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1.
2.
Univalent antibody (Fab fragments) against sperm-binding factor inhibits the fertilization of eggs species-specifically. The sperm-binding factor was partially purified from unfertilized eggs of the sea urchin Anthocidaris crassispina by monitoring its neutralizing effect on fertilization inhibiting Fab fragments. It formed two species-specific precipitin lines by the double-immunodiffusion test and gave three main bands of protein with apparent molecular weights of 80,000, 87,000 and 225,000, on sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Carbohydrate was detected in the first and third of these protein bands. 相似文献
3.
NATSUKO NARITA KENJI HASHIMOTO SHIN-ICHIRO TOMITAKA YOSHIO MINABE KOSUKE YAMAZAKI 《Addiction biology》1997,2(1):47-56
Abstract The non-competitive N-methyl-D-aspartate (NMDA) receptor antagonist such as an abused drug phencyclidine (PCP) causes the induction of heat shock protein HSP-70, a sensitive marker of neuronal injury, in the retrosplenial cortex of rat brain. The present study was undertaken to examine the role of a -amino-3- hydroxy-5-methyl-4-isoxazole propionate (AMPA) receptor in the expression of heat shock protein HSP-70 and hsp-70 mRNA in the retrosplenial cortex by PCP. Administration of PCP (50 mg/kg, i.p.) caused the induction of heat shock protein HSP-70 in the retrosplenial cortex of rat brain, whereas no HSP-70 immunoreactivity was detected in the vehicle-treated group. Pretreatment with a potent and selective AMPA receptor antagonist YM90K (1, 3 or 10 mg/kg, i.p; 15 min) inhibited in a dose dependent manner, the induction of heat shock protein HSP-70 by PCP (50 mg/kg). Furthermore, administration of PCP (50 mg/kg, i.p) caused marked expression of hsp-70 mRNA in the retrosplenial cortex of rat brain, whereas the expression of hsp-70 mRNA was NOT found in the vehicle-treated group. Pretreatment with YM90K (1, 3 or 10 mg/kg, i p; 15 min) also inhibited the expression of hsp-70 mRNA by PCP (50 mg/kg), in a dose-dependent manner. These results suggest that AMPA receptor may play a role in the expression of heat shock protein HSP-70 and heat shock gene hsp-70 mRNA in the retrosplenial cortex of rat brain by non-competitive NMDA receptor antagonists such as PCP. 相似文献
4.
Epstein-Barr Virus-associated Antigens in Non-producing Clones of Human Lymphoblastoid Cell Lines 总被引：4，自引：0，他引：4
NUCLEIC acid hybridization suggests that the Epstein-Barr virus (EBV) genome may be present in human lymphoblastoid cell lines that are free of detectable EBV1,2. We describe here a plentiful appearance of EBV-associated early antigens (EA) and the viral capsid antigen (VCA) in non-producing Raji and NC-37 cell lines when exposed to 5-bromodeoxyuridine (BUdR) or 5-iododeoxyuridine (IUdR). These antigens were synthesized in all the Raji and NC-37 clones exposed to BUdR or IUdR, strongly suggesting that a complete, but unexpressed, EBV genome exists in the cells of these non-producing lines. 相似文献
5.
The non-competitive NMDA receptor antagonists such as phencyclidine (PCP) cause neurotoxicity in the retrosplenial cortex of rat brain. However, the precise mechanism(s) underlying the neurotoxicity of NMDA receptor antagonists is currently unclear. Using an in situ hybridization technique, we studied the effects of PCP on expression of brain-derived neurotrophic factor (BDNF) mRNA in the rat brain. No expression of BDNA mRNA was observed in the retrosplenial cortex of rats treated with vehicle, although a high basal level of BDNF mRNA was detected in the hippocampus of control rats. Administration of PCP (12.5, 25 or 50 mg/kg, i.p., 6 hours) caused marked induction of BDNF mRNA in the retrosplenial cortex, in a dosedependent manner. These results suggest that the expression of BDNF mRNA may occur as a trophic response to the neurotoxicity of NMDA receptor antagonists such as PCP. 相似文献
6.
Morphological differences in body shape between females of different reproductive conditions (in terms of insemination and ovarian development) were examined in two species of the Neotropical polistine genus Parachartergus: P. smithii and P. fraternus. The present study shows, for the first time, that non‐size‐based morphological divergence between queens and workers occurs in Parachartergus, an epiponine genus once believed to have little or no morphological caste differences. In the P. smithii colony examined, queens were significantly larger than workers in five of the eight body parts measured (head width, eye width, genal width, mesosomal length, wing length, first metasomal tergum width, and width and length of the second tergum), but the mean values of wing length and first and second tergum widths were not significantly different between them. The queen : worker size ratios tended to be greater anteriorly and smaller posteriorly, although the size ratio was greatest in second tergum length. Analysis of covariance (ancova ) with mesosomal length as covariate showed that queens had proportionally wider heads and narrower first terga than did workers. In the P. fraternus colony, size differences between queens and workers were not significant, and there was little or no difference in shape, but queens had significantly proportionally wider first terga than did workers. 相似文献
7.
