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91.
A rare case of primary linitis plastica carcinoma of the colon seen in a 44 year old Japanese man is described herein. The patient had a complete obstruction of the descending colon and was treated with a loop colostomy followed shortly afterward by a left hemicolectomy. At the time of the second operation, the entire thickness of the colonic wall was found to be infiltrated by cancer cells, however, the other intraabdominal organs were free of cancerous involvement. The histopathological diagnosis made at this time was primary linitis plastica carcinoma of the descending colon. Nine months later, the patient developed an intestinal obstruction and relaparotomy revealed diffuse peritoneal dissemination. Two years after the first operation, upper GI films and a gastrofiberscopic examination revealed gastric involvement. The patient died 28 months after his initial operation, and autopsy revealed widespread metastases in the peritoneal surface, paraaortic lymph nodes, small intestine, remaining colon and stomach.  相似文献   
92.
The inhibitory effects of glycoproteins separated from a hot water extract of corn silk (U-CSE) on the formation of IgE antibodies after primarily and secondarily challenged responses with dinitrophenyl (DNP)-ovalbumin (OVA) antigen in mice were investigated using the passive cutaneous anaphylaxis (PCA) test. When U-CSE was given intranasally or intraperitoneally the day before primary immunization, IgE antibody production was strongly inhibited. Furthermore, it was found that new formation of IgE antibodies was readily inhibited by U-CSE administration in mice with high levels of IgE after primary immunization. It was also found that U-CSE markedly suppressed IgE antibody formation in secondarily challenged responses with the antigen. U-CSE may be clinically applicable to type I allergic diseases.  相似文献   
93.
The role of endoscopic retrograde cholangiopancreatography (ERCP) in the preoperative assessment of anomalous pancreaticobiliary junction was retrospectively evaluated in 74 consecutive patients (19 males and 55 females; aged 0–80 years). Sixty-three patients had congenital biliary dilatation and 11 did not. Type classification of congenital biliary dilatation was possible by ERCP alone in 45 patients (71%). The main causes of classification failure were previous bilio-enteric anastomosis and restriction of postural changes during ERCP due to general anesthesia in pediatric patients. Classification of anomalous junction was possible in 69 patients (93%). Technical difficulty in ERCP caused classification failure in 5 patients. Neoplastic lesions were found in 12 patients (16%) and all but 1 were correctly diagnosed by ERCP. We conclude that ERCP plays an important role in the preoperative diagnosis and type classification of anomalous pancreaticobiliary junction and congenital biliary dilatation.  相似文献   
94.
Phototransduction mechanisms have been so far investigated mostly in rods, whereas those in cones are much less known. In the present experiment, we investigated phototransduction mechanisms in inside-out patches excised from cone outer segments of the carp. Cyclic GMP-activated channels on the patch became light-sensitive when both GTP and Mg2+ were supplied by perfusion. When the channels were activated by a hydrolysis-resistant analogue of cGMP, activities were not suppressed by light even though both GTP and Mg2+ were present. Thus activation of transducin and phosphodiesterase (PDE) were involved in the transduction processes, indicating that phototransduction mechanisms in cones are qualitatively similar to those in rods. In cone patches, however, light responses fully terminated even though ATP was absent, opposing to the report that ATP was indispensable for light response termination in rods. The response termination in the cone patch might result from activation of guanylate cyclase and/or inactivation of PDE. Under the perfusion of GTP together with Mg2+ and 3-isobutyl-1-methyl xanthine, no channel activities were observed, indicating that no guanylate cyclase activity was present in cone patch preparations. Therefore, termination of the light response in the patch might be caused by inactivation of PDE which resulted from inactivation of photopigment and transducin. Based on these observations, differences in light response kinetics between the rod and cone are discussed.  相似文献   
95.
