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1.
海洋生物活性肽研究进展   总被引:4,自引:0,他引:4  
综述几种海洋天然生物活性肽的研究进展,阐明酶解生物活性肽的理论基础和海洋生物活性肽的吸收理论。对活性肽在养殖业中的作用、当前海洋生物活性肽研究的不足及研究前景作了评述。  相似文献   

2.
海洋生物活性肽是海洋生物免疫系统长期进化而来的一类蛋白类分子,在宿主防御系统中起重要作用。大部分海洋生物活性肽可与细胞膜结合,起到抑制或杀死细菌、真菌、肿瘤细胞和病毒的作用。因其具有功能多样、来源广泛、特异性强、毒副作用小等优势,成为当今医药界的研究热点。本文主要综述了近年来有关海洋生物活性肽的发现、分类、提取及其抑菌机制的研究进展,为海洋生物活性肽类药物的进一步研究奠定基础。  相似文献   

3.
海洋生物活性提取物在化妆品中的应用   总被引:1,自引:0,他引:1  
从皮肤组织、衰老机理等多个方面阐述了海洋生物活性提取物的性能。揭示了海洋活性肽、海藻糖在抗氧化、抗辐射、护肤润肤、保湿等方面表现出的良好活性,以及其在新型抗衰老化妆品开发应用上所具有的潜力。并提示随着科学技术的不断发展,海洋生物活性提取物必将成为现代功效型化妆品的理想添加剂。  相似文献   

4.
生物活性肽及其研究进展   总被引:6,自引:0,他引:6  
生物活性肽来源广泛,目前已成为世界范围内的研究热点。生物活性肽具有显著的生理功能,如神经调节、激素作用、免疫调节、抗血栓、抗高血压、降胆固醇、抑菌、抗病毒、抗癌、抗氧化作用等,被誉为21世纪人类健康的新宠儿。本文综述了生物活性肽的种类、生理功能、吸收、制备、分离及研究进展,以期为生物活性肽的进一步研究和应用提供参考。  相似文献   

5.
生物活性肽是一类天然存在于动、植物和微生物等生物体内,或动、植物蛋白质经蛋白酶酶解以及人工化学合成或生物工程方法而得,且具有特殊生理活性的生物物质,具有较显著的抗肿瘤作用。此文介绍了生物活性肽的分类与特性、抗肿瘤作用,并简述了生物活性肽增强机体特异性和非特异性免疫功能、抗自由基与辐射损伤、诱导肿瘤细胞凋亡和直接作用于肿瘤细胞等多种作用机理,并简述了生物活性肽实现抗癌以及临床抗肿瘤药用等内容。  相似文献   

6.
海洋生物来源的多肽,种类丰富,结构新颖,副作用小,是近年来研究的热点。本文主要对海洋生物来源的具有血管紧张素转化酶(ACE)抑制、抗氧化、抗菌、抗肿瘤和多功能活性肽进行综述,并对多肽的提取分离方法进行介绍,为进一步研究海洋生物活性肽提供参考。  相似文献   

7.
海洋生物活性多糖的研究进展   总被引:1,自引:0,他引:1  
刘莺  刘新  牛筛龙 《医药导报》2006,25(10):1044-1046
随着海洋生物活性的研究进展,人类在海洋生物开发研究方面取得很大成就。多糖是海洋生物活性物质,研究表明具有多种生物活性和药用作用,如抗肿瘤、抗病毒、抗心血管疾病、抗氧化和免疫调节等。  相似文献   

8.
《中国海洋药物》2010,29(6):56-63
溴酚化合物广泛存在于多种海洋生物体内,它们具有酶抑制、抗氧化、抗炎、抗微生物和细胞毒等诸多生物活性,现概述海洋溴酚类化合物的结构特征、生物来源、生物活性等,以期为海洋溴酚类化合物的深入研究开发提供参考。  相似文献   

9.
张叶  雷虹 《北方药学》2012,9(1):32-33
随着人们生活水平的提高,伴随现代文明而来的各种富裕病如高血压、高血脂、肥胖病、癌症等越来越引起人们的关注,人们的消费观念已从单纯的吃饱吃好向防病治病方向转变.生物活性肽来源很广,目前已经成为世界范围内研究的热点.大量研究已表明,生物活性肽具有多种药理活性,如神经、激素和免疫调节、抗血栓、抗高血压、抗胆固醇、抗细菌病毒、抗癌作用等,是筛选药物的天然药物宝库.本文综述了生物活性肽的药理活性的研究进展.  相似文献   

