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61.
Clendenen TV Koenig KL Arslan AA Lukanova A Berrino F Gu Y Hallmans G Idahl A Krogh V Lokshin AE Lundin E Muti P Marrangoni A Nolen BM Ohlson N Shore RE Sieri S Zeleniuch-Jacquotte A 《Cytokine》2011,56(3):769-778
Epidemiological studies have reported associations between circulating inflammation markers and risk of chronic diseases. It is of interest to examine whether risk factors for these diseases are associated with inflammation. We conducted a cross-sectional analysis to evaluate whether reproductive and lifestyle factors and circulating vitamin D were associated with inflammation markers, including C-reactive protein, cytokines (IL-1β, IL-2, IL-4, IL-5, IL-6, IL-10, IL-12p40, IL-12p70, IL-13, TNFα), and cytokine modulators (IL-1RA, sIL-1RII, sIL-2Ra, sIL-4R, sIL-6R, sTNF-R1/R2), among 616 healthy women. We confirmed associations of several inflammation markers with age and BMI. We also observed significantly higher levels of certain inflammation markers in postmenopausal vs. premenopausal women (TNFα, sIL-1RII, sIL-2Ra), with increasing parity (IL-12p40), and with higher circulating 25(OH) vitamin D (IL-13) and lower levels among current users of non-steroidal anti-inflammatory drugs (NSAIDs) (IL-1β, IL-2, IL-10, IL-12p70, and IL-12p40), current smokers (IL-4, IL-13, IL-12p40), and women with a family history of breast or ovarian cancer (IL-4, IL-10, IL-13). Our findings suggest that risk factors for chronic diseases (age, BMI, menopausal status, parity, NSAID use, family history of breast and ovarian cancer, and smoking) are associated with inflammation markers in healthy women. 相似文献
62.
Kostenko O van de Voorde TF Mulder PP van der Putten WH Martijn Bezemer T 《Ecology letters》2012,15(8):813-821
Root herbivory can greatly affect the performance of aboveground insects via changes in plant chemistry. These interactions have been studied extensively in experiments where aboveground and belowground insects were feeding on the same plant. However, little is known about how aboveground and belowground organisms interact when they feed on plant individuals that grow after each other in the same soil. We show that feeding by aboveground and belowground insect herbivores on ragwort (Jacobaea vulgaris) plants exert unique soil legacy effects, via herbivore-induced changes in the composition of soil fungi. These changes in the soil biota induced by aboveground and belowground herbivores of preceding plants greatly influenced the pyrrolizidine alkaloid content, biomass and aboveground multitrophic interactions of succeeding plants. We conclude that plant-mediated interactions between aboveground and belowground insects are also important when they do not feed simultaneously on the same plant. 相似文献
63.
Driscoll MK McCann C Kopace R Homan T Fourkas JT Parent C Losert W 《PLoS computational biology》2012,8(3):e1002392
We observe and quantify wave-like characteristics of amoeboid migration. Using the amoeba Dictyostelium discoideum, a model system for the study of chemotaxis, we demonstrate that cell shape changes in a wave-like manner. Cells have regions of high boundary curvature that propagate from the leading edge toward the back, usually along alternating sides of the cell. Curvature waves are easily seen in cells that do not adhere to a surface, such as cells that are electrostatically repelled from surfaces or cells that extend over the edge of micro-fabricated cliffs. Without surface contact, curvature waves travel from the leading edge to the back of a cell at -35 μm/min. Non-adherent myosin II null cells do not exhibit these curvature waves. At the leading edge of adherent cells, curvature waves are associated with protrusive activity. Like regions of high curvature, protrusive activity travels along the boundary in a wave-like manner. Upon contact with a surface, the protrusions stop moving relative to the surface, and the boundary shape thus reflects the history of protrusive motion. The wave-like character of protrusions provides a plausible mechanism for the zig-zagging of pseudopods and for the ability of cells both to swim in viscous fluids and to navigate complex three dimensional topography. 相似文献
64.
