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核酸酶基因LoENDONUCLEASE1在东方百合花朵衰老过程中的功能分析 被引量:1
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作者 李蕊蕊 刘玉杰 +4 位作者 许鑫彤 刘熠 何颖姣 王彩云 罗靖 《华中农业大学学报》 CAS CSCD 北大核心 2024年第1期157-165,共9页
为明确百合(Lilium spp.)花朵衰老发生的分子机制,在东方百合‘西伯利亚’(Lilium oriental hybrid‘Siberia’)花被片中克隆了一个衰老相关基因LoENDONUCLEASE 1(SAG10),利用qRT-PCR进行基因表达分析,并通过农杆菌介导的拟南芥稳定表... 为明确百合(Lilium spp.)花朵衰老发生的分子机制,在东方百合‘西伯利亚’(Lilium oriental hybrid‘Siberia’)花被片中克隆了一个衰老相关基因LoENDONUCLEASE 1(SAG10),利用qRT-PCR进行基因表达分析,并通过农杆菌介导的拟南芥稳定表达系统和百合花被片瞬时表达体系验证LoENDONUCLEASE 1基因功能。结果显示,LoENDONUCLEASE 1基因开放阅读框(ORF)为921 bp,编码306个氨基酸;LoENDONU⁃CLEASE 1在百合花朵和叶片的衰老过程中特异表达,且受到脱落酸和水杨酸的诱导;拟南芥过表达LoENDO⁃NUCLEASE 1株系中叶片叶绿素含量显著低于对照株系,百合花被片中瞬时过表达LoENDONUCLEASE 1基因加速了百合花被片的衰老,且过表达花被片中丙二醛和离子渗透率含量显著高于对照。结果表明,LoEN⁃DONUCLEASE 1具有促进花朵和叶片衰老的功能。 展开更多
关键词 百合 鲜切花 花朵衰老 衰老相关基因 核酸酶 过表达
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Detection of Phaeocystis globosa using sandwich hybridization integrated with nuclease protection assay(NPA-SH) 被引量:10
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作者 Zhen Yu Mi Tiezhu Yu Zhigang 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2008年第12期1481-1486,共6页
Phaeocystis globosa Scherffel is one of the common harmful algae species in coastal waters of the southeastern China.In this study,sandwich hybridization integrated with nuclease protection assay(NPA-SH)was used to qu... Phaeocystis globosa Scherffel is one of the common harmful algae species in coastal waters of the southeastern China.In this study,sandwich hybridization integrated with nuclease protection assay(NPA-SH)was used to qualitatively and quantitatively detect P. globosa.Results showed that this method had good applicability and validity in analyzing the samples from laboratory cultures and from fields.The linear regression equation for P.globosa was obtained,and the lowest detection number of cells was 1.8×104 c... 展开更多
关键词 harmful algae blooms Phaeocystis globosa Scherffel sandwich hybridization integrated with nuclease protection assay (NPA-SH)
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Role of MMP-2 and MMP-9 and their natural inhibitors in liver fibrosis, chronic pancreatitis and non-specific inflammatory bowel diseases 被引量:16
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作者 Jacek Kurzepa Agnieszka M?dro +4 位作者 Gra?yna Czechowska Joanna Kurzepa Krzysztof Celiński Weronika Kazmierak Maria S?omka 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS 2014年第6期570-579,共10页
BACKGROUND: There is a growing evidence that matrix metalloproteinase (MMP)-2 and MMP-9 (gelatinases) play an important role in the pathogenesis of numerous disorders, especially with inflammatory etiology and ex... BACKGROUND: There is a growing evidence that matrix metalloproteinase (MMP)-2 and MMP-9 (gelatinases) play an important role in the pathogenesis of numerous disorders, especially with inflammatory etiology and extracellular matrix (ECM) remodeling. Despite the fact that gelatinases involve in liver cirrhosis is provided in the literature, their role in the pathogenesis of chronic pancreatitis and non-specific inflammatory bowel diseases is still under investigation. DATA SOURCES: We carried out a PubMed search of Englishlanguage articles relevant to the involvement of gelatinases in the pathogenesis of liver fibrosis, pancreatitis, and non-specific inflammatory bowel diseases. RESULTS: The decreased activity of gelatinases, especially MMP-2, is related to the development of liver fibrosis, probably due to the decrease of capability for ECM remodeling. Similar situation can be found in chronic pancreatitis; however, reports on this matter are rare. The presence of non-specific inflammatory bowel diseases results in MMP-9 activity elevation. CONCLUSION: The fluctuation of gelatinases activity during liver fibrosis, chronic pancreatitis and non-specific inflammatory bowel diseases is observed, but the exact role of these enzymes demands further studies. 展开更多
关键词 matrix metalloproteinase liver fibrosis chronic pancreatitis non-specific inflammatory bowel diseases
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Detection of Prorocentrum donghaiense using sandwich hybridization integrated with nuclease protection assay 被引量:2
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作者 CHEN Jie ZHEN Yu +1 位作者 MI Tiezhu YU Zhigang 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2009年第2期121-126,共6页
