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71.
Adult T-cell leukemia/lymphoma (ATLL) is recognized as a disease etiologically associated with human T lymphotropic virus type-1 (HTLV-1) infection, but, neither viral replication nor specific virus antigen expression have been detected on ATLL cells distributed in organs, including skin. To examine the latent expression of HTLV-1 in the cutaneous lesions of ATLL patients, we cultured the lesional skin tissues in vitro and applied immunofluorescence staining with mouse monoclonal antibodies Lt-4, GIN-14, and F10, which react with p40tax, p19 and gp21, respectively. We recognized HTLV-1 specific antigens on clustered ATLL cells only in the deeper dermis of the skin after 24 hrs cultivation of the lesional skin tissue from an ATLL patient in RPMI-1640 medium supplemented with 20% fetal calf serum. In the electron microscope, we observed HTLV-1 like particles, 80-140 nm in diameter with envelope and core structures, in the same tissue specimen. These findings suggest that HTLV-1 gene products may be expressed in the skin lesions of ATLL patients and involved in the pathogenesis of skin eruptions in cutaneous type ATLLs. To our knowledge, this is the first report that envisages the potency of intracutaneous HTLV-1 expression in vivo.  相似文献   
72.
We defined large striatocapsular infarcts as subcortical softenings of more than 20 mm in diameter involving the territories of the lateral and medial groups of lenticulostriate arteries. The aim of this study of 56 patients was to compare the clinical features and risk factors of these infarcts with those of cortical and lacunar infarcts. On the whole, our data suggest that both the clinical features and risk factors of large striatocapsular infarcts are similar to those of cortical infarcts, but significantly different from those of lacunar infarcts. The clinical manifestations of large striatocapsular infarcts with a maximum diameter of less than 50 mm may sometimes resemble those of lacunar infarcts because neuropsychological disorders are less frequent; however, our study indicates that, even in these cases, cardioembolic sources and artery-to-arteiy embolism are significantly more frequent in large striatocapsular than in lacunar infarcts, thus suggesting a different pathogenesis.  相似文献   
73.
Calcific tendinitis is a common condition with characteristic clinical and radiological findings. Although we do not know which condition initiated the pathologic cascade, we present a rare case of calcific tendinitis of the long head of the biceps brachii at its origin, associated with a SLAP lesion. The calcium deposit was removed and the SLAP lesion was repaired with a suture anchor arthroscopically.  相似文献   
74.
良性淋巴上皮病、淋巴上皮癌、MALT淋巴瘤的关系   总被引:1,自引:0,他引:1  
良性淋巴上皮病(benign lymphoepithelial lesion)、淋巴上皮癌(lymphoepithelial carcinoma)、黏膜相关淋巴组织型结外边缘区B细胞淋巴瘤(MALT淋巴瘤)(extranodal marginal zone B-cell lymphoma of mucosa-associated lymphoid tissue,MALT lymphoma)是3种性质不同但又存在某些关联的病变,本文对3种病变的病因、组织病理学表现及三者之间的关系进行了介绍,并结合叶为民等论文中的一些内容进行了简要探讨。  相似文献   
75.
We report a case of Noonan syndrome associated with central giant cell granuloma. The patient was a 101/2-year-old boy with the chief complaint of proptosis of the right eye. He also had various malformations such as short stature, webbed neck, pectus excavatum, cubitus valgus, pulmonary valve stenosis and patent foramen ovale, a characteristic face appearance and cryptorchidism and so on. Chromosome analysis showed a 46, XY karyotype. A computed tomographic scan and magnetic resonance imaging showed a mass originated from the lateral wall of the right maxillary sinus. The patient underwent Caldwell-Luc operation. Histological examination of the mass showed the characteristics of central giant cell granuloma. This case report describes a patient with the features of the recently described Noonan-like/multiple giant cell lesion syndrome.  相似文献   
76.
食管癌高低发区人群食管粘膜组织病理学研究   总被引:1,自引:0,他引:1  
目的探讨食管癌高、低发区人群食管粘膜上皮组织学改变,为癌前病变防治提供依据。方法高(林州市)、低发区(范县、清丰县)分别取无症状居民食管活检229人和187人,均分为4组,25岁~34岁、35岁~44岁、45岁~54岁及≥55岁,常规石蜡HE制片,按标准诊断归类。结果高、低发区食管上皮萎缩、棘层肥厚、炎细胞浸润相应年龄组比较无显著差异,基底细胞增生高发区35岁~44岁、45岁~54岁组显著大于低发区相应组(P=0.0312,P=0.0273),非典型增生45岁~54岁、≥55岁组高发区显著大于低发区相应组(P=0.0196,P=0.0263)。高、低发区总体人群比较除棘层肥厚、炎细胞浸润无差异外,余各病变间均有极显著差异(P<0.01)。结论食管上皮萎缩、基底细胞增生应作为较狭义的癌前病变对待,食管上皮棘层肥厚、炎细胞浸润似与食管癌变无关。  相似文献   
77.
