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61.
62.
A review on the molecular diagnostics of Lynch syndrome: a central role for the pathology laboratory
63.
目的探讨鼻眶脑毛霉菌病(ROCM)的临床与病理特征,提高对该病的认识和病理诊断水平。方法回顾分析首都医科大学附属北京同仁医院1998~2008年16例ROCM患者的病历资料。用HE、PAS和GMS染色显示组织病变特点及真菌的形态特征,对1例石蜡组织行透射电镜观察。结果 14例(87.5%)有基础疾病,2例(12.5%)无特殊病史。死亡5例(31.3%),3例死于ROCM,2例死于原发病。CT示鼻腔鼻窦软组织密度影16例,MRI示眶内(15例)和颅内(5例)异常信号影。真菌培养7例阳性(43.8%)。组织病理:16例均见组织凝固性坏死、真菌性血管炎及肉芽肿,骨质破坏9例,外周神经纤维坏死7例。特殊染色菌丝形态均符合毛霉目真菌;透射电镜见菌丝形态不规则,菌壁电子密度高。结论 ROCM主要见于糖尿病和血液系统恶性肿瘤者,亦见于无基础疾病者。常见致病菌为根霉和毛霉。在病变组织中找到符合毛霉目真菌形态特点的菌丝可确诊。对临床症状、影像学、真菌培养及病理学表现等多方面进行综合分析可明确诊断。 相似文献
64.
65.
Regina Alemany Javier S. Perona Emilio Montero Ricardo Bressani Valentina Ruiz-Gutierrez 《生物化学与生物物理学报:生物膜》2007,1768(4):964-975
Cells, tissues and organs undergo phenotypic changes and deteriorate as they age. Cell growth arrest and hyporesponsiveness to extrinsic stimuli are all hallmarks of senescent cells. Most such external stimuli received by a cell are processed by two different cell membrane systems: receptor tyrosine kinases (RTKs) and G protein-coupled receptors (GPCRs). GPCRs form the largest gene family in the human genome and they are involved in most relevant physiological functions. Given the changes observed in the expression and activity of GPCRs during aging, it is possible that these receptors are directly involved in aging and certain age-related pathologies. On the other hand, both GPCRs and G proteins are associated with the plasma membrane and since lipid-protein interactions regulate their activity, they can both be considered to be sensitive to the lipid environment. Changes in membrane lipid composition and structure have been described in aged cells and furthermore, these membrane changes have been associated with alterations in GPCR mediated signaling in some of the main health disorders in elderly subjects. Although senescence could be considered a physiologic process, not all aging humans develop the same health disorders. Here, we review the involvement of GPCRs and their lipid environment in the development of the major human pathologies associated with aging such as cancer, neurodegenerative disorders and cardiovascular pathologies. 相似文献
66.
养殖乌鳢类立克次体感染的超微病理学研究 总被引:1,自引:0,他引:1
应用电子显微镜技术,观察了养殖乌鳢RLO感染主要内脏器官超微结构病理变化,并初步探讨了发病机制。观察发现:RLO寄生细胞明显肿大,胞质电子密度低,细胞器肿大、溶解,RLO可随肿胀、破裂的细胞进人组织间隙;在一些寄生细胞内尚发现变性的RLO。内脏组织细胞普遍肿大,细胞器分散、稀少,线粒体除明显肿胀、嵴断裂消失外,尚发现坏死性变化即出现致密核心或无定形的电子密度物质;粗面内质网扩张、破裂和脱颗粒;部分细胞内溶酶体增多,胞质内发现明显的髓鞘样结构;核肿大或核固缩、溶解,并可见核内出现髓鞘样结构和核包含物。 相似文献
67.
