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991.
小球藻用于生物柴油生产的研究进展 总被引:1,自引:0,他引:1
目的:对小球藻(Chlorella)生产生物柴油的研究做一综述。方法:查阅近年来国内外小球藻用于生物柴油生产的相关文献,并进行综合分析。结果:微藻生物柴油是具有广泛发展前景的生物柴油,小球藻是目前研究较深入、非常有吸引力的、用于生产生物柴油的微藻藻种,是优质的生物柴油原料,具有其他生物柴油原料不可比拟的优势。随着工程技术的发展和研究的不断深入,探索适宜的小球藻规模化培养方法以期获得质与量兼得的高品质油脂成为研究目标,相信该目标在不久的将来就会实现。结论:小球藻在生物柴油生产领域具有广阔的发展前景。 相似文献
992.
Reproductive parasites such as Wolbachia are extremely widespread amongst the arthropods and can have a large influence over the reproduction and fitness of their hosts. Undetected infections could thus confound the results of a wide range of studies that focus on aspects of host behavior, reproduction, fitness, and degrees of reproductive isolation. This potential problem has already been underlined by work investigating the incidence of Wolbachia infections in stocks of the model system Drosophila melanogaster. Here we survey a range of lab stocks of further commonly used model arthropods, focusing especially on the flour beetles Tribolium castaneum and Tribolium confusum, the cowpea weevil Callosobruchus maculatus and related species (Coleoptera: Tenebrionidae and Bruchidae). These species are widespread stored product pests so knowledge of infections with symbionts further has potential use in informing biocontrol measures. Beetles were assessed for infection with 3 known microbial reproductive parasites: Wolbachia, Rickettsia, Spiroplasma. Infections with some of these microbes were found in some of the lab stocks studied, although overall infections were relatively rare. The consequences of finding infections in these or other species and the type of previous studies likely to be affected most are discussed. 相似文献
993.
目的:探讨ST段抬高急性心肌梗死(ST-elevation myocardial infarction,STEMI)患者靶血管长病变(病变>25 mm)急诊经皮冠状动脉介入(percutaneous coronary intervention,PCI)治疗的临床疗效及安全性。方法:回顾性收集2009年1月-2010年6月因STEMI就诊于沈阳军区总医院并急诊行PCI处理的患者442例,以靶病变长度分为两组,即≤25 mm为短病变组(n=235)和>25mm为长病变组(n=207),均急诊行PCI治疗,分析和比较两组患者术前的基线资料、术中资料及并发症的发生情况、辅助措施(临时起搏、IABP、血栓抽吸装置)应用情况,术后30天、2年电话或临床随访,记录主要不良心血管事件(major adverse cardiac events,MACE)的发生情况。结果:与短病变组比较,长病变组吸烟者更多(81.6%vs 62.6%,P=0.000);以三支病变偏多(34.8%vs 24.7%,P=0.037);多枚支架使用率更高(1.47±0.63 vs 1.04±0.28,P=0.000),平均支架总长度显著增加(29.80±7.02 mm vs 22.95±5.58mm,P=0.000),手术成功率、术中并发症及辅助措施应用情况比较差异无统计学意义(P>0.05),30天及2年随访MACE的发生率比较差异无统计学意义(P>0.05)。结论:与急诊PCI治疗的STEMI短病变患者对比,长病变患者虽然病变复杂,多枚支架使用率高,平均支架总长度增加,但术中并发症、30天、2年内MACE与短病变患者相当,提示在以药物洗脱支架为主的介入治疗时代,急诊PCI处理STEMI靶血管长病变具有良好的疗效及安全性。 相似文献
994.
