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921.
922.
综合性医院重症监护病房病原菌分离情况分析 总被引:1,自引:0,他引:1
目的探讨重症监护病房(Icu)医院内感染的临床特点及病原菌种类、分布情况,为临床合理使用抗菌药物、预防和控制医院感染提供参考和依据。方法采用前瞻性监测与回顾性调查相结合的方法,对ICU患者的临床资料进行统计分析。结果ICU病人标本中分离出病原菌593株,得出菌种分布与感染情况。结论重症监护病房医院内感染发生率高,以呼吸道感染为主,主要病原菌以革兰阴性非发酵菌为主,加强ICU患者感染的控制,可减少ICU医院内感染的发生。 相似文献
923.
Huimin Wang Feng Jiang Xiang Liu Qing Liu Yunyun Fu Ran Li Li Hou Jie Zhang Jing He Le Kang 《EMBO reports》2022,23(3)
Animal feeding, which directly affects growth and metabolism, is an important physiological process. However, the contribution of PIWI proteins and PIWI‐interacting RNAs (piRNAs) to the regulatory mechanism of animal feeding is unknown. Here, we report a novel function of Piwi and piRNAs in regulating food intake in locusts. Our study shows that the locust can serve as a representative species for determining PIWI function in insects. Knockdown of Piwi1 expression suppresses anabolic processes and reduces food consumption and body weight. The reduction in food intake by knockdown of Piwi1 expression results from decreased expression of neuropeptide NPF1 in a piRNA‐dependent manner. Mechanistically, intronic piRNAs might enhance RNA splicing of NPF1 by preventing hairpin formation at the branch point sites. These results suggest a novel nuclear PIWI/piRNA‐mediated mechanism that controls food intake in the locust nervous system. 相似文献
924.
Jun Feng Lu Meng Qing Zhu Bao Cai Xie Xiao Chen Shi Huan Liu Rui Xin Zhang Bo Xia Jiang Wei Wu 《PLoS biology》2022,20(2)
Elevated circulating levels of growth differentiation factor 15 (GDF15) have been shown to reduce food intake and lower body weight through activation of hindbrain receptor glial-derived neurotrophic factor (GDNF) receptor alpha-like (GFRAL) in rodents and nonhuman primates, thus endogenous induction of this peptide holds promise for obesity treatment. Here, through in silico drug-screening methods, we found that small molecule Camptothecin (CPT), a previously identified drug with potential antitumor activity, is a GDF15 inducer. Oral CPT administration increases circulating GDF15 levels in diet-induced obese (DIO) mice and genetic ob/ob mice, with elevated Gdf15 expression predominantly in the liver through activation of integrated stress response. In line with GDF15’s anorectic effect, CPT suppresses food intake, thereby reducing body weight, blood glucose, and hepatic fat content in obese mice. Conversely, CPT loses these beneficial effects when Gdf15 is inhibited by a neutralizing antibody or AAV8-mediated liver-specific knockdown. Similarly, CPT failed to reduce food intake and body weight in GDF15’s specific receptor GFRAL-deficient mice despite high levels of GDF15. Together, these results indicate that CPT is a promising anti-obesity agent through activation of GDF15-GFRAL pathway.Elevated circulating levels of growth differentiation factor 15 (GDF15) have been shown to reduce food intake and lower body weight in rodents and nonhuman primates. This study reveals that the small molecule Camptothecin induces endogenous GDF15, suppressing food intake and reducing body weight in obese mice, suggesting a promising candidate for anti-obesity treatment. 相似文献
925.
926.
提要准噶尔盆地西北缘玛湖凹陷风城组主要形成于碱湖环境,含有优质生烃母岩。对玛页1井风城组岩心样品的孢粉分析建立了Protohaploxypinus perfectus–Lunatisporites tersus (PT)孢粉组合。该组合包括20属29种孢粉化石。PT组合以双气囊具肋花粉占主导,蕨类孢子含量很低为特征;孢粉母体植物类群以裸子植物门种子蕨盾籽目为主,其次为松柏纲松柏目。该组合与准噶尔盆地南缘塔什库拉组上部至乌拉泊组的Crustaesporites–Protohaploxypinus–Hamiapollenites孢粉组合可以对比,均以双气囊具肋花粉为主要特征,又同时出现重要的属种Gardenasporites bilabiatus,Triangulisaccites boleensis和Hamiapollenites saccatus。孢粉地层学和同位素年代学资料表明,玛页1井风城组PT组合的时代很可能属于石炭纪宾夕法尼亚亚纪卡西莫夫期至二叠纪乌拉尔世阿瑟尔期,玛湖凹陷区整个风城组沉积时代晚于宾夕法尼亚亚纪巴什基尔期,其上部可能包含部分乌拉尔世阿瑟尔期沉积。风城组黑色页岩中... 相似文献
927.
Xin Li Chao Pan Zhicheng Liu Peng Sun Xiaoting Hua Erling Feng Yunsong Yu Jun Wu Li Zhu Hengliang Wang 《Microbial biotechnology》2022,15(2):703-716
Acinetobacter baumannii poses a serious threat to human health, mainly because of its widespread distribution and severe drug resistance. However, no licensed vaccines exist for this pathogen. In this study, we created a conjugate vaccine against A. baumannii by introducing an O-linked glycosylation system into the host strain. After demonstrating the ability of the vaccine to elicit Th1 and Th2 immune responses and observing its good safety in mouse a model, the strong in vitro bactericidal activity and prophylactic effects of the conjugate vaccine against infection were further demonstrated by evaluating post-infection tissue bacterial loads, observing suppressed serum pro-inflammatory cytokine levels. Additionally, the broad protection from the vaccine was further proved via lethal challenge with A. baumannii. Overall, these results indicated that the conjugate vaccine could elicit an efficient immune response and provide good protection against A. baumannii infection in murine sepsis models. Thus, the conjugate vaccine can be considered as a promising candidate vaccine for preventing A. baumannii infection. 相似文献
928.
929.
930.
Shouyang Song Zhen Yu Yajing You Chenxi Liu Xiaoyu Xie Huanran Lv Feng Xiao Qiang Zhu Chengyong Qin 《Cell death & disease》2022,13(4)
The receptor tyrosine kinases (RTKs) family is well-recognized as vital targets for the treatment of hepatocarcinoma cancer (HCC) clinically, whereas the survival benefit of target therapy sorafenib is not satisfactory for liver cancer patients due to metastasis. EGFR and MET are two molecules of the RTK family that were related to the survival time of liver cancer patients and resistance to targeted therapy in clinical reports. However, the mechanism and clinical therapeutic value of EGFR/MET in HCC metastasis are still not completely clarified. The study confirmed that EGFR/MET was highly expressed in HCC cells and tissues and the phosphorylation was stable after metastasis. The expression of EGFR/MET was up-regulated in circulating tumor microemboli (CTM) to accelerate IL-8 production and resistance to the lethal effect of leukocytes. Meanwhile, highly expressed EGFR/MET effectively regulated the Ras/MAPK pathway and stabilized suspended HCC cells by facilitating proliferation and inhibiting apoptosis. Moreover, EGFR/MET promoted phosphorylation of hetero-RTKs, which was dependent on high-energy phosphoric acid compounds rather than their direct interactions. In conclusion, highly expressed EGFR/MET could be used in CTM identification and suitable for preventing metastasis of HCC in clinical practice.Subject terms: Liver cancer, Metastasis 相似文献