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Yuko Kamio Yurika Saito Naoki Utoguchi Masuo Kondoh Naoya Koizumi Makiko Fujii Yoshiteru Watanabe 《Journal of controlled release》2005,102(3):563-568
Some physiological substances, including acetylcholine and nitric oxide, are useful candidates for stimulation of intestinal absorption of drugs. In the present study, we elucidated the ability of epinephrine (Epi) to stimulate the intestinal absorption of drugs. We evaluated the ability of Epi to enhance absorption of macromolecules using dextran (Mw 4000 Da), which is poorly absorbed from the intestine, as a model compound in situ in a closed loop of the rat jejunum. Treatment of the jejunum with Epi resulted in significant increase in absorption of dextran in a dose-dependent fashion. The area under the curve (AUC) from 0 to 4 h in the Epi-treated jejunum was 13-fold higher than that in the vehicle-treated jejunum. The absorption-enhancing activity of Epi was 40-fold higher than that of caprate, a clinically used absorption-enhancer of drugs. In the experimental conditions used in this study, histological injury of the mucosa and perturbation of the mucosal membrane were not observed in the Epi-treated jejunum. Treatment with an antagonist of alpha-adrenergic receptors attenuated the stimulation of intestinal absorption by Epi, and treatment with an agonist of alpha-adrenergic receptors resulted in enhancement of intestinal absorption. While an antagonist of beta-adrenergic receptors enhanced the absorption-enhancing effect of Epi, an agonist of beta-adrenergic receptors stimulated intestinal absorption. These results indicate that stimulation of adrenergic receptors may be a novel strategy for intestinal absorption of drugs. 相似文献
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S. Hashitani K. Sakurai K. Noguchi J. Natori M. Urade 《Journal of oral pathology & medicine》2004,33(1):59-63
A rare case of mucinous adenocarcinoma with neuroendocrine differentiation of the mandibular ramus is presented. The patient, an 80-year-old man, was referred to our hospital with chief complaint of swelling and pain in the left buccal mucosa. CT and MRI examination showed an osteolytic tumor mass occupying the upper region of the left mandibular ramus. Macroscopically, the excised tumor was a relatively well-defined, solid mass with diffuse bone resorption, measuring 3 cm x 3.2 cm x 3 cm. Microscopical examination showed that the tumor forming glandular structures with abundant mucous production and high cellular atypia. Immunohistochemical studies demonstrated the positive reactivities for pan-keratin, cytokeratin 7, vimentin,alpha-amylase, alpha-smooth muscle actin, neuron-specific enolase, glial fibrillary acid protein, calcitonin, and somatostatin in tumor cells. These findings suggested that the tumor was originated from heterotopic or misplaced salivary gland in the mandible. 相似文献
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Toshihiro Kawamura Hiroshi Motoyama Atsushi Yanaihara Takeshi Yorimitsu Akane Arichi Yasuhiro Karasawa Kahori Suga Kaoru Miya Seika Ishikawa Shiho Mizushima Makiko Kawamura 《Reproductive Medicine and Biology》2007,6(1):53-57
Aim: To compare the clinical outcomes of cryopreserved-thawed embryo transfer among patients with a normal menstrual cycle who had natural or hormone-replacement cycles.
Methods: From January 2004 to June 2006, cryopreserved embryos following conventional in vitro fertilization (IVF) or intracytoplasmic sperm injection (ICSI) were thawed and transferred in a total of 720 natural cycles and 136 hormone-replacement cycles.
Results: Cryopreserved-thawed embryo transfer in patients who had a natural or hormone-replacement cycle resulted in clinical pregnancy in 43.1% and 40.4%, respectively; a rate of miscarriage of 14.5% and 23.6%, respectively; and a rate of ongoing pregnancy and delivery of 36.5% and 30.9%, respectively. None of these differences were statistically significant.
Conclusions: Patients with a normal menstrual cycle who have natural or hormone-replacement cycles can be expected to have comparable clinical outcomes with cryopreserved-thawed embryo transfer. (Reprod Med Biol 2007; 6 : 53–57) 相似文献
Methods: From January 2004 to June 2006, cryopreserved embryos following conventional in vitro fertilization (IVF) or intracytoplasmic sperm injection (ICSI) were thawed and transferred in a total of 720 natural cycles and 136 hormone-replacement cycles.
Results: Cryopreserved-thawed embryo transfer in patients who had a natural or hormone-replacement cycle resulted in clinical pregnancy in 43.1% and 40.4%, respectively; a rate of miscarriage of 14.5% and 23.6%, respectively; and a rate of ongoing pregnancy and delivery of 36.5% and 30.9%, respectively. None of these differences were statistically significant.
Conclusions: Patients with a normal menstrual cycle who have natural or hormone-replacement cycles can be expected to have comparable clinical outcomes with cryopreserved-thawed embryo transfer. (Reprod Med Biol 2007; 6 : 53–57) 相似文献
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Microsurgical and magnetic resonance imaging anatomy of the cerebello-medullary fissure and its application during fourth ventricle surgery. 总被引:3,自引:0,他引:3
The cerebellomedullary fissure, the only entrance or exit to the fourth ventricle, is surrounded rostrally by the cerebellar tonsils and the biventral lobules and caudally by the medulla oblongata, the tela choroidea, and the lateral recesses. This fissure is an important route in operations on the fourth ventricle. We studied the microsurgical and magnetic resonance imaging (MRI) anatomy of the fissure by using autopsied normal cerebellum. MRI revealed that the fissure is visible as a slit and is indicated by the enhanced choroid plexus and the flocculus. Oriented by the anatomical information thus obtained, we have surgically treated nine patients with a tumor either in or around the fourth ventricle. Preoperative MRI clearly demonstrated the tumors in relation to the cerebellomedullary fissure. It revealed the precise anatomical location and extension of the tumor, not only its inferior extension but also its lateral one. The MRI findings and microsurgical anatomy of the cerebellomedullary fissure were quite useful for the removal of the tumors in the fourth ventricle. 相似文献
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Terashima Y Onai N Murai M Enomoto M Poonpiriya V Hamada T Motomura K Suwa M Ezaki T Haga T Kanegasaki S Matsushima K 《Nature immunology》2005,6(8):827-835
Ligation of the chemokine receptor CCR2 on monocytes and macrophages with its ligand CCL2 results in activation of the cascade consisting of phosphatidylinositol-3-OH kinase (PI(3)K), the small G protein Rac and lamellipodium protrusion. We show here that a unique clathrin heavy-chain repeat homology protein, FROUNT, directly bound activated CCR2 and formed clusters at the cell front during chemotaxis. Overexpression of FROUNT amplified the chemokine-elicited PI(3)K-Rac-lamellipodium protrusion cascade and subsequent chemotaxis. Blocking FROUNT function by using a truncated mutant or antisense strategy substantially diminished signaling via CCR2. In a mouse peritonitis model, suppression of endogenous FROUNT markedly prevented macrophage infiltration. Thus, FROUNT links activated CCR2 to the PI(3)K-Rac-lamellipodium protrusion cascade and could be a therapeutic target in chronic inflammatory immune diseases associated with macrophage infiltration. 相似文献
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