Interruption of atrial flutter and fibrillation by RF catheter ablation may be favored by large, elongated lesions. We administered RF current in unipolar and bipolar mode in porcine right atrium. Bipolar ablation was performed between the tip electrodes of two serially coupled catheters. With 4-mm tip electrodes in vitro, lesion length increased from a mean (SD) of 7.9 (1.2) mm at 3 mm-interelectrode distance (IED) to 13.3 (3.3) mm at 9-mm IED, but decreased at 12-mm IED due to nonconfluent lesions (P < 0.0001), With 4 mm distal electrodes and 8 mm IED, bipolar lesions were 65% longer than corresponding unipolar ablations. Switching to bipolar mode increased the lesion length more than increasing electrode tip length to 6 mm in unipolar mode. Power and temperature controlled ablation created equally sized lesions. Twelve anesthetized pigs were randomized to unipolar or two catheter bipolar temperature controlled ablation of the right atrial free wall. Bipolar ablation created confluent lesions with endocardial length × width of 13.5 (5.8) × 7.3 (3.7) mm, unipolar ablation 6.4 (2.8) × 4.6 (1.4) mm (P < 0.001 when comparing length and P = 0.013 for lesion width). The atrial lesions in both groups were transmural and extended into hilar lung lesions with maximal depth of 3.0 (1.1) and 2.6 (1.0) mm, respectively (P = 0.44). Five bipolarly and four unipolarly ablated pigs developed right diaphragmal paresis. We conclude that bipolar ablation may be preferable in situations where large, elongated lesions are favorable. The two catheter technique is feasible in porcine right atrium. Both bipolar and unipolar ablation of the porcine right atrial free wall may frequently be complicated by injury to the phrenic nerve and adjacent lung tissue.  相似文献   
78.
Sensitization of striatal N-methyl- -aspartate receptors (NMDAR) has been linked to events leading to the motor response changes associated with the administration of dopaminomimetics to parkinsonian animals and patients. To determine whether tyrosine phosphorylation of NMDAR subunits contributes to the apparent long-term enhancement in synaptic efficacy of these receptors, we examined the effect of unilateral nigrostriatal dopamine system ablation with 6-hydroxydopamine followed by twice-daily treatment with -DOPA on the phosphorylation state of rat striatal NR2A and NR2B subunits. Three weeks of intermittent -DOPA administration produced a shortening in the duration of the rotational response to dopaminergic challenge and other changes mimicking those occurring in patients with Parkinson's disease. Concurrently, tyrosine phosphorylation of NR2A and especially of NR2B subunits increased ipsilateral to the lesion (20±5% and 46±7% of intact striatum, respectively; p<0.01) without attendant changes in subunit protein levels. Selective blockade of NR2B subunits with ACEA 10-1244, but not of NR2A subunits with MDL 100,453, reversed the -DOPA-induced response alterations. The intrastriatal injection of a tyrosine kinase inhibitor, genistein, at a dose (2.0 μg) that normalized the response shortening, attenuated the NR2A and NR2B phosphorylation increase by about 12% and 24%, respectively (p<0.01). Taken together, these results suggest that augmented tyrosine phosphorylation of NR2B subunits, alone or in combination with the smaller rise in NR2A subunit phosphorylation, contributes to the apparent enhancement in striatal NMDAR sensitivity and thus to the plastic alterations in dopaminergic responses in -DOPA-treated parkinsonian rats.  相似文献   
79.
目的:探讨P16、CyclinD1的表达在胃癌发生发展中的作用。方法:采用免疫组化S-P法。结果:在胃粘膜癌变过程中,P16阳性表达率逐渐下降,其中异型增生和胃癌组P16阳性表达率明显低于慢性浅表性胃炎组(P <0.05);CyclinD1阳性表达率逐渐增高,其中肠化生、异型增生和胃癌组CyclinD1阳性表达率明显高于慢性浅表性胃炎组(P <0.05)。在胃癌中,P16阳性表达率与胃癌分期和分化程度有关,CyclinD1的阳性表达率与之无关。结论:P16表达缺失和CyclinD1异常表达是胃癌发生过程中一个较早的分子事件,且P16表达缺失与胃癌进展和恶性程度有关。  相似文献   
80.
Cyst-like lesions in the radius and tibia were observed in two children as a post-fracture event. The pathogenesis of these lesions is discussed. Cut sections from anatomic specimens display extensive hemorrhage in subperiosteal as well as endosteal and trabecular bone. Cysts arising from hemorrhagic resorption in various locales may explain the occasional atypical appearance of these lesions.  相似文献   
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