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91.
Changes in eicosapentaenoic acid content of Navicula saprophila, Rhodomonas salina and Nitzschia sp. under mixotrophic conditions 总被引:4,自引:0,他引:4
Three species of microalgae able to produce eicosapentaenoic acid(EPA) were collected from brackish and sea water around Japan.
The species were identified as Navicula saprophila, Rhodomonassalina and Nitzschia sp. EPA as a proportion of total fatty
acids increased in the presence of acetic acid for Rhodomonas salina and Nitzschia sp. However, Navicula saprophila displayed
the greatest productivity of EPA and the EPA content of its biomass was enhanced under mixotrophic conditions in the presence
of acetic acid.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
92.
Does endothelin-1 participate in the exercise-induced changes of blood flow distribution of muscles in humans? 总被引:1,自引:0,他引:1
Maeda Seiji; Miyauchi Takashi; Sakane Michiko; Saito Makoto; Maki Shinichi; Goto Katsutoshi; Matsuda Mitsuo 《Journal of applied physiology》1997,82(4):1107-1111
Maeda, Seiji, Takashi Miyauchi, Michiko Sakane, MakotoSaito, Shinichi Maki, Katsutoshi Goto, and Mitsuo Matsuda. Does endothelin-1 participate in the exercise-induced changes of blood flowdistribution of muscles in humans? J. Appl.Physiol. 82(4): 1107-1111, 1997.Endothelin-1(ET-1) is an endothelium-derived potent vasoconstrictor peptide thatpotentiates contractions to norepinephrine in human vessels. Wepreviously reported that the circulating plasma concentration of ET-1is significantly increased after exercise (S. Maeda, T. Miyauchi, K. Goto, and M. Matsuda. J. Appl.Physiol. 77: 1399-1402, 1994). Tostudy the roles of ET-1 during and after exercise, we investigatedwhether endurance exercise affects the production of ET-1 in thecirculation of working muscles and nonworking muscles. Male athletesperformed one-leg cycle ergometer exercise of 30-min duration atintensity of 110% of their individual ventilatory threshold. Plasmaconcentrations of ET-1 in both sides of femoral veins (veins in theworking leg and nonworking leg) and in the femoral artery (artery inthe nonworking leg) were measured before and afterexercise. The plasma ET-1 concentration in the femoralvein in the nonworking leg was significantly increased after exercise,whereas that in femoral vein in the working leg was not changed. Thearteriovenous difference in ET-1 concentration was significantlyincreased after exercise in the circulation of the nonworking leg butnot of the working leg, which suggests that the production of ET-1 wasincreased in the circulation of the nonworking leg by exercise. Thepresent study also demonstrated that the plasma norepinephrineconcentrations were elevated by exercise in the femoral veins of boththe working and nonworking legs, suggesting that the sympathetic nerveactivity was augmented in both legs during exercise. Therefore, thepresent study demonstrates the possibility that the increase inproduction of ET-1 in nonworking muscles may cause vasoconstriction andhence decrease blood flow in nonworking muscles through its directvasoconstrictive action or through an indirect effect of ET-1 toenhance vasoconstrictions to norepinephrine and that these responsesmay be helpful in increasing blood flow in workingmuscles. We propose that endogenous ET-1 contributes tothe exercise-induced redistribution of blood flow in muscles. 相似文献
93.
Makoto Matsuoka Masanori Tamaoki Yuichi Tada Tatsuhito Fuyjimura Akemi Tagiri Naoki Yamamoto Yuriko Kano-Murakami 《Plant cell reports》1995,14(9):555-559
Transgenic rice plants (Oryza sativa cv. Nipponbare) carrying 1 or 2 copies of a rice homeobox gene, OSH1, under the control of the CaMV 35S promoter were generated. The transgene caused altered morphology of leaf, such as ligule-replacement and abnormal division of sclerenchyma cells. The phenotype of these leaves resembles that of maize leaf morphological mutant, Knotted 1, which is caused by duplication of the KN1 gene (Veit et al., 1990). The in situ hybridization analysis has revealed that the expression of endogenous OSH1 is mainly localized in developing vascular strands of stem. We have discussed the biological roles of OSH1 in rice based on these results. 相似文献
94.
Summary The parameters for HN chemical shift calculations of proteins have been determined using data from high-resolution crystal structures of 15 proteins. Employing these chemical shift calculations for HN protons, the observed secondary structure chemical shift trends of HN protons, i.e., upfield shifts on helix formation and downfield shifts on -sheet formation, are discussed. Our calculations suggest that the main reason for the difference in NH chemical shifts in helices and sheets is not an effect from the directly hydrogen-bonded carbonyl, which gives rise to downfield shifts in both cases, but arises from an additional upfield shift predicted in helices and originating in residues i-2 and i-3. The calculations also explain the well-known relationship between amide proton shifts and hydrogen-bond lengths. In addition, the HN chemical shifts of the distorted amphipathic helices of the GCN4 leucine zipper are calculated and used to characterise the solution structure of the helices. By comparing the calculated and experimental shifts, it is shown that in general the agreement is good between residues 15 and 28. The most interesting observation is that in the N-terminal half of the zipper, although both calculated and experimental shifts show clear periodicity, they are no longer in phase. This suggests that for the N-terminal half, in the true average solution structure the period of the helix coil is longer by roughly one residue compared to the NMR structures. 相似文献
95.
