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Purpose: The purpose of this study was to evaluate the clinical effectiveness of subcutaneous estradiol pellets in donor oocyte recipients with an inadequate endometrial response. Methods: The subjects were 13 women with ovarian failure and a maximal endometrial thickness <10 mm on standard estrogen regimens, as demonstrated during mock and/or prior oocyte donation cycles. They underwent pellet implantation (100–250 mg of estradiol) 6–13 weeks before oocyte donation. Results: Maximal (mean ± SD) endometrial thickness was 8.7±1.5 mm on standard regimens, in contrast to 11.7± 1.8 mm on pellets, while estradiol levels were 674±844 and 815±706 pg/ml, respectively. The estradiol:estrone ratio on pellets was >1. There was 1 pregnancy with early loss during 10 cycles on other estrogen regimens and 12 pregnancies during 19 cycles on pellets. The pregnancy and implantation rates were, respectively, 63 and 27% on pellets and 41 and 14% on standard regimens in historical controls. Conclusions: We conclude that estradiol pellets after a single administration provide constant estradiol levels extending into the first trimester of pregnancy, a physiologic estradiol:estrone ratio, and a better endometrial response than standard estrogen regimens. Implantation and pregnancy rates are higher. This approach may be especially suitable for recipients with a poor endometrial response. Presented at the IXth World Congress on In Vitro Fertilization and Assisted Reproduction, Vienna, Austria, April 3, 1995, and the 51st Annual Meeting of the American Society for Reproductive Medicine, Seattle, Washington, October 7–12, 1995.  相似文献   
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BACKGROUND AND PURPOSE: To report local control and follow up outcome data of high precision conformal radiotherapy in childhood brain tumours. MATERIALS AND METHODS: Between December 1999 and December 2002, 26 children (17 boys and 9 girls, median age 11.5 years) with incompletely excised or recurrent benign and low-grade brain tumours [13 craniopharyngiomas, 11 low-grade gliomas (LGG) and 2 others] were treated with three-dimensional (3D) conformal radiotherapy (CRT) (12 patients) and stereotactic conformal radiotherapy (SCRT) (14 patients). Gross tumour volume (GTV) included neuro-imaging based visible tumour and/or resected tumour bed. Clinical target volume (CTV) consisted of GTV+ 5 mm margin and planning target volume (PTV) consisted of additional 5 mm margin for CRT and 2 mm for SCRT. Treatment was delivered with 3-9 conformal fixed fields to a median dose of 54 Gy/30 fractions. RESULTS: The actuarial 2 and 3 year disease free and overall survival was 96 and 100%, respectively (median follow up: 25 months, range 12-47 months). Radiological follow up available in 25 patients revealed complete response in 1, partial regression in 10, stable disease in 13 and progression in 1 patient (within the CTV). One patient with craniopharyngioma on a routine imaging revealed a mild asymptomatic cyst enlargement, which resolved with conservative management. A patient with chiasmatic glioma developed cystic degeneration and hydrocephalus 9 months after SCRT requiring cyst drainage and placement of a ventriculoperitoneal shunt. CONCLUSION: High-precision conformal techniques delivering irradiation to a computer generated target volume employing 7-10 mm 3D margins beyond the visible tumour and/or resected tumour bed appear to be safe in children with incompletely resected or recurrent benign and low-grade brain tumours, based on these data.  相似文献   
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Activation of cell surface death receptors by their cognate ligands triggers apoptosis. Several human death receptors (Fas, TNF-R1, TRAMP, DR4, DR5, DR6, EDA-R and NGF-R) have been identified. The most promising cytokine for anticancer therapy is TRAIL/APO-2L, which induces apoptosis in cancer cells by binding to death receptors TRAIL-R1/DR4 and TRAIL-R2/DR5. The cytotoxic activity of TRAIL is relatively selective to cancer cells compared to normal cells. Signaling by TRAIL and its receptors is tightly regulated process essential for key physiological functions in a variety of organs, as well as the maintenance of immune homeostasis. Despite early promising results, recent studies have identified several TRAIL-resistant cancer cells of various origins. Based on molecular analysis of death-receptor signaling pathways several new approaches have been developed to increase the efficacy of TRAIL. Resistance of cancer cells to TRAIL appears to occur through the modulation of various molecular targets. They may include differential expression of death receptors, constitutively active Akt and NFkappaB, overexpression of cFLIP and IAPs, mutations in Bax and Bak genes, and defects in the release of mitochondrial proteins in resistant cells. Conventional chemotherapeutic and chemopreventive drugs, and irradiation can sensitize TRAIL-resistant cells to undergo apoptosis. Thus, these agents enhance the therapeutic potential of TRAIL in TRAIL-sensitive cells and sensitize TRAIL-resistant cells. TRAIL and TRAIL-receptor antibodies may prove to be useful for cancer therapy, either alone or in association with conventional approaches such as chemotherapy or radiation therapy. This review discusses intracellular mechanisms of TRAIL resistance and various approaches that can be taken to sensitize TRAIL-resistant cancer cells.  相似文献   
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Indian Journal of Pediatrics - To evaluate effect of one year exercise intervention program on bone mineral accrual in children and adolescent with cystic fibrosis (CF). Fifty-two CF children (mean...  相似文献   
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Aim: Gastrointestinal stromal tumor (GIST) is the most common mesenchymal tumor of the gastrointestinal tract. There is limited published data on GIST from the Indian subcontinent. This 5‐year retrospective analysis of 49 patients treated for GIST reports clinical and pathological features and survival outcome by risk stratification. Methods: We reviewed 49 cases of GIST from January 2004 to December 2008. Imatinib was administered after surgery in patients with either high‐risk, residual or metastatic disease and at onset of recurrence or metastatic disease in patients with intermediate risk. Results: The mean age was 50 years (range, 17–80 years). Patients with localized tumor were classified as low (n = 2), intermediate (n = 4) and high risk (n = 32), based on the primary tumor and mitotic index. At a median follow up of 21 months, 2‐year and 3‐year recurrence or progression‐free survival rates were 61 and 39%, respectively, for all patients. The median recurrence‐free survival rate in the intermediate‐risk and high‐risk groups were 7 and 49 months, respectively. The median progression‐free survival in the residual (n = 4) and metastatic disease group (n = 7) was 10 and 29 months, respectively. Conclusion: This study demonstrates the role of imatinib in adjuvant and therapeutic settings. Responses have been durable and most patients tolerate the drug well at clinically effective doses. In view of high recurrence rates in the intermediate‐risk group in our study, it would be better to keep these patients on strict follow up to detect recurrence at the earliest opportunity.  相似文献   
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