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71.
Two new norlignans together with two known phenylpropanoids were isolated from the whole herb of Anemone vitifolia. All compounds were reported from this plant for the first time. The structures of these compounds were identified by comprehensive HR‐ESI‐MS, 1D and 2D NMR spectroscopic data analysis and comparison with literature data. Additionally, bioactivity study results showed that two new compounds have potential anti‐inflammatory activity. The plausible biosynthetic pathway for these compounds were also speculated in this article.  相似文献   
72.
The capacitance of microsupercapacitors (MSCs) can double if both sides of substrates are used to construct MSCs. Nevertheless, achieving electric connections of MSCs through substrates is a challenge due to the difficulty in precisely positioning each MSC couple that has two of the same MSCs units on two sides. In this work, taking advantage of the synchronous etching on both sides of transparent polyethylene terephthalate substrates by femtosecond laser pulses, a double‐sided configuration is attained with high precision in the alignment of back‐to‐back MSC couples and versatile double‐side MSCs are realized via arbitrary on‐ and through‐substrate connections of MXene MSC units. The MXene double‐side MSC fabricated by the series connection of 12 spiral pattern MXene MSC units with interdigital electrodes of 10 μm width interspace can output a large working voltage of 7.2 V. Additionally, femtosecond laser etching brings the transformation of MXene into titania near‐etched edges with a lateral distance less than 1 µm. Such a small laser‐affected area has little influence on the capacitive performance, which is one of advantages for femtosecond laser over conventional lasers. This research is valuable for one‐step manufacturing of highly integrated MSCs in the field of miniaturized energy storage systems.  相似文献   
73.
Poly(3,4‐ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) has been is applied as hole transport material in organic electronic devices for more than 20 years. However, the redundant sulfonic acid group of PEDOT:PSS has often been overlooked. Herein, PEDOT:PSS‐DA is prepared via a facile doping of PEDOT:PSS with dopamine hydrochloride (DA·HCl) which reacts with the redundant sulfonic acid of PSS. The PEDOT:PSS‐DA film exhibits enhanced work function and conductivity compared to those of PEDOT:PSS. PEDOT:PSS‐DA‐based devices show a power conversion efficiency of 16.55% which is the highest in organic solar cells (OSCs) with (poly[(2,6‐(4,8‐bis(5‐(2‐ethylhexyl)‐4‐fluorothiophen‐2‐yl)benzo[1,2‐b:4,5‐b′]dithio‐phene))‐co‐(1,3‐di(5‐thiophene‐2‐yl)‐5,7‐bis(2‐ethylhexyl)‐benzo[1,2‐c:4,5‐c′]dithiophene‐4,8‐dione))] (PM6):(2,2′‐((2Z,2′Z)‐((12,13‐bis(2‐ethylhexyl)‐3,9‐diundecyl‐12,13‐dihydro‐[1,2,5]thiadiazolo[3,4‐e]thieno[2′′,3′:4′,5′]thieno[2′,3′:4,5]pyrrolo[3,2‐g]thieno[2′,3′:4,5]thieno[3,2‐b]indole‐2,10‐diyl)bis(methanylylidene))bis(5,6‐difluoro‐3‐oxo‐2,3‐dihydro‐1H‐indene‐2,1‐diylidene))dimalononitrile) (Y6) as the active layer. Furthermore, PEDOT:PSS‐DA also exhibits enhanced performance in three other donor/acceptor systems, exhibiting high compatibility in OSCs. This work demonstrates that doping PEDOT:PSS with various amino derivatives is a potentially efficient strategy to enhance the performance of PEDOT:PSS in organic electronic devices.  相似文献   
74.
