共查询到20条相似文献，搜索用时 168 毫秒
1.
BackgroundThis study aimed to develop an amplification method of urea detection based on pH-sensitive liposomes.ResultsThe urease covalently immobilized on the magnetic particles and the pH-sensitive liposomes encapsulating ferricyanide were added to the cyclic-voltammeter cell solution where urea was distributed. The conversion of urea into carbonic acid seemed to induce a pH decrease that caused a reduction in the electrostatic repulsion between the headgroups of weakly acidic 1,2-dipalmitoyl-sn-glycero-3-succinate. The reduction induced the liposomes to release potassium ferricyanide that was encapsulated inside. The effects of urea concentration and pH value were investigated. A specific concentration (0.5 mg/mL) of the urea solution was set to observe the response. The activity of urease was reversible with respect to the pH change between 7 and 5. The sensitivity of this detection was almost identical to the comparable techniques such as an enzyme-linked immunosorbent assay and a field-effect transistor.ConclusionsIn summary, the methodology developed in this study was feasible as a portable, rapid, and sensitive method.How to cite: Kang MK, Park J-W. Amplification of urea detection based on pH-sensitive liposomes. Electron J Biotechnol 2021;51. https://doi.org/10.1016/j.ejbt.2021.04.005 相似文献
2.
C. Rekha Srinivasa Phanidhar A. Vidya Sagar A. Revathi W. A. Asra 《Indian journal of clinical biochemistry : IJCB》2007,22(2):136-139
In a prospective study of 47 patients of subclinical hepatic encephalopathy in cirrhosis of liver, aged between 23 and 60
years, 49% showed Helicobacter pylori positivity by rapid urease test. The baseline characters of patients (mean age, serum
creatinine, sereum albumin, serum bilirubin, prothrombin time) were similar among patients with and without Helicobacter infection
in all the patients. There was no statistically significant difference in blood ammonia levels in either group of patients.
Blood ammonia values showed good correlation with the functional state of liver function but they did not show statistically
significant difference between two groups of patients in any of Child Pugh classes. It is concluded that Helicobacter pylori
does not contribute significantly to blood ammonia levels and the severity of hepatic encephalopathy. 相似文献
3.
Serum Urea:Albumin Ratio as a Prognostic Marker in Critical Patients With Non-Chronic Kidney Disease
D. B. Gundpatil B. L. Somani T. K. Saha M. Banerjee 《Indian journal of clinical biochemistry : IJCB》2014,29(1):97-100
Routine laboratory investigations play an important role in estimating the risk of mortality in intensive care unit (ICU) patients. The significance of urea:albumin ratio (UAR) in predicting the stay and mortality of ICU patients is not known. It is a retrospective study of patients admitted to ICU (n = 412) with non-chronic kidney disease (non-CKD). Receiver-operating characteristics (ROC) analysis for predicting mortality was carried out to find area under curve (AUC) and threshold levels. Analysis of survival probability was carried out by Kaplan–Meier method and Log-rank test. The AUC to predict mortality were 0.695, 0.767 and 0.791 for serum albumin, urea and UAR, respectively. The threshold levels for albumin, urea and UAR were 2.8 g/dL, 53 mg/dL, and 23.44 mg/g, respectively. The highest odds ratio (OR) of 9.75 to predict mortality at threshold level was observed for UAR, while OR were 7.0 and 3.62 for serum urea and albumin, respectively. The serum urea above and albumin below threshold level were associated with increase in ICU stay of >3 days but the highest OR of 4.73 to predict stay of >3 days was observed for UAR. Kaplan–Meier survival analysis shows significant (p < 0.001) difference at the threshold value of UAR. Serum urea and albumin are found to be an independent predictor for the mortality and stay; however an increased UAR value is the best parameter in predicting mortality and stay in ICU patients with non-CKD illness. 相似文献
4.