A case of non-Hodgkin's lymphoma showed a phenotypic and genotypic cell lineage switch twice during nine years of his clinical history; first, T-cell type, pleomorphic small cell lymphoma developed, followed by B-cell type, diffuse centroblastic/centrocytic lymphoma, and finally T-zone lymphoma without follicles again developed, from which AST-1 cultured cell line was established. Karyotype analysis demonstrated a shared abnormal chromosome, der(1)t(1;?)(p36;?), among the first relapsed B-cell tumor, the second relapsed T-cell tumor and AST-1 cell line. Furthermore, T-cell receptor (TCR) γ gene rearrangement bands of the same size were observed in the first relapsed B-cell tumor and the second relapsed T-cell tumor as well as AST-1 cell line. These results suggested that both relapsed tumors of different cell lineages are derived from a common malignant clone, presumably a committed lymphoid stem cell. A unique translocation, t(2;14)(q37;q11.2), which may involve TCR δ/α gene complex, was observed in the second relapsed tumor and AST-1 cells. To attempt to isolate the breakpoint of this translocation, the configuration of TCR δ/α gene complex was studied. The result showed that two rearrangements of TCR α gene detected with Jα probes were the products of the normal TCR rearrangement process, and were not involved in the translocation at this region. This patient, together with the AST-1 cell line, provided us a unique opportunity to study the development and clonal evolution of malignant lymphoma.  相似文献   
96.
We report 4 cases of myasthenia gravis in which myasthenic symptoms developed after a thymoma was known to be present. They include 3 invasive thymomas and one thymoma. In 3 of them, myasthenic symptoms developed 2–7 months after removal of the thymoma; in 1 case, myasthenic symptoms developed 11 years after the thymoma was known to be present. We also discuss here the possible pathogenetic mechanism of post-thymomectomic myasthenia gravis, and propose that it is due to the natural course of the disease.  相似文献   
97.
Pulmonary aspergillosis associated with old tuberculosis is generally resistant to treatment. Thus, if patients are treated only with conservative therapy, their condition continues to deteriorate due to repetitive hemoptysis, and may even become critical. Surgical treatment is required for these patients; however, it is extremely difficult to resect the lesion due to severe adhesions to the chest wall and vascular proliferation surrounding the lesion. We performed preoperative arterial embolization, achieving good results in three patients with hemoptysis caused by pulmonary aspergillosis. The feeding arteries were embolized using microcoils and/or gelatin sponges, and a lobectomy was safely carried out in all patients. We concluded that preoperative arterial embolization is a safe and effective technique to prevent massive hemorrhage occurring at the time of surgery. This work was presented at the 11th Annual Meeting of the Japanese Association for Chest Surgery, held in Kyoto, Japan, May 13–14, 1994  相似文献   
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100.
To clarify the physiological role of the mechanism that adrenergic nerve inhibits Ach release from intramural cholinergic nerve endings, the influence of Midaglizole, alpha 2-adrenergic receptor antagonist, to postprandial gastrointestinal motilities in conscious dogs was investigated. Postprandial motilities of gastric antrum, duodenum, ileum, and colon were significantly enhanced by Midaglizole (3.0-5.0 mg/kg body weight, i.v.). These excitatory responses were abolished by atropine (0.05-0.1 mg/kg body weight, i.v.). On the other hand, in most cases (29 cases out of 32), when Midaglizole was administered during quiesent phase of IMC, no change occurred in gastrointestinal motility. However, after subliminal dose of pentagastrin or cisapride, which stimulated Ach release from intramural cholinergic neuron without development of motility, was administered, Midaglizole induced phasic, postprandial motility-like contraction in gastrointestinal tract. Even in the fasted state, when Midaglizole was administered intragastrically, irregular contractions with high amplitude occurred in every regions from gastric antrum to colon. And these excitatory responses were abolished by atropine. Similar reaction was observed also in truncal vagotomized dogs. These results suggest that it is the physiological mechanism that adrenergic nerve presynaptically inhibits Ach release from intramural cholinergic neuron, which is the main mechanism of development of postprandial motility, acting on alpha 2-adrenergic receptor, and has tonic control of postprandial motility.  相似文献   
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