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21.
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摘要 目的:探讨清热化痰、宣肺解痉法治疗支气管哮喘的临床疗效及对气道呼吸参数、生活质量的影响。方法:选取我院2019年10月到2021年9月收治的60例支气管哮喘患者作为研究对象,分为观察组与对照组,每组30例。对照组予吸入布地奈德福莫特罗粉吸入剂,观察组在对照组基础上增加清热化痰宣肺解痉法治疗,对比两组患者临床疗效,治疗前与治疗1个月后的中医证候积分变化,气道呼吸参数变化,炎症因子以及生活质量变化。结果:观察组总有效率较对照组高(P<0.05);两组患者治疗前中医证候积分对比无差异(P>0.05),治疗后降低,且观察组低于对照组(P<0.05);两组患者治疗前第1秒用力呼气容积(FEV1)、用力肺活量(FVC)、第1s用力呼气量/用力肺活量(FEV1/FVC)最大呼气流速(PEF)对比无明显差异(P>0.05),治疗后两组患者FVC、FEV1、FEV1/ FVC、PEF均有提升,且观察组高于对照组(P<0.05);两组患者治疗前肿瘤坏死因子-α(TNF-α)、转化生长因子-β1(TGF-β1)、基质金属蛋白-9(MMP-9)、血管内皮生长因子(VEGF)、干扰素-γ(IFN-γ)、白细胞介素-4(IL-4)水平对比无明显差异(P>0.05),治疗后两组患者TNF-α、TGF-β1、MMP-9、VEGF、IFN-γ、IL-4水平均明显降低,且观察组低于对照组(P<0.05);两组患者治疗前生活质量评分对比无差异(P>0.05),治疗后1个月生活质量相关评分均降低,且观察组较对照组低(P<0.05)。结论:支气管哮喘患者在常规西医治疗基础上增加清热化痰宣肺解痉法治疗可减轻患者症状。另外可改善患者呼吸功能,降低炎症因子反应,提升患者生活质量。  相似文献   
23.
1. Cross‐ecosystem movements of resources, including detritus, nutrients and living prey, can strongly influence food web dynamics in recipient habitats. Variation in resource inputs is thought to be driven by factors external to the recipient habitat (e.g. donor habitat productivity and boundary conditions). However, inputs of or by ‘active’ living resources may be strongly influenced by recipient habitat quality when organisms exhibit behavioural habitat selection when crossing ecosystem boundaries. 2. To examine whether behavioural responses to recipient habitat quality alter the relative inputs of ‘active’ living and ‘passive’ detrital resources to recipient food webs, we manipulated the presence of caged predatory fish and measured biomass, energy and organic content of inputs to outdoor experimental pools of adult aquatic insects, frog eggs, terrestrial plant matter and terrestrial arthropods. 3. Caged fish reduced the biomass, energy and organic matter donated to pools by tree frog eggs by ~70%, but did not alter insect colonisation or passive allochthonous inputs of terrestrial arthropods and plant material. Terrestrial plant matter and adult aquatic insects provided the most energy and organic matter inputs to the pools (40–50%), while terrestrial arthropods provided the least (7%). Inputs of frog egg were relatively small but varied considerably among pools and over time (3%, range = 0–20%). Absolute and proportional amounts varied by input type. 4. Aquatic predators can strongly affect the magnitude of active, but not passive, inputs and that the effect of recipient habitat quality on active inputs is variable. Furthermore, some active inputs (i.e. aquatic insect colonists) can provide similar amounts of energy and organic matter as passive inputs of terrestrial plant matter, which are well known to be important. Because inputs differ in quality and the trophic level they subsidise, proportional changes in input type could have strong effects on recipient food webs. 5. Cross‐ecosystem resource inputs have previously been characterised as donor‐controlled. However, control by the recipient food web could lead to greater feedback between resource flow and consumer dynamics than has been appreciated so far.  相似文献   
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Summary

In insects, the regulation of embryonic development has been intensively studied in model species like Drosophila melanogaster. Previous comparative studies have suggested that the developmental processes documented in Drosophila well describe embryogenesis of holometabolous insects generally. However, there have been few attempts to take into account how life history has influenced insect embryogenesis or to characterize early development of species with life histories fundamentally different from flies. Our studies of advanced insects in the order Hymenoptera suggest that punctuated shifts in life history can profoundly influence these events. In particular, alterations associated with the evolution of endoparasitism argue that departures from the fly paradigm may occur commonly among insects that develop under conditions different from typical terrestrial species.  相似文献   
26.
