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81.
Twenty-nine domestic piglets from pig farms located in three provinces of Thailand between 2003 and 2004 were used as sentinel animals for Japanese encephalitis virus (JEV) circulation. Piglets were used as sentinel to underline, on one hand, the role of domestic pigs as JEV amplifying host and, on another hand, to point out the interest of using sentinel animals for Japanese encephalitis surveillance. JEV activity was demonstrated through i/ antibody detection using a specific ELISA test for the identification of Immunoglobulins of class M and G, ii/ virus isolation on cell culture, after experimental mosquito inoculation for virus amplification. Almost 100% and 83% of the piglets, respectively, had specific IgG and IgM JEV antibodies and 35% yielded a virus isolate. Piglets of the growing farm industry act as virus amplifier increasing the risk of transmission for the human community. Conclusively, since piglets JEV infection appears early in life and is generally clinically unnoticed, it represents an exceptional sentinel model for human health threats, which has to be considered by health authorities.  相似文献   
82.
A pilot study was designed to analyze a potential association between dengue hemorrhagic fever (DHF) incidence and, temperature computed by satellite. DHF is a mosquito transmitted disease, and water vapor and humidity are known to have a positive effect on mosquito life by increasing survival time and shortening the development cycle. Among other available satellite data, Land Surface Temperature (LST) was chosen as an indicator that combined radiated earth temperature and atmospheric water vapor concentration. Monthly DHF incidence was recorded by province during the 1998 epidemic and obtained as a weekly combined report available from the National Ministry of Public Health. Conversely, LST was calculated using remotely sensed data obtained from thermal infrared sensors of NOAA satellites and computed on a provincial scale. Out of nine selected study provinces, five (58.3%) exhibited an LST with a significant positive correlation with rainfall (p < 0.05). In four out of nineteen surveyed provinces (21.3%), LST showed a significant positive correlation with DHF incidence (p < 0.05). Positive association between LST and DHF incidence was significantly correlated in 75% of the cases during non-epidemic months, while no correlation was found during epidemic months. Non-climatic factors are supposed to be at the origin of this discrepancy between seasonality in climate (LST) and DHF incidence during epidemics.  相似文献   
83.
The aerosol solvent extraction system (ASES) process was applied to prepare miconazole (MCZ) liposomes in a dry and reconstitutable form, the optimized temperature and pressure of which were 35 degrees C and 8.0 MPa, respectively. The influence of compositions of phosphatidylcholine (PC), cholesterol (CHOL), and poloxamer 407 (POLOX) as well as the pH of hydration medium on physical and chemical stability of both dry microparticles and liposomes hydrated from them were examined following storage at 4 degrees C and 25 degrees C for 3 months. MCZ microparticles in dry powder were stable on storage at 4 degrees C but degraded considerably after storage at 25 degrees C. MCZ liposomes hydrated from dry ASES-prepared microparticles at pH 4.0 tended to aggregate, whereas those hydrated at pH 7.2 tended to reduce in size on storage, especially with the addition of CHOL. Liposomes with high MCZ content stored at 4 degrees C degraded faster than when stored at 25 degrees C. Addition of POLOX tended to retard the degradation of MCZ liposomes, whereas CHOL appeared to enhance the degradation on storage under both conditions. The chemical degradation of MCZ liposomes appeared to follow the acid-catalyzed hydrolysis. The MCZ liposomes prepared by the ASES process in this study were substantially internalized after being incubated with human lymphocytes.  相似文献   
84.

