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891.
Jiliang Xu Xiaohui Zhang Zhengwang Zhang Guangmei Zheng Xiangfeng Ruan Keyin Zhang Bo Xi 《生物学前沿》2006,1(2):174-181
Home range and habitat use of male Reeves’s pheasant (Syrmaticus reevesii) were studied during winter of 2001~2002 and 2002~2003 in the Dongzhai National Nature Reserve, Henan Province. Results from five individuals of Reeves’s pheasant with over 30 relocations, indicated that the average size of home range was 10.03 ± 1.17 hm2 by Minimum Convex Polygon method, 8.60 ± 0.35 hm2 by 90% Harmonic Mean Transformation method, and 9.50 ± 1.90 hm2 by 95% Fixed Kernel method. It was observed that the winter range is smaller than that in the breeding season. The mean core area of the home range was found to be 1.88 ± 0.37 hm2. Although the habitat composition of the core area varied greatly for individuals, a large part of the habitats used were composed of confier and broadleaf mixed forests, masson pine forests, fir forests, and shrubs. Habitat use within the study area was non-random, while habitats within home ranges were randomly used. Habitat use was dictated by tree diameter at breast height, shrub height and coverage at 2.0 m. The proximity between forests and shrubs were also found to be important in providing refuge for the birds during winter. Recommendations for conservation management include protecting the existing habitats in Dongzhai National Nature Reserve, increasing suitable habitat for Reeves’s Pheasant through artificial plantations (e.g. firs), and restoring some parts of the large shrub area into forests. 相似文献
892.
The locations of the 3' ends of RNAs in rat ribosome were studied by a fluorescence-labeling method combined with high hydrostatic pressure and agarose electrophoresis. Under physiological conditions, only the 3' ends of 28 S and 5.8 S RNA in 80 S ribosome could be labeled with a high sensitive fluorescent probe - fluorescein 5-thiosemicarbazide (FTSC), indicating that the 3' termini of 28 S and 5.8 S RNA were located on or near the surface of 80 S ribosome. The 3' terminus of 5 S RNA could be attacked by FTSC only in the case of the dissociation of the 80 S ribosome into two subunits induced by high salt concentration (1 M KCl) or at high hydrostatic pressure, showing that the 3' end of 5 S RNA was located on the interface of two subunits. However, no fluorescence-labeled 18 S RNA could be detected under all the conditions studied, suggesting that the 3' end of 18 S RNA was either located deeply inside ribosome or on the surface but protected by proteins. It was interesting to note that modifications of the 3' ends of ribosomal RNAs including oxidation with NaIO4, reduction with KBH4 and labeling with fluorescent probe did not destroy the translation activity of ribosome, indicating that the 3' ends of RNAs were not involved in the translation activity of ribosome. 相似文献
893.
Lijuan Xing Guangsen Shi Haibin Ruan Xiwen Gu Zhiwei Liu Xi Wu Xiang Gao Ying Xu 《The EMBO journal》2010,29(8):1389-1400
The circadian clock has a central role in physiological adaption and anticipation of day/night changes. In a genetic screen for novel regulators of circadian rhythms, we found that mice lacking MAGED1 (Melanoma Antigen Family D1) exhibit a shortened period and altered rest–activity bouts. These circadian phenotypes are proposed to be caused by a direct effect on the core molecular clock network that reduces the robustness of the circadian clock. We provide in vitro and in vivo evidence indicating that MAGED1 binds to RORα to bring about positive and negative effects on core clock genes of Bmal1, Rev‐erbα and E4bp4 expression through the Rev‐Erbα/ROR responsive elements (RORE). Maged1 is a non‐rhythmic gene that, by binding RORα in non‐circadian way, enhances rhythmic input and buffers the circadian system from irrelevant, perturbing stimuli or noise. We have thus identified and defined a novel circadian regulator, Maged1, which is indispensable for the robustness of the circadian clock to better serve the organism. 相似文献
894.
Weiwei Lu Yirui Zhang Yixian Yao Yuying Wu Han Y. H. Chen Hailin Zhang Jia Yu Caiqin Shen Qi Liu Honghua Ruan 《Phyton》2020,89(1):13-26
The priming effect (PE) induced by biochar provides a basis for
evaluating its carbon (C) sequestration potential in soils. A 60 days’ laboratory
incubation was conducted, which involved the amendment of biochar (1% of soil
mass) produced from rice straw at 300ºC (B300) and 500ºC (B500) to young (Y)
and old (O) poplar plantation soils, with the aim of studying the responses of
biochar-induced PEs to poplar plantation ages. This incubation included six
treatments: Y + CK (control), Y + B300, Y + B500, O + CK, O + B300, and O +
B500. Carbon dioxide (CO2) emissions were significantly increased (p < 0.05) in
the B300 amended soils, while it was decreased in the B500 amended soils
compared to the CK. The primed CO2 emissions were 2.35 times higher in the Y
+ B300 than the O + B300 treatments, which was measured to be 18.6 and 5.56
mg C·kg-1 with relative PEs of 12.4% and 3.35%, respectively. However, there
was little difference between the primed CO2 emissions in Y + B500 and O +
B500 treatments, which were measured to be -24.9 and -29.6 mg·C·kg-1 with
relative PEs of -16.6% and -17.8%, respectively. Dissolved organic carbon
(DOC) was significantly lower in the young poplar plantation soil than that in the
old poplar plantation soil regardless of biochar amendment throughout the
incubation, indicating greater C-limit of soil microorganisms in the young poplar
plantation soil. Using 13C isotope tracing, neither B300 nor B500 decreased
native soil-derived DOC, which indicated that the negative B500-induced PEs
were not due to a reduction in the availability of native soil-derived C. In
conclusion, the response of biochar-induced PEs to poplar plantation age
depends on biochar types while soil available C indirectly affects biocharinduced PEs. Further studies should focus on how the interactive effects between
soil C availability and microbial community impacts biochar-induced PEs. 相似文献
895.
