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1.
C-9-1, a monoclonal IgM antibody raised against human null cell acute lymphocytic leukemia cells reacted with restricted regions of embryonic and adult tissues of the mouse. The antigen positive sites in the embryos included embryonic ectoderm, visceral endoderm, trophoblastic cells invading the maternal decidua of 5∼7-day embryos, primordial germ cells of 10∼12-day embryos, epithelium of nasal chamber, the bronchus, Mullerian duct, epididymis and bladder of 12∼17-day embryos. In the adult mice, C-9-1 antigen was detected in renal tubules, a part of stomach, bladder, endometrium and epididymal sperm. Embryonal carcinoma cells, but not endodermal cells of teratocarcinoma expressed the antigen. Thus, C-9-1 antigen showed distribution similar to SSEA-1. However, C-9-1 antigen was not detected in preimplantation embryos, nor in oviduct, both of which are positive for SSEA-1.  相似文献   
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Previous studies have demonstrated that experimental type 1 diabetes induced by streptozotocin causes alterations in the biochemical and functional properties of several receptor systems in the rat bladder. However, the exact mechanism involved in the pathophysiology of voiding dysfunction in type 2 diabetic patients is unknown. Because the GK rat is a widely accepted genetically determined rodent model for human type 2 diabetes, we investigated diabetes-induced changes in the bladder smooth muscle of the GK rats at several time points. Male GK rats and age-matched Wistar rats, as controls, were maintained for 4, 8, 16, and 32 weeks. Contractile responses to KCl, carbachol, ATP, and electrical field stimulation (EFS) were measured by using the isolated muscle bath techniques. Acetylcholine (ACh) release induced by EFS from bladder muscle strips was measured by using high-performance liquid chromatography coupled with a microdialysis procedure. Maximum contractile responses to carbachol and ATP, the release of ACh, and tissue sorbitol levels were similar in bladders from GK and control rats until 8 weeks of age. At 16 weeks of age, however, the contractile responses to carbachol and ATP, and tissue sorbitol levels were increased, and the EFS-induced ACh release was decreased in GK rats compared with controls. Although the maximum contractile responses to EFS were unchanged until 16 weeks of age, they were decreased in 32-week-old GK rats, compared with controls. Our data indicate the presence of age-related alterations in the biochemical and functional properties of the bladder in type 2 diabetic GK rats.  相似文献   
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The grey‐crowned babbler (Pomatostomus temporalis) is a cooperative breeding bird species in which nonbreeding helpers of both sexes care for the young of breeding individuals. To measure the genetic relatedness between breeders and their offspring and helpers, we developed nine microsatellite markers. Most of the loci were highly polymorphic. These loci will be useful in understanding the evolution and maintenance of cooperative breeding and helping behaviour in this species.  相似文献   
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The ultrastructure of anionic sites in the middle layer of rat articular cartilages was studied by two methods, the quick-freezing and deep-etching method, and the quick-freezing and freeze-substitution method. The anionic sites were visualized with a cationic tracer, polyethyleneimine. They were also compared with those revealed in tissues subjected to conventional fixation, such as pre-embedding or post-embedding. With the deep-etching method, three-dimensional meshwork structures were observed more clearly in the extracellular matrix compared with those seen in conventional ultrathin sections. In combination with polyethyleneimine staining, in which no chemical contrast was needed for visualization of anionic sites, numerous stained particles were detected around filaments in the extracellular matrix, indicating that they were anionic sites consisting mainly of proteoglycans. With the pre-embedding method and polyethyleneimine staining, the shapes of aggregated stained particles varied with different preparation procedures, including chemical fixation and contrasting. The fine meshworks were also observed with the post-embedding method and polyethyleneimine staining. It is suggested that such images of anionic sites, as revealed by the deep-etching method and the post-embedding polyethyleneimine-staining method with low-temperature dehydration, are probably closer to native states than those revealed by the conventional pre-embedding polyethyleneimine-staining method. © 1998 Chapman & Hall  相似文献   
