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排序方式: 共有3861条查询结果,搜索用时 15 毫秒
1.
Kota Sahara Rin Yamada Takashi Fujiwara Koichi Koizumi Shin‐ichiro Horiguchi Tsunekazu Hishima Tatsuro Yamaguchi 《Digestive endoscopy》2015,27(7):768-771
Idiopathic myointimal hyperplasia of mesenteric veins (IMHMV) is a rare and poorly understood ischemic colitis that occurs in the rectosigmoid colon of predominantly young, previously healthy, male patients. A 76‐year‐old Japanese man presented to our hospital with a 1‐year history of worsening diarrhea, lower abdominal pain, and weight loss (−6 kg). Laboratory evaluation revealed white blood cell count of 13 200/μL, C‐reactive protein level of 2.0 mg/dL (normal range, 0.0–0.3), and negative results for stool culture (including Clostridium difficile). Colonoscopy showed circumferential and edematous narrowing of the sigmoid colon with deep longitude ulceration. Biopsy was done and examination of the specimen demonstrated no specific ischemia. The patient was treated with bowel rest, antibiotics, and i.v. fluids; however, his symptoms worsened. Finally, sigmoidectomy was carried out. Histological examination demonstrated significant myointimal hyperplasia of mesenteric veins leading to thickening and stenosis of the venous lumen. Therefore, the final diagnosis was IMHMV. Three months following sigmoidectomy, he was asymptomatic. 相似文献
2.
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
3.
Mikihiko Kudo Takahiko Misumi Kiyoshi Koizumi Hankei Shin 《Annals of thoracic and cardiovascular surgery》2005,11(2):121-124
A 78-year-old woman with diagnosis of acute myocardial infarction (AMI) in the anteroseptal area fell into cardiogenic shock suddenly just before starting percutaneous coronary intervention (PCI). Echocardiography showed left ventricular free wall rupture, then an emergent operation was performed by sutureless patch repair using collagen fleece with fibrinogen-based impregnation. Eight days later from the initial operation, the onset of ventricular septal perforation (VSP) was recognized. Fifteen days after, the infarct exclusion technique with endocardial patch was performed. She has been doing well 4 months after the operation without residual shunt. To our best knowledge, this is the first surgical case report that free wall rupture of left ventricle and VSP which are serious complications after myocardial infarction happened in succession. 相似文献
4.
Masanori Honma Yumiko Hayakawa Hiromi Kosugi Fumitomo Koizumi 《Journal of oral pathology & medicine》1998,27(8):399-404
The expression of mRNA encoding the inflammatory cytokines interleukin-1α (IL-1α), interleukin-1β (IL-1β), interleukin-6 (IL-6), interleukin-8 (IL-8) and tumor necrosis factor α (TNF-α) have been examined in radicular cysts by in situ hybridization. Furthermore, the biological activity of the contents of radicular cysts (RCC) has been assayed by adding extracts of RCC to cultured human gingival fibroblasts (HGFs) and analyzing the culture medium for the release of inflammatory cytokines. In the epithelial layer, keratinocytes expressed all cytokine mRNAs examined at various levels. Basal layer cells expressed mRNA for each cytokine. In the subepithelial granulation tissue of the cysts, fibroblasts and macrophages expressed mRNA for IL-6, IL-8, IL-1β and TNF-α mRNA at varying levels; especially clear expression of TNF-α and IL-1β mRNA was detected on macrophages. The infiltrating lymphoid cells, largely composed of T cells and plasma cells, expressed these cytokine mRNAs, especially those encoding IL-6 and IL-8, at various levels. In vitro analysis indicated dose-dependent release of both IL-6 and IL-8 by HGFs in response to RCC. After heating to 100°C for 10 min, RCC almost completely failed to stimulate IL-6 release from HGFs. Furthermore, anti-IL-1β antibody (neutralization test) did not prevent the stimulation of IL-6 release by RCC. Significant amounts of IL-6 and IL-8 were detected in RCC in two cases, and a trace amount of IL-1β was detected in one case. This study demonstrated the wide expression of mRNA encoding inflammatory cytokines in radicular cyst tissues, and RCC itself was capable of stimulating 1L-6 and 1L-8 production from HGFs. 相似文献
5.
6.
We investigated the effects of energy restriction on the pituitary-ovarian axis and on a hormone responsive gene, the mouse mammary tumor virus (MMTV). Female C3H/SHN F1-hybrid mice, known to display a high incidence of mammary tumors, ate an energy-restricted diet (48 kcal/wk) or a control diet (95 kcal/wk) beginning at the time of weaning. By 67 wk of age, 12 of 32 mice in the control group, but none of the 33 mice in the energy-restricted group, had developed mammary tumors. Six tumor-free mice from each group were studied in detail at 67 wk of age. All six tumor-free control mice, but none of the six energy-restricted mice, showed uterine endometrial hyperplasia at autopsy. Mice subjected to energy restriction did not display an estrous cycle. The average levels of MMTV mRNA in mammary glands and uteri were strongly reduced by energy restriction. MMTV mRNA levels in mammary glands from control mice were two orders of magnitude lower than those in mammary tumors. Energy restriction lowered the percentage of pituitary mammatropes and suppressed proliferation of mammatropes with advancing age. Energy restriction thus appeared to inhibit endometrial hyperplasia and to decrease MMTV production at the mRNA level in the mammary glands and in the uterus. These effects may be a consequence of hormonal changes originating at the pituitary-ovarian axis. 相似文献
7.
