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601.
Recombinant human granulocyte-macrophage (GM) colony-stimulating factor (GM-CSF), G-CSF, and interleukin-3 (IL-3) labeled with 125I were used to study the characteristics and distribution of receptors for these factors on in vitro cell lines and on cells from patients with acute nonlymphocytic leukemia (ANL) and acute lymphocytic leukemia (ALL). Receptors for GM-CSF and G-CSF were restricted to a subset of myelomonocytic cell lines whereas IL-3 receptors were also found on pre- B- or early B-cell lines. Receptors for all three CSFs were broadly distributed on ANL cells, with considerable variability in levels of expression. Measurement of the colony-forming ability of ANL cells in response to the CSFs showed that there was no direct correlation between the ability of the cells to respond to a growth factor and the absolute number of receptors expressed for that growth factor. Binding of radiolabeled IL-3 and GM-CSF to ANL cells produced complex biphasic curves. Further analysis showed that both IL-3 and GM-CSF were able to partially compete for specific binding of the heterologous radiolabeled ligand to cells from several ANL patients, suggesting that heterogeneity may exist in human CSF receptors. These results provide new insights into the complex role that CSFs may play in ANL.  相似文献   
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The Delphi panel technique was tested as a component of a healthinformation system in 1991 in rural Kenya. Twenty-six panelmembers were selected from twelve villages in a sub-districtwith a population of 160000. Most of the panelists had poorreading and writing skills, so twelve interviewers were trainedto assist them in completing questionnaires on issues such ascommon illnesses in different age-groups and on priority interventions.Except for minor differences in the ranking of common illnesses,the Delphi study provided results consistent with a householdinterview survey simultaneously undertaken in the area. Theusefulness of Delphi panel studies in African health informationsystems and their costs when conducted by local staff are discussed.  相似文献   
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A phase 1 study was conducted using a monoclonal antimelanoma antibody-DTPA conjugate labeled with indium-111, for immunolymphoscintigraphy in patients with metastatic melanoma. The imaging agent, labeled with 1 mCi (37 MBq) In-111, was administered as an interstitial interdigital injection to six patients scheduled to undergo lymph node dissection for suspected metastatic malignant melanoma. No adverse effects were observed in any of the patients either during or after the infusion as determined by clinical and laboratory parameters. Antibodies to the murine immunoglobulin were produced in some patients. Regional lymph nodes were visualized whether tumor-bearing or not, and light microscopic autoradiography showed In-111 activity associated with histiocytes. One of two patients harboring both tumor-bearing and tumor-free lymph nodes exhibited preferential localization in tumor-bearing nodes. The authors conclude that this study demonstrates safety of the radiopharmaceutical and that further study is needed to improve its usefulness for diagnosis of lymph node metastases.  相似文献   
609.

Introduction

Androgens have been hypothesised to influence risk of breast cancer through several possible mechanisms, including their conversion to estradiol or their binding to the oestrogen receptor and/or androgen receptor (AR) in the breast. Here, we report on the results of a large and comprehensive study of the association between genetic variation in the AR gene and risk of breast cancer in the National Cancer Institute Breast and Prostate Cancer Cohort Consortium (BPC3).

Methods

The underlying genetic variation was determined by first sequencing the coding regions of the AR gene in a panel of 95 advanced breast cancer cases. Second, a dense set of markers from the public database was genotyped in a panel of 349 healthy women. The linkage disequilibrium relationships (blocks) across the gene were then identified, and haplotype-tagging single nucleotide polymorphisms (htSNPs) were selected to capture the common genetic variation across the locus. The htSNPs were then genotyped in the nested breast cancer cases and controls from the Cancer Prevention Study II, European Prospective Investigation into Cancer and Nutrition, Multiethnic Cohort, Nurses' Health Study, and Women's Health Study cohorts (5,603 breast cancer cases and 7,480 controls).

Results

We found no association between any genetic variation (SNP, haplotype, or the exon 1 CAG repeat) in the AR gene and risk of breast cancer, nor were any statistical interactions with known breast cancer risk factors observed.

Conclusion

Among postmenopausal Caucasian women, common variants of the AR gene are not associated with risk of breast cancer.  相似文献   
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Diagnostic imaging of mesenteric infarction   总被引:15,自引:0,他引:15  
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