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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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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   
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Recent progress in molecular biology suggests a certain relationship between penile cancer and human papilloma virus infection. However, the treatment for penile cancer has not been established since each institute has experienced only a small number of patients. We analyzed the result of our treatment for 14 penile cancer patients during past twenty years. Ten of the 14 patients were initially treated for the primary lesion with a combination of peplomycin (PEP) or bleomycin (BLM) and radiation therapy. Of these, 9 were found not to have residual viable cancer cells in their primary lesions. No local recurrence was found in all 7 patients in whom the penis was preserved. This result suggests that combination of PEP (BLM) and radiation preserves the penis without increasing the risk of local recurrence. Penile cancer-related death did not occur in patients without lymph node metastasis. However, this cancer death did occur in 4 out of 7 patients with lymph node metastasis, suggesting that metastasis is one of the important prognostic factors. PEP (BLM) and radiation therapy with or without regional lymph node dissection did not improve the prognosis of patients with advanced penile carcinoma, such as with pN2, pN3 or distant metastasis. More effective management may be necessary for these patients.  相似文献   
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A composite nasolabial flap for an entire ala reconstruction.   总被引:3,自引:0,他引:3  
BACKGROUND: It is difficult to reconstruct an entire alar defect. We report a case of an entire alar reconstruction carried out in two stages with a composite nasolabial flap lined with retroauricular skin and supported with the attached conchal cartilage. OBJECTIVE: A composite nasolabial flap was applied for reconstruction of entire alar defect in this patient. METHODS: The lining skin for the flap was obtained from retroauricular region acceptable to the patient, and the conchal cartilage was used simultaneously for support and as the attachment for the lining skin. The flap was then replaced and secured. Half a year later, the flap was flipped and transferred to the alar defect as a second step. RESULTS: The final shape and texture were satisfactory. All procedures were performed under local anesthesia. CONCLUSION: Our design of composite flap has been successfully utilized to repair an entire alar defect with cosmetically and functionally good results, minimizing the donor area and the resulting operation scars. This composite nasolabial flap is thought to be the best choice of a flap for an entire alar defect reconstruction.  相似文献   
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Summary BS compounds, a series of new dihydropyridines, successfully overcame multidrug resistance in P388/ADR cells in vitro. These agents synergistically potentiated the cytotoxicity of Adriamycin to P388/ADR cells at a concentration of 1–2 M, whereas they showed hardly any synergistic effect in the parental cell line (P388/S) at the same concentration. They inhibited the active drug efflux in P388/ADR cells as well as the binding of [G-3H]-vinblastine to membrane vesicles from P388/ADR, which was increased in resistant P388 cells as compared with parental cells. Besides, unlike the activity of clinically used calcium antagonists, the calcium antagonistic activity associated with BS compounds was very weak: their arterial relaxation activity was <21% of that of verapamil. These data suggest that BS compounds specifically overcome multidrug resistance without the serious hypotensive side effects that accompany the use of verapamil orother calcium antagonists.  相似文献   
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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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Genetic contributions to the etiology of substance abuse and dependence are topics of major interest. Acute and chronic cannabis use can produce drug-induced psychosis resembling schizophrenia and worsen positive symptoms of schizophrenia. The endocannabinoid system is one of the most important neural signaling pathways implicated in substance abuse and dependence. The fatty acid amide hydrolase (FAAH) is a primary catabolic enzyme of endocannabinoids. To clarify a possible involvement of FAAH in the etiology of methamphetamine dependence/psychosis or schizophrenia, we examined the genetic association of a nonsynonymous polymorphism of the FAAH gene (Pro129Thr) by a case-control study. We found no significant association in allele and genotype frequencies of the polymorphism with either disorder. Because the Pro129Thr polymorphism reduces enzyme instability, it is unlikely that dysfunction of FAAH and enhanced endocannabinoid system induce susceptibility to either methamphetamine dependence/psychosis or schizophrenia.  相似文献   
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