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41.
Mary M. Zheng Zhifang Zhang Kyle Bemis Andrew R. Belch Linda M. Pilarski John E. Shively Julia Kirshner 《PloS one》2013,8(3)
Multiple myeloma (MM) is an incurable bone marrow malignancy of the B cell lineage. Utilizing multiplex Luminex technology we measured levels of 25 cytokines in the plasma of normal donors (n = 177), those with monoclonal gammopathy of undetermined significance (n = 8), and MM patients (n = 55) with either active disease, on treatment, or in remission. The cytokine levels were compared between normal donors and MM patients as well as between various phases of MM, and discriminant analysis was used to create a predictive classification model based on the differentially expressed cytokines. Evaluating age- and gender-dependence of cytokine expression, we determined that with age there is a shift toward a pro-inflammatory environment. Moreover, we observed a strong gender bias in cytokine expression. However, the profile of differentially expressed cytokines was heavily skewed toward an anti-inflammatory, pro-tumorigenic response in patients with MM. Significantly, our predictive model placed all patients in remission in the same category as those with active disease. Thus, our study demonstrates that the homeostasis of systemic cytokines is not restored when MM patients enter remission, suggesting that once an individual has cancer, the microenvironment is permanently altered and the system is primed for a relapse. 相似文献
42.
Ephedrine administered subcutaneously or in the diet reduces the weight of viable yellow obese mice (/) and normal mice. The compound has some appetite-suppression activity; however, reduced food consumption could not account for all of the weight loss. Ephedrine did not affect lipogenesis or lipolysis acutely. The major portion of the weight loss was due to the loss of triacylglycerol. The rectal temperature of long-term treated / mice was elevated suggesting that ephedrine may alter energy metabolism. 相似文献
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Kinematics of swimming of penguins at the Detroit Zoo 总被引:2,自引:0,他引:2
Kinematic parameters were examined in a study of the swimming abilities of seven species of penguins housed at the Detroit Zoo. Penguins produce thrust over both halves of the wing stroke cycle, as observed in fishes using the caudal or pectoral fins for locomotion, but not in other birds in level forward flight. Unpowered gliding phases between wing strokes were observed in all species at swimming speeds less than 1.25 m/sec, while Emperor, King and Adelie penguins interpose gliding phases over a broad range of speeds. Videotape records reveal that length-specific speed is correlated with increases in wingbeat frequency and, for most of the species examined, stride length. These findings are in contrast to those reported for other, flying birds, which maintain a relatively constant wingbeat frequency but vary stride length with forward speed, and for most fishes, which vary speed with tailbeat frequency but maintain a constant stride length. The results are somewhat comparable to those reported for Cymatogaster , a fish which uses the pectoral fins for locomotion. Drag coefficients of three gliding Emperor penguins were 2.1, 3.0 and 3.0 × 10-−3 at Reynolds numbers of 1.25, 1.62 and 1.76 × 106 , respectively. 相似文献
45.
Genetic Education for Native Americans (GENA) was a National Human Genome Research Institute (NHGRI)/Ethical, Legal, and Social Implications (ELSI)-funded educational intervention designed to provide a unique genetics education program for Native American college and university students. A curriculum was developed and implemented in workshops in geographically diverse settings throughout the United States, primarily in conjunction with regional and national scientific conferences that include substantial numbers of Native American attendees. The original curriculum includes 24 objectives and has been offered in two formats, as a 16-hr "comprehensive" program and in briefer workshops (referred to as "customized" hereafter) that are designed to include objectives for selected audiences. Both formats teach sufficient genetics to allow discussion and understanding of the ELSI and cultural issues related to genetics science. This article describes the evaluation findings from our implementation of both formats of the GENA curriculum. 相似文献
46.
Li F Bielke W Ke G Andres AC Jaggi R Saurer S Friis RR Niemann H Bemis L Geske FJ Strange R 《Cell death and differentiation》1995,2(2):113-122
Although apoptosis is important in determining cell fate and maintaining tissue homeostasis, the initiation and control of apoptotic cell death in epithelium is not well understood. Post-lactationai involution of the mammary gland provides both an important developmental process and a normal physiological setting for studying apoptosis of epithelium. We used a differential screening strategy, based on previous studies correlating morphology with gene expression and nucleic acid integrity during mammary gland involution, to isolate genes involved in the regulation and execution of apoptotic cell death in regressing mammary epithelium. This screening strategy yielded a large number of genes the expression of which is significantly altered during mammary gland involution. These include genes associated with cell death processes, tissue remodelling and mesenchymal differentiation. In addition, a number of novel genes have been isolated. We have used Northern analysis and in situ hybridisation to study the expression of a selection of these putative death-associated genes during post-lactational mouse mammary gland involution. 相似文献
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1. Differing responses in riparian species richness and composition to disturbance have been reported as a possible explanation for the differences along and between rivers. This paper explores the role of physical disturbance in shaping landscape‐scale patterns of species distribution in riparian vegetation along a free‐flowing river in northern Sweden. 2. To test whether sensitivity to disturbance varies across large landscapes, we experimentally disturbed riparian vegetation along an entire, free‐flowing river by scouring the soil and the vegetation turf, cutting vegetation, applying waterborne plant litter, and after a period of recovery we measured vegetation responses. The experiment was repeated for two consecutive years. 3. We found no significant effect of disturbance on species composition, but all three forms of disturbance significantly reduced species richness. There was no downstream variation in community responses to disturbance but morphological groups of species responded differently to different kinds of disturbance. Graminoids were most resistant, suppressed only by litter burial. All forms of disturbance except cutting reduced the density of herbaceous species, and species density of trees + shrubs and dwarf shrubs was negatively affected by both scouring and cutting. We also evaluated the effects of disturbance in relation to varying levels of species richness. In nearly all cases, responses were significantly negatively correlated with control plot species richness, and relative responses indicated that species‐rich plots were less resistant to scouring and cutting. 4. Our results suggest that although all disturbance treatments had an effect on species richness, variation in sensitivity to disturbance is not the most important factor shaping landscape‐scale patterns of riparian plant species richness along rivers. 相似文献
50.
M. Lia Palomba Kelly Piersanti Carly G. K. Ziegler Hugo Decker Jesse W. Cotari Kurt Bantilan Ivelise Rijo Jeff R. Gardner Mark Heaney Debra Bemis Robert Balderas Sami N. Malek Erlene Seymour Andrew D. Zelenetz Marcel R. M. van den Brink Grégoire Altan-Bonnet 《PloS one》2014,9(1)