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KEISUKE UEDA 《Ibis》1989,131(2):257-262
In a population of Fan-tailed Warblers Cisticola juncidis near Osaka, Japan, the males were polygynous, building a succession of elaborate courtship nests within their territories, and advertising them to females. Nest desertion by females frequently occurred early in the breeding cycle. Deserted nests were generally left untouched, but 17 out of 88 territorial males cleaned and re-used 20 of 79 nests deserted by females for their next courtship. The frequency of nest re-use increased with season. Of the re-used nests six (300%) were re-occupied by secondary females. Newly built nests were preferred to the 'second-hand' nests, probably because new nests were likely to last longer. Breeding success did not differ between the two categories of nests. In males, nest re-use seems to save time and energy expenditure for additional mating.  相似文献   
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UEDA  K.; NONAKA  M. 《Annals of botany》1992,69(2):113-118
The division of chloroplasts in a green alga, Pediastrum duplex,was studied by electron microscopy. Cells were treated for observationwith the freeze-substitution method. Fibrils, or fibrous belts,which we had observed previously at the dividing constrictionsof chloroplasts in Trebouxia potteri were not visible in Pediastrum,even though the method of preparation was the same for bothsets of samples. Microtubules (MTs) and the septum seem notto participate directly in the division of the single chloroplastin Pediastrum cells. Many thin fibrils, 7–20 nm in diameter,attached to, or protruding from, the surface of the dividingconstriction were seen. These fibres were less densely distributedat the constrictions of non-dividing chloroplasts. It is suggestedthat these fibrils are involved in the divison of chloroplastsin Pediastrum duplex. Cell wall, chloroplast division, freeze-substitution, intermediate fibres, Pediastrum duplex, transmission electron microscopy  相似文献   
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Microsatellite markers were isolated from red‐flanked bushrobin, Tarsiger cyanurus, for parentage analysis. From an enriched genomic library using the fast isolation by AFLP of sequences containing repeats (FIASCO) method, six polymorphic loci were obtained. Seven to 21 alleles were identified in an analysis of 19 red‐flanked bushrobin, with observed heterozygosity ranging from 0.842 to 1.00. All loci showed Hardy–Weinberg equilibrium and linkage equilibrium. Total exclusion probability using six loci was 0.998 for neither parent known, and 0.999 for one parent known. We also tested the utility of these loci on four species of Turdidae. Although one of the loci failed to amplify in any species, the other primers successfully amplified in at least two of the species we tested.  相似文献   
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The DBA/2J strain is a model for early-onset, progressive hearing loss in humans, as confirmed in the present study. DBA/2J mice showed progression of hearing loss to low-frequency sounds from ultrasonic-frequency sounds and profound hearing loss at all frequencies before 7 months of age. It is known that the early-onset hearing loss of DBA/2J mice is caused by affects in the ahl (Cdh23ahl) and ahl8 (Fscn2ahl8) alleles of the cadherin 23 and fascin 2 genes, respectively. Although the strong contributions of the Fscn2ahl8 allele were detected in hearing loss at 8- and 16-kHz stimuli with LOD scores of 5.02 at 8 kHz and 8.84 at 16 kHz, hearing loss effects were also demonstrated for three new quantitative trait loci (QTLs) for the intervals of 50.3–54.5, 64.6–119.9, and 119.9–137.0 Mb, respectively, on chromosome 5, with significant LOD scores of 2.80–3.91 for specific high-frequency hearing loss at 16 kHz by quantitative trait loci linkage mapping using a (DBA/2J × C57BL/6J) F1 × DBA/2J backcross mice. Moreover, we showed that the contribution of Fscn2ahl8 to early-onset hearing loss with 32-kHz stimuli is extremely low and raised the possibility of effects from the Cdh23ahl allele and another dominant quantitative trait locus (loci) for hearing loss at this ultrasonic frequency. Therefore, our results suggested that frequency-specific QTLs control early-onset hearing loss in DBA/2J mice.  相似文献   
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