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91.
The levels of protooncogene RNA in matched bone marrow and peripheral blood cells obtained from patients with newly diagnosed acute myelogenous leukemia were compared. While the absolute amounts of c-myc RNA in the matched specimens are similar, the levels are not correlated. In contrast, while the levels of c-fos RNA in the matched bone marrow and peripheral blood cells are correlated, the absolute levels of c-fos RNA differ substantially. The level of histone H3 RNA is higher in bone marrow cells than in peripheral blood cells. These substantial differences in protooncogene RNA levels between leukemic cells found in the bone marrow and in the peripheral blood make it impossible to accurately "characterize" gene expression in leukemic cells if studies are restricted to the cells in either compartment. Additionally, there appears to be a significant relationship between the levels of c-fos RNA and triose phosphate isomerase RNA and the height of the white blood cell count and between the level of c-fos RNA in marrow cells and the proportion of monocytic cells present. 相似文献
92.
Anderson Madison D. Merkin Sharon Stein Everson-Rose Susan A. Widome Rachel Seeman Teresa Magnani Jared W. Rodriguez Carlos J. Lutsey Pamela L. 《Journal of immigrant and minority health / Center for Minority Public Health》2021,23(4):668-668
Journal of Immigrant and Minority Health - The original version of this article unfortunately contained a typo in co-author name. 相似文献
93.
Sarah Duncan-Park Claire Dunphy Jacqueline Becker Christine D’Urso Rachel Annunziato Joshua Blatter Carol Conrad Samuel B. Goldfarb Don Hayes Jr. Ernestina Melicoff Marc Schecter Gary Visner Brian Armstrong Hyunsook Chin Karen Kesler Nikki M. Williams Jonah N. Odim Stuart C. Sweet Lara Danziger-Isakov Eyal Shemesh 《American journal of transplantation》2021,21(9):3112-3122
Remote interventions are increasingly used in transplant medicine but have rarely been rigorously evaluated. We investigated a remote intervention targeting immunosuppressant management in pediatric lung transplant recipients. Patients were recruited from a larger multisite trial if they had a Medication Level Variability Index (MLVI) ≥2.0, indicating worrisome tacrolimus level fluctuation. The manualized intervention included three weekly phone calls and regular follow-up calls. A comparison group included patients who met enrollment criteria after the subprotocol ended. Outcomes were defined before the intent-to-treat analysis. Feasibility was defined as ≥50% of participants completing the weekly calls. MLVI was compared pre- and 180 days postenrollment and between intervention and comparison groups. Of 18 eligible patients, 15 enrolled. Seven additional patients served as the comparison. Seventy-five percent of participants completed ≥3 weekly calls; average time on protocol was 257.7 days. Average intervention group MLVI was significantly lower (indicating improved blood level stability) at 180 days postenrollment (2.9 ± 1.29) compared with pre-enrollment (4.6 ± 2.10), p = .02. At 180 days, MLVI decreased by 1.6 points in the intervention group but increased by 0.6 in the comparison group (p = .054). Participants successfully engaged in a long-term remote intervention, and their medication blood levels stabilized. NCT02266888. 相似文献
94.
Selective stimulation of cat sciatic nerve using an array of varying-length microelectrodes 总被引:7,自引:0,他引:7
Restoration of motor function to individuals who have had spinal cord injuries or stroke has been hampered by the lack of an interface to the peripheral nervous system. A suitable interface should provide selective stimulation of a large number of individual muscle groups with graded recruitment of force. We have developed a new neural interface, the Utah Slanted Electrode Array (USEA), that was designed to be implanted into peripheral nerves. Its goal is to provide such an interface that could be useful in rehabilitation as well as neuroscience applications. In this study, the stimulation capabilities of the USEA were evaluated in acute experiments in cat sciatic nerve. The recruitment properties and the selectivity of stimulation were examined by determining the target muscles excited by stimulation via each of the 100 electrodes in the array and using force transducers to record the force produced in these muscles. It is shown in the results that groups of up to 15 electrodes were inserted into individual fascicles. Stimulation slightly above threshold was selective to one muscle group for most individual electrodes. At higher currents, co-activation of agonist but not antagonist muscles was observed in some instances. Recruitment curves for the electrode array were broader with twitch thresholds starting at much lower currents than for cuff electrodes. In these experiments, it is also shown that certain combinations of electrode pairs, inserted into an individual fascicle, excite fiber populations with substantial overlap, whereas other pairs appear to address independent populations. We conclude that the USEA permits more selective stimulation at much lower current intensities with more graded recruitment of individual muscles than is achieved by conventional cuff electrodes. 相似文献
95.
