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991.
目的:探讨T-piece复苏器在产房中对早产儿复苏中的应用效果。方法:选择2011年1月至2016年12月在本院产科出生的早产儿(胎龄28~37周)62例,随机分为对照组与观察组,各31例,对照组患儿给予自动充气式复苏囊正压人工通气,观察组患儿给予T组合复苏器正压人工通气,比较两组患儿1、5、10 min Apgar评分、肺气漏发生率,以及缺氧缺血性脑病、支气管肺发育不良、坏死性小肠结肠炎、动脉导管未闭、高胆红素血症率。结果:两组患儿胎龄、性别、分娩方式、出生体重、出生后1、5、10 min Apgar评分等方面差异均无统计学意义(P0.05)。与对照组相比,观察组气漏发生率降低,差异有统计学意义(P0.05)。两组患儿缺氧缺血性脑病、支气管肺发育不良、坏死性小肠结肠炎、动脉导管未闭、高胆红素血症率差异无统计学意义(P0.05)。结论:T-piece复苏器在产房中早产儿窒息复苏中的应用效果显著,具有操作简单、效率高等优点,两组复苏成功率差别不大,但T-piece复苏器能可有效减少肺气漏的发生,进而降低新生儿的病死率。  相似文献   
992.
海南岛位于我国南部, 地处热带北缘, 其独特的岛屿气候环境孕育了丰富的生物资源, 为我国生物多样性热点地区之一。为探究岛内的翼手目物种多样性状况, 本研究组使用雾网、蝙蝠竖琴网等工具, 于2002年至2016年先后对海南岛进行了15次翼手目多样性调查, 并根据其外形与头骨特征及系统发育学方法进行标本鉴定。共获取了1,025号标本, 隶属5科15属31种, 其中2016年12月21日在海南琼中捕获的艾氏管鼻蝠(Murina eleryi)为海南岛蝙蝠分布新记录。结合前人调查及发表结果统计, 岛内共有翼手类8科20属41种。同时基于本调查采集位点和前人调查位置信息(共计363个位点), 结合WorldClim 32种气候数据, 运用最大熵模型(MaxEnt)对海南岛翼手目物种的分布进行预测, 结果显示五指山、吊罗山、鹦哥岭、尖峰岭及海口火山口国家地质公园等地为翼手目物种多样性较丰富的区域, 而三亚、澄迈、屯昌、临高、琼海等地翼手目物种多样性较低。本研究结果为海南岛翼手目资源分布及多样性状况提供了基础资料, 也为岛内后续开展翼手目资源保护管理、蝙蝠疾病防控等提供了重要的参考依据。  相似文献   
993.
比较分析投加不同微生态制剂的海水养殖系统硝化功能建立的过程,为实际应用提供依据。利用海水素构建4个海水养殖系统,通过投加硝化细菌、光合细菌、枯草芽胞杆菌3种微生态制剂以及纤维毛球作为生物膜载体,比较分析不同养殖系统硝化功能的建立过程及硝化强度差异。投加硝化细菌+光合细菌和硝化细菌+枯草芽胞杆菌系统硝化功能建立时间分别为108 h和96 h,氨氮初始质量浓度为6 mg/L时,氨氧化强度分别为1.69 mg/(L·d)和1.36 mg/(L·d);添加纤维毛球的生物膜系统与生物絮团系统硝化功能建立时间分别为96 h和120 h,氨氮初始质量浓度为6 mg/L时,氨氧化强度分别为1.36 mg/(L·d)和0.98 mg/(L·d);投加碳源系统和对照系统硝化功能建立时间分别为84 h和96 h,氨氮初始质量浓度为6 mg/L时,氨氧化强度分别为1.18 mg/(L·d)和1.36 mg/(L·d)。硝化细菌+枯草芽胞杆菌系统硝化功能建立时间更短,但系统硝化强度低于硝化细菌+光合细菌系统;生物膜系统硝化强度高于生物絮团系统且硝化功能建立更快;添加碳源能够加快系统硝化功能建立过程,但降低了硝化细菌+枯草芽胞杆菌系统的硝化强度。  相似文献   
994.
995.
