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81.
Ana Carolina Vieira Costa Fernandes Távora Antonieta B Castro Maria Afonsina M Milit?o José Eduilton Gir?o Karina de Cássia Braga Ribeiro Lara Gurgel Fernandes Távora 《The Brazilian journal of infectious diseases》2008,12(1):75-79
This study was designed to describe the epidemiology and risk factors for nosocomial infection (NI) in a Brazilian neonatal intensive care unit (NICU). This study was a retrospective cohort from January to December, 2003. All neonates admitted to the NICU. Infection surveillance was conducted according to the NNIS, CDC. Chi-square test and logistic regression model were performed for statistical analyses. The study was conducted at a public, tertiary referral NICU of a teaching hospital in the Northeast of Brazil. A total of 948 medical records were reviewed. Overall NI incidence rate was 34%. The main neonatal NI was bloodstream infection (68.1%), with clinical sepsis accounting for 47.2%, and pneumonia was the second most common NI (8.6%). Multivariate analysis identified seven independent risk factors for NIs: birth weight, exposure to parenteral nutrition, percutaneous catheter, central venous catheter or mechanical ventilation, abruptio placentae and mother's sexually transmitted disease (STD). Neonates from mothers with STD or abruptio placentae, those weighing less than 1,500 g at birth or those who used invasive devices were at increased risk for acquiring NI. 相似文献
82.
Sanmoy Karmakar Sreerupa Biswas Rammohan Bera Samiran Mondal Amit Kundu Md Asif Ali Tuhinadri Sen 《Yao wu shi pin fen xi = Journal of food and drug analysis.》2015,23(2):327
The present study was undertaken to investigate the food–drug interaction of carbamazepine (CBZ). Common fruit juices [grapefruit juice (GFJ), lime juice (LJ)], known to inhibit the enzyme cytochrome P450 3A4 (CYP3A4), and some widely consumed beverages [milk (M), black tea (BT)] were involved in this study in the presence of CBZ, as might happen during clinical therapy. The effects of the beverages on the pharmacokinetics and drug-induced toxicity of CBZ was observed after concomitant administration for a period of 28 days. Accordingly, the influence of altered bioavailability of CBZ on its antiepileptic activity was investigated. A significant shift in the Cmax as well as Tmax of CBZ was observed in the presence of LJ and GFJ. This increase in bioavailability significantly enhanced hepatotoxicity and delayed the onset of tremor and piloerection against pentylene tetrazole (PTZ)-induced seizure in experimental animals. However, increased toxicity of CBZ was found to be absent with BT. Thus, from our observation, LJ or GFJ in the presence of CBZ significantly increased the bioavailability of CBZ, which might lead to increased toxicity and antiepileptic activity of the drug. 相似文献
83.
84.
Metabolic Brain Disease - Alzheimer’s disease (AD) is the most common dementia with currently no known cures or disease modifying treatments (DMTs), despite much time and effort from the... 相似文献
85.
Emy Hiura Aline del Carmen Garcia Lopes Jeanne Saraiva da Paz Maylla Garschagen Gava Mayra Cunha Flecher Manuela Colares Filippe Elias de Freitas Soares Leandro Abreu da Fonseca Tracy Lacerda Jackson Victor de Araújo Fabio Ribeiro Braga 《Parasitology research》2015,114(9):3301-3308
The objective of this study was to evaluate the infectivity of Toxocara canis eggs after interacting with isolated nematophagous fungi of the species Duddingtonia flagrans (AC001) and Pochonia chlamydosporia (VC4), and test the predatory activity of the isolated AC001 on T. canis second stage larvae after 7 days of interaction. In assay A, 5000 embryonated T. canis eggs previously in contact with the AC001 and VC4 isolated for 10 days were inoculated into domestic chickens (Gallus gallus domesticus), and then these animals were necropsied to collect material (digested liver, intestine, muscles and lungs) at 3-, 7-, 14-, and 21-day intervals after inoculation. In assay A, the results demonstrated that the prior interaction of the eggs with isolated AC001 and VC4 decreases the amount of larvae found in the collected organs. Difference (p?<?0.01) was observed in the medium larvae counts recovered from liver, lung, intestine, and muscle of animals in the treated groups when compared to the animals in the control group. At the end of assay A, a percentage reduction of 87.1 % (AC001) and 84.5 % (VC4) respectively was recorded. In the result of assay B, the isolated AC001 showed differences (p?<?0.01) compared to the control group, with a reduction of 53.4 % in the recovery of L2. Through these results, it is justified to mention that prior interaction of embryonated T. canis eggs with the tested fungal isolates were efficient in reducing the development and migration of this parasite, in addition to the first report of proven predatory activity on L2. 相似文献
86.
Marcio Nucci Paula Rocha Braga Simone A. Nouér Elias Anaissie 《The Brazilian journal of infectious diseases》2018,22(6):455-461
Background
The impact of central venous catheter (CVC) removal on the outcome of patients with candidemia is controversial, with studies reporting discrepant results depending on the time of CVC removal (early or any time during the course of candidemia).Objective
Evaluate the effect of time to CVC removal, early (within 48 h from the diagnosis of candidemia) vs. removal at any time during the course of candidemia, on the 30-day mortality.Methods
Retrospective cohort study of 285 patients with candidemia analyzing CVC removal within 48 h (first analysis) or at any time (second analysis).Results
A CVC was in place in 212 patients and was removed in 148 (69.8%), either early (88 patients, 41.5%) or late (60 patients, 28.3%). Overall, the median time to CVC removal was one day (range 1–28) but was six days (range 3–28) for those removed later. In the first analysis, APACHE II score (odds ratio [OR] 1.111, 95% confidence interval [95% CI] 1.066–1.158), removal at any time (OR 0.079, 95% CI 0.021–0.298) and Candida parapsilosis infection (OR 0.291, 95% CI 0.133–0.638) were predictors of 30-day mortality. Early removal was not significant. In the second analysis APACHE II score (OR 1.122, 95% CI 1.071–1.175) and C. parapsilosis infection (OR 0.247, 95% CI 0.103–0.590) retained significance.Conclusions
The impact of CVC removal is dependent on whether the optimal analysis strategy is deployed and should be taken into consideration in future analyses. 相似文献87.