96.
Rota GC Stein JA 《Proceedings of the National Academy of Sciences of the United States of America》1990,87(23):9250-9254
It is shown that the Hopf algebra dual of a supersymmetric Hopf algebra admits two presentations, and a natural isomorphism between them is described. 相似文献
97.
S C Younger D C Clark R Oehmig-Lindroth R J Stein 《Journal of the American Geriatrics Society》1990,38(11):1169-1175
Psychological autopsy methodology has not been applied in studies of elderly suicides, despite the fact that the elderly are associated with a higher rate of suicide than any other age group. One school of thought argues that older adults who die by suicide are socially isolated and/or estranged for a long period of time before death, so that knowledgeable informants are difficult or impossible to obtain. In the present retrospective study we examine the number and availability of knowledgeable informants for 145 older people who committed suicide. We believe that the ability to access several motivated informants per case is essential to any psychological autopsy study by modern standards. The stereotype of the "average expectable" elderly suicide victim as socially isolated and living alone or in an institutional setting was not supported by our findings; an unexpectedly high percentage of subjects were married at the time of their death. There was at least one knowledgeable informant in 90% of cases and two or more in almost 50%. In 46%, the subject had expressed despondency over illness. In a prospective study involving interviews with informants for eight subjects, all eight had at least two knowledgeable and willing informants. Two cases of the eight are presented to illustrate the role of delirium and an ominous diagnosis (cancer) as causes of suicide. We conclude that it is feasible to do a psychological autopsy study of elderly suicides. 相似文献
98.
Glazer HR Stein DS Schafer DS 《Journal of healthcare education and training : the journal of the American Society for Healthcare Education and Training / American Hospital Association》1993,8(1):8-11
Preparing for the health care system of the future includes the ability to abstract information from relevant sectors of the environment. This study looked at the way health care educators scan the environment and the relationship of scanning behavior to management style. Results indicate that education and training professionals focus on the regulatory and customer sectors of the environment more than the technological and sociopolitical sectors. 相似文献
99.
100.
Large-cell lymphomas: clinical and prognostic features 总被引:1,自引:0,他引:1
R S Stein J P Greer J M Flexner J D Hainsworth R D Collins W R Macon J B Cousar 《Journal of clinical oncology》1990,8(8):1370-1379
We reviewed the clinical and pathologic features in 186 patients with large-cell lymphomas seen at Vanderbilt University Hospital between 1970 and 1986. Ninety-two cases (49%) were large noncleaved-cell lymphoma (LNCCL), 61 cases (33%) were large-cleaved-cell lymphoma (LCCL), 17 cases (9%) were peripheral T-cell lymphoma (PTCL), and 16 cases (9%) were immunoblastic sarcoma of B cells (IBS-B). These subsets of large-cell lymphoma did not differ with respect to median age, distribution by stage, or incidence of bone marrow involvement. Significant differences between groups were noted with regard to male:female ratio, incidence of symptoms, incidence of extranodal disease, and pattern of adenopathy. However, when LCCL was excluded from the analysis, none of these differences were significant. By univariate analysis, age, stage, marrow involvement, extranodal disease, B symptoms, elevated serum lactic dehydrogenase (LDH), and diffuse pattern were unfavorable prognostic features in large-cell lymphoma. However, when cases were stratified by cell of origin, nodular versus diffuse pattern was of no prognostic significance. Nodularity was favorable only because 71% of nodular and nodular-diffuse cases were LCCL, while the majority of diffuse cases were LNCCL. Although IBS-B is considered a "high-grade" lymphoma, we found no evidence for inferior survival in these patients compared with LNCCL or LCCL. In fact, survival was better in IBS-B than in LNCCL or LCCL, although this difference was not significant. However, survival was significantly inferior in PTCL (median, 11 months) compared with the other subsets of large-cell lymphoma (median, 46 months; P = .038, log-rank test). Since the association of PTCL and an inferior survival has most often been noted in the context of "second-generation" chemotherapy, we believe that this association may be therapy-dependent and may be minimized by the use of more aggressive chemotherapy regimens. 相似文献