Purposes  

Ondansetron plus dexamethasone are standard antiemetic agents for highly emetogenic chemotherapy. Metoclopramide is a dopamine antagonist, which may enhance efficacy of ondansetron and dexamethasone. The objective of this study was to assess the efficacy and tolerability of metoclopramide added to standard antiemetic regimen for prophylaxis of cisplatin-induced emesis.  相似文献   
85.
86.
In the year 2001 a large dengue fever (DF)/dengue hemorrhagic fever (DHF) outbreak occurred in Nakhon Pathom Province, Thailand. Three thousand one hundred twelve cases of DHF were reported, an attack rate of 393 per 100,000 population. The Nakhon Pathom Provincial Health Office immediately carried out a control action according to WHO recommendations. Active serological surveys and viral RNA isolation were carried out to detect silent transmission of dengue virus in 329 healthy volunteers in Nakhon Pathom Province subdistricts where the dengue epidemic had the highest rate of infection of 2.5 per 1000. Eight point eight percent of these volunteers had a serum sample positive for DF/DHF virus IgM antibody. The highest prevalence occurred in the 15 to 40 year old group. In two instances viral RNA was detected by PCR and dengue serotype 3 was subsequently identified. The data support the hypothesis of subclinical infection with dengue virus. This high frequency of virus circulation combined with a high population density, urbanization and increasing breeding sites for mosquitoes, needs to be taken into account in the evaluation of viral transmission during and after epidemics. This underlines the importance of community-based control in informing people of their involvement in virus transmission and the importance of personal protection.  相似文献   
87.
RNA amplification by nucleic acid sequence-based amplification (NASBA) was used to detect serotype specific dengue viruses in artificially-infected female Aedes mosquitoes, in comparison with RT-PCR technique. NASBA could detect dengue virus serotype 2 and 4 below 0.1 PFU, which was more sensitive than RT-PCR, but this technique was as sensitive as RT-PCR when detecting dengue virus serotype 1 and 3. Dengue viruses could be detected at the thorax of mosquitoes at 0, 7, and 14 days after inoculation with dengue virus serotype 2. This method should be useful for virological surveillance of dengue infected Aedes mosquitoes, as an early warning system to predict outbreaks of dengue viruses.  相似文献   
88.
What are the risk factors of colonoscopic perforation?   总被引:1,自引:0,他引:1  

Background  

Knowledge of the factors influencing colonoscopic perforation (CP) is of decisive importance, especially with regard to the avoidance or minimization of the perforations. The aim of this study was to determine the incidence and risk factors of CP in one of the endoscopic training centers accredited by the World Gastroenterology Organization.  相似文献   
89.
A facile molten salt technique is an interesting preparation method as it enables mass production of materials. With the use of CsNO3 salt, Cs-intercalated MnO2 hollow microflowers are obtained in this work. δ-MnO2 with a layered structure, instead of other allotropes with smaller structural cavities, is formed and stabilized by large Cs+ ions. Formation of the hollow microflowers is explained based on the Ostwald ripening process. The salt to starting agent ratio has little effect on the crystal structure and morphologies of the products but does influence the crystallinity, the interlayer distance, and the intercalating Cs+ content. The capacity of Cs+ in the structure and the interlayer distance are maximized when the weight ratio of CsNO3 : MnSO4 is 7 : 1. Cs–MnO2 obtained from this optimum ratio has most suitable crystallinity and interlayer distance, and consequently shows a highest specific capacitance of 155 F g−1 with excellent cycling performance. The obtained specific capacitance is comparable to that of other alkaline-intercalated MnO2, suggesting that Cs–MnO2 could be another interesting candidate for supercapacitor electrodes.

Hollow microflowers of Cs intercalated MnO2 binessite are prepared by a facile molten salt method and tested for supercapacitor electrodes.  相似文献   
90.
BackgroundCathodal transcranial direct current stimulation (tDCS) is a noninvasive brain stimulation method for suppressing regional cortical excitability. We examine the safety and antiepileptic efficacy of cathodal tDCS in children with refractory focal epilepsy. Although a prior cathodal tDCS trial in adults with epilepsy revealed EEG improvement, neither the antiepileptic potential nor the safety and tolerability of tDCS has been tested in children.MethodThe study consisted of three phases: 1) a 4-week pre-treatment monitoring period with vital sign measures, EEG, seizure diary, and baseline quality of life (QOL) questionnaire; 2) a single treatment with 1 mA cathodal tDCS for 20 min with cathode positioned over the seizure focus and anode on the contralateral shoulder; 3) follow-ups immediately after stimulation, and at 24, 48 h, and 4 weeks after tDCS with continued seizure diary and epileptic discharge counts on EEG; the QOL questionnaire was also repeated 4 weeks after stimulation. Patients were randomized to receive either single session active or sham tDCS 1 mA, 20 min.ResultsThirty six children (6–15 years) with focal epilepsy were enrolled, 27 in active and 9 in sham group. All patients tolerated tDCS well. No serious adverse events occurred. Active tDCS treatment was associated with significant reductions in epileptic discharge frequency immediately and 24 and 48 h after tDCS. Four weeks after treatment, a small (clinically negligible but statistically significant) decrease in seizure frequency was also detected.ConclusionA single session of cathodal tDCS improves epileptic EEG abnormalities for 48 h and is well-tolerated in children.  相似文献   
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