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21.
The organization of 14 exons covering 97% of the cDNA sequence of human cerebroside sulfate activator protein precursor has been determined from two overlapping EMBL-4 human genomic clones extending over 17kb. All exons and exon/intron splice junctions and five introns were sequenced. Exon 8 consists of only 9 bp and is involved in alternative splicing which generates three different mRNAs of cerebroside sulfate activator precursor.  相似文献   
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Proton pumping ATPases are found in all groups of present day organisms. The F-ATPases of eubacteria, mitochondria and chloroplasts also function as ATP synthases, i.e., they catalyze the final step that transforms the energy available from reduction/oxidation reactions (e.g., in photosynthesis) into ATP, the usual energy currency of modern cells. The primary structure of these ATPases/ATP synthases was found to be much more conserved between different groups of bacteria than other parts of the photosynthetic machinery, e.g., reaction center proteins and redox carrier complexes.These F-ATPases and the vacuolar type ATPase, which is found on many of the endomembranes of eukaryotic cells, were shown to be homologous to each other; i.e., these two groups of ATPases evolved from the same enzyme present in the common ancestor. (The term eubacteria is used here to denote the phylogenetic group containing all bacteria except the archaebacteria.) Sequences obtained for the plasmamembrane ATPase of various archaebacteria revealed that this ATPase is much more similar to the eukaryotic than to the eubacterial counterpart. The eukaryotic cell of higher organisms evolved from a symbiosis between eubacteria (that evolved into mitochondria and chloroplasts) and a host organism. Using the vacuolar type ATPase as a molecular marker for the cytoplasmic component of the eukaryotic cell reveals that this host organism was a close relative of the archaebacteria.A unique feature of the evolution of the ATPases is the presence of a non-catalytic subunit that is paralogous to the catalytic subunit, i.e., the two types of subunits evolved from a common ancestral gene. Since the gene duplication that gave rise to these two types of subunits had already occurred in the last common ancestor of all living organisms, this non-catalytic subunit can be used to root the tree of life by means of an outgroup; that is, the location of the last common ancestor of the major domains of living organisms (archaebacteria, eubacteria and eukaryotes) can be located in the tree of life without assuming constant or equal rates of change in the different branches.A correlation between structure and function of ATPases has been established for present day organisms. Implications resulting from this correlation for biochemical pathways, especially photosynthesis, that were operative in the last common ancestor and preceding life forms are discussed.  相似文献   
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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   
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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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Objective: To investigate the construct validity of the Short Form‐36 (SF‐36) Health Survey questionnaire in obese patients. Research Methods and Procedures: Our series consisted of 1735 obese patients (age, 44.7 ± 11.0 years; 1346 women) consecutively enrolled in the QUOVADIS study, an observational multicenter study of obese treatment‐seeking outpatients. The construct validity of the SF‐36 was assessed by main component analysis. Age‐, gender‐, and education‐adjusted general linear models were used to investigate the relationship between BMI and SF‐36 domains or factors identified by main component analysis. Results: BMI was significantly associated with poor health‐related quality of life in all eight SF‐36 domains, and the strongest association was observed with physical activity. Main components analysis generated a six‐factor solution explaining 59% of the observed variance. BMI was strongly associated with factors based on the loading of items regarding the physical activity domain and factors based on role‐physical and role‐emotional items or general health and bodily pain items. In contrast, mental health‐, vitality‐, and social functioning‐based factors were not related to BMI. Discussion: In obese treatment‐seeking outpatients, the clustering of SF‐36 items in main components is not significantly different from the domain‐based approach generally used, thus confirming the robustness of such a generic questionnaire in this specific condition. However, the peculiar clustering of some SF‐36 items and their relationship with BMI suggest that the health‐related quality of life profile of subjects belonging to that population may be better described with alternative aggregations of the SF‐36 items or with disease‐tailored questionnaires.  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   
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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   
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