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1.
Summary: John Hughlings Jackson's theory of consciousness has been reconsidered. The author stressed that his uniqueness as a neuroscientist lay in his keen interest in the recursive nature of human consciousness. Two clinical symptoms of interest to Jackson were discussed: recurrent utterances and mental diplopia. Recurrent utterances were believed to represent an exceptional state, in which the unconscious process in speech production, otherwise destined to be swept away automatically, became manifest and observable. Jackson regarded mental diplopia as a revelation of otherwise inaccessible duality of all healthy mental actions. Therefore, he supposed that the essence of recursive consciousness resided in a transformation of multiple, multidirectional, unconscious processes into a linear, unidirectional process  相似文献   
2.
Effects of suramin, a polysulfonated naphthylurea compound, on metastatic ability, proliferation, and production of plasminogen activators and plasminogen activator inhibitors were studied using the highly metastatic human renal cell carcinoma cell line, SN12C-PM6. After renal subscapular implantation of tumor cells in nude mice, suramin significantly inhibited metastasis of tumor cells to the lungs and liver. In vitro growth of tumour cells was inhibited by suramin in a dose-dependent manner, at relatively low doses (ID50 = 105 µg/ml). Plasminogen activator inhibitor type 2 (PAI-2) production by tumor cells was enhanced by suramin (100 µg/ml), whereas urokinase-type plasminogen activator (uPA) production was suppressed. Thus, the increase in PAI-2 and the decrease in uPA production correlated with the inhibitory effects on tumour growth and metastasis by suramin. Therefore suramin may be beneficial for the treatment of patients with an early stage of renal cancer with potential risk of metastasis.  相似文献   
3.
A case of polymorphous low-grade adenocarcinoma (PLGA) in the submandibular gland is reported. A 72 year old woman presented with a 5 year history of a gradually expanding tumor in the submandibular region. The surgical specimen revealed a relatively well demarcated tumor, 35 × 35 × 20 mm in size. Macroscopically, necrosis and hemorrhage were not seen in the solid tumor. Histologically, the tumor growth pattern was variable, composed of tubular, papillary, solid, trabecular and cribriform structures. Immunohistochemically, some tumor cells were positive for epithelial membrane antigen (EMA), S-100 protein, keratin, and carcino-embryonic antigen (CEA). Electron microscopically, prominent microvilli projected into the luminal spaces, and basal lamina and hemidesmosomes were seen in the tumor cells adjacent to the connective tissues. The submandibular gland is an extremely rare location for PLGA. To the authors' knowledge, this is the first case of its kind reported in the English literature.  相似文献   
4.
To evaluate the potential of Atelocollagen gel as a carrier for chondrocyte transplantation, histological and biochemical characteristics of the chondrocytes in gel culture were compared with those in conventional monolayer cultures. Articular chondrocytes from 20 patients were isolated by enzyme digestion, embedded in Atelocollagen gel, and cultured for up to 4 weeks. The effects on proliferation, morphological changes, and synthesis of proteoglycans were analyzed by cell counts, light and electron microscopy, and measurement of isomers of chondroitin sulfates. Chondrocytes embedded in the Atelocollagen gel gradually proliferated and produced chondroitin 6-sulfate, maintaining the chondrocyte phenotype for up to 4 weeks. In contrast, although monolayer chondrocytes increased in number, most could be characterized as being fibroblast-like cells with a reduced capability of producing chondroitin 6-sulfate. The results suggest that Atelocollagen gel permitted a gradual proliferation and matrix synthesis of chondrocytes and maintaining its phenotype. Atelocollagen gel represents an important carrier for the clinical application of cultured chondrocyte transplantation for repair of cartilage defects.  相似文献   
5.
6.
Studies on the structure of the human chromosome were reviewed from the histological perspective and discussed in connection with our recent findings obtained mainly by atomic force microscopy (AFM). In this paper, we introduce several hitherto known models of the high-order structure of the metaphase chromosome and discuss the actual structure of chromosomes in relation to such structures as spiral chromatids, chromosome bands, and chromosome scaffolds. In chromosomes treated with Ohnuki's hypotonic solution, the chromosome arms were elongated and showed a characteristic spiral pattern of chromatid fibers. On the other hand, alternating transverse ridges and grooves were clearly observed on the surface of chromosomes treated with 0.025% trypsin for G-banding, and these ridges and grooves corresponded to the dark and pale bands of G-banded chromosomes. Similar findings were also found in chromosomes treated with quinacrine mastards for Q-banding. Fibers bridging the gap between the sister chromatids were often observed in G/Q-banded chromosomes; these fibers tended to be restricted within the G/Q-positive portions, suggesting the presence of chromatin fibers bridging these regions. Based on these findings in conjunction with previous studies, we outlined the high-order structure of the human chromosome. Recent advances in nanotechnology have provided new AFM techniques for the imaging and handling of materials at nano-scale resolution. Application of these techniques to chromosome research is expected to provide valuable information on the chromosome structure in relation to its function.  相似文献   
7.
