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41.
Amanda M. Midboe A. Rani Elwy Janet M. Durfee Allen L. Gifford Vera Yakovchenko Richard A. Martinello David Ross Maggie Czarnogorski Matthew B. Goetz Steven M. Asch 《Journal of general internal medicine》2014,29(4):831-834
We are in a new era of partner-based implementation research, and we need clear strategies for how to navigate this new era. Drawing on principles from community-based participatory research, the Clinical Public Health group of the Department of Veterans Affairs and the HIV/Hepatitis Quality Enhancement Research Initiative (HHQUERI) forged a longstanding partnership that has improved the care of Veterans with Human Immunodeficiency Virus (HIV) and Hepatitis C Virus. An exemplar HIV testing project epitomizes this partnership and is discussed in terms of the lessons learned as a result of our high level of collaboration around design, analysis, implementation, and dissemination across projects over the past several years. Lessons learned through this partnered testing program involve respecting different time horizons among the partners, identifying relevant research questions for both parties, designing flexible studies, engaging all partners throughout the research, and placing an emphasis on relationship building at all times. These lessons and strategies can benefit others conducting partner-based research both within the Veterans Health Administration (VA) and in other integrated healthcare systems. 相似文献
42.
Spread of X inactivation on chromosome 15 is associated with a more severe phenotype in a girl with an unbalanced t(X; 15) translocation
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43.
B-cell growth factor receptor expression and B-cell growth factor response of leukemic B cell precursors and B lineage lymphoid progenitor cells 总被引:8,自引:1,他引:8
Uckun FM; Fauci AS; Heerema NA; Song CW; Mehta SR; Gajl-Peczalska K; Chandan M; Ambrus JL 《Blood》1987,70(4):1020-1034
The purpose of this study was to analyze the expression of B cell growth factor (BCGF) receptors and to elucidate the biologic effects of biochemically purified natural BCGF at the B cell precursor stage of human B lineage lymphoid differentiation. The specific binding of radioiodinated high-mol-wt BCGF (125I-HMW-BCGF) and low-molecular-wt BCGF (125I-LMW-BCGF) to fresh marrow blasts from B cell precursor acute lymphoblastic leukemia (ALL) patients was initially investigated. The estimated number of radioiodinated BCGF molecules bound per blast ranged from undetectable to 24.3 X 10(3) for HMW-BCGF, and from 11.5 X 10(3) to 457.8 X 10(3) for LMW-BCGF. In 3H-TdR incorporation assays, 75% of cases showed a significant response to LMW-BCGF with a median stimulation index of 9.3. By comparison, only 33% of cases showed a significant response to HMW-BCGF with a median stimulation index of 2.4. Subsequently, B cell precursor colony assays were performed to assess and compare the biologic effects of BCGF on leukemic B lineage lymphoid progenitor cells. Among 28 cases studied, 57% responded to both HMW-BCGF and LMW-BCGF, 21% responded only to LMW-BCGF, and the remaining cases showed no proliferative response to either growth factor. The response patterns of virtually pure populations of FACS- sorted leukemic B cell precursors were essentially identical to the proliferative responses of unsorted leukemic B-cell precursors. Synergistic effects between HMW-BCGF and LMW-BCGF were observed in 80% of the cases that responded to both. The numbers of cell-bound radioiodinated BCGF molecules, the stimulation indices, as well as the number of B cell precursor colonies in BCGF-stimulated cultures showed a marked interpatient variation. Patients with structural chromosomal abnormalities (SCAs) involving 12p11-13 or patients with a Philadelphia chromosome showed a greater HMW-BCGF response at the level of leukemic progenitor cells than did other patients (P = .02). The LMW-BCGF response was significantly greater for patients with SCA than for patients without SCA (P = .04). The response of leukemic progenitor cells to HMW-BCGF or LMW-BCGF did not correlate with sex, age, disease status, FAB morphology, WBC at diagnosis, or immunophenotype. To our knowledge, this study represents the first detailed analyses of BCGF receptor expression and BCGF effects in B cell precursor ALL. The data presented provide direct evidence for the expression of functional receptors for both HMW-BCGF and LMW-BCGF in B cell precursor ALL. 相似文献
44.