Two new C13‐polyketides, aureonitols A and B ( 1 and 2 ), along with five known compounds ( 3 – 7 ), were isolated from the solid fermentation culture of the plant endophytic fungus Chaetomium globosum from the aerial parts of Salvia miltiorrhiza. The structures and absolute configurations of 1 and 2 were determined by comprehensive spectroscopic data analysis and computed methods. Compound 5 was found to display the remarkable antimicrobial activities against four multidrug‐resistant bacteria (Enterococcus faecalis, Enterococcus faecium, Staphylococcus aureus, and Staphylococcus epidermidis) with MIC values of 3.13–6.25 μg/mL (ciprofloxacin: 0.78–1.56 μg/mL), and also against all tested fungal strains with MIC values of 3.13–25 μg/mL (ketoconazole: 0.78–12.50 μg/mL).  相似文献   
996.
Abrupt drought–flood alternation (T1) is a meteorological disaster that frequently occurs during summer in southern China and the Yangtze river basin, often causing a significant loss of rice production. In this study, the response mechanism of yield decline under abrupt drought–flood alternation stress at the panicle differentiation stage was analyzed by looking at the metabolome, proteome as well as yield and physiological and biochemical indexes. The results showed that drought and flood stress caused a decrease in the yield of rice at the panicle differentiation stage, and abrupt drought–flood alternation stress created a synergistic effect for the reduction of yield. The main reason for the decrease of yield per plant under abrupt drought–flood alternation was the decrease of seed setting rate. Compared with CK0 (no drought and no flood), the net photosynthetic rate and soluble sugar content of T1 decreased significantly and its hydrogen peroxidase, superoxide dismutase, peroxidase activity increased significantly. The identified differential metabolites and differentially expressed proteins indicated that photosynthesis metabolism, energy metabolism pathway and reactive oxygen species response have changed strongly under abrupt drought–flood alteration stress, which are factors that leads to the rice grain yield reduction.  相似文献   
997.
Understanding the ecological and evolutionary mechanisms that shape a species’ range is an important goal in evolutionary biology. Evidence indicates that mating system is an effective predictor of the global range of native species or naturalized alien plants, but the mechanisms underlying this predictability are not elaborated. Here, we develop a theoretical model to account for the ranges of plants under different mating systems based on migration‐selection processes (an idea proposed by Haldane). The model includes alternation of gametophyte and sporophyte generations in one life cycle and the dispersal of haploid pollen and diploid seeds as vectors for gene flow. We show that the interaction between selfing rates and gametophytic selection determines the role of mating system in shaping a species’ range. Selfing restricts the species’ range under gametophytic selection in nonrandom mating systems, but expands the species’ range under the absence of gametophytic selection in any mating system. Gametophytic selection slightly restricts the species’ range in random mating. Both logarithmic and logistic models of population demography yield similar conclusions in the case of fixed or evolving genetic variance. The theory also helps to explain a broader relationship between mating system and range size following biological invasion or plant naturalization.  相似文献   
998.
Achilles tendon injury is one of the challenges of sports medicine, the aetiology of which remains unknown. For a long time, estrogen receptor β (ERβ) has been known as a regulating factor of the metabolism in many connective tissues, such as bone, muscle and cartilage, but little is known about its role in tendon. Recent studies have implicated ERβ as involved in the process of tendon healing. Tendon‐derived stem cells (TDSCs) are getting more and more attention in tendon physiological and pathological process. In this study, we investigated how ERβ played a role in Achilles tendon healing. Achilles tendon injury model was established to analyse how ERβ affected on healing process in vivo. Cell proliferation assay, Western blots, qRT‐PCR and immunocytochemistry were performed to investigate the effect of ERβ on TDSCs. Here, we showed that ERβ deletion in mice resulted in inferior gross appearance, histological scores and, most importantly, increased accumulation of adipocytes during the early tendon healing which involved activation of peroxisome proliferator‐activated receptor γ (PPARγ) signalling. Furthermore, in vitro results of ours confirmed that the abnormity might be the result of abnormal TDSC adipogenic differentiation which could be partially reversed by the treatment of ERβ agonist LY3201. These data revealed a role of ERβ in Achilles tendon healing for the first time, thereby providing a new target for clinical treatment of Achilles tendon injury.  相似文献   
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