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91.
Current practices for viability testing of cryopreserved cord blood products: an international survey by the cellular therapy team of the Biomedical Excellence for Safer Transfusion (BEST) Collaborative 下载免费PDF全文
92.
Kensaku Kawamoto Cary J Martin Kip Williams Ming-Chieh Tu Charlton G Park Cheri Hunter Catherine J Staes Bruce E Bray Vikrant G Deshmukh Reid A Holbrook Scott J Morris Matthew B Fedderson Amy Sletta James Turnbull Sean J Mulvihill Gordon L Crabtree David E Entwistle Quinn L McKenna Michael B Strong Robert C Pendleton Vivian S Lee 《J Am Med Inform Assoc》2015,22(1):223-235
Objective To develop expeditiously a pragmatic, modular, and extensible software framework for understanding and improving healthcare value (costs relative to outcomes).Materials and methods In 2012, a multidisciplinary team was assembled by the leadership of the University of Utah Health Sciences Center and charged with rapidly developing a pragmatic and actionable analytics framework for understanding and enhancing healthcare value. Based on an analysis of relevant prior work, a value analytics framework known as Value Driven Outcomes (VDO) was developed using an agile methodology. Evaluation consisted of measurement against project objectives, including implementation timeliness, system performance, completeness, accuracy, extensibility, adoption, satisfaction, and the ability to support value improvement.Results A modular, extensible framework was developed to allocate clinical care costs to individual patient encounters. For example, labor costs in a hospital unit are allocated to patients based on the hours they spent in the unit; actual medication acquisition costs are allocated to patients based on utilization; and radiology costs are allocated based on the minutes required for study performance. Relevant process and outcome measures are also available. A visualization layer facilitates the identification of value improvement opportunities, such as high-volume, high-cost case types with high variability in costs across providers. Initial implementation was completed within 6 months, and all project objectives were fulfilled. The framework has been improved iteratively and is now a foundational tool for delivering high-value care.Conclusions The framework described can be expeditiously implemented to provide a pragmatic, modular, and extensible approach to understanding and improving healthcare value. 相似文献
93.
Mahon NG Hedman AE Padula M Gang Y Savelieva I Waktare JE Malik MM Huikuri HV McKenna WJ 《European journal of heart failure》2002,4(2):151-158
BACKGROUND AND AIM: asymptomatic relatives of patients with familial dilated cardiomyopathy who have left ventricular enlargement [LVE] are at risk for progression to dilated cardiomyopathy. A novel index of the fractal correlation properties of heart rate variability (HRV), the short-term scaling component (proportional, variant(1)) in detrended fluctuation analysis, is a promising prognostic tool in left ventricular dysfunction. The aim of this study was to compare values of proportional, variant(1) and conventional HRV indices in LVE relatives with dilated cardiomyopathy patients and normal controls. METHODS: time-domain and spectral HRV measures, and the short-term scaling component ( proportional, variant(1)) were assessed from 24-h Holter recordings from 22 LVE relatives (left ventricular end-diastolic dimension >112% predicted, normal fractional shortening), 24 dilated cardiomyopathy patients and 14 controls. RESULTS: the time domain index SDNN was lower in dilated cardiomyopathy patients [101.8(+/-44.0)] than in LVE relatives [161.7(+/-53.9)] or controls [152.9(+/-51.4)], P=0.01. Similarly, triangular index and spectral measures were reduced in dilated cardiomyopathy patients but not in LVE relatives or controls. In contrast, the short term scaling component ( proportional, variant(1)) in detrended fluctuation analysis was reduced in both dilated cardiomyopathy patients [1.06(+/-0.33)] and in LVE relatives [1.15 (+/-0.20)], compared with controls [1.32(+/-0.16)], P=0.01. Among DCM patients the short-term scaling component ( proportional, variant(1)) was significantly associated with echocardiographic deterioration during follow-up (3.7+/-2.1 year) (P=0.004). CONCLUSION: the short-term scaling component ( proportional, variant(1)) is reduced in asymptomatic relatives of dilated cardiomyopathy patients who have LVE. 相似文献
94.
