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1.
Norio Ohashi Masahiro Fukuhara Masahiko Shimada Akira Tamura 《FEMS microbiology letters》1995,125(2-3):299-304
Abstract The 16S rRNA gene sequences of Rickettsia tsutsugamushi and Rickettsia sibirica were determined by PCR and DNA sequencing. Phylogenetic analysis revealed that R. sibirica is positioned in a cluster of the genus Rickettsia with a similarity value of 98.1–99.6%, whereas R. tsutsugamushi is located apart from the cluster with a similarity value of 90.2–90.6%. This evidence suggests that R. tsutsugamushi should be excluded taxonomically from the genus Rickettsia . The phylogenetic classification of six antigenic variants in R. tsutsugamushi moderately reflected their antigenic relationship known in closely and distantly related strains. 相似文献
2.
Based on its proven anabolic effects on bone in osteoporosis patients, recombinant parathyroid hormone (PTH1-34) has been evaluated as a potential therapy for skeletal repair. In animals, the effect of PTH1-34 has been investigated in various skeletal repair models such as fractures, allografting, spinal arthrodesis and distraction
osteogenesis. These studies have demonstrated that intermittent PTH1-34 treatment enhances and accelerates the skeletal repair process via a number of mechanisms, which include effects on mesenchymal
stem cells, angiogenesis, chondrogenesis, bone formation and resorption. Furthermore, PTH1-34 has been shown to enhance bone repair in challenged animal models of aging, inflammatory arthritis and glucocorticoid-induced
bone loss. This pre-clinical success has led to off-label clinical use and a number of case reports documenting PTH1-34 treatment of delayed-unions and non-unions have been published. Although a recently completed phase 2 clinical trial of PTH1-34 treatment of patients with radius fracture has failed to achieve its primary outcome, largely because of effective healing
in the placebo group, several secondary outcomes are statistically significant, highlighting important issues concerning the
appropriate patient population for PTH1-34 therapy in skeletal repair. Here, we review our current knowledge of the effects of PTH1-34 therapy for bone healing, enumerate several critical unresolved issues (e.g., appropriate dosing regimen and indications)
and discuss the long-term potential of this drug as an adjuvant for endogenous tissue engineering. 相似文献
3.
4.
Masahiko Endo Zensaku Yosizawa 《Biochimica et Biophysica Acta (BBA)/General Subjects》1975,404(2):274-280
Uterine slices obtained from the estrogen-treated rabbits were digested with pronase. Glycosaminoglycans and acidic glycopeptides were then isolated by Dowex 1 column chromatography and preparative electrophoresis on celulose acetate membrane (Separax), in succession.Each subfraction thus obtained was identified by the mobility on Separax electrophoresis and the digestibility with mucopolysaccharidases (Streptomyces hyaluronidase, testicular hyaluronidase, chondroitinase AC, chondroitinase ABC and heparinase). The resulting data showed that each complex saccharide (hyaluronic acid, heparan sulfate, chondroitin sulfate A, chondroitin sulfate C, dermatan sulfate, sulfated glycopeptide and sialoglycopeptide) was separated into 2–5 fractions, indicating charge and/or molecular heterogeneity of each complex saccharide. 相似文献
5.
Latitudinal comparison of altitudinal changes in forest structure,leaf-type,and species richness in humid monsoon Asia 总被引:10,自引:0,他引:10
M. Ohsawa 《Plant Ecology》1995,121(1-2):3-10
A new template for mountain vegetation zonation along latitudinal gradients is proposed for examining geographical pattern of various forest attributes in humid monsoon Asia. The contrasting temperature regime in tropical and temperate mountains, i.e., the former is a non-seasonal, temperature-sum controlled environment, and the latter is a seasonal, low temperature limiting environment, leads to different altitudinal patterns of tree height distribution and species richness. In the tropical mountains, both tree height and species richness decrease steeply, and the tree height often stepwise. The decline of tree height and species diversity in the temperate mountains is far less pronounced except near the forest limit. Both trends are explained by their temperature regime. 相似文献
6.
Ayumi Fujisawa Takaharu Abe Ikuro Ohsawa Kouichi Kamogawa Yoshikazu Izumi 《FEMS microbiology letters》1993,110(1):1-4
Abstract Potassium-limited cultures of Candida utilis grown with ammonium chloride as the sole nitrogen source attained a higher dry weight than similar cultures grown with sodium nitrate as the sole nitrogen source. This increase depended on the extracellular ammonia concentration and was not due to accumulation of storage polymers. We conclude that in this yeast ammonium ions can fulfill to some extent the physiological role of potassium ions and that the intracellular concentration of ammonium ions is predominantly determined by the ammonia concentration in the culture medium. 相似文献
7.
8.
Takashi Saitoh Jon Olav Vik Nils Chr. Stenseth Toshikazu Takanishi Shintaro Hayakashi Nobuo Ishida Masaaki Ohmori Toshio Morita Shigeru Uemura Masahiko Kadomatsu Jun Osawa Koji Maekawa 《Population Ecology》2008,50(2):159-167
We analysed the effects of Quercus crispula acorn abundance on the density dependence of the large Japanese wood mouse Apodemus speciosus using time series data (1992–2007). The data were obtained in a forest in northern Hokkaido, Japan, by live-trapping rodents
and directly counting acorns on the ground. Acorn abundance in one year clearly influenced the abundance of wood mice in the
following year in all models examined based on the Gompertz and Ricker model; in addition, the abundance of wood mice had
effects on the population. Acorn abundance influenced the strength of density dependence (intraspecific competition) of the
wood mouse population. When the abundance of acorns was high, density dependence was relaxed, and as a result the equilibrium
density at which the population growth rate decreased to zero became higher. Those effects of acorn abundance were regarded
as a nonlinear perturbation effect (sensu Royama 1992). The nonlinearity of density dependence was also detected; higher densities had stronger effects on population growth rates.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
9.
10.
Lactobacillus casei YIT 9018 (LC 9018) augmented the natural killer (NK) cell activity of spleen cells from inbred BALB/c mice injected intravenously with LC 9018 or intraperitoneally with polyinosinate-polycytidylate. Augmentation of this activity by LC 9018 was also observed in male C3H/He, CBA/N, and C57BL/6 mice. The spleen cells exhibited no cytolytic activity against P815, a cell line insensitive to NK cells. The cytolytic activity of the spleen cells increased 2 days after the injection of 250 μg of LC 9018/mouse, peaked on day 3, and gradually declined thereafter. The increase caused by LC 9018 was also observed in normal and Meth A-bearing mice. In vitro treatment with anti-asialo GM1 antibody plus complement completely-abrogated the LC 9018-augmented murine NK cell activity. The NK activity on the 3rd day after LC 9018 injection was reduced by in vitro treatment with anti-Thy 1.2 monoclonal antibody plus complement to half of that observed when treatment was with complement alone. This suggests that there were two populations of NK cells in the spleen cell suspension derived from LC 9018-treated mice. One population was asialo GM1-positive and Thy 1-negative, the other was asialo GM1-positive and Thy 1-positive. 相似文献