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11.
B. B. Y. Ma A. Oza E. Eisenhauer† G. Stanimir‡ M. Carey§ W. Chapman¶ E. Latta¶ K. Sidhu J. Powers† W. Walsh† A. Fyles 《International journal of gynecological cancer》2004,14(4):650-658
A multicenter phase II trial was conducted to define the activity of letrozole in postmenopausal women with recurrent or advanced endometrial carcinoma, who had no more than one prior line of progestins and never had chemotherapy (except adjuvant). Archival paraffin-embedded tumor samples were retrieved to determine the expression level of estrogen (ER) and progesterone receptor (PgR), p53, HER-2, bcl-2 and PTEN protein, and phosphorylation status of protein kinase B (PKB/Akt). Thirty-two eligible patients were treated with letrozole at 2.5 mg daily continuously, of whom 10 (31%) had prior progestins. Of the 28 patients evaluated for response, one complete and two partial responses were noted; overall response was 9.4% (95% confidence interval 2-25%). Eleven patients had stable disease for a median duration of 6.7 months (range 3.7-19.3 months). Amongst 22 patients who had tumor blocks available, the proportion showing positive expression of the following markers includes: PgR (86%), ER (86%), PTEN (82%), phosphorylated PKB/Akt (59%), bcl-2 (45%), p53 (32%), and HER-2 (0%). None of these markers correlated with response to letrozole or disease progression. In conclusion, letrozole is well tolerated but has little overall activity in this cohort of women with endometrial cancer. 相似文献
12.
S. Sidhu L. Edwards S. Rainer T. O'Connor 《The Australian & New Zealand journal of obstetrics & gynaecology》1998,38(1):125-127
EDITORIAL COMMENT: We accepted this case report for publication because, apart from being interesting, it raises the question of the appropriate hormone replacement therapy after bilateral oophorectomy (usually with hysterectomy) has been performed when there is evidence of endometriosis. Menopausal symptoms in these women can be relieved by oestrogen therapy without return of pelvic pain or dyspareunia. The authors report a case of endometrial-like carcinoma in a woman with known endometriosis after a hysterectomy and prolonged unopposed oestrogen therapy. Although this is a solitary case report, the authors explain that there are 8 others in the literature where malignancy occurred in extraovarian endometriosis after bilateral oophorectomy associated with unopposed oestrogen. One of our reviewers commented that a combination of oestrogen and progestogen should always be considered when prescribing hormone replacement therapy in women with a known history of endometriosis, following total hysterectomy and bilateral oophorectomy. 相似文献
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A two-site sandwich immunoradiometric assay of human lymphotoxin with monoclonal antibodies and its applications 总被引:1,自引:0,他引:1
A Meager S Parti H Leung J Woolley E Peil S Sidhu T Roberts 《Journal of immunological methods》1987,104(1-2):31-42
Three monoclonal antibodies (MoAbs L49-15, L81-11 and L238-14) were raised against recombinant human lymphotoxin (rLT) derived from E. coli containing the cDNA sequence specifying LT. MoAb L81-11 strongly neutralised the cytotoxicity of LT derived either from E. coli or the RPMI 1788 lymphoblastoid cell line, whilst the other two MoAbs were only weakly neutralising in this respect. L81-11 and L238-14 MoAbs bound to different antigenic determinants on the rLT molecule, but neither bound to other lymphokines such as the structurally related tumour necrosis factor (TNF). As such, these MoAbs were ideal reagents for immunoassay of LT and a very sensitive, highly specific immunoradiometric assay (IRMA) was developed. This assay was rapid to perform and was capable of detecting as little as 10 pg/ml of LT. Application of the LT IRMA in combination with previously developed human gamma-interferon (IFN-gamma) and human TNF-specific IRMA (Crane et al., 1985; Meager et al., 1987) permitted independent estimations of these three substances to be carried out in parallel. By these means, it was found that RPMI 1788 produced both LT and TNF, but not IFN-gamma. Extensive analyses on cytokine (monokine and lymphokine) preparations derived from a variety of activated lymphocytes are also reported. Co-production of LT, TNF and IFN-gamma was a common finding, even occurring in alloantigen-specific T helper cell clones. 相似文献
16.
Among the morphological features of an oncocytic mucoepidermoid carcinoma of the parotid salivary gland in a 78-year-old man, the oncocytes had granular eosinophilic cytoplasm that was characterized ultrastructurally by large numbers of mitochondria that displayed minimal abnormalities. Complex cell-to-cell relationship, well-developed junctival complexes, and microvillous-like surface projections suggestive of ductal differentiation were present; epidermoid features in the form of dense focal aggregates of cytoplasmic fibrils were also seen. 相似文献
17.