Prorocentrum donghaiense is an important harmful algae bloom (HAB) causing creature in China's seas, and the conventional visual detection can not cope with long-term monitoring and highthroughput sampling projects... Prorocentrum donghaiense is an important harmful algae bloom (HAB) causing creature in China's seas, and the conventional visual detection can not cope with long-term monitoring and highthroughput sampling projects. An assay for P. donghaiense with sandwich hybridization integrated with nuclease protection assay (NPA-SH) was established. Tests with mixed samples and spiked field ones confirmed its good specificity and sensitivity. The cell number of P. donghaiense correlated well with the optical density, and the regression equation is y=4× 10^- 6x+ 0.694 9, in which x is the cell number, and y is the optical density, with r2=0.953 5. These results show that the NPA-SH method has good feasibility in the detection of P. donghaiense. Results of NPA-SH and microscopy are excellent for each sample. The NPA-SH method was a simple way in quantitative detection of P. donghaiense, and the whole process could be finished in about six hours, which provided a new approach in high-throughput sampling and long-term monitoring of P. donghaiense. 展开更多
关键词 Prorocentrum donghaiense ribosomal RNA S1 enzyme sandwich hybridization integrated with nuclease protection assay (NPA-SH)
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Influences of immersion bathing in Bacillus velezensis DY-6 on growth performance,non-specific immune enzyme activities and gut microbiota of Apostichopus japonicus 被引量:3
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作者 WANG Jinyan LI Bin +3 位作者 WANG Yingeng LIAO Meijie RONG Xiaojun ZHANG Zheng 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2019年第4期1449-1459,共11页
In this study, the influences of immersion bathing in different concentrations of Bacillus velezensis DY-6 on the body weight gain rate and non-specific immune enzyme activities of the coelom fluid of sea cucumber (Ap... In this study, the influences of immersion bathing in different concentrations of Bacillus velezensis DY-6 on the body weight gain rate and non-specific immune enzyme activities of the coelom fluid of sea cucumber (Apostichopus japonicus) were determined in order to obtain the optimum bacterial concentration. The gut microbiota change in A. japonicus was then analyzed through high-throughput sequencing during the immersion bathing in B. velezensis DY-6 at the optimum concentration for 49 d. The results illustrate that the body weight growth rate of all bathing groups was higher than that of the control. The highest growth rate (25.3%) was achieved when the bacterial concentration was 1×10^3 CFU/mL. The activities of non-specific immune enzymes (ACP, AKP, SOD and LZM) of all bathing groups increased, and the activities of the enzymes of groups bathed with the bacterium at 1×10^3 and 1×10^4 CFU/mL reached the highest on day 21 and day 28. Taking the growth rate and economic cost into consideration, the optimum concentration of B. velezensis DY-6 was 1×10^3 CFU/mL. The influences of immersion bathing in B. velezensis DY-6 at 1×10^3 CFU/mL on the gut microbiota of A. japonicus were then evaluated through 16S rDNA sequencing analysis. Results showed that the gut microbiota changed with the addition of B. velezensis DY-6, and the richness and diversity of the gut microbiota peaked twice on day 14 and day 21, respectively. In association with the non-specific immune enzyme activities and if day 28 was selected as the dividing point, the community structure of the gut microbiota could be obviously divided into two types. The correlation analysis revealed that the non-specific immune enzyme activities were correlated significantly to some gut bacteria (in the phyla Firmicutes, Proteobacteria, and Bacteroidetes) after immersion bathing in B. velezensis DY-6. Our findings will provide the theoretical foundation for probiotic application in sea cucumber farming. 展开更多
关键词 Apostichopus JAPONICUS BACILLUS velezensis non-specific immune enzyme gut microbiota correlation
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Effect of Dietary Alanyl-glutamine Supplementation on Growth Performance, Development of Intestinal Tract, Antioxidant Status and Plasma Non-specific Immunity of Young Mirror Carp(Cyprinus carpio L.) 被引量:3
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作者 Xu Hong Zhu Qing +5 位作者 Wang Chang-an Zhao Zhi-gang Luo Ling Wang Lian-sheng Li Jin-nan Xu Qi-you 《Journal of Northeast Agricultural University(English Edition)》 CAS 2014年第4期37-46,共10页
