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31.
32.
Almost one tenth of more than 370 hepatectomies, mostly for tumors, involved resection of major parts of the caudate lobe, subsegment 1. Five of them were for tumors or hemangiomas here, compressing or invading the vena cava; two were for metastases of colorectal cancer located very close to the junctions of the right and middle hepatic veins with the vena cava. We would previously have deemed these tumors unresectable. In these patients the vein was banded above and below the liver, an internal shunt tube placed in preparation for shunting of blood, and the afferent liver blood flow controlled. Control of the vena cava by tightening of the bands was needed in two cases. Tumor-invaded parts of the vein wall were resected in two other cases, in whom the presence of the tube facilitated the resection but the bands did not have to be tightened. The procedure did not cause morbidity and we conclude that tumors close to the vena cava can often be resected without complex vascular exclusion techniques, even when they invade the vein. 相似文献
33.
E Ohshima H Takami H Sato S Mohri H Obase I Miki A Ishii S Shirakura A Karasawa K Kubo 《Journal of medicinal chemistry》1992,35(18):3402-3413
A series of 11-[2-(1-benzimidazolyl)ethylidene]-6,11-dihydrodibenz[b,e]oxep in-2- carboxylic acid derivatives and related compounds were synthesized and found to be potent TXA2/PGH2 receptor antagonists. Each compound synthesized was tested for its ability to displace [3H]U-46619 binding from guinea pig platelet TXA2/PGH2 receptors. Structure-activity relationship studies revealed that the following key elements were required for enhanced activities: (1) an (E)-2-(1-benzimidazolyl)ethylidene side chain in the 11-position of the dibenzoxepin ring system and (2) a carboxyl group in the 2-position of the dibenzoxepin ring system. The studies also indicated that the TXA2/PGH2 receptor binding affinities of this series of compounds in guinea pig platelet were poorly correlated with those in human platelet. Introduction of substituent(s) to the benzimidazole moiety was effective and sodium (E)-11-[2-(5,6-dimethyl-1-benzimidazolyl)ethylidene]- 6,11-dihydrodibenz[b,e]oxepin-2-carboxylate monohydrate (57) recorded the highest affinity for human platelet TXA2/PGH2 receptor with a K(i) value of 1.2 +/- 0.14 nM. It demonstrated potent inhibitory effects on U-46619-induced guinea pig platelet aggregation (in vitro and ex vivo) and human platelet aggregation (in vitro). Compound 57, now designated as KW-3635, is a novel, orally active, and specific TXA2/PGH2 receptor antagonist with neither TXA2/PGH2 receptor agonistic nor TXA2 synthase inhibitory effects. It is now under clinical evaluation. 相似文献
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36.
S Higano S Takahashi K Ishii K Matsumoto H Ikeda K Sakamoto 《AJNR. American journal of neuroradiology》1994,15(8):1435
PURPOSETo describe MR and CT features of germinoma originating in the basal ganglia and thalamus and to discuss the roles of each modality for its diagnosis.METHODSMR and CT studies of six cases of germinomas, five of which were histologically proved, were retrospectively reviewed. T1-weighted, T2-weighted, and contrast-enhanced T1-weighted conventional spin-echo images, and unenhanced and contrast-enhanced CT images were evaluated.RESULTSTypically, the tumor consisted of an irregular solid area with contrast enhancement and various-size cysts. Cystic components were found in five cases and calcification in four. Intratumoral hemorrhage was noted in one. Ipsilateral cerebral hemiatrophy and brain stem hemiatrophy were noted in three cases each. MR was superior to CT in evaluating precise tumor extension, cystic components, and intratumoral hemorrhage, although in one case, extension of the tumor was better defined on CT in its early stage. Calcification was difficult to identify by MR alone. The solid components of the tumors generally showed slightly high density on CT, which seemed to be characteristic compared with nonspecific intensity pattern on MR.CONCLUSIONThe combination of CT and MR findings allows early detection and appropriate diagnosis of the mass in the basal ganglia and/or thalamus. 相似文献
37.