E Rowland W J McKenna D Sugrue R Barclay R A Foale D M Krikler 《British heart journal》1984,51(1):15-24
Electrophysiological studies showed ventricular tachycardia in five patients (four male, one female) with isolated right ventricular dilatation. All had been asymptomatic before the onset of palpitation which had developed in adolescence or early adult life. Tachycardia had been associated with syncope in four patients, and three had been resuscitated from ventricular fibrillation before investigation. The electrocardiogram during ventricular tachycardia showed a left bundle branch block pattern, and endocardial mapping at electrophysiological study confirmed the right ventricular origin. The presenting tachycardia could be induced in all patients by programmed stimulation, and in three patients ventricular tachycardia of differing configuration could be induced, but the right ventricular origin and left bundle branch block pattern were maintained. In two patients ventricular tachycardia degenerated into ventricular fibrillation. Cineangiography, cross sectional echocardiography, and multigated radionuclide angiography confirmed the dilated abnormal right ventricle while indicating that left ventricular function was normal. On resting electrocardiograms T wave inversion over the right precordial leads was the sole abnormality. There were no signs of right heart failure and exercise tolerance was normal. Four patients have received maintenance treatment with antiarrhythmic drugs, and one had undergone operative mapping and ablative surgery. Thus ventricular tachycardia complicating right ventricular dilatation may be associated with serious symptoms and ventricular electrical instability; and in adults it may be suspected on clinical grounds by inverted T waves in the right precordial leads. 相似文献
95.
Apical hypertrophic cardiomyopathy appears to be more common in Japan than in the West. Explanations for this difference include variable methods and criteria for the diagnosis. To assess morphological, clinical, and prognostic differences, 45 consecutive Japanese and 45 age- and gender-matched Western patients with hypertrophic cardiomyopathy were evaluated in two referral institutions by the same individuals. The diagnosis of hypertrophic cardiomyopathy was based on the echocardiographic demonstration of unexplained left ventricular hypertrophy. Patients were aged 8 to 64 years (mean 50); there were 66 males and 24 females. The pattern of left ventricular hypertrophy was similar in Japanese and Western patients: asymmetric septal 64 vs. 76%, concentric 22 vs. 13%, and apical 13 vs. 11% (p = NS). The incidence of an echocardiographic or Doppler calculated left ventricular gradient of > 30 mmHg was similar (11 vs. 18%; p = NS). The maximal left ventricular wall thickness was greater in Western patients (23 +/- 7 vs. 20 +/- 4 mm; p = 0.03), but was not different when adjusted for body surface area. Clinical features including incidence of family history and ventricular tachycardia during 24-h ambulatory electrocardiography were similar. During follow-up (4.9 +/- 4.0 years for Western vs. 4.4 +/- 2.0 years for Japanese), disease-related mortality was worse in Western patients (p < 0.05; 10 versus 2 patients). This evaluation, using the same diagnostic methods and criteria, reveals a worse prognosis in Western patients despite a similar clinical and morphological spectrum of hypertrophic cardiomyopathy. 相似文献
96.
97.
A simple chemosensory response in Drosophila and the isolation of acj mutants in which it is affected. 总被引:5,自引:2,他引:5 下载免费PDF全文
M McKenna P Monte S L Helfand C Woodard J Carlson 《Proceedings of the National Academy of Sciences of the United States of America》1989,86(20):8118-8122
Although the Drosophila visual system has been described extensively, little is known about its olfactory system. A major reason for this discrepancy has been the lack of simple, reliable means of measuring response to airborne chemicals. This paper describes a jump response elicited by exposing Drosophila to chemical vapors. This behavior provides the basis for a single-fly chemosensory assay. The behavior exhibits dose dependence and chemical specificity: it is stimulated by exposure to ethyl acetate, benzaldehyde, and propionic acid but not ethanol. Animals can respond repeatedly at short intervals to ethyl acetate and propionic acid. The response relies on the third antennal segments. To illustrate the use of this behavior in genetic analysis of chemosensory response, nine acj mutants defective in response are isolated (acj = abnormal chemosensory jump), and their responses to two chemicals are characterized. All of the acj mutants are normal in giant fiber system physiology, and two exhibit defects in visual system physiology. 相似文献
98.
