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1.
The effect of in ovo administration of ovine growth hormone (oGH) on growth and adipose tissue development of chickens was investigated. Unlike mammalian species, exogenous growth hormone has not been previously shown to increase growth of aves. In trial 1, fertilized eggs were injected with vehicle (.03 M NaHCO3 in .15 M NaCl, pH 8.3), 0.25, 2.5, 25 or 250 micrograms oGH on day 11 of embryogenesis. In trial 2, fertile eggs were injected with vehicle or 250 micrograms oGH. In contrast to previous studies in which GH was administered to growing birds, oGH injected in ovo in the present study increased body weights, skeletal growth and feed efficiencies of male broilers. Growth rate was not altered in females. Adipose cellularity data from both trials indicated that in ovo oGH also altered adipose tissue development of broilers. Seven-week-old male and female broilers treated with oGH during embryogenesis exhibited larger adipocytes with correspondingly less cell per gram of tissue. Additionally, adipocytes from oGH-treated broilers exhibited decreased sensitivity to glucagon, cholera toxin or theophylline-induced lipolysis responsiveness to dcAMP in ovo. Cholera toxin plus theophylline improved the lipolytic response of oGH-treated birds; thus, in broilers injected with oGH cAMP-mediated lipase activation may be reduced by a mechanism of increased phosphodiesterase activity. The results of this study indicate that growth and tissue development of chickens have been altered by mammalian GH in ovo. 相似文献
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Katrine G. Fjeld Morten Mowe Hilde Eide Tiril Willumsen 《European journal of oral sciences》2014,122(2):142-148
A single‐blinded, randomized controlled clinical trial was performed to investigate the effect of electric toothbrushes (ET) compared with manual toothbrushes (MT) on residents in nursing homes and to evaluate the caregiver's opinion on ET. A sample of 180 nursing‐home residents were given either a new ET or a new MT. Oral examinations were performed to measure dental hygiene, using the Oral Hygiene Index‐Simplified (OHI‐S). Both groups received the same instructions for use. After 2 months participants were re‐examined. Questionnaires were then sent to their caregivers. Participants' mean age was 86.1 ± 7.7 yr, and the mean number of remaining teeth was 20 ± 5.6. No specific intervention effect was found for ET. Both groups showed identical improvements in the OHI‐S, from 1.27 ± 0.63 at baseline (the mean value for all participants) to 1.01 ± 0.53 after 2 months. Of 152 caregivers who responded to the questionnaire, the majority evaluated ET to be beneficial and less time‐consuming compared with MT, also for demented residents. In a frail population, no difference is found in the effect of ET compared with MT. However, the ET appears to be a useful aid for residents who receive assistance with dental hygiene. 相似文献
5.
Christine Lamanna Benjamin Blonder Cyrille Violle Nathan J. B. Kraft Brody Sandel Irena ?ímová John C. Donoghue II Jens-Christian Svenning Brian J. McGill Brad Boyle Vanessa Buzzard Steven Dolins Peter M. J?rgensen Aaron Marcuse-Kubitza Naia Morueta-Holme Robert K. Peet William H. Piel James Regetz Mark Schildhauer Nick Spencer Barbara Thiers Susan K. Wiser Brian J. Enquist 《Proceedings of the National Academy of Sciences of the United States of America》2014,111(38):13745-13750
The processes causing the latitudinal gradient in species richness remain elusive. Ecological theories for the origin of biodiversity gradients, such as competitive exclusion, neutral dynamics, and environmental filtering, make predictions for how functional diversity should vary at the alpha (within local assemblages), beta (among assemblages), and gamma (regional pool) scales. We test these predictions by quantifying hypervolumes constructed from functional traits representing major axes of plant strategy variation (specific leaf area, plant height, and seed mass) in tree assemblages spanning the temperate and tropical New World. Alpha-scale trait volume decreases with absolute latitude and is often lower than sampling expectation, consistent with environmental filtering theory. Beta-scale overlap decays with geographic distance fastest in the temperate zone, again consistent with environmental filtering theory. In contrast, gamma-scale trait space shows a hump-shaped relationship with absolute latitude, consistent with no theory. Furthermore, the overall temperate trait hypervolume was larger than the overall tropical hypervolume, indicating that the temperate zone permits a wider range of trait combinations or that niche packing is stronger in the tropical zone. Although there are limitations in the data, our analyses suggest that multiple processes have shaped trait diversity in trees, reflecting no consistent support for any one theory.Species richness increases toward the equator (1, 2) in major clades of both extant and extinct species of plants and animals (3, 4). The generality of the pattern hints at a correspondingly general explanation, yet the latitudinal gradient in species richness remains one of ecology’s greatest unsolved puzzles. Long-running debates over the causes of the latitudinal gradient of species richness have focused on ecological, evolutionary, and geographic explanations (5–10). Although there has been some progress (11), it is also