G. Sulochana S. Sethupathy L. Padmanabhan 《Indian journal of clinical biochemistry : IJCB》1989,4(1):36-40
Platelet factor 3 availability time (PF3 AT), Prothrombin time (PT), Plasma phenol, phenolic acids, blood urea and serum creatinine
were estimated in 31 uremic patients. Significant increase (P<0.01) in PF3 AT and plasma phenolic acid was seen in 100 per
cent of cases, while the increase in plasma phenol was seen in 90.3% of cases. The increase in PF3 AT was not uniformly proportional
to the increase in plasma phenol or phenolic acids in all cases. Increase in PF3 AT was significant in cases of uremia with
bleeding diathesis compared to the cases without bleeding diathesis. Increase in PF3 AT after addition of phenol and urea
together to normal platelet rich plasma (PRP) in vitro was greater than the increase in PF3 AT after the addition of phenol
or urea alone. Significant decrease (P<0.01) in PF3 AT, plasma phenol, plasma phenolic acids, blood urea and serum creatinine
was seen in uremic patients after haemodialysis indicating that the retained toxic metabolites which increase PF3 AT are dializable
substances. 相似文献
5.
由于煤气化废水很复杂,废水的排放会带来严重的污染,废水的处理尤为重要,主要介绍废水中酚的回收方法及选择最佳回收方法,溶剂萃取脱酚的优点,溶剂对脱酚效果的影响。甲基异丁基甲酮作为脱酚的萃取剂有其独特的优点,为了验证甲基异丁基甲酮的萃取效果,本试验模拟工艺条件进行了甲基异丁基甲酮的脱酚的具体操作步骤,实验数据的分析及实验结论的综述。 相似文献
6.
发光细菌应用于监测水环境污染的研究 总被引：6，自引：0，他引：6
研究了发光细菌的发光特点,发现其发光强度随着细菌密度的增加而增加,两者表现为明显的线性关系,水环境中的汞、苯酚都抑制发光细菌的发光,且发光抑制程度与汞、苯酚的浓度之间存在着显著的相关关系．在此基础上,将建立的发光细菌发光检测技术初步应用于监测京杭运河的水污染． 相似文献
7.
Samuel M. Burka 《Journal of The Franklin Institute》1920,189(1):25-46
Since ammonia, when added to the dye bath in preparing bathed plates, increases the sensitizing action of the dye, its action on commercial plates was investigated.In the course of the work three methods of sensitometry were used. Of these, one was used as a first qualitative test; the second, the spectrograph method, was used to study the effect of the ammonia on the sensitivity of the plate to each wave-length; the third, the Hurter and Driffield method, gives the absolute value of the speed of the plate.It was found that by bathing commercial panchromatic plates in a solution of 25 c.c. ethyl-alcohol, 75 c.c. water, and 3 c.c. of strong ammonia water (20 per cent. NH3) for four minutes at 18° C. and drying rapidly, the speed to white light is increased 100 per cent. in nearly all cases, and the sensitivity in the red. extended one hundred or more Ångström units. The speed in the red is increased, in many cases, 400 per cent. If the plates be bathed without the alcohol (100 c.c. water, c.c. ammonia water) the speed is still more increased, but the plates should be used immediately after drying.Ordinary plates do not have their sensitivity appreciably changed. Most brands of orthochromatic plates are not improved, although one, the Cramer Trichromatic, showed the same increase as the panchromatic plate. 相似文献
8.
主要采用纳米TiO2悬浮体系在中压汞灯照射下光催化氧化处理苯酚废水,利用756MC型紫外可见分光光度计测定苯酚溶液在270nm处的吸光度.考察了pH值、纳米TiO2的投加量、苯酚溶液的初始浓度以及处理时间对苯酚去除率的影响.结果表明:在本实验所设定的中压汞灯照射下,pH值为3,纳米TiO2的用量为40mg.L-1,苯酚的初始浓度为10 mg.L-1,恒温磁力搅拌器搅拌的条件下,反应1h,去除率达69.01%.本实验是从理论和经济角度综合考虑,得出了以上最佳处理条件. 相似文献
9.