Exogenous alanyl-glutamine(Aln-Gln) was evaluated for its effects on growth performance, intestinal structure and function, antioxidant status and non-specific immunity of young carp(Cyprinus carpio L.). Six diets... Exogenous alanyl-glutamine(Aln-Gln) was evaluated for its effects on growth performance, intestinal structure and function, antioxidant status and non-specific immunity of young carp(Cyprinus carpio L.). Six diets supplemented with 0, 2.5, 5.0, 7.5, 10.0, or 15.0 g · kg-1 of Aln-Gln were fed to fish for 12 weeks. Supplementation with 7.5, 10.0, or 15.0 g · kg-1 of Aln-Gln significantly increased weight gain rate(WGR), protein efficiency ratio(PER), but feed conservation rate(FCR) and survival were not affected(P〉0.05). The intestinal fold height and number, digestive enzyme, Na+, K+-ATPase activities was found to be significantly high(P〈0.05) with increasing dietary Aln-Gln supplementation up to 7.5 g · kg-1, but there were no significant differences for Aln-Gln supplementation from 7.5 to 15.0 g · kg-1. The glutathione peroxidase(GPX) activity, glutathione(GSH), superoxide dismutase(SOD) activity increased and malondialdehyde(MDA) levels decreased significantly(P〈0.05) in the intestine, hepatopancreas, plasma and muscles. The plasma complement-3(C3) and complement-4(C4) levels were significantly(P〈0.05) improved at 5.0 g · kg-1 level and decreased when over 7.5 g · kg-1. The plasma lysozyme(LSZ) activity increased significantly(P〈0.05) at 7.5, 10.0, or 15.0 g · kg-1 level. In summary, the results showed that Aln-Gln improved growth performance, development and function of the intestine, the activity of the antioxidant defense system and the plasma non-specific immunity of the carps. The optimal Aln-Gln level was 8.24 g · kg-1 diet for WGR based on broken-line regression model analysis. 展开更多
关键词 ALANYL-GLUTAMINE CARP growth INTESTINE antioxidation properties non-specific immunity
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Carbohydrate malabsorption in patients with non-specific abdominal complaints 被引量:2
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作者 Peter Born 《World Journal of Gastroenterology》 SCIE CAS CSCD 2007年第43期5687-5691,共5页
Non-specific abdominal complaints are a considerable problem worldwide. Many patients are affected and many differential diagnoses have to be considered. Among these, carbohydrate malabsorption seems to play an import... Non-specific abdominal complaints are a considerable problem worldwide. Many patients are affected and many differential diagnoses have to be considered. Among these, carbohydrate malabsorption seems to play an important role. However, so far, only incomplete absorption of lactose is broadly accepted, while the malabsorption of fructose and sorbitol is still underestimated, although in many parts of the world it is much more frequent. Despite the success of dietary interventions in many patients, there are still a lot of unanswered questions that make further investigations 展开更多
关键词 non-specific abdominal disorders Carbohydrate malabsorption Fructose Sorbitol Lactose Dietary intervention
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Effects of Size Grading on Growth and Non-Specific Immunity Factors of the Shrimp Litopenaeus vannamei Boone 被引量:2
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作者 LI Yu-quan LI Jian WANG Qing-yin 《Agricultural Sciences in China》 CAS CSCD 2010年第3期416-422,共7页
The study aims to determine the effects of graded farming on growth performance and non-specific immunity factors of shrimp Litopenaeus vannamei Boone. Three size groups of shrimp, i.e., the small size group [Gs, with... The study aims to determine the effects of graded farming on growth performance and non-specific immunity factors of shrimp Litopenaeus vannamei Boone. Three size groups of shrimp, i.e., the small size group [Gs, with an average body length (BL) of (3.04 ± 0.36) cm and body weight (BW) (0.412± 0.35) g], the large group [GL, with a BL of (4.29±0.55) cm and BW of (1.098 ±0.42) g], and the ungraded group [Gm, with a BL of (3.47±0.81) cm and BW of (0.611 ±0.79) g], were reared under the same conditions for 8 wk. Growth performance and non- specific immunity factors were measured. The results showed that BW gain, biomass gain and the specific growth rate of body length (SGRL) were significantly influenced by size grading (one-way ANOVA, P 〈 0.05). The peroxidase (POD) and antibacterial (Ua) activities of GL were lower than those of G. Superoxide dismutase (SOD) and lysozyme (U1) activities of Gm were lower than those of G. No significant difference (P = 0.121 〉 0.05) was found on phenoloxidase (PO) activity among the three size groups. Synthetically, size grading could enhance growth and rearing efficiency, and did not have a significant influence on the immunity of L. vannamei Boone. Therefore, graded fanning in L. vannamei Boone was feasible in the culture practice. 展开更多
关键词 Litopenaeus vannamei Boone graded farming GROWTH non-specific immunity factor
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Preparation of human decellularized peripheral nerve allograft using amphoteric detergent and nuclease 被引量:1
