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31.
Clinical inspections were carried out in order to obtain sufficient information concerning the physiological characteristics and states of natural infection by various pathogenic agents in the population of crab-eating macaques (Macaca fascicularis) on Mauritius. The hematological and plasma biochemical values were within the normal ranges, showing no morbid signs. The intestinal parasitic appearance was so simplified that onlyStrongyloides andTrichuris were noted as helminthic findings. All of the monkeys examined were free from enteropathogenic organisms such asShigella andSalmonella, and were negative for measles, herpes simplex type 1, simian immunodeficiency virus/MAC, and SV5 antibodies. These data suggest that the macaques in Mauritius are considerably spared from natural infections by various pathogenic agents. This study was carried out under the humane conditions prescribed in “The Guidelines for the Study of Wild Primates and Use of Wild-born Primates” by the Primate Research Institute, Kyoto University, Japan.  相似文献   
32.
Parasite-induced behavioral changes in their hosts favor to complete the lifecycle of parasites. Schistosome infection is also known to cause physiological changes in infected freshwater snail intermediate hosts. Here, we report, a novel phenomenon in which Schistosoma mansoni, a highly debilitating worm affecting millions of people worldwide, alters the phototropic behavior of Biomphalaria glabrata, the vector snail. S. mansoni-infection enhanced positive phototropism of vector snails and infected snails spent significantly more time in light. Possibly, these behavioral changes help the parasite to be released efficiently from the infected intermediate hosts, and to infect mammalian hosts.  相似文献   
33.
A physical map of the unicellular cyanobacterium Synechococcus sp. strain PCC6301 genome has been constructed with restriction endonucleases PmeI, SwaI, and an intron-encoded endonuclease I-CeuI. The estimated size of the genome is 2.7 Mb. On the genome 49 genes or operons have been mapped. Two rRNA operons are separated by 600 kb and transcribed oppositely.  相似文献   
34.
[NBun4]2[W(C3Se5)3] (C3Se52− = 1,3-diselenole-2-selone-4,5- diselenolate(2−)) was prepared by the reaction of Na2[C3Se5] with WCl6 in ethanol, followed by addition of [NBun4]Br. The cyclic voltammogram in dichloromethane exhibits two oxidation peaks at −0.04 and +0.03 V (versus SCE). The complex reacted with [Fe(C5Me5)2][BF4], iodine or [TTF]3[BF4]2 (TTF·+ = the tetrathiafulvalenium radical cation) in acetonitrile to afford the oxidized complexes [Fe(C5Me5)2]0.5[W(C3Se5)3], [NBun4]0.1[W(C3Se5)3] and [TTF]0.5[W(C3Se5)3], respectively. Current-controlled electrochemical oxidation of the complex in acetonitrile gave [NBun4]0.6[W(C3Se5)3]. The oxidized complexes exhibit electrical conductivities of 4.7×10 −5−1.5×10−3 S cm−1 at room temperature measured for compacted pellets. Electronic absorption, IR and ESR spectra of these complexes are discussed.  相似文献   
35.
A part of the tRNALeu (UAA) gene containing a 240-nucleotidegroup I intron was amplified by PCR from cyanobacterium SynechococcusPCC 6301 genomic DNA. The pre-tRNA synthesized from the clonedPCR product was efficiently self-spliced in vitro under physiologicalconditions. The gene encoding the tRNALeu (UAA), trnL-UAA, wasisolated from a Synechococcus PCC 6301 genomic library and thenucleotide sequence of a 2,167-bp portion was determined. ThetrnL-UAA consists of a 34-bp 5' exon, a 240-bp group I intronand a 50-bp 3' exon. In addition, three open reading frames(ORF1, ORF2 and ORF3) were found in the 5' and 3' flanking regionsof trnL-UAA. The predicted protein sequence of ORF3, which islocated 74-bp upstream from trnL-UAA on the opposite strand,shows 66.2% amino acid identity to that of the SynechocystisPCC 6803 gene encoding subunit L of NADH dehydrogenase (ndhL).  相似文献   
36.
