively important strong ions (Na+, K+, Ca2+, Mg2+, Cl-, L-lactate) and nonvolatile buffer ions (total protein, albumin, phosphate) were determined; and the plasma was tonometered with CO2 at 37 degrees C. Strong ion difference (SID) was calculated from the measured strong ion concentrations, and nonlinear regression was used to estimate values for A(tot) and K(a), which were validated with data from an in vitro and in vivo study. Mean (+/- SD) values for canine plasma were A(tot) = (17.4 +/- 8.6) mM (equivalent to 0.273 mmol/g of total protein or 0.469 mmol/g of albumin); K(a) = (0.17 +/- 0.11) x 10(-7); pK(a) = 7.77. The calculated SID for normal canine plasma (pH = 7.40; P(CO2) = 37 mm Hg; [total protein] = 64 g/L) was 27 mEq/L. The net protein charge for normal canine plasma was 0.25 mEq/g of total protein or 0.42 mEq/g of albumin. Application of the experimentally determined values for A(tot), K(a), and net protein charge should improve understanding of the mechanism for complex acid-base disturbances in dogs.  相似文献   
30.
Cu^2+·Zn^2+·SDS·DBS对凡纳滨对虾仔虾的毒性试验   总被引:1,自引:0,他引:1  
[目的]研究Cu^2+、Zn^2+和SDS、DBS对凡纳滨对虾仔虾的毒性,为对虾人工育苗用水的水质管理提供参考依据。[方法]用Cu^2+、Zn^2+ 2种重金属离子和十二烷基硫酸钠(SDS)、十二烷基苯磺酸钠(DBS)2种阴离子表面活性剂对720尾凡纳滨对虾仔虾进行96h急性毒性试验。[结果]结果表明,Cu^2+、Zn^2+、SDS、DBS对凡纳滨对虾仔虾的毒性大小依次为Cu^2+〉Zn^2+〉SDS〉DBS;对凡纳滨对虾仔虾的安全浓度分别为0.014、0.028、0.320、0.800ms/L。[结论]Cu^2+、Zn^2+、SDS、DBS对凡纳滨对虾的毒性均随着处理浓度升高、处理时间延长而增强。  相似文献   
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