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181.
182.
The ruthenium(III) complex [(Cp*)RuCl2]2 (Cp*=permethylcyclopentadienyl) catalyzes polymerization of propiolic acid to give a mixture of poly(propiolic acid), [---CH=C(COOH)---]n (1), and cyclic trimers, 1,2,4- and 1,3,5- benzenetricarboxylic acids. GPC analysis shows MN and MW values of the polymer of 4.0 × 103 and 4.3 × 103, respectively. Reaction of propiolic acid in the presence of the Ru(II) complex, (Cp*)RuCI(L) (L=1,5-cyclooctadiene and norbornadiene), gives the cyclic trimers rather than 1. [(Cp*)RuCl2]2 catalyzes polymerization of acetylenedicarboxylic acid and of propargyl alcohol to give the corresponding poly(acetylene) derivatives, [---C(COOH)=C(COOH)---]n (2) and [---CH=C(CH2OH)---]n (3), respectively. Polymerization of ethyl propiolate, 2-butyn-1,4-diol, phenylacetylene and (trimethylsilyl)acetylene using [(Cp*)RuCl2]2 gives the corresponding polymers [---CH=C(COOEt)---]n (4), [---C(CH2OH)=C(CH2OH)---]n (5), [---CH=CPh---]n (6) and [---CH=C(SiMe3)---]n (7) in low yields. 相似文献
183.
184.
We studied the effect of deuterium oxide (D2O) on contraction characteristics and ATPase activity of single glycerinated muscle fibers of rabbit psoas. D2O increased the maximum isometric force P0 by about 20%, while the force versus stiffness relation did not change appreciably. The maximum shortening velocity under zero load Vmax did not change appreciably in D2O, so that the force-velocity (P-V) curve was scaled depending on the value of P0. The Mg-ATPase activity of the fibers during generation of steady isometric force P0 was reduced by about 50% in D2O. Based on the Huxley contraction model, these results can be accounted for in terms of D2O-induced changes in the rate constants f1 and g1 for making and breaking actin-myosin linkages in the isometric condition, in such a way that f1/(f1+g1) increases by about 20%, while (f1+g1) remains unchanged. The D2O effect at the molecular level is discussed in connection with biochemical studies on actomyosin ATPase. 相似文献
185.
186.
We conducted line route censuses of fungal fruiting bodies from August to September in 2005 and 2006 along ridges and valleys
and compared the differences in the encounter rates of fungal fruiting bodies (= fruiting bodies seen per census kilometer)
between types of topography and between fungal functional groups (i.e., ectomycorrhizal and saprobic fungi) in warm temperate
evergreen broad-leaved forests on Yakushima Island, Japan. We found 251 fungal fruiting bodies (26 families, 50 genera, and
65 species) in total, including 51 bodies from Tricholomataceae, 41 from Russulaceae, 25 from Boletaceae, and 19 from Amanitaceae.
The encounter rate of ectomycorrhizal fungi was greater at the ridge route (26.7 unit/km) than at the valley route (8.7 unit/km)
and that of saprobic fungi was greater at the valley route (25.0 unit/km) than at the ridge route (12.5 unit/km). In addition,
we conducted 7-year intermittent sampling and identified 40 families, 96 genera, and 142 species. The topography-specific
emergence pattern of the intermittent sampling method was similar to that of the line census method. The fungal species composition
in this study was possibly affected by a topographic gradient for both fungal functional groups through soil moisture, nutrient
availability, and host tree distribution. 相似文献
187.
Complete Genome Structure of the Unicellular Cyanobacterium Synechocystis sp. PCC6803 总被引:2,自引:0,他引:2
Cyanobacteria are photoautotrophic organisms capable of oxygen-producingphotosynthesis similar to that in eukaryotic algae and plants,and because of this, they have been used as model organismsfor the study of the mechanism and regulation of oxygen-producingphotosynthesis. To understand the entire genetic system in cyanobacteria,the nucleotide sequence of the entire genome of the unicellularcyanobacterium Synechocystis sp. PCC6803 has been determined.The total length of the circular genome is 3,573,470 bp, witha GC content of 47.7%. A total of 3,168 potential protein codinggenes were assigned. Of these, 145 (4.6%) were identical toreported genes, and 1,259 (39.6%) and 342 (10.8%) showed similarityto reported and hypothetical genes, respectively. The remaining1,422 (45.0%) showed no apparent similarity to any genes registeredin the databases. Classification of the genes by their biologicalfunction and comparison of the gene complement with those ofother organisms have revealed a variety of features of the geneticinformation characteristic of a photoautotrophic organism. Thesequence data, as well as other information on the Synechocystisgenome, is presented in CyanoBase on WWW [http://www.kazusa.or.jp/cyano/]. (Received July 24, 1997; Accepted September 17, 1997) 相似文献
188.
Psychogenic fever is one of the most common psychosomatic diseases. In Japan, psychogenic fever has generally been reported
to occur in adolescents, with a peak seen at age 13. However, in our department we have encountered many adults with psychogenic
fever. Therefore, we investigated all outpatients who visited the Psychosomatic Department of the University of Occupational
and Environmental Health between April 2003 and March 2007. Of the 2705 outpatients that were seen, 55 patients (2.0%) were
diagnosed with psychogenic fever. The patients ranged in age from 11 to 82 years old, with a mean age of 33.6 ± 17.9 (mean
± SD) years. In addition to the adolescents, many of the patients were in their 20 s and 30 s, and the male:female ratio was
1:2.2. This study suggests that psychogenic fever commonly occurs not only in adolescents but also in adults. 相似文献
189.
Yuka Koyama Katsuyoshi Matsunami Hideaki Otsuka Takakazu Shinzato Yoshio Takeda 《Phytochemistry》2010,71(5-6):675-681
From a 1-BuOH-soluble fraction of a MeOH extract of the leaves of Microtropis japonica, collected in the Okinawa islands, six ent-labdane glucosides, named microtropiosides A–F, were isolated together with one known acyclic sesquiterpene glucoside. Their structures were elucidated by a combination of spectroscopic analyses, and their absolute configurations determined by application of the β-d-glucopyranosylation-induced shift-trend rule in 13C NMR spectroscopy and the modified Mosher’s method. 相似文献
190.
From specimens collected in the western North Pacific, the early ontogeny ofPsettina iijimae andLaeops kitaharae is described. Diagnostic characters of the genera throughout larval stages are also provided. It is suggested that these species are distributed on continental shelf or at the edge, and that they spawn between July and September. 相似文献