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171.
Serum Bone Gla Protein (BGP) levels were measured by both immunoradiometric assay (IRMA) and radioimmunoassay (RIA) to investigate the effect of intermittent 1,25(OH)2D3 administration to dialysis patients who could not tolerate an increase in an active vitamin D3 dose and/or calcium to control secondary hyperparathyroidism due to hypercalcemia. The administration of active vitamin D3 gradually increased the serum BGP to more than 3 times the original level by the 8th week. At the 12th week after starting the active vitamin D3 therapy, mean BGP was about twice the original level, which was about half the maximum level at the 8th week. The BGP (IRMA)/BGP (RIA) ratio was increased significantly at 4th and 8th weeks compared to the original level. During this period, serum calcium, phosphorous, or intact molecule PTH (I-PTH) levels showed insignificant changes, with a slight reduction in the mid molecule PTH (m-PTH) level, and a significant reduction in ALP. Serum BUN and creatinine levels were not changed significantly. These data suggest that BGP was increased through direct stimulation of osteoblasts by the active vitamin D3, and the increase was not due to deterioration of secondary hyperparathyroidism. The reduction of the increase in the BGP level at the 12th week with insignificant biochemical changes suggest that activation of osteoblasts by vitamin D3 may be transient. In conclusion, intermittent active vitamin D3 increases serum BGP, without deterioration of major biochemical changes even in patients with moderate to severe secondary hyperparathyroidism, although the increase may be transient. These facts suggest that the serum BGP of hemodialysis patients is controlled at least in part by active vitamin D3.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
172.
173.
Epithelial cells of chicken proventriculus (glandular stomach) differentiate into two types; luminal and glandular epithelial cells. The molecules regulating the differentiation of proventricular epithelial cells are not well understood. As the first step in screening the molecular determinants involved in the cell differentiation process, we tried to establish an in vitro culture system for isolated proventricular epithelial cells. Various basal media, growth factors and sera were tested. The medium that supports well the proliferation of epithelial cells was composed of Ham's F12 as the basal medium with epidermal growth factor (10 μg/mL), insulin (10 μg/mL), cholera toxin (1 μg/mL) and bovine pituitary extract (100 μg/mL). Fetal calf serum stimulated cell proliferation 1.7-fold, while horse serum was rather toxic. Proventricular epithelial cells proliferated for 3 days, but began to die out within 1 week of culture. Cultured epithelial cells never expressed embryonic chicken pepsinogen (ECPg), a marker gene of glandular epithelial cells, or maintained ECPg expression. The capacity for ECPg expression in cultured epithelial cells was analyzed by recombination with the proventricular mesenchyme and ECPg was detected in epithelial cells cultured up to 3 days. We concluded therefore, that epithelial cells keep the capacity for ECPg expression for 3 days of cultivation and proventricular mesenchymal cells are required for the actual expression of the ECPg gene.  相似文献   
174.
A new chemotype (C type) ofPerilla frutescens (Labiatae) that accumulatestrans-citral as a main component of the essential oil in the leaf was crossed with five other chemotypes containing perillaldehyde (PA), elsholtziaketone (EK), perillaketone (PK), perillene (PL), and phenylpropanoid (PP) as their respective major components for comparison of genetic differences. The analyses of F1 and F2 progenies showed thattrans-citral is accumulated when its metabolism is blocked in the simultaneous absence of a dominant geneN, which is involved in the conversion oftrans-citral into naginataketone viacis-citral, and two polymeric genesFr 1 andFr 2 , which are involved in the conversion oftrans-citral into perillene. On the basis of new data obtained from various intercrosses involving the C type as one of the parents, the genotypes of different chemotypes as well as the sites of action of several genes controlling reaction steps in the biosynthesis of monoterpenes inPerilla have been revised.  相似文献   
175.
176.
A murine monoclonal antibody recognizing (1→6)-β-d -glucopyranosyl laminaritriose (G4) was prepared by immunizing BALB/c mice with G4-bovine serum albumin conjugate and fusing the splenocytes with mouse myeloma cells. The monoclonal antibody (IgM) provoked by the cloned cells showed low reactivity with schizophyllan, an antitumor polysaccharide, but notable reactivity with some low-molecular-weight schizophyllans. This antibody was useful for determination of the epitope of several polysaccharides. The extent of reactivity of this monoclonal antibody was related only to the molecular weight of schizophyllan.  相似文献   
177.
