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71.
During this time of nursing shortages, hospitals that want to maintain the competitive edge must seek ways to recruit and retain a competent nursing staff. This study was conducted in a large hospital that strives to be the primary health care provider and employer of choice in its geographic region. The purpose of the study was to assess new nurses' perceptions of nursing practice and their expectations for meeting professional goals. Sixty-seven new nurses from 13 hospital departments were interviewed. Comprehensive orientation, continuing education, and mentoring were important values identified by this group of nurses. Communication with physicians and fear of causing accidental harm to patients were expressed concerns. Data from this survey will be used by the organization to change orientation policies to better meet the needs of the nursing staff and improve recruitment and retention of nurses. 相似文献
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Prenatal identification of potential donors for umbilical cord blood transplantation for Fanconi anemia 总被引:1,自引:0,他引:1
AD Auerbach ; Q Liu ; R Ghosh ; MS Pollack ; GW Douglas ; HE Broxmeyer 《Transfusion》1990,30(8):682-687
Reported here are studies of Fanconi anemia fetal cells that led to the first use of umbilical cord blood for hematopoietic reconstitution in a clinical trial. Prenatal diagnosis and HLA typing were performed in fetuses at risk for Fanconi anemia (FA) to identify, prior to birth, those that were unaffected with the syndrome and were HLA-identical to affected siblings. Umbilical cord blood was harvested at the delivery of these infants; assays of progenitor cells indicated the presence of colony-forming units-granulocyte-macrophage (CFU-GM) in numbers similar to those of bone marrow CFU-GM that are associated with successful engraftment in HLA-matched allogeneic bone marrow transplantation. The possibility that umbilical cord blood from a single individual can be used as an alternative to bone marrow for hematopoietic reconstitution has now been demonstrated by the successful engraftment of two patients with FA. Progenitor cell assays of umbilical cord blood collected at the birth of a child affected with FA, who had been misdiagnosed on the basis of chorionic villus sampling (CVS) studies, indicated a profound deficiency in colony formation, consistent with previously reported abnormalities in the growth of FA cells in vitro. These results suggest that the hematopoietic disorder in FA is related to an underlying problem with cell proliferation. 相似文献
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Ellen C. Caniglia James M. Robins Lauren E. Cain Caroline Sabin Roger Logan Sophie Abgrall Michael J. Mugavero Sonia Hernández-Díaz Laurence Meyer Remonie Seng Daniel R. Drozd George R. Seage III Fabrice Bonnet Fabien Le Marec Richard D. Moore Peter Reiss Ard van Sighem William C. Mathews Inma Jarrín Belén Alejos Steven G. Deeks Roberto Muga Stephen L. Boswell Elena Ferrer Joseph J. Eron John Gill Antonio Pacheco Beatriz Grinsztejn Sonia Napravnik Sophie Jose Andrew Phillips Amy Justice Janet Tate Heiner C. Bucher Matthias Egger Hansjakob Furrer Jose M. Miro Jordi Casabona Kholoud Porter Giota Touloumi Heidi Crane Dominique Costagliola Michael Saag Miguel A. Hernán 《Statistics in medicine》2019,38(13):2428-2446
Decisions about when to start or switch a therapy often depend on the frequency with which individuals are monitored or tested. For example, the optimal time to switch antiretroviral therapy depends on the frequency with which HIV-positive individuals have HIV RNA measured. This paper describes an approach to use observational data for the comparison of joint monitoring and treatment strategies and applies the method to a clinically relevant question in HIV research: when can monitoring frequency be decreased and when should individuals switch from a first-line treatment regimen to a new regimen? We outline the target trial that would compare the dynamic strategies of interest and then describe how to emulate it using data from HIV-positive individuals included in the HIV-CAUSAL Collaboration and the Centers for AIDS Research Network of Integrated Clinical Systems. When, as in our example, few individuals follow the dynamic strategies of interest over long periods of follow-up, we describe how to leverage an additional assumption: no direct effect of monitoring on the outcome of interest. We compare our results with and without the “no direct effect” assumption. We found little differences on survival and AIDS-free survival between strategies where monitoring frequency was decreased at a CD4 threshold of 350 cells/μl compared with 500 cells/μl and where treatment was switched at an HIV-RNA threshold of 1000 copies/ml compared with 200 copies/ml. The “no direct effect” assumption resulted in efficiency improvements for the risk difference estimates ranging from an 7- to 53-fold increase in the effective sample size. 相似文献
76.
