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241.
目的:了解泰山沙参属植物资源现状,测定其根中脂肪、蛋白质及多糖的含量,为合理开发利用泰山沙参属植物资源提供依据。方法:采用野外实地调查法进行资源考察;分别用索氏提取法、考马斯亮蓝法和苯酚-硫酸法测定脂肪、蛋白质和多糖的含量。结果:采集的100余份标本,经鉴定为沙参属植物狭叶沙参[Adenophora gmeli-nii(Spreng)Fisch.]、石沙参(Adenophora polyantha Nakai)、杏叶沙参(Adenophora stricta Mig.)及细叶沙参(Adeno-phora paniculata Nannf.)。泰山沙参属植物狭叶沙参、石沙参、杏叶沙参和细叶沙参脂肪含量分别为2.14%~7.34%,4.27%~7.72%1,.54%~2.51%和4.98%。蛋白质含量分别为0.60~2.10 mg/g0,.80~1.89 mg/g,0.83~0.89 mg/g和1.05 mg/g,多糖含量分别为20.58%~63.21%2,7.74%~65.14%,43.14%~48.47%和45.60%。结论:泰山野生沙参属植物资源丰富,品种多、分布广、蕴藏量大,多糖含量较高,具有较大的开发前景。 相似文献
242.
243.
Gine Roll Skjærvø Terje Bongard Åslaug Viken Bård G. Stokke Eivin Røskaft 《Evolution and human behavior》2011,32(5):305-314
Wealth and status covary with lifetime reproductive success in preindustrial human populations. Local ecology is likely to modify this association, but details of this presumed relationship are not yet known. We sought to determine whether local ecology modifies the relationship between status and fitness (number of grandchildren). Our approach to the problem was to measure variation in fitness relative to status (landless or with land) and to local ecology (inland versus coastal communities). We also analyzed life history traits that might explain observed variations in fitness. Our results confirm previous findings that both status (landless=9.9 vs. with land=16.5) and ecology (inland=12.3 vs. coast=14.1) affect the number of grandchildren produced by a female in pre-industrial society. We also found that the differences in number of children between the status groups were less pronounced on the coast (landless=12.0 vs. with land=16.1) than inland (landless=7.8 vs. with land=16.8). Our findings are novel because they suggest that the fitness consequences of human status may depend on details of local ecology. We discuss four different mechanisms that could account for these fitness differences: (1) differential reproductive rate of mothers, (2) differential marriage rate of children (3) differential survival rate of children, and (4) different social practices (breastfeeding, inheritance of property and diet). 相似文献
244.
Summary Australia is committed to protecting its important and representative ecosystems. Foremost among protection measures is the network of terrestrial and marine protected areas that comprise the National Reserve System (NRS). However, these reserves were often established with little regard for the conservation needs of riverine ecosystems. There has been no conservation status assessment to determine whether riverine ecosystems are adequately protected within terrestrial reserves. This study begins this task by determining the extent of riverine protection through the NRS. Three classes of protection are defined based on the proportion of the catchment of each stream segment (the link between tributary confluences) that is contained within a protected area, and the presence of major in‐stream barriers. The analysis reveals cause for concern. While nearly 225 000 km (7.6%) of the 2.9 million kilometres of streams assessed fall within a protected area of IUCN class I to IV where the principal objective is nature conservation, just 12 334 km of stream, less than half of one per cent of the total stream length, receives Class A protection, the strongest level of protection against threat. Class A is achieved where an entire drainage basin is contained within a protected area. Most of the protected stream length of the larger, named streams is potentially threatened by land‐use activities occurring in unprotected headwaters or is fragmented by major dams and thus receives the lowest class of protection. Owing to a variety of pervasive threats, a more comprehensive conservation status assessment of these ecosystems would undoubtedly yield an even more pessimistic result. Such an assessment is recommended. 相似文献
245.
Foraging theory has typically been concerned with the acquisition of a single resource even though organisms from mammals to protozoa are capable of balancing their requirements for multiple resources. Existing theory concerning multiple nutrients from multiple foods does not predict the sequence of food selection. We constructed an optimisation model of the simplest case of two foods containing differing amounts of two nutrients. We begin with the well-supported assumption that reproductive value declines with the distance from target nutrient intake. We show that nutrient space divides into two distinct areas where the animal should exclusively consume one food or the other. The organism thus initially concentrates on one food type until the border between the areas is reached and then moves as closely as possible along the border to approach the target. This strategy is commonly observed in a range of organisms, suggesting that the assumed fitness function is common. 相似文献
246.
