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Alveolar echinococcosis-spreading disease challenging clinicians: A case report and literature review 被引量:14
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作者 Georgi Atanasov Christoph Benckert +7 位作者 Armin Thelen Dennis Tappe Matthias Frosch Dieter Teichmann Thomas FE Barth Christian Wittekind Stefan Schubert Sven Jonas 《World Journal of Gastroenterology》 SCIE CAS 2013年第26期4257-4261,共5页
Human alveolar echinococcosis (AE) is a potentially deadly disease; recent studies have shown that the endemic area of Echinococcus multilocularis , its causative agent, is larger than previously known. This disease h... Human alveolar echinococcosis (AE) is a potentially deadly disease; recent studies have shown that the endemic area of Echinococcus multilocularis , its causative agent, is larger than previously known. This disease has low prevalence and remains underreported in Europe. Emerging clinical data show that diagnostic difficulties are still common. We report on a 76-year old patient suffering from AE lesions restricted to the left lobe of the liver who underwent a curative extended left hemihepatectomy. Prior to the resection a liver biopsy under the suspicion of an atypical malignancy was performed. After the intervention he developed a pseudoaneurysm of the hepatic artery that was successfully coiled. Surprisingly, during surgery, the macroscopic appearance of the tumour revealed a growth pattern that was rather typical for cystic echinococcosis (CE), i.e. , a gross tumour composed of multiple large vesicles with several centimeters in diameter. In addition, there were neither extensive adhesions nor infiltrations of the neighboring pancreas and diaphragm as was expected from previous imaging results. The unexpected diagnosis of AE was confirmed by definite histopathology, specific polymerase chain reaction and serology results. This is a rare case of unusual macroscopic presentation of AE that posed immense diagnostic challenges and had an eventful course. To our knowledge this is the first case of an autochthonous infection in this particular geographic area of Germany, the federal state of Saxony. This report may provide new hints for an expanding area of risk for AE and emphasizes the risk of complications in the scope of diagnostic procedures and the limitations of modern radiological imaging. 展开更多
关键词 ALVEOLAR ECHINOCOCCOSIS ECHINOCOCCUS multilocularis autochthonous infection Liver resection HEMIHEPATECTOMY
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广西两种三水铝石铝土矿成矿的差异性 被引量:13
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作者 谌建国 刘云华 许俊文 《地学前缘》 EI CAS CSCD 1999年第B05期251-256,共6页
广西2种岩溶型三水铝石铝土矿都是含三水锅石和针铁矿的大型矿床,但二者成矿过程通异。平果式铝土矿是在晚白垩世至老第三纪湿热海洋性气候下,硬水锅石被泥石流搬运至异地,经受了年积温104℃,降水量近2.0m/a的强烈大气降水淋滤。... 广西2种岩溶型三水铝石铝土矿都是含三水锅石和针铁矿的大型矿床,但二者成矿过程通异。平果式铝土矿是在晚白垩世至老第三纪湿热海洋性气候下,硬水锅石被泥石流搬运至异地,经受了年积温104℃,降水量近2.0m/a的强烈大气降水淋滤。生成三水锅石贵港式原地残积矿床的更新世成矿期气温和降水量均低于前者,低水活度导致铁矿物中的赤铁矿的高含量。热力学稳定性图解显示:平果式三水铝石-针铁矿组合稳定在t=27℃,a(H2O)≥0.88的高铝体系中;贵港式针铁矿-赤铁矿组合稳定在t=22℃,a(H2O)=0.724的低铝体系中。均不含软水铝石。 展开更多
关键词 岩溶型 三水铝石铝土矿 原地生成 广西 铝矿床
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光老化聚苯乙烯对河口内源溶解性有机质生成和转化的影响
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作者 闫文罡 杨健 +5 位作者 王前进 赵好轩 王乾 杨传玺 高雅 肖宜华 《环境科学学报》 CAS CSCD 北大核心 2024年第5期207-217,共11页
微塑料(MPs)向水体环境释放有机质影响有机碳库引起了广泛关注,但MPs如何影响水体内源溶解性有机质(DOM)的生成和转化仍不清晰.本研究通过聚苯乙烯微塑料(PS-MPs)与河口原水样的共培养实验研究了MPs对浮游藻类生产和微生物转化DOM的影响... 微塑料(MPs)向水体环境释放有机质影响有机碳库引起了广泛关注,但MPs如何影响水体内源溶解性有机质(DOM)的生成和转化仍不清晰.本研究通过聚苯乙烯微塑料(PS-MPs)与河口原水样的共培养实验研究了MPs对浮游藻类生产和微生物转化DOM的影响.结果表明,PS-MPs能够抑制浮游藻类的生长,培养42 d时PS-MPs对叶绿素a的抑制率达到了67.3%,光老化过程能够增强PS-MPs对叶绿素a的抑制作用.PS-MPs可以通过释放有机质使水中溶解性有机碳(DOC)浓度升高,42d时光照PS-MPs处理组DOC浓度为48.2 mg·L^(-1),显著高于空白光照对照组(16.4 mg·L^(-1)).紫外-可见吸收光谱结果表明,与对照组相比,PS-MPs处理组DOM吸收系数显著增加,分子芳香性降低.三维荧光光谱耦合平行因子分析(EEM-PARAFAC)解析出3类DOM荧光组分:陆源类腐殖质C1组分(λ_(Ex)/λ_(Em)=255(310)nm/444 nm)、微生物源类腐殖质C2组分(λ_(Ex)/λ_(Em)=240(290)nm/354 nm)和自生源类蛋白C3组分(λ_(Ex)/λ_(Em)=265 nm/334 nm).在光照培养42 d时,PS-MPs处理组DOM总荧光强度(1.36R.U.)显著高于空白对照组(0.725 R.U.),荧光强度的增加主要来源于类腐殖质C1组分荧光强度的增加,但光老化PS-MPs处理组DOM荧光强度与对照组相比无显著变化.水体微生物16S rRNA高通量测序结果表明,PS-MPs存在时水体变形菌属等专性厌氧异养微生物丰度增加,蓝细菌等产氧性原核微生物丰度下降.本研究结果对于准确评估MPs污染对水体有机碳库的影响有一定的指示意义. 展开更多