Monoclonal antibodies are increasingly being developed to treat multiple disease areas, including those related to oncology, immunology, neurology, and ophthalmology. There are multiple factors, such as charge, size, neonatal Fc receptor (FcRn) binding affinity, target affinity and biology, immunoglobulin G (IgG) subclass, degree and type of glycosylation, injection route, and injection site, that could affect the pharmacokinetics (PK) of these large macromolecular therapeutics, which in turn could have ramifications on their efficacy and safety. This minireview examines how characteristics of the antibodies could be altered to change their PK profiles. For example, it was observed that a net charge modification of at least a 1-unit shift in isoelectric point altered antibody clearance. Antibodies with enhanced affinity for FcRn at pH 6.0 display longer serum half-lives and slower clearances than wild type. Antibody fragments have different clearance rates and tissue distribution profiles than full length antibodies. Fc glycosylation is perceived to have a minimal effect on PK while that of terminal high mannose remains unclear. More investigation is warranted to determine if injection route and/or site impacts PK. Nonetheless, a better understanding of the effects of all these variations may allow for the better design of antibody therapeutics. 相似文献
77.
CD4(+) T cells expressing the latent form of transforming growth factor-β [latency-associated peptide (LAP) (TGF-β(1))] play an important role in the modulation of immune responses. Here, we identified a novel peptide ligand (GPC(81-95) ) with an intrinsic ability to induce membrane-bound LAP (TGF-β(1)) expression on a subpopulation of human CD4(+) T cells (using flow cytometry; ranging from 0·8% to 2·6%) and stimulate peripheral blood mononuclear cells to release LAP (TGF-β(1) ) (using ELISPOT assay; ranging from 0·03% to 0·16%). In spite of this low percentage of responding cells, GPC(81-95) significantly reduced Toll-like receptor 4 ligand-induced tumour necrosis factor-α production in a TGF-β(1) - and CD4(+) T-cell-dependent manner. The results demonstrate that GPC(81-95) is a useful tool to study the functional properties of a subpopulation of LAP (TGF-β(1))(+) CD4(+) T cells and suggest a pathway that can be exploited to suppress inflammatory response. 相似文献
78.
Mali RS Ramdas B Ma P Shi J Munugalavadla V Sims E Wei L Vemula S Nabinger SC Goodwin CB Chan RJ Traina F Visconte V Tiu RV Lewis TA Stern AM Wen Q Crispino JD Boswell HS Kapur R 《Cancer cell》2011,20(3):357-369
We show constitutive activation of Rho kinase (ROCK) in cells bearing oncogenic forms of KIT, FLT3, and BCR-ABL, which is dependent on PI3K and Rho GTPase. Genetic or pharmacologic inhibition of ROCK in oncogene-bearing cells impaired their growth as well as the growth of acute myeloid leukemia patient-derived blasts and prolonged the life span of mice bearing myeloproliferative disease. Downstream from ROCK, rapid dephosphorylation or loss of expression of myosin light chain resulted in enhanced apoptosis, reduced growth, and loss of actin polymerization in oncogene-bearing cells leading to significantly prolonged life span of leukemic mice. In summary we describe a pathway involving PI3K/Rho/ROCK/MLC that may contribute to myeloproliferative disease and/or acute myeloid leukemia in humans. 相似文献
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80.
Laxmaiah Manchikanti Vidyasagar Pampati Ramsin M. Benyamin Mark V. Boswell 《International journal of medical sciences》2015,12(3):214-222
Study Design: Comparative assessment of randomized controlled trials of caudal and lumbar interlaminar epidural injections in chronic lumbar discogenic pain.Objective: To assess the comparative efficacy of caudal and lumbar interlaminar approaches of epidural injections in managing axial or discogenic low back pain.Summary of Background Data: Epidural injections are commonly performed utilizing either a caudal or lumbar interlaminar approach to treat chronic lumbar axial or discogenic pain, which is pain exclusive of that associated with a herniated intervertebral disc, or that is due to degeneration of the zygapophyseal joints, or due to dysfunction of the sacroiliac joints, respectively. The literature on the efficacy of epidural injections in managing chronic axial lumbar pain of presumed discogenic origin is limited.Methods: The present analysis is based on 2 randomized controlled trials of chronic axial low back pain not caused by disc herniation, radiculitis, or facet joint pain, utilizing either a caudal or lumbar interlaminar approach, with a total of 240 patients studied, and a 24-month follow-up. Patients were assigned to receive either local anesthetic only or local anesthetic with a steroid in each 60 patient group.Results: The primary outcome measure was significant improvement, defined as pain relief and functional status improvement of at least 50% from baseline, which was reported at 24-month follow-ups in 72% who received local anesthetic only with a lumbar interlaminar approach and 54% who received local anesthetic only with a caudal approach. In patients receiving local anesthetic with a steroid, the response rate was 67% for those who had a lumbar interlaminar approach and 68% for those who had a caudal approach at 12 months. The response was significantly better in the lumbar interlaminar group who received local anesthetic only, 77% versus 56% at 12 months and 72% versus 54% at 24 months.Conclusion: This assessment shows that in patients with axial or discogenic pain in the lumbar spine after excluding facet joint and SI Joint pain, epidural injections of local anesthetic by the caudal or lumbar interlaminar approach may be effective in managing chronic low back pain with a potential superiority for a lumbar interlaminar approach over a caudal approach. 相似文献