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11.
Cefalu WT; Wagner JD; Bell-Farrow AD; Edwards IJ; Terry JG; Weindruch R; Kemnitz JW 《Toxicological sciences》1999,52(2):49-55
Caloric restriction (CR) has been observed to retard aging processes and
extend the maximum life span in rodents. In an effort to evaluate the
effect of this nutritional intervention on physiologic variables in higher
species, several nonhuman primate trials are ongoing. In particular, a
study evaluating the independent effect of CR on the extent of
atherosclerosis was initiated in 1993 in 32 adult cynomolgus monkeys.
Therefore, the trial was designed to achieve identical cholesterol intake
after animals were randomized to a control group or a calorie-restricted
group (30% reduction from baseline caloric intake). The animals were
routinely evaluated for glycated proteins, plasma insulin and glucose
levels, insulin sensitivity, and specific measures for abdominal fat
distribution by CT scans over a 4-year interval. The results from 4 years
of intervention demonstrate that CR improves cardiovascular risk factors
(such as visceral fat accumulation) and improves insulin sensitivity. In
contrast to other primate studies with normolipidemic animals, CR had no
independent effects on plasma lipid levels and composition in the presence
of equivalent amounts of dietary cholesterol intake. Preliminary analysis
of atherosclerotic lesion extent in the abdominal aorta has failed to
demonstrate differences between control animals and CR animals. Follow- up
studies are being conducted to determine the effect of CR on
atherosclerosis extent in coronary and carotid arteries.
相似文献
12.
Aeilko H. Zwinderman Ton J. Cleophas Bas van Ouwerkerk 《Clinical Research and Regulatory Affairs》2013,30(2):85-95
Current clinical trials do not use random samples, but, instead, convenience samples. This raises the risk of non-normal data.The aim of this paper is to review and describe for a non-mathematical readership common methods for testing the normal property, as well as methods for analyzing the data in case of non-normality.With slight departures from the normal distribution, normality tests can be used even so. They include, among other tests, the normal-, t-, chi-square- tests, analysis of variance, and regression analyses. They should not be used if the chi-square goodness of fit is significant. Rank-testing is, then, an alternative, but, sometimes, distributions do not allow for this approach either. This can be checked by the Kolmogorov-Smirnov test. If the latter test is also positive, rank-testing is not warranted, and confidence intervals can be derived from the data without prior assumption about the type of frequency distribution. This can be done by calculating the range within which 95% of all possible outcomes lie. Another popular method for this purpose is bootstrapping, which resamples at random from the study's own data. This paper reviews methods to assess data for compliance with normality, and summarizes solutions for the analysis of non-normal data. We strongly believe that normality statistics, although the mainstay of statistical analysis for centuries, will rapidly be replaced with non-normal testing as the awareness of non-normal sampling distributions grows, and we hope that the paper will strengthen this awareness and affect the design and analysis of future clinical trials. 相似文献
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14.
Roberto J. Staneloni María José Rodriguez-Batiller Danilo Legisa María R. Scarpin Adamantia Agalou Pablo D. Cerdán Annemarie H. Meijer Pieter B. F. Ouwerkerk Jorge J. Casal 《Proceedings of the National Academy of Sciences of the United States of America》2009,106(32):13624-13629
Plant responses mediated by phytochrome A display a first phase saturated by transient light signals and a second phase requiring sustained excitation with far-red light (FR). These discrete outcomes, respectively so-called very-low-fluence response (VLFR) and high-irradiance response (HIR), are appropriate in different environmental and developmental contexts but the mechanisms that regulate the switch remain unexplored. Promoter analysis of a light-responsive target gene revealed a motif necessary for HIR but not for VLFR. This motif is required for binding of the Bell-like homeodomain 1 (BLH1) to the promoter in in vitro and in yeast 1-hybrid experiments. Promoter substitutions that increased BLH1 binding also enhanced HIR. blh1 mutants showed reduced responses to continuous FR and to deep canopy shadelight, but they retained normal responses to pulsed FR or red light and unfiltered sunlight. BLH1 enhanced BLH1 expression and its promotion by FR. We conclude that BLH1 specifically regulates HIR and not VLFR of phytochrome A. 相似文献
15.
16.
Wouter Ouwerkerk Jasper Tromp John G.F. Cleland Christiane E. Angermann Ulf Dahlstrom Georg Ertl Mahmoud Hassanein Sergio V. Perrone Mathieu Ghadanfar Anja Schweizer Achim Obergfell Kenneth Dickstein Gerasimos Filippatos Sean P. Collins Carolyn S.P. Lam 《European journal of heart failure》2023,25(1):43-51
17.
