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Progress in Natural Science:Materials International 2007年第10期17卷 1166-1171页

作者： Xu Yufeng, Zhou Gongke, Li Yiqin and Liu Jinyuan(Laboratory of Molecular Biology and Protein Science Laboratory of the Ministry of Education, Department of Biological Sciences and Biotechnology, Tsinghua University, Beijing 100084, China) Laboratory of Molecular Biology and Protein Science Laboratory Department of Biological Sciences and Biotechnology Tsinghua University Beijing 100084 China

Northern blot and functional complementation assay were employed to analyze the effects of zinc on expression of ten rice metallothionein genes (OsMT-Is) in rice seedlings and the growth of yeast cells transformed with OsMT-Is. Northern blot revealed that in shoots of the rice seedlings treated with different Zn2+concentrations, expression of most members of OsMT-I family was increased, except the type 4 OsMT-Is (OsMT-I-4a, 4b and 4c). In roots, Zn2+significantly increased the transcription of OsMT-I-1b and OsMT-I-2c, but reduced the trascription of OsMT-I-1a and OsMT-I-3a. When these ten cDNAs were heterologously expressed in zinc sensitive yeast mutant, all transgenic yeasts showed increased tolerance.to Zn2+, and zinc accumulation in these yeast cells also increased. These indicated that OsMT-I family members might respond to extra Zn2+, and they could enhance Zn2+ tolerance.of cells by direct binding Zn2+.

关键词： rice metallothionein induced expression Zn2+ tolerance.

Salt tolerance.of transgenic rice (Oryza sativa L.) with mtlD gene and gutD gene

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Chinese Science Bulletin 2000年第18期45卷 1685-1690页

作者： WANG Huizhong HUANG Danian LU Ruifang LIU Junjun QIAN Qian PENG Xuexian Department of Biology Hangzhou Teacher’s CollegeHangzhou 310012China China National Rice Research Institute Hangzhou 310006China Institute of Microbiology Chinese Academy of SciencesBeijing 100080China

Southern blot analysis indicated that mtID gene (encoding mannitol-1 -phosphate dehydrogenase) and gutD gene (encoding glucitol-6-phosphate dehydrogenase) had been integrated into the rice genome mediated by Agrobacterium tumefaciens LBA4404(pBIGM). The expression of the above two genes in transgenic rice plants was demonstrated by Northern blot analysis and enzymatic activity assay. Analysis of sugar alcohol showed that transgenic rice plants could produce and accumulate mannitol and sorbitol. The salt tolerance.of transgenic plants was much higher than that of their controls.

关键词： Oryza sativa L. Agrobacterium tumefaciens D-mannitol-1-phosphate dehydrogenase D-glucitol-6-phosphate dehydrogenase salt tolerance.

ACCELERATED SYNTHESIS AND RELEASE OF ANGIOTENSIN II IN THE RAT BRAIN DURING ELECTROACUPUNCTURE tolerance

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Science China Chemistry 1990年第6期33卷 686-693页

作者：王克威韩济生 Department of Physiology Beijing Medical University Beijing 100083 PRC

Behaviouzal studies suggested that cerebral angiotensin Ⅱ (AⅡ) plays an important role in the development of tolerance.to electroacupuncture (EA) analgesia. Observations made in this study revealed an increase in AⅡ immunoreactivity (AⅡ-it) in both CSF and brain as well as an increase in the cerebral content of AⅠ-ir in rats rendered tolerant to EA. The extracts of brain from rats receiving EA for 1h and 3h were subjected to gel filtration and the elution profile was compared with that of normal brain extract. There was a marked right shift of the AⅡ peak from the large molecule precursor to the small molecule AⅡ-*** latter peak showed the same retention time in HPLC system as that of AⅡ. The results suggest that the acceleration of the synthesis and release of AⅡ during s Iong-term EA stimulation might constitute one of the mechanisms for EA tolerance.

关键词： angiotensin Ⅱ electroacupuncture analgesia tolerance.

Liver natural killer cells： subsets and roles in liver immunity

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Cellular & Molecular Immunology 2016年第3期13卷 328-336页

作者： Hui Peng Eddie Wisse Zhigang Tian Institute of Immunology and The CAS Key Laboratory of Innate Immunity and Chronic Disease School of Life Sciences and Medical Center University of Science and Technology of China Hefei Anhui China Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases State Key Laboratory for Diagnosis and Treatment of Infectious Diseases First Affiliated Hospital College of Medicine Zhejiang University Hangzhou Zhejiang China Maastricht Multimodal Molecular Imaging Institute Division of Nanoscopy Universiteitssingel 50 Maastricht The Netherlands

The liver represents a frontline immune organ that is constantly exposed to a variety of gut-derived antigens as a result of its unique location and blood supply, With a predominant role in innate immunity, the liver is enriched with various innate immune cells, among which natural killer （NK） cells play important roles in host defense and in maintaining immune balance, Hepatic NK cells were first described as ＇pit cells＇ in the rat liver in the 1970s, Recent studies of NK cells in mouse and human livers have shown that two distinct NK cell subsets, liver-resident NK cells and conventional NK （cNK） cells, are present in this organ, Here, we review liver NK cell subsets in different species, revisiting rat hepatic pit ceils and highlighting recent progress related to resident NK cells in mouse and human livers, and also discuss the dual roles of NK cells in liver immunity,

关键词： conventional NK cell liver liver-resident NK cell pit cell tolerance.

