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31.
The goals of this chapter in keeping with the overall general themes of this special edition will be (1) to highlight aspects of development of the thyroid and parathyroid glands with particular focus on the role and contribution of the neural crest (or not) and how this may impact on the pathology that is seen, (2) to emphasize those lesions particularly more commonly arising in the pediatric population that actually generate specimens that the surgical pathologist would encounter, and (3) highlight more in depth specific lesions associated with heritable syndromes or specific gene mutations since the heritable syndromes tends to manifest in the pediatric age group. In this light, the other interesting areas of pediatric thyroid disease including medical thyroid diseases, congenital hypothyroidism, anatomic variants and aberrations of development that lead to structural anomalies will not be emphasized here.  相似文献   
32.
A long-standing assumption in molecular biology posits that the conservation of protein and nucleic acid sequences emphasizes the functional significance of biomolecules. These conserved sequences fold into distinct secondary and tertiary structures, enable highly specific molecular interactions, and regulate complex yet organized molecular processes within living cells. However, recent evidence suggests that biomolecules can also function through primary sequence regions that lack conservation across species or gene families. These regions typically do not form rigid structures, and their inherent flexibility is critical for their functional roles. This review examines the emerging roles and molecular mechanisms of “nondomain biomolecules,” whose functions are not easily predicted due to the absence of conserved functional domains. We propose the hypothesis that both domain- and nondomain-type molecules work together to enable flexible and efficient molecular processes within the highly crowded intracellular environment.  相似文献   
33.
Adenohypophyses of human newborns contain characteristic psammoma bodies. Their numbers are maximal within 2 weeks of the neonatal period and diminish thereafter. They are very rare in infant pituitaries, seeming to disappear by shrinkage in that there is a significant direct correlation between their number and size. The bodies were found to contain a high concentration of endogenous peroxidase, thus suggesting that the enzyme may be responsible for their disappearance. A statistical majority of psammoma bodies were located within follicular lumens. By immunohistochemistry, the follicular epithelium surrounding psammoma bodies showed immunoreactivity for various pituitary hormones. Light microscopy demonstrated that adenohypophysial cells surrounding psammoma bodies contain randomly, scattered granules or globules exhibiting peroxidase activity. Extrusion of such granules into follicular lumens may play a role in the genesis of the concretions. The conspicuous lamellar nature of the calcified psammoma bodies suggests that waves of calcium deposition occur during their morphogenesis. Despite histologic similarities, the histochemical characteristics of this type of psammoma body differ from those in other organs as well as from the calcification encountered in prolactin (PRL)-producing pituitary adenomas.  相似文献   
34.
Summary This retrospective study focuses on 14 patients with ganglioglioma of the cerebral hemispheres who received surgical treatment in the Neurosciences Department/Neurosurgery of La Sapienza University of Rome between 1953 and 1990. The data are analyzed together with those on 98 published cases of ganglioglioma confined to the cerebral hemispheres. These tumours have no sex preference but a decided preference for the young (mean age 18 years). They are characterized by a history of epilepsy often of long standing and sometimes refractory to drugs. The most frequent site is the temporal lobe (61%). At operation the tumour proved to be solid in 52% of cases and the satellite cyst at the tumour wall in 48%. Removal was total in 65% of cases. Even after subtotal removal, the prognosis is good in terms both of survival and of seizure control. Radiotherapy seems to have no role in the treatment of these tumours.  相似文献   
35.
Summary An autopsy case of a Japanese male with familial -galactosidase and neuraminidase deficiency is reported. The clinical picture was characterized by adult onset, a gargoyle-like face, cerebellar ataxia, myoclonus, convulsions, retinal degeneration and cortical blindness.Histopathologically, most neurons seemed to have become degenerated in the whole cerebral cortex. Moreover, the calcarine cortex appeared spongy with depopulation of nerve cells. Stuffed neurons or neuronal storage changes were found throughout the brain, especially in the motor nuclei of the spinal cord and brain stem.The inclusions in the stuffed neurons revealed various profiles on the electron microscope. They were composed of membranous lamellar and/or multilamellar structures, often accompanying vacuoles and reminiscent of lipofuscin-like profiles.  相似文献   
36.
肾恶性横纹肌样瘤临床病理分析及超微结构观察   总被引:3,自引:0,他引:3  
目的:探讨肾恶性横纹肌样瘤(MRTK)的临床病理表现及超微结构特点。方法:用光镜、免疫组化及电镜等方法观察其病理组织学特点、免疫组化表达及超微结构。结果:光镜的典型特点是肿瘤细胞弥漫性排列,呈圆形、椭圆形及不规则形,胞质丰富,嗜酸性,部分胞质内可见透明状小体,细胞核圆形或椭圆形,核膜厚,核仁清楚,有的细胞核呈空泡状。部分核偏向一侧似浆细胞样。细胞内外见红染的包涵体。免疫组化显示肿瘤可表达多种抗原。电镜观察特异性表现是胞质内见中间丝及圆形不规则形纤维状或轮状小体。结论:肿瘤细胞弥漫排列呈浆细胞样,免疫组化多方向表达,可向神经性、上皮性、肌性等方向分化。电镜下胞质内中间丝及纤维轮状小体是特异性诊断标志。  相似文献   
37.
