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排序方式: 共有1631条查询结果,搜索用时 31 毫秒
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David G Hicks Brian J Yoder Sarah Short Shannon Tarr Nichole Prescott Joseph P Crowe Andrea E Dawson G Thomas Budd Steven Sizemore Muzaffer Cicek Toni K Choueiri Raymond R Tubbs Daniel Gaile Norma Nowak Mary Ann Accavitti-Loper Andra R Frost Danny R Welch Graham Casey 《Clinical cancer research》2006,12(22):6702-6708
PURPOSE: This study aims to determine the effect of loss of breast cancer metastasis suppressor 1 (BRMS1) protein expression on disease-free survival in breast cancer patients stratified by estrogen receptor (ER), progesterone receptor (PR), or HER2 status, and to determine whether loss of BRMS1 protein expression correlated with genomic copy number changes. EXPERIMENTAL DESIGN: A tissue microarray immunohistochemical analysis was done on tumors of 238 newly diagnosed breast cancer patients who underwent surgery at the Cleveland Clinic between January 1, 1995 and December 31, 1996, and a comparison was made with 5-year clinical follow-up data. Genomic copy number changes were determined by array-based comparative genomic hybridization in 47 breast cancer cases from this population and compared with BRMS1 staining. RESULTS: BRMS1 protein expression was lost in nearly 25% of cases. Patients with tumors that were PR negative (P=0.006) or HER2 positive (P=0.039) and <50 years old at diagnosis (P=0.02) were more likely to be BRMS1 negative. No overall correlation between BRMS1 staining and disease-free survival was observed. A significant correlation, however, was seen between loss of BRMS1 protein expression and reduced disease-free survival when stratified by either loss of ER (P=0.008) or PR (P=0.029) or HER2 overexpression (P=0.026). Overall, there was poor correlation between BRMS1 protein staining and copy number status. CONCLUSIONS: These data suggest a mechanistic relationship between BRMS1 expression, hormone receptor status, and HER2 growth factor. BRMS1 staining could potentially be used in patient stratification in conjunction with other prognostic markers. Further, mechanisms other than genomic deletion account for loss of BRMS1 gene expression in breast tumors. 相似文献
3.
We report an unusual case of primary cutaneous embryonal rhabdomyosarcoma presenting as a solitary skin lesion on the anterior chest of a 20-month-old child. The tumor was characterized by small, round to oval, poorly differentiated cells. Immunohistochemically, the tumor was negative for NSE, S-100 protein, LCA, and keratin but positive for muscle-specific actin, myoglobin, desmin, and vimentin, thus indicating the presence of myogenous differentiation. Ultrastructural analysis demonstrated thick and thin filaments. Special studies showed no evidence of a primary rhabdomyosarcoma in the patient at a more typical location, nor was there any evidence of metastases. 相似文献
4.
Total anorectal reconstruction with a double dynamic graciloplasty after abdominoperineal reconstruction for low rectal cancer 总被引:7,自引:3,他引:4
Bastiaan P. Geerdes M.D. Frans A. N. Zoetmulder M.D. Ph.D Erik Heineman M.D. Ph.D. Egbert J. Vos M.Sc. Mart -Jan Rongen M.D. Cor G. M. I. Baeten M.D. Ph.D. 《Diseases of the colon and rectum》1997,40(6):698-705
PURPOSE: Total anorectal reconstruction with a double dynamic graciloplasty was performed after abdominoperineal reconstruction
(APR) for low rectal cancer. In four patients an additional pouch was constructed to improve neorectal motility and capacity.
The aim of this study was to evaluate the results in the first 20 patients and to report on the preliminary results of patients
with an additional pouch. METHODS: Twenty patients with a mean age of 52 (range, 25–71) years and a rectal tumor at a mean
of 3 (range, 0–5) cm from the anal verge were treated. In 14 patients the Miles resection, colon pull-through, and construction
of a neosphincter were performed in one session. Six patients had the double graciloplasty at an average of 4.1 (range, 1.1–8.8)
years after APR. In four patients a pouch was constructed with an isolated segment of distal ileum. RESULTS: After a mean
follow-up of 24 (range, 1–60) months after APR, none of the patients developed local recurrence, whereas four patients developed
distant metastasis. Fifteen of 20 patients were available for evaluation, and 5 patients were still in training. Of these
15 patients, 8 patients were continent (53 percent), 2 patients were incontinent, and in 5 patients the perineal stoma was
converted to an abdominal stoma. Failures were attributable to necrosis of the colon stump (n=2) and incontinence (n=3). At
26 weeks mean resting pressure was 44 (standard deviation (SD), 28) mmHg, and mean pressure during stimulation was 90 (SD,
46) mmHg at a mean of 35 (SD, 1.2) volts at 52 weeks. Mean defecation frequency was three times per day (range, 1–5). Of the
eight patients who were continent, six used daily enemas. Mean time to postpone defecation was 11 (range, 0–30) minutes. CONCLUSION:
In experienced hands, the double dynamic graciloplasty is an oncologically safe procedure that can have an acceptable functional
outcome in a well-selected group of patients. However, to improve the outcome, further modifications will be necessary. So
far, the addition of a pouch has not resulted in improved outcome.
Supported by the Profileringsfonds of the Maastricht University Hospital, The Netherlands, and by the Stichting Fondsenwervingsactie
Volksgezondheid, Amsterdam, The Netherlands.
Read in part at the meeting of The American Society of Colon and Rectal Surgeons, Seattle, Washington, June 9 to 14, 1995. 相似文献
5.