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作者 Joo-Yul Bae Suk Young Park +2 位作者 Young Ho Shin Shin Woo Choi Jae Kwang Kim 《Neural Regeneration Research》 SCIE CAS CSCD 2021年第9期1890-1896,共7页
Animal studies have shown that amphoteric detergent and nuclease(DNase I and ribonuclease A) is the most reliable decellularization method of the peripheral nerve. However, the optimal combination of chemical reagents... Animal studies have shown that amphoteric detergent and nuclease(DNase I and ribonuclease A) is the most reliable decellularization method of the peripheral nerve. However, the optimal combination of chemical reagents for decellularization of human nerve allograft needs further investigation. To find the optimal protocol to remove the immunogenic cellular components of the nerve tissue and preserve the basal lamina and extracellular matrix and whether the optimal protocol can be applied to larger-diameter human peripheral nerves, in this study, we decellularized the median and sural nerves from the cadavers with two different methods: nonionic and anionic detergents(Triton X-100 and sodium deoxycholate) and amphoteric detergent and nuclease(3-[(3-cholamidopropyl)dimethylammonio]-1-propanesulfonate(CHAPS), deoxyribonuclease I, and ribonuclease A). All cellular components were successfully removed from the median and sural nerves by amphoteric detergent and nuclease. Not all cellular components were removed from the median nerve by nonionic and anionic detergent. Both median and sural nerves treated with amphoteric detergent and nuclease maintained a completely intact extracellular matrix. Treatment with nonionic and anionic detergent decreased collagen content in both median and sural nerves, while the amphoteric detergent and nuclease treatment did not reduce collagen content. In addition, a contact cytotoxicity assay revealed that the nerves decellularized by amphoteric detergent and nuclease was biocompatible. Strength failure testing demonstrated that the biomechanical properties of nerves decellularized with amphoteric detergent and nuclease were comparable to those of fresh controls. Decellularization with amphoteric detergent and nuclease better remove cellular components and better preserve extracellular matrix than decellularization with nonionic and anionic detergents, even in large-diameter human peripheral nerves. In Korea, cadaveric studies are not yet legally subject to Institutional Review Board review. 展开更多
关键词 median nerve sural nerve nuclease DETERGENT human decellularized nerve graft
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Effects of the Chinese Medicinal Herb Com plex Additives on Non-specific Immunity of Amursturgeon( Acipenser schrencki Brandt) 被引量:1
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作者 Wang Di Liu Hongbai 《Animal Husbandry and Feed Science》 CAS 2014年第3期123-126,130,共5页
This study was to investigate the effects of aqueous decotion from three Chinese medicinal herb additives ( Cyrtomium fortunei, prescription I and prescription II) on non-specific immunity of 1 + age old Amur sturg... This study was to investigate the effects of aqueous decotion from three Chinese medicinal herb additives ( Cyrtomium fortunei, prescription I and prescription II) on non-specific immunity of 1 + age old Amur sturgeon (Acipenser schrencki Brandt) by oral perfusion. Cyrtomiumfortunei, prescription I and prescription II were orally given to 15 fishes for each experimental group once a day, with the concentration of 9,175 and 36 g/S0 kg body weight, respectively. The administration was lasted for 14 days. Meanwhile, distilled water was orally given as the control. After the experiment, some of the experimental fishes were stimulated with high temperature (30 ℃ ) for two hours. Sampling was performed from fishes treated at 22 ℃ and 30 ℃ for measuring the protein content in the serum, phagocytic activity of leucocytes and the activity of the lysozyme in six tissues. The results indicated that Cyrtomiumfortunei and prescription II could help to enhance the content of various proteins and the phagocytic activity of leucocytes. There was no significant change in the effects between these two additives at either the normal temperature or high temperature. Prescription I did not show an obvious effect on the immunity of fishes at the normal temperature, but it did in promo- ting high-efficiency response and improving immunoregulation of fish shocked by some stimuli. 展开更多
关键词 Chinese medicinal herb Amur sturgeon non-specific immunity Effect
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Comparative pilot study on the effects of pulsating and static cupping on non-specific neck pain and local skin blood perfusion 被引量:2
