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51.
OBJECTIVES: Liver biopsy is a valuable clinical tool, but for the interpretation to be meaningful a certain core size should be obtained. This study examines the changes the liver biopsy core undergoes during processing steps. METHODS: A total of 61 consecutive percutaneous liver biopsies were obtained between November 2004 and April 2005. The needle type utilized was the 16-gauge automatic tru-cut. A measurement was made while each liver biopsy core specimen resided in the cartridge, then a measurement was made with the core placed on the tray, and a final measurement was made after the pathologist received the formalin-fixed specimen. RESULTS: The mean size of the biopsy core in the cartridge measured 15 +/- 2 mm, compared to a mean size on the tray of 19.6 +/- 3.5 mm, and a mean size after fixation of 18.3 mm. All mean sizes were statistically different from one another. The compressive effect of the cartridge was 23%. The shrinkage effect of formalin fixation was 7%. CONCLUSIONS: The liver biopsy core size changes significantly through the processing steps. It is imperative that the operator is aware of these changes so that appropriate decisions are made. As an example, if the operator underestimates the core size when measured in the cartridge, a second pass may be completed when in fact adequate tissue had been obtained on the first pass. 相似文献
52.
John Hicks Anthony Dilley Dimple Patel James Barrish Shen-Hua Zhu Mary Brandt 《Ultrastructural pathology》2013,37(4):321-333
Lipoblastoma is a relatively rare tumor that occurs in infancy and early childhood and arises from embryonic white fat. Although a benign tumor, lipoblastomas tend to recur and may resemble myxoid liposarcoma. The authors report 26 cases over a 15-year period at Texas Children's Hospital. There was a slight female predilection (14F:12M). The most common symptom was a painless mass with or without increasing size. The trunk, extremities, head and neck, retroperitoneum, inguinal canal, peritoneal cavity, and lung were the tumor sites. Most tumors were circumscribed lipoblastomas and the minority were diffuse infiltrative lipoblastomatosis. Reexcision for residual or recurrent tumor was necessary more frequently in patients with lipoblastomatosis. Histopathologic examination and ultrastructural examination revealed cellular neoplasms composed of immature adipocytes with relatively well-defined septa, frequent lipoblasts, a fine vascular network, and often a myxoid appearance resembling myxoid liposarcoma. Cytogenetics was performed in 4 cases with chromosome 8q abnormality being most common. The major concern with lipoblastoma in children is to completely excise the tumor to avoid leaving residual tumor and to prevent recurrences. Confusion with myxoid liposarcoma, well-differentiated liposarcoma, and typical lipomas may occur. Although asymptomatic, lipoblastomas may cause dysfunction of other organ systems due to mass effect. Complete surgical excision with at least 2 years of follow-up is the preferred therapy. 相似文献
53.
John Hicks Andrew De Jong James Barrish Shen-Hua Zhu Edwina Popex 《Ultrastructural pathology》2013,37(1):79-83
Kniest dysplasia is an autosomal-dominant chondrodysplastic condition characterized by disproportionate dwarfism, short trunk, small pelvis, kyphoscoliosis, short limbs, prominent joints, premature osteoarthritis, and craniofacial manifestations. The craniofacial abnormalities include tracheomalacia, midface hypoplasia, cleft palate, early onset myopia, retinal detachment, prominent eyes, and sensorineural hearing loss. Radiologic features include dumbbell-shaped femora, platyspondylia with anterior wedging of vertebral bodies, coronal clefts of thoracolumbar vertebral bodies, low broad ilia, and short tubular bones with broad metaphyses and deformed large epiphyses. This form of chondrodysplasia is associated with mutations in type II collagen splicing sequences. Mutations have been identified in the COL2A1 (type II collagen) gene between exons 12 and 24. Type II collagen is the predominant structural protein in cartilage, and mutations in this collagen account for the Kniest dysplasia phenotype. Histopathologic and ultrastructural features of epiphyseal plate cartilage have been described, but tracheal cartilage in an affected neonate has not been examined. The authors report the histopathologic and ultrastructural findings of anterior tracheal cartilage from a 35-day-old female with suspected chondrodysplasia who had tracheomalacia with airway obstruction. The tracheal cartilage was moderately cellular, but lacked cystic and myxoid changes in its matrix. The chondrocytes had abundant cytoplasmic PAS-positive inclusions. Some of these inclusions were diastase-resistant and were also highlighted on Alcian blue staining. Ultrastructural examination revealed chondrocytes with greatly dilated rough endoplasmic reticulum containing granular proteinaceous material. There were also frequent aggregates of typical glycogen. The defect in the COL2A1 gene is secondary to mutations, especially at splice junctions, and this markedly disrupts triple helix formation. The mutated type II procollagen results in intracellular retention within the chondrocytes, as abundant granular proteinaceous material within the dilated RER. A relationship is known to exist between the proportion of mutated to normal type II collagen in the matrix and the severity of the phenotype. With low levels of normal type II collagen, the phenotypic manifestations become more severe, such as in achondrogenesis type II. Both the quantity and quality of type II collagen modulates the phenotypic expression of type II collagenopathies. 相似文献
54.
