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排序方式: 共有2186条查询结果,搜索用时 15 毫秒
91.
Daly RJ Gu H Parmar J Malaney S Lyons RJ Kairouz R Head DR Henshall SM Neel BG Sutherland RL 《Oncogene》2002,21(33):5175-5181
Grb2-associated binder 2 (Gab2) is a recently identified member of the Gab/Daughter of sevenless family of docking proteins, which localize, amplify and integrate signaling pathways activated by various receptors including receptor tyrosine kinases (RTKs). To date, Gab2 signaling has been primarily investigated in hematopoietic cells. Here we report marked overexpression of Gab2 in a subset of breast cancer cell lines relative to normal breast epithelial strains and a trend for increased Gab2 expression in estrogen receptor (ER)-positive lines. Overexpression relative to normal ductal epithelium was also observed in some primary breast cancers. In MCF-7 breast cancer cells Gab2 was markedly tyrosine phosphorylated in response to heregulin and also following EGF, insulin or bFGF administration, indicating that a variety of RTKs implicated in breast cancer development or progression couple to this docking protein. In hormone-responsive breast cancer cells, GAB2 mRNA and protein expression were induced by estradiol in a manner sensitive to the pure anti-estrogen ICI 182780, indicating that this regulation is mediated via the ER. Gab2 therefore represents a novel link between steroid and growth factor signaling in breast cancer, and when overexpressed, may modulate the sensitivity of breast cancer cells to these important growth regulators. 相似文献
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A case of double aneuploidy involving chromosome 21 and Y is reported in an eight-month-old infant with developmental delay
and failure to thrive. Patient had all classical phenotypical features of trisomy 21 except, absence of epicanthal folds.
The diagnosis was confirmed by cytogenetic study performed on peripheral blood leucocyte culture using G-banding. Literature
review revealed only 17 cases of XYY and trisomy 21 reported so far. No such case is reported in Indian literature. Relevant
literature is reviwed and possible effects of trisomy 21 on XYY and that of XYY on trisomy 21 has been discussed. A routine
chromosomal study even in patient with classical features of Down syndrome has been advocated. Interestingly, our patient
also had left to right shunts at atrial and ductal level and tricuspid regurgitation. Given the rarity of the disorder and
scanty published data the incidence, phenotype and recurrence risk are difficult to establish. 相似文献
94.
Berek JS Bertelsen K du Bois A Brady MF Carmichael J Eisenhauer EA Gore M Grenman S Hamilton TC Hansen SW Harper PG Horvath G Kaye SB Lück HJ Lund B McGuire WP Neijt JP Ozols RF Parmar MK Piccart-Gebhart MJ van Rijswijk R Rosenberg P Rustin GJ Sessa C Thigpen JT Tropé C Tuxen MK Vergote I Vermorken JB Willemse PH 《Gynécologie, obstétrique & fertilité》2000,28(7-8):576-583
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Vibha R. Gujrati PhDa Kirpa Shanker PhDa Satya Vrat MDa Chandravati MSb Surendra S. Parmar PhDa 《American journal of obstetrics and gynecology》1996,175(6):1543-1550
OBJECTIVE: The aim of this study was to explore the relevance of placental monoamine oxidase at the subcellular level in the etiology of the hyperserotonomic state in preeclampsia-eclampsia. STUDY DESIGN: The study was conducted on placentas from 20 normal pregnant women and 25 women with varied severity of preeclampsia-eclampsia. Placental serotonin and subcellular monoamine oxidase activity were determined. Histochemical localization of monoamine oxidase was done in placental sections and cell isolates. RESULTS: Placental serotonin increases with severity (rsystolic 0.84, rdiastolic 0.83) and monoamine oxidase decreases (rsystolic 0.86, rdiastolic 0.79). Placental monoamine oxidase showed marked changes in preeclampsia-eclampsia. Histochemical localization of monoamine oxidase showed diffused low activity evenly throughout the cytoplasm and nucleus of the syncytiotrophoblastic cells in preeclampsia-eclampsia; in contrast, normal placenta showed high activity in the cytoplasm without any activity in the nucleus of syncytiotrophoblastic cells. Detection of monoamine oxidase activity in nuclei of the placenta in preeclampsia-eclampsia is a novel finding. Monoamine oxidase activity at the subcellular level further strengthens this observation. A severity-dependent decrease was present in the nuclei of placentas with preeclampsia-eclampsia. The use of specific substrates and inhibitors revealed the presence of monoamine oxidase in mitochondria and nucleus. CONCLUSION: The study delineates an impaired catabolism of placental serotonin in preeclampsia-eclampsia. The novel appearance of monoamine oxidase in nuclei in proximity to its normal site and low activity resulting in a hyperserotonomic state may lead to preeclampsia-eclampsia. (Am J Obstet Gynecol 1996;175:1543-50.) 相似文献
98.
Duchesne GM Bolger JJ Griffiths GO Trevor Roberts J Graham JD Hoskin PJ Fossâ SD Uscinska BM Parmar MK 《International journal of radiation oncology, biology, physics》2000,47(2):379-388
PURPOSE: To compare the efficacy and toxicity of two hypofractionated radiotherapy schedules for the improvement of local symptoms from muscle-invasive bladder cancer. METHODS AND MATERIALS: A multicenter randomized trial was conducted comparing the efficacy and toxicity of two radiotherapy schedules (35 Gy in 10 fractions and 21 Gy in 3 fractions) for symptomatic improvement in patients considered unsuitable for curative treatment through disease stage or comorbidity. The primary outcome measures were overall symptomatic improvement of bladder-related symptoms at 3 months and changes in bladder- and bowel-related symptoms from pretreatment to end-of-treatment and 3-month assessments. Overall symptomatic improvement was defined prospectively as the improvement in one bladder-related symptom of at least one grade at 3 months, with no deterioration in any other bladder-related symptom. RESULTS: Five hundred patients were recruited, but data on symptomatic improvement at 3 months was only available on 272 patients. Of these, 68% achieved symptomatic improvement (71% for 35 Gy, 64% for 21 Gy), with no evidence of a difference in efficacy or toxicity between the two arms. There was no evidence of a difference in survival between the two schedules (hazard ratio [HR] = 0.99, 95% CI 0.82-1.21, p = 0. 933). CONCLUSION: This is the largest prospective trial to date in the palliative treatment of bladder cancer, and provides baseline data against which other results may be compared. The use of 21 Gy in 3 fractions appears as effective as 35 Gy in 10 fractions, although modest differences in survival, symptomatic improvement rates, and toxicity can not be reliably excluded. 相似文献
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