关键词 微塑料(MPs) 溶解性有机质(DOM) 光老化 内源 三维荧光光谱 微生物
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Selection of Lactic Acid Bacteria Isolated from San Simón da Costa Cheese (PDO) in Order to Develop an Autochthonous Starter Culture 被引量:3
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作者 Leticia González Araceli Fernández Cuadrillero +2 位作者 José María Castro Ana Bernardo María Eugenia Tornadijo 《Advances in Microbiology》 2015年第11期748-759,共12页
Traditional cheeses are an important reservoir of microbial diversity that can have important biotechnological applications, especially with a view to improving the characteristics unique to each type of cheese, and i... Traditional cheeses are an important reservoir of microbial diversity that can have important biotechnological applications, especially with a view to improving the characteristics unique to each type of cheese, and in this respect, starter cultures consisting of autochthonous lactic acid bacteria strains are of particular interest. In the present study, we investigated lactic acid bacteria population diversity in San Simón da Costa cheese (PDO, Galicia, Spain) and found a predominance of the genus Lactobacillus, which by the end of ripening accounted for 78% of the strains isolated in Rogosa agar, around 40% of those in M17 agar and about 10% of those in MSE agar. The main species of lactic acid bacteria identified were Lactococcus lactis subsp. lactis, Lactobacillus casei subsp. casei, Lb. paracasei subsp. paracasei, Leuconostoc mesenteroides and Enterococcus faecalis. Virtually all the strains studied from a technological point of view yielded more than or equal to 0.24 g 100 mL-1 lactic acid. Lactococcus lactis subsp. lactis (SS 194), Lactobacillus paracasei (SS 1695 and SS 1689) and Enterococcus faecalis (SS 1378 and SS 1449) strains exhibited the greatest proteolytic capacity. Based on the overall technological aptitude of the tested strains, we can propose starter cultures and co-cultures that include different combinations of previous strains with a view to manufacturing San Simón da Costa cheese from pasteurised milk. 展开更多
关键词 COW Milk CHEESE LACTIC Acid Bacteria Enzymatic Activities autochthonous STARTER
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Influence of the biological carbon pump effect on the sources and deposition of organic matter in Fuxian Lake, a deep oligotrophic lake in southwest China 被引量:2
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作者 Haibo He Zaihua Liu +5 位作者 Chongying Chen Yu Wei Qian Bao Hailong Sun Yundi Hu Hao Yan 《Acta Geochimica》 EI CAS CSCD 2019年第5期613-626,共14页
Biological carbon pumping(BCP)is a key process in which dissolved inorganic carbon in terrestrial aquatic ecosystems is utilized by aquatic autotrophs for photosynthesis and transformed into autochthonous organic matt... Biological carbon pumping(BCP)is a key process in which dissolved inorganic carbon in terrestrial aquatic ecosystems is utilized by aquatic autotrophs for photosynthesis and transformed into autochthonous organic matter(AOC).However,the mechanisms underlying BCP and the amount of generated AOC deposited effectively,are still poorly understood.Therefore,we conducted a systematic study combining modern hydrochemical monitoring and a sediment trap experiment in Fuxian Lake(Yunnan,SW China),the second-deepest plateau,oligotrophic freshwater lake in China.Temperature,pH,EC(electrical conductivity),DO(dissolved O2),[HCO3^-],[Ca^2+],SIc,partial CO2(pCO2)pressure,and carbon isotopic compositions of HCO3^-(δ^13CDIc)in water from Fuxian Lake