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991.
Objective: The purpose of the present study is to clarify the frequency of provision of effective professional oral care by dental health workers in order to improve the oral hygiene state of elderly persons requiring long‐term care. Methods: In 105 patients requiring long‐term nursing care, 55 subjects with positive oral Candida albicans were divided into five groups according to the frequency of oral care intervention at intervals of 1, 2, 3, 4 and 6 weeks. The effects of professional oral care on the improvement of the oral hygiene state were investigated taking the frequency and duration of care into consideration. Results: The results showed that oral hygienic condition could be improved by performing professional oral care at intervals of 1 week for 12 consecutive weeks, and the improved condition could be maintained when professional oral care was continued at intervals of 1 week thereafter. Conclusion: It is necessary to continue professional oral care at intervals of 1 week for 12 consecutive weeks and at intervals of 2 weeks for more than 20 weeks. The oral hygiene state could be improved by professional intervention at intervals of three or four weeks in long‐term oral care, but this was limited to subjects whose Functional Independence Measure (FIM) scores were higher than 3.  相似文献   
992.
In the present study, we conducted an extensive analysis to identify novel genes with developmental function among Ciona intestinalis genes discovered by cDNA projects. Translation of a total of 200 genes expressed during embryogenesis was suppressed by using specific morpholino antisense oligonucleotides. Suppression of the translation of any of 40 genes (one-fifth of the genes tested) was thereby shown to cause specific embryonic defects. Most of these genes have counterpart(s) in mouse and human, suggesting that the present approach will be useful for identifying candidate genes essential for the development of vertebrates. Suppression of translation of 14 of these 40 genes resulted in the 'disorganized body plan' phenotype characterized by gross morphological abnormalities caused by early defects in embryogenesis. These genes encode zinc-finger, transmembrane or Pbx homeodomain proteins. The morphological features of larvae of this phenotypic class varied according to the gene suppressed, suggesting that a distinct developmental event such as tissue specification or cell cycle progression was affected in each type of larva. Suppression of the remaining 26 genes resulted in the 'abnormal tail' phenotype. Some of these genes encode proteins with known functional structures such as Zn-finger and HLH motifs. Twelve genes among them are especially interesting, because their suppression produced defects in the nervous system, as demonstrated by the loss of the sensory pigment cells or palps of the adhesive organ in the knockdown larvae. These results suggest that screening for developmental genes by the reverse genetic approach in Ciona intestinalis embryos is effective for identifying novel genes with developmental functions required for the development of chordates.  相似文献   
993.
Although nine diacylglycerol kinase (DGK) isozymes have been identified, our knowledge of their individual functions is still limited. Here we report that the levels of DGKgamma mRNA/protein in human leukemia HL-60 and U937 cells were rapidly and markedly decreased upon cellular differentiation into macrophages. In contrast, the enzyme expression remained almost unchanged in granulocytic differentiation pathway. Interestingly, the overexpression of wild-type or constitutively active DGKgamma, but not its kinase-dead mutant, markedly inhibited phorbol ester-induced cell attachment and nonspecific esterase activity, which are hallmarks of macrophage differentiation. We noted in this case that no effects were observed for the corresponding constructs of a closely related isozyme, DGKalpha. Prior to the cell attachment, phorbol ester induced translocation of DGKgamma from the cytoplasm to the cell periphery, resulting in its co-localization with F-actin together with protein kinase Cdelta. The results suggest that DGKgamma negatively regulates macrophage differentiation through its catalytic action operating on the cytoskeleton.  相似文献   
994.
We studied intergroup encounters among moor macaques at the Karaenta Nature Reserve, South Sulawesi, Indonesia. Group B has been observed on the basis of individual identification since 1988. We analyzed 85 encounters between members of Group B and members of neighboring groups from September 1990 to November 1998. The average frequency of intergroup encounters was 0.035/hour. Neither the presence of females in estrus nor rainfall had an effect on encounter frequency. Behaviors of moor macaques during intergroup encounters differed from those of Japanese macaques. In moor macaques, no intergroup interactions with body contact were observed during encounters, and females never directed aggression toward members of different groups. The present study did not confirm the prediction of the model ofvan Schaik (1989). Extension of the existing models is required to explain the difference in female dominance styles among macaques by socioecological factors.  相似文献   
995.