目的 以病理诊断为标准评价双源CT增强扫描定性和定量冠状动脉钙化斑块的准确性。 方法 采用双源CT对离体冠状动脉进行0.6 mm层厚横断面增强扫描,将CT值>130 HU的斑块定性为钙化斑块,依据钙化斑块在管壁横断面上的弧度将其分为3型:轻度钙化、中度钙化和重度钙化。计算钙化斑块导致的冠状动脉狭窄,并与病理分型和所测冠状动脉狭窄进行对比。 结果 病理切片发现钙化斑块69个,DSCT发现57个,双源CT检测轻度、中度和重度钙化斑块的敏感性分别为88.3%、100%和100%。与病理诊断结果相比,双源CT高估了轻度、中度和重度钙化斑块导致的冠状动脉狭窄程度,分别相差(3.2±2.0)%、(4.9±4.7)%和(14.7±8.2)%,P<0.05。 结论 双源CT增强扫描能够检测定性不同类型的冠状动脉钙化;与病理对比,双源CT高估了钙化斑块导致的冠状动脉狭窄程度较严重。 相似文献
55.
56.
目的探讨儿童卵巢幼年颗粒细胞瘤(JGCTs)超声表现及病理特征。 方法回顾性分析2005年1月至2020年12月经重庆医科大学附属儿童医院手术病理证实为JGCTs的14例患儿的临床资料。依据国际卵巢肿瘤分析组织(IOTA)标准对瘤体超声图像进行模式分型,并与术后组织病理结果进行对照分析。 结果14例患儿肿瘤最大径线范围37~286 mm,最大径线平均值(105±56)mm。超声声像图表现为:实性6例(42.9%)、多房囊实性4例(28.6%)、单房囊实性1例(14.3%)、多房囊性2例(14.3%)以及单房囊性1例(7.1%)。病理结果显示,实性包块由大量颗粒细胞弥漫增生形成,其间伴有散在大小不等滤泡、坏死出血及纤维条索组织。多房囊实性、单房囊实性、多房囊性及单房囊性肿瘤内均可见数量不一的大滤泡,滤泡内大多数为颗粒细胞分泌的嗜碱性、嗜酸性液体。临床表现为乳房增大5例(35.7%),阴道出血及分泌物5例(35.7%);超声提示子宫增大10例(71.4%)。所有患儿术前血清雌二醇水平均升高,均值(534.0±839.5)pmol/L。 结论JGCTs超声表现多样,实性和多房囊实混合性更常见,其病理特征为大量颗粒细胞弥漫增生伴散在大小不等滤泡,超声表现结合内分泌临床表现及血清雌二醇的升高有助于临床诊断。 相似文献
57.
Sierra Nevada of Santa Marta is one of the most endemic regions of Chagas disease in Colombia. In this study, we compared the biological behavior and genetic features of Trypanosoma cruzi stocks that were isolated from domestic and sylvatic insects in this area. Rhodnius prolixus (from domestic environments) and Triatoma dimidiata (from sylvatic, peridomestic and domestic environments) are the most important vectors in this region. Genetic characterization showed that all stocks corresponded to T. cruzi I, but LSSP-PCR analyses indicated that some genotypes were present in both environments. Biological characterization in vitro showed a low growth rate in sylvatic T. cruzi stocks and in some domestic T. cruzi stocks, possibly indicating the presence of stocks with similar behavior in both transmission cycles. In parallel, in vivo behavioral analysis also indicated that T. cruzi stocks are variable and this species did not show a correlation between the environments where they were isolated. In addition, all stocks demonstrated a low mortality rate and histopathological lesions in heart, skeletal muscle and colon tissue. Moreover, our data indicated that experimentally infected chagasic mice displayed a relation between their myocardial inflammation intensity, parasitism tissue and parasite load using the qPCR.In conclusion, our results indicate that the T. cruzi stocks present in SNSM have similar biological behavior and do not show a correlation with the different transmission cycles. This could be explained by the complex transmission dynamics of T. cruzi in Sierra Nevada of Santa Marta, where hosts, vectors (e.g., T. dimidiata) and reservoirs circulate in both environments due to the close contact between the two transmission cycles, favoring environment overlapping. This knowledge is an important key to understanding the epidemiology and pathology of Chagas disease in this Colombian region. Furthermore, our findings could be of significant use in the design of control strategies restricted to a specified endemic region. 相似文献
58.