Zhiyan Ruan Minhua Liang Xiangliang Deng Manxiang Lai Ling Shang Xinguo Su 《Cell biology international》2020,44(1):306-316
Fatty liver disease is a disease manifested with excessive alcohol intake and obese. Importantly, hydrogen sulfide (H2S) has been revealed to participate in the progression of fatty liver; however, the underlying mechanism has not been clearly elucidated yet. In this study, we aimed to investigate the effects of exogenous H2S on fatty liver ischemia–reperfusion injury (IRI) through mediating class A scavenger receptor (SRA) pathway in rats. By determining endoplasmic reticulum stress (ERS)‐related factors, autophagy markers and apoptosis‐related factors in liver tissue and liver function, levels of oxidative stress, inflammatory factors, and hepatocyte apoptosis, the effects of H2S on IRI‐induced autophagy, oxidative stress, and inflammation were all examined in rat model of fatty liver IRI. Results from obtained data showed that H2S decreased the expression of SRA, Grp78, PERK, CHOP, and Caspase‐3, and increased that of LC3‐II/LC3‐I, in addition to alleviating the pathological changes of liver and reducing the levels of ALT, AST, LDH TBARS, and MDA. Moreover, H2S decreased the levels of oxidative stress, the expression of pro‐inflammatory factors including tumor necrosis factor α, interleukin 1, and interleukin 6, and the apoptosis of hepatocytes. Our findings suggested exogenous H2S could reduce ERS by mediating the SRA pathway and protect liver function by inducing autophagy, and protect against IRI by reducing oxidative stress and inflammation. 相似文献
896.
897.
Akbar Sehrish Yao Wei Yu Kai Qin Lifang Ruan Miaohong Powell Charles A. Chen Baoshan Zhang Muqing 《Photosynthesis research》2021,150(1-3):279-294
Photosynthesis Research - Sugarcane mosaic virus (SCMV), belonging to genus Potyvirus, family Potyviridae, is a severe pathogen of several agricultural important crops, mainly sugarcane. Due to... 相似文献
898.
Ruan Ping Yang Chun Su Jianjia Cao Ji Ou Chao Luo Chengpiao Tang Yanping Wang Qi Yang Fang Shi Junlin Lu Xiaoxu Zhu Linqun Qin Hong Sun Wen Lao Yuanzhi Li Yuan 《Virology journal》2013,10(1):1-11
Herpes simplex virus type-1(HSV-1) and HSV-2 are important human pathogens that cause significant ocular and urogenital complications, respectively. We have previously shown that HSV-1 virions lacking glycoprotein K (gK) are unable to enter into neurons via synaptic axonal membranes and be transported in either retrograde or anterograde manner. Here, we tested the ability of HSV-1 (F) gK-null to protect against lethal challenge with either highly virulent ocular HSV-1 (McKrae strain), or genital HSV-2 (G strain). The gK-null virus vaccine efficiently protected mice against lethal vaginal infection with either HSV-1(McKrae) or HSV-2 (G). Female mice were immunized via a single intramuscular injection with 106 PFU of the gK-null virus. Immunized mice were treated with Depo-Provera fourteen days after vaccination and were challenged via the vaginal route one week later. Ninety percent of mice vaccinated with the gK-null virus survived HSV-1 (McKrae) challenge, while 70% of these mice survived after HSV-2 (G) challenge. Moreover, all vaccinated mice exhibited substantially reduced disease symptoms irrespective of HSV-1 or HSV-2 challenge as compared to the mock vaccinated challenge group. T-cell memory immune responses to specific glycoprotein B (gB) and glycoprotein D (gD) peptide epitopes were detectable at 7 months post vaccination. These results suggest that the highly attenuated, non-neurotropic gK-null virus may be used as an effective vaccine to protect against both virulent HSV-1 and HSV-2 genital infections and induce lasting immune responses. 相似文献
899.
900.
Li Tao Fangtian Fan Yuping Liu Weidong Li Lei Zhang Junshan Ruan Cunsi Shen Xiaobo Sheng Zhijie Zhu Aiyun Wang Wenxing Chen Shile Huang Yin Lu 《PloS one》2013,8(11)
Xanthatin, a sesquiterpene lactone purified from Xanthium strumarium L., possesses prominent anticancer activity. We found that disruption of GSK3β activity was essential for xanthatin to exert its anticancer properties in non-small cell lung cancer (NSCLC), concurrent with preferable suppression of constitutive activation of STAT3. Interestingly, inactivation of the two signals are two mutually exclusive events in xanthatin-induced cell death. Moreover, we surprisingly found that exposure of xanthatin failed to trigger the presumable side effect of canonical Wnt/β-Catenin followed by GSK3β inactivation. We further observed that the downregulation of STAT3 was required for xanthatin to fine-tune the risk. Thus, the discovery of xanthatin, which has ability to simultaneously orchestrate two independent signaling cascades, may have important implications for screening promising drugs in cancer therapies. 相似文献