Woo Hwi Yang Oliver Heine Sebastian Pauly Pilsang Kim Wilhelm Bloch Joachim Mester Marijke Grau 《PloS one》2015,10(4)
Purpose
Rapid weight reduction is part of the pre-competition routine and has been shown to negatively affect psychological and physiological performance of Taekwondo (TKD) athletes. This is caused by a reduction of the body water and an electrolyte imbalance. So far, it is unknown whether weight reduction also affects hemorheological properties and hemorheology-influencing nitric oxide (NO) signaling, important for oxygen supply to the muscles and organs.Methods
For this purpose, ten male TKD athletes reduced their body weight by 5% within four days (rapid weight reduction, RWR). After a recovery phase, athletes reduced body weight by 5% within four weeks (gradual weight reduction, GWR). Each intervention was preceded by two baseline measurements and followed by a simulated competition. Basal blood parameters (red blood cell (RBC) count, hemoglobin concentration, hematocrit, mean corpuscular volume, mean cellular hemoglobin and mean cellular hemoglobin concentration), RBC-NO synthase activation, RBC nitrite as marker for NO synthesis, RBC deformability and aggregation parameters were determined on a total of eight investigation days.Results
Basal blood parameters were not affected by the two interventions. In contrast to GWR, RWR decreased activation of RBC-NO synthase, RBC nitrite, respective NO concentration and RBC deformability. Additionally, RWR increased RBC aggregation and disaggregation threshold.Conclusion
The results point out that a rapid weight reduction negatively affects hemorheological parameters and NO signaling in RBC which might limit performance capacity. Thus, GWR should be preferred to achieve the desired weight prior to a competition to avoid these negative effects. 相似文献995.
In this paper, an analogue of hirsutine (compound 1) has been synthesized and evaluated as an anti-hypertension agent, which exhibits extraordinary effects on the contractile response of thoracic aorta rings from male SD rats in vitro (IC50 = 1.129×10-9±0.5025) and the abilities of reducing the systolic blood pressure (SBP) and heart rate (HR) of SHR in vivo. The mechanism investigation reveals that the vasodilatation induced by compound 1 is mediated by both endothelium-dependent and -independent manners. The relaxation in endothelium-intact aortic rings induced by compound 1 can be inhibited by L-NAME (1×10-6 mol•L-1) and ODQ (1×10-6 mol•L-1). Moreover, compound 1 can also block Ca2+ influx through L-type Ca2+ channels and inhibit intracellular Ca2+ release while no effect on K+ channel has been observed. All these data demonstrated that the NO/cyclic GMP pathway can be involved in endothelium-dependent manner induced by compound 1. Meanwhile the mechanism on the vasodilatation of compound 1 probably also related to blockade of Ca2+ influx through L-type Ca2+ channels and inhibition of intracellular Ca2+ release may have no relationship with K+ channels. 相似文献
996.
997.
Sabrina Klix Antje Els Katharina Paul Andreas Graessl Celal Oezerdem Oliver Weinberger Lukas Winter Christof Thalhammer Till Huelnhagen Jan Rieger Heidrun Mehling Jeanette Schulz-Menger Thoralf Niendorf 《PloS one》2015,10(1)
Purpose
This study examines the subjective acceptance during UHF-CMR in a cohort of healthy volunteers who underwent a cardiac MR examination at 7.0T.Methods
Within a period of two-and-a-half years (January 2012 to June 2014) a total of 165 healthy volunteers (41 female, 124 male) without any known history of cardiac disease underwent UHF-CMR. For the assessment of the subjective acceptance a questionnaire was used to examine the participants experience prior, during and after the UHF-CMR examination. For this purpose, subjects were asked to respond to the questionnaire in an exit interview held immediately after the completion of the UHF-CMR examination under supervision of a study nurse to ensure accurate understanding of the questions. All questions were answered with “yes” or “no” including space for additional comments.Results
Transient muscular contraction was documented in 12.7% of the questionnaires. Muscular contraction was reported to occur only during periods of scanning with the magnetic field gradients being rapidly switched. Dizziness during the study was reported by 12.7% of the subjects. Taste of metal was reported by 10.1% of the study population. Light flashes were reported by 3.6% of the entire cohort. 13% of the subjects reported side effects/observations which were not explicitly listed in the questionnaire but covered by the question about other side effects. No severe side effects as vomiting or syncope after scanning occurred. No increase in heart rate was observed during the UHF-CMR exam versus the baseline clinical examination.Conclusions
This study adds to the literature by detailing the subjective acceptance of cardiovascular magnetic resonance imaging examinations at a magnetic field strength of 7.0T. Cardiac MR examinations at 7.0T are well tolerated by healthy subjects. Broader observational and multi-center studies including patient cohorts with cardiac diseases are required to gain further insights into the subjective acceptance of UHF-CMR examinations. 相似文献998.
