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101.
Abstract. The troglobitic cockroach, Trogoblattella chapmani , sp.n., is described. The genus was known previously from a single species found in limestone caves in Australia. Two of three other species found in the Sarawak caves, namely Symploce cavemicola (Shelford) and Pycnoscelus striata (Kirby) have previously been reported from cave habitats. The third, Pycnoscelus indicus (Fabricius), may have been reported previously from caves, under the name of Pycnoscelus surinamensis (Linnaeus). A single undetermined female of Blattella was present in the collection.  相似文献   
102.
ABSTRACT. Rules of zoological nomenclature, morphological data, and robosomal DNA sequence data support the validity of the genus Nucleospora , and its placement in the family Enterocytozoonidae. Although Nucleospora exhibits most of the distinguishing morophological characteristics of the family Enterocytozoonidae Cali and Owne, 1990, the distinctively different hosts (fish and humans, respectively) and sites of development (the nuclei of immature blood cells and the cytoplasm of enterocutes) supprot the placement Nucleospora and Enterocytozoon into separate genera. Ribosomal DNA sequence comparisons between Nucleospora salmonis and Enterocytozoon bieneusi showed 19.8% genetic divergece in the large and small subunit regions. Although more inter- and intrageneric divergence between the two species is sufficiently larg to deter suppression of the genus Nucleospora as a junior synonym of Enterocytozoon. A polymerase chain reaction test for the detection of N. salmonis in chinook salmon ( Oncorhynchus tshawytscha ), based on N. salmonis -specific ribosomal DNA sequence, is described.  相似文献   
103.
Anti-malarial gamete antibodies prevent the fertilization of gametes in the mosquito midgut and prevent transmission of malaria. Recently, hybridoma cell lines secreting monoclonal antibodies (10G3 and 11C7) against gametes of the malarial parasite have been developed. These antibodies act synergistically to mediate 80–90% suppression of the infectivity of gametocytes, although neither monoclonal antibody alone has a significant effect on gametocyte infectivity. We performed immuno-electron microscopy to characterize the interactions of these monoclonal antibodies with gametes of Plasmodium gallinaceum. Male gametes exposed to either 10G3 or 11C7 agglutinated into loose clusters, while those exposed to a mixture of 10G3 and 11C7 agglutinated into long, rope-like bundles. This difference appears to be related to the distribution of the antibodies on the surface of the gametes. When 10G3 or 11C7 labeled with a ferritin-conjugated anti-mouse Ig were used singly, the ferritin particles were distributed in focal areas over the surface of the parasites. By contrast, when the male gametes were exposed to a mixture of 10G3 and 11C7, the ferritin particles were distributed over their entire surface. Female gametes reacted similarly to these antibodies. These observations indicate that combinations of antibody specificities that reduce fertilization efficiency coat the entire surface of the gametes. On the other hand, focal interactions resulting from a single antibody are unable to block fertilization.  相似文献   
104.
105.
ABSTRACT. The ATP analogues adenylylimidodiphosphate and adenylylmethylenediphosphate are 3–5-fold more effective than ATP as gorging stimulants for Aedes aegypti. This increased potency is not due to the fact that the two analogues are not hydrolysed by the mosquito salivary apyrase, but most likely to their greater affinity to the mosquito gustatory receptor protein. The analogues 2'd ATP and 3'd ATP are about half as potent as ATP, while 2',3'-dideoxyadenosine triphosphate is 10-fold more potent than ATP in evoking the gorging response. It is proposed that removal of both hydroxyl groups eliminates binding of the stimulant at the ribose moiety, thus allowing the molecule greater freedom to rotate and bind more effectively to its two other binding sites at the amino group on the purine and at the terminal phosphate. Our data demonstrate that ATP activates the gorging response of Ae.aegypti merely by binding to its receptor protein and is not required as an exogenous source of energy. Gorging response to ATP is competitively inhibited by novobiocin.  相似文献   
106.
107.
The development of an expressed sequence tag (EST) collection for the poplar pathogen Septoria musiva presented an opportunity for the development of locus‐specific polymorphic markers. Five microsatellites simple sequence repeat (SSR) and six polymerase chain reaction (PCR)–restriction fragment length polymorphism (RFLP) markers were identified and tested on three S. musiva populations collected in the north‐central and northeastern regions of North America. The results obtained support previously published random amplified polymorphic DNA (RAPD) data.  相似文献   
108.
The Malagasy big‐headed turtle (Erymnochelys madagascariensis) is the only Erymnochelys species living in lakes, rivers and watersheds of western Madagascar. This species is endangered due to over harvesting of natural populations for human consumption. Eleven nuclear microsatellite loci were isolated from a genomic DNA library derived from a free‐ranging Malagasy big‐headed turtle from the Beroboka Classified Forest, Madagascar. Population genetic parameters were estimated on 10 individuals sampled from Ampijoroa and Andranohobaka River, Madagascar, to determine marker utility and as preliminary baseline values to study future populations in these locations.  相似文献   
109.
Nine microsatellite loci were isolated from a genomic DNA library created from impala (Aepyceros melampus). Observed and expected levels of heterozygosity were computed utilizing 25 individuals from a population in central Kenya. Tests for Hardy–Weinberg equilibria were conducted and found that three of the nine loci deviated from equilibrium in this population. These markers were developed to analyse the genetic effects of culling and isolation on a game preserve in Kenya.  相似文献   
110.
In this paper, we reassess the status of the two genera of scaled Entomobryinae with dental spines (Acanthocyrtus and Acanthurella) and we erect a new genus ( Sinhomidia ) on the basis of scale morphology and scale distribution. Scales are partially pointed in Acanthocyrtus and all rounded in Acanthurella. The new genus, Sinhomidia , has pointed scales, but lacks dental scales contrary to Acanthurella and Acanthocyrtus; in addition, it exhibits a unique dorsal macrochaetotaxy. Three new species of Acanthocyrtus are described ( Acanthocyrtus yolngui sp. nov. , Acanthocyrtus loftyensis sp. nov. , Acanthocyrtus barrowensis sp. nov. ) and two are redescribed [Acanthocyrtus spinosus (Schött, 1917), Acanthocyrtus lineatus Womersley, 1934]. One species (Acanthocyrtus bicolor Yosii, 1965 ) of the genus is redescribed and transferred to the new genus Sinhomidia . A key to the scaled Entomobryinae genera with dental spines and a key to the eight known Acanthocyrtus species are provided. © 2009 The Linnean Society of London, Zoological Journal of the Linnean Society, 2009, 157 , 495–514.  相似文献   
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