Low-humidity treatment triggered an increase of the thallus area and the chlorophyll content in the following high-humidity
condition. When low-humidity treatment for 4 days was intercalated in high-humidity conditions every 16 days, the thallus
area increased 40% in 76 days. 相似文献
96.
This paper describes six species of permineralized pinoid woods with resin canals from the Upper Cretaceous of Hokkaido, Japan
and Saghalien:Piceoxylon transiens Shimakura,P. scleromedullosum Shimakura,P. macroporosum sp. nov.,P. takahashii sp. nov.,Pinuxylon microporosum Ogura andPinoxylon dakotense (Knowlton) Read (new to Saghalien and the Cretaceous).Piceoxylon macroporosum is characterized by large resin canals and rays without ray tracheids and in lacking tylosoids in resin canals.Piceoxylon takahashii, which resemblesP. scleromedullosum, is distinguished from the latter in having ray tracheids and nests of sclereids in pith.
Structure and affinities of the petrified plants from the Cretaceous of Northern Japan and Saghalien XVI. (continued from
Ohsawaet al. 1995) 相似文献
97.
A new specimen of an araucarian cone,Araucaria nihongii, was found attached to the vegetative organs ofYezonia vulgaris, and is described asAraucaria vulgaris comb. nov. Thick branches show characteristic bark structure with lenticular patches. Secondary wood is usually araucarioid.
Leaves are arranged helically on shoots, which are imbricate, appressed and fused to surface of the stem. External and anatomical
features of leaves closely resembleBrachyphyllum. The seed cone is spherical with winged bracts and thin ovuliferous scales. One seed is borne per cone-scale complex. The
seed coat and nucellus wall show typical araucarian structure. An araucarian plant that boreBrachyphyllum-like foliage and aEutacta-like seed cone was predicted by Harris in 1979. This reconstructed plant,Araucaria vulgaris, supports this theory and proves the presence of an extinct characteristic-form of the genus. A new section of the genus
was proposed forAraucaria vulgaris.
Structure and Affinities of the Petrified Plants from the Cretaceous of Northern Japan and Saghalien XV, Consecutive number
from previous paper (Nishidaet al. 1993). 相似文献
98.
Dendrocacalia crepidifolia Nakai (Compositae, Senecioneae), the only species of this arboreal genus endemic to Haha Island in the Bonin Islands, was
found to be dioecious. Male flowers differ from female ones in having a stunted style (style in female exserted from corolla
and deeply bifurcating) and anthers filled with fertile pollen (anthers in the female lacking pollen). The size of the corolla
and number of florets per head were similar between male and female flowers. The crown area of this arboreal species was also
similar in male and female plants. The sex ratio was 0.55 male, not significantly different from 0.5. Both sexes produced
nectar of similar sugar concentration (ca. 50%). The flowers are pollinated by feral honeybees (Apis mellifera), but they are thought to have been pollinated by small, lesshairy, endemic solitary bees before honeybees were introduced
and subsequently became the dominant bee species on the island. The evolution of dioecy ofDendrocacalia on the island is thought to stem from the deleterious effects of inbreeding that are inherent in plants with geitonogamy.
The increased geitonogamy on the island has resulted from increased woodiness (i.e., increased number of flowers per plant)
and the original dependence on endemic bee pollinators, which are now endangered. 相似文献
99.
Mitsuyo Okazaki Makoto Kinoshita Chikayuki Naito Ichiro Hara 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》1984,336(1)
A simple and rapid method for apolipoprotein analysis in serum high-density lipoproteins (HDL) has been developed using high-performance liquid chromatography (HPLC) with sodium phosphate buffer (pH 7.0) containing 0.1% sodium dodecyl sulphate (SDS) as eluent. In contrast to the use of urea solution as an eluent, apolipoproteins can be analysed by applying an incubation mixure of HDL and the eluent buffer. A TSK-GEL column of G3000SW was found to be more profitable than G2000SW or G4000SW for analysis of HDL apolipoproteins. Elution patterns monitored by absorbance at 280 nm using a G3000SW column can give precise quantitative as well as qualitative information about apolipoproteins of molecular weight between 104 and 105. HPLC patterns of HDL apolipoproteins were compared between individual human subjects with various diseases. Elution profiles for lipid components in an incubation mixture were also examined. 相似文献
100.