10.
功能肽是指具有特异性生理活性或对生命活动有保护作用的复合肽类物质,又称生物活性肽。牡蛎中含有大量蛋白质,可以作为生物活性肽开发的优质材料,具有巨大的功能性食品潜力,在制药和医疗行业具有很大的应用价值。伴随着现代生物医药科技的革新,牡蛎肽萃取方法学的创新发展,牡蛎肽的生物活性和吸收率不断提高,使得对牡蛎肽生物学功能的认识不断深入,同时为其广泛应用提供了更加广阔的前景。概述牡蛎肽多样化活性的相关研究,为牡蛎肽的进一步发展应用提供新的线索和方向。  相似文献   

11.
Zinc: a multipurpose trace element   总被引:4,自引:2,他引:2  
Zinc (Zn) is one of the most important trace elements in the body and it is essential as a catalytic, structural and regulatory ion. It is involved in homeostasis, in immune responses, in oxidative stress, in apoptosis and in ageing. Zinc-binding proteins (metallothioneins, MTs), are protective in situations of stress and in situations of exposure to toxic metals, infections and low Zn nutrition. Metallothioneins play a key role in Zn-related cell homeostasis due to their high affinity for Zn, which is in turn relevant against oxidative stress and immune responses, including natural killer (NK) cell activity and ageing, since NK activity and Zn ion bioavailability decrease in ageing. Physiological supplementation of Zn in ageing and in age-related degenerative diseases corrects immune defects, reduces infection relapse and prevents ageing. Zinc is not stored in the body and excess intakes result in reduced absorption and increased excretion. Nevertheless, there are cases of acute and chronic Zn poisoning.  相似文献   

12.
Concern has been raised that selenium contamination may be adversely affecting endangered fish in the upper Colorado River basin. The objective of the study was to determine if operation of a water control structure (opened in December 1996) that allowed the Colorado River to flow through a channel area at Walter Walker State Wildlife Area (WWSWA) would reduce selenium and other inorganic elements in water, sediment, aquatic invertebrates, and forage fish. Endangered Colorado pikeminnow were collected and muscle plug samples taken for selenium analysis. Selenium concentrations in filtered water were 21.0 microg/L in 1995, 23.5 microg/L in 1996, 2.1 microg/L in 1997, and 2.1 microg/L in 1998. Selenium concentrations in sediment cores and sediment traps were 8.5 microg/g in 1995, 8.2 microg/g in 1996, 4.8 microg/g in 1997, and 1.1 microg/g in 1998. Selenium concentrations in aquatic invertebrates were 27.4 microg/g in 1996, 15.5 microg/g in 1997, and 4.9 microg/g in 1998. Selenium concentrations in forage fish were 27.2 microg/g in 1996, 20.2 microg/g in 1997, and 8.6 microg/g in 1998. Selenium concentrations in muscle plugs of Colorado pikeminnow were 9.8 microg/g in 1995, 9.5 microg/g in 1996, 9.0 microg/g in 1997, and 10.3 microg/g in 1998. Although selenium concentrations in water, sediment, aquatic invertebrates, and forage fish decreased substantially after operation of the water control structure, a corresponding change in Colorado pikeminnow did not seem to occur. Selenium concentrations in muscle plugs decreased with increasing fish total length and weight, did not change between repeat sampling in the same year or recapture in subsequent years, and seemed to be most closely associated with the mean monthly river flow for the March-July period.  相似文献   

13.
The objective of this review is to provide a report on toxic plants causing reproductive problems in ruminants in Brazil. Aspidosperma pyrifolium causes abortion or stillbirth in goats, as well as most likely in sheep and cattle, in the semiarid regions of Northeastern Brazil. Intoxications by Ateleia glazioveana, Tetrapterys acutifolia and T. multiglandulosa result in abortion and neonatal mortality in cattle and sheep, and the same signs have been experimentally observed in goats. These three plants can also cause cardiac fibrosis and a nervous disease with spongiosis of the central nervous system. Other plants known to cause abortion include Enterolobium contortisiliquum, E. gummiferum, Stryphnodendron coriaceum, S. obovatum and S. fissuratum. These plants can also cause digestive signs and photosensitization. Abortions have been reported in animals intoxicated by nitrates and nitrites as well. Infertility, abortions and the birth of weak offspring have been reported in animals intoxicated by plants containing swainsonine, including Ipomoea spp., Turbina cordata and Sida carpinifolia. Trifolium subterraneum causes estrogenism in cattle. Mimosa tenuiflora and, most likely, M. ophthalmocentra cause malformations and embryonic mortality in goats, sheep and cattle in the semiarid regions of Northeastern Brazil.  相似文献   

