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The pulmonary lesions were studied in 24 autopsy cases of Japanese patients with AIDS. The major pathological findings were opportunistic infections, which were the major clinical symptoms in some patients. The pathogens identified were as follows; Pneumocystis carinii (PC) in 10, cytomegalovirus (CMV) in 14, atypical mycobacterium in 5, cryptococcus in 2, candida in 2, and nocardia in 1. PC pneumonia was prominent in 8 cases and was the cause of death. In such patients, the lung were heavy and appeared parenchymatous. Histological examination revealed numerous protozoa in the foamy material in the alveolar spaces, associated with swelling of the alveolar lining cells and edematous thickening of the alveolar septa. In some cases, only hyaline membrane formation was prominent without foamy material in the alveolar spaces. Immunostaining with anti-PC monoclonal antibody or in-situ hybridization with oligopeptide demonstrated pathogens in the hyaline membranes. Many cases with PC pneumonia had concomitant opportunistic infections such as CMV, Herpes simplex virus, and atypical mycobacterium. Extrapulmonary infection of PC was seen in only one case. CMV infection was found in 14 cases; 7 had innumerable inclusion bodies, and in some cases the lesions were most prominent around the bronchioles. Of the 5 cases of atypical mycobacterial infection, 2 were caused by M. kansaii (MK) and 3 by M. avium intracellulare (MAI). Both lesions of MK infection showed necrosis and cavitation. One of three cases of MAI infection showed cavitation. Around the cavitary lesions, numerous cytomegalic inclusion bodies were identified in the mesenchymal cells, which may have been the cause of necrosis and cavitation of the lesions. MAI infection was systemic and pronounced in the lymph nodes, spleen, and intestinal mucosa. Neoplastic lesions comprised 2 cases of Kaposi's sarcoma and 4 of extranodal non-Hodgkin lymphoma in other organs. Lung involvement was seen in only one case of Kaposi's sarcoma although very small in size. The lesion was situated along the pulmonary vein and appeared hemorrhagic macroscopically. Pulmonary lesions in AIDS are complicated, and many of opportunistic pathogens were identified in single patients.  相似文献   
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An analysis of subretinal fluid in bullous retinal detachment   总被引:1,自引:0,他引:1  
A patient with bilateral bullous retinal detachment underwent drainage of the subretinal fluid. The analysis of the subretinal fluid revealed a high protein concentration--17.4 g/dl OD, 27.5 g/dl OS--which was 3-5 times higher than that of the patient's serum. The protein fractionations of the subretinal fluid were almost the same as those of the serum. These findings may well explain the shifting fluid and support the theory that bullous retinal detachment is caused by the breakdown of retinal pigment epithelial function as a barrier between the choroid and retina.  相似文献   
5.
Staphylococcus intermedius isolates from dogs (n = 44) and pigeons (n = 62) were categorized into 12 types by intergenic ribosomal DNA spacer polymorphism analysis. All isolates from pigeons were lukS positive and all isolates from dogs were lukS and lukF positive by dot blot analysis. The mean leukotoxicity titer for dog isolates was at least 129-fold higher than that for pigeon isolates.  相似文献   
6.
CD5 expression in thymic carcinoma.   总被引:5,自引:0,他引:5       下载免费PDF全文
To determine the differences between the cellular characteristics of thymic carcinoma and thymoma, immunohistochemical analysis with lymphocyte markers (CD1a, 3, 4, 5, 8, 10, 20, 21, 25, 30, 57, and 72) was performed on 23 thymic epithelial tumors other than lymphocytic thymoma: overt thymic carcinoma (OC, n = 7), atypical thymoma (n = 5), and typical thymoma (epithelial or mixed thymoma, n = 11). Among the surface antigens examined, CD5, a type of receptor molecule that signals cell growth in T cells, was expressed in neoplastic epithelial cells of the thymus, in OC (seven of seven) and atypical thymoma (two of five), but not in typical thymoma. Double labeling immunofluorescence demonstrated expression of CD5 in cytokeratin-positive cells. The CD5 molecule extracted from an OC tumor showed the same molecular size as that in the spleen, but CD72, a ligand of CD5 on the surface of B cells, was not found in the epithelial cells of OC or atypical thymoma. Expression of CD5 was not observed in carcinomas of other organs, such as lung (n = 15), breast (n = 4), esophagus (n = 6), stomach (n = 6), colon (n = 9), and uterine cervix (n = 3). CD5 is closely related to morphological changes in thymic epithelial tumors and may play a role in the evolution of OC through receptor-ligand interaction.  相似文献   
7.
