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891.
A series of work by the first author have demonstrated that many macaque species show a visual preference for the pictures of their own species when the monkeys actively press a lever to see the pictures. We expanded this study to Sulawesi macaques kept as a pet by local people with slight modification. All seven species of Sulawesi macaques were passively exposed to a variety of colored slides of Sulawesi macaques. The experimenter recorded the duration of visual fixation onto the pictures. Male monkeys of all the seven species clearly watched the pictures of their own species for longer duration than those of the other species. Such visual preference suggested that the seven Sulawesi macaques discriminate each other species and, thus, they may not be integrated into fewer number of species. This visual preference may work to prevent overall intergradation of the Sulawesi macaques who sometimes have hybrid zones only in limited areas. This preference was in general weaker in female monkeys. In one species,Macaca ochreata, females actively avoided to see the pictures of conspecifics. These results may be related to how female monkeys interact with other individuals.  相似文献   
892.
Human serum albumin is a mixture of mercapt- (HMA, reduced form) and nonmercaptalbumin (HNA, oxidized form). We studied the mercapt↔nonmercapt conversion of human serum albumin, which reflects the redox state of the extracellular fluids, in cardiac and other common surgical patients using high-performance liquid chromatography. Mean values of [(HMA)/(HMA + HNA)] ± standard deviation [fHMA ± σ], for patients who received common surgery (group 1) and cardiac surgery (group 2) at the start of anesthesia were0.636±0.50(n=83) and 0.615±0.062(n=14), respectively. fHMA values were markedly lower than those for healthy male adults of 0.750±0.028(n=28). fHMA values increased at 24 h after the start of anesthesia and decreased on the 4th postoperative day in most of the patients. These postoperative changes were prominent in surgical cardiac patients. Although fHMA values after the 7th postoperative day recovered to those at the start of anesthesia in almost all of common surgical patients, those in cardiac surgical patients, never recovered even on the 21st postoperative day.  相似文献   
893.
Abstract. In the cool-temperate Bibi Mire, Hokkaido, Japan, valley fens and flood-plain fens have quite different vegetation. The main variables controlling the vegetation were all hydrological: mean water level, water level fluctuation and surface water flow. Chemical factors such as electrical conductivity, dissolved oxygen and related peat decomposition were less important. The pH was about neutral and has little effect. The flood-plain fen developed under fluctuating water table conditions. The dominant species are Calamagrostis langsdotffii and Carex pseudocuraica. When temporal inundation occurs in the rainy or typhoon seasons, the submergence stimulates bud germination of the stoloniferous C. pseudocuraica, which can rapidly elongate its stolons upward. Some large floating peat mats occurred in the flood-plain fen zone. On these mats some Alnus japonica saplings establish and patches of alder forest can arise. Here the water level was higher than in the peripheral alder forest zone. The valley fen is dominated by Carex lasiocarpa var. occultans and/or C. limosa. It is formed under stable water table conditions in the inundated parts of the mire -where the non-inundated wet areas are dominated by alder trees. In the area where the surface water is flowing, these two fen sedges grow in deeper water since the high oxygen content is considered to compensate the flooding stress.  相似文献   
894.
Patapius spinosus, a remarkable leptopodid bug whose body is covered with spines, was collected for the first time in Japan. This species was found in the supralittoral zone of a sandy beach in Osaka Prefecture, central Japan, in autumn 2002 and in spring 2004. Patapius spinosus is known to be distributed in the Mediterranean and North African regions, and has been introduced into North America and Chile. Its occurrence in Japan could signify either an eastern limit of its native distribution or an exotic origin.  相似文献   
895.
We updated a database of microsatellite marker polymorphisms found in inbred strains of the mouse, most of which were derived from the wild stocks of four Mus musculus subspecies, M. m. domesticus, M. m. musculus, M. m.castaneus and M. m. molossinus. The major aim of constructing this database was to establish the genetic status of these inbred strains as resources for linkage analysis and positional cloning. The inbred strains incorporated in our database are A/J, C57BL/6J, CBA/J, DBA/2J, SM/J, SWR/J, 129Sv/J, MSM/Ms, JF1/Ms, CAST/Ei, NC/Nga, BLG2/Ms, NJL/Ms, PGN2/Ms, SK/CamEi and SWN/Ms, which have not or have only been poorly incorporated in the Whitehead Institute/MIT (WI/MIT) microsatellite database. The number of polymorphic microsatellite loci incorporated in our database is over 1,000 in all strains, and the URL site for our database is located at http:// www.shigen.nig.ac.jp /mouse/mmdbj/mouse.html.  相似文献   
896.
897.
The time-dependent effects of daily dosing of IGF-I (1.21 mg/g) on the linear growth of the femur were investigated in mice. The femoral length and volume and the number of osteoclasts were significantly greater after IGF-I injection as compared to the non-injected control, suggesting that the IGF-I imbalance might cause a quick turnover cycle of the bone resulting in the altered femoral modeling.  相似文献   
898.
899.
Transient electric birefringence of poly(L -α,γ-diaminobutyric acid hydrochloride) in methanol/water mixtures has been measured over a wide range of field strengths and solvent compositions and at different polymer concentrations and temperatures. The molar ellipticity at 222 nm and the specific Kerr constant underwent an abrupt change between 75 and 80 vol % methanol at 25°C, accompanied by a solvent-induced helix–coil transition. Anomalous birefringence transients were observed between 78 and 80 vol% methanol above threshold field strengths. The double logarithmic plots of the steady-state specific birefringence versus the square of field strength for different solvent compositions and polymer concentrations could be superimposed by shifting them horizontally along the abscissa and vertically along the ordinate except for the range where anomalous transients were observed. The threshold field strength could be estimated from the point at which a downward deviation occurred. It increased with increasing polymer concentration and with increasing methanol content on the verge of the transition region. The results were interpreted as indicating that a conformational change from the charged helix to the charged coil is induced by high fields in this system, as in the case of poly(L -lysine hydrobromide) in methanol/water mixtures.  相似文献   
900.
BACKGROUND: A cell-based assay system (Transfluor) has been developed for measurement of G-protein coupled receptor (GPCR) activity by using cells transfected to express a fusion protein of arrestin plus green fluorescent protein (GFP) and the target GPCR. Upon agonist stimulation, the arrestin-GFP translocates to and binds the activated GPCR at the plasma membrane. The receptor/arrestin-GFP complexes then localize in clathrin-coated pits and/or intracellular vesicles. This redistribution of arrestin-GFP into condensed fluorescent spots is useful for visually monitoring the active status of GPCRs and its quantitation is possible with certain types of digital image analysis systems. METHODS: We designed two lines of image processing algorithms to carry out quantitative measurement of the arrestin-GFP movement on an inverted version of laser scanning cytometry (iCyte) as an imaging platform. We used a cell line expressing arrestin-GFP and the wild-type beta2-adrenergic receptor or a modified version of this receptor with enhanced affinity for arrestin. Each cell line was challenged with various concentrations of agonist. RESULTS: A dose-dependent signal was measured and half-maximal effective concentration values were obtained that agreed well with results determined by other methods previously reported. CONCLUSIONS: The results indicate that the combination of Transfluor, iCyte, and our algorithms is suitable for robust and pharmacologically relevant GPCR ligand exploration.  相似文献   
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