all displayed distinct seasonal and vertical variations.This was especially apparent in an inverse correlation between pCO2 and DO,indicating that variations of hydrochemistry in the lake water were mainly controlled by the metabolism of the aquatic phototrophs.Furthermore,the lowest C/N ratios and highestδ^13Corg were recorded in the trap sediments.Analyses of the C/N ratio demonstrated that the proportions of AOC ranged from 30%to 100%of all OC,indicating that AOC was an important contributor to sedimentary organic matter(OC).It was calculated that the AOC flux in Fuxian Lake was 20.43 t C km^-2 in 2017.Therefore,AOC produced by carbonate weathering and aquatic photosynthesis could potentially be a significant carbon sink and may have an important contribution to solving the lack of carbon sinks in the global carbon cycle. 展开更多
关键词 Carbonate weathering Hydrochemical variation BIOLOGICAL CARBON PUMP EFFECT Sediment trap autochthonous organic CARBON CARBON sink
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Tectonic implication of stockwork microbreccias 被引量:4
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作者 ZHANGJiasheng HUANGXiongnan LIUJianmin 《Chinese Science Bulletin》 SCIE EI CAS 2005年第1期67-74,共8页
The stockwork microbreccia found in the Dabie and Helan Mountains bears no relation to either meteorite impact and cryptoexplosion, or fault displacement. It is con- trolled by tensional or transtensional fracture net... The stockwork microbreccia found in the Dabie and Helan Mountains bears no relation to either meteorite impact and cryptoexplosion, or fault displacement. It is con- trolled by tensional or transtensional fracture network in relatively hard felsic crystalline rocks, appearing as breccia with dark cryptocrystalline matrix. The kilometer-scale dis- tribution and complicated relation to fracture system of the stockwork microbreccias, randomly distributed autochtho- nous fragments of host rock, ultracataclasis without notable displacement in the cryptocrystalline matrix, and a probable solid-state amorphization deformation mechanism all suggest that large-scale, high-energy and rapid brittle fracturing event might have occurred in the rocks at relatively deep crustal level in the areas. 展开更多
关键词 网状脉细角砾岩 大别山脉 隐晶质矩阵 固态非晶化 地壳运动
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Gravity and Aeromagnetic Studies of the Filabusi Greenstone Belt, Zimbabwe Craton: Regional and Geotectonic Implications
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作者 Rubeni T. Ranganai 《International Journal of Geosciences》 2012年第5期1048-1064,共17页
The Filabusi greenstone belt (FGB), Zimbabwe craton, has been geologically remapped relatively recently but its regional tectonic setting and subsurface structure have, until now, remained unresolved. This paper prese... The Filabusi greenstone belt (FGB), Zimbabwe craton, has been geologically remapped relatively recently but its regional tectonic setting and subsurface structure have, until now, remained unresolved. This paper presents gravity and aeromagnetic studies that have been undertaken to provide this important information, and also extend mapping to areas of poor exposure. Several new NNW-trending dykes and structures cutting across the greenstone belt have been revealed, as well as a major extension of one of the metakomatiitic-BIF units, the Shamba Range. ESE-trending dykes identified in the southeast appear on a regional scale to be part of the giant Okavango dyke swarm in northern Botswana. An ~3 km wide NNE-striking magnetic low occurs over the Irisvale-Lancaster shear zone (ILSZ) on the extreme west of the FGB where it roughly marks the boundary with the Bulawayo greenstone belt. Magnetic anomaly trends over ultramafic schists are consistent with strike-slip movement along the ILSZ, and together with the gravity anomalies, support northeasterly directed detachment of the adjacent Fort Rixon belt from the Bulawayo-Filabusi belt. The Bouguer gravity anomaly map shows that the FGB is characterised by a well defined positive anomaly up to 37 mGal, whose symmetry and extent confirm the postulated synclinal structure of the belt. Isolated oval shaped small gravity lows generally correlate with sub-/out-cropping K-rich post-volcanic granite plutons. 