The use of 7-amino actinomycin D in identifying apoptosis: simplicity of use and broad spectrum of application compared with other techniques 总被引:9,自引:5,他引:9
Philpott NJ; Turner AJ; Scopes J; Westby M; Marsh JC; Gordon-Smith EC; Dalgleish AG; Gibson FM 《Blood》1996,87(6):2244-2251
The detection and quantitation of apoptotic cells is becoming increasingly important in the investigation of the role of apoptosis in cellular proliferation and differentiation. The pathogenesis of hematologic disorders such as aplastic anemia and the development of neoplasia are believed to involve dysregulation of apoptosis. To quantitate accurately the proportion of apoptosis cells within different cell types of a heterogeneous cell population such as blood or bone marrow, a method is required that combines the analysis of large numbers of cells with concurrent immunophenotyping of cell surface antigens. In this study, we have evaluated such a method using the fluorescent DNA binding agent, 7-amino actinomycin D (7AAD), to stain three diverse human cell lines, induced to undergo apoptosis by three different stimuli. Flow cytometric analysis defines three populations on the basis of 7AAD fluorescence and forward light scatter. We have shown by cell sorting and subsequent morphological assessment and terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick end labeling that the populations defined by 7AAD represent live, apoptotic, and late-apoptotic/dead cells. This method is quick, simple, reproducible, and cheap and will be a valuable tool in the investigation of the role of apoptosis in normal physiology and in disease states. 相似文献
45.
Karl A. Lorenz MD MSHS Sydney M. Dy MD MPH Arash Naeim MD PhD Anne M. Walling MD Homayoon Sanati MD Patricia Smith MS Roberta Shanman MS Carol P. Roth RN MPH Steven M. Asch MD MPH 《Journal of pain and symptom management》2009,37(6):943-964
Patients and physicians often cite symptom control as one of their most important goals in cancer care. Despite this, a previous systematic review found few tools for evaluating the quality of supportive cancer management. We developed a comprehensive set of quality indicators for evaluating pain and nonpain symptom management as well as care planning needs in cancer patients. Based on the prevalence and quality-of-life data, clinician-researchers prioritized pain, psychosocial distress, dyspnea, nausea and vomiting, fatigue and anorexia, treatment-associated toxicities, and information and care planning for quality-indicator development. Using search terms and selection criteria, we identified English-language documents from Medline (1997–2007) and Internet-based searches. Based on this evidence, clinician-reviewers proposed process quality indicators. We then used the VA Health Services Research and Development (VA HSR & D) appropriateness methods to compile the ratings of a multidisciplinary, international expert panel of the validity and feasibility of each indicator. The panel judged 92 out of 133 (69%) proposed quality indicators valid and feasible (15 out of 23 pain, 5 out of 6 depression, 8 out of 11 dyspnea, 15 out of 19 nausea and vomiting, 13 out of 26 fatigue and anorexia, 23 out of 32 other treatment-associated toxicities, and 13 out of 16 information and care planning). Of the final indicators, 67 are potentially useful for inpatient and 81 for outpatient evaluation, and 26 address screening, 12 diagnostic evaluation, 20 management, and 21 follow-up. These quality indicators provide evidence-explicit tools for measuring processes critical to ensuring high-quality supportive cancer care. Research is needed to characterize adherence to recommended practices and to evaluate the use of these measures in quality improvement efforts. 相似文献
46.
L B Dain P Stein A R Krimer R H Asch E P de Fried E H Charreau M Tesone 《Fertility and sterility》1991,55(6):1093-1098
STUDY OBJECTIVE: To examine the progesterone (P) production by cultured granulosa cells and the hormonal content in the follicular fluid (FF) of ovarian-hyperstimulated women. DESIGN: Retrospective. SETTING: Private Fertility Clinic and National Research Institute. PATIENTS: Eighteen patients undergoing in vitro fertilization or gamete intrafallopian transfer programs. RESULTS: Progesterone levels Measured in the culture medium of granulosa cells decreased sixfold with culture time. Human luteinizing hormone (LH) increased P production only when basal P production was less than 1 microgram/mL. Granulosa cell P production in culture was negatively correlated with FF LH-human chorionic gonadotropin (hCG) levels. Follicular fluid follicle-stimulating hormone (FSH) levels were positively correlated with FF P and 17 beta-estradiol (E2) concentrations. Similar results were found between FF LH (hCG) and E2 levels, but there was no relationship between FF LH (hCG) and FF P values. CONCLUSION: The high dose of hCG administered during gonadotropin treatment could induce a decrease in the in vitro granulosa cell P production. 相似文献
47.
