ISSN:0022-3921    

DOI:10.1111/j.1550-7408.1981.tb02793.x

出版商:Blackwell Publishing Ltd    

年代:1981

数据来源: WILEY

摘要:

ABSTRACTAutecology (cellular organelles and secretions, encystment and dispersal abilities), environmental conditions (physiological tolerances and interaction with other organisms), and evolutionary history contribute to protist biogeography, which manifests ecological and historical aspects. Ecological biogeography is seen in the influence of geochemistry on the distribution of fresh‐water phytoflagellates and algae, and of moisture and vegetation type on soil‐litter protists. A temporal feature is often present because many protists encyst and respond only to certain ranges of temperature and organic content. Historical biogeography has occurred by radiative host evolution on symbiotic protozoa (e.g., termite flagellates and rumen ciliates), and by the isolating effects of water currents, temperature, and density gradients on oceanic protists (coccoliths, dinoflagellates, foraminifera, radiolaria, and tintinnines). These two aspects combine in protists living on animal surfaces. Humans affect protist biogeography by increasing parasite ranges through human migrations and by water pollution. They can diminish these situations by disease control and exploiting appropriate ciliates in sewage disposal. Many free‐living protozoa appear to be cosmopolitan, but mating types and isoenzyme studies suggest that speciation with its geographic connotations may be more widespread than presently apprec

ISSN:0022-3921    

DOI:10.1111/j.1550-7408.1981.tb02794.x

出版商:Blackwell Publishing Ltd    

年代:1981

数据来源: WILEY

ISSN:0022-3921    

DOI:10.1111/j.1550-7408.1981.tb02796.x

出版商:Blackwell Publishing Ltd    

年代:1981

数据来源: WILEY

摘要:

ABSTRACTThe use of drugs in domestic animals is dominated by considerations of cost‐effectiveness and profitability. They are extensively used against coccidial infections of poultry where they are an important factor in intensive husbandry. Ionophore antibiotics, which dominate this field, may have applications in ruminants. Imidocarb is of therapeutic and prophylactic value against babesial infections and there are new prospects for control of theileriasis. Effective drugs for the control of African trypanosomiasis are limited and attention is being given to alternative uses of available compound

ISSN:0022-3921    

DOI:10.1111/j.1550-7408.1981.tb02797.x

出版商:Blackwell Publishing Ltd    

年代:1981

数据来源: WILEY

摘要:

ABSTRACTPolyamines are multiply amine‐substituted straight‐chain aliphatics; their content in different tissues may vary widely, and their functions are many. Their main routes of biosynthesis originate from ornithine and methionine. Polyamine content and biosynthesis in tryposomatid flagellates are reviewed concluding with emphasis on their possible role as critical drug targets in these parasitic protozoa so pathogenic for man in large areas of the wo

ISSN:0022-3921    

DOI:10.1111/j.1550-7408.1981.tb02798.x

出版商:Blackwell Publishing Ltd    

年代:1981

数据来源: WILEY

摘要:

ABSTRACTAvailable evidence indicates that many of the antiprotozoal drugs currently in use significantly modify the immune response of the host. The effect depends on both the drug and the host. Some drugs enhance the immune response, some are immuno‐suppressants, and others enhance some types of immune mechanisms while suppressing others. Future efforts in the development of antiprotozoal drugs should consider their effects on both the parasite and the immune response of the host. Also in the chemotherapy of protozoal infections consideration should be given to the combined usage of immunoenhancing agents and antiprotozoal drug

ISSN:0022-3921    

DOI:10.1111/j.1550-7408.1981.tb02799.x

出版商:Blackwell Publishing Ltd    

年代:1981

数据来源: WILEY

摘要:

ABSTRACTAn assessment is given of the present state of the art in chemotherapy of protozoal infections with suggestions as to improved results in the future, especially by rendering available drugs more effective. Selective targeting of chemotherapeutic agents through enhancement of lysosomotropic character has been demonstrated, particularly through the use of liposome‐encapsulated drug

ISSN:0022-3921    

DOI:10.1111/j.1550-7408.1981.tb02800.x

出版商:Blackwell Publishing Ltd    

年代:1981

数据来源: WILEY

摘要:

ABSTRACTHistological examination of gills of the rock crab (Cancer irroratusSay, 1917) taken from specimens collected in polluted and nonpolluted areas indicated that gill discoloration was not directly related to the degree of microbial fouling. Light microscope studies demonstrated that bacteria, peritrich and suctorian ciliates, and some naviculoid diatoms were the principal members of the fouling community. Examination of the bacteria by electron microscopy showed that several distinct types were present, and that some of these were attached to the gill by holdfast structures while others were enmeshed in a filamentous slime layer. An unusual small marine flagellate and an unidentified amoeba were also examined ultrastructurally.

ISSN:0022-3921    

DOI:10.1111/j.1550-7408.1981.tb02801.x

出版商:Blackwell Publishing Ltd    

年代:1981

数据来源: WILEY

摘要:

ABSTRACTEight species of loricate choanoflagellates (Acanthoecidae),Acanthoecopsis spiculiferaNorris,Bicosta antennigeraMoestrup,Bicosta spiniferaThrondsen,Calliacantha multispinaManton&Oates,Calliacantha simplexManton&Oates,Crinolina apertaLeadbeater,Diaphanoeca multiannulatan. sp., andParvicorbicula socialis(Meunier) Deflandre, have been observed, by light and electron microscopy, in samples obtained from the Weddell Sea during the austral summer of 1977.Diaphanoeca multiannulatais described for the first time from these samples: the other organisms are discussed. The distribution of most species within the Weddell Sea was widespread. Habitats in which choanoflagellates were found included the water column, the edge of (or ponds on) ice floes, and the interior of ice floes. The distributional, environmental, habitat, and/or morphological range of all previously described species is expanded. Methods of variation of transverse costal diameters between genera may be potentially useful to the understanding of taxonomy and phylogeny of this family.

ISSN:0022-3921    

DOI:10.1111/j.1550-7408.1981.tb02802.x

出版商:Blackwell Publishing Ltd    

年代:1981

数据来源: WILEY

摘要:

ABSTRACTA survey of protozoa polluting bottled mineral water in Mexico was carried out using samples obtained from the three best‐selling brands of bottled mineral water in the country. The organisms were concentrated through filtration procedures and subsequently cultured in sterile media. The cultures were observed over four weeks, with identification to the level of genus and species. Most commonly found were the amoebaeNaegleria gruberi, Acanthamoeba astronyxis, andVahlkampfia vahlkampfi(trophic as well as cystic stages) plus one flagellate,Bodomorpha minima. No ciliates were detected. The public health importance of the findings is obvious, since some strains ofNaegleriaandAcanthamoebahave the potential to cause human disease that may lead to deat

ISSN:0022-3921    

DOI:10.1111/j.1550-7408.1981.tb02803.x

出版商:Blackwell Publishing Ltd    

年代:1981

数据来源: WILEY