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91.
92.
研究森林可燃物燃烧释放的细颗粒物(PM2.5)的排放因子对于揭示森林火灾对大气和生态系统的影响至关重要,而水溶性离子是细颗粒物的重要化学成分,对颗粒物的形成具有重要意义。利用自主设计的生物质燃烧系统,模拟内蒙古大兴安岭5种典型乔木(蒙古栎、白桦、兴安落叶松、黑桦、山杨)的3种组成部分(树干、树枝、树皮)及其地表死可燃物(凋落物层、半腐殖质层、腐殖质层)以及3种典型灌木(平榛、二色胡枝子、兴安杜鹃)树枝燃烧,采用ISC1100离子色谱分析仪测定2种燃烧状态(阴燃和明燃)下PM2.5中水溶性离子(Na+、NH4+、K+、Mg2+、Ca2+、F-、Cl-、NO3-、NO2-、SO42-)的排放因子。结果表明:乔木所有组成部分及其地表死可燃物和灌木树枝燃烧所排放PM2.5中检测到的水溶性离子,阴燃以K+、Cl-和Na+为主要组分,明燃以K+、Cl-和SO42-为主要组分。不同燃烧状态下相同乔木树种及其地表死可燃物和相同灌木排放PM2.5中检测到的水溶性离子总量均存在显著差异。灌木树枝在阴燃期间PM2.5中水溶性无机离子的排放因子比明燃更高。乔木释放的PM2.5中阳离子与阴离子的比率为1.26,地表死可燃物为1.12,灌木为2.0,表明颗粒物呈碱性。内蒙古大兴安岭的森林大火不会通过释放水溶性离子导致生态系统的酸化。  相似文献   
93.
BackgroundThis study examined usefulness and efficiency of Lurasidone in appraisal with the placebo as for the treatment of Bipolar Disorders.MethodsSeven treatment centers in Pakistan were selected for the purpose of starting a six week-long control trial (randomized and double-blind placebo). 76 subjects, already diagnosed with Bipolar I or II based on DSM 5 diagnosis, were selected after randomization. Patients were allocated in one of the two groups. Primary efficacy of the drug was measured using Young Mania Rating Scale. Positive response of the drug was defined as 50% reduction in symptoms from the baseline/13 point less than the baseline score on Young Mania Rating Scale. Efficacy and safety of the drug was assessed using variety of markers such as administering extra-pyramidal symptoms rating scale, adverse side effects reported, electrocardiograms, body weight, vital signs changes, and laboratory investigations.ResultsPatients treated with Lurasidone showed enhanced improvement in their overall health and symptoms manifestation in comparison to patients who were given placebo. Lurasidone treated patients showed a better response to the drug (66%), in comparison with the placebo treated patients (42%).LimitationsStudy was conducted on small scale due to complexity.ConclusionPatients treated with Lurasidone showed reduction in bipolar symptoms and tolerate the drug well.  相似文献   
94.

Background  

Obesity is rapidly becoming a worldwide epidemic that affects children and adults. Some studies have shown a relationship between obesity and infertility, but until now it remains controversial. Thus, the aim of the present study was to investigate the effect of high-fat diet-induced obesity on male reproductive parameters.  相似文献   
95.
Phytochemical investigations were performed on the EtOAc-soluble fraction of the whole plant of the sky flower (Duranta repens) which led to the isolation of the iridoid glycosides 1-6. Their structures were elucidated by both 1D and 2D NMR spectroscopic analysis. All the compounds showed potent antioxidative scavenging activity in four different tests, with half maximal inhibitory concentration (IC(50)) values in the range 0.481-0.719 mM against DPPH radicals, 4.07-17.21 μM for the hydroxyl radical (·OH) inhibitory activity test, 43.3-97.37 μM in the total reactive oxygen species (ROS) inhibitory activity test, and 3.39-18.94 μM in the peroxynitrite (ONOO(-)) scavenging activity test. Duranterectoside A (1) displayed the strongest scavenging potential with IC(50) values of (0.481 ± 0.06 mM, 4.07 ± 0.03, 43.30 ± 0.05, 3.39 ± 0.02 μM) for the DPPH radicals, ·OH inhibitory activity test, total ROS inhibitory activity test and the ONOO(-) scavenging activity test, respectively.  相似文献   
96.
