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1.
2.
Total global biodiversity is estimated at between 3 and 500 × 106 species of prokaryote and eukaryote organisms spread across 70 or more phyla. The marine macrofauna alone are estimated between 0.5 and 30 × 106 species and represents a broader range of taxonomic diversity than that found in the terrestrial environment, which has been the traditional source of natural products. With a typical eukaryote possessing 50,000 genes, the global marine macrofauna are the source of 2.5 × 1010 to 1.5 × 1012 primary products and an associated extensive range of secondary products. However, only a few thousand novel compounds from marine organisms have been described. These compounds have proven unique in chemical and pharmacological terms but, as yet, no therapeutic agents have resulted. Given a broader drug discovery strategy, and facilitated by technological advances, it is predicted that the characterisation of marine chemical diversity will be accelerated. Strategies for drug discovery from the virtually untapped chemical diversity of marine organisms are discussed. © 1994 Wiley-Less, Inc. 相似文献
3.
一些损伤和疾病平时罕见,特殊情况下可以发生,造成严重危害。特殊情况主要包括严重事故、灾害、战争、恐怖主义活动以及特殊环境与特殊作业的危害等。本阐述了现代战争中发生的贫铀武器伤害、燃料空气炸弹伤害、微波武器伤害和战时精神疾病;可能源于恐怖主义活动的炭疽、天花;严重事故性伤害中的核事故、化学事故和煤矿事故伤害;严重灾害中的地震、海难(海战)落海伤害。中介绍了这些伤病的发生情况、伤害特点与医学救治。 相似文献
4.
Acute nonlymphatic leukemia among deck officers on coastal tankers: a report of two cases 总被引:2,自引:0,他引:2
Ralph I. Nilsson Jan Carneskog Bengt G. Jrvholm Rolf G. Nordlinder 《American journal of industrial medicine》1988,14(6):657-659
Deck officers on coastal tankers may be exposed to high concentrations of cargo vapors during loading and tank-cleaning operations. Two cases of acute nonlymphatic leukemia are described. Both men had worked as chief officers on coastal tankers transporting benzene and other petroleum products. 相似文献
5.
Chia-Ying Liu Chih-Cheng Lai Hsiu-Tzy Chiang Min-Chi Lu Ling-Fang Wang Tsai-Ling Tsai Mei-Yu Kang Yi-Ni Jan Yi-Ting Lo Wen-Chien Ko Shu-Hui Tseng Chun-Ming Lee Po-Ren Hsueh 《Journal of microbiology, immunology, and infection》2019,52(1):62-74
Background/purpose
This study investigated the distribution and persistence of multidrug resistant organisms (MDROs) including methicillin-resistant Staphylococcus aureus (MRSA), carbapenem-resistant Enterobacteriaceae (CRE), carbapenem-resistant Pseudomonas aeruginosa (CRPA), and multidrug-resistant Acinetobacter baumannii (MDRAB) in six long-term care facilities (LTCFs).Methods
We investigated the distribution of MDROs in residents of six LTCFs and their environments from January to December 2016 (intervention period). Active surveillance of colonization of MDROs was performed by culturing rectal and nasal swab samples from the residents every three months. Multilocus sequence typing (MLST) was conducted, and genes for panton-valentine leukocidin (PVL) from MRSA isolates were determined.Results
A total of 521 samples were positive for MDROs, and MRSA was the most common organism (65.1%), followed by MDRAB (11.3%), carbapenem-resistant Klebsiella pneumoniae (11.1%), carbapenem-resistant Escherichia coli (4.6%), and carbapenem-resistant P. aeruginosa (2.1%, n = 11). By a linear regression model, positive MRSA isolates from the environment were found to be statistically significant and associated with the number of colonized LTCF residents (p = 0.01), while the timing of the surveillance culture was not (p = 0.227). The main MLST types associated with PVL-production were sequence type (ST) 59, (40.0%, 24/60), ST30 (21.4%, 3/14), ST8 (87.5%, 14/16), and ST45 (3.6%, 1/28). The susceptibility rates of tetracycline (96.7%), trimethoprim-sulfamethoxazole (96.7%), and ciprofloxacin (81.7%) were statistically significant and higher in MRSA ST59, compared to the rates in MRSA ST45 isolates.Conclusions
MRSA was the most commonly colonized MDRO, both in the LTCF residents and in the environment, followed by MDRAB and carbapenem-resistant K. pneumoniae. 相似文献6.
Ultrastructural analysis of pancreatic acinar cells from mice fed on genetically modified soybean 下载免费PDF全文
Malatesta M Caporaloni C Rossi L Battistelli S Rocchi MB Tonucci F Gazzanelli G 《Journal of anatomy》2002,201(5):409-415
No direct evidence that genetically modified (GM) food may represent a possible danger for health has been reported so far; however, the scientific literature in this field is quite poor. Therefore, we investigated the possible effects of a diet containing GM soybean on mouse exocrine pancreas by means of ultrastructural, morphometrical and immunocytochemical analyses. Our observations demonstrate that, although no structural modification occurs in pancreatic acinar cells of mice fed on GM soybean, quantitative changes of some cellular constituents take place in comparison to control animals. In particular, a diet containing significant amount of GM food seems to influence the zymogen synthesis and processing. 相似文献
7.
