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1.
Cancer Chemotherapy and Pharmacology - Cancers are methionine (MET) and methylation addicted, causing them to be highly sensitive to MET restriction. The present study determined the efficacy of...  相似文献   
2.
A 22-year-old man was urgently admitted for pneumothorax. He continued complaining of exertional dyspnea and dry cough after the pneumothorax healed. About three months later, an atypical pulmonary mycobacteriosis by mycobacterium kansasii was identified. Exertional dyspnea increased after chemotherapy was administered, and the patient was readmitted because of difficulty in daily life activities. Chest radiographs and CT scans showed bilateral pulmonary hyperinflation and a narrowed heart shadow. There was also marked combined ventilatory impairment, as identified by a respiratory function test. Furthermore, the histological findings of surgically removed lung tissue revealed accumulation of lymphocytes in the wall of a small bronchus. Idiopathic bronchiolitis obliterans was diagnosed from the clinical course and clinical findings. The patient is now being monitored and is awaiting lung transplantation.  相似文献   
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We have investigated the effects of short-contact topical application of tretinoin using 16 male db/db mice by creating two full-thickness wounds on the skin of the back. A 0.1% tretinoin aqueous gel was applied to one wound for five minutes daily for five successive days while only aqueous gel was applied to the other (control). The mean (SD) percentage surface area unhealed before and after treatment were 0.88 (0.3) and 0.64 (0.15). In tretinoin-treated mice and non-treated mice (controls), the mean (SD) thicknesses of granulation were 1.383 (697) micro m and 683 (413) micro m, the density of capillary vessels in granulation was 12.2 (5.5)% and 5.7 (3.9)%, respectively. Differences between the two groups were significant for each variable. Wound healing was accelerated with short-contact topical application of tretinoin in db/db mice.  相似文献   
5.
Primary aqueductal stenosis is one of the main causes of congenital hydrocephalus in humans and experimental models. The congenitally hydrocephalic rat strain LEW/Jms is one such model. In this report, we describe further detailed histological features of periaqueductal structure, including the posterior commissure, subcommissural organ (SCO), and ependyma, and discuss the changes in these structures in relation to the cause of hydrocephalus. Coronal sections of the aqueduct in normal rats showed that the usual ependyma was absent in the center of the base facing the dorsal side, which was replaced by tall columnar cells. On the other hand, in hydrocephalic rats the ependyma encircled the aqueductal cavity. In midline sagittal sections, normal and hydrocephalic rats showed the SCO, although the SCO in hydrocephalic rats was shorter than in normal rats. There was also a marked difference between normal and hydrocephalic rats in the dorsoventral dimension of the rostral midbrain. In hydrocephalus, this dimension was large in comparison with normal rats. The superior collicular commissure located caudal to the posterior commissure ran along the ventral side of the midbrain in rats with hydrocephalus, and there was a cell-depleted area just dorsal to the superior collicular commissure. The same findings were observed from the 17th day of gestation until the postnatal period. Although the role of the SCO has been widely discussed from the viewpoint of secretory function, the present study indicated that this organ might be involved in the formation of the shape of the aqueduct.  相似文献   
6.
Magnetic resonance imaging (MRI) has greatly facilitated morphologic evaluation of spinal cord lesions. Eleven cases representative of inflammatory, demyelinating, neoplastic and vascular diseases, are presented which illustrate and summarize important abnormal features in spinal cord imaging, particularly MR findings. Recently, specialised techniques such as MR angiography, fat-inhibiting methods, dynamic MRI and functional imaging have been developed. These methods have facilitated not only lesion diagnosis but also qualitative assessment, and are being used to analyze pathophysiology. Comprehensive diagnoses based on such modalities may be important in determining indications for surgery or defining the extent of surgery or the intensity of other treatments.  相似文献   
7.
A successful replacement of the aorta from the ascending aorta to the supraceliac abdominal aorta in one operation is herein reported. The patient was 66-year-old woman who had DeBakey type I chronic aortic dissection with a pre-disseminated intravascular coagulation (DIC) condition. The image diagnosis revealed a markedly enlarged false lumen with a narrow true lumen in the ascending aorta extending to the diaphragm level while below the diaphragm level, the aortic dilatation was mild. The operation was performed through both a thoracoabdominal incision and a median sternotomy to expose the whole thoracic aorta, and the aorta was replaced from the ascending aorta to the supraceliac abdominal aorta. Selective cerebral perfusion was used for cerebral protection and this was a useful adjunct since no time limitations were thus required during repair of the aortic arch. Although the patient developed several complications postoperatively, she eventually recovered and was discharged from the hospital without any neurological disorders.  相似文献   
8.
The aim of this study was to examine if adhesion molecules had relation with degeneration and regeneration processes of mammalian vestibular epithelia. The distribution of E-cadherin and beta-catenin was immunohistochemically examined in normal and aminoglycoside-treated utricles of mice. E-cadherin and beta-catenin linearly expressed between epithelial cells in normal specimens. Aminoglycoside injury resulted in temporal alteration in distribution of these molecules with induction of apoptosis in hair cells. Degradation of both molecules was widely observed in vestibular epithelia, while some supporting cells exhibited accumulation of beta-catenin. After completion of induction of apoptosis, expression of these adhesion molecules was normal in distribution. These findings suggest that the E-cadherin-beta-catenin complex plays roles in degeneration and subsequent repair processes in vestibular epithelia affected by aminoglycosides.  相似文献   
9.
We defined mixed-dust pneumoconiosis (MDP) pathologically as a pneumoconiosis showing dust macules or mixed-dust fibrotic nodules (MDF), with or without silicotic nodules (SN), in an individual with a history of exposure to mixed dust. We defined the latter arbitrarily as a mixture of crystalline silica and nonfibrous silicates. According to our definition of MDP, therefore, MDF should outnumber SN in the lung to make a pathologic diagnosis of MDP. In the absence of confirmation of exposure, mineralogic analyses can be used to support the pathologic diagnosis. The clinical diagnosis of MDP requires the exclusion of other well-defined pneumoconioses, including asbestosis, coal workers’ pneumoconiosis, silicosis, hematite miners’ pneumoconiosis, welders’ pneumoconiosis, berylliosis, hard metal disease, silicate pneumoconiosis, diatomaceous earth pneumoconiosis, carborundum pneumoconiosis, and corundum pneumoconiosis. Typical occupations associated with the diagnosis of MDP include metal miners, quarry workers, foundry workers, pottery and ceramics workers, and stonemasons. Irregular opacities are the major radiographic findings in MDP (ILO 1980), in contrast to silicosis, in which small rounded opacities predominate. Clinical symptoms of MDP are nonspecific. MDP must be distinguished from a variety of nonoccupational interstitial pulmonary disorders.  相似文献   
10.
Centromere protein F (CENP-F) expression (localization and characteristics) in relation to tumor clinicopathological parameters was immunohistochemically examined and evaluated in 47 archival biopsy specimens of buccal and gingival squamous cell carcinomas (SCC). Centromere protein F expression was detected in 79% of the samples. An increase in the labeling index (LI) with WHO grading was obtained ( P  < 0.05). Correlations were obtained between the CENP-F LI and tumor size ( P  < 0.05). Immunoelectron microscopy showed CENP-F nuclear staining as punctate or fine dots. The present study shows that CENP-F expression and detection of a more specific cell subpopulation presents a theoretical advantage for the analysis of the precise cell cycle of G2 to M cells, compared to Ki-67.  相似文献   
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