A case of a 43-year-old man with coexistence of intracranial and spinal cavernous angiomas is presented. The patient had a 2-year history of severe back pain incurred by neck flexion, and he became aware of weakness of the right lower extremity and paresthesia of the left lower extremity. Neurological examinations at the time of the first admission demonstrated incomplete Brown-Séquard syndrome. Myelograph, myelo-CT and contrast enhanced CT showed an intramedullary mass at the Th3-Th5 level. The patient received laminectomy with total removal of the lesion. Pathological diagnosis was cavernous angioma. Six years later, the patient complained of subacute weakness and numbness of the left upper extremity. Head CT demonstrated a high density lesion of about 2cm in diameter in the right frontal lobe. MRI showed a mixed signal intensity lesion with a marked low-intensity rim in the same area. Total extirpation of the lesion was performed. Pathological diagnosis of the intracerebral lesion was also cavernous angioma. Intramedullary cavernous angioma is very rare. Furthermore, bifocal cavernous angiomas involving both the spinal cord and the brain are extremely rare, and, only 5 cases have been reported in the literature. To our knowledge, this is the first case diagnosed by surgical specimens of coexisting intramedullary and intracerebral lesions. 相似文献
38.
The effect of diazepam on inbred mutant E1 mice, which develop convulsive seizures after repeated sessions of being tossed up, was examined. Acute administration of diazepam (32 mg/kg, i.p.) completely inhibited the convulsions. At that time, the dopamine level was increased in the cortex and hippocampus, and the norepinephrine level in the cerebellum was decreased. 5-Hydroxytryptamine levels were not changed. As for amino acids, the glutamine level increased and the levels of GABA, glutamic acid, aspartic acid, alanine and other amino acids were not changed. 相似文献
39.
Seventeen specimens of orbital fatty tissue taken from cases of dysthyroid ophthalmopathy at the time of operation were observed by light and electron microscopy, and also by immunohistochemical staining. The pathological changes observed were infiltration of the chronic inflammatory cells, deposit of fibrin, sclerosis of vascular wall, occlusion of the vascular lumen, and accumulation of hydrophilic mucopolysaccharide. Immunoglobulin G was detected in fat cells and lymphocytes, and some of the infiltrating lymphocytes were determined to be T cells, by immunohistochemistry. These findings suggested that the pathology of the dysthyroid ophthalmopathy was closely related to the chronic inflammation induced by the immune reaction. The exophthalmos was considered to occur due to edema secondary to chronic inflammation and accumulation of the mucopolysaccharides. 相似文献
40.
Chien-Huang Lin Feng-Nien Ko Hisahi Ishii Tsutomu Ishikawa Ih-Sheng Chen Che-Ming Teng H.-P. Kuo 《Naunyn-Schmiedeberg's archives of pharmacology》1997,355(2):210-216
We investigated the effects of a novel platelet-activating factor (PAF) receptor antagonist, CIS-19 [cis-2-(3, 4-dimethoxyphenyl)-6-isopropoxy-7-methoxy-1-(N-methylformamido)-1,
2, 3, 4-tetrahydronaphthalene], on PAF-, histamine-, substance P- and antigen-induced bronchoconstriction and microvascular
leakage, as well as PAF- and antigen-induced bronchial hyperreactivity to methacholine in urethane-anesthetized guinea-pigs.
Administration of CIS-19 (0.5–5 mg/kg, i.v.) inhibited the increase in lung resistance induced by PAF (30 ng/kg, i.v.) in
a dose-dependent manner, but failed to inhibit the increase induced by histamine (30 μg/kg, i.v.) or substance P (6.5 μg/kg,
i.v.). CIS-19 (5 mg/kg, i.v.) did not inhibit the increase in lung resistance induced by ovalbumin (2 mg/kg, i.v.) in actively
sensitized guinea-pigs. PAF (30 ng/kg, i.v.)-induced microvascular leakage, measured by the extravasation of Evans blue dye,
was dose-dependently inhibited by CIS-19 (0.5–5 mg/kg, i.v.) in the trachea, main bronchi and intrapulmonary airways, but
it did not affect histamine (30 μg/kg, i.v.)- or substance P (6.5 μg/kg, i.v.)-induced microvascular leakage at all airway
levels. CIS-19 (2.5 and 5 mg/kg) did not affect ovalbumin (2 mg/kg, i.v.)-induced microvascular leakage in all airway levels
in actively sensitized guinea-pigs. CIS-19 (2.5 and 5 mg/kg, i.v.) significantly inhibited PAF-induced enhancement of the
bronchial response to methacholine, but had no effect on ovalbumin (0.05 mg/kg, i.v.)-induced bronchial hyperreactivity in
actively sensitized guinea-pigs. It is concluded that CIS-19 is a potent PAF receptor antagonist which inhibits PAF- but not
antigen-induced bronchoconstriction, microvascular leakage and bronchial hyperreactivity. These results suggest that PAF plays
little or no role in early airway responses following antigen challenge.
Received: 29 April 1996 / Accepted: 10 October 1996 相似文献