The queens of many social insects produce pheromones that influence the behaviour and physiology of colony members. Pheromones produced by queens have long been considered as the prime factor inhibiting the differentiation of new reproductive individuals. A volatile pheromone consisting of a blend of n‐butyl‐n‐butyrate and 2‐methyl‐1‐butanol comprises a queen pheromone that inhibits the differentiation of female neotenic reproductives (secondary queens) of a termite Reticulitermes speratus. 2‐Methyl‐1‐butanol is the first chiral molecule to be identified as a primer pheromone in social insects, which presents the intriguing question of whether enantiomeric composition plays a role in caste regulation. In the present study, we report that the (R)‐ and (S)‐enantiomers and the racemic mixture of 2‐methyl‐1‐butanol show significant inhibitory effects on the differentiation of new female neotenics in combination with n‐butyl‐n‐butyrate, whereas no significant difference in inhibitory activity is observed among them. These results suggests that termites recognize 2‐methyl‐1‐butanol as a queen signal but they do not distinguish between the stereostructures of the enantiomers. 相似文献
8.
Masayuki OKAUE Kazunori YAMAMOTO Yoshifumi TOUYAMA Takeshi KAMEYAMA Mamoru TERAYAMA Takashi SUGIYAMA Kyouzou MURAKAMI Fuminori ITO 《Entomological Science》2007,10(4):337-342
The distribution of the Argentine ant, Linepithema humile, was investigated in 65 cities or towns along the Seto Inland Sea, western Japan in 2003–2005. Our results include all available information of their distribution in Japan until 2005. Argentine ants have invaded Aichi Prefecture (Tahara‐shi), Hyogo Prefecture (Kobe‐shi), Hiroshima Prefecture (Hiroshima‐shi, Fuchu‐cho, Hatsukaichi‐shi, Ono‐cho and Otake‐shi), and Yamaguchi Prefecture (Iwakuni‐shi and Yanai‐shi). The most widespread distribution was found around Hatsukaichi‐shi including the westernmost part of Hiroshima‐shi and the easternmost of Ono‐cho. 相似文献
9.
Abstract.
- 1 Light traps have been widely used for surveying insect community structure, but some biases are known to occur under certain meteorological conditions.
- 2 In addition to weather factors, we raise the novel hypothesis that if the daily movement distance of focal insects is shorter than the effective range of the light trap, then the species richness and abundance of the daily captures will increase during the course of the night.
- 3 This study examined the daily attraction patterns of Lepidoptera and Coleoptera to light traps and the factors affecting the attraction of these communities. Light traps were run for three consecutive nights in each month from April to October 2001 in a cool‐temperate forest in Japan.
- 4 The species richness and abundance of Coleoptera increased during trap nights, whereas lepidopteran captures remained constant. Meteorological factors influenced the capture of both communities throughout the sampling season, but the daily increment in Coleoptera was not explained by the daily trends in weather conditions.
- 5 We argue that the daily augmentation of Coleoptera capture rate results from the daily movement distance of Coleoptera being generally shorter than the effective and perceivable range of the light traps. These results suggest that consideration of the typical daily movement of a focal taxon is required when conducting biological monitoring using light trap sampling.
10.
Abstract. 1. Ecological assemblages frequently show nestedness patterns of species distribution. Despite the common occurrence, the causality for nestedness patterns remains unclear. The effects of environmental and spatial factors on the patterns of insect species distributions were examined on 28 small islands in central Exuma, Bahamas. 2. Flying insects on each island were surveyed by Malaise traps, island area and vegetation height being used as environmental factors, and the degree of island isolation as a spatial factor. Body and relative wing length, and abundance of insect species were also considered as species traits which, together with environmental and spatial factors, determine insect distributions. 3. Island isolation was determined from distance to the mainland, greatest distance in a stepping‐stone pathway, distance to the nearest island, and the island area within 250, 500 and 1000 m of each island’s perimeter. 4. The pattern of island‐insect nestedness was examined for the overall insect assemblage and those of five dominant insect orders on the islands. The order of island ranking in the nested matrix was tested relative to area, isolation and vegetation height, the rank order of insect species then being examined relative to body and wing length, and abundance of species. 5. Significant nestedness was found in all assemblages. Significant contributions of environmental factors were found in Diptera and Hemiptera assemblages, whereas relatively large contributions of spatial factors were found in Lepidoptera and Hymenoptera assemblages. These results illustrated the need to include spatial factors in analyses on the assembly of insular insect assemblages. 相似文献