Inactivation of viruses infecting ectothermic animals by amphibian and piscine antimicrobial peptides 总被引:7,自引:0,他引:7
The ability of five purified amphibian antimicrobial peptides (dermaseptin-1, temporin A, magainin I, and II, PGLa), crude peptide fractions isolated from the skin of Rana pipiens and R. catesbeiana, and four antimicrobial peptides (AMPs) from hybrid striped bass (piscidin-1N, -1H, -2, and -3) were examined for their ability to reduce the infectivity of channel catfish virus (CCV) and frog virus 3 (FV3). All compounds, with the exception of magainin I, markedly reduced the infectivity of CCV. In contrast to CCV, FV3 was 2- to 4-fold less sensitive to these agents. Similar to an earlier study employing two other amphibian peptides, the agents used here acted rapidly and over a wide, physiologically relevant, temperature range to reduce virus infectivity. These results extend our previous findings and strongly suggest that various amphibian and piscine AMPs may play important roles in protecting fish and amphibians from pathogenic viruses. 相似文献
8.
Viruses infecting algal hosts possess large double-stranded DNA as genomes. We have recently identified a family of viruses specific for filamentous brown algae. In contrast to the better known Chlorella viruses with their lytic infection cycle, marine brown algal viruses latently occur in their host cells and are induced to multiply in response to a variety of external stimuli such as change in light and temperature. Here, I summarize the known properties of this family of viruses and discuss their taxonomic classification. 相似文献
9.
František Moravec Sonia Ternengo Céline Levron 《Acta parasitologica / Witold Stefański Institute of Parasitology, Warszawa, Poland》2006,51(2):111-118
Gravid or subgravid females of the following three species belonging to the nematode genus Philometra were collected from marine perciform fishes of the Bonifacio Strait Marine Reserve, Corsica, France: Philometra justinei sp. nov. (prevalence 1.5%, intensity 11) and Philometra sp. (prevalence 3%, intensity 2) from the abdominal cavity and gonads, respectively, of the striped red mullet Mullus surmuletus (Mullidae), and Philometra serranellicabrillae Janiszewska, 1949 (prevalence 27%, intensity 2–6) from the gonads of the comber Serranus cabrilla (Serranidae). The newly described species, P. justinei, is mainly characterized by the absence of an anterior bulbous inflation of the oesophagus, body length of the gravid female
(196 mm), conspicuously large amphids, number and distribution of cephalic papillae, and the morphology of larvae. It is the
second known species of Philometra parasitizing fishes of the family Mullidae and the ninth species of this genus reported from marine fishes of the Mediterranean
region. P. serranellicabrillae, studied for the first time by SEM, is redescribed. 相似文献
10.
目的 探讨糖尿病足患者发生多重耐药菌(MDROs)感染的危险因素及病原菌分布情况。方法 以2019年1月至2020年12月青岛市某三甲医院内分泌门诊就诊的糖尿病足患者为研究对象进行资料收集、体格检查及空腹静脉血采集,并采用灭菌棉拭子擦拭创面拭取分泌物用于病原菌感染情况及耐药性检测。采用描述流行病学分析方法进行分析,并采用单、多因素分析方法对多重耐药影响因素进行分析。结果 本研究共对5 122例糖尿病足患者进行MDROs感染情况分析,年龄35~85岁,平均(61.03±11.19)岁,糖尿病病程1~29年,平均(12.32±7.16)年。多重感染者210例,多重感染率为4.10%。共分离出265株MDROs,居于前3位的MDROs分别是金黄色葡萄球菌109株(41.13%)、铜绿假单胞菌61株(23.02%)、大肠杆菌58株(21.89%)。主要的MDROs中金黄色葡萄球菌对苯唑西林、氨苄西林/舒巴坦、头孢唑林100%耐药,大肠杆菌对氨苄西林、哌拉西林/他唑巴坦、头孢他啶100%耐药,未见对万古霉素耐药菌。多因素Logistic回归分析结果显示,抗菌药物暴露史(OR=1.962)、因同一伤口住院次数>2次/年(OR=1.970)、骨髓炎(OR=4.323)、神经缺血性伤口(OR=1.269)和抗菌药物疗程≥5 d(OR=1.487、3.274、1.602)是糖尿病足患者发生MDROs感染的危险因素。结论 糖尿病足患者抗菌药物暴露史、因同一伤口住院次数>2次/年、骨髓炎、神经缺血性伤口以及使用抗菌药物疗程与发生MDROs感染存在密切关系。 相似文献