2.5D gravity models along three profiles across the greenstone belt show a simple “basin shape” with a possible maximum depth extent of only 4.5 km, compared to an estimated stratigraphic thickness of about 9.0 km. This suggests a truncation at shallow depth of the structurally repeated lithologies. Gravity data and models support the proposed FGB model;deposition of volcanics in an extensional, structurally determined, evolving basin. This autochthonous setting is consistent with other greenstone belts in the Zimbabwe craton and other parts of the world. 展开更多
关键词 Granite-Greenstone Terrain GRAVITY ANOMALIES Depth Extent Magnetic Structural Interpretation GREENSTONE Belt Evolution autochthonous Origin
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Hepatitis E: An Underdiagnosed, Emerging Infection in Nonendemic Regions
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作者 Steven De Keukeleire Marijke Reynders 《Journal of Clinical and Translational Hepatology》 SCIE 2015年第4期288-291,共4页
Although hepatitis E virus(HEV)is the primary cause of enterically transmitted acute hepatitis and jaundice in developing countries,locally acquired HEV infections are increasing in nonendemic countries.As such,HEV is... Although hepatitis E virus(HEV)is the primary cause of enterically transmitted acute hepatitis and jaundice in developing countries,locally acquired HEV infections are increasing in nonendemic countries.As such,HEV is emerging as an underdiagnosed cause of infection.This report describes three clinically variable cases of HEV infection with unusual clinical presentations.These cases highlight the fact that HEV should be considered in the differential diagnosis of patients with unexplained hepatitis(acute or chronic)with or without extrahepatic manifestations.HEV should also be considered in patients with persistently elevated liver enzymes who have not travelled to known HEV-endemic regions.Lack of knowledge among physicians and an absence of standardized diagnostic tests may result in increased morbidity and mortality from HEV infection. 展开更多
关键词 autochthonous hepatitis E Hepatitis E HEV RNA Polymerase chain reaction SEROPREVALENCE
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Hepatitis E in Israel: A nation-wide retrospective study
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作者 Ortal Erez-Granat Tamar Lachish +2 位作者 Nili Daudi Daniel Shouval Eli Schwartz 《World Journal of Gastroenterology》 SCIE CAS 2016年第24期5568-5577,共10页
AIM: To investigate the epidemiology, risk factors and clinical course of acute hepatitis E virus (HEV) infection in Israel, an industrialized country.METHODS: A retrospective analysis of acute HEV cases diagnosed in ... AIM: To investigate the epidemiology, risk factors and clinical course of acute hepatitis E virus (HEV) infection in Israel, an industrialized country.METHODS: A retrospective analysis of acute HEV cases diagnosed in Israel from 1993 to 2013. Acute HEV was defined by ALT/AST elevation and a positive HEV PCR test or positive anti-HEV-IgM serology. HEV RNA was tested by quantitative reverse transcription PCR. Antibodies to HEV were tested retrospectively using an ELISA assay. HEV-RNA was sequenced using RT-PCR of ORF1 and ORF2 regions to diagnose genotype of the virus. Epidemiologic and clinical data were collected by reviewing the clinical files and through a telephone interview according to a structured questionnaire.RESULTS: Acute HEV was diagnosed in 68 patients. Among the 59 