The primary approach used to conserve tropical biodiversity is in the establishment of protected areas. However, many tropical nature reserves are performing poorly and interventions in the broader landscape may be essential for conserving biodiversity both within reserves and at large. Between October 2010 and 2012, we conducted bird surveys in and around a recently established nature reserve in Xishuangbanna, China. We constructed a checklist of observed species, previously recorded species, and species inferred to have occurred in the area from their distributions and habitat requirements. In addition, we assessed variation in community composition and habitat specificity at a landscape-scale. Despite the fact that the landscape supports a large area of natural forest habitat (~50,000 ha), we estimate that >40% of the bird fauna has been extirpated and abundant evidence suggests hunting is the primary cause. A large proportion (52%) of the bigger birds (>20 cm) were extirpated and for large birds there was a U-shaped relationship between habitat breadth and extirpation probability. Habitat specificity was low and bird communities were dominated by widespread species of limited conservation concern. We question whether extending tropical protected area networks will deliver desired conservation gains, unless much greater effort is channeled into addressing the hunting problem both within existing protected areas and in the broader landscape. 相似文献
999.
1000.
Wei Guo Mengxia Jin Zhaoxia Miao Kai Qu Xia Liu Peicheng Zhang Hailin Qin Haibo Zhu Yinghong Wang 《PloS one》2015,10(6)
2'', 3'', 5''-tri-O-acetyl-N6-(3-hydroxyphenyl) adenosine (also known as WS070117) is a new adenosine analog that displays anti-hyperlipidemic activity both in vitro and in vivo experiments as shown in many preliminary studies. Due to its new structure, little is known about the metabolism of WS070117. Hence, the in vivo metabolites of WS070117 in rat urine following oral administration were investigated. Identification of the metabolites was conducted using the combination of high-performance liquid chromatography (HPLC) coupled with diode array detector (DAD), ion trap electrospray ionization-mass spectrometry (ESI-MS), and off-line microprobe nuclear magnetic resonance (NMR) measurements. Seven metabolites were obtained as pure compounds at the sub-milligram to milligram levels. Results of structure elucidation unambiguously revealed that the phase I metabolite, N6-(3-hydroxyphenyl) adenosine (M8), was a hydrolysate of WS070117 by hydrolysis on the three ester groups. N6-(3-hydr-oxyphenyl) adenine (M7), also one of the phase I metabolites, was the derivative of M8 by the loss of ribofuranose. In addition to two phase I metabolites, there were five phase II metabolites of WS070117 found in rat urine. 8-hydroxy-N6-(3-hydroxy-phenyl) adenosine (M6) was the product of M7 by hydrolysis at position 8. The other four were elucidated to be N6-(3-O-β-D-glucuronyphenyl) adenine (M2), N8-hydroxy-N6-(3-O-sulfophenyl) adenine (M3), N6-(3-O-β-D-glucuronyphenyl) adenosine (M4), and N6-(3-O- sulfophenyl) adenosine (M5). Phase II metabolic pathways were proven to consist of hydroxylation, glucuronidation and sulfation. This study provides new and valuable information on the metabolism of WS070117, and also demonstrates the HPLC/MS/off-line microprobe NMR approach as a robust means for rapid identification of metabolites. 相似文献