Monolayer cell cultures and cartilage tissue fragments have been used to examine the effects of hydrostatic fluid pressure (HFP) on the anabolic and catabolic functions of chondrocytes. In this study, bovine articular chondrocytes (bACs) were grown in porous three-dimensional (3-D) collagen sponges, to which constant or cyclic (0.015 Hz) HFP was applied at 2.8 MPa for up to 15 days. The effects of HFP were evaluated histologically, immunohistochemically, and by quantitative biochemical measures. Metachromatic matrix accumulated around the cells within the collagen sponges during the culture period. There was intense intracellular, pericellular, and extracellular immunoreactivity for collagen type II throughout the sponges in all groups. The incorporation of [(35)S]-sulfate into glycosaminoglycans (GAGs) was 1.3-fold greater with constant HFP and 1.4-fold greater with cyclic HFP than in the control at day 5 (P < 0.05). At day 15, the accumulation of sulfated-GAG was 3.1-fold greater with constant HFP and 2.7-fold with cyclic HFP than the control (0.01). Quantitative immunochemical analysis of the matrix showed significantly greater accumulation of chondroitin 4-sulfate proteoglycan (C 4-S PG), keratan sulfate proteoglycan (KS PG), and chondroitin proteoglycan (chondroitin PG) than the control (P < 0.01). With this novel HFP culture system, 2.8 MPa HFP stimulated synthesis of cartilage-specific matrix components in chondrocytes cultured in porous 3-D collagen sponges.  相似文献   
996.
We established three transgenic medaka fish lines overexpressing the medaka estrogen receptor under the constitutive medaka beta-actin promoter. The transgenic embryos became hypersensitive to estrogens (17 beta-estradiol and 17alpha-ethinylestradiol), and failed to develop yolk veins while blood clots formed in the blood island within 3 days after exposure to the estrogens. The embryos developed normally if exposed to estrogen after an early neurula stage, suggesting that the sensitive stage is before neurulation. The developmental defects were recovered by incubation with an anti-estrogen, tamoxifen. These results indicate that activation of estrogen receptor caused the estrogen-induced developmental defects. Our results show that the transgenic embryos can be used to assay the blood clotting activity of estrogenic compounds in vivo.  相似文献   
997.
We analyzed lateral propagation of epidermal growth factor (EGF) signaling in single live COS cells following local stimulation, achieved by the use of laminar flows containing rhodamine-labeled EGF. The spatiotemporal pattern of EGF signaling was visualized by fluorescent indicators for Ras activation and tyrosine phosphorylation. Contrary to the findings in previous reports, both signals were localized to the stimulated regions in control COS cells expressing EGF receptor at the basal level. However, the signals spread over the entire cell when EGF receptors were overexpressed or when receptor/ligand endocytosis was blocked. We thus present evidence that ligand-independent propagation of EGF signaling occurs only when the receptor density on the plasma membrane is high, such as in carcinoma cells.  相似文献   
998.
The mixing performance as well as the adsorption performance in expanded bed chromatography (EBC) was investigated by using various types of adsorption media (average particle size = 100–700 m, density = 1100–1700 kg/m3, base matrix = hydroxyapatite, styrene-divinylbenzene, cross-linked agarose). The scale down study with 0.8 cm diameter columns was also attempted. Pulse response curves were measured with vitamin B12 as a tracer [Residence time distribution RTD experiments], and the HETP (height equivalent to a theoretical plate or plate height) values were calculated from the peak variance and the peak retention time. The HETP values for different types of packing media tested showed very similar values (0.5–1.0 cm), which did not depend on the flow-rate or the column diameter (0.8–2.6 cm). Dynamic binding capacity (DBC) values of lactic acid on a Dowex anion-exchange resin were determined from breakthrough curve (BTC) measurements for both EBC and fixed bed chromatography (FBC). The DBC values for EBC were similar to those for FBC. When the liquid feed contained insoluble particles (yeast cells) the degree of mixing increased. However, the contribution of the mixing to the total spreading of BTCs for EBC was usually small so that this increase in the mixing did not affect the adsorption performance or the DBC values significantly.  相似文献   
999.
We experimentally tested the indirect and direct effects of Amblyseius womersleyi on Tetranychus kanzawai. The presence of A. womersleyi indirectly reduced egg production of T. kanzawai by 25.9%, although this effect had less impact than direct egg predation. The mechanism of this indirect effect could be explained by behavioral changes in T. kanzawai females; in the presence of A. womersleyi, T. kanzawai females allocated more time to seeking refuge on webs at the expense of feeding on leaves.  相似文献   
1000.
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