Pretreatment lymph nodes, bone marrow, and blood were examined in 176 cases of non-Hodgkin's lymphoma. By the criteria of the Lukes and Collins functional--morphological classification, 158 (90%) were B-cell lymphomas and 17 (10%) were T-cell lymphomas. Bone marrow involvement was present in 53% of cases: 51% of B-cell types and 65% of T-cell types. Marrow involvement was most frequent in small lymphocyte (B) (89%), convoluted lymphocyte (60%), and small cleaved follicular center cell (FCC) lymphomas (55%). The pattern of bone marrow involvement was most frequently focal paratrabecular in B-cell lymphomas and diffuse in T-cell lymphomas. Blood involvement was present in 50% of cases with bone marrow lymphoma and generally reflected extensive bone marrow disease. There was a higher incidence of both bone marrow and blood involvement in pediatric patients than in adults. 相似文献
99.
Tumour-infiltrating T lymphocytes (TIL-T) have been implicated in playing a role in controlling tumour growth. We evaluated TIL-T in 55 cases of de novo diffuse large B-cell lymphoma (DLBCL) using three- or four-colour flow cytometric immunophenotyping (FCI). The percentage of TIL-T varied from 3% to 72% of total viable cellular events (mean 32 +/- 20%). The CD4:CD8 ratio varied from 0.17 to 13 (mean 2.3 +/- 2.2). Cases with >/= 20% T cells and those with CD4:CD8 ratios > or = 2.0 showed a significantly better overall survival (P = 0.017 and P = 0.034 respectively). These findings were independent of clinical stage at diagnosis. The T-cell percentage and CD4:CD8 ratio were moderately correlated (Spearman correlation coefficient = 0.47, P = 0.001) and multivariate analysis revealed that the association of the two factors with prognosis was mutually dependent. The T cells in 23 cases were studied for CD45RO. The mean percentage of total T cells expressing CD45RO was 86 +/- 10%. There was a trend towards better survival for those patients with a higher percentage of CD45RO+ T cells (P = 0.06). These results suggest that TIL-T, particularly CD4+ T cells, may play a role in the control of DLBCL, and measurement of T-cell percentage and T-cell subsets using FCI may be useful in predicting the clinical behaviour of DLBCL. 相似文献
100.
Left lower lobe ventilation is reduced in patients with cardiomegaly in the supine but not the prone position 总被引:4,自引:0,他引:4
C M Wiener W J McKenna M J Myers J P Lavender J M Hughes 《The American review of respiratory disease》1990,141(1):150-155
To determine the effect of the heart on regional ventilation, Krypton-81m (81mKr) tomographic (SPECT) ventilation scans were recorded in seven patients with cardiomegaly and four normal subjects in the supine and prone positions. All patients had a cardiothoracic ratio of greater than 0.50 and clear lung fields radiographically. Using standard gamma camera tomographic reconstruction techniques, images of transaxial slices were obtained during a 360 degree rotation around the thorax of the subject breathing the radioactive gas 81mKr. The transaxial images, acquired over 10 min were aligned in each posture at the level of the cardiac apex, mid-heart, and aortic arch and were matched in relation to a radioactive marker on the chest wall and to anatomic landmarks. A horizontal line (gravity independent and parallel to the couch) was drawn on the transaxial section through the dorsal regions of the right and left lung. Counts per resolution element (12 to 15 mm) were plotted along this line and the ratios of the peak values in right and left lung compared. These ratios represent differences in regional ventilation per unit lung volume. In controls the mean left-to-right (L/R) peak count ratio varied from 0.91 to 1.00 at the three levels (range: 0.76 to 1.04); there were no significant differences between supine and prone. In patients with cardiomegaly the mean (+/- SEM) L/R peak count ratio at cardiac apex, mid-heart, and aortic arch was 0.46 (+/- 0.08), 0.55 (+/- 0.07), and 0.89 (+/- 0.08) when supine and 1.04 (+/- 0.07), 1.05 (+/- 0.05), and 1.08 (+/- 0.07) when prone, respectively.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献