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11.
Antibodies to 3-methoxy-4-aminoazobenzene (3-MeO-AAB) and 2-methoxy-4-aminoazobenzene (2-MeO-AAB) DNA adducts were raised in rabbits against in vitro-adducted DNA samples. The enzyme-linked immunosorbent assay (ELISA) was used to determine the sensitivity and specificity of these antibodies. They proved highly specific for the modified DNA used as the immunogen, but cross-reacted with each other. Moreover, they showed cross reactivity with DNA modified by 4-( o -tolylazo)- o -toluidine, but not by other carcinogens, such as 4-aminobiphenyl or 4-nitroquinoline 1-oxide. The 50% inhibition level of antibody binding in the competitive ELISA was at 10–20 fmol of modified base per assay (equivalent to 1–2 adducts per 106 bases). Immunohistochemical staining indicated that these antibodies bind specifically to nuclear components of the liver in rats given either 3-MeO-AAB or 2-MeO-AAB at the dose of 50 mg/kg body weight.  相似文献   
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13.
The procedure used for an anterior capsulotomy is extremely important for successful in-the-bag intraocular lens insertion. An incision line in the extreme periphery may obscure the margin of the residual anterior capsule and make it difficult to confirm the position of the implanted lens. I describe a U-shaped anterior capsulotomy that facilitates in-the-bag insertion, discuss the importance of the location of the positioning holes for proper rotation, and introduce a modified J-loop posterior lens with the positioning holes in an alternative position.  相似文献   
14.
The purpose of this study is to investigate the relation between the fine structure of the tumor cell surface and the tumor malignancy by scanning electron microscopy. Practically, comparison was made between the invasive Ehrlich ascites clone 1 tumor and the non-invasive Ehrlich ascites clone 3 tumor, and also between the 4th postinoculation day and the 6th postinoculation day as regards the growth of microvilli on the cell surface. On the 4th postinoculation day, an invasive clone 1 tumor cell was indistinguishable from a non-invasive clone tumor cell because of their common paucity of microvilli development. On the 6th postinoculation day, the former was associated with exuberant growth of microvilli, and was clearly distinguished from the latter in which the density of microvilli stayed low as before. The appearance of dense microvilli growth in the invasive clone 1 tumor cells chronologically coincided with the stage of fatal bleeding into the abdominal cavity. Hydrocortisone with a dose of 1 mg/mouse, when given subcutaneously to a tumor-bearing mouse on the 4th postinoculation day, stimulated the development of microvilli in both clone 1 and clone 3 tumors. The enhancing effect of the hormone on this process was detectable 2 hours after hormone injection. It was indicated that the dense growth of microvilli in the clone 1 tumor facilitated its tumor invasion into visceral organs, and that the enhancing effect of hydrocortisone on microvilli development was to be related to the promotion of malignant transformation. The possible implications of glucocorticoid in mammocarcinogenesis are discussed from the point of view of comparative endocrinology.  相似文献   
15.
MR appearance of parasymphyseal insufficiency fractures of the os pubis   总被引:1,自引:0,他引:1  
Objective. To clarify the MRI features of parasymphyseal insufficiency fractures of the os pubis. Design and patients. MRI was performed in four postmenopausal women with parasymphyseal insufficiency fractures. The diagnosis was confirmed with plain films in every patient. T1-weighted and T2-weighted images were obtained in four patients using a 1.5-T unit. Postcontrast T1-weighted imaging was also done in three patients. Results and conclusions. MRI of pubic parasymphyseal insufficiency fracture characteristically demonstrates a hyperintense mass lesion with a hypointense rim on T2-weighted imaging, showing peripheral and septal enhancement after contrast administration. It is important to have this entity in mind in patients with osteoporosis, especially in patients with a history of pelvic irradiation for malignant disease, so as not to misinterpret it as a chondroid tumor or bone metastasis.  相似文献   
16.
A rare case of a 25-year-old man with pulmonary aspergillosis is reported. Pulmonary bulla and eosinophilic pneumonia in the right upper lobe were diagnosed by chest roentgenogram and transbronchial lung biopsy. Because the patient developed infective bullae during steroid therapy, we performed transcutaneous thoracic drainage and right upper lobectomy. The resected lung tissue contained numerous hyphae of Aspergillus. Around the hyphae of Aspergillus, granulomatous reaction and eosinophilic infiltration were observed. Antibodies against Aspergillus were detected in the serum of the patient. The number of peripheral blood eosinophils decreased after right upper lobectomy. These findings suggest that pulmonary bullae and eosinophilic pneumonia may be a rare manifestation of pulmonary aspergillosis.  相似文献   
17.
We evaluated the bronchial hyperresponsiveness to methacholine in the two cases of eosinophilic pneumonia with infiltration of eosinophils into bronchial mucosa. Bronchial responsiveness was not increased in either case in spite of marked infiltration of eosinophils into the bronchial mucosa and submucosa. Hypodense eosinophils are reported in the sputum of patients with bronchial asthma. This suggests that infiltration of activated eosinophils into the bronchial mucosa is an essential factor in bronchial hyperresponsiveness.  相似文献   
18.
Recent studies have revealed that the phosphatidylinositol 3-kinase (PI3-K) pathway is involved in apoptotic cell death after experimental cerebral ischemia. The serine-threonine kinase, Akt, functions in the PI3-K pathway and prevents apoptosis by phosphorylation at Ser473 after a variety of cell death stimuli. After phosphorylation, activated Akt inactivates other apoptogenic factors, including glycogen synthase kinase-3beta (GSK3beta), thereby inhibiting cell death. However, the role of Akt/GSK3beta signaling in the delayed death of hippocampal neurons in the CA1 subregion after transient global cerebral ischemia (tGCI) has not been clarified. Transient global cerebral ischemia for 5 mins was induced by bilateral common carotid artery occlusion combined with hypotension. Western blot analysis showed a significant increase in phospho-Akt (Ser473) and phospho-GSK3beta (Ser9) in the hippocampal CA1 subregion after tGCI. Immunohistochemistry showed that expression of phospho-Akt (Ser473) and phospho-GSK3beta (Ser9) was markedly increased in the vulnerable CA1 subregion, but not in the ischemic-tolerant CA3 subregion. Double staining with phospho-GSK3beta (Ser9) and terminal deoxynucleotidyl transferase-mediated uridine 5'-triphosphate-biotin nick end labeling showed different cellular distributions in the CA1 subregion 3 days after tGCI. Phosphorylation of Akt and GSK3beta was prevented by LY294002, a PI3-K inhibitor, which facilitated subsequent DNA fragmentation 3 days after tGCI. Moreover, transgenic rats that overexpress copper/zinc-superoxide dismutase, which is known to be neuroprotective against delayed hippocampal CA1 injury after tGCI, had enhanced and persistent phosphorylation of both Akt and GSK3beta after tGCI. These findings suggest that activation of the Akt/GSK3beta signaling pathway may mediate survival of vulnerable hippocampal CA1 neurons after tGCI.  相似文献   
19.
A 48-year-old man presented with malignant hypertension and massive proteinuria. Renal angiography showed complete obstruction of the left renal artery and 99mTc-mercaptoacetylglycine (MAG3) renography showed a nonfunctioning left kidney. Percutaneous transluminal renal angioplasty of the left renal artery was unsuccessful; hence, the patient underwent left nephrectomy because of uncontrolled hypertension and proteinuria. Histological examination of a right kidney specimen revealed lesions of focal segmental glomerulosclerosis with benign nephrosclerosis. In contrast, histology of the left kidney showed typical ischemic kidney with hypertrophy of arteriolar smooth muscle cells. The patient responded favorably to the nephrectomy, as his blood pressure and urinary protein dramatically decreased with no antihypertensive medication. This case illustrates the heterogeneous effect of the renin-angiotensin system on either kidney in patients with renovascular hypertension due to unilateral renal artery stenosis.  相似文献   
20.
Among 43 men more than 60 years old who complained of urinary irritative symptoms 40 had subclinical lesions in the brain on magnetic resonance imaging (MRI). Of these 40 patients 23 (57.5%) had detrusor hyperreflexia. The mean age of the patients with and without detrusor hyperreflexia was 75.8 and 68.2 years, respectively, which is a statistically significant difference. Patients with detrusor hyperreflexia were more likely to have lesions of the basal ganglia than patients without detrusor hyperreflexia. This study suggests that detrusor hyperreflexia, subclinical MRI lesions in the brain and aging are intimately interrelated.  相似文献   
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