14.
Chronic inhalation of 2-butoxyethanol resulted in an increase in liver hemangiosarcomas and hepatic carcinomas in male mouse liver. No increase in liver neoplasia was observed in similarly exposed male and female rats or female mice. We proposed that the production of liver neoplasia in the male mouse is the result of oxidative damage secondary to the hemolytic deposition of iron in the liver. This occurs selectively in the male mouse and leads either directly or indirectly to liver neoplasia. To address this proposal, male B6C3F1 mice and male F344 rats were treated with 2-butoxyethanol (via daily gavage; five times per week) at doses of 0, 225, 450, and 900 mg/kg/day (mice) and 0, 225, and 450 mg/kg/day (rats) respectively. Following treatment for 7, 14, 28, and 90 days, DNA synthesis, oxidative damage, hematocrit, and iron deposition were measured in the livers. An increase in hemolysis (measured by a decrease in hematocrit and increase in relative spleen weight) was observed in 2-butoxyethanol-treated rats and mice in a dose-dependent manner. An increase in the percentage of iron-stained Kupffer cells was observed following treatment with 450 and 900 mg/kg of 2-butoxyethanol in mice and 225 and 450 mg/kg of 2-butoxyethanol in rats. A biphasic increase in oxidative damage (8-hydroxydeoxyguanosine and malondialdehyde) was seen in mouse liver after 7 and 90 days of treatment with 2-butoxyethanol, whereas no increases were observed in treated rat liver. Vitamin E levels were reduced by 2-butoxyethanol treatment in both mice and rat liver; however, the basal level of vitamin E was approximately 2.5-fold higher in rat than in mouse liver. A similar biphasic induction of DNA synthesis was seen following 2-butoxyethanol treatment in the mouse. In the mouse liver, increased DNA synthesis was observed in hepatocytes at 90 days and in endothelial cells at 7 and 14 days at all doses. No change in DNA synthesis was seen in 2-butoxyethanol-treated rat liver. No apparent differences in apoptosis and mitosis in the liver were observed in mouse and rat liver between 2-butoxyethanol treatment groups and untreated controls. These results suggest that DNA synthesis, possibly from oxidative stress or Kupffer cell activation, occurs selectively in the mouse liver, primarily in endothelial cells (a target of 2-butoxyethanol neoplasia), following exposure to 2-butoxyethanol.  相似文献   

15.
Tert-butyl hydroperoxide (TBHP) is a catalyst frequently used in oxidation and sulfonation reactions in the plastics industry. Since the toxicological evaluation of TBHP remains unknown, the National Toxicology Program (NTP) designed studies to characterize and compare TBHP toxicity by the dermal and oral (gavage) routes in male and female Fischer 344 rats and B6C3F1 mice in 14-day exposures. Rats and mice were administered TBHP at 22, 44, 88, 176 or 352 mg/kg in 0.5% aqueous methylcellulose for the gavage studies. In the dermal studies, mice were administered the same doses as above, while rats were administered four doses (22, 44, 88, 176 mg/kg) in 50% aqueous acetone. Results from the gavage studies revealed treatment-related decreases in survival in male rats and body weights in both male and female rats in the 352 mg/kg group. Clinical signs included post-treatment lethargy, thinness, abnormal breathing, ruffled fur, and/or ataxia which occurred sporadically. The male mice showed a statistically significant decrease in body weight in the 44, 88, 176, and 352 mg/kg groups. The major target organs of toxicity were the forestomach in male and female rats and mice, and the esophagus in male and female rats and in male mice. In addition, there was an increase in the absolute and relative liver weight in female mice with hepatocellular hypertrophy in the top-dose group only. Results from spin trapping experiments revealed the presence of electron paramagnetic resonance signals from radical adducts in the blood and organic extracts of the liver and kidneys of rats treated by gavage with 176 mg/kg TBHP, suggesting the involvement of free- radical generation. The no observed adverse effect level (NOAEL) was considered to be 22 mg/kg in rats and male mice, and 44 mg/kg in female mice. In the dermal studies, there was no effect on survival, body weight, or organ weights in either rats or mice. TBHP administration at the site of application resulted in dermal irritation, hyperkeratosis, hyperplasia, and/or inflammation of the epidermis and inflammation of the dermis at 176 mg/kg and above in male and female rats. Dermal irritation at the site of application was noted in all the mice exposed to 352 mg/kg TBHP. Histopathological lesions in the epidermis and dermis were seen in the 88–352 mg/kg males and in the 176–352 mg/kg females. The NOAEL was found to be 88 mg/kg for male rats and female mice, and 44 mg/kg for female rats and male mice. In conclusion, these studies demonstrate that TBHP is metabolized to free radicals and is a contact irritant affecting skin by the dermal route of exposure, and forestomach and esophagus by oral administration. There was no evidence of systemic absorption by the dermal route of exposure based on lack of pathological findings (Supported by National Institute of Environmental Health Sciences Contract No. N01-ES-65406).  相似文献   

