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1.
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   
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A 50-year-old Japanese man had a blue-black patch on the dorsum of his right wrist. Light and electron microscopic study of the lesion revealed dermal melanocytes containing mature melanosomes, predominantly in the upper dermis. This case was diagnosed as acquired dermal melanocytosis confined to the right wrist.  相似文献   
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PURPOSE: The purpose of this study was to examine changes of chewing movement and masticatory efficiency during the natural course of nonreducing disc displacement of the temporomandibular joint (TMJ). PATIENTS AND METHODS: The subjects were 15 patients who had been diagnosed with nonreducing disc displacement of the TMJ but had received no treatment. Chewing movement and masticatory efficiency were examined at the initial visit and at a mean follow-up of 21.7 months, using mandibular kinesiography and adenosine triphosphate ebteric-coated granules. As a control, 23 persons who had no current or previous TMJ symptoms were studied. RESULTS: The patients' clinical signs and symptoms tended to be alleviated during the follow-up period. In normal controls, chewing movement showed lateral excursion to the chewing side on both the right and left sides. In patients, chewing movement at the initial visit showed lateral excursion to the chewing side during chewing on the TMJ affected side, but no such deviation was noted during chewing on the TMJ unaffected side in the horizontal plane. However, chewing movement at follow-up became similar to that of controls. In patients, masticatory efficiency became better during the natural course, although that at follow-up did not always reach the control's level. CONCLUSION: In untreated patients with nonreducing disc displacement of the TMJ, chewing movement and masticatory efficiency tend to improve spontaneously.  相似文献   
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BACKGROUND: Although it is clear that dissemination via the blood system involves angiogenesis, it is uncertain whether tumors also induce lymphangiogenesis or simply invade existing peritumoral vessels. The purpose of this study was to elucidate changes in tumor blood and lymph vessels in cases involving the invasion of squamous cell carcinoma in the oral cavity, and its significance. Blood and lymph vessels densities in tongue carcinomas induced in hamsters were investigated. METHODS: Tongue cancer was induced by abrading the right margin of the tongue of each hamster with an endodontic barbed broach and subsequently applying 1.0% 9,10-dimenthl-1,2-benzanthracene (DMBA) dissolved in acetone, three times a week, at the same site. Fresh frozen sections were prepared and blood vessels stained blue by perfusion with Coomassie Brilliant Blue and lymph vessels stained brown for 5'-nucleotidase. The effects on the blood vessels and lymph vessels were observed. RESULTS: The results showed that blood and lymph vessel densities were greater in the advanced carcinoma tissues than in normal tissue. These were compared in terms of the mode of cancer invasion. As tumor invasion progressed, the blood vessel density decreased but lymph vessel density tended to be higher in high-degree tumor invasion than in low-degree tumor invasion. The expression of vascular endothelial growth factor-C was seen more frequently as tumor invasion progressed. CONCLUSIONS: The present findings indicated that angiogenesis and lymphangiogenesis are affected by cancerous invasion.  相似文献   
7.
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   
8.
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   
9.
A case of recurrent medullary thyroid cancer (MTC) was evaluated with123I-MIBG,99mTc(V)-dimercaptosuccinic acid (DMSA), and201Tl scintigraphy. This patient had been operated on for MTC in the right thyroid. Recently a left neck mass was noticed, and was suspected of being a. recurrence of MTC based on increased plasma calcitonin (CT) and carcinoembryonic antigen (CEA). He was operated on for the neck mass which revealed MTC, and papillary thyroid cancer was incidentally found in the left thyroid, but the CT and CEA levels remained high, and remaining MTC tumor was suspected. But the location of the tumor was unknown. Although99mTc(V)-DMSA scintigraphy is generally believed to be superior in sensitivity to123I-MIBG scintigraphy, it did not demonstrate the tumor site but201Tl and123I-MIBG did. Furthermore,123I-MEBG scintigraphy has greater specificity for tumors which arise in the neural crest. Judging from the results of this case and cases reported in the literatures, both123I-MIBG and99mTc(V)-DMSA should be performed in the detection of recurrent MTC.  相似文献   
10.
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   
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