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During the last 4 yr, fine-needle aspiration cytology (FNAC) has been employed in 1,474 patients in 0-15-yr age group at our institute. Of these, 245 patients were found to have malignant disease, including primitive neuroectodermal tumors, hepatoblastoma, nephroblastoma, sarcoma, and epithelial malignancies. Four metastases from medulloblastoma and two each from astrocytoma and meningioma were confirmed without open biopsy. FNAC interpretation was easy when cytologic findings were correlated with relevant clinical and radiologic data. 相似文献
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Radhika S Bakshi A Rajwanshi A Nijhawan R Das A Kakkar N Joshi K Marwaha RK Rao KL 《Diagnostic cytopathology》2005,32(5):281-286
Malignant renal neoplasms are common solid tumors in pediatric oncology practice. These include the common Wilms' tumor/nephroblastoma and the uncommon neoplasms such as clear-cell sarcoma of the kidney (CCSK), rhabdoid tumor, renal-cell carcinoma, and others. The aim of this study was to describe in detail the cytopathological features of the histopathologically proven uncommon pediatric renal tumors. Aspirates from Wilms' tumor, which are mesenchyme predominant, show clusters of spindle cells associated with the matrix material. Evidence of rhabdomyoblastic differentiation may be present. CCSK, classic subtype, is characterized by round to oval cells arranged perivascularly and also in sheets and clusters intimately associated with a metachromatic matrix mucopolysaccharide material better appreciated in May-Grunwald-Giemsa (MGG)-stained smears. The cells also have more abundant cytoplasm and may show nuclear grooves. Spindle-cell pattern of CCSK is difficult to diagnose on aspiration cytology. Renal-cell carcinoma of childhood shows similar cytological features as its adult counterpart. Rhabdoid tumor of the kidney is characterized by a monomorphic population of cells with abundant cytoplasm, eccentric nuclei with prominent nucleoli. Intrarenal yolk sac tumor is a rare neoplasm and shows severely pleomorphic cells on aspiration.Awareness of these entities is important for the practicing cytopathologist. Further, non-Wilms' renal malignant neoplasms must be distinguished from the common Wilms' tumor so that appropriate chemotherapy protocols may be instituted in cases where the tumor is in an advanced stage of malignancy. 相似文献
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Sau W Cheung Chad A Shaw Wei Yu Jiangzham Li Zhishuo Ou Ankita Patel Svetlana A Yatsenko Mitchell L Cooper Patti Furman Pawel Stankiewicz Pawal Stankiewicz James R Lupski A Craig Chinault Arthur L Beaudet 《Genetics in medicine》2005,7(6):422-432
PURPOSE: We developed a microarray for clinical diagnosis of chromosomal disorders using large insert genomic DNA clones as targets for comparative genomic hybridization (CGH). METHODS: The array contains 362 FISH-verified clones that span genomic regions implicated in over 40 known human genomic disorders and representative subtelomeric clones for each of the 41 clinically relevant human chromosome telomeres. Three or four clones from almost all deletion or duplication genomic regions and three or more clones for each subtelomeric region were included. We tested chromosome microarray analysis (CMA) in a masked fashion by examining genomic DNA from 25 patients who were previously ascertained in a genetic clinic and studied by conventional cytogenetics. A novel software package implemented in the R statistical programming language was developed for normalization, visualization, and inference. RESULTS: The CMA results were entirely consistent with previous cytogenetic and FISH findings. For clone by clone analysis, the sensitivity was estimated to be 96.7% and the specificity was 99.1%. Major advantages of this selected human genome array include the following: interrogation of clinically relevant genomic regions, the ability to test for a wide range of duplication and deletion syndromes in a single analysis, the ability to detect duplications that would likely be undetected by metaphase FISH, and ease of confirmation of suspected genomic changes by conventional FISH testing currently available in the cytogenetics laboratory. CONCLUSION: The array is an attractive alternative to telomere FISH and locus-specific FISH, but it does not include uniform coverage across the arms of each chromosome and is not intended to substitute for a standard karyotype. Limitations of CMA include the inability to detect both balanced chromosome changes and low levels of mosaicism. 相似文献
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Neurosurgical Review - Spinal dysraphism is an umbrella term describing herniation of meninges or neural elements through defective neural arch. They can be broadly categorized into open and closed... 相似文献
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Raminderpal Singh Sibia Ankita Sood Arshula Subedi Anushya Sharma Anirudh Mittal Gaaminepreet Singh Thakur Gurjeet Singh Ravinder Singh Jaura Sanjay Goyal 《Journal of medical virology》2023,95(1):e28152