Five patients with orbital pseudotumor refractive to initial therapy are discussed. Three had a destructive granulomatous process associated with a sclerosing component. Two exhibited a predominantly lymphocytic infiltration. Chemotherapy with Prednisone (100 mg/day) and either Cytoxan (100 mg/day) or Chlorambucil (10 mg/day) in 5-day pulses is described. All patients responded clinically to this treatment without unfavorable side effects. 相似文献
6.
7.
Retroviral vectors derived from murine leukemia virus (MLV) have been pseudotyped with a variant of the envelope glycoprotein (Env) of nonpathogenic simian immunodeficiency virus from African green monkeys (SIVagm) to result in [MLV(SIVagm-wt)] vector particles. The variant env gene encodes a full-length surface envelope glycoprotein (SU) and a C-terminally truncated transmembrane protein (TM). To change the coreceptor usage of this vector from CCR5 to CXCR4, which is predominant on human CD4-positive lymphocytes, the putative V3-loop of SIVagm SU was replaced by that of the T cell tropic HIV-1 variant BH10. The resulting [MLV(SIVagm-X4)] vectors were shown to specifically transduce CD4/CXCR4-positive cell lines, demonstrating the equivalent function in cell entry and choice of coreceptor usage of the V3-loops of SIVagm and HIV-1. These modified vectors were able to transduce primary human lymphocytes and were resistant to neutralization by sera from HIV-1-infected individuals. The [MLV(SIVagm-X4)] pseudotype vector generated is thus a promising candidate vector, e.g., for in vivo gene therapy of HIV-1 infection. 相似文献
8.
Poly(lactide-co-glycolide) microspheres as a moldable scaffold for cartilage tissue engineering 总被引:2,自引:0,他引:2
This study demonstrates the use of biodegradable poly(lactide-co-glycolide) (PLG) microspheres as a moldable scaffold for cartilage tissue engineering. Chondrocytes were delivered to a cylindrical mold with or without PLG microspheres and cultured in vitro for up to 8 weeks. Cartilagenous tissue formed using chondrocytes and microspheres maintained thickness, shape, and chondrocyte collagen type II phenotype, as indicated by type II collagen staining. The presence of microspheres further enhanced total tissue mass and the amount of glycosaminoglycan that accumulated. Evaluation of microsphere composition demonstrated effects of polymer molecular weight, end group chemistry, and buffer inclusion on tissue-engineered cartilage growth. Higher molecular weight PLG resulted in a larger mass of cartilage-like tissue formed and a higher content of proteoglycans. Cartilage-like tissue formed using microspheres made from low molecular weight and free carboxylic acid end groups did not display increases in tissue mass, yet a modest increased proteoglycan accumulation was detected. Microspheres comprised of PLG with methyl ester end groups yielded a steady increase in tissue mass, with no real increase in matrix accumulation. The microencapsulation of Mg(OH)(2) had negative effects on tissue mass and matrix accumulation. The data herein reflect the potential utility of a moldable PLG-chondrocyte system for tissue-engineering applications. 相似文献
9.
Samei E Buhr E Granfors P Vandenbroucke D Wang X 《Physics in medicine and biology》2005,50(15):3613-3625
The modulation transfer function (MTF) is well established as a metric to characterize the resolution performance of a digital radiographic system. Implemented by various laboratories, the edge technique is currently the most widespread approach to measure the MTF. However, there can be differences in the results attributed to differences in the analysis technique employed. The objective of this study was to determine whether comparable results can be obtained from different algorithms processing identical images representative of those of current digital radiographic systems. Five laboratories participated in a round-robin evaluation of six different algorithms including one prescribed in the International Electrotechnical Commission (IEC) 62220-1 standard. The algorithms were applied to two synthetic and 12 real edge images from different digital radiographic systems including CR, and direct- and indirect-conversion detector systems. The results were analysed in terms of variability as well as accuracy of the resulting presampled MTFs. The results indicated that differences between the individual MTFs and the mean MTF were largely below 0.02. In the case of the two simulated edge images, all algorithms yielded similar results within 0.01 of the expected true MTF. The findings indicated that all algorithms tested in this round-robin evaluation, including the IEC-prescribed algorithm, were suitable for accurate MTF determination from edge images, provided the images are not excessively noisy. The agreement of the MTF results was judged sufficient for the measurement of the MTF necessary for the determination of the DQE. 相似文献
10.
Differential diagnosis of Kaposi's sarcoma 总被引:1,自引:0,他引:1
W Blumenfeld B M Egbert R W Sagebiel 《Archives of pathology & laboratory medicine》1985,109(2):123-127
The biopsies of all lesions clinically thought to be suspicious for Kaposi's sarcoma (KS) were reviewed over a 15-month period. A diagnosis of KS was made in 40 of 106 biopsies (38%). The cases in which a diagnosis other than KS was made included dermatofibroma, hemangioma, and scar. This second group comprised 59 of 106 cases (56%). A third group included some lesions that had an atypical vascular proliferation, but in which the changes were insufficient for a definite diagnosis of KS. The presence of abnormally shaped vessels, especially those classified as irregular, was the best single criterion to diagnose KS in its early stages. In later stages, the neoplasm assumes a nodular configuration with typical, slitlike vascular channels. At the periphery of such nodules dilated, irregularly shaped vessels similar to those of the early lesions are often seen. The histologic features which help in the diagnosis of KS from other histologic entities are reviewed. 相似文献