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991.
Introduction:  Our previous studies demonstrated that three enzymes, γ-glutamyltransferase (GGT), cysteinylglycinase (CGase) and cystalysin, are required for the catabolism of glutathione to produce hydrogen sulfide (H2S) in Treponema denticola . In this study, we examined glutathione catabolism in Aggregatibacter actinomycetemcomitans .
Methods:  The GGT and CGase of A. actinomycetemcomitans were determined by biological methods and GGT was characterized using a molecular biological approach.
Results:  A. actinomycetemcomitans showed GGT and CGase activity, but could not produce H2S from glutathione. The addition of recombinant T. denticola cystalysin, an l -cysteine desulfhydrase, to whole cells of A. actinomycetemcomitans resulted in the production of H2S from glutathione. Subsequently, we cloned A. actinomycetemcomitans GGT gene ( ggt ) and overexpressed the 63 kDa GGT protein. The recombinant A. actinomycetemcomitans GGT was purified and identified. The K cat/ K m of the recombinant GGT from N -γ- l -glutamyl-4-nitroaniline as substrate was 31/μ m /min. The activity of GGT was optimum at pH 6.9–7.1 and enhanced by thiol-containing compounds.
Conclusion:  The results demonstrated that A. actinomycetemcomitans had GGT and CGase activities and that the GGT was characterized. The possible role of A. actinomycetemcomitans in glutathione metabolism and H2S production from oral bacteria was discussed.  相似文献   
992.
糖尿病病人胰岛素泵应用及相关知识调查   总被引:1,自引:0,他引:1  
[目的]探讨糖尿病病人应用胰岛素泵强化治疗的相关知识及需求情况.[方法]采用自行设计的问卷调查表,对60例糖尿病胰岛素泵强化治疗病人进行调查.[结果]病人对胰岛素泵了解甚少,相关知识缺乏,希望接受胰岛素泵知识教育.[结论]胰岛素泵应用现状存在较多问题,影响病人血糖的良好控制,应提高病人对胰岛素泵的认可程度和依从性,提高生活质量.  相似文献   
993.
994.
Immunosuppressive therapy (IST) has provided an alternative treatment option for cure of aplastic anemia patients who cannot receive bone marrow transplantation. Although there have been many recent studies on the efficacy of antithymoglobulin (ATG) combined with cyclosporine A (CsA), there is no data on the correlation between the variability of CsA levels and the response to IST. Therefore, we retrospectively assessed the factors associated with IST efficacy in patients with acquired severe aplastic anemia (SAA). Sixty‐six patients were treated with ATG combined with CsA for 6 months. In the response group, the CsA levels were increased rapidly to more than 200 ng/mL within the first 2 wk after starting the IST. However, the non‐response group had a pattern of slower increase of the CsA levels. The CsA levels, during the first and second week of treatment with IST, were significantly different in the responders and non‐responders. The factors predictive of response to IST and survival were analyzed. The univariate analysis showed that a younger age at the initiation of IST, a high absolute neutrophil count prior to starting IST, a short interval between the diagnosis and initiation of IST, and high CsA levels during the first and second week of IST treatment were positively associated with the response rate and overall survival. The multivariate analysis showed that these four factors were independent factors associated with a longer patient survival. A high response rate was associated with a short interval between diagnosis and initiation of IST as well as high CsA levels during the first and second week of IST. Therefore, early intensification of CsA levels might improve patient outcome.  相似文献   
995.
