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21.
Simple and sensitive normal and reverse flow injection methods for spectrophotometric determination of thiamine hydrochloride (THC) at the microgram level were proposed and optimized. Both methods are based on the reaction between THC and diazotized metoclopramide in alkaline medium. Beer’s law was obeyed over the range of 10–300 and 2–90 μg/mL, the limits of detection were 2.118 and 0.839 μg/mL and the sampling rates were 80 and 95 injections per hour for normal and reverse flow injection methods respectively. The application of both methods to commercially available pharmaceuticals produced acceptable results. The flow system is suitable for application in quality control processes.  相似文献   
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BackgroundChildren who inhabit the same house with tuberculosis (TB) patients are at high risk for infection and illness with TB. Nutritional status (stunting) in children is related to the child's ability to withstand MTB (Mycobacterium Tuberculosis). This study aims to estimated the prevalence of tuberculosis infection and its relationship to stunting in children (under five years) with household contact (HHC) with new TB cases.MethodsA cross-sectional design was implemented. Conducted in July 2018–April 2019 at 13 Public Health Center in Makassar City. The sample size was calculated using one sample situation-about precision formula. Samples were children under five who had contact with new diagnosed TB cases. Tuberculosis infection was measured by TST (tuberculin skin test). Logistic regression with causal model to examine TB infection relationship with stunting and covariate variable, analyzed using Stata/MP 13.0 software.ResultsOne hundred twenty-six (126) eligible children. Prevalence of tuberculosis infection was 38.10%. Frequency of stunted was 31 children (24.60%). Stunted nutritional status (aPR): 2.36, 95% CI 1.60–3.44), boys (aPR: 1.47, 95% CI 0.96–2.25), not getting BCG immunization (aPR: 1.58, 95%) CI 0.89–2.82), and high contact intensity (aPR: 2.62, 95% CI 1.10–6.22) best predicted the tuberculosis infection in children with TB case household contacts with a model contribution of 64%.ConclusionStunted nutritional status (moderate and severe), boys, not getting BCG immunization, and high contact intensity are the determinants of TB infection transmission in children HHC with TB. Children under five years of age who have close contact with TB cases should be targeted for priority interventions to prevent the transmission of TB infection and progressing to TB cases.  相似文献   
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This study was conducted to clarify the role of efflux transporter MRP2 in acetaminophen-induced hepatotoxicity in cats. Sixteen mixed bred male cats and four liver samples from mixed breed male dogs were used. The cats were assigned into four groups (n?=?4), received saline and 2, 10 and 50?mg/kg doses of acetaminophen orally for 14 days. Unlike the intact dogs, the MRP2 was not detectable in control cats. MRP2 at mRNA level was expressed in the liver of cats, which received the medium and high doses. Data suggest that the MRP2 expression may involve in the acetaminophen-induced hepatotoxicity in cats.  相似文献   
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Metabolic Brain Disease - Gaucher disease type 2 is the most progressive and the rarest form of Gaucher disease, defined as the acute neuronopathic type. We presented two GD2 patients who died...  相似文献   
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Background:

Polyethylene glycol (PEG) is often considered as the first-line treatment for functional constipation in children. Descurainia sophia (L.) Webb et Berth (D. sophia) is a safe recommended medicine in Iranian folk and Traditional Persian Medicine for the treatment of constipation.

Objectives:

To clinically compare D. sophia with PEG 4000 (without electrolyte) in pediatric constipation and to assess its efficacy and side effects.

Patients and Methods:

120 patients aged 2 - 12 years with constipation for at least 3 months were included in an 8 weeks lasting randomized controlled trial within two parallel-groups. Children received either PEG, 0.4 g/kg/day, or D. sophia seeds, 2 grams (for children aged 2 - 4 years) and 3 grams (for those aged > 4 years) per day.

Results:

A total of 109 patients completed the study (56 in D. sophia and 53 in PEG group). At the end of the study, 36 (64.3%) patients in D. sophia group and 29 (54.7%) in PEG group were out of Rome III criteria (P = 0.205). Median weekly stool frequency in 0, 1, 2, 3 weeks of the treatment was found to be 2, 5, 5, 5 in D. sophia and 3, 4, 4, 5 in PEG group (P = 0.139, 0.076, 0.844, 0.294), respectively. The number of patients who suffered flatulence was less (5, 8.9%) in D. sophia group as compared to PEG group (6, 11.3%) at the end of the trial (P = 0.461). D. sophia taste was less tolerated.

Conclusions:

D. sophia is introduced as a cheap and available medication which can be applied as a safe alternative to conventional PEG in the management of pediatric chronic functional constipation.  相似文献   
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The current study aims at the development of an electrochemical sensor based on a silver nanoparticle–reduced graphene oxide–polyaniline (AgNPs–rGO–PANI) nanocomposite for the sensitive and selective detection of hydrogen peroxide (H2O2). The nanocomposite was fabricated by simple in situ synthesis of PANI at the surface of rGO sheet which was followed by stirring with AEC biosynthesized AgNPs to form a nanocomposite. The AgNPs, GO, rGO, PANI, rGO–PANI, and AgNPs–rGO–PANI nanocomposite and their interaction were studied by UV-vis, FTIR, XRD, SEM, EDX and XPS analysis. AgNPs–rGO–PANI nanocomposite was loaded (0.5 mg cm−2) on a glassy carbon electrode (GCE) where the active surface area was maintained at 0.2 cm2 for investigation of the electrochemical properties. It was found that AgNPs–rGO–PANI–GCE had high sensitivity towards the reduction of H2O2 than AgNPs–rGO which occurred at −0.4 V vs. SCE due to the presence of PANI (AgNPs have direct electronic interaction with N atom of the PANI backbone) which enhanced the rate of transfer of electron during the electrochemical reduction of H2O2. The calibration plots of H2O2 electrochemical detection was established in the range of 0.01 μM to 1000 μM (R2 = 0.99) with a detection limit of 50 nM, the response time of about 5 s at a signal-to-noise ratio (S/N = 3). The sensitivity was calculated as 14.7 μA mM−1 cm−2 which indicated a significant potential as a non-enzymatic H2O2 sensor.

The current study aims at the development of an electrochemical sensor based on a silver nanoparticle–reduced graphene oxide–polyaniline (AgNPs–rGO–PANI) nanocomposite for the sensitive and selective detection of hydrogen peroxide (H2O2).  相似文献   
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