The spider mite Tetranychus urticae shows variation in its dispersal capacity (i.e., the leaf quality at which a female decides to disperse). We were able to artificially select mites that had either a high or a low dispersal capacity, indicating that this trait was genetically controlled. We then compared correlated responses to this selection. Mites with a genetically high dispersal capacity (‘HD’ strains) had a higher diapause incidence and a lower performance compared to mites with a low dispersal capacity (‘LD’ strains). A possible effect of random genetic drift during the selection was negligible. Our results suggest that differential dispersal capacity is associated with contrasting life history patterns as a result of natural selection. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
27.
The generation time ofP. branickii was studied using larval samples in conjunction with rearing experiments and continuous collection of egg masses across one year. This species produced three generations per year in a central German stream (280 m a.s.l., 50° 40 N). Its generation time was variable and obviously influenced by the photoperiod to which eggs and larvulae were subjected. It is thus concluded that two strains ofP. branickii were present in a single population, one bivoltine and the other trivoltine.  相似文献   
28.
Northern forest ecosystems are exposed to a range of anthropogenic processes including global warming, atmospheric deposition, and changing land‐use. The vegetation of northern forests is composed of species with several functional traits related to these processes, whose effects may be difficult to disentangle. Here, we combined analyses of spatio‐temporal dynamics and functional traits of ground flora species, including morphological characteristics, responses to macro‐ and microclimate, soil conditions, and disturbance. Based on data from the Swedish National Forest Inventory, we compared changes in occurrence of a large number of ground flora species during a 20‐year period (1994–2013) in boreal and temperate Sweden respectively. Our results show that a majority of the common ground flora species have changed their overall frequency. Comparisons of functional traits between increasing and declining species, and of trends in mean trait values of sample plots, indicate that current floristic changes are caused by combined effects of climate warming, nitrogen deposition and changing land‐use. Changes and their relations with plant traits were generally larger in temperate southern Sweden. Nutrient‐demanding species with mesotrophic morphology were favored by ongoing eutrophication due to nitrogen deposition in the temperate zone, while dwarf shrubs with low demands on nitrogen decreased in frequency. An increase of species with less northern and less eastern distribution limits was also restricted to temperate Sweden, and indicates effects of a moister and milder macroclimate. A trend toward dense plantation forests is mirrored by a decrease of light‐demanding species in both vegetation zones, and a decrease of grassland species in the temperate zone. Although denser tree canopies may buffer effects of a warmer climate and of nitrogen deposition to some extent, traits related to these processes were weakly correlated in the group of species with changing frequency. Hence, our results indicate specific effects of these often confounded anthropogenic processes.  相似文献   
29.
Various physiological and psychological functions are influenced by circadian typology (CT), which was reported to be related to resilience. However, few studies have assessed the effects of CT in relation to resilience. The aim of the present study was to assess the influence of CT on sleep-related symptoms, physical fatigue and psychological well-being in relation to resilience. The present study included a total of 1794 healthy hospital employees, and they completed the Morningness–Eveningness Questionnaire, Connor–Davidson Resilience Scale, Pittsburgh Sleep Quality Index, Epworth Sleepiness Scale, Fatigue Severity Scale, Hospital Anxiety and Depression Scale and World Health Organization Quality of Life Scale Abbreviated Version. Subjects with evening type showed lower sleep quality, more daytime sleepiness and physical fatigue than neither types and morning types. Additionally, evening types were more depressed and anxious and reported a poorer quality of life. CT was found to be a significant predictor of sleep quality, but CT was minimally associated with physical fatigue and psychological well-being in the regression analysis. Instead, resilience was substantially related to all of the variables measured. In conclusion, CT independently predicts sleep quality, but the effects of CT on physical fatigue and psychological well-being are negligible compared to those of resilience.  相似文献   
30.
The effect of sublethal levels of methylparathion (0, 1, 3, 5, 7 mg l–1) on the freshwater rotifer, Brachionus calyciflorus, during their entire life cycle was studied. Rotifers were fed on two species of unicellular algae: Nannochloris oculata and Chlorella pyrenoidosa; both algal concentrations were 5 × 105 cell ml–1.The parameters used to determine the toxicity of this compound were survival, fecundity, net reproductive rate (R)o, generation time (T), intrinsic rate of natural increase (r), reproductive value (V x/Vo) and life expectancy at hatching (eo). All the demographic parameters studied were affected by methyl-parathion exposure on rotifers fed on both species of algae, but the toxic effect was larger when animals were fed on Chlorella pyrenoidosa; in this case, animals showed a decreased in fertility and also a delayed first reproduction. Sublethal methylparathion levels produced a reduction in most of the parameters selected, especially after exposure to 7 mg l–1, where the animals died before reproducing.  相似文献   
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