王勤 《中国基层医药》2005,12(3):328-329
目的 探讨气管、支气管非金属异物的影像学表现,提高对该病的早期诊断率。方法 回顾性分析了60例气管、支气管非金属异物的临床与影像学征象。结果 本组60例中,右侧支气管异物32例,左侧支气管异物22例,主气管异物6例。常见的影像学表现为阻塞性肺气肿51例,纵隔摆动48例。结论 病史及影像学表现是诊断气管、支气管非金属异物的主要手段。  相似文献   
38.
Corpora amylacea (C.A.) also named polyglucosan bodies (P.B.) are one of the hallmarks of normal brain aging. Although their functions are not yet clear, C.A. increase in number in patients suffering from neurodegenerative diseases. C.A. contain 88% of hexoses and 4% of proteins. Most of the proteins in C.A. are aging or stress proteins such as heat shock proteins, ubiquitinated proteins and advanced glycation end products which are also proinflammatory products. Stimulated by the potential role played by some S100 proteins in the inflammatory process which may be triggered in C.A., we investigated, by immunohistochemistry, the presence of different S100 proteins (S100A1, S100A2, S100A3, S100A4, S100A5, S100A6, S100A8, S100A9, S100A12 and S100B) in C.A. from normal human brain. Among the ten S100 proteins analyzed, nine (S100A) were detected in C.A. Three S100 proteins (S100A8, S100A9, S100A12) which are highly expressed in activated macrophages and used as inflammatory markers were detected in C.A. S100A8 was, in addition, found in thick neuronal processes from the pons. One (S100B) could not be found in C.A. although it was highly expressed in astrocytes. In C.A., the staining intensity was estimated by computer-assisted microscopy and gave the following order: S100A1 congruent withS100A8 congruent with S100A9>S100A5> or =S100A4>S100A12>S100A6> S100A2=S100A3. The potential inflammatory role played by S100 proteins in C.A. is discussed.  相似文献   
39.
目的:探讨后极部眼内异物取出方法。方法:借助眼用粘弹剂(玻璃酸钠)的粘弹性和内聚性,首先将异物包绕、游离、悬浮,然后视异物大小、形状酌情选用自制异物回吸针头或异物钳取出异物。结果:本组17例(17眼)后极部眼内异物,均一次顺利取出,无一发生手术误伤及手术并发症。术后视力提高14眼,不变2眼,下降1眼。结论:借助粘弹剂游离悬浮法取出后极部眼内异物,可显著降低手术难度、手术损伤及手术并发症。尤其是悬浮回吸异物,效果更优。  相似文献   
40.
眼球内异物玻璃体手术治疗结果分析   总被引:12,自引:1,他引:12  
目的 探讨玻璃体手术治疗眼球内异物及其并发症的临床效果。方法 对我院 1999年 1月~ 2 0 0 1年 12月收治的各种眼球内异物 6 2例 6 4眼进行回顾性分析 ,男 5 8例 ,女 4例 ,年龄 8~ 4 6岁 ,平均 2 3岁。除 1例 1眼采用扁平部巩膜切口 ,磁铁吸出异物外 ,其余 6 1例 6 3眼均采用玻璃体切割术。术后视力≥ 0 .0 2作为功能成功的标准 ;术后视力<0 .0 2 ,眼球结构完整 ,作为解剖成功的标准 ,视力≥ 0 .0 5作为脱盲成功的标准。结果 所有眼球内异物均一次手术成功取出。共有 10眼发生眼内炎 ( 15 .6 3% ) ,随访 3~ 36月 (平均 12 .5月 ) ,最终视力 <0 .0 2者 14眼 ,≥ 0 .0 2者 5 0眼 ,≥ 0 .0 5者 36眼 ,≥ 0 .10者 2 5眼 ,≥ 0 .30者 6眼 ,≥ 0 .5 0者 10眼。功能成功率 (VA≥ 0 .0 2 )为 78.79% ,解剖成功率 (VA <0 .0 2 ,眼球结构完整 )为 93.75 % ,总脱盲率 (VA≥ 0 .0 5 )为5 6 .2 5 % .结论 眼内异物的治疗最好采用玻璃体切割术 ,强调尽早手术  相似文献   
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