Kaplan Carolyn R. Olive David L. Sabella Vincente Asch Ricardo H. Balmaceda Jose P. Riehl Robert M. Groff Terry R. Burns William N. Schenken Robert S. 《Journal of assisted reproduction and genetics》1989,6(5):298-304
Superovulation with intrauterine insemination (SO-IUI) has been suggested as an alternative to gamete intrafallopian transfer (GIFT), despite the absence of controlled or comparative trials. We retrospectively analyzed all GIFT and SO-IUI cycles performed concurrently from January 1985 to August of 1987 at a single university center. Pregnancy rates were significantly better for GIFT than SO-IUI (P<0.001), with an odds ratio of 3.25 (P=0.001). Stepwise multiple logistic regression identifield factors that correlate with pregnancy: absence of endometriosis (P=0.05), infertility<3 years' duration (P=0.002), TMS 30×106 (P=0.005), and treatment with GIFT rather than SO-IUI (P=0.001). These data give a first approximation of the increased efficacy of GIFT versus SO-IUI and provide valuable insight into significant confounding variables to be considered when planning a randomized, prospective trial to evaluate these techniques. 相似文献
48.
F J Rojas A T La T Ord P Patrizio J P Balmaceda S J Silber R H Asch 《Fertility and sterility》1992,58(5):1000-1005
OBJECTIVES: To assess the ability of sperm aspirated from the epididymis of men with congenital absence of the vas deferens to penetrate zona-free hamster oocytes. To directly compare the performance of human epididymal sperm in the zona-free hamster oocyte sperm penetration assay (SPA) with the results of human in vitro fertilization (IVF). DESIGN: Sperm penetration assay was carried out with epididymal sperm retrieved microsurgically, and with ejaculated sperm obtained from fertile donors (internal controls). For direct comparison, SPA was performed with the same epididymal sperm sample used for IVF. PATIENTS, PARTICIPANTS: Men with congenital absence of the vas deferens undergoing sperm aspiration as part of their infertility treatment and control donors who provided ejaculated sperm. RESULTS: Epididymal sperm penetrated SPA with a score of 0% to 30%. The SPA scores for internal controls using ejaculated sperm was 30% to 71%. Linear regression analysis of the association between penetration scores in SPA and fertilization rate in IVF indicated a positive correlation that was highly significative. CONCLUSIONS: These findings using SPA confirm previous reports on the fertilizing potential of human epididymal sperm and its ability to produce normal pregnancies. The good correlation between SPA and human IVF using epididymal sperm suggest that SPA is an excellent bioassay to test laboratory experimental conditions for improving fertilizing capacity of human epididymal sperm. 相似文献
49.
Results of tubal embryo transfer in premature ovarian failure 总被引:1,自引:0,他引:1
D A Rotsztejn J Remohi L N Weckstein T Ord D L Moyer J P Balmaceda R H Asch 《Fertility and sterility》1990,54(2):348-350
The transfer of embryos generated in vitro to the fallopian tubes in 11 cases of premature ovarian failure resulted in 9 clinical pregnancies. This approach may have theoretical advantages over GIFT and IVF-ET in agonadal patients. 相似文献
50.
Force generated by human sperm correlated to velocity and determined using a laser generated optical trap 总被引:3,自引:0,他引:3
The development of the single beam gradient force optical trap has made it possible to manipulate cells solely by laser light. A continuous wave Nd:YAG (1.06 microns) laser beam was directed into a conventional microscope and focused onto the viewing plane by the objective lens. The laser beam power at which human sperm were released from the trap was measured and correlated to the sperm's linear velocity before trapping. The mean trapping power readings for slow, medium, and fast motile sperm were 57, 73, and 84 mW, respectively. The analysis of measurements over the total population demonstrated that zig-zag motile sperm had significantly higher mean power readings when compared with straight motile sperm with similar mean linear velocities. In two cases, specimens required significantly less trapping power when the measurements were repeated 24 hours later. 相似文献