Fouzia Rashid M. Kaleem Sheema B. Bano 《Indian journal of clinical biochemistry : IJCB》2005,20(1):109-114
The present study is related to the comparative effects of fish oil and olive oil supplementation on gentamicin induced nephrotoxicity
in rats. Three treatment groups (Pretrement, Co-treatment and post treatment) were chosen for the study. Nephrotoxicity in
rats was induced by intraperitonial administration of gentamicin (80 mg/kg/d) for 3,5,7,10,& 12 consecutive days. The animals
were sacrificed 12 hrs after last treatment in each group. The maximum nephrotoxicity was developed on 10 days treatment of
gentamicin. For each group a control group was taken without any oil or gentamicin treatment. Beneficial effects of oils were
evidenced by reduced serum urea and creatinine concentrations in the group receiving oils compared to the non oil treatment
animals receiving gentamicin only. Further, the changed values of alkaline phosphatase and acid phosphatase activity retumed
to normal in kidney and liver tissue homogenates after fish and olive oil treatment. In this study, it was found that co-treatment
of fish and olive oil is more effective antagonist of gentamicin induced nephrotoxicity. However fish oil was found to be
more effective. Hypercholesteromia associated with gentamicin induced nephrotoxicity is also lowered by oil supplementations.
The beneficial effects of these oils are due to counteracting effect of the biochemical alterations induced by the drug. 相似文献
10.
4-氯-2,6-双吡啶双氧钒化合物降低1型糖尿病大鼠血糖的生物学作用 总被引：1，自引：0，他引：1
通过1型和2型糖尿病动物模型的研究发现过渡金属元素钒（V）具有降糖作用。有机钒化合物与无机钒相比，其副作用低、体内吸收率和生物利用度高。本文主要探讨了四价有机钒化合物4-氯-2,6-双吡啶双氧钒化合物（4-chloro-2,6-dipicolinatodioxovanadium(Ⅳ)，V4dipic-Cl）对链脲佐菌素（STZ，55 mg/kg）诱导的1型糖尿病大鼠的生物学作用。大鼠通过自由饮水的方式口服V4dipic-Cl（0.5 mg/ml）8天。结果表明，V4dipic-Cl组的大鼠血糖和血清碱性磷酸酶（ALP）活性显著低于糖尿病对照组，并且其葡萄糖耐量水平得到明显改善。但有机配体H2dipic-Cl对糖尿病大鼠的血糖和血清ALP活性的影响不显著。结果提示V4dipic-Cl具有降低糖尿病大鼠的血糖，提高葡萄糖耐量和改善肝功能的作用。 相似文献
11.
介绍了skalar流动分析测试水中氨氮的技术原理,通过精密度、准确度以及和国标方法的比对实验,建立了间隔式流动分析测定氨氮含量的方法。经测试,方法检测限为0．03mg／L,用于黄河水样测定,结果令人满意。 相似文献
12.
Fructose developed a pinkish orange chromogen on treatment with o-cresol: 70% sulphuric acid at 32°C for 15 minutes with a
λ max of 500nm. Fructose was 185 times more chromogenic than glucose. Total carbohydrate and fructose values in protein-free
filtrate of normal serum samples were in the range, 55.4–86.3 mg/dl and 1.55–3.29 mg/dl, respectively. In diabetes, the observed
values were 197–354 mg/dl and 2.91–6.81 mg/dl, respectively. 相似文献
13.