18.
IJ Webb ; CE Eickhoff ; AD Elias ; LJ Ayash ; CA Wheeler ; GN Schwartz ; GD Demetri ; KC Anderson 《Transfusion》1996,36(2):160-167
BACKGROUND: Peripheral blood progenitor cells (PBPCs) are commonly collected and used to reconstitute hematopoiesis after high-dose chemotherapy. However, strategies for optimal collection and assessment of leukapheresis components are not standardized. STUDY DESIGN and METHODS: Hematopoietic progenitor cell assays were performed on 369 leukapheresis components collected from 95 patients who had received doxorubicin-based chemotherapy and/or granulocyte-colony-stimulating factor (G-CSF). Precollection patient hematologic values, leukapheresis collection values, component hematopoietic progenitor cell assays, and patient outcome measures were summarized. The kinetics of mononuclear cell (MNC) and PBPC mobilization were assessed among four patient groups. RESULTS: Patient group was a significant predictor of the peripheral blood MNC count on the day of collection (p<0.0001), and that value was a significant predictor of granulocyte-macrophage– colony-forming unit (CFU-GM) yield (p<0.0001). This relationship between the peripheral blood MNC count on the day of collection and CFU- GM yield differed according to patient group (p<0.0001). CFU-GM made up a larger fraction of peripheral blood MNCs collected from patients who received chemotherapy plus G-CSF than collected from those who received G-CSF alone. Moreover, the peripheral blood MNC count and the corresponding CFU-GM yield increased significantly on consecutive days of collection in patient groups receiving chemotherapy and G-CSF but were unchanged or decreased in patients receiving G-CSF alone. CONCLUSION: The relationship between peripheral blood MNC count and leukapheresis component CFU-GM yield differed significantly between patients who received chemotherapy and G-CSF and those who received G- CSF alone for the mobilization of PBPCs. Patient peripheral blood MNC count and component CFU-GM yield are useful for both assessing and suggesting revisions to PBPC mobilization and collection strategies. 相似文献
19.
van der Sluijs JA van Ouwerkerk WJ de Gast A Wuisman P Nollet F Manoliu RA 《The Journal of bone and joint surgery. British volume》2002,84(4):583-587
We undertook a prospective MRI study to measure the retroversion of the humeral head in 33 consecutive infants with a mean age of 1 year 10 months (3 months to 7 years 4 months) who had an obstetric brachial plexus lesion (OBPL). According to a standardised MRI protocol both shoulders and humeral condyles were examined and the shape of the glenoid and humeral retroversion determined. The mean humeral retroversion of the affected shoulder was significantly increased compared with the normal contralateral side (-28.4 +/- 12.5 degrees v -21.5 +/- 15.1 degrees, p = 0.02). This increase was found only in the children over the age of 12 months. In this group humeral retroversion was -29.9 +/- 12.9 degrees compared with -19.6 +/- 15.6 degrees in the normal shoulder (p = 0.009), giving a mean difference of 10.3 degrees (95% confidence interval 3.3 to 17.3). This finding is of importance when considering the operative treatment for subluxation of the shoulder in children with an OBPL. 相似文献
20.
Chen YC; Wang CH; Su IJ; Hu CY; Chou MJ; Lee TH; Lin DT; Chung TY; Liu CH; Yang CS 《Blood》1989,74(1):388-394
Among 354 adult patients with either hematological malignancy or aplastic anemia, eight were positive for anti-HTLV-I antibodies; six of eight had received multiple transfusions. There was an approximately 3.5-fold increase (P less than .001) of HTLV-I seropositivity in the patients with hematologic disease (8 of 354, 2.23%) compared to the healthy adults older than 20 years (34 of 5252, .65%). Two hematological patients, one with Hodgkin's disease and one with acute promyelocytic leukemia, were found to be positive for HTLV-I, and developed and died of adult T-cell leukemia/lymphoma (ATL) subsequently. Both were long-term survivors of the primary disease and had received multiple transfusions. The latent period from blood transfusion to onset of ATL was 6 months and 11 years, respectively. Immunocompromised patients, who were seropositive for HTLV-I, may be at increased risk for ATL compared to healthy carriers of HTLV-I, and the latent period may be shorter. 相似文献