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991.
992.

Background

Streptococcus pneumoniae is a leading cause of invasive infection in young children causing morbidity and mortality. Active surveillance systems of invasive pneumococcal disease (IPD) are recommended worldwide. The aim of this study was to estimate the current incidence of IPD and to describe the serotype distribution and the antimocrobial susceptibility of S. pneumoniae isolates in children aged less than 5?years residing in North-West Lombardy, Italy.

Methods

A twelve-month prospective active surveillance system recruited all children aged less than 5?years admitted for suspicion of IPD at emergency room of ten hospitals located in the monitored area. Blood samples were taken in all participants for confirmation of IPD based on isolation of S. pneumoniae from blood. Pneumococcal meningitis and sepsis were additionally confirmed by cerebrospinal fluid analysis. Serotyping and antimicrobial susceptibility testing were performed on isolates from blood.

Results

A total of 15 confirmed cases of IPD were detected among 135 recruited children, including pneumonia (n?=?8), bacteremia (n?=?4), sepsis (n?=?2) and meningitis (n?=?1). The annual IPD incidence rate was 50.0/100,000 (95%CI, 30.5-82.5/100,000). Incidence was 58.3/100,000 (28.8-120.1/100,000) among children aged less than 2?years and 44.4/100,000 (22.9-87.5/100,000) among children aged 2?C4?years. Thirteen isolates were typified. The most common serotype was 19A (23.1%) that together with serotypes 1, 7F and 19F accounted for 69.2% of typified isolates. Serotypes 14, 23F, 12B and 15C were also identified. The 7- and 13-valent pneumococcal conjugate vaccines covered respectively 30.8% and 84.6% of typified IPD cases. One isolate (serotype 15C) was penicillin-resistant and caused meningitis.

Conclusions

The inclusion of the 13-valent pneumococcal conjugate vaccine in immunization programs of young children might be considered to reduce incidence and morbidity of invasive pneumococcal disease in this surveilled population.  相似文献   
993.
Chen XS  Yin YP 《The Lancet infectious diseases》2012,12(4):269; author reply 270-269; author reply 271
  相似文献   
994.
995.
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目的:比较强脉冲光(IPL)联合睑板腺按摩和单纯睑板腺按摩对睑板腺功能障碍(MGD)的短期疗效差异。方法:选取2019-10/2020-01在四川大学华西医院眼科就诊的MGD患者共40例80眼,随机分为试验组和对照组,两组均接受3次治疗,每次治疗中试验组双眼接受IPL联合睑板腺按摩,对照组双眼接受单纯睑板腺按摩,治疗时间间隔为2wk,整个试验期间两组均双眼应用玻璃酸钠每天4次,在每次治疗之前及最后一次治疗2wk后进行指标评估,从而评估IPL联合睑板腺按摩的短期疗效。结果:治疗后两组OSDI、SPEED评分均降低(P<0.05),两组间无差异(P>0.05)。两组睑板腺功能评估(MGE)、泪膜脂质层厚度(LLT)均升高,对照组升高较试验组慢,且第二、三次治疗后试验组MGE高于对照组(P<0.05)。两组泪膜破裂时间(BUT)均升高。两组角膜染色均下降,对照组下降较试验组慢,但两组间无差异(P>0.05)。两组视觉质量持续改善,但对照组改善较试验组慢,两组间无差异(P>0.05)。两组泪液分泌、不完全眨眼比例、睑板腺缺失率无明显变化(P>0.05)。所有受试者未出现皮肤、视力损害、眼压改变、眼前节炎症等并发症。结论:IPL联合睑板腺按摩与单纯睑板腺按摩对MGD均安全有效。IPL见效更快,效果可能有累积效应,在达到一定治疗次数后疗效更好。  相似文献   
998.
Understanding the effects of natural solid particles on the phototransformation of pharmaceuticals in aqueous environments is very important, but studies on this are still limited. In this study, natural sands were selected as a solid particle model due to their wide distribution in surface waters during the rainy season, and the phototransformation of diphenhydramine (DP) in the presence of the sands was investigated. The kinetic studies showed that the natural sands exhibited significant photocatalytic activity for the DP photodegradation, and the activity varied depending on their sources. Scavenging experiments and electron paramagnetic resonance analysis demonstrated that O2˙ and ˙OH were produced in the irradiated natural sand systems, and O2˙ played a more important role than ˙OH in the photodegradation of DP. The results obtained from H2O2 treatment and deoxygenation experiments verified that the generation of radicals was mainly attributed to the low content of natural organic matter (NOM) in the sands. The possible reaction mechanism was that the NOM in the sands was excited and became triplet-state NOM after irradiation, and then induced the generation of free radicals through an electron transfer mechanism, resulting in DP oxidation. This work indicated that natural sand particles were a key factor affecting the phototransformation of drugs, and should be considered in evaluating their fate in natural waters.

Natural sand particles induced the generation of free radicals under simulated solar irradiation, resulting in the enhanced photodegradation of diphenhydramine.  相似文献   
999.
Complex space environments, including microgravity and radiation, affect the body''s central nervous system, endocrine system, circulatory system, and reproductive system. Radiation-induced aberration in the neuronal integrity and cognitive functions are particularly well known. Moreover, ionizing radiation is a likely contributor to alterations in the microbiome. However, there is a lacuna between radiation-induced memory impairment and gut microbiota. The present study was aimed at investigating the effects of simulated space-type radiation on learning and memory ability and gut microbiota in mice. Adult mice were irradiated by 60Co-γ rays at 4 Gy to simulate spatial radiation; behavioral experiments, pathological experiments, and transmission electron microscopy all showed that radiation impaired learning and memory ability and hippocampal neurons in mice, which was similar to the cognitive impairment in neurodegenerative diseases. In addition, we observed that radiation destroyed the colonic structure of mice, decreased the expression of tight junction proteins, and increased inflammation levels, which might lead to dysregulation of the intestinal microbiota. We found a correlation between the brain and colon in the changes in neurotransmitters associated with learning and memory. The 16S rRNA results showed that the bacteria associated with these neurotransmitters were also changed at the genus level and were significantly correlated. These results indicate that radiation-induced memory and cognitive impairment can be linked to gut microbiota through neurotransmitters.

Exposure to 60Co-γ ray impacts learning and memory ability as well as the cell morphology and neurotransmitters in hippocampus, even disrupts the bacterial community in colon.  相似文献   
1000.
Surface acoustic wave (SAW) devices based on piezoelectric thin-films such as ZnO and AlN are widely used in sensing, microfluidics and lab-on-a-chip applications. However, for many of these applications, the SAW devices will inevitably be used in acid or alkali harsh environments, which may cause their early failures. In this work, we investigated the behavior and degradation mechanisms of thin film based SAW devices in acid and alkali harsh environments. Results show that under the acid and alkali attacks, chemical reaction and corrosion of ZnO devices are very fast (usually within 45 s). During the corrosion, the crystalline orientation of the ZnO film is not changed, but its grain defects are significantly increased and the grain sizes are decreased. The velocity of ZnO-based SAW devices is decreased due to the formation of porous structures induced by the chemical reactions. Whereas an AlN thin-film based SAW device does not perform well in acid–alkali conditions, it might be able to maintain a normal performance without obvious degradation for more than ten hours in acid or alkali solutions. This work could provide guidance for the applications of both ZnO or AlN-based SAW devices in acid/alkali harsh environments.

Surface acoustic wave (SAW) devices based on piezoelectric thin-films such as ZnO and AlN are widely used in sensing, microfluidics and lab-on-a-chip applications.  相似文献   
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