increasingly clear that there are numerous obstacles to understanding the primary drivers of the latitudinal gradient, including an ever-increasing number of hypotheses (12, 13), challenges in clearly separating their interdependencies (14, 15), and difficulties in rigorously falsifying their assumptions and predictions (16).More powerful tests of biodiversity theories need to move beyond species richness and instead explicitly focus on the mechanisms generating the gradient, by recasting the theories in terms of other measures of diversity, such as functional diversity (17–19). For example, explanations that assume species richness is limited by resource availability have often focused on the strength of species interactions, life history differences, and environmental constraints on how species pack into niche space (20). Evolutionary hypotheses have focused on differences in diversification rates, as well as the influence of species interactions on diversification rates (9). These interaction-based explanations implicitly refer to the degree of ecological differentiation among species, and therefore to trait dispersion within clades and assemblages, suggesting that patterns of functional diversity may provide a more powerful test of theory than taxonomic richness (21).A particularly important concept that unifies many ecological and evolutionary theories is the concept of the Hutchinsonian multidimensional niche (22). Hutchinsonian niches can be quantified by assessing the functional trait hypervolumes that characterize phenotypic space occupied by a set of species. Quantifying the volume, overlap, and packing of functional trait space at different spatial scales enables inferences about how differing ecological and evolutionary processes structure functional diversity and ecological strategies (23, 24).Here, we recast several contrasting hypotheses for the latitudinal gradient in terms of functional trait space. We focus on the proximate ecological mechanisms that ultimately can influence evolutionary processes. We quantify tree functional trait space across latitude at three spatial scales: (i) within assemblages (alpha), (ii) among assemblages (beta), and (iii) among biomes (gamma). For alpha and beta analyses, we use tree species assemblage data from 620 standardized 0.1-ha forest plots (Fig. 1A); for gamma analyses, we calculated the latitudinal range distributions for 520 New World tree species where we had sufficient data on geographic distribution and functional traits. In total, across all analyses, we used paired geographic occurrence data with trait data for 6,839 tree species.Open in a separate windowFig. 1.(A) Spatial distribution of the 620 0.1-ha forest plots used in this study. Plots are colored by richness. Plots cover most of the New World forested climate space (Fig. S1). (B) Relationship between absolute latitude and alpha hypervolume for tropical (red triangles) and temperate (blue pluses) plots. (C) Alpha hypervolume as a function of effective species richness (number of species with full trait coverage). We compare this hypervolume with a null expectation based on sampling the same number of species from the regional pool (median, dark gray line; 90% quantile range, light gray envelope).We primarily measured hypervolumes for three central traits hypothesized to characterize major axes of ecological strategy variation (25): specific leaf area (SLA), maximum height, and seed mass. SLA represents the tradeoff between leaf longevity and maximum photosynthetic rate (26); height is important for light competition and dispersal (27); and seed mass represents tradeoffs between fecundity, dispersal, and seedling survival (27). Although whole-plant resource strategies can be more fully assessed in higher dimensions (28, 29), we focus on these traits because of data availability (Materials and Methods). We use a hypervolume algorithm for calculating the volume and overlap of trait space (30) (Materials and Methods). All hypervolumes are reported in units of SDs of centered and scaled log-transformed trait values, raised to the power of the number of trait dimensions used.At all scales, our overall results and conclusions are similar (i) with and without gap-filling missing data, (ii) if we use convex hulls instead of hypervolumes to calculate trait spaces, and (iii) if we include additional trait axes. Additional details are given in Figs. S2–S7. 相似文献
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The effects of dental fear treatments were assessed in a 1-year follow-up study. Sixty-two patients had finished a controlled study in which they were randomly allocated to nitrous oxide sedation (NO), cognitive therapy (CT), or applied relaxation (AR). During the trial highly significant reductions in dental fear and general distress were observed. One year later a majority (95%) of the participants had attended dental treatment in general practice. On the whole, continued favorable effects with regard to dental fear and general distress were observed. Patients in the applied relaxation group evidenced the largest reductions on the dental fear measures. All patients judged the dental fear treatment to have been beneficial, and 80% judged the treatment given in the year after the dental fear treatment successful. All three treatment groups scored in the normative range for general distress both at the end of treatment and at follow-up. 相似文献
7.
