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61.
Gastrointestinal vascular anomalies are extremely uncommon. We describe a patient with Down syndrome who presented with acute abdominal pain due to a mixed capillary and venous vascular malformation involving the proximal jejunum. 相似文献
62.
A M Gurley J F Silverman M M Lassaletta J E Wiley C T Holbrook V V Joshi 《Diagnostic cytopathology》1992,8(2):137-146
We evaluated the diagnostic contribution of adjunct studies performed on aspirated material in the work-up of pediatric fine-needle aspiration (FNA) biopsies. Ancillary studies were performed on 54 of 136 (39.7%) pediatric FNA biopsies during a 5-year period. In 23 (16.9%) cases, immunocytochemical (ICC) studies, consisting of immunoperoxidase staining of direct smears and/or cell blocks or flow cytometric immunophenotyping, were performed. The studies were adequate in 14 cases (60.9%), suboptimal in five cases (21.7%), and inadequate in four cases (17.4%). Of the adequate and suboptimal cases, the ICC data helped to narrow the differential diagnosis or classify the disease process in eight cases (42.1%), confirmed cytologic impression in nine cases (47.4%), and gave contradictory results in two cases (10.5%). Adequate material for electron microscopy (EM) was obtained in 14/19 cases (73.7%). Ultrastructural studies were diagnostic, or helped classify the disease process in five cases (35.7%), confirmed the cytologic impression in four cases (28.6%), helped exclude diagnostic considerations in three cases (21.4%), and were judged to be non-contributory in two cases (14.3%). Cytogenetic studies revealed six of seven cases (all neoplasms) to have abnormal karyotypes. Special stains for organisms performed on smears from 25 cases including Ziehl-Neelsen, Gomori methenamine silver (GMS), Gram, and Warthin-Starry (WS) were negative except for 1/16 GMS and 4/9 Gram stains. In summary, we found that with appropriate case selection, ancillary studies performed on aspirated material can provide useful information in pediatric FNA cytology. 相似文献
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64.
The existence of subgenomic RNAs is well established in the case of plant viruses such as tobacco mosaic virus (TMV). However, except for the subgenomic coat protein mRNA, it is not known whether the other subgenomic RNAs have a function in the life cycle of the virus. In search of more information about one of the major subgenomic RNAs-intermediate length RNA-2 or I2 RNA-of TMV, in vitro and in vivo translational studies were performed. The I2 RNA, which codes in vitro for the synthesis of a 30K (K = kilodalton) protein, appears to be uncapped as judged by the need of different in vitro translation conditions for the synthesis of this protein, compared to the conditions required for the synthesis of the 126K and 183K proteins coded by the capped genomic RNA. In vivo a protein migrating in the same position as the 30K protein synthesized in vitro can be detected in infected tobacco leaves. Since this protein occurs transiently early upon infection, whether it is virus-coded or virus-induced, it could have an early function during infection. 相似文献
65.
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
66.
DL?MagerEmail author AD?Haffajee PM?Devlin CM?Norris MR?Posner JM?Goodson 《Journal of translational medicine》2005,3(1):27
Background
The purpose of the present investigation was to determine if the salivary counts of 40 common oral bacteria in subjects with an oral squamous cell carcinoma (OSCC) lesion would differ from those found in cancer-free (OSCC-free) controls. 相似文献67.
We investigated the capacity of human interleukin (IL) 7 to induce proliferation of B cells. Purified tonsillar B cells were cultured in the presence of IL7 with Staphylococcus aureus Cowan I (SAC) or anti-μ beads as co-mitogens. IL 7 supported a dose-dependent proliferation of anti-μ-activated B cells but did not significantly support proliferation of SAC-activated B cells. When B cells were separated on Percoll gradient into small (60%-80%) and large (50%–60%) B cells and then cultured with anti-μ beads, IL7 acted on both cell populations equally well. IL7 and BCGF (low molecular weight) were synergistic in their proliferative action on anti-μ-activated B cells in a 5-day culture. On the other hand, synergistic effect of IL 7 on activated B cells was not evident in the presence of any other factor recombinant [(r)IL 1β, rIL2, rIL3, rIL4, rIL5, rIL6, recombinant tumor necrosis factor-α, recombinant lymphotoxin, recombinant granulocyte-monocyte colony-stimulating factor and recombinant interferon-γ] we tested. IL7 did not induce IgG secretion by activated B cells. 相似文献
68.
Foskey M Davis B Goyal L Chang S Chaney E Strehl N Tomei S Rosenman J Joshi S 《Physics in medicine and biology》2005,50(24):5869-5892
In this paper, we present and validate a framework, based on deformable image registration, for automatic processing of serial three-dimensional CT images used in image-guided radiation therapy. A major assumption in deformable image registration has been that, if two images are being registered, every point of one image corresponds appropriately to some point in the other. For intra-treatment images of the prostate, however, this assumption is violated by the variable presence of bowel gas. The framework presented here explicitly extends previous deformable image registration algorithms to accommodate such regions in the image for which no correspondence exists. We show how to use our registration technique as a tool for organ segmentation, and present a statistical analysis of this segmentation method, validating it by comparison with multiple human raters. We also show how the deformable registration technique can be used to determine the dosimetric effect of a given plan in the presence of non-rigid tissue motion. In addition to dose accumulation, we describe a method for estimating the biological effects of tissue motion using a linear-quadratic model. This work is described in the context of a prostate treatment protocol, but it is of general applicability. 相似文献
69.
70.
Serum Adenosine Deaminase (ADA) enzyme levels were estimated in 61 patients with symptoms and signs suggestive of Pulmonary Tuberculosis and correlated with "Gold standards" such as smear positivity of sputum for Acid Fast bacilli, Tuberculin skin testing and Radiological evidence. The mean ADA levels in smear and Tuberculin negative patients was 13.13 +/- 5.97 u/L, while in those with smear and/or strongly positive Tuberculin reaction, the mean levels of ADA were 33.52 +/- 15.22 u/L. The mean serum ADA levels in 25 healthy voluntary donors with no evidence of active or old Tuberculous lesion, were found to be 16.5 +/- 3.18 u/L. The specificity, sensitivity, positive predictive value and negative predictive value of the test was found to be 87%, 71%, 90% and 66.5% respectively. The results conclude that the serum ADA value is sufficiently useful in identifying those patients in whom the diagnosis of Pulmonary Tuberculosis should be actively considered. 相似文献