patients who gave an informed consent and were interviewed, 41% of infections were autochthonous (acquired in Israel), 44% travel-related and 15% imported by foreign workers. Autochthonous patients were mainly females (62.5%), more than half of them pregnant, 26% recalled consuming food or water in areas with poor sanitation, 44% ate non-kosher meat. Fulminant hepatitis developed in 3 patients (5%), all of them were females, two of them with post-partum infection, all acquired the disease in Israel (autochthonous). Israeli travelers with imported infection were predominantly males (73%), acquired the disease in the Indian subcontinent (81%), with 100% reporting having consumed fresh vegetables and drinks with ice cubes abroad. Six patients&#x02019; sera were tested for genotype and revealed HEV genotype 1 (all cases acquired in the Indian subcontinent).CONCLUSION: This is the first report which highlights the existence of hepatitis E as an autochthonous infection in Israel. Imported HEV originates mostly from the Indian subcontinent. 展开更多
关键词 Hepatitis E autochthonous TRAVEL Foreign workers PREGNANCY POST-PARTUM INDIA Nepal Indian subcontinent Israel
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杏鲍菇中土著益生菌的筛选与鉴定 被引量:2
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作者 熊荣园 林俊芳 +2 位作者 叶志伟 刘英丽 郭丽琼 《中国食品学报》 EI CAS CSCD 北大核心 2016年第5期217-223,共7页
以杏鲍菇的表皮为材料,通过添加溴甲酚紫的MRS培养基分离得到56株土著菌。以降解亚硝酸盐和降胆固醇的综合能力为指标进行复筛,得到4株土著益生菌。对这4株菌进行耐酸和耐胆盐的模拟试验,得到1株降亚硝酸盐和胆固醇综合能力较强以及耐... 以杏鲍菇的表皮为材料,通过添加溴甲酚紫的MRS培养基分离得到56株土著菌。以降解亚硝酸盐和降胆固醇的综合能力为指标进行复筛,得到4株土著益生菌。对这4株菌进行耐酸和耐胆盐的模拟试验,得到1株降亚硝酸盐和胆固醇综合能力较强以及耐胆盐能力较强的菌株C3。通过生理生化试验和16Sr DNA鉴定,确定其为乳酸乳球菌。 展开更多
关键词 杏鲍菇 土著益生菌 亚硝酸盐 胆固醇
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Gluten-free flour fermented with autochthonous starters for sourdough production:Effect of the fermentation process
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作者 R.Lancetti E.Salvucci +2 位作者 M.Moiraghi G.T.Pérez L.S.Sciarini 《Food Bioscience》 SCIE 2022年第3期176-183,共8页
Refined rice flour and wholegrain quinoa and buckwheat flours were used to prepare gluten-free sourdoughs.Two autochthonous LAB strains were isolated,one from quinoa (Limosilactobacillus fermentum Q3) and the other fr... Refined rice flour and wholegrain quinoa and buckwheat flours were used to prepare gluten-free sourdoughs.Two autochthonous LAB strains were isolated,one from quinoa (Limosilactobacillus fermentum Q3) and the other from buckwheat (Lim.fermentum T5).Lactiplantibacillus plantarum ATCC8014 was used as a reference starter.Two fermentation processes were evaluated,a single-step process (30℃,24 h) named SD1,and a daily refreshment process (backslopping for 10 days) named SD2.Sourdoughs were freeze-dried prior to analyses.Pasting properties,pentosan and polyphenol contents,and antioxidant activity were analysed.Flour properties were significantly modified by fermentation.Polyphenol extractability increased during fermentation,which resulted in a higher antioxidant capacity,mainly through a reducing mechanism.Q3 and T5 strains produced the most remarkable modifications of flour properties.Differences were found between both fermentation processes,mainly as a result of the development of different microbiota.The single-step fermentation (SD1) showed to be a simple and appropriate method for improving flour properties. 展开更多
关键词 Rice QUINOA Buckwheat Wholegrain flours Spontaneous sourdough autochthonous starter Antioxidant capacity Flour modification
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Autochthonous Dolomitization and Dissolution in the Microbial Carbonate Rocks of the Fengjiawan Formation in the Ordos Basin
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作者 ZHANG Jing ZHANG Baomin +1 位作者 ZHANG Shuichang WANG Huajian 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2022年第4期1376-1387,共12页