Background
Microvascular decompression (MVD) is a documented effective treatment of trigeminal neuralgia (TN). Lately, reports on endoscopy-assisted microvascular decompression (eaMVD) with better outcome and less risk have emerged. This study was undertaken to verify under which circumstances the endoscope proved essential in identifying the neurovascular conflict (NVC) during eaMVD for TN, and to assess the possibility to predict the need for the endoscope on preoperative magnetic resonance imaging (MRI).Methods
Retrospective analysis of 97 patients with TN undergoing eaMVD at the Oslo University Hospital – Rikshospitalet, 1999–2009. To assess the NVC and anatomical variations, surgical reports were evaluated. MRI was available in 66 patients. The MRIs were evaluated by a blinded neuroradiologist.Results
In 27 of the 97 patients (27.8 %), the endoscope was a significant aid in identifying the NVC, due to a bony ridge obscuring the view of the fifth nerve, a very distal vascular compression, or a combination of both. The preoperative MRI over-diagnosed the presence of a bony ridge. However, the MRI-based fraction of microscopically visible trigeminal nerve (FVN) in the cerebellopontine angle cistern proved diagnostic (ROC curve, AUC 0.89, p?=?<0.001) with an optimal cut-off value of 0.35. Hence, if less than 35 % of the trigeminal nerve is visible on preoperative MRI, the endoscope will be needed to identify the NVC.Conclusions
The endoscope is a valuable tool during MVD for TN, especially under anatomical circumstances such as a bony ridge hiding the direct microscopic view of the NVC. These anatomical circumstances can be predicted with good accuracy on preoperative MRI. 相似文献8.
Five years after completing a controlled, randomized treatment trial comparing the effect of nitrous oxide sedation (NO), cognitive therapy (CT), and applied relaxation (AR), all 62 patients who had participated were invited to a follow-up questionnaire study. Forty-three responded. All participants had been to the dentist during the follow-up period. Mean scores (s) on Corah's Dental Anxiety Scale (CDAS) and Symptom Checklist 90 Revised (SCL-90-R, a measure of general psychological distress) were 10.4 (4.1) and 0.35 (0.34), respectively. There were no between-group effects. Significant changes across the assessment phases (at enrollment, after treatment, and 5 years after) were found for both dental fear and general distress (CDAS: F = 137.8, P < 0.01; SCL-90-R: F = 12.5, P < 0.01). However, no significant changes between measures obtained after treatment and at follow-up emerged. Seven participants (3 from the NO group, 2 from the CT group, and 2 from the AR group) had CDAS scores above 14, indicating a recurrent or continual dental fear problem. The majority (81%) assessed the dental fear treatment received 5 years previously to have been useful for them. In conclusion, the favorable effects on dental fear and general psychological distress continued at 5-year follow-up for all treatment groups. 相似文献
9.
R. R. Provine S. C. Sharma T. T. Sandel V. Hamburger 《Proceedings of the National Academy of Sciences of the United States of America》1970,65(3):508-515
Unit electrical activity was recorded from single neurons in the lumbo-sacral spinal cord of 15-, 17-, and 19-day chick embryos, in situ. The dorsal columns showed relatively continuous single-unit activity. Below this lies an area of relative quiet 100-200mu deep. The ventral two thirds of the cord was the most active region, being characterized by polyneuronal bursts and intermittently active single units. 相似文献
10.
Building geographic information system capacity in local health departments: lessons from a North Carolina project
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Miranda ML Silva JM Overstreet Galeano MA Brown JP Campbell DS Coley E Cowan CS Harvell D Lassiter J Parks JL Sandelé W 《American journal of public health》2005,95(12):2180-2185
State government, university, and local health department (LHD) partners collaborated to build the geographic information system (GIS) capacity of 5 LHDs in North Carolina. Project elements included procuring hardware and software, conducting individualized and group training, developing data layers, guiding the project development process, coordinating participation in technical conferences, providing ongoing project consultation, and evaluating project milestones. The project provided health department personnel with the skills and resources required to use sophisticated information management systems, particularly those that address spatial dimensions of public health practice. This capacity-building project helped LHDs incorporate GIS technology into daily operations, resulting in improved time and cost efficiency. Keys to success included (1) methods training rooted in problems specific to the LHD, (2) required project identification by LHD staff with associated timelines for development, (3) ongoing technical support as staff returned to home offices after training, (4) subgrants to LHDs to ease hardware and software resource constraints, (5) networks of relationships among LHDs and other professional GIS users, and (6) senior LHD leadership who supported the professional development activities being undertaken by staff. 相似文献