Phytosulfokine-alpha (PSK-alpha), a sulfated growth factor (H-Tyr(SO3H)-Ile-Tyr(SO3H)-Thr-Gln-OH) universally found in both monocotyledons and dicotyledons, strongly promotes proliferation of plant cells in culture. In our studies on structure/activity relationship in PSK-alpha the synthesis of a series of analogues was performed: [H-D-Tyr(SO3H)1]- (9), [H-Phe(4-SO3H)1]- (10), [H-D-Phe(4-SO3H)1]- (11), [H-Phg(4-SO3H)1]- (12), [H-D-Phg(4-SO3H)1]- (13), H-Phe(4-NHSO2CH3)1]- (14), [H-D-Phe(4-NHSO2CH3)1]- (15), [H-Phe(4-NO2)1]- (16), [H-D-Phe(4-NO2)1]- (17), [H-Phg(4-NO2)1]- (18), [H-D-Phg(4-NO2)1]- (19), [H-Hph(4-NO2)1]- (20), [H-Phg(4-OSO3H)1]- (21), [Phe(4-NO2)3]- (22), [Phg(4-NO2)3]- (23), [Hph(4-NO2)3]- (24), [H-Phe(4-SO3H)1, Phe(4-SO3H)3]- (25) [H-Phe(4-NO2)1, Phe(4-NO2)3]- (26), [H-Phg(4-NO2)1, Phg(4-NO2)3]- (27), [H-Hph(4-NO2)1, Hph(4-NO2)3]- (28) and [Val3]- PSK-alpha (29). For modification of the PSK-alpha peptide chain the novel amino acids and their derivatives were synthesized, such as: H-L-Phg(4-SO3H)-OH (1), H-D-Phg(4-SO3H)-OH (2), Fmoc-Phg(4-SO3H)-OH (3), Fmoc-D-Phg(4-SO3H)-OH (4), Boc-Phg(4-NHSO2CH3)-OH (5), Boc-D-Phg(4-NHSO2CH3)-OH (6) Boc-Phe(4-NHSO2CH3)-OH (7), and Boc-D-Phe(4-NHSO2CH3)-OH (8). Peptides were synthesized by a solid phase method according to the Fmoc procedure on a Wang-resin. Free peptides were released from the resin by 95% TFA in the presence of EDT. All peptides were tested by competitive binding assay to the carrot membrane using 3H-labelled PSK according to the Matsubayashi et al. test.  相似文献   
37.
In interspecific crosses, a mismatch in internal physiological conditions between two species can reduce sperm viability in the interval from insemination to fertilization, leading to gametic isolation. Two closely related Japanese phytophagous ladybird beetles, Henosepilachna vigintioctomaculata and H. pustulosa, show several isolating barriers, including reduction in the number of heterospecific sperm in the female reproductive tract and low egg‐hatching rates in interspecific matings. However, the mechanisms of these two potential isolating barriers and the association between them are unknown. Here we investigated temporal changes in the number of sperm stored in the female reproductive tract and egg‐hatching rates in inter‐ and intraspecific crosses between these species. Although the number of sperm decreased after both inter‐ and intraspecific crosses, the reduction was more drastic in inter‐ than in intraspecific crosses for females of both species. Most of the sperm reduction occurred early on, during sperm transfer from the bursa copulatrix to the paired ampullae of the common oviduct (the sperm storage organs). These two species also demonstrated stably low egg‐hatching rates in interspecific crosses. Since the degree and timing of the sperm reduction did not correlate with egg‐hatching rates, the reduction in heterospecific sperm in interspecific crosses may not directly cause the low hatching rates. These two isolating barriers could be different expressions of the physiological mismatch and/or genetic incompatibility between gametes of these species.  相似文献   
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