Many euhedral dolomite crystals and related pores are found in the microbial siliceous stromatolite dolomite and siliceous oolitic dolomite in the Fengjiawan Formation of the Mesoproterozoic Jixian System in the south... Many euhedral dolomite crystals and related pores are found in the microbial siliceous stromatolite dolomite and siliceous oolitic dolomite in the Fengjiawan Formation of the Mesoproterozoic Jixian System in the southern Ordos Basin.With the application of the microscope,scanning electron microscope,cathodoluminescence and in-situ trace element imaging,it can be seen that different from the phase I dolomite that was damaged by silicification,the intact euhedral phase II dolomite occurred through dolomitization after silicification,concentrated mainly in the organic-rich dark laminae of the stromatolite and the dark spheres and cores of the ooids.A considerable number of phase II dolomite crystals were dissolved,giving rise to mold pores and vugs which constituted the matrix pores and also the major pore space of the Fengjiawan Formation.The formation and dissolution of the dolomite were controlled by the microenvironment favorable,respectively,for carbonate precipitation and dissolution under the influence of microbial biological activities and related biochemical reactions.The driving force and material supply of dolomitization and dissolution were confined to the fabrics enriched with microorganisms,which are highly autochthonous.This mechanism may be a key factor for the development of Precambrian dolomite and related reservoirs,in the context of the domination of microbial rocks. 展开更多
关键词 microbial carbonate rock autochthonous DOLOMITIZATION DISSOLUTION Fengjiawan Formation Ordos Basin
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Identification of terrigenous and autochthonous organic carbon in sediment cores from cascade reservoirs in the upper stream of Pearl River and Wujiang River,southwest China:lignin phenol as a tracer
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作者 Li Gao Xin Lin +4 位作者 Jun Fan Ming Yang Xueping Chen FushunWang Jing Ma 《Acta Geochimica》 EI CAS CSCD 2022年第5期753-764,共12页
Organic carbon(OC)source attribution for cascade reservoir sediments has been identified as a critical gap in understanding the effective carbon sink of inland waters.In this study,nine sediment cores were collected f... Organic carbon(OC)source attribution for cascade reservoir sediments has been identified as a critical gap in understanding the effective carbon sink of inland waters.In this study,nine sediment cores were collected from cascade reservoirs in the Wujiang and Pearl Rivers.We analyzed lignin phenol(Λ8),total organic carbon(TOC)content,and stable carbon isotopic composition(δC)of the sediments,focusing on the changes of terrigenous OC,and the variation of OC source in cascade reservoir sediments after damming.Our results showed that theΣ8 and TOC contents decreased from upstream to downstream reservoirs,indicating the significant interception of terrigenous OC by cascade damming.Additionally,theΛ8 content in the Pearl River reservoir sediments was much higher than that in the Wujiang River.From the three-end-member mixing model,we estimated that OC in reservoir sediments mainly comes from soil and plankton.After damming,the proportion of plankton OC in TOC slightly increased in seasonal and annual regulation reservoirs due to the limnetic evolution of the reservoir.These findings suggest that the cascade damming increases the interception capacity of the river to terrigenous OC and nutrients,and that slowing of water velocity caused by damming affected primary productivity and fluvial carbon cycling. 展开更多
关键词 Cascade reservoirs Terrigenous OC LIGNIN autochthonous OC Three-end-member mixing model
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Esterase Activities and Biochemical Properties of Lactic Acid Bacteria Isolated from Goat's Milk Cheese in Argentina