Constrained Bézier curves' best multi-degree reduction in the L2-norm

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Progress in Natural Science:Materials International 2005年第9期15卷 843-850页

作者： ZHANG Renjiang 1,2 ** and WANG Guojin1(1. Institute of Computer Images and Graphics, Zhejiang University, Hangzhou 310027, China 2. China Institute of Metrology, Zhejiang, Hangzhou 310034, China) Institute of Computer Images and Graphics Zhejiang University Hangzhou 310027 China. State Key Laboratory of CAD&CG Zhejiang University Hangzhou 310027 China. China Institute of Metrology Zhejiang Hangzhou 310034 China

In computer aided geometric design, the degree reduction of the parameter curve is a key technique in data exchange and data compression. The various existing methods of degree reduction cannot decide whether the degree reduction curve satisfying the given tolerance.exists beforehand, cannot give approximation of the best multi-degree reduction, or cannot provide explicit expression and error formula of the degree reduction curve. In this paper, we propose an entirely new method, which can hurdle the above flaws completely. For a given Bézier curve of degree n, we can easily decide whether a Bézier reduction curve of degree m exists, which has equal derivatives with the given curve up to （r-1）-th and （s-1）-th orders （r,s≤m） respectively at the endpoints, so the approximating error is less than the given tolerance.ε in the L2-norm. If the curve exists, the explicit expression can be given.

关键词： computer aided design Bézier curve degree reduction L2-norm tolerance.

Do females use their sexual status to gain resource access？ Investigating food-for-sex in wolves and dogs

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Current Zoology 2017年第3期63卷 323-330页

作者： Rachel DALE Sarah MARSHALL-PESCINI Friederike RANGE Comparative Cognition Messerli Research Institute University of Veterinary Medicine Medical University of Vienna University of Vienna Vienna Austria Wolf Science Center Ernstbrunn Austria

While food sharing among related individuals can be explained by kin selection, food sharing be- tween unrelated individuals has been more of an evolutionary puzzle. The food-for-sex hypothesis provides an explanation for the occurrence of food sharing among nonkin. However, little is known about the socio-ecological factors that can promote such a commodity exchange. A species mating system is a factor potentially influencing food-for-sex patterns of behavior. Here, we compared wolves, which form pair-bonds, with dogs, which are typically promiscuous in freeranging contexts, to investigate the effect of reproductive stages on the behavior around a food source in 2 different contexts. Furthermore, we considered the roles of both the males and the fe- males in the potential food-for-sex exchange. Results indicate that in both species and for both sexes the breeding period promotes decreased aggression. Additionally, females were more per- sistent in their attempts to access the food and were able to monopolize the resource more when in heat as compared to outside the breeding period. Finally, in dogs, but not wolves, females spent more time in proximity to the male＇s bone and had a shorter latency to start eating it when in heat. Overall, this study demonstrates that the food-for-sex hypothesis plays a part in intersexual food sharing in canids, and highlights the role of females in the interaction. These effects were especially the case in dogs, suggesting a potential effect of mating system on food-for-sex responses

关键词： canid food-for-sex food sharing tolerance.

Social interactions in a solitary carnivore

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Current Zoology 2017年第4期63卷 357-362页

作者： L. Mark ELBROCH Howard QUIGLEY Panthera 8 West 40th Street 18th Floor New York NY 10018 USA

In total, 177 of 245 terrestrial carnivores are described as solitary, and much of carnivore ecology is built on the assumptions that interactions between adult solitary carnivores are rare. We employed Global Positioning System （GPS） technology and motion-triggered cameras to test predictions of land-tenure territoriality and the resource dispersion hypothesis in a territorial carnivore, the puma Puma concolor. We documented 89 independent GPS interactions, 60% of which occurred at puma kills （n=53）, 59 camera interactions, 11 （17%） of which captured courtship behaviors, and 5 other interactions （1 F-F, 3 M-F, and 1 M-M）. Mean minimum weekly contact rates were 5.5 times higher in winter, the season when elk Cervus elaphus were aggregated at lower elevations and during which puma courtship primarily occurred. In winter, contacts rates were 0.6_＋ 0.3 （standard devi- ation （SD）） interactions/week vs. 0.1 _＋ 0.1 （SD） interactions/week during summer. The preponder- ance of interactions at food sources supported the resource dispersion hypothesis, which predicts that resource fluxes can explain temporary social behaviors that do not result in any apparent benefits for the individuals involved. Conspecific tolerance.is logical when a prey is so large that the predator that killed it cannot consume it entirely, and thus, the costs of tolerating a conspecific sharing the kill are less than the potential costs associated with defending it and being injured. Puma aggregations at kills numbered as high as 9, emphasizing the need for future research on what explains tolerance.among solitary carnivores.

关键词： carnivores competition Puma concolor resource dispersion hypothesis social interactions tolerance.

AtHsfA2 modulates expression of stress responsive genes and enhances tolerance.to heat and oxidative stress in Arabidopsis

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Science China(Life Sciences) 2005年第6期48卷 540-550页

作者： LI Chunguang1,2, CHEN Qijun1, GAO Xinqi1,3, QI Bishu1, CHEN Naizhi1, XU Shouming1, CHEN Jia1 & WANG Xuechen1 1. State Key Laboratory of Plant Physiology and Biochemistry, College of Biological Sciences, China Agricultural University, Beijing 100094, China 2. Department of Industry Engineering, Zhengzhou Institute of Aeronautic Industry Management, Zhengzhou 450015, China 3. College of Life Science, Qufu Normal University, Qufu Shandong 273165, China State Key Laboratory of Plant Physiology and Biochemistry College of Biological Sciences China Agricultural University Beijing 100094 China Department of Industry Engineering Zhengzhou Institute of Aeronautic Industry Management Zhengzhou 450015 China State Key Laboratory of Plant Physiology and Biochemistry College of Biological Sciences China Agricultural University Beijing 100094 China State Key Laboratory of Plant Physiology and Biochemistry College of Biological Sciences China Agricultural University Beijing 100094 China College of Life Science Qufu Normal University Qufu Shandong 273165 China

There is increasing evidence for considerable interlinking between the responses to heat stress and oxidative stress, and recent researches suggest heat shock transcription factors (Hsfs) play an important role in linking heat shock with oxidative stress signals. In this paper, we present evidence that AtHsfA2 modulated expression of stress responsive genes and enhanced tolerance.to heat and oxidative stress in Arabidopsis. Using Northern blot and quantitative RT-PCR analysis, we demonstrated that the expression of AtHsfA2 was induced by not only HS but also oxidative stress. By functional analysis of AtHsfA2 knockout mutants and AtHsfA2 overexpressing transgenic plants, we also demonstrated that the mutants displayed reduced the basal and acquired thermotolerance.as well as oxidative stress tolerance.but the overexpression lines displayed increased tolerance.to these stress. The phenotypes correlated with the expres-sion of some Hsps and APX1, ion leakage, H2O2 level and degree of oxidative injuries. These results showed that, by modulated expression of stress responsive genes, AtHsfA2 enhanced tolerance.to heat and oxidative stress in Arabidopsis. So we suggest that AtHsfA2 plays an im-portant role in linking heat shock with oxidative stress signals.

关键词： heat shock transcription factor, heat stress response, oxidative stress response, tolerance.

RESISTANCE OF THE NEUROMUSCULAR JUNCTION OF THE SNAKE TO THE BLOCKING ACTION OF BOTULINUM TOXIN TYPE A

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Chinese Science Bulletin 1991年第13期36卷 1122-1125页

作者：施玉梁王文萍徐科 Shanghai Institute of Physiology Academia Sinica Shanghai 200031 PRC

As the most potent natural poison, botulinum toxin (BoTX) blocks the cholinergic synaptic transmission in skeletal muscles selectively by interfering in the acetylcholine release from motor nerve terminals and results... 详细信息

关键词： botulinum toxin toosendanin snake neuromuscular junction tolerance.

Expression of betaine aldehyde dehydrogenase gene and salinity tolerance.in rice transgenic plants

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Science China(Life Sciences) 1997年第5期40卷 496-501页

作者：郭岩张莉肖岗曹守云谷冬梅田文忠陈受宜 Institute of Genetics Chinese Academy of Sciences Beijing 100101 China

Betaine as one of osmolytes plays an important role in osmoregulation of most high plants. Betaine aldehyde dehydrogenase C BADH) is the second enzyme involved in betaine biosynthesis. The BADH gene from a halophite, Atriplex hortensis, was transformed into rice cultivars by bombarment method. Totally 192 transgenic rice plants were obtained and most of them had higher salt tolerance.than controls. Among transgenic plants transplanted in the saline pool containing 0.5% NaCl in a greenhouse, 22 survived, 13 of which set seeds, and the frequency of seed setting was very low, only 10% . But the controls could not grow under the same condition. The results of BADH ac-tivity assay and Northern blot showed that the BADH gene was integrated into chromosomes of transgenic plants and expressed.

关键词： BADH gene transgenic rice molecular assay high salinity tolerance.