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作者 Yang Yang Liangxiao Ma +6 位作者 Tingli Niu Junxiang Wang Yue Song Yu Lu Xuezhi Yang Xin Niu Ali Mohammadi 《Journal of Traditional Chinese Medical Sciences》 2018年第4期400-410,共11页
Objective:To compare the effects of pulsating and static cupping on non-specific neck pain and local skin microcirculation blood perfusion,which is a pilot study.Methods:Seventy participants with non-specific neck pai... Objective:To compare the effects of pulsating and static cupping on non-specific neck pain and local skin microcirculation blood perfusion,which is a pilot study.Methods:Seventy participants with non-specific neck pain were randomized to the following groups:low-frequency pulsating cupping(LF,n=20);high-frequency pulsating cupping(HF,n=20);static cupping(SC,n=20),or waiting list(WL,n=10).The LF,HF,and SC received a bilateral 10-minute cupping treatment at Jianzhongshu(SI 15).Outcomes were pain intensity(visual analog scale,VAS),functional status(Neck Disability Index,NDI),and skin blood perfusion at the SI 15,Dazhui(GV 14),and Shenzhu(GV 12)acupoint areas,measured using Laser Speckle Contrast Analysis technology.Results:Both LF and HF groups showed a significant reduction in VAS scores compared with the SC group(9.00,95%Cl 1.05-16.95,P=.027;8.75,95%CI 0.80-16.70,P=.031).There was no significant difference in VAS scores between the LF and HF groups(P>.05)and between NDI scores measured 3 days after intervention among the four groups(P>.05).In the SI 15 area,blood perfusion in the three treatment groups was higher than that in WL group(P<.01),and the perfusion unit(PU)of the HF pulsating group at 5 minutes after intervention was significantly higher compared with the SC group(P<.05).In the GV 14 area,blood perfusion in the two pulsating cupping groups was higher compared with the WL and SC groups after cupping(P<.05).In the GV 12 area,the PU of the LF group was higher compared with the other three groups only at the time of cup removal(P<.05).Conclusion:This study showed that pulsating cupping may have more favorable analgesic effects on non-specific neck pain compared with static cupping,which may be related to its better effect on improving the local skin blood perfusion. 展开更多
关键词 Pulsating CUPPING STATIC CUPPING non-specific neck pain VAS Blood perfusion
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Effect of Ammonia-Nitrogen Stress on Non-specific Immunity of Hybrid Tilapia(Oreochromis niloticus× Oreochromis areus) 被引量:1
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作者 Han Chunyan Zheng Qingmei +1 位作者 Chen Guidan Liu Lixia 《Animal Husbandry and Feed Science》 CAS 2015年第4期226-229,248,共5页
The juveniles of hybrid tilapia ( Oreochromis niloticus x Oreochromis areus) were exposed to ananonia-nitrogen (N) (0, 2.5, 5, 10 and 20 mg/L) for 0, 12, 24, 48 and 72 h to evaluate the effect of ammonia-N stres... The juveniles of hybrid tilapia ( Oreochromis niloticus x Oreochromis areus) were exposed to ananonia-nitrogen (N) (0, 2.5, 5, 10 and 20 mg/L) for 0, 12, 24, 48 and 72 h to evaluate the effect of ammonia-N stress on their non-specific immunity. Results show that the activity of serum lysozyme decreased signifi- candy with extension of stress time (P 〈 0.05). The total antioxidant capacity (T-AOC) and activity of antioxidase in liver were significantly affected. The activi- ty of T-AOC and total superoxide dismutase (T-SOD) of fish exposed to ammonia-N were initially decreasing then increasing ( P 〈 0.05 ). Activities of catalase (CAT) and glutathione peroxidase (GSH-Px) were correlated with concentrations of ammonia-N. Fish exposed to lower concentrations (2.5 mg/L or 5 mg/L) showed decreased CAT activity within 24 h (P 〈 0.05 ), while those exposed to higher concentrations (10 mg/L or 20 mg/L) initially showed increased then decreased activity of CAT. Except for the highest concentration groups, fish exposed to ammonia-N showed inductive activity of GSH-Px ( P 〈 0.05 ). Under the ex- perimental conditions, non-specific immunity of tilapia was affected by ammonia-N stress, and the impact was increased with increased concentration and extension of time. 展开更多
关键词 Oreochromis niloticus x Oreochromis areus Ammonia-N stress non-specific immunity
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Genome engineering and disease modeling via programmable nucleases for insulin gene therapy;promises of CRISPR/Cas9 technology 被引量:1
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作者 Yunus E Eksi Ahter D Sanlioglu +2 位作者 Bahar Akkaya Bilge Esin Ozturk Salih Sanlioglu 《World Journal of Stem Cells》 SCIE 2021年第6期485-502,共18页