摘要 目的:探讨不同浓度罗哌卡因腰硬联合麻醉用于人工髋关节置换手术对患者麻醉效果和术后运动功能的影响。方法:2017年2月至2019年12月选择在本院进行人工髋关节置换手术的患者84例,根据随机数字表法把患者分为观察组与对照组各42例。两组都给予腰硬联合麻醉,对照组采用常规浓度0.5 %罗哌卡因麻醉观察组采用低浓度0.375 %罗哌卡因麻醉,记录患者麻醉效果和术后运动功能变化情况。结果:观察组的麻醉持续时间、运动恢复时间和感觉运动时间都显著短于对照组(P<0.05)。观察组麻醉后10 min、30 min、60 min的Bromage评分都低于对照组(P<0.05)。观察组术后7 d的低血压、恶心呕吐、头晕头痛、尿潴留等不良反应发生率为7.1 %,显著低于对照组的19.0 %(P<0.05)。两组所有患者在术后2 h、术后4 h、术后24 h的呼吸、心率均在正常范围内波动,组间与组内对比都无统计学意义(P>0.05)。结论:低浓度罗哌卡因腰硬联合麻醉用于人工髋关节置换手术能改善患者的麻醉效果和运动功能,提高麻醉效果,并不影响患者的生命体征,且能减少术后不良反应的发生。  相似文献   
75.
To detect the genomic constitutions and investigate the evolutionary relationships between Campeiostachys Drobov and Elymus L. species, we have cloned and analyzed 271 5S nuclear ribosomal DNA sequences from 27 accessions of these species, mostly of Chinese origin. We identified Long H1, Short S1, and Long Y1 unit classes in nine Campeiostachys or Elymus species. The identification of the three orthologous unit classes was confirmed by the neighbor‐joining tree of each unit class from PAUP and the phylogeny tree of three unit classes from MrBayes. The results suggested that these Elymus species comprise StYH haplomes and should be included in Campeiostachys. The phylogeny tree showed a clear separation between the S1 unit class and Y1 unit class. However, Y1 unit class sequences formed a sister clade to the S1 unit class, implying that although the St and Y haplomes might have some affinity, they are distinct from one another. The phylogeny tree also indicated that the five species in sect. Turczaninovia (C. dahurica var. cylindrica, C. dahurica var. dahurica, C. dahurica var. tangutorum, E. purpuraristatus, and E. dahuricus Turcz. ex Griseb. var. violeus C. P. Wang & H. L. Yang) might share a more recent common ancestor, whereas the four species in sect. Elymus (C. nutans, E. breviaristatus (Keng) Keng ex Keng f., E. sinosubmuticus (Keng) Keng f., and E. atratus (Nevski) Hand.‐Mazz.) share a close relationship. By identifying only one type of unit class for each haplome, we propose that the 5S nuclear ribosomal DNA sequences of species within Campeiostachys might have undergone haplome‐specific concerted evolution.  相似文献   
76.
FK506‐sensitive proline rotamases (FPRs), also known as FK506‐binding proteins (FKBPs), can mediate immunosuppressive drug resistance in budding yeast but their physiological roles in filamentous fungi remain opaque. Here, we report that three FPRs (cytosolic/nuclear 12.15‐kD Fpr1, membrane‐associated 14.78‐kD Fpr2 and nuclear 50.43‐kD Fpr3) are all equally essential for cellular Ca2+ homeostasis and contribute significantly to calcineurin activity at different levels in the insect‐pathogenic fungus Beauveria bassiana although the deletion of fpr1 alone conferred resistance to FK506. Radial growth, conidiation, conidial viability and virulence were less compromised in the absence of fpr1 or fpr2 than in the absence of fpr3, which abolished almost all growth on scant media and reduced growth moderately on rich media. The Δfpr3 mutant was more sensitive to Na+, K+, Mn2+, Ca2+, Cu2+, metal chelate, heat shock and UVB irradiation than was Δfpr2 while both mutants were equally sensitive to Zn2+, Mg2+, Fe2+, H2O2 and cell wall‐perturbing agents. In contrast, the Δfpr1 mutant was less sensitive to fewer stress cues. Most of 32 examined genes involved in DNA damage repair, Na+/K+ detoxification or osmotolerance and Ca2+ homeostasis were downregulated sharply in Δfpr2 and Δfpr3 but rarely so affected in Δfpr1, coinciding well with their phenotypic changes. These findings uncover important, but differential, roles of three FPRs in the fungal adaptation to insect host and environment and provide novel insight into their essential roles in calcium signalling pathway.  相似文献   
77.