The hybrid structure of ZnO NWs with the presence of different dopants recently has drawn many interests from researchers due to the possibility to integrate multiple functionalities into one single structure. In this article, we investigated the morphology, crystal structure and ferromagnetism of the ZnO@Co/Ni hybrid core@shell NWs prepared by a facile electrochemical deposition method. The results show that a thin layer of Ni and Co coated on the surface of ZnO NWs (confirmed by XRD, EDS, TEM and Raman scattering) can create a significant improvement of ferromagnetic property in such hybrid core@shell NWs. In which, for the coating time of 10, 15, 20 min, the value of Ms is around 0.67, 0.88 and 2.56 emu g−1 for ZnO@Co NWs, and about 0.013, 0.022 and 0.031 emu g−1 for ZnO@Ni NWs, respectively, in comparison with the number of 0.016 emu g−1 for pure ZnO NWs. Interestingly, we also found the temperature dependence of ferromagnetism of such Co/Ni coated ZnO NWs. These results reveal the possibility to employ such hybrid core@shell NWs for many applications, e.g. spin field effect transistors.Facile electrochemical synthesis of ZnO@Co and ZnO@Ni hybrid core@shell nanowires with enhanced ferromagnetism. 相似文献
88.
Tuan-Khoa Nguyen Hoang-Phuong Phan Jisheng Han Toan Dinh Abu Riduan Md Foisal Sima Dimitrijev Yong Zhu Nam-Trung Nguyen Dzung Viet Dao 《RSC advances》2018,8(6):3009
This paper presents for the first time a p-type 4H silicon carbide (4H-SiC) van der Pauw strain sensor by utilizing the strain induced effect in four-terminal devices. The sensor was fabricated from a 4H-SiC (0001) wafer, using a 1 μm thick p-type epilayer with a concentration of 1018 cm−3. Taking advantage of the four-terminal configuration, the sensor can eliminate the need for resistance-to-voltage conversion which is typically required for two-terminal devices. The van der Pauw sensor also exhibits an excellent repeatability and linearity with a significantly large output voltage in induced strain ranging from 0 to 334 ppm. Various sensors aligned in different orientations were measured and a high sensitivity of 26.3 ppm−1 was obtained. Combining these performances with the excellent mechanical strength, electrical conductivity, thermal stability, and chemical inertness of 4H-SiC, the proposed sensor is promising for strain monitoring in harsh environments.This paper presents for the first time a p-type 4H silicon carbide (4H-SiC) van der Pauw strain sensor by utilizing the strain induced effect in four-terminal devices. 相似文献
89.
Mahnaz
M. Abdi Nur Farhana Waheeda Mohd Azli Hong Ngee Lim Paridah Md Tahir Gholamreza Karimi Yeoh Beng Hoong Mohammad Khorram 《RSC advances》2018,8(6):2978
In this research, tannin (TA) extracted from Acacia mangium and a cationic surfactant, cetyltrimethylammonium bromide (CTAB), were used to modify and enhance the physical and electrochemical properties of a polypyrrole (PPy) composite. Brunauer–Emmett–Teller (BET) analysis presented a higher degree of surface area and porosity for the PPy/TA/CTAB nanocomposite. A highly porous and rod like structure with a lumpy surface was observed for PPy/TA prepared in the presence of CTAB by Field Emission Scanning Electron Microscopy (FESEM) and Transmission Electron Microscopy (TEM). Cyclic voltammograms of the modified SPE electrode using PPy/TA/CTAB displayed an enhanced current response compared to the electrode modified with only PPy or PPy/TA. Electrochemical Impedance Spectroscopy (EIS) exhibited a lower value of charge transfer resistance (Rct) and higher electron transfer for the modified electrode, making the nanocomposite a promising candidate for biosensor application.Tannin (TA) extracted from Acacia mangium and a cationic surfactant, cetyltrimethylammonium bromide (CTAB), were used to modify and enhance the physical and electrochemical properties of polypyrrole (PPy) composite. 相似文献
90.
Kimal Chandula Wasalathilake Md Roknuzzaman Kostya Ostrikov Godwin A. Ayoko Cheng Yan 《RSC advances》2018,8(5):2271
Lithium–sulfur (Li–S) batteries are emerging as one of the promising candidates for next generation rechargeable batteries. However, dissolution of lithium polysulfides in the liquid electrolyte, low electrical conductivity of sulfur and large volume change during electrochemical cycling are the main technical challenges for practical applications. In this study, a systematic first-principles density functional theory calculation is adopted to understand the interactions between graphene and graphene with oxygen containing functional groups (hydroxyl, epoxy and carboxyl groups) and sulphur (S8) and long chain lithium polysulfides (Li2S8 and Li2S4). We find the adsorption is dominated by different mechanisms in sulphur and lithium polysulfides, i.e. van der Waals attraction and formation of coordinate covalent Li–O bonds. The adsorption strength is dependent on the inter-layer distance and electron rich functional groups. Through these mechanisms, sulphur and lithium polysulfides can be successfully retained in porous graphene, leading to improved conductivity and charge transfer in the cathode of Li–S batteries.Functionalized graphene can successfully anchor sulfur compounds via moderate interactions, leading to improved conductivity and charge transfer in the cathode of Li–S batteries. 相似文献