Targeted genome editing is a continually evolving technology employing programmable nucleases to specifically change,insert,or remove a genomic sequence of interest.These advanced molecular tools include meganucleases... Targeted genome editing is a continually evolving technology employing programmable nucleases to specifically change,insert,or remove a genomic sequence of interest.These advanced molecular tools include meganucleases,zinc finger nucleases,transcription activator-like effector nucleases and RNA-guided engineered nucleases(RGENs),which create double-strand breaks at specific target sites in the genome,and repair DNA either by homologous recombination in the presence of donor DNA or via the error-prone non-homologous end-joining mechanism.A recently discovered group of RGENs known as CRISPR/Cas9 gene-editing systems allowed precise genome manipulation revealing a causal association between disease genotype and phenotype,without the need for the reengineering of the specific enzyme when targeting different sequences.CRISPR/Cas9 has been successfully employed as an ex vivo gene-editing tool in embryonic stem cells and patient-derived stem cells to understand pancreatic beta-cell development and function.RNA-guided nucleases also open the way for the generation of novel animal models for diabetes and allow testing the efficiency of various therapeutic approaches in diabetes,as summarized and exemplified in this manuscript. 展开更多
关键词 Programmable nucleases CRISPR/Cas9 Stem cells Disease modeling DIABETES Insulin gene therapy
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Ultrafast solvation dynamics at internal sites of staphylococcal nuclease investigated by site-directed mutagenesis
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作者 高光宇 李渝 +3 位作者 王伟 王树峰 Dongping Zhong 龚旗煌 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第1期81-88,共8页
Internal solvation of protein was studied by site-directed mutagenesis, with which an intrinsically fluorescent probe,tryptophan, is inserted into the desired position inside a protein molecule for ultrafast spectrosc... Internal solvation of protein was studied by site-directed mutagenesis, with which an intrinsically fluorescent probe,tryptophan, is inserted into the desired position inside a protein molecule for ultrafast spectroscopic study. Here we review this unique method for protein dynamics research. We first introduce the frontiers of protein solvation, site-directed mutagenesis, protein stability and characteristics, and the spectroscopic methods. Then we present time-resolved spectroscopic dynamics of solvation dynamics inside cavities of active sites. The studies are carried out on a globular protein, staphylococcal nuclease. The solvation at sites inside the protein molecule's cavities clearly reveals characteristics of the local environment. These solvation behaviors are directly correlated to enzyme activity. 展开更多
关键词 ultrafast spectroscopy protein dynamics staphylococcal nuclease(SNase) site-directed mutagenesis
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The Distribution and Substrate Specificity of Extracellular Nuclease Activity in Marine Fungi
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作者 Larissa A. Balabanova Michael V. Pivkin Valery A. Rasskazov 《Open Journal of Marine Science》 2012年第4期188-195,共8页
The distribution and specificity of extracellular nucleases produced by marine fungi belonging to eleven genera, namely: Alternaria, Aspergillus, Aureobasidium, Chaetomium, Fusarium, Gliomastix, Humicola, Penicillium,... The distribution and specificity of extracellular nucleases produced by marine fungi belonging to eleven genera, namely: Alternaria, Aspergillus, Aureobasidium, Chaetomium, Fusarium, Gliomastix, Humicola, Penicillium, Scopulariopsis, Wardomyces, Periconia, have implied its important function in the organic phosphorus and nitrogen circle in the Ocean. The fungal nucleases of 64 isolates tested were more or less specific for single-stranded DNA with a high preferential specificity towards poly-U substrate with forming of 5’-phosphate mononucleotides. A couple of the nucleases were capable of RNA digesting. The highest level of extracellular nucleolytic ability was observed in Penicillium spp. isolates. The tight correlation found between extracellular nuclease activity and the rate of thymidine uptake by actively growing and sporulating marine fungus Penicillium melinii suggests that this nuclease is required for fulfilling the nucleotide pool of precursors of DNA biosynthesis during transformation of hyphae into the aerial mycelium and conidia in stressful environmental conditions. 展开更多
关键词 MARINE Fungi MARINE Environment Single-Strand-Specific nuclease DNASE RNAse SSDNA THYMIDINE Uptake
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Ultrastructural changes in non-specific duodenitis
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作者 Cheng-XinWang Li-JiangLiu JingGuan Xiao-LingZhao 《World Journal of Gastroenterology》 SCIE CAS CSCD 2005年第5期686-689,共4页
AIM: To investigate the ultrastructural and morphological changes of non-specific duodenitis (NSD) in an attempt to grade them according to the extent of the lesions. METHODS: Biopsies were taken from the mucosa of du... AIM: To investigate the ultrastructural and morphological changes of non-specific duodenitis (NSD) in an attempt to grade them according to the extent of the lesions. METHODS: Biopsies were taken from the mucosa of duodenal bulb of 44 patients selected from the patients undergoing upper gastrointestinal endoscopy for epigastric discomforts. From each patient, two pinch biopsies on the same area were obtained from duodenal bulb. One was for scanning electron microscopy and the other was stained with hematoxylin-eosin, Warthin-Starry silver and both were then examined under light microscope. A total of 12 specimens (three from each degree of the normal and I-III of NSD diagnosed and graded by histology) selected from the 44 patients were dehydrated, critical point dried, coated with gold palladium and examined under a JEOL JSM-30 scanning electron microscope (SEM) at 20 kV. RESULTS: According to the ultrastructural morphologic changes, non-specific duodenitis was divided into normal (as control group), mild, moderate and severe degrees according to results of SEM. The normal villi of duodenal bulb were less than 0.2 mm. There were inflammation cells, occasionally red blood cells and macrophages on the mucosal epithelial surface. Erosion and desquamation of epithelium could be seen. Three cases (25%, 3/12) had gastric metaplasia and Helicobacter pylori(H pylori) infection could be found in 5 cases (41.67%, 5/12) in duodenal bulb mucosa. The most distinctive feature was the ulcer-like defect on the surface of epithelial cells. CONCLUSION: Non-specific duodenitis is a separate entity disease caused by different factors. SEM is of value as an aid in the diagnosis of mucosal diseases of duodenum. 展开更多
关键词 non-specific duodenitis Intestinal Mucosa Ultrastructural organization
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Non-specific immune response of bullfrog Rana catesbeiana to intraperitoneal injection of bacterium Aeromonas hydrophila
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作者 张俊杰 邹文政 鄢庆枇 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2008年第3期248-255,共8页
Non-specific immune response of bullfrog Rana catesbeiana to pathogenic Aeromonas hydrophila was studied to 60 individuals in two groups.Each bullfrog in bacterium-injected group was injected intraperitoneally(i.p.) w... Non-specific immune response of bullfrog Rana catesbeiana to pathogenic Aeromonas hydrophila was studied to 60 individuals in two groups.Each bullfrog in bacterium-injected group was injected intraperitoneally(i.p.) with 0.2 ml bacterial suspension at a density of 5.2 × 106 CFU/ml,while each one in control group injected i.p.with 0.2 ml sterile saline solution(0.85%,w/v).Three bullfrogs in both groups were sampled at 0,1,3,7,11,15 and 20 days post-injection(dpi) for the evaluation of non-specific immune parameters.It was observed that intraperitoneal injection of A.hydrophila significantly increased the number of leucocytes and that of NBT-positive cells in peripheral blood.Significant increases in serum bactericidal activity and serum acid phosphatase activity were also observed in the bacterium-injected frogs when compared with those in the control group.However,a significant reduction was detected in vitro in phagocytosis activity of peripheral blood phagocytes.No significant difference in changes in the number of peripheral erythrocytes,serum superoxide dismutase(SOD) activity,and lysozyme activity was detected between the two groups.It is suggested that bullfrogs may produce a series of non-specific immune reactions in response to the A.hydrophila infection. 展开更多
关键词 Rana catesbeiana Aeromonas hydrophila intraperitoneal injection non-specific immune response
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Quantitation of DNA by nuclease P1 digestion and UPLC-MS/MS to assess binding efficiency of pyrrolobenzodiazepine
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作者 Yong Ma Buyun Chen Donglu Zhang 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2020年第3期247-252,共6页
