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91.
《Journal of Natural History》2012,46(6):1353-1365
Two new genera of Pilumnidae each with a single new species are described from southeastern Queensland waters. Priapipilumnus is defined by the greatly swollen base and simple blunt apex of the male first pleopod and the concomitant posteriorly protruding, bilobed, third abdominal segment. Takedana is separable by the very short spinous anterolateral margins, the swollen branchial regions, the moderately short walking legs, and the strongly spined chelae. Actumnus pugilator is reassigned to Bathypilumnus Ng and Tan, 1984. 相似文献
92.
报道贵州省织金洞弱蛛科蜘蛛一新属、新种:黔弱蛛属Qianleptoneta gen.nov.,五刺黔弱蛛Qianleptoneta quinquespinata sp.nov.。模式标本保存于河北大学博物馆。文中测量单位为mm。 相似文献
93.
通过对福建武夷山保护区松毛虫属及其近缘属昆虫调查和已有资料的分析研究,本文记述武夷山保护区松毛虫属及其近缘属共16种(杂毛虫属8种、松毛虫属6种、云毛虫属1种、丫毛虫属1种),占福建省已知种类89%。文中列出分属检索表。 相似文献
94.
能乃扎布 《内蒙古师范大学学报(自然科学版)》1989,(4)
本文记录了内蒙古长蝽科Lygaeidae莎长蝽属Cymus Hahn 2种,其中棕莎长蝽C.claviculus (Fall.)为国内新纪录种。本文对内蒙古莎长蝽检索的同时,对国内新纪录种进行了描述。 相似文献
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97.
Jeng JH Wang YJ Chang WH Wu HL Li CH Uang BJ Kang JJ Lee JJ Hahn LJ Lin BR Chang MC 《Cellular and molecular life sciences : CMLS》2004,61(1):83-96
Betel quid (BQ) chewing shows a strong correlation to the incidence of oral submucous fibrosis (OSF), leukoplakia and oral cancer. BQ contains mainly areca nut, lime, Piper betle leaf (PBL) and the inflorescence of P. betle (IPB). Hydroxychavicol (4-allyl-catechol, HC), as a major phenolic compound in PBL and IPB, is shown to induce oxidative stress, glutathione (GSH) depletion and cell cycle deregulation. Using bivariate BrdU/PI flow cytometry, KB cells in DNA synthesis (S phase) are shown to be sensitive to the toxic effect of HC and show cell cycle arrest and apoptosis following exposure to 0.1 and 0.3 mM HC. HC-induced apoptosis and cell cycle arrest are associated with mitochondrial membrane potential (m) depolarization as revealed by a decrease in rhodamine fluorescence. N-acetyl-L-cysteine (1 mM), superoxide dismutase (100 U/ml) and catalase (1000 U/ml) were effective in prevention of HC-induced GSH depletion (as indicated by chloromethylfluorescein fluorescence), reactive oxygen species (ROS) production (by dichlorofluorescein fluorescence), cell cycle arrest and apoptosis. However, dimethylthiourea (2 mM), neocuproine (1 mM), 1,10-phenanthroline (200 M) and desferrioxamine (0.5 mM) showed little effect on HC-induced cell changes. HC elevated the cellular and mitochondrial GSH levels at moderate concentrations (0.05–0.1 mM), whereas at a concentration of 0.3 mM, inhibitory effects were noted. These results indicate that HC consumption may be associated with BQ-chewing-related oral mucosal diseases via GSH depletion, ROS production, mitochondrial dysfunction, cell cycle disturbance and the induction of apoptosis. These events are related to the production of superoxide radicals and hydrogen peroxide.Received 9 July 2003; received after revision 28 September 2003; accepted 24 October 2003 相似文献
98.
在提出施工企业安全绩效评价指标体系的基础上,运用灰色关联投影法对企业安全绩效进行评价。为避免指标的相对重要程度因人为赋权的主观性影响和指标权重分配的均衡化以及指标之间因量纲不同而对权重的影响,采取了变异系数法来对各指标确定权重。之后针对实地考察的施工企业进行实证分析,运用比较安全学的思想对安全绩效进行纵向对比,依据评价体系灰色关联度大小来判断施工企业安全绩效的水平高低。进而诊断出各企业安全绩效的优劣,为同类型的企业实际开展安全绩效评价提供指导性的方向和建议。 相似文献
99.
100.
Peschke E Ebelt H Brömme HJ Peschke D 《Cellular and molecular life sciences : CMLS》2000,57(1):158-164
This study compares functional and morphological alterations caused by application of alloxan, streptozotocin, xanthine oxidase/hypoxanthine
(generation of reactive oxygen species), or S-nitroso-N-acetyl-D,L-penicillamine (SNAP, liberation of nitric oxide) to isolated
rat pancreatic islets in vitro. In perifusion experiments, membrane leakage—detected by non-stimulated insulin release—was
found after application of all drugs, but showed a substance-specific time pattern. Twenty-four hours after application of
the classical diabetogens (alloxan or streptozotocin), potassium chloride- and glucose-stimulated insulin secretion were markedly
reduced, while a persistent reduction was observed neither after exposure to xanthine oxidase/hypoxanthine, nor to SNAP. Morphological
analysis of the islets revealed that nearly all β-cells were destroyed following alloxan or streptozotocin treatment, while the majority of β-cells were configured regularly after application of xanthine oxidase/hypoxanthine or SNAP. Necrotic cells found after xanthine
oxidase/hypoxanthine usually differed in morphology from those observed after application of the classical diabetogens. While
the former cells were characterised by swollen nuclei, the latter had shrunken nuclei with irregular condensed chromatin.
Apoptosis was found only following nitric oxide exposure. Due to these differences, it seems unlikely that alloxan, streptozotocin,
xanthine oxidase/hypoxanthine, and nitric oxide have a common major feature in their toxic action.
Received 16 September 1999; received after revision 15 November 1999; accepted 26 November 1999 相似文献