Expression of β-catenin was investigated in normal breast tissue and 66 breast carcinomas in conjunction with expression of epithelial cadherin (E-CD) and α-catenin. In normal mammary ducts and acini, intense β-catenin immunoreactivity was present at the basolateral surfaces of luminal epithelium and weak immunoreactivity was observed at the lateral borders of myoepithelial cells. No β-catenin was revealed at the myoepithelial basal surface. The intercellular expression of β-catenin, as well as of E-CD and α-catenin, was also observed in carcinoma tissues with varying staining intensity. Almost all of 10 intraductal carcinomas and approximately 70% of 41 invasive ductal carcinomas expressed the three molecules at the same level as in normal glands, whereas approximately 80% of 13 invasive lobular carcinomas showed severe deficiency of them. Two lobular carcinomas in situ showed complete absence of all of the proteins. Some of these findings were confirmed biochemically by immunoblotting analysis. In invasive ductal carcinomas, α-catenin was reduced more frequently in diffuse than in solid type tumours, whereas the level of expression of β-catenin and E-CD was unchanged between them. No correlation was present between reduced expression of the adhesion molecules and lymph node metastasis. 相似文献
8.
A Usuba R Motoki Y Koizumi A Oishi Y Endo O Konno H Inoue 《Nihon Geka Gakkai zasshi》1990,91(8):931-941
Hypercoagulability develops after surgery for esophageal carcinoma, and it related closely to postoperative complications. This study evaluated the effects of the synthetic proteinase inhibitor, Cabexate Mesilate (FOY), on this hypercoagulability. The subjects used were 25 patients with a mean age of 63 who had undergone surgery for esophageal carcinoma. Of these, eight patients (test group) received FOY (2,000 mg/day) for three to 23 days after surgery, but 17 (control group) did not. In the test group, FOY controlled aggregation and release of the platelets and minimized their exhaustion. FOY almost completely checked the abnormal increase in thrombin activity which might trigger the hypercoagulability. Also, FOY suppressed the fibrinolytic activity slightly. These results indicate that FOY is effective in controlling hypercoagulability after surgery for esophageal carcinoma and in suppressing activity of the proteinases that cause both blood coagulation and fibrinolysis. 相似文献
9.
-Hydroperoxy diethyl peroxide, a novel compound found in the tunic of ascidians, has two peroxide moieties per molecule. Since ascidians are a widely served food item in Japan, human exposure to this compound potentially exists in the seafood preparation industries. No toxicological data have so far been published on this compound, and so we determined the intraperitoneal 6-day LD50 in mice and conducted histopathological examinations. The 6-day LD50, was found to be 199 mg/kg with 95% confidence limits of 126–314 mg/kg. Histopathological examination revealed necrosis induced in a variety of cells that had been directly exposed to the compound. These cells included hepatocytes, parenchymal pancreatic cells and fat cells. It is concluded that direct contact with this compound is likely to elicit cellular necrosis of various organs. The specific toxicological effects are probably dependent on the route of exposure. 相似文献
10.
N Sakai K Sawada K Koizumi T Tarumi N Sato M Ieko S Sakurama T Yasukouchi Y Matsunaga 《[Rinshō ketsueki] The Japanese journal of clinical hematology》1992,33(8):1077-1083
A 30-year-old female at 27 weeks' gestation, was hospitalized on September 24 1990 because of the premature rupture of the amniotic sac. She underwent Caesarean section on the same day with 700 ml blood loss, but no blood transfusion was required. For several days after the operation, her hemoglobin level remained 7.8 g/dl and did not increase significantly in spite of parenteral iron therapy. On the 9th postoperative day, chills and pyrexia developed with leukopenia. Bone-marrow aspiration revealed severe erythroblastopenia with giant proerythroblasts, suggesting recent HPV infection, which was confirmed by the presence of anti-HPV IgM and HPV antigen by ELISA. The hemoglobin level gradually decreased to 6.0 g/dl by the 21st day, then began to increase rapidly. The serum of acute-phase containing HPV antigens inhibited BFU-E and CFU-E but not CFU-GM. The serum of convalescent-phase inhibited neither erythroid colony growth nor myeloid colony growth. These results indicate that the inhibitory effect of HPV in colony assay is highly specific for erythropoiesis and that HPV play a role in transient cessation of erythropoiesis. The reason, however, for leukopenia in HPV infection remained unclear. This case shows that HPV infection may induce severe hematological disorders even in normal person under erythropoietic stress. 相似文献