Guidelines for treatment of ulcerative colitis in children   总被引:2,自引:0,他引:2  
This paper introduces the guidelines for treatment of ulcerative colitis in children, created by the working group of the Japanese Society for Pediatric Gastroenterology, Hepatology and Nutrition (Chair: Yuichiro Yamashiro) and the Japanese Society for Pediatric Inflammatory Bowel Disease (IBD) (Chair: Akio Kobayashi). The ideas of the working group, with regard to the fundamental differences in medical treatment between children and adults, included: (1) for children, intensive medical treatment including appropriate systemic management is important during the acute phase of illness. (2) Treatment with steroids, which can cause growth disturbances, should not be continued for long periods of time. (3) Pulsed steroid therapy, selective removal of blood cells, and intravenous infusion of cyclosporin should be included in the therapeutic option for severe and fluminant cases.  相似文献   
8.
We have reported that pretreatment by stomach tube with 8-methoxypsoralen (methoxsalen; 8-MOP), a potent human CYP2A6 inhibitor, strongly suppresses lung tumorigenesis by 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) in female A/J mice (Cancer Res. 2003). Here, we examined inhibitory effects with administration in the diet. When the mice were 7 weeks of age, they received dietary supplementation with 8-MOP at concentrations of 1, 10 or 100 ppm for 3 days prior to a single dose of NNK (2mg/0.1 ml saline/mouse, i.p.) or an equal volume of saline (vehicle control). The experiment was terminated 16 weeks after the first 8-MOP treatment and lung proliferative lesions were analyzed. The incidences and multiplicities in the 8-MOP 100 ppm-treated group were significantly reduced as compared with values for the NNK alone group (P<0.001). Multiplicities of NNK-induced lung proliferative lesions were also reduced in a dose dependent manner (Spearman rank correlation coefficient; rho=-0.806, correction P<0.0001). Mouse CYP2A4 and CYP2A5 differ from each other only 11 amino acids, and are closely related to the human CYP2A6. One hour after the last of three daily doses of 8-MOP (0.5, 5 or 50mg/kg body weight in 0.2 ml corn oil, given by stomach tube) or an equal volume of corn oil (vehicle control), given to the mice at 7 weeks of age, isolation of lung and liver RNAs demonstrated no effects on CYP2A4 and CYP2A5 mRNA levels with 8-MOP. In conclusion, the results of this study showed that clear dose response inhibitory effects of 8-MOP on NNK-induced lung tumorigenesis in female A/J mice fed diets containing 8-MOP, due to inhibition of enzyme activity of CYP2A4 and CYP2A5, rather than their gene expression.  相似文献   
9.
Secondary malignancies that develop after allogeneic-hematopoietic stem cell transplantation (allo-HSCT) have become serious issues. A 47-year-old man who developed acute myeloid leukemia in 2009 and subsequently underwent allo-HSCT twice: in 2009 and 2011. In 2015, voriconazole for lung aspergillus was started. In 2018, chronic graft-versus-host disease (GVHD) and multiple actinic keratoses manifested at his head. In 2020, some lesions were diagnosed as squamous cell carcinoma, so voriconazole was withdrawn, and subsequent surgery and radiation led to remission. Long-term administration of voriconazole in addition to allo-HSCT and chronic GVHD may be closely related to secondary skin cancer.  相似文献   
10.
We herein report a rare case of torsion of a wandering spleen in a patient with myeloproliferative disease. A 66-year-old Japanese woman presented to our hospital with abdominal pain and a fever. She had a medical history of polycythemia and secondary myelofibrosis. Abdominal enhanced computed tomography showed an enlarged spleen without enhancement in the lower pelvic region. The clinical diagnosis was severe torsion of a wandering spleen in a patient with myeloproliferative disease, necessitating surgical intervention. Splenectomy was performed after de-rotating to revascularize the spleen. After the operation, the platelet count gradually increased, and aspirin was administered to prevent thrombosis.  相似文献   
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