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Marine environment has been identified as a huge reservoir of novel biometabolites that are beneficial for medical treatments, as well as improving human health and well-being. Sponges have been highlighted as one of the most interesting phyla as new metabolites producers. Dactylospongia elegans Thiele (Thorectidae) is a wealth pool of various classes of sesquiterpenes, including hydroquinones, quinones, and tetronic acid derivatives. These metabolites possessed a wide array of potent bioactivities such as antitumor, cytotoxicity, antibacterial, and anti-inflammatory. In the current work, the reported metabolites from D. elegans have been reviewed, including their bioactivities, biosynthesis, and synthesis, as well as the structural-activity relationship studies. Reviewing the reported studies revealed that these metabolites could contribute to new drug discovery, however, further mechanistic and in vivo studies of these metabolites are needed.  相似文献   
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In this investigation the pharmacokinetics of three commonly used antibiotics, ampicillin trihydrate (10 mg/kg), gentamicin sulphate (3 mg/kg) and oxytetracycline hydrochloride (5 mg/kg), given intravenously, were each studied in five Nubian goats and five desert sheep. The pharmacokinetic parameters were described by a two-compartment open model. The results indicated that there were significant differences between the two species in some kinetic parameters of ampicillin and oxytetracycline but not gentamicin. Ampicillin elimination half life ( t 1/2β) in goats (1.20 h) was shorter than that in sheep (2.48 h), and its clearance ( Cl ) significantly higher in goats (2921mL/h·kg) compared to sheep (262 mL/h·kg) ( P < 0.01). Ampicillin volume of distribution ( V darea) was found to be significantly larger in goats (5673 mL/kg) than in sheep (992 mL/kg) ( P < 0.01). For oxytetracycline, the t 1/2β in goats (3.89 h) was significantly shorter than that in sheep (6.30 h) and the Cl value in goats (437 mL/h·kg) was significantly higher than in sheep (281 mL/h·kg). The results suggest that when treating sheep and goats, the pharmacokinetic differences between the two species must be considered in order to optimize the therapeutic doses of ampicillin and oxytetracycline.  相似文献   
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This study was carried out to assess the ability of using pawpaw (Carica papaya) seeds as a natural reproduction inhibitor for tilapia fish (Oreochromis niloticus) culture to control its breeding. Biochemical, physiological and histopathological effects ofpawpaw seeds on male tilapia fish were also determined. Mature male tilapia were stocked for 4 weeks and treated with low dose (3 g/kg/day) and high dose (6 g/kg/day) of ground dried pawpaw seeds mixed with their feed. The obtained results showed that the pawpaw seeds induced permanent sterility in the high dose treated fish while the low dose treatment showed reversible results. The results also demonstrated that fish treated with high dose of pawpaw exhibited higher biochemical and physiological effects as: low meat quality, a progressive fall in erythrocyte (RBCs) count, hemoglobin (Hb) content and haematocrit values. Also the high dose revealed a significant increase in the leukocytes (WBCs) count, serum glucose, total protein, aspartate aminotransferase (AST), alanine aminotransferase (ALT), creatinine and uric acid levels. Moreover, serum total lipids revealed a significant decrease compared to control group. On the other hand, the low dose treatment revealed lower biochemical and physiological changes. Histological sections of testis showed disintegration of sperm cells and focal necrosis of seminefrous tubules in the high dose treated fish, hepato-pancreas and posterior kidney tissues also showed severe changes in high dose treated fish. Milder degenerative changes in some necrotic foci and slight changes in hepato-pancreas and posterior kidney were observed in the low dose treated fish. The study concluded that pawpaw seeds which are cheap and easy to obtain, can be incorporated into fish feeds with adjusted amount and be used to control breeding of tilapia fish in growing ponds instead of unfavorable and expensive hormonal use.  相似文献   
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Paracetamol was administered at dosages of 5 mg/kg to camels and 10 mg/kg to goats by the intravenous and intramuscular routes. Parent paracetamol had a significantly slower clearance (21.9 ± 1.4 mL/min.kg vs. 52.8 ± 7.3 mL/min.kg) (P < 0.01) in camels than in goats. In camels the predominant metabolite in plasma was the sulphate, although the ratios of glucuronide:paracetamol and sulphate:paracetamol were similar (5.20 ± 0.50 vs. 6.59 ± 0.51) following intravenous administration. In goats the glucuronide metabolite was the predominant moiety in plasma, and the area under the curve (AUC) of the sulphate was only 3.89% of that of the glucuronide conjugate. The apparent AUC for paracetamol in the camel following intramuscular administration was larger than that following intravenous administration, however, when the bioavailability (F) was determined, with correction for altered half-life, within the animal and between study phases it was 71 ± 17% in goats and 105 ± 26% in camels.  相似文献   
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哈萨克族的草原游牧文化(Ⅱ)——哈萨克族的游牧生产   总被引:1,自引:1,他引:0  
哈萨克族是世界上最喜欢牲畜和善于饲养牲畜的民族之一。创造了一整套与自然环境相适应的生存技能,使得自然环境始终保持一种良好的存在状态。哈萨克族游牧文化的生产、生活方式及技能是以自然的适应作为前提条件。其实质造就了游牧文化中的物质生产的特征,进而决定了整个生产、生活方式的某些基本特征。如游牧生产具有游移性、实用性、简约性、稳定性;有适应游牧的家畜;有与环境相适应的生活用品,如适应游牧的衣物、食品、毡房等;在畜牧生产中有四季草地的利用标准;畜群结构的控制;转场中的环保习俗;狩猎中的习俗等。哈萨克族有适应游牧生活的独特的民族手工艺产业。  相似文献   
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研究哈萨克族的游牧文化对保护西北草原生态环境、巩固民族团结、促进少数民族地区经济发展和中华民族和谐统一具有十分重要的意义。哈萨克族是由古代许多部落和部族不断分化并逐步融合而成的,最主要的族源应是6世纪出现在汉文史籍中的"可萨",塞种、乌孙、匈奴、康居、可萨和突厥等是哈萨克族较早的民族源流。哈萨克语属阿尔泰语系突厥语族克普恰克语支,保留了丰富的古代突厥语词汇。哈萨克分布在世界40多个国家和地区,但至今没有任何方言。中国的哈萨克族主要分布在新疆北疆地区,且甘肃、青海都有分布。哈萨克先民曾使用过回鹘文等多种文字,现使用以阿拉伯字母为基础的拼音文字。历史上哈萨克族信仰过拜物教、萨满教、佛教、景教,最后信奉的是伊斯兰教,接受了伊斯兰文化。  相似文献   
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哈萨克族人民在生产生活中创造了丰富多彩的文化艺术。哈萨克文学包括书面文学和口头文学。主要代表作品有英雄史诗《阿里帕米斯》、《豁布兰德》、《叶尔塔尔根》、《哈木巴尔》、《哈班拜》等;爱情长诗如《吉别克姑娘》、《豁孜阔尔佩席与色彦苏鲁》、《恩利克与科别克》和《萨里哈与萨曼》等;叙事长诗有《考孜库尔帕西与巴彦苏鲁》、《克里米...  相似文献   
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