目的对长爪沙鼠线粒体ATPase8,ATPase6,COX3基因全序列进行测定,并对其进行鉴定及进化分析。方法根据长爪沙鼠已知基因序列设计引物,采用PCR产物测序法,对目的片段进行测序鉴定。结合已公布啮齿类动物ATPase8,ATPase6,COX3基因序列,分析其碱基组成、遗传距离、并基于最小进化法和UPGMA法构建系统进化树。结果获得长爪沙鼠线粒体ATPase8,ATPase6,COX3基因全序列,其与家鼠、小家鼠和仓鼠均具有较高的同源性(76~98%);进化分析结果显示,长爪沙鼠与家鼠、黑家鼠和仓鼠遗传距离较近;碱基G的含量分别为6.9%,10.7%,15.2%,符合mtDNA的特点;A+T含量分别为68.2%,64.1%,59.2%,明显低于G+C含量,符合哺乳动物的特点。结论本研究为首次获得长爪沙鼠ATPase8,ATPase6,COX3基因全序列,长爪沙鼠与家鼠、黑家鼠和仓鼠具有较近遗传距离,本研究为长爪沙鼠进化研究、线粒体的结构和功能研究奠定基础。  相似文献   
97.
A 12-year-old spayed female mixed-bred dog presented with nasal bleeding of 2 days duration and a skin nodule in the left flank. No abnormalities were found in coagulation profiles and blood pressure. Cytological evaluation of the nodule revealed numerous characteristic round organisms having a nucleus and a bar within macrophages and in the background, consistent with leishmaniasis. In vitro culture was unsuccessful but PCR of the nodular aspirate identified the organisms as Leishmania infantum, and the final diagnosis was canine leishmaniasis. No history of travel to endemic countries was noted. Because the dog had received a blood transfusion 2 years before the illness, serological screening tests were performed in all donor dogs of the commercial blood bank using the commercial Leishmania ELISA test kit, and there were no positive results. Additional 113 dogs with hyperglobulinemia from Seoul were also screened with the same kits but no positive results were obtained. To the best of the author''s knowledge this is the first autochthonous case of canine leishmaniasis in Korea.  相似文献   
98.
99.
There is ample experimental evidence supporting the hypothesis that the brain serotonergic system is involved in the control of chronic social defeat stress (CSDS), depression, and anxiety. The study aimed to analyze mRNA levels of the serotonergic genes in the raphe nuclei of midbrain that may be associated with chronic social defeats consistently shown by male mice in special experimental settings. The serotonergic genes were the Tph2, Sert, Maoa, and Htr1a. The Bdnf and Creb genes were also studied. The experimental groups were composed of male mice with experience of defeats in 21 daily encounters and male mice with the same track record of defeats followed by a no-defeat period without agonistic interactions (relative rest for 14 days). It has been shown that mRNA levels of the Tph2, Maoa, Sert, Htr1a, Bdnf, and Creb genes in the raphe nuclei of defeated mice are decreased as compared with the controls. The expression of the serotonergic genes as well as the Creb gene is not restored to the control level after the 2 weeks of relative rest. mRNA levels of Bdnf gene are not recovered to the control levels, although some upregulation was observed in rested losers. CSDS experience inducing the development of mixed anxiety/depression-like state in male mice downregulates the expression of serotonergic genes associated with the synthesis, inactivation, and reception of serotonin. The Bdnf and Creb genes in the midbrain raphe nuclei are also downregulated under CSDS. Period of relative rest is not enough for most serotonergic genes to recover expression to the control levels.  相似文献   
100.
2004—2005年,在内蒙古锡林郭勒盟阿巴嘎旗和东乌珠穆沁旗研究了肝毛细线虫病对黑线毛足鼠种群感染情况,分析肝毛细线虫对黑线毛足鼠的感染率与鼠体年龄以及种群密度的关系。结果表明,黑线毛足鼠达到一定的年龄(或体质量)才可感染肝毛细线虫病,最低感染个体体质量为14.6g。肝毛细线虫对低龄鼠的感染检出率比较低,而对成体鼠感染检出率较高,其感染率和感染度均随着个体年龄的增长而增高(感染率与年龄:r=0.97,P<0.05;感染度与年龄:r=0.93,P<0.05)。此外,黑线毛足鼠体质量与肝毛细线虫感染率和感染度也存在显著的相关关系(感染率与体质量:r=0.99,P<0.05;感染度与体质量:r=0.95,P<0.05),黑线毛足鼠的种群密度则对肝毛细线虫的感染率(r=0.27,P>0.05)和平均感染度(r=0.41,P>0.05)没有明显的影响,其感染率可能与地区不同有关。  相似文献   
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