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211.
ABSTRACT Many Korean entomologists have attempted to colonize Anopheles sinensis Korean strain, a primary malaria vector in Korea, previous efforts, however, were unsuccessful. Only a study that a successful colonization of An. sinensis Korean strain over 5 generations was recently reported. Recently we obtained a self-mating colony from this mosquito strain. The original colony was established from progenies obtained from females collected from So-Rae District, Incheon, Republic of Korea (ROK), and was maintained for 23 successive generations. While the adult females of first five generations were fed on humans as a source of blood, those of the subsequent 18 generations were fed on white rats as a source of blood. A self-mating colony was initiated from the 9th generation by rearing 200 and 300 newly emerged females and males, respectively, in a 30x30x30 cm cage. The insemination rates increased from approximately 40% to 81% by the 20th generation. Comparisons of biological aspects between artificial mating and self-mating colonies are reported.  相似文献   
212.
213.
Judges were required to rate the total intensity of NaCl solutions using a variety of unstructured category and line scales under a 'rank-rating' protocol and a traditional protocol that did not allow retasting or the reviewing of scores. The various scales and protocols induced two types of scaling errors. The first type was named a different-stimulus error. This involved a judge rating a stronger stimulus as equal to or less than a weaker stimulus. The second type was named a same-stimulus error. This involved a judge giving different ratings to two stimuli of equal concentration. For all scales, judges made a higher proportion of same-stimulus errors than different-stimulus errors. 'Rank-rating' only reduced the proportion of different-stimulus errors. It was hypothesized that a category scale with fewer categories would induce a higher level of different-stimulus errors but lower level of same-stimulus errors. These trends were noted but not always significantly. For line scales, the equivalent hypotheses regarding line length were either weak or not supported. It would appear that increasing the length of a line scale is not always equivalent to increasing the number of categories in a category scale.  相似文献   
214.
A taxonomic study of the subgenus Agathidium of the genus Agathidium Panzer in Korea is presented. Four species [Agathidium (Agathidium) coreanum Angelini, A. (A.) crassicorne Portevin, A. (A.) merkli Angelini, and A. (A.) oblongum Angelini] are recognized. Agathidium (A.) mequignoni Roubal recorded by Angelini is misidentification of A. (A.) crassicorne Portevin. Spermatheca of A. (A.) merkli is illustrated for the first time. A key to the species, diagnoses and illustrations of diagnostic characters are provided.  相似文献   
215.
This study was conducted to investigate effects of brain‐derived neurotrophic factor (BDNF) on the neurite growth of deutocerebral neurons in vitro, and production of BDNF‐like neuropeptide from brain of the silk moth, Bombyx mori. In primary culture of antennal lobe (AL) neurons with BDNF, it promoted a significant neurite extension of putative AL projection neurons and an outgrowth of branches from principal neurites of putative AL interneurons. Results from immunolabeling of brain and retrocerebral complex showed that BDNF ‐like neuropeptide labeled in brain was synthesized by median and lateral neurosecretory cells, then transported to corpora allata for storage.  相似文献   
216.
A taxonomic study of the genera Porocallus Sharp and Rhomphocallus Assing in Korea is presented. The genus Rhomphocallus and two species, Rhomphocallus princeps (Sharp) and Rhomphocallus maruyamai Assing, are reported for the first time in Korea. Porocallus insignis Sharp is recorded for the first time in South Korea. Diagnoses, illustrations of habitus and line drawings of diagnostic characters are provided.  相似文献   
217.
The dock plant (Rumex spp.) is one of the most problematic pasture weeds worldwide. Allantus luctifer was selected as a potential biological control agent for Rumex spp. Continuous rearing of A. luctifer was carried out from 2005 to 2006, and its general biology is presented in this report. The preliminary host specificity test showed a promising result for using A. luctifer to control Rumex spp.  相似文献   
218.
Abstract The present paper is a part of the studies on the larvae of subfamily Galerucinae in Korea and Japan. Five species belonging to the Non-glanduliferous group in the subfamily Galerucinae were described and illustrated: Lochmaea capreae (Linnaeus), Atrachya menetriesi (Fladermann), Aulacophora indica (Gmelin), Exosoma flaviventre (Motschulsky), Fleutiauxia armata (Baly). A key and taxonomic remarks are also given.  相似文献   
219.
In this study, bacterial communities within the guts of several longicorn beetles were investigated by a culture-dependent method. A total of 142 bacterial strains were isolated from nine species of longicorn beetle, including adults and larvae. A comparison of their partial 16S rRNA gene sequences showed that most of the bacteria constituting the gut communities can typically be found in soil, plants and the intestines of animals, and approximately 10% were proposed as unreported. Phylogenetic analysis demonstrated that the bacterial species comprised 7 phyla, and approximately half were Gammaproteobacteria. Actinobacteria were the second most populous group (19%), followed by Firmicutes (13%) and Alphaproteobacteria (11%). Betaproteobacteria, Flavobacteria, and Acidobacteria were minor constituents. The taxonomic compositions of the isolates were variable according to the species of longicorn beetle. Particularly, an abundance of Actinobacteria existed in Moechotypa diphysis and Mesosa hirsute, which eat broadleaf trees; however, no Actinobacteria were isolated from Corymbia rubra and Monochamus alternatus, which are needle-leaf eaters. Considerable proportions of xylanase and pectinase producing bacteria in the guts of the longicorn beetles implied that the bacteria may play an important role in the digestion of woody diets. Actinobacteria and Gammaproteobacteria were the dominant xylanase producers in the guts of the beetles.  相似文献   
220.
Serratia proteamaculans HY-3 isolated from the digestive tract of a spider produces an extracellular protease named arazyme, with an estimated molecular mass of 51.5 kDa. The purified enzyme was characterized as having high activities at wide pH and temperature ranges. We further characterized biochemical features of the enzymatic reactions under various reaction conditions. The protease efficiently hydrolyzed a broad range of protein substrates including albumin, keratin, and collagen. The dependence of enzymatic activities on the presence of metal ions such as calcium and zinc indicated that the enzyme is a metalloprotease, together with the previous observation that the proteolytic activity of the enzyme was not inhibited by aspartate, cysteine, or serine protease inhibitors, but strongly inhibited by 1,10-phenanthroline and EDTA. The araA gene encoding the exoprotease was isolated as a 5.6 kb BamHl fragment after PCR amplification using degenerate primers and subsequent Southern hybridization. The nucleotide sequence revealed that the deduced amino acid sequences shared extensive similarity with those of the serralysin family of metalloproteases from other enteric bacteria. A gene (inh) encoding a putative protease inhibitor was also identified immediately adjacent to the araA structural gene.  相似文献   
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