We isolated full-length cDNA clones from size-fractionated cDNAlibraries of human immature myeloid cell line KG-1, and thecoding sequences of 40 genes were newly predicted. A computersearch of the GenBank/EMBL databases indicated that the sequencesof 14 genes were unrelated to any reported genes, while theremaining 26 genes carried some sequences with similaritiesto known genes. Significant transmembrane domains were identifiedin 17 genes, and protein motifs that matched those in the PROSITEmotif database were identified in 11 genes. Northern hybridizationanalysis with 18 different cells and tissues demonstrated that10 genes were apparently expressed in a cell-specific or tissue-specificmanner. Among the genes predicted, half were isolated from themedium-sized cDNA library and the other half from the small-sizedcDNA library, and their average sizes were 4 kb and 1.4 kb,respectively. As judged by Northern hybridization profiles,small-sized cDNAs appeared to be expressed more ubiquitouslyand abundantly in various tissues, compared with that of medium-sizedcDNAs.  相似文献   
178.
A fungus was found to be stored in the mycangia of a horntail,Tremex longicollis, as hyphal fragments. All fungal isolates from the mycangia of 31 adult females of the horntail produced the same colonies on PDA. Basidiocarps ofCerrena unicolor occurred near the emergence hole of the horntail on a dead hackberry tree (Celtis sinensis). The cultures of this fungus were similar to those from the mycangia of the horntail in cultural characteristics. Mating between single-basidiospore mycelia ofC. unicolor and single-arthrospore mycelia from the mycangia of the horntail showed that they were compatible. These results revealed that the fungus isolated from the mycangia ofT. longicollis wasC. unicolor.  相似文献   
179.
A fine physical map of Arabidopsis thaliana chromosome 5 wasconstructed by ordering the clones from YAC, P1, TAC and BAClibraries of the genome using the sequences of a variety ofgenetic and EST markers and terminal sequences of clones. Themarkers used were 88 genetic markers, 13 EST markers, 87 YACend probes, 100 YAC subclone end probes, and 390 end probesof P1, TAC and BAC clones. The entire genome of chromosome 5,except for the centromeric and telomeric regions, was coveredby two large contigs 11.6 Mb and 14.2 Mb long separated by thecentromeric region. The minimum tiling path of the chromosomewas constituted by a total of 430 P1, TAC and BAC clones. Themap information is available at the Web site http://www.kazusa.or.jp/arabi/.  相似文献   
180.
Periodic food availability can act as a potent zeitgeber capable of synchronizing many biological rhythms in fishes, including locomotor activity rhythms. In the present paper we investigated entrainment of locomotor rhythms to scheduled feeding under different light and feeding regimes. In experiment 1, fish were exposed to a 12:12?h light/dark cycle and fed one single daily meal in the middle of the light phase. In experiment 2, we tested the effect of random versus scheduled feeding on the daily distribution of activity. During random feeding, meals were randomly scheduled with intervals ranging from 12 to 36?h, while scheduled feeding consisted of one single daily meal set in the middle of the light or dark phase. Finally, in experiment 3, we studied the synchronization of activity rhythms to feeding under constant darkness (DD) and after shifting the feeding cycle by either advancing or delaying the feeding cycle by 9?h. The results revealed that goldfish synchronized to feeding, overcame light entrainment and significantly changed their daily distribution of activity according to their feeding schedule. In addition, the daily activity pattern modulated by feeding differed between layers: a peak of activity being noticeable directly after feeding at the bottom, while an anticipatory behaviour was obvious at the surface of the tank. Under DD and no food, free-running rhythms averaging 25.5?± 1.9?h (mean?±?SD) were detected. In conclusion, some properties of feeding entrainment (e.g. anticipation of the feeding time, free-running rhythms following termination of periodic feeding, and the stability of ø after shifting the feeding cycle) suggested that goldfish have (a) separate but tightly coupled light- and food-entrainable oscillators, or (b) a single oscillator that is entrainable by both light and food (one synchronizer being eventually stronger than the other).  相似文献   
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