‘Public diplomacy’ is a term increasingly used among policy makers and academics, yet its meaning is ambiguous and contested. Advocates proclaim it as a new approach to statecraft entailing a participatory approach of shared meaning‐making between politicians and the public markedly different from the elitist, Machiavellian inter‐governmental practices of traditional (‘Westphalian’) diplomacy. The European Union (EU) has embraced these ideals, proclaiming public diplomacy a cornerstone of European external relations policy. We examine these claims in the context of the EU's delegations to Australia and New Zealand. Using three ethnographic case studies, we highlight discrepancies between official discourses on public diplomacy and its practice. The participatory ideals of EU public diplomacy, we argue, are undermined by the EU's preoccupation with image and branding, public relations and marketing techniques, and continuing reliance on traditional ‘backstage’ methods of diplomacy. We conclude by outlining the implications of these paradoxes for both anthropological research and EU external relations. 相似文献
65.
W. R. Mitchell D. G. Lindburg S. E. Shideler S. Presley B. L. Lasley 《International journal of primatology》1985,6(2):161-172
Sexual behaviors were recorded and urinary concentrations of total estrogens and pregnanediol-3-glucuronide (Pdg) measured
during six normal menstrual cycles from two female lowland gorillas in a stable, captive group. Frequencies of female presentations,
mounts, and copulations were positively associated with peak estrogen values but not with elevations of Pdg. These results
support the observation that sexual behaviors in the gorilla occur most frequently in the periovulatory period and that copulations
serve primarily a sexual function. 相似文献
66.
Kris Pruski Tess Astatkie Jerzy Nowak 《In vitro cellular & developmental biology. Plant》2002,38(2):203-209
Summary Jasmonic acid (JA) effects on in vitro tuberization of potato nodal explants cvs. Sangre and Russet Burbank were tested under liquid and solid media conditions
and 0,8, and 16h photoperiod. Explants taken from stock plants grown on 2.5μM JA-supplemented medium tuberized first, particularly in darkness. The most pronounced benefits of the JA pretreatment were
recorded under 16h photoperiod, which is known to inhibit tuberization. Cultivar Sangre benefited from the JA preconditioning
of stock plants more than Russet Burbank. Russet Burbank required the JA supplement in tuberization media to reach the same
degree of stimulation. Overall, microtubers produced either from JA preconditioned stock plants or on the JA-containing tuberization
media were more uniform and larger than from other treatments. Eight hours photoperiod was by far the best treatment for the
production of high-quality uniform microtubers. JA conditioning of stock plants prior to taking explants for tuberization
is being proposed as a treatment enhancing the quality of microtubers. 相似文献
67.
Early embryonic death (EED) was studied in 354 pregnant mares during two breeding seasons. Pregnant mares from six independent research projects were examined at 15, 20, 25, 30, 35, 40 and 50 days post-ovulation using a real-time ultrasound scanner. Mares that had previously been treated with anabolic steroids tended (P<0.10) toward a higher incidence of EED than untreated mares (21.1% vs 0%). Of the 59 pregnancies obtained from embryo transfer in 1982, 10 had undergone EED by day 50 (16.9%) compared to 10.1% for embryo transfer recipients in 1983. Overall, there was a 13.3% incidence of EED in embryo transfer recipients. This percentage was nearly identical to 13.4% incidence of EED for mares inseminated with fresh semen. In 1982, mares inseminated with frozen-thawed semen tended (P<0.10) to have a higher incidence of EED compared to those inseminated with fresh semen (34.6% vs 15.8%). However, in 1983 there was no difference (P>0.05) in the incidence of EED between mares inseminated with frozen-thawed and fresh semen (16.7% vs 12.5%). Further, combined over both years, there was no difference (P>0.10) in the incidence of EED (24.2% vs 14.4%). There was a 38.9% incidence of EED in infertile mares.Of the 354 pregnant mares, the overall incidence in EED through day 50 postovulation was 17.3%. The majority of EED (77.1%) occurred prior to day 35 post-ovulation. During the period 15 to 35 days post-ovulation, a greater (P<0.05) incidence of EED occurred between days 15 to 20 (26.2%) and 30 to 35 (29.5%) post-ovulation. 相似文献
68.