Merin Iype Subramanya Upadhya Sharmila Upadhya Gopalakrishna Bhat 《Indian journal of clinical biochemistry : IJCB》2008,23(4):401-403
Experimental model of chronic renal failure in rats have been described by many authors and has also been widely used in various
studies. Many of these methods used highly sophisticated instruments which was difficult in our settings. The resection model
was ideal in our experimental set-up, but this model had the risk of excessive bleeding and hypovolemia. In our study we used
a combination of partial resection and ligation of the renal artery to create two models of stable uremia A and Moderate uremia
B. Severe uremia. Both these models were compared with a sham operated group which served as controls. Following surgical
procedure, the development of uremia was monitored by serial estimation of blood urea and serum creatinine levels that were
measured at regular intervals (bi-weekly). From two weeks onwards the animals in the experimental group showed a significant
elevation in the serum urea levels and a consistent elevation in the serum creatinine levels upto eight weeks when compared
to the animals in the sham operated group. We established a modified method of producing renal failure which can be maintained
for a period of six weeks. This model is simple, reproducible and less complicated that can be used for several studies relating
to renal failure in the field of research. 相似文献
14.
Rachna Agarwal Sangeeta Sharma Neelam Chhillar Kiran Bala Neeraj Singh C. B. Tripathi 《Indian journal of clinical biochemistry : IJCB》2009,24(4):366-369
The present study was conducted to assess correlation of ammonia levels with valproate levels in epileptic patients presenting
with valproate toxicity and also whether liver enzymes and ammonia levels could serve as biochemical marker of valproate toxicity.
100 patients with epilepsy who had received valproate therapy for more than 12 months and had presented with valproate toxicity
and 100 controls were included in the study. The serum valproate, ammonia and liver enzymes were measured in these subjects.
In patients with valproate toxicity, the mean level of serum valproate was 110.91 ± 28.68 mg/dL (therapeutic range 50–100
mg/dL). Serum ammonia was higher (86.37 ± 39.90 μg/dL) in patients with valproate toxicity compared to controls (68.73 ± 30.07
μg/dL). Out of 100 patients, only 37 patients had serum valproate level > 120 mg/dL and 22 patients had raised levels of valproate
as well as ammonia. Age < 30 years and serum ammonia > 69 μg/dL is risk factors for valproate toxicity. Serum ammonia, liver
enzymes should be regularly investigated in patients on valproate therapy for early diagnosis of valproate toxicity. 相似文献
15.
根据测量不确定度评定与表示理论,采用纳氏试剂分光光度法测定水中氨氨的测量不确定度,通过计算和评定,得出该法测定水是氨氮的测量结果2．88mg／l时,取包含因子k=2（约95％置信概率）,扩展不确定度u=0．092mg／l。该不确定度评价方法在实际工作中具有较强的实用价值。 相似文献
16.
千烟洲红壤丘陵水资源合理开发利用途径 总被引：1，自引：0，他引：1
千烟洲红壤丘陵水资源合理开发利用途径是以小型塘坝为主，拦蓄地表径流，发展生态立体农业，定点试验获得成功。经济、生态、社会效益都很好，科研成果已推广到上面，同时又提出了进一步搞好试区水利建设的意见，点面结合，使科研成果不断转化成生产力。 相似文献
17.
催化剂对亚临界水中生物质液化行为的影响 总被引：1，自引：0，他引：1
随着社会经济的发展,人类对燃料的需求量越来越大,所以近年来生物质在亚临界水中的液化反应越来越多的得到国内外科研人员的关注,以求得到石油的替代品——生物油。结合我国废生物质利用的现状,本研究用稻草为原料,以得到高产量高品质的生物油为目的,使用间歇式高温高压反应釜,在反应温度573K,压力18MPa．停留时间5min的条件下,对稻草在加入不同催化剂条件下的反应进行实验研究。实验结果表明加入适量的催化剂ZnCl2可以使生物油的产率显著增加,最高可达到32．90％,加入适量的催化剂Na2S可以使生物油的热值（HHV）显著升高,最高可达34．05MJ／kg.当两种催化剂同时加入时可以使生物油的产率和热值同时达到最大,并且使反应剩余残渣减少,并对生成的生物油进行了观察和分析。同时使用GC—MS（气相色谱一质谱联用）技术对生物油的成分进行了定性、定量分析,进一步确定了生物油的成分以及含量。 相似文献
18.