Paul W Jones James F Donohue Jerry Nedelman Steve Pascoe Gregory Pinault Cheryl Lassen 《Respiratory research》2011,12(1):161
Background
Relationships between improvements in lung function and other clinical outcomes in chronic obstructive pulmonary disease (COPD) are not documented extensively. We examined whether changes in trough forced expiratory volume in 1 second (FEV1) are correlated with changes in patient-reported outcomes.Methods
Pooled data from three indacaterol studies (n = 3313) were analysed. Means and responder rates for outcomes including change from baseline in Transition Dyspnoea Index (TDI), St. George''s Respiratory Questionnaire (SGRQ) scores (at 12, 26 and 52 weeks), and COPD exacerbation frequency (rate/year) were tabulated across categories of ΔFEV1. Also, generalised linear modelling was performed adjusting for covariates such as baseline severity and inhaled corticosteroid use.Results
With increasing positive ΔFEV1, TDI and ΔSGRQ improved at all timepoints, exacerbation rate over the study duration declined (P < 0.001). Individual-level correlations were 0.03-0.18, but cohort-level correlations were 0.79-0.95. At 26 weeks, a 100 ml increase in FEV1 was associated with improved TDI (0.46 units), ΔSGRQ (1.3-1.9 points) and exacerbation rate (12% decrease). Overall, adjustments for baseline covariates had little impact on the relationship between ΔFEV1 and outcomes.Conclusions
These results suggest that larger improvements in FEV1 are likely to be associated with larger patient-reported benefits across a range of clinical outcomes.Trial Registration
ClinicalTrials.gov , NCT00393458, and NCT00463567 NCT00624286相似文献247.
Abstract Fecundity in some insects is affected by mating status. The effect of mating status on the fecundity and total egg production of Teleogryllus emma (Ohmachi et Matsumura) (Orthoptera: Gryllidae) was examined in this study. The results showed that the pre‐oviposition period was shorter for amphigonic females than that for virgin females. However, no significant difference in pre‐oviposition was found between amphigonic females and those that had mated with a male with either the phallodeum or testes extirpated. There is no difference in adult longevity between the above four groups. The fecundity and total egg production were much higher in amphigonic females than in those controlled under the three non‐amphigonic treatments. The females of T. emma that mated with the testes‐extirpated males produced more eggs (up to two‐fold more) than both the virgin females and those that mated with the phallodeum‐extirpated males, but there was no difference between them. The fecundity‐enhancing substances transferred from male to female can stimulate the female to produce more eggs, but this stimulation has to occur in collaboration with sperm. 相似文献
248.
冯菁张兴凯赵森张作鹏党晓莉 《现代生物医学进展》2011,11(9):1757-1759
目的:探讨高通量血液透析对尿毒症患者营养状况的影响。方法:自身对照研究将38例维持性低通量血液透析患者转换为高通量血液透析(HPD),HPD组使用日本旭化成APS-15u高通量透析器6个月,分别采用改良主观全面营养评估(MQSGA)及各项客观营养指标进行相关性分析。结果:经转换为高通量血液透析后主观全面营养评估较使用低通量血液透析有显著性差异;营养相关指标血清白蛋白(ALB)、血红蛋白较前有明显提高,差异有显著性(P<0.05);胆固醇较前相比无明显差异。结论:高通量血液透析能有效改善维持性透析患者的营养状况。 相似文献
249.
It is widely assumed that terrestrial food webs are built on a nitrogen-limited base and consequently herbivores must compensate through selection of high-protein foods and efficient nitrogen retention. Like many folivorous primates, gorillas' diet selection supports this assumption, as they apparently prefer protein-rich foods. Our study of mountain gorillas (Gorilla beringei) in Uganda revealed that, in some periods, carbohydrate-rich fruits displace a large portion of protein-rich leaves in their diet. We show that non-protein energy (NPE) intake was invariant throughout the year, whereas protein intake was substantially higher when leaves were the major portion of the diet. This pattern of macronutrient intake suggests that gorillas prioritize NPE and, to achieve this when leaves are the major dietary item, they over-eat protein. The concentrations of protein consumed in relation to energy when leaves were the major portion of the diet were close to the maximum recommended for humans and similar to high-protein human weight-loss diets. By contrast, the concentrations of protein in relation to energy when gorillas ate fruit-dominated diets were similar to those recommended for humans. Our results question the generality of nitrogen limitation in terrestrial herbivores and provide a fascinating contrast with human macronutrient intake. 相似文献
250.
Background: Marital status has been associated with outcomes in several cancer sites including breast cancer in the literature, but little is known about colon cancer, the fourth most common cancer in the US. Methods: A total of 127,753 patients with colon cancer were identified who were diagnosed between 1992 and 2006 in the US Surveillance, Epidemiology and End Results (SEER) Program. Marital status consisted of married, single, separated/divorced and widowed. Chi-square tests were used to examine the association between marital status and other variables. The Kaplan–Meier method was used to estimate survival curves. Cox proportional hazards models were fit to estimate the effect of marital status on survival. Results: Married patients were more likely to be diagnosed at an earlier stage (and for men also at an older age) compared with single and separated/divorced patients, and more likely to receive surgical treatment than all other marital groups (all p < 0.0001). The five-year survival rate for the single was six percentage points lower than the married for both men and women. After controlling for age, race, cancer stage and surgery receipt, married patients had a significantly lower risk of death from cancer (for men, HR: 0.86, CI: 0.82–0.90; for women, HR: 0.87, CI: 0.83–0.91) compared with the single. Within the same cancer stage, the survival differences between the single and the married were strongest for localized and regional stages, which had overall middle-range survival rates compared to in situ or distant stage so that support from marriage could make a big difference. Conclusions: Marriage was associated with better outcomes of colon cancer for both men and women, and being single was associated with lower survival rate from colon cancer. 相似文献