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961.
Phylogenetic analysis based on 18S rRNA gene and matK gene sequences of Panax vietnamensis and five related species 总被引:3,自引:0,他引:3
Panax vietnamensis was discovered recently in Vietnam. Its bamboo-like rhizomes, called Vietnamese Ginseng, have attracted considerable attention because of their specific pharmacological activities. In order to define the taxonomic position of this new species and include it in the molecular authentication of Ginseng drugs, the 18S ribosomal RNA gene and matK gene sequences of P. vietnamensis were determined and compared with those of its related taxa, P. japonicus var. major and P. pseudo-ginseng subsp. himalaicus, besides previously reported P. ginseng, P. japonicus and P. quinquefolius. The 18S rRNA gene sequences were found to be 1809 bps in length. The sequence of P. vietnamensis was identical to that of P. quinquefolius, and presented one base substitution from those of both P. japonicus var. major and P. pseudo-ginseng subsp. himalaicus. The matK gene sequences of 6 taxa were found to be 1509 bps in length. The sequence of P. vietnamensis differed from those of P. japonicus var. major, P. pseudo-ginseng subsp. himalaicus, P. ginseng, P. japonicus and P. quinquefolius at 4, 5, 9, 9 and 10 nucleotide positions, respectively. The phylogenetic tree reconstructed by the combined 18S rRNA-matK gene analysis using the maximum parsimony method showed that P. vietnamensis was sympatric with other Panax species and had a close relationship with P. japonicus var. major and P. pseudo-ginseng subsp. himalaicus. 相似文献
962.
Hypoglycemic agents with a rapid onset and short duration of action should be useful for controlling postprandial hyperglycemia. Our aim was to establish a diabetes mellitus model in dogs, and then during an oral glucose tolerance test to compare the hypoglycemic effect and insulinotropic action of KAD-1229, a new hypoglycemic agent, with that of gliclazide, a conventional sulfonylurea. In this model, KAD-1229 reduced the increase in plasma glucose level without producing hypoglycemia. Gliclazide had a weaker effect on reduction of the glucose increase and caused hypoglycemia via a significantly raised insulin secretion in the late phase. A rapid insulinotropic action of KAD-1229 was clearly observed in the portal venous blood. The results suggest that in type 2 diabetes caused by, at least, insulin deficiency, KAD-1229 may improve impaired insulin secretion in the early phase and attenuate hyperglycemia without causing a sustained hypoglycemia. 相似文献
963.
Moro M Inada Y Kojima M Miyata H Komatsu H Torii R 《European journal of pharmacology》1999,368(1):57-66
We aimed to develop an anovulation model, using sulpiride-induced hyperprolactinemia in common marmosets. The serum prolactin level gradually increased during the twice-daily administration of sulpiride and reached a plateau after 4 days. Sulpiride produced as big a response at 10 mg kg(-1) as at 50 mg kg(-1). In this study, the length of the ovarian cycle was approximately 30 days in normal common marmosets. Serum progesterone and estradiol levels showed no consistent change during the first 2 months of treatment with sulpiride. When treatment with sulpiride had been continued for more than 2 months, serum progesterone and estradiol levels fell to within the range seen in the follicular phase of the normal cycle and absence of ovulation was recognized by laparoscopy. A single oral administration of cabergoline (at doses between 0.01 and 0.1 mg kg(-1)) dose dependently reduced the elevated serum prolactin level. Bromocriptine (at an oral dose of 10 mg kg(-1)) also reduced the serum prolactin level at 4 and 8 h after its administration. With bromocriptine, the prolactin level had recovered at 24 h, but with cabergoline at doses of 0.05 mg kg(-1) or more, it had still not recovered at 48 h. In anovulatory common marmosets, oral administration of cabergoline at a daily dose of 0.05 mg kg(-1) restored ovarian function and resulted in ovulation in 100% of the group (following a reduction in the serum prolactin level). Bromocriptine at a daily oral dose of 10 mg kg(-1) resulted in ovulation in 67% of the group, but this dose was about 200 times higher than the dose of cabergoline. We could produce an anovulatory model induced by sulpiride repeatedly administered over a long time period. It is suggested that, in this anovulatory model in common marmosets, cabergoline has a potent and long-lasting action as a dopamine D2 receptor agonist, and thus could be a useful drug for the treatment of galactorrhea and hyperprolactinemic amenorrhea and/or anovulation. 相似文献
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967.
Y Koike H Imaizumi E Takahashi Y Matsubara H Komatsu 《The Tohoku journal of experimental medicine》1999,188(2):139-142
We conducted a retrospective study of the influence of various factors on the mortality of 114 patients with hip fractures. The mortality rate one year after surgery was 18%, which was 2.5 times larger than that of the general population. It was related to age, ECG abnormality, and post-operative complications. 相似文献
968.
In this paper, we describe a patient with transient osteoporosis of the femoral condyle. A differential diagnosis should be made for osteonecrosis, infectious disorders, and infiltrative neoplasms based on the normal laboratory findings and diffuse bone edema pattern in MRI. Since this disorder is self-limiting, both the surgeon and clinician should be aware of this condition and must avoid unnecessary intervention. 相似文献
969.
Tomoko Inoue Daisuke Sugiyama Ryo Kurita Tatsuo Oikawa Kasem Kulkeaw Hirotaka Kawano Yoshie Miura Michiyo Okada Youko Suehiro Atsushi Takahashi Tomotoshi Marumoto Hiroyuki Inoue Norio Komatsu Kenzaburo Tani 《Stem cell reviews》2011,7(1):43-52
The mechanism that regulates the terminal maturation of hematopoietic stem cells into erythroid cells is poorly understood. Therefore, identifying genes and surface markers that are restricted to specific stages of erythroid maturation will further our understanding of erythropoiesis. To identify genes expressed at discrete stages of erythroid development, we screened for genes that contributed to the proliferation and maturation of erythropoietin (EPO)-dependent UT-7/EPO cells. After transducing erythroid cells with a human fetal liver (FL)-derived lentiviral cDNA library and culturing the cells in the absence of EPO, we identified 17 candidate genes that supported erythroid colony formation. In addition, the mouse homologues of these candidate genes were identified and their expression was examined in E12.5 erythroid populations by qRT-PCR. The expression of candidate erythroid marker was also assessed at the protein level by immunohistochemistry and ELISA. Our study demonstrated that expression of the Apoa-1 gene, an apolipoprotein family member, significantly increased as hematopoietic stem cells differentiated into mature erythroid cells in the mouse FL. The Apoa-1 protein was more abundant in mature erythroid cells than hematopoietic stem and progenitor cells in the mouse FL by ELISA. Moreover, APOA-1 gene expression was detected in mature erythroid cells from human peripheral blood. We conclude that APOA-1 is a novel marker of the terminal erythroid maturation of hematopoietic stem cells in both mice and humans. 相似文献