Pradeep Naik B. Premsagar M. Mallikarjuna 《Indian journal of clinical biochemistry : IJCB》2015,30(1):94-98
The acute renal failure is the frequent medical complication observed in liver transplant patients. The objective of this study was to determine the cause of acute renal failure in post liver transplant patients. A total of 70 patients who underwent (cadaveric 52, live 18) liver transplantation were categorized based on clinical presentation into two groups, namely hepatorenal failure (HRF, n = 29), and Hepatic failure (HF, n = 41). All the patients after the liver transplant had received tacrolimus, mycophenolate and steroids. We analyzed the modification of diet in renal disease, (MDRD) serum urea, creatinine and albumin before and after 5th and 30th day of liver transplant and data was categorized into survivors and non-survivors group. In HRF survivor group, serum creatinine, and urea levels were high and, albumin, MDRD were low in pre- transplant and reached to normal levels on 30th day of post transplant, and 79.3 % of patients in this group showed resumption of normal kidney function. On the contrary in HRF nonsurvivor group, we did not observed any significant difference and 20.7 % of patients showed irreversible changes after the liver transplant. In HF survivor group, 82.9 % of liver failure patients did not show any deviation in serum creatinine, urea, albumin and MDRD, whereas in HF non survivor group, 17.1 % of liver failure patients who had HCV positive before the transplant developed acute renal failure. The levels of creatinine, urea, albumin and MDRD were normal before the transplant and on day 30th, the levels of albumin and MDRD were significantly low whereas serum urea, creatinine levels were high. In conclusion, based on these observations, an diagnosis and treatment of Acute renal failure is important among the liver transplantation cases in the early postoperative period. 相似文献
19.
基于GIS的红壤丘陵区脆弱生态系统土壤侵蚀研究——以长沙市为例 总被引：1，自引：1，他引：1
中国南方红壤丘陵区是非常脆弱的生态系统之一，红色荒漠化现象非常严重。本研究以红壤丘陵区典型区域——长沙市为例，首先探讨了SEIM(Soil Erosion Index Model)模型的基本结构以及相对应的各个参数的取值；然后在地理信息系统的支持下，利用SEIM模型，研究了红壤丘陵区的水土流失现状特征及动态变化，并对产生变化的原因进行了初步探讨。研究结果表明，SEIM模型的预测结果基本上能够反映红壤丘陵区土壤侵蚀现状的总体趋势；而红壤丘陵区水土流失现状研究表明，红壤丘陵区总体的水土流失量较小，轻度和微度侵蚀面积达到95%以上，中度以上侵蚀范围不到5%。红壤丘陵区的动态分析结果表明，从1986年到2000年，红壤丘陵区土壤侵蚀程度总体上来讲在逐步减弱，而局部地方，由于人类活动导致的土地利用方式的不合理，土壤侵蚀比较严重。 相似文献
20.
In this article, the authors present the fabrication of an enzyme-entrapped alginate hollow fiber using a microfluidic device. Further use of enzyme-entrapped alginate hollow fibers as a biocatalytic microchemical reactor for chemical synthesis is also deliberated in this article. To ensure that there is no enzyme leaching from the fiber, fiber surfaces were coated with chitosan. To confine the mobility of reactants and products within the porous hollow fibers the entire fibers were embedded into a transparent polydimethylsiloxane (PDMS) matrix which also works as a support matrix. A vanadium-containing bromoperoxidase enzyme isolated from Corallina confusa was used as a model enzyme to demonstrate the use of these alginate hollow-fiber reactors in bromo-oxidation of phenol red to bromophenol blue at different dye flow rates. Stability of the entrapped enzyme at different temperatures and the effect of the chitosan coating on the reaction conversion were also studied. It was observed that molecules as big as 27 kDa can be retained in the matrix after coating with chitosan while molecules with molecular-weight of around 378 Da can still diffuse in and out of the matrix. The kinetic conversion rate in this microfluidic bioreactor was more than 41-fold faster when compared with the standard test-tube procedure. 相似文献