16.
This study examined the potential adverse effects of the subacute exposure of rats to concrete and hwangto building environments. Polycarbonate was used as a comparison. Groups of 10 male rats were exposed to polycarbonate, concrete, or hwangto cages for a 4-week period in summer or winter. During the study period, the clinical signs, mortality, skin temperature, body weight, food consumption, ophthalmoscopy, urinalysis, hematology, serum biochemistry, gross findings, organ weights, and histopathology were examined. The concentration of total volatile organic compounds (VOCs), temperature, and relative humidity in the each cages were also measured. There were no exposure-related effects in any group of the study examined in the summer. The temperature, relative humidity, and the concentration of VOCs in the cages were similar in all groups. However, in the winter study, significant differences in several parameters were detected among the groups. In the concrete group, there was an increase in the clinical signs, a reduction in the body weight gain, food intake, and liver weight, an increase in the lung weight, and an increase in the histopathological alterations in the lung and thymus. Infrared thermal analysis showed that the skin temperature of the rats in the concrete group was lower than that in the polycarbonate group. However, in the hwangto group, there was a decrease in the clinical signs and an increase in the body weight, food intake, and the weights of the heart, lung, spleen, and epididymides. Overall, the 4-week exposure of the rats to the concrete building environment had adverse effects on the clinical signs, skin temperature, body weight, and some organs in the winter but not in the summer. On the other hand, the exposure of hwangto building environment did not have any exposure-related adverse effects on the general health parameters and skin temperature in rats.  相似文献   

17.
目的 观察维生素E联合川芎嗪对幼鼠视网膜缺血再灌注及其外周血氧化相关物质的影响,探讨其对损伤后保护的作用机制.方法 选取清洁级3周龄幼鼠100只,随机分为5组,每组20只.A组为假造模组、B组为模型组、C组为维生素E干预组、D组为川芎嗪干预组、E组为维生素E联合川芎嗪干预组,再灌注损伤后4h处死幼鼠,检测外周血清谷胱甘肽过氧化物酶(glutathione peroxidase,GSH-PX)、超氧化物歧化酶(superioxide dismutase,SOD)、活性氧类物质(reactive oxygen species,ROS)、丙二醛(malondialdehyde,MDA),用Tunel染色法检测视网膜细胞凋亡情况.结果 幼鼠眼球视网膜细胞Tunel指数B组高于其他4组,E组低于C、D组,D组低于C组(P<0.05).Tunel染色阳性集中在细胞核部位,表现为细胞核固缩.GSH-PX、SOD活性B、C、D、E组均低于A组,C、D、E组高于B组,D、E组高于C组,E组高于D组(P<0.05);B、C、D、E组ROS活性和MDA含量均高于A组,C、D、E组均低于B组,且D、E组低于C组,E组低于D组(P<0.05).结论 维生素E联合川芎嗪能通过抑制凋亡与抗氧化对缺血再灌注视网膜起到很好的保护作用,两药联合应用效果更佳.  相似文献   