目的 掌握江西省山丘型血吸虫病传播控制地区野生动物血吸虫感染情况,为实施精准防控措施及实现血吸虫病传播阻断和消除目标提供科学依据。方法 选择江西省血吸虫病疫情较重的山丘型流行区瑞昌市和彭泽县的5个流行村作为调查村。在调查村有螺环境捕捉野鼠等野生动物,收集来自调查村的野生动物肝脏,检查其血吸虫感染情况。在调查村采用间接血凝试验(IHA)筛查、粪便尼龙绢袋集卵孵化法和改良加藤厚涂片法检测人群血吸虫感染,采用粪便塑料杯顶管孵化法检测家畜血吸虫感染;采用系统抽样结合环境抽查法调查钉螺分布,采用环介导等温扩增技术(LAMP)检测钉螺血吸虫感染。结果 在调查村捕获、收购野鼠、黄鼠狼、野猪、麂子和野兔等野生动物或肝脏样本240只(份),其中捕获野鼠172只,血吸虫感染率为2.91%,其他野生动物未发现血吸虫感染;野鼠、麂子和野猪肝毛细线虫感染率分别为12.21%、1.96%和12.50%。调查村人群和家畜中均未发现血吸虫感染;各村平均钉螺密度在0.13~0.80只/0.1 m2,在1个村发现2只检测管钉螺有血吸虫阳性。结论 江西省山丘型传播控制地区野生动物在血吸虫病传播中的作用和潜在风险仍不可忽视;应继续加强监测,并采取有针对性防治措施,以巩固血吸虫病防治成果。  相似文献   
996.
应用高效液相色谱法(HPLC)检测42例正常人,24例肾功能正常之慢性肾炎,12例慢性肾炎肾功能不全氮质血症期患者及21例尿毒症期患者尿FPA水平,其均值分别为:25.40±10.30ng/mgCr、26.99±5.77ng/mgCr、38.81±6.28ng/mgCr、79.74±18.76ng/mgCr。结果显示:氮质血症期组尿FPA水平明高于正常对照及肾功能正常之慢性肾炎组(P<0.01),尿毒症期组尿FPA显著高于氮质血症期组(P<0.01)。监测尿FPA水平与血浆肌酐浓度显示二者呈正相关性(r=0.9120,P<0.01)。揭示,慢性肾炎肾功能不全患者循环血液处于异常高凝状态,其严重程度与疾病的发生、发展密切相关,监测其尿FPA水平能较敏感地反映肾功能状态。  相似文献   
997.
目的 观察脾虚患者胃粘膜超氧化物歧化酶(SOD)活性与前列腺素(PG)的关系。 方法 72例慢性胃病住院患者,按中医辨证分成脾虚组和肝气犯胃组,分别测出胃粘膜SOD活性,以及前列腺素和血栓素A_2的代谢产物6-酮-PGF_(1a)和血栓素B_2(TXB_2)的含量,分析SOD与6-酮-PGF_(1a)和TXB_2的相关性。 结果 脾虚组患者胃粘膜SOD活性为2.7±1.1 U/mg湿重,明显低于肝气犯胃组的4.2±1.7 U/mg湿重(P<0.01);脾虚组胃粘膜6-酮-PGF_(1a)含量为115.7±60.7 pg/mg湿重,亦明显低于肝气犯胃组的289.6±154.2 pg/mg湿重(P<0.01)。SOD活性与6-酮-PGF_(1a)含量呈线性正相关(P<0.05)。 结论 脾虚证患者胃粘膜内自由基代谢紊乱,表现为SOD活性及抗氧化能力低下,并且与胃粘膜PG代谢的改变存在着一定的关系。  相似文献   
998.
Objective. Recommendations and/or guidelines represent a popularway of integrating evidence-based medicine into clinical practice.The 3E Initiatives is a multi-national effort to develop recommendationsfor the management of rheumatic diseases, which involves a largenumber of experts combined with practising rheumatologists addressingspecific questions relevant to clinical practice. Methods. Ten countries participated in three rounds of discussionsand votes concerning the management of AS. A set of nine questionswas formulated in the domains of diagnosis, monitoring and treatment,after a Delphi procedure. A literature search in MedLine wasconducted. Predefined outcome parameters for the domains ofdiagnosis, monitoring and treatment were assessed. The evidenceto support each proposition was evaluated and scored. Afterdiscussion and votes, the final recommendations were presentedusing brief statements by each national group, following whichthe final international recommendations were formulated. Results. A total of 2699 papers were found and 467 were selectedfor analysis. Twelve key recommendations were developed: threein the domain of diagnosis addressing general diagnostic considerations,early AS diagnosis and general practitioners’ referralrecommendations; three concerning monitoring of AS disease activity,severity and prognosis; six concerning pharmacological treatment(except biologics): non-steroidal anti-inflammatory drugs/COX-IIinhibitors, bisphosphonates and treatment of enthesitis. Thecompiled agreement among experts ranged from 72% to 93%. Conclusion. Recommendations for the management of AS were developedusing an evidence-based approach followed by expert/physicianconsensus with high level of agreement. Involvement of a largerand more representative group of rheumatologists may improvetheir dissemination and implementation in daily clinical practice. KEY WORDS: Ankylosing spondylitis, Systemic literature search, Recommendations, Non-steroidal anti-inflammatory drugs, COX-II inhibitors, Monitoring, Diagnosis, Treatment  相似文献   
999.
茶树籽对钉螺生殖腺和肝脏的影响   总被引:8,自引:0,他引:8  
目的 :了解钉螺组织经茶树籽处理的影响。方法 :应用电镜技术观察处理后的钉螺肝脏及生殖腺组织的超微结构。结果 :钉螺在茶树籽作用 2 4 h后 ,肝内细胞受损。雄性生殖细胞有凝固性及溶解性变化 ;成熟精子细胞膜肿胀与内部结构分离 ,线粒体鞘呈现凝集型 ,支持细胞可见凝固性改变 ,且彼此断裂并与生殖细胞分离。雌性钉螺生殖腺可见卵细胞肿胀 ,严重时滤泡细胞有破裂 ,卵细胞膜则可丧失完整性。结论 :茶树籽能损伤钉螺的生殖腺和肝脏。  相似文献   
1000.
A radiative vapor condenser sheds heat in the form of infrared radiation and cools itself to below the ambient air temperature to produce liquid water from vapor. This effect has been known for centuries, and is exploited by some insects to survive in dry deserts. Humans have also been using radiative condensation for dew collection. However, all existing radiative vapor condensers must operate during the nighttime. Here, we develop daytime radiative condensers that continue to operate 24 h a day. These daytime radiative condensers can produce water from vapor under direct sunlight, without active consumption of energy. Combined with traditional passive cooling via convection and conduction, radiative cooling can substantially increase the performance of passive vapor condensation, which can be used for passive water extraction and purification technologies.

Energy and clean water are global challenges that are intertwined in an unfavorable way: even in areas where water is abundant, energy may not be available to purify it for human use (1, 2). There has been strong interest in developing passive technologies to purify or harvest water without using fuel or electricity. In this context, passive vapor condensation becomes particularly important because many passive water technologies go through the vapor phase of water in their harvesting or purification processes.Traditional vapor condensation technique is based on convective and conductive heat exchange with ambient environments. This technique is widely used in systems with hot vapors (36). However, with ever-increasing emphasis on passive systems, there are many situations in which warm- or even room-temperature vapor needs to be effectively condensed, such as extracting water from atmosphere (79) and warm vapor generated from high-efficiency solar evaporation (10). For vapor at such temperatures, most traditional condensers fail. For this reason, there is a clear need for a condensation technique to complement traditional condensers.A different technique is based on radiative vapor condensation. Darkling beetles in the Namib desert (11) use this technique to collect water. Their bodies function as a cooling surface by shedding thermal energy through midinfrared (mid-IR) radiation toward a clear nighttime sky, generating dew from humid air. This mechanism is also used by commercial radiative dew condensers (79). However, neither Namib beetle nor existing dew condensers can operate in the daytime (7). Those nighttime radiative condensers are incompatible with many emerging water technologies that require 24 h operation or direct access to sunlight.Recently, Fan et al. showed that passive radiative cooling to subambient temperatures can be realized even during the daytime, by integrating a high-efficiency solar reflector with a high-emissivity thermal emitter in the mid-IR atmospheric transparency window (12). Using this work as a basis, here we demonstrate a daytime radiative condenser. Compared to existing radiative vapor condensers (79), our condenser can function even in the presence of sunlight, which is essential for integration into passive water-harvesting systems that mainly operate during daytime.  相似文献   
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