The present study was designed to check the serum levels of protease-activated receptor (PAR-1) in patients during different phases of dengue severity. Moreover, a correlation between serum PAR-1 levels and hematological parameters, inflammatory cytokine levels, and liver functional changes was also determined. Based on the World Health Organization criteria, the study population was divided into: nonsevere dengue fever (DF; n = 30), severe dengue hemorrhagic fever (DHF; n = 19), and severe dengue shock syndrome (DSS; n = 11). The platelet count (PLT) and hematocrit (HCT) were analyzed using an automated hematology analyzer and liver function enzymes aspartate transaminase (AST), alanine transaminase (ALT), and alkaline phosphate (ALP), bilirubin were checked by auto-analyzer using diagnostic kits. Moreover, the levels of inflammatory mediators C-reactive protein (CRP), tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), interleukin-17 (IL-17), and PAR-1 were determined using respective ELISA kits. The HCT levels were elevated and platelet count decreased significantly during dengue complications (DHF and DSS) compared to the DF patients, while the levels of liver functional biomarkers AST, ALT, ALP, and bilirubin remained elevated in DHF and DSS groups than in the corresponding DF group. Similarly, the inflammatory cytokine levels of CRP, TNF-α, IL-6, and IL-17 in DHF and DSS subjects were markedly increased when observed against DF subjects. Notably, the PAR-1 levels were significantly elevated in DHF and DSS groups than in the DF group and positively correlated with changes in HCT levels, inflammatory biomarkers, and liver enzymes. Our findings conclude that PAR-1 levels persistently increased with the severity of the dengue infection and are strongly associated with various clinical manifestations. Thus, PAR-1 levels can be used as a diagnostic marker for assessing dengue severity. 相似文献
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AIMS: To study the clinical and microbial profile of childhood empyema in South Asia and to identify the changes over the past three decades. METHODS: A total of 265 children (aged 1 month to 12 years) with empyema admitted to the Advanced Pediatric Center, PGIMER, Chandigarh, India in 1989-98, were reviewed retrospectively. RESULTS AND CONCLUSIONS: One third of children were under 5. Culture positivity had decreased significantly (48% v 75%) over the years. Staphylococcus aureus continues to be the commonest (77%) aetiological agent; clustering was seen during hot and humid months (46%). Culture positive Streptococcus pneumoniae cases also decreased (9% v 27%); all were seen during the winter and spring season. Gram negative rods grew in more patients (11% v 7%). Community acquired methicillin resistant S aureus (MRSA) was isolated in three patients. Most children (93%) were treated with parenteral cloxacillin and an aminoglycoside. Tube drainage (TD) was used in 92% of fibropurulent cases, and was successful in 79%. Of 48 patients with failed TD, 12 needed decortication; limited thoracotomy was sufficient in the remaining 36. Surgery was mainly required by children with persistent pleural sepsis after 10 days of TD. Delaying surgery until 14 days had a significantly higher potential of requiring decortication. Early change to oral antibiotics (after 1-2 weeks of parenteral therapy) reduced the hospital stay significantly (17+7 v 23+7 days) without compromising long term outcome. Twenty two patients presenting late in the chronic stage underwent decortication at admission. 相似文献
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Making science relevant to students' lives, future careers, or societies by introducing controversial socio-scientific issues in classrooms motivates students to take more active roles in learning science. This study explored the influence of integrating two sustainability-oriented socio-scientific issues (SOS2Is) - alternative energies and nanotechnology-into the General Chemistry curriculum on 743 students' career aspirations and perceptions of science relevancy. For the presentation of topics, two learning environments on Prezi were prepared. The participants were guided to explore these learning environments that focused on pros and cons of each topic, including environmental and health hazards of technological developments. In addition, students were encouraged to link these discussions to sustainability issues in the context of the UN SDGs. The analysis of Changes in Attitude Towards the Relevancy of Science and Career Aspirations surveys indicated that the interventions improved students' perception of science relevancy and altered their career aspirations in many areas, regardless of their socioeconomic status and ethnic background. This study provides empirical evidence for the effectiveness of discussions around socio-scientific issues in changing students’ perceptions of science and career aspirations and recommends practical methods to encourage students to become global and scientifically literate citizens. 相似文献