Accurate DNA quantitation is a prerequisite in many biomedical and pharmaceutical studies.Here we established a new DNA quantitation method by nuclease P1 digestion and UPLC-MS/MS analysis.DNA fragments can be efficie... Accurate DNA quantitation is a prerequisite in many biomedical and pharmaceutical studies.Here we established a new DNA quantitation method by nuclease P1 digestion and UPLC-MS/MS analysis.DNA fragments can be efficiently hydrolyzed to single deoxyribonucleotides by nuclease P1 in a short time.The decent stabilities of all the four deoxyribonucleotides were confirmed under different conditions.Deoxyadenosine monophosphate(dAMP)was selected as the surrogate for DNA quantitation because dAMP showed the highest sensitivity among the four deoxyribonucleotides in the UPLC-MS/MS analysis.The linear range in DNA quantitation by this method is 1.2-5000 ng/mL.In the validation,the inter-day and intra-day accuracies were within 90%-110%,and the inter-day and intra-day precision were acceptable(RSD<10%).The validated method was successfully applied to quantitate DNA isolated from tumors and organs of a mouse xenograft model.Compared to the quantitation methods using UV absorbance,the reported method provides an enhanced sensitivity,and it allows for the accurate quantitation of isolated DNA with contamination of RNA and ribonucleotide. 展开更多
关键词 nuclease P1 UPLC-MS/MS DNA quantitation DNA alkylation Pyrrolobenzodiazepine(PBD-Dimer)
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Integration of the nuclease protection assay with sandwich hybridization (NPA-SH) for sensitive detection of Heterocapsa triquetra
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作者 PARK Mirye PARK So Yun +4 位作者 HWANG Jinik JUNG Seung Won 3LEE Juyun CHANG Man LEE Taek-Kyun 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2018年第5期107-112,共6页
Microalgae are photosynthetic microorganisms that function as primary producers in aquatic ecosystems. Some species of microalgae undergo rapid growth and cause harmful blooms in marine ecosystems. Heterocapsa triquet... Microalgae are photosynthetic microorganisms that function as primary producers in aquatic ecosystems. Some species of microalgae undergo rapid growth and cause harmful blooms in marine ecosystems. Heterocapsa triquetra is one of the most common bloom-forming species in estuarine and coastal waters worldwide. Although this species does not produce toxins, unlike some other Heterocapsa species, the high density of its blooms can cause significant ecological damage. We developed a H. triquetra species-specific nuclease protection assay sandwich hybridization(NPA-SH) probe that targets the large subunit of ribosomal RNA(LSU r RNA). We tested probe specificity and sensitivity with five other dinoflagellates that also cause red tides. Our assay detected H.triquetra at a concentration of 1.5×10^4 cells/m L, more sensitive than required for a red-tide guidance warning by the Korea Ministry of Oceans and Fisheries in 2015(3.0×10^4 cells/m L). We also used the NPA-SH assay to monitor H. triquetra in the Tongyeong region of the southern sea area of Korea during 2014. This method could detect H.triquetra cells within 3 h. Our assay is useful for monitoring H. triquetra under field conditions. 展开更多
关键词 nuclease protection assay sandwich hybridization Heterocapsa triquetra red tide monitoring
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Transcribed single nucleotide polymorphism: Ideal markers for detecting gene imprinting by 5' nuclease assay
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作者 朱冠山 万谟彬 +1 位作者 朱忠政 郑瑞英 《Journal of Medical Colleges of PLA(China)》 CAS 2002年第4期242-246,共5页
Objective: To establish a novel approach for quick and highly efficient verification of human gene imprinting. Methods: A pair of dye-labelled probes, 5' nuclease assay was combined with RT-PCR to determine the ge... Objective: To establish a novel approach for quick and highly efficient verification of human gene imprinting. Methods: A pair of dye-labelled probes, 5' nuclease assay was combined with RT-PCR to determine the genotype of a transcribed single nucleotide polymorphism (SNP) rs705(C>T) of a known imprinted gene, small nuclear ribonucleotide protein N (SNRPN), on both genomic DNA and cDNA of human lym-phoblast cell lines. Results: Allele discrimination showed a clear monoallelic expression pattern of SNRPN, which was confirmed by RT-PCR based restriction fragment length polymorphism (RFLPs). Pedigree analysis verified the paternal origin of expressed allele, which was in consistency with previous report. Conclusion: Transcribed SNP is an ideal marker for detecting gene imprinting by 5' nuclease assay. This approach also may be used to discover differential allele expression of non-imprinted genes, finding out gene cis-acting functional polymorphism. 展开更多
关键词 single nucleotide polymorphism genomic imprinting 5' nuclease assay
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