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作者 Natalia Veronica Taboada Maria Soledad Lopez Alzogaray +1 位作者 Maria Claudia Abeijon Mukdsi Roxana Beatriz Medina 《Journal of Agricultural Science and Technology(B)》 2014年第9期752-760,共9页
Twenty-two lactic acid bacteria (LAB) strains isolated from Argentinean goat dairy products were evaluated for its biochemical properties and esterase activities relevant to flavor development. Streptococcus thermop... Twenty-two lactic acid bacteria (LAB) strains isolated from Argentinean goat dairy products were evaluated for its biochemical properties and esterase activities relevant to flavor development. Streptococcus thermophilus (UNSE314), Lactobacillus (L.) delbrueckii subsp, bulgaricus (UNSE309), L. rhamnosus (UNSE308), L. plantarum (UNSE287, UNSE316, UNSE317) and Pediococcus pentosaceus (UNSE315) strains presented high acidifying activity. All strains tested metabolized citrate and produced diacetyl-acetoin in goat milk. Based on these results, 10 strains with the best performance in diverse technological properties were selected to determine esterolytic activity. In all evaluated strains, esterase specific activity (ESA) was detected on ct-naphthyl (ct-NA) acetate and 13-naphthyl ([3-NA) acetate, propionate, eaprylate and ct-NA butyrate. No activity was detected on [3-NA laurate. The highest values were detected when using a-NA instead of fI-NA derivatives as substrate. In Pediocoecus strains, wide variability in ESA were observed, which were species- and strain-specific. These results allow us to select strains with biochemical properties and esterase activities to design starter and adjunct cultures that contribute to flavor development during cheese ripening, thus preserving the typical organoleptic characteristics of Argentinean goat cheeses. 展开更多
关键词 Esterase activity PEDIOCOCCUS autochthonous starter cultures biochemical properties goat's milk cheese.
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Observation and implication of the paleo-cave sediments in Ordovician strata of Well Lundong-1 in the Tarim Basin
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作者 SUN Shu ZHAO WenZhi +3 位作者 ZHANG BaoMin LIU JingJiang ZHANG Jing SHAN XiuQin 《Science China Earth Sciences》 SCIE EI CAS 2013年第4期618-627,共10页
Well Lundong-1 is located in the periclinal area on the eastern flank of the Tahe-Lunnan paleo-uplift in the Tarim Basin. A 25-m-high cave fill sequence was observed in the Upper Ordovician interval of the well at 680... Well Lundong-1 is located in the periclinal area on the eastern flank of the Tahe-Lunnan paleo-uplift in the Tarim Basin. A 25-m-high cave fill sequence was observed in the Upper Ordovician interval of the well at 6800-6825m. A third cut of cores was obtained from the top of the cave. The following conclusions were obtained by studying the cave sediments and depositional sequence, and by undertaking paleontological and elemental geochemistry analyses. 1. The cave sediments contain abundant brachiopod, gastropod, echinoderm, ostracod, and acritach fossils, which can be classified into two groups: cave autochthonous and cave allochthonous fossils (from collapse breccia dissolution or transportation by underflow). The fossils indicate that the cave was formed before the Carboniferous and partly-filled and buried during Carboniferous resubsidence. 2. Elemental geochemistry shows that the mud that filled the cave is sourced from calcareous paleo-soil and weathered crust that came from a salty environment with poor water circulation. 3. The formation and evolution of the cave occurred in three stages. The first stage occurred after the deposition of the Late Ordovician Lianglitage Formation, the second stage took place after the deposition of the Late Ordovician Sangtamu Formation, and the last stage happened after Silