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991.
Ten patients with isolated subcutaneous nodules histologically similar to rheumatoid nodules were studied. Because of the intense fibroblastic reaction in one such nodule, it was initially mistaken for a fibrosarcoma. The nodules tended to be multiple and recurrent, with eventual spontaneous regression, and they were not associated with any systemic illness. The etiology of these lesions is unclear but the possibility of subsequent development of systemic rheumatoid disease is remote.  相似文献   
992.
A case of systemic candidiasis (Candida albicans) in a 1 1/2 year old dog is reported. Clinically, the first manifestation was enlargement of a superficial inguinal lymph node. Later several peripheral lymph nodes were affected and a fistulous opening appeared, communicating with an inflammatory process in the right humerus. Necropsy revealed gross lesions in the kidneys, pancreas and multiple lymph nodes. In addition, microscopic lesions were observed in the myocardium and the bone marrow of the right humerus. The lesions, which contained large fungal colonies, were mainly granulomatous with numerous multinuclear giant and epitheloid cells, but necrosis and suppuration were also evident. The site of invasion is not known. However, a previous perianal and abdominal dermatitis, which was treated locally with antibiotics and corticoids, could possibly have been a mycotic infection.  相似文献   
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In some patients acute pulmonary emboli may fail to resolve normally, resulting in chronic pulmonary embolism. This may lead to pulmonary hypertension, respiratory insufficiency, cor pulmonale, and death. The angiographic evaluation in nine patients with chronic pulmonary embolism who underwent embolectomy is presented. Particular emphasis on the predictive value of selective bronchial arteriography in four of these patients is considered. In chronic pulmonary embolism, pulmonary arteries distal to obstructed areas may remain patent and be supplied by hypertrophied bronchial arteries. Since back-bleeding of arterial blood from the bronchial circulation at surgery may predict the success of embolectomy, preoperative bronchial arteriography may be useful for predicting potential surgical success.  相似文献   
996.
The role of the RAD57 gene in double-strand gap (DSG) repair has been examined. The repair of a linearized plasmid, bearing a DSG, has been analyzed in a rad57-1 mutant of Saccharomyces cerevisiae. For effective rejoining of the ends of plasmid DNA in the rad57 mutant the sequence of chromosomal DNA homologous to the DSG region is required. However, DSG repair (restoration of plasmid circularity) in rad57 cells is not accompanied by the recovery of DSGs. The DSG repair, which depends on an homologous chromosomal DNA sequence, requires the cohesive ends of DSGs. The non-cohesive-ended DSGs are repaired in rad57 cells by a pathway independent of the homologous recombination between chromosomal and plasmid DNA. We presume that the rad57-1 mutation is connected with the inhibition of DNA repair synthesis, required for filling the DSG. This situation produces a condition of "homology-dependent ligation", the alternative minor mechanism of recombinational DSG repair, that takes place in mutant cells. A molecular model for "homology-dependent ligation" in rad57 cells is proposed.  相似文献   
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The dynamics of the spontaneous electrical activity of the rostral, dorsal, ventral and caudal claustrum was studied chronically in 12 dogs with biologically significant distinctions in the physiological state of the animals: extinction of orientative reflexes, replacement of the feeding conditions for the acid and defensive situation and elaboration of internal inhibition. The obtained data correlated with the hypothesis on an intermediate position of the claustrum between the cortex and subcortex and permit expressing a suggestion on availability in this nucleus of special representations for different physiological activities, in particular--orientative, feeding, rejecting and defensive. The ventral claustrum seems to take a maximal part in the orientative behaviour, the rostral and caudal claustrum--in the feeding behaviour, and the dorsal and ventral parts of the nucleus--in the rejecting and the defensive behaviour.  相似文献   
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