18.
目的 调查两组相隔7年的鲍曼不动杆菌菌株可能存在的耐药基因状况及菌株间的亲缘关系。方法 分别收集南京医科大学附属淮安第一医院2008年20株鲍曼不动杆菌,2016年20株鲍曼不动杆菌。菌种鉴定为鲍曼不动杆菌种特异mdfA基因与blaOXA-51基因PCR双重检测为阳性方确认为鲍曼不动杆菌。再用PCR方法检测32种β-内酰胺类药物获得性耐药基因、15种氨基糖苷类药物获得性耐药基因、10种可移动遗传元件遗传标记,最后对检测结果作样本聚类分析(UPGMA法)。 结果 2016年分离株对第三代头孢类药物、碳青霉烯类药物、氨基糖苷类药物、喹诺酮药物均为耐药。2008年分离株仅对第三代头孢类药物均为耐药,而对碳青霉烯类药物均为敏感,对喹诺酮药物、氨基糖苷类药物分别有50.00%和60.00%的敏感性。2008和2016年分离株均检出blaADC和blaOXA-51,但blaOXA-2群、blaOXA-23群只有2016年分离株均被检出。2008年分离株对第三代头孢类药物耐药主要与blaADC相关,2016年分离株对第三代头孢类药物、碳青霉烯类药物耐药主要与blaADC、blaOXA-2群和blaOXA-23群相关。2016年分离株均测出aac(2)-Ⅰb、aph(3)-Ⅰ、armA等3种氨基糖苷类药物耐药相关基因,而2008年分离株均无检出。可移动遗传元件遗传标记tnpU、tnp513、IS26和ISaba1等4种也只有2016年分离株被全部检出。菌株亲缘关系分析可见2008和2016年不同年份分离株分成两个独立的簇群(A簇群和B簇群),2016年分离株聚集性更强相差系数更小。A和B簇群均可分为两个亚簇群。A-1亚簇群有两个克隆播散,A-2、B-1和B2亚簇群各有一个克隆播散。其中2016年分离株B-簇群一个有14株菌构成的大克隆播散。分离株耐药元件检测阳性模式显示,2008年分离株仅携带2~7种耐药元件基因;2016年分离株则携带14种~16种耐药元件基因。结论 多种β-内酰胺类药物耐药基因、氨基糖苷类药物耐药基因和可移动遗传元件是导致鲍曼不动杆菌对抗菌药物耐药的重要原因。在同一家医院的对相隔7年的鲍曼不动杆菌临床分离株进行耐药元件基因检测与分析是国内首次报道。不同年份分离株的耐药性和耐药元件基因携带状况差异明显:2016年分离株比2008年分离株耐药性更强,携带的耐药元件基因更多。2008年和2016年分离株均有克隆播散,提示有医院感染的存在。  相似文献   

19.
目的探讨糖尿病性偏侧舞蹈症的临床特点、发病机制、影像学改变及预后,防止误诊及漏诊。方法回顾性分析10例糖尿病性偏侧舞蹈症的临床症状、影像学变化、实验室检查结果和治疗经过,并复习相关文献。结果①10例均为未经治疗的糖尿病患者,其中6例为糖尿病非酮症高血糖症,4例为酮症高血糖症。②临床表现;7例为突发起病并以一侧肢体为主的持续性舞蹈样运动,3例为发作性口角抽动伴单肢不自主舞动起病。症状均清醒时出现,睡眠时消失。肌力均为5级,肌张力均正常。③影像学表现:早期CT表现为舞蹈症状对侧的尾状核、壳核和(或)苍白球,丘脑的高密度影像,内囊未受累,并在1个月左右减弱或消失;磁共振(MRI) T_1像为病灶部位的片状高信号,在持续数月后信号减低,T_2则表现为稍低信号或病灶部位区域中心混杂信号而周边高信号,边界清晰,无明显水肿征象。④本组患者均给予氟哌啶醇及氯硝安定等药物治疗并控制血糖,症状均在短期内迅速改善。结论糖尿病性偏侧舞蹈症多见于血糖控制不佳的糖尿病患者,结合特定部位的变化性磁共振成像及肢体舞蹈样动作可以做出诊断。在控制血糖的基础上,应用氟哌啶醇和氯硝安定治疗效果较好。  相似文献   

20.
Maintenance of bile acid (BA) homeostasis is essential to achieve their physiologic functions and avoid their toxic effects. The marked differences in BA composition between preclinical safety models and humans may play a major role in the poor prediction of drug‐induced liver injury using preclinical models. We compared the composition of plasma and urinary BAs and their metabolites between humans and several animal species. Total BA pools and their composition varied widely among different species. Highest sulfation of BAs was observed in human and chimpanzee. Glycine amidation was predominant in human, minipig, hamster and rabbit, while taurine amidation was predominant in mice, rat and dogs. BA profiles consisted primarily of tri‐OH BAs in hamster, rat, dog and mice, di‐OH BAs in human, rabbit and minipig, and mono‐OH BA in chimpanzee. BA profiles comprised primarily hydrophilic and less toxic BAs in mice, rat, pig and hamster, while it primarily comprised hydrophobic and more toxic BAs in human, rabbit and chimpanzee. Therefore, the hydrophobicity index was lowest in minipig and mice, while it was highest in rabbit, monkey and human. Glucuronidation and glutathione conjugation were low in all species across all BAs. Total concentration of BAs in urine was up to 10× higher and more hydrophilic than plasma in most species. This was due to the presence of more tri‐OH, amidated, sulfated and primary BAs, in urine compared to plasma. In general, BA profiles of chimpanzee and monkeys were most similar to human, while minipig, rat and mice were most dissimilar to human.  相似文献   

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