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排序方式: 共有200条查询结果,搜索用时 31 毫秒
41.
Shia T. Kent Samantha G. Bromfield Greer A. Burkholder Louise Falzon Suzanne Oparil Edgar T. Overton Michael J. Mugavero Joseph E. Schwartz Daichi Shimbo Paul Muntner 《PloS one》2016,11(2)
Introduction
Abnormal diurnal blood pressure (BP) rhythms may contribute to the high cardiovascular disease risk in HIV-positive (HIV+) individuals. To synthesize the current literature on ambulatory BP monitoring (ABPM) in HIV+ individuals, a systematic literature review and meta-analysis were performed.Methods
Medical databases were searched through November 11, 2015 for studies that reported ABPM results in HIV+ individuals. Data were extracted by 2 reviewers and pooled differences between HIV+ and HIV-negative (HIV-) individuals in clinic BP and ABPM measures were calculated using random-effects inverse variance weighted models.Results
Of 597 abstracts reviewed, 8 studies with HIV+ cohorts met the inclusion criteria. The 420 HIV+ and 714 HIV- individuals in 7 studies with HIV- comparison groups were pooled for analyses. The pooled absolute nocturnal systolic and diastolic BP declines were 3.16% (95% confidence interval [CI]: 1.13%, 5.20%) and 2.92% (95% CI: 1.64%, 4.19%) less, respectively, in HIV+ versus HIV- individuals. The pooled odds ratio for non-dipping systolic BP (nocturnal systolic BP decline <10%) in HIV+ versus HIV- individuals was 2.72 (95% CI: 1.92, 3.85). Differences in mean clinic, 24-hour, daytime, or nighttime BP were not statistically significant. I2 and heterogeneity chi-squared statistics indicated the presence of high heterogeneity for all outcomes except percent DBP dipping and non-dipping SBP pattern.Conclusions
An abnormal diurnal BP pattern may be more common among HIV+ versus HIV- individuals. However, results were heterogeneous for most BP measures, suggesting more research in this area is needed. 相似文献42.
Restriction-map variation associated with the G6PD polymorphism in natural populations of Drosophila melanogaster 总被引:10,自引:0,他引:10
Restriction-map variation was studied in 126 copies of the G6pd region in X
chromosome lines of Drosophila melanogaster from North America, Europe, and
Africa. Special attention was focused on the distribution of variation
relative to the geographically variable polymorphism for two
electrophoretic variants. Nucleotide heterozygosity as determined by eight
six-cutter restriction enzymes for the 13-kb region is estimated, on the
basis of the worldwide sample, to be 0.065%, which is the lowest value
reported for any comparable region in the D. melanogaster genome.
Significant linkage disequilibrium between electrophoretic alleles and
restriction-site variation is observed for several sites. In contrast to
published studies of other genetic regions, there are large insertions that
reach significant frequencies and are found across considerable geographic
distances. There is a clustering of this variation inside the first large
intervening sequence of the G6PD gene.
相似文献
43.
Robert G. Sheath JoAnn M. Burkholder Julie A. Hambrook Amy M. Hogeland Elizabeth Hoy Michael E. Kane Mary O. Morison Alan D. Steinman Kathryn L. Van Alstyne 《Hydrobiologia》1986,140(2):183-191
The Wood River watershed, a small well-defined drainage basin in Rhode Island was monitored seasonally for all macrophytic
vegetation and various physical variables. Twenty-four segments, 20 m in length were sampled. Mean stream depth, width and
current velocity increased by 3 to 8 fold from 1st- to 4th-order segments. Light penetration was positively correlated with
the above variables (p < 0.05) and increased by 11 fold from the headwaters to the mouth during September when the riparian
canopy was maximum. 74 subgeneric taxa of macrophytes were collected in the Wood River basin, 36% algae, 13% bryophytes, 4%
vascular cryptograms and 45% angiosperms. The highest diversity occurred in the 4th-order segments throughout the year. Species
numbers were positively correlated with depth, width and light penetration (p < 0.05). Vascular plants dominated all orders,
but their proportion doubled from 1st- to 4th-order streams. Macrophyte cover was twice as high in the 4th-order segments
in June and September as in the other orders. Macrophyte abundance was positively correlated to light penetration and negatively
correlated to the ratio of nonvascular: vascular plants (p < 0.05). Two distinct clusters were found for the predominant species.
The first cluster contained mostly large angiosperms, which were rooted in sediments, while the second cluster was composed
of small epilithic algae and bryophytes. The moss, Fontinalis antipyretica, was the most frequent species, occurring in 51% of the samples and in all 4 orders throughout the year. 相似文献
44.
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47.
W E Burkholder 《Journal of economic entomology》1966,59(5):1110-1112
48.
Sander A Huisman Wendy Bijman-Lagcher Jan NM IJzermans Ron Smits Ron WF de Bruin 《Cell cycle (Georgetown, Tex.)》2015,14(14):2333-2339
Irinotecan is a widely used topoisomerase-I-inhibitor with a very narrow therapeutic window because of its severe toxicity. In the current study we have examined the effects of fasting prior to irinotecan treatment on toxicity and anti-tumor activity. FabplCre;Apc15lox/+ mice, which spontaneously develop intestinal tumors, of 27 weeks of age were randomized into 3-day fasted and ad libitum fed groups, followed by treatment with a flat-fixed high dose of irinotecan or vehicle. Side-effects were recorded until 11 days after the start of the experiment. Tumor size, and markers for cell-cycle activity, proliferation, angiogenesis, and senescence were measured. Fasted mice were protected against the side-effects of irinotecan treatment. Ad libitum fed mice developed visible signs of discomfort including weight loss, lower activity, ruffled coat, hunched-back posture, diarrhea, and leukopenia. Irinotecan reduced tumor size in fasted and ad libitum fed groups similarly compared to untreated controls (2.4 ± 0.67 mm and 2.4 ± 0.82 mm versus 3.0 ± 1.05 mm and 2.8 ± 1.08 mm respectively, P < 0.001). Immunohistochemical analysis showed reduced proliferation, a reduced number of vascular endothelial cells, and increased levels of senescence in tumors of both irinotecan treated groups. In conclusion, 3 days of fasting protects against the toxic side-effects of irinotecan in a clinically relevant mouse model of spontaneously developing colorectal cancer without affecting its anti-tumor activity. These results support fasting as a powerful way to improve treatment of colorectal carcinoma patients. 相似文献
49.
Eric Burkholder 《Inorganica chimica acta》2006,359(1):261-266
The hydrothermal reaction of CuBr2 and tpyprz in the presence of NH4VO3 and HF for 72 h at 170 °C provided [(tpyprz)3Cu10Br10] (1) in 20% yield. The two-dimensional structure of 1 may be described as Cu(I)-tpyprz chains, linked through {Cu4Br5}− clusters in the ac-plane and decorated with {Cu3Br5}2− clusters projecting from one face of the layer in the b-direction. The Cu(I) sites exhibit distorted trigonal coordination {CuBr3} and distorted tetrahedral geometries, {CuBr2N2} and {CuN4}. Crystal data for 1: monoclinic space group C2, a = 12.7561(8) Å, b = 19.359(1) Å, c = 15.860(1) Å, β = 97.178(1)°, V = 3885.8(4) Å3, Z = 2, Dcalc = 2.222 g cm−3, μ(Mo Kα) = 78.75 cm−1. 相似文献
50.