目的 探讨体表血管平滑肌瘤(CAL)的彩色多普勒超声声像图特点与病理学的关系.方法 收集经手术及病理证实的25例CAL,分析病变位置、形态、边界、内部及后方回声等超声征象,CDFI观察包块内部血流分布情况,并分析肿块的超声表现与组织病理学的关系.结果 超声检查发现,CAL以下肢最多见(17/25,68.00%).超声表现为位于皮下组织或真皮深层内的椭圆形、类圆形结节,边界清晰,以低回声为主(23/25,92.00%).17例(17/25,68.00%)肿块内部可见彩色血流信号,以Alder Ⅲ级者为主(10/17,58.82%);Alder 0级者,以实体型为主(6/8,75.00%).结论 CAL为好发于肢体皮下边界清晰的实性低回声肿块,多伴较丰富的血流信号.CAL声像图表现与组织病理学特征密切相关. 相似文献
59.
Maria Teresa B C Bonanomi Osmar C Saito Patricia Picciarelli de Lima Roberta Chizzotti Bonanomi Maria Cristina Chammas 《Clinics (S?o Paulo, Brazil)》2015,70(12):797-803
OBJECTIVE:
To analyze the flow of retrobulbar vessels in retinoblastoma by color Doppler imaging.METHODS:
A prospective study of monocular retinoblastoma treated by enucleation between 2010 and 2014. The examination comprised fundoscopy, magnetic resonance imaging, ultrasonography and color Doppler imaging. The peak blood velocities in the central retinal artery and central retinal vein of tumor-containing eyes (tuCRAv and tuCRVv, respectively) were assessed. The velocities were compared with those for normal eyes (nlCRAv and nlCRVv) and correlated with clinical and pathological findings. Tumor dimensions in the pathological sections were compared with those in magnetic resonance imaging and ultrasonography and were correlated with tuCRAv and tuCRVv. In tumor-containing eyes, the resistivity index in the central retinal artery and the pulse index in the central retinal vein were studied in relation to all variables.RESULTS:
Eighteen patients were included. Comparisons between tuCRAv and nlCRAv and between tuCRVv and nlCRVv revealed higher velocities in tumor-containing eyes (p<0.001 for both), with a greater effect in the central retinal artery than in the central retinal vein (p=0.024). Magnetic resonance imaging and ultrasonography measurements were as reliable as pathology assessments (p=0.675 and p=0.375, respectively). A positive relationship was found between tuCRAv and the tumor volume (p=0.027). The pulse index in the central retinal vein was lower in male patients (p=0.017) and in eyes with optic nerve invasion (p=0.0088).CONCLUSIONS:
TuCRAv and tuCRVv are higher in tumor-containing eyes than in normal eyes. Magnetic resonance imaging and ultrasonography measurements are reliable. The tumor volume is correlated with a higher tuCRAv and a reduced pulse in the central retinal vein is correlated with male sex and optic nerve invasion. 相似文献60.
目的 探讨BALB/c小鼠心肌梗死(MI)后弹性模量与心肌结构和心功能的相关变化。方法 分别于小鼠MI后1小时、24小时、7天、14天和28天,行心脏功能和左心室腔内压力检测;应用原子力显微镜检测梗死心肌弹性模量;梗死心脏组织制成石蜡切片行苏木素-伊红染色和Mallary纤维染色。结果 (1)梗死后心肌弹性模量呈现先降低后逐渐增高的时间依赖性变化。(2)组织病理染色显示,心脏结构与心肌弹性的变化在时间上呈对应关系。(3)心肌梗死后心脏功能和左心室腔内压力的改变表现出与上述理化参数相似的变化趋势。结论 小鼠心肌梗死后弹性模量、心肌结构和功能均表现出时间依赖性相关变化且相互之间保持高度的一致性。 相似文献