The type species of Apiognomonia, A. veneta, with its Discula anamorph is distinct from A. errabunda
Mikhail V. Sogonov Lisa A. Castlebury Amy Y. Rossman James F. White 《Mycological Research》2007,111(6):693-709
Species of Apiognomonia with their Discula anamorphic states in the Gnomoniaceae, Diaporthales, are known throughout the temperate Northern Hemisphere and cause diseases such as sycamore or plane tree anthracnose. The genus Apiognomonia was described based on A. veneta as the type species; however, there has been disagreement about whether or not A. veneta is a synonym of A. errabunda. Using morphological, ecological, and DNA sequence data we conclude that A. errabunda and A. veneta are different species, although very closely related; thus, A. veneta is the correct name for the type species of Apiognomonia. This conclusion is based on a combined analysis of sequences from the ITS regions of nuclear rDNA for 51 isolates from host plants of eight genera and intron regions from actin, calmodulin and translation elongation factor 1-alpha for over 25 isolates. The type species of the genus Discula is D. nervisequa, the earliest available epithet for D. platani, the lectotype of Discula. D. nervisequa is the anamorph of A. veneta. Based on an examination of the type specimen, we determined that the commonly used name for the anamorph of A. errabunda, D. umbrinella, refers to another species. A. veneta and A. errabunda including their anamorphs are described and illustrated. An account of all synonyms and excluded synonyms is presented. 相似文献
68.
P. V. Kumar A. Monabati A. R. Raseki C. Arshadi S. A. Malek-Hosseini A. R. Talei E. Sadeghi 《Cytopathology》2007,18(3):151-156
OBJECTIVE: To study fine needle aspiration (FNA) cytological findings of splenic lesions and assess the role of FNA in the diagnosis of splenomegaly or splenic tumours. METHODS: This study consisted of 48 cases, 25 males and 23 females. The ages ranged between 3 and 71 years. Most of these cases were aspirated under ultrasonographic guidance and a small number were also aspirated directly by using a 22- to 23-gauge needles. The smears were stained with Wright-Giemsa and Papanicolaou methods. Special stains were used whenever necessary. RESULTS: In this study 14 cases were diagnosed as lymphoma-leukaemia, 7 cases as tuberculosis, 12 cases as kala-azar, 2 cases as hydatid cyst, 3 cases as storage diseases, 3 cases as simple cyst, 2 cases as myeloproliferative disorders, 2 cases as malignant tumours and 3 cases as hamartomas (these were wrongly diagnosed as malignant tumours). CONCLUSION: Splenic aspiration is a safe procedure and is very useful in the diagnosis of parasitic and infectious diseases, especially in endemic countries like Iran. 相似文献
69.
探索病理学教学改革,培养高素质医学人才 总被引:8,自引:0,他引:8
病理学是医学院校的重要基础课,高质量的病理学教学是培养高素质医学人才的必要基础。从更新教学内容,科学运用新的教学方法及多种现代化教学手段等方面探讨了当代病理学教学改革。 相似文献
70.
Koji Kageyama Masako Senda Takahiro Asano Haruhisa Suga Kiyoshi Ishiguro 《Mycological Research》2007,111(4):416-423
Heterogeneity of the rDNA ITS region in Pythium helicoides and the phylogenetic relationship between P. helicoides and closely related species were investigated. In PCR-RFLP analysis of the rDNA ITS region of six P. helicoides isolates investigated, including the type culture, intraspecific variation was found at the HhaI site. The total length of fragments was longer than before cutting, indicating sequence heterogeneity within isolates. Digestion of the cloned rDNA ITS region derived from seven isolates with HhaI revealed polymorphisms among and within single zoospore isolates, and variability of the region was also present among the clones derived from the same isolate. To test whether the rDNA ITS region of closely related species and other regions in the genome of P. helicoides are also variable, the rDNA ITS region of P. ultimum and the cytochrome oxydase II (cox II) gene encoded in mitochondria were sequenced. P. ultimum had little variation in the rDNA ITS region. The cox II gene sequences of both species revealed only a low intraspecific variability and no intra-isolate variation. In the phylogenic tree based on the rDNA ITS sequences, all clones of P. helicoides formed one large clade that was distinct from the clades comprising morphologically similar species, such as P. oedochilum and P. ostracodes, and was closely related to P. chamaehyphon rather than the other species. 相似文献