Understanding how biodiversity and interaction networks change across environmental gradients is a major challenge in ecology. We integrated metacommunity and metanetwork perspectives to test species’ functional roles in bird–plant frugivory interactions in a fragmented forest landscape in Southwest China, with consequences for seed dispersal. Availability of fruit resources both on and under trees created vertical feeding stratification for frugivorous birds. Bird–plant interactions involving birds feeding only on‐the‐tree or both on and under‐the‐tree (shared) had a higher centrality and contributed more to metanetwork organisation than interactions involving birds feeding only under‐the‐tree. Moreover, bird–plant interactions associated with large‐seeded plants disproportionately contributed to metanetwork organisation and centrality. Consequently, on‐the‐tree and shared birds contributed more to metanetwork organisation whereas under‐the‐tree birds were more involved in local processes. We would expect that species’ roles in the metanetwork will translate into different conservation values for maintaining functioning of seed‐dispersal networks.  相似文献   
78.
Grain size and plant architecture are critical factors determining crop productivity. Here, we performed gene editing of the MIR396 gene family in rice and found that MIR396e and MIR396f are two important regulators of grain size and plant architecture. mir396ef mutations can increase grain yield by increasing grain size. In addition, mir396ef mutations resulted in an altered plant architecture, with lengthened leaves but shortened internodes, especially the uppermost internode. Our research suggests that mir396ef mutations promote leaf elongation by increasing the level of a gibberellin (GA) precursor, mevalonic acid, which subsequently promotes GA biosynthesis. However, internode elongation in mir396ef mutants appears to be suppressed via reduced CYP96B4 expression but not via the GA pathway. This research provides candidate gene‐editing targets to breed elite rice varieties.  相似文献   
79.
The progression of diabetic cardiomyopathy is related to cardiomyocyte dysfunction and apoptosis. Our previous studies showed that asporin (ASPN) was significantly increased in the myocardium of db/db mice through proteomics, and grape seed procyanidin B2 (GSPB2) significantly inhibited the expression of ASPN in the heart of db/db mice. We report here that ASPN played a critical role in glycated low‐density lipoproteins (gly‐LDL) induced‐cardiomyocyte apoptosis. We found that gly‐LDL upregulated ASPN expression. ASPN increased H9C2 cardiomyocyte apoptosis with down‐regulation of Bcl‐2, upregulation of transforming growth factor‐β1, Bax, collagen III, fibronectin, and phosphorylation of smad2 and smad3. However, GSPB2 treatment reversed ASPN‐induced impairments in H9C2 cardiomyocytes. These results provide evidence for the cardioprotective action of GSPB2 against ASPN injury, and thus suggest a new target for fighting against diabetic cardiomyopathy.  相似文献   
80.
Two types of cecidomyiid leaf galls, cup‐shaped and umbrella‐shaped, occur on Litsea acuminata (Lauraceae) in Taiwan. Based on the concept of gall shapes as “extended phenotypes” of gall inducers, these two types could be induced by different gall midge species. However, galls with intermediate shapes between the two types were recently discovered, which implies that possible genetic exchanges occur between the gall inducers of both types. To clarify the taxonomic status of gall midges responsible for the two types of galls on L. acuminata, we undertook taxonomic, molecular phylogenetic and ecological studies. Our findings show that the two gall types are induced by the same Bruggmanniella species and the species is new to science. We describe the species forming this range of galls as Bruggmanniella litseae sp. n. , and compare their geographical distribution, galling position and morphometry. Based on our results, a possible evolutionary scenario of B. litseae sp. n. is discussed.  相似文献   
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