The enzyme sialyltransferase (STase) of Neisseria gonorrhoeae is a major pathogenicitiy determinant. Using a refined method for assaying the STase activity, the Km for CMP-NANA was shown to be 14 +/– 2 M, higher than that reported previously. Rates of sialylation by Nonidet extracts, prepared under conditions that optimise solubilisation of the membrane-bound enzyme, were 6 to 20 nmol of NANA transferred from CMP-14C-NANA onto isolated lipopolysaccharide/min./mg of extracted protein, far higher than the previously reported rates of less than 1 nmol of NANA transferred/min./mg of extracted protein. Gonococci grew more slowly with lactate or pyruvate than with glucose as the carbon source. Although growth with a mixture of limiting concentrations of both glucose and lactate was biphasic, diauxic growth was also found in the control culture supplied with glucose alone. The growth rate in the presence of lactate alone was slower than with glucose. The growth rate increased slightly relative to the glucose culture when both substrates were available; lactate was consumed more rapidly than glucose. Higher STase activities were found in bacteria harvested in the exponential than in the stationary phase of aerobic growth: the activity in aerated cultures was higher than those of oxygen-limited or anaerobic cultures. Similar STase activities were found in bacteria that had been grown with glucose, lactate or pyruvate as the carbon and energy source. Sialyltransferase synthesis is essentially constitutive: it is not regulated by glucose repression or by induction by lactate or anaerobiosis. 相似文献
69.
Hematologic values for 99 tule elk (Cervus elaphus nannodes) from California (USA) are presented. These were obtained from individuals from three captures at Tomales Point (Point Reyes National Seashore, California) from 1997-98. Differences between capture groups were assessed. Greatest differences were detected between yearling bulls and cows in December 1998 which may be a reflection of age and reproductive status. 相似文献
70.
Shideler SE Gee NA Chen J Laughlin LS Rapp PR Morrison JH Roberts JA Moran FM Lasley BL 《American journal of primatology》2003,61(3):111-121
This study was designed to test the hypothesis that basal estrone conjugate (E1C) profiles do not accurately detect ovarian function when ovarian estrogen production is low or absent. We employed surgical removal of active ovaries from laboratory rhesus macaques to simulate an acute decline in ovarian estrogen production. In the first experiment, urine samples collected prior to and following ovariectomy (Ovx) were subjected to high-performance liquid chromatography (HPLC) separation. Eluates were then assayed for E1C immunoreactive components. The results indicated a modest decrease in total immunoreactive polar conjugates following ovariectomy, with no substantial change in the overall retention profile. In the second experiment, estradiol (E2) cypionate injections were used to replace the E2 component of ovarian estrogen production in the treated (Tx) group, while the control group (C) received only vehicle. Urine samples were hydrolyzed and individual estrogens were separated by celite chromatography prior to immuno-assay. Both the Tx and C groups exhibited similar urinary excretion levels of estrone (E1), E2, and E1C prior to Ovx (Pre-Ovx) and after Ovx (Post-Ovx), but there were significant differences between groups after treatment (Post-Tx). Significant differences were observed in the Tx group's excretion of E1, E2, and E1C in the Pre- vs. Post-Ovx samples and in the Post-Ovx and Post-Tx samples. The C group also showed the expected significant differences in the Pre- vs. Post-Ovx samples, as well as in the Pre-Ovx and Post-Tx samples. The results indicate that the use of E1C measurements is clearly a suitable method for monitoring ovarian function in intact, cycling animals, but urinary E2 measurements are required to verify loss of follicular activity. 相似文献