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排序方式: 共有196条查询结果,搜索用时 15 毫秒
81.
In today’s world in which there is a surplus of both scientists and online nutrition “experts,” how do young professionals establish themselves? Becoming established as an expert requires selling yourself and your ideas to your colleagues and the general public by using effective communication skills. Helping young professionals develop these skills was the goal of a panel held at the ASN Scientific Sessions and Annual Meeting at Experimental Biology 2015. This panel featured a set of distinguished speakers who discussed techniques and strategies to enhance professional reputations centered around effectively leveraging communication platforms and opportunities to engage with colleagues. Early-career nutrition scientists can use the guidance provided by the panelists to improve their visibility and be a champion for themselves in order to establish themselves as experts in the field.  相似文献   
82.
Individual monoclonal antibodies to human IgG have been shown to form immune complexes of defined stoichimetry. These complexes are non-precipitating and do not exhibit turbidity. Combinations of two monoclonal antibodies directed against spatially distinct antigenic determinants produce complexes exhibiting marked turbidity. Such combined monoclonal antibody ‘cocktails’ may be applied to quantitative techniques.  相似文献   
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Quality assessment of randomized controlled trials of contrast media   总被引:1,自引:0,他引:1  
Powe  NR; Kinnison  ML; Steinberg  EP 《Radiology》1989,170(2):377-380
Numerous randomized controlled trials (RCTs) have been conducted to define the relative benefits of low-osmolality contrast media (LOM) and high-osmolality contrast media (HOM). Because of the clinical and economic significance of the conclusions drawn from these RCTs, the authors used a standardized instrument to evaluate the quality of study design and data analysis of 100 RCTs published between 1982 and 1987 that compared LOM and HOM. The mean quality score (+/- standard deviation) was 39 +/- 12 (maximum possible score, 100). The largest number of patients studied in any RCT was 435; the smallest was five. A majority of the RCTs received high scores on three attributes of quality, intermediate scores on seven, and low scores on nine. These results underscore the difficulty of designing, performing, analyzing, and reporting high-quality RCTs. Nevertheless, limitations in study design and data analysis need to be considered when interpreting results of these RCTs. Future RCTs comparing LOM and HOM should be performed with greater attention to basic elements of good study design and data analysis.  相似文献   
85.
The Survival Motor Neuron (SMN) gene shows deletions in the majority of patients with Spinal Muscular Atrophy (SMA), a disease of motor neuron degeneration. To date only two missense mutations have been reported in SMN in patients with SMA. The fact that no SMN-homologues have been forthcoming from data-base searching has resulted in a lack of hypotheses concerning the structural and functional consequences of these mutations. Recently SMN has been shown to interact with heterogeneous nuclear ribonucleoproteins (hnRNPs) suggesting a role in mRNA metabolism. We describe a novel missense mutation and the subsequent identification of a triplicated tyrosine-glycine (Y-G) peptide sequence at the C-terminal of SMN which encompasses each of the three predicted amino acid sequence substitutions. We have identified apparent orthologues of SMN in Caenorhabditis elegans and Schizosaccharomyces pombe. These sequences retain the highly conserved Y-G motif and provide additional support for a role of SMN in mRNA metabolism.   相似文献   
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87.
Objective: (1) To evaluate a clinical guideline for the diagnostic investigation of patients presenting with signs and symptoms (present for longer than 6 weeks) suggesting a chronic polyneuropathy. (2) To investigate the contribution of electrophysiological studies to a focused search for aetiology in these patients. Methods: A chart review was carried out of a consecutive group of outpatients in 1993-7 at a university department of neurology, with signs and symptoms suggesting a polyneuropathy in whom the diagnostic investigation had been carried out according to a recently introduced guideline. Diagnostic tests were performed and final diagnoses were made. Results: Unnecessary investigations were carried out in 108 (51%) of 213 patients and too few tests in 23 (11%) of these patients. In 82 (48%) of the 172 patients who fulfilled the inclusion criteria neurophysiological tests did not contribute to the final diagnosis. Neurophysiological criteria for demyelination were fulfilled in only 13 (8%) of the 172 patients. Conclusion: In patients presenting with signs and symptoms of chronic polyneuropathy the number of tests in the diagnostic investigation can be considerably reduced. In patients with signs and symptoms of polyneuropathy, providing the clinical phenotype is typical, in the presence of diabetes mellitus, renal failure, HIV infection, alcoholism, or use of potentially neurotoxic drugs further investigations are non-contributory. The significance of electrophysiological studies in the investigation of patients with polyneuropathy is rather to separate sensorimotor neuropathies from pure sensory neuropathies than to distinguish between demyelinating and axonal neuropathies.  相似文献   
88.
The quality of care received by mothers and babies in developing countries is often reported as poor. Yet efforts to address this contributory factor to maternal and newborn mortality have received less attention compared with barriers of access to care. The current heightened concern to achieve Millennium Development Goals 4 & 5 has illuminated the neglected quality agenda. Whilst there is no universally-accepted definition of "quality care", it is widely acknowledged to embrace multiple levels – from patient to health system, and multiple dimensions, including safety as well as efficiency. Quality care should thus lie at the core of all strategies for accelerating progress towards MDG4 &5. Interventions to measure and improve quality need themselves to be evidence-based. Two promising approaches are maternal and perinatal death reviews and criterion-based audit. These and other quality improvement tools have a crucial role to play in the implementation of effective maternal and newborn care.  相似文献   
89.
Chromosome band 11q23 is frequently involved in acute myeloid leukemia (AML) and acute lymphoblastic leukemia (ALL) de novo, as well as in myelodysplastic syndromes (MDS) and lymphoma. Five percent to 15% of patients treated with chemotherapy for a primary neoplasm develop therapy-related AML (t-AML) that may show rearrangements, usually translocations involving band 11q23 or, less often, 21q22. These leukemias develop after a relatively short latent period and often follow the use of drugs that inhibit the activity of DNA-topoisomerase II (topo II). We previously identified a gene, MLL (myeloid-lymphoid leukemia or mixed-lineage leukemia), at 11q23 that is involved in the de novo leukemias. We have studied 17 patients with t-MDS/t-AML, 12 of whom had cytogenetically detectable 11q23 rearrangements. Ten of the 12 t-AML patients had received topo II inhibitors and 9 of these, all with balanced translocations of 11q23, had MLL rearrangements on Southern blot analysis. None of the patients who had not received topo II inhibitors showed an MLL rearrangement. Of the 5 patients lacking 11q23 rearrangements, some of whom had monoblastic features, none had an MLL rearrangement, although 4 had received topo II inhibitors. Our study indicates that the MLL gene rearrangements are similar both in AML that develops de novo and in t-AML. The association of exposure to topo II- reactive chemotherapy with 11q23 rearrangements involving the MLL gene in t-AML suggests that topo II may play a role in the aberrant recombination events that occur in this region both in AML de novo and in t-AML.  相似文献   
90.
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