Fibrillary inclusions in neoplastic and fetal acinar cells of the pancreas   总被引:1,自引:0,他引:1  
We report a case of pancreatic acinar cell carcinoma which contained a large number of pleomorphic inclusions with fibrillary internal structures and mature zymogen granules. To clarify the significance of fibrillary inclusions in the differentiation of acinar cells of the pancreas, we further investigated fetal pancreases (gestational weeks 16, 17, 19, 20 and 28). We found two types of inclusions: type A, corresponding to fibrillary inclusion of neoplastic acinar cells, was observed only in a 19-week fetus; type B showed a homogeneous density similar to that of zymogen granules. Type B was observed in all the fetuses after the 17th gestational week. Although the type A inclusion might be generated throught a different mechanism than the type B inclusion, the appearance of a large number of fibrillary inclusions in neoplastic acinar cells may represent a transient form of zymogen granule.  相似文献   
8.
The neuropathologiesl features of the central nervous system in IS autopsy cases of Japanese male with AIDS were reported. Nine patients had various histological changes including a variety of opportunistic infections in six patients (40%), primary malignant lymphoma of the brain in two (13%), AIDS encephalopathy in four (27%) and vacuolar myelopathy in one (7%). Usually, these pathological changes were present concomitantly. AIDS encephalopathy was characterized by infiltration of mono and multinucleated cells and myelin pallor with astrogliosis located predominantly in the cerebral white matter and subcortical gray matter. Furthermore, unevenly distributed neuronal loss of the cerebral cortex was apparent in one case. Diffuse astrocytosis of the gray matter out of proportion to neuronal loss was also an outstanding finding in another case. The present study suggested that not only the white matter changes but also gray matter alterations might be the morphological substrates of AIDS encephalopathy.  相似文献   
9.
An unusual case of encephalomyeloneuritis associated with germ cell tumor with mature and immature teratoma arising in the mediastinum is presented. There was an unusually long interval from the onset of neurologic symptoms to the development of malignancy. The histopathology, characterized by limbic encephalitis, brain stem encephalitis, cortical cerebellar degeneration and myeloneuritis, was similar to that of paraneoplastic encephalomyeloneuritis previously described in the literature. Virological and immunological studies failed to demonstrate any causative agents or autoantibodies reacting with brain tissue. The causal relationship between the malignant neoplasm and encephalomyeloneuritis thus seems to be very complex.  相似文献   
10.
STUDY OBJECTIVES: There is a long-standing controversy surrounding the existence of dream experiences during non-rapid eye movement (NREM) sleep. Previous studies have not answered the question whether this "NREM dream" originates from the NREM sleep mechanism because the subject might simply be recalling experiences from the preceding rapid eye movement (REM) sleep. METHODS: We scheduled 11 healthy men to repeat 20-minute nap trials separated by 40-minute periods of enforced wakefulness across a period of 3 days. At the end of the nap trial, each participant answered questions regarding the formal aspects of his dream experiences during the nap trial, using the structured interviews. RESULTS: We obtained a total of 172 dream reports after naps containing REM sleep (REM naps) and 563 after naps consisting of only NREM sleep (NREM naps). Dream reports from NREM naps were less remarkable in quantity, vividness, and emotion than those from REM naps and were obtained more frequently during the morning hours when the occurrences of REM sleep were highest. CONCLUSIONS: These results suggest that the polysomnographic manifestations of REM sleep are not required for dream experiences but that the mechanisms driving REM sleep alter experiences during NREM sleep in the morning. A subcortical activation similar to REM sleep may occur in human NREM sleep during the morning when REM sleep is most likely to occur, resulting in dream experiences during NREM sleep.  相似文献   
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