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Fine needle aspiration cytology of a skeletal metastasis of adult Wilms' tumor. A case report 总被引:2,自引:0,他引:2
BACKGROUND: Nephroblastoma (Wilms' tumor) is the most common malignant tumor of the kidney in children but is rare in adults. The stage and histopathology of the tumor are the most important prognostic indicators. The common sites of metastasis are lung, liver and lymph nodes. Skeletal metastasis is exceedingly rare in both pediatric and adult nephroblastoma. We report an unusual case of a skeletal metastasis of adult nephroblastoma that developed nine years after the diagnosis of a typical nephroblastoma of favorable histology and that was diagnosed by computed tomography (CT)-guided fine needle aspiration cytology. CASE: Following a right radical nephrectomy for adult nephroblastoma and two local recurrences two and three years later, a 74-year-old woman presented with low back pain. CT and magnetic resonance imaging revealed lytic lesions in the 10th and 12th thoracic vertebrae. Smears prepared from specimens obtained through CT-guided fine needle aspiration biopsy were moderately cellular, with small, round cells arranged singly and in loosely cohesive clusters. These cells had inconspicuous nucleoli and scanty to moderate amounts of cytoplasm. The cells were also positive for cytokeratin and vimentin and appeared similar to areas of blastema in the original tumor. CONCLUSION: A definitive diagnosis of metastatic adult nephroblastoma in thoracic vertebrae was made possible by CT-guided fine needle aspiration cytology in conjunction with clinical and radiologic findings and by using ancillary modalities, such as immunohistochemical studies. 相似文献
84.
Delay in sexual maturity of the follicle-stimulating hormone receptor knockout male mouse 总被引:2,自引:0,他引:2
In the highly organized and complex process of mammalian spermatogenesis, the development of an undifferentiated diploid germ cell into a fully differentiated and mature spermatozoon is orchestrated in a time frame unique for each species including man. If the various hormonal signals including environmental cues that play a critical part in initiating these events are not properly executed, various deficiencies including delay in sexual maturity or puberty are likely. In this study we have followed testicular development and spermatogenesis in the FSH receptor knockout (FORKO) mice from Day 7 onward by using histology and quantitative DNA flow cytometry. The drastic reduction in testicular weight and shrinkage of seminiferous tubules that occurred at this early age persisted into the adult stage in the FORKOs, suggesting inhibition of the initial developmental processes. The round spermatids that were clearly abundant on Day 21 in the wild-type and heterozygous males were few and present only in some tubules of the FORKOs. There were no elongated spermatids in FORKO males on Day 35. The sperm produced by Day 49 FORKOs were already aberrant, a feature that persisted into adulthood in these animals. As all these changes occurred in a background of normal circulating testosterone levels, we may conclude that the delay in testicular development is a consequence of the loss of FSH-receptor signaling. The delay in sexual maturity of FORKOs was accompanied by reduction in fertility as evidenced by mating studies. Based on these data we suggest that the FORKO mouse might be a useful experimental model to define the molecular mechanisms that underlie the delay in puberty. 相似文献
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Current statistical methods for estimating nest survival rates assume that nests are identical in their propensity to succeed. However, there are several biological reasons to question this assumption. For example, experience of the nest builder, number of nest helpers, genetic fitness of individuals, and site effects may contribute to an inherent disparity between nests with respect to their daily mortality rates. Ignoring such heterogeneity can lead to incorrect survival estimates. Our results show that constant survival models can seriously underestimate overall survival in the presence of heterogeneity. This paper presents a flexible random-effects approach to model heterogeneous nest survival data. We illustrate our methods through data on redwing blackbirds. 相似文献
87.
Krishnamurthy Ramanarayanan Arrhenius Gustaf Eschenmoser Albert 《Origins of life and evolution of the biosphere》1999,29(4):333-354
Amidotriphosphate (0.1 M) in aqueous solution at near neutral pH in the presence of magnesium ions (0.25 M) converts glycolaldehyde (0.025 M) within days at room temperature into glycolaldehyde phosphate in (analytically) nearly quantitative yields (76% in isolated product). This robust phosphorylation process was observed to proceed at concentrations as low as 30 M glycolaldehyde and 60 M phosphorylation reagent under otherwise identical conditions. In sharp contrast, attempts to achieve a phosphorylation of glycolaldehyde with cyclotriphosphate (trimetaphosphate) as phosphorylating reagent were unsuccessful. Mechanistically, the phosphorylation of glycolaldehyde with amidotriphosphate is an example of intramolecular delivery of the phosphate group. 相似文献
88.
Jagannadham MV Krishnamurthy AS Husain S Nagaraj R 《Indian journal of biochemistry & biophysics》1999,36(6):422-428
The conformations of peptides corresponding to KLLIALVLCFLPLAALG have been examined in trifluoroethanol (TFE), aqueous medium by circular dichroism spectroscopy and in the solid state by Fourier Transform Infra Red Spectroscopy (FTIR). The 17-residue parent peptide and peptides corresponding to shorter segments LVLCFLPLAALG and CFLPLAALG showed preference for helical conformation in TFE. Even the shorter hydrophobic peptides corresponding to KLLIA and LVL showed propensity for beta-turn conformations in TFE. However, peptides corresponding to the relatively polar segment FLPLAALG were unordered in TFE. In water, peptides that showed ordered conformation in TFE preferred beta-conformation. In solid-state, FTIR spectra indicated that the hydrophobic peptides adopt beta-structures with extensive hydrogen bonded network in the solid-state. The hydrophobic core segment thus appears to dictate the conformational propensity of the peptide. 相似文献
89.
Prabhakaran R Geetha A Thilagavathi M Karvembu R Krishnan V Bertagnolli H Natarajan K 《Journal of inorganic biochemistry》2004,98(12):2131-2140
A series of new hexa-coordinated ruthenium(III) complexes of the type [Ru(X)(2-atmp-ba)(EPh3)] (where H2-2-atmp-ba=N,N'-bis(2-aminothiophenol)benzoylacetone; X=Cl or Br; E=P or As) have been prepared by reacting [RuX3(EPh3)3] (where X=Cl or Br; E=P or As) with tetradentate Schiff base ligand (H2-2-atmp-ba) in 1:1 molar ratio. The complexes have been characterized by elemental analyses, Infra red, electronic, electron paramagnetic resonance spectroscopy and cyclic voltammetry. In order to confirm the coordination and structure of the complexes extended X-ray absorption fine structure spectroscopy (EXAFS) studies have been carried out. Based on the above data, an octahedral structure has been confirmed for the complexes. The new complexes were also screened for their antibacterial properties. 相似文献
90.