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71.
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
李江 《中国口腔颌面外科杂志》2007,5(5):379-380
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
72.
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
73.
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
74.
OLE-GUNNAR ANFINSEN ERIK KONGSGAARD ARNOLD FOERSTER HALFDAN AASS JAN P. AMLIE 《Pacing and clinical electrophysiology : PACE》1998,21(1):69-78
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
75.
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
76.
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
77.
目的通过对32例窒息后心肌受累的新生儿治疗前后心肌酶谱测定,了解心肌酶谱在窒息新生儿心肌损害诊治中的意义。方法32例均自入院后12h及治疗后5~7天各静脉采血1次,作GOT、LDH、CK、CK-MB检查。结果窒息后心肌损害治疗前后心肌酶谱各项指标比较差异均有显著统计学意义(P〈0.01),出院时心肌酶多恢复正常。结论对窒息新生儿做心肌酶谱检查,有利于早期发现心肌损害并及时治疗,并可作为判断疗效及预后的指标。 相似文献
78.
During the early stages of nerve implantation, we followed the dynamic properties of the lateral gastrocnemius muscle of the rat, reinnervated with an acutely or chronically severed peroneal nerve. The aim of this study was to ascertain whether (1) the better functional recovery of a muscle reinnervated by a chronically severed foreign nerve is present from the onset of reinnervation, and (2) whether such functional improvement is due to the conditioning lesion effect. Our results indicate that better functional recovery is already apparent one week after nerve implantation, and it is due to the conditioning lesion effect, since tenotomy prevents such improvement. The tenotomy effect underlines the fact that some environmental factors concerning the target tissue, and not only the predegenerated nerve, are involved in the conditioning effect. © 1995 Wiley-Liss, Inc. 相似文献
79.
Although the esophagus is the most frequent site ofCandida infections in the gastrointestinal tract, and many clinical studies about it have been reported, little attention has been
directed toward experimental candidiasis of the esophagus, especially with regard to its ultrastructure. Using transmission
electron microscopy, this study was performed to clarify the ultrastructure of experimental lesions, obtained from five New
Zealand white male rabbits which were given a suspension ofCandida albicans cells (107/ml) for 13 days. The results showed that the lesions consisted of exfoliating, squamous epithelial cells with mycelial elements
ofCandida albicans cells penetrating through them, and that a widened intercellular space between individual cells in the area of candidial
invasion seems to be a characteristic finding of candidial infection.
A part of this study was presented at the 25th Annual Meeting of the Clinical Electron Microscopy Society of Japan, Matsumoto,
September 28–30, 1993. 相似文献
80.
Idiopathic scoliosis: biomechanics and biology 总被引:9,自引:0,他引:9
For whatever reason, right-left asymmetry has attracted an illogical proportion of research effort. Non-structural scoliosis, for example secondary to a leg length inequality, is indeed a problem of right-left asymmetry, but structural scoliosis is a complex three-dimensional deformity involving all planes. Biomechanical, biological and clinical evidence indicates clearly that the problem is one of front-back asymmetry and not right-left. The importanc of biological factors lies in their ability to bring the spinal column to and beyond its buckling threshold. Thus a taller and more slender spine is more liable to bend and, being stiffer in the sagittal plane, favours movement into other planes. This epitomises the spine of the scoliosis patient who is growing faster with a spinal template similar to other family members allowing idiopathic scoliosis to express itself genetically. It is the opposite condition to idiopathic hyperkyphosis (Scheuermann's disease), but this deformity is rotationally stable, thus remaining in the sagittal plane. The presence of an adjacent area of lordo-scoliosis below the region of hyperkyphosis testifies to the common nature of the pathogenesis of idiopathic scoliosis and Scheuermann's disease. It is the area of compensatory hyperlordosis below the Scheuermann's area that has obligatorily buckled and represents a human model supporting the lordosis theory, as does surgically tethering the back of the young growing human spine, which crankshafts accelerated progression. Similarly the only successful animal model of the formation of idopathic follows creation of a lordotic spinal segment in an otherwise kyphotic spine. For centuries, engineers have recognised that the mechanical behaviour of a column under load is influenced by geometry, as well as by material properties; it is clear that the spinal column also obeys these well-described laws. 相似文献