Ford EC Chang J Mueller K Sidhu K Todor D Mageras G Yorke E Ling CC Amols H 《Medical physics》2002,29(12):2913-2924
We investigate the potential of megavoltage (MV) cone-beam CT with an amorphous silicon electronic portal imaging device (EPID) as a tool for patient position verification and tumor/organ motion studies in radiation treatment of lung tumors. We acquire 25 to 200 projection images using a 22 x 29 cm EPID. The acquisition is automatic and requires 7 minutes for 100 projections; it can be synchronized with respiratory gating. From these images, volumetric reconstruction is accomplished with a filtered backprojection in the cone-beam geometry. Several important prereconstruction image corrections, such as detector sag, must be applied. Tests with a contrast phantom indicate that differences in electron density of 2% can be detected with 100 projections, 200 cGy total dose. The contrast-to-noise ratio improves as the number of projections is increased. With 50 projections (100 cGy), high contrast objects are visible, and as few as 25 projections yield images with discernible features. We identify a technique of acquiring projection images with conformal beam apertures, shaped by a multileaf collimator, to reduce the dose to surrounding normal tissue. Tests of this technique on an anthropomorphic phantom demonstrate that a gross tumor volume in the lung can be accurately localized in three dimensions with scans using 88 monitor units. As such, conformal megavoltage cone-beam CT can provide three-dimensional imaging of lung tumors and may be used, for example, in verifying respiratory gated treatments. 相似文献
18.
Myoblasts fail to stimulate T cells but induce tolerance 总被引:1,自引:0,他引:1
Warrens Anthony N.; Zhang Jun Yan; Sidhu Sid; Watt Diana J; Lombardi Giovanna; Sewry Caroline A; Lechler Robert I. 《International immunology》1994,6(6):847-853
Recent interest in myoblast transfer and in the use of myoblastsas vehicles in gene therapy has made it important to understandthe potential immunogenicity of allogeneic or neoantlgen-expresslngmyoblasts. Given the problems of producing a pure populationof myoblasts, In this study we used a tumour-derived musclecell line (TE671), with phenotyplc features of myoblasts, whichwe transfected to express HLA-DR1. However, this cell line wasunable to stimulate either established HLA-DR1-specific alloreactlveT cell clones or a primary alloresponse. Nor could it presenthaemagglutlnln peptide HA 306–324 to DR1-restricted, HA306–324-speciflc T cell clones or lines. Indeed, prelncubatlonwith DR1-expressing TE671 and HA 306–324 rendered suchT cells tolerant as Judged by their subsequent inability toproliferate in response to a DR1+ B cell line plus peptide HA306–324. These results imply that myoblasts do not providecostlmulatory signals, and are therefore unlikely to stimulateallospeclfic T cells following myoblasts transplantation orto initiate neoantlgen-speclfic immune responses following Invivo transfection. 相似文献
19.
Pancreatoblastoma is a rare tumor and has been reported only four times in the cytologic literature, three times in fine-needle aspiration (FNA) biopsy and once in an imprint of resected tumor. We are reporting the fourth case of FNA cytology with immunohistochemical and electron microscopic studies. The patient is a 24-yr-old African American woman, who presented with a pancreatic mass, hepatic masses, and abdominal lymphadenopathy. The aspiration smears of the liver mass showed a biphasic tumor composed of bland-appearing primitive spindled stromal fragments with "spider-web"-like long fibrils interconnecting with sharply angulated islands of cohesive epithelium. At high power, the epithelium is composed of medium-sized cells with round-to-oval vesicular nuclei with fine chromatin and one-to-two small nucleoli. The neuroendocrine component was demonstrated immunohistochemically with synaptophysin and chromogranin expressions. The acinar component and squamoid component were demonstrated ultrastructurally by the presence of 400-600 nm zymogen granules and tonofilaments. The literature was reviewed and the cytological features of all the four cases of pancreatoblastoma are summarized. 相似文献
20.
The present study investigated sex differences and the effect of a high level of estradiol in the female meadow vole on performance in the forced swim test (FST) and the Morris water maze in meadow voles. Female meadow voles were ovariectomized (OVX) and administered either vehicle (sesame oil) or estradiol for 2 days prior to performing the FST. Four days following the FST, all animals were run in the Morris water maze. Results indicated that estradiol-injected female meadow voles showed more 'depressive-like' behaviors in the FST (greater time spent immobile and less time spent swimming) than vehicle-treated female or male meadow voles. In addition, estradiol-treated females had impaired performance (greater latencies and distance swam to reach the hidden platform) than both vehicle-treated female and male meadow voles, consistent with previous data. Despite the fact that estradiol administration increased 'depressive-like' behaviors in the FST and impaired performance in the Morris water maze, there was no correlation between the two behaviors indicating that 'depressive-like' behaviors did not account for the differences seen in spatial performance in the Morris water maze. To our knowledge, this is the first demonstration in rodents indicating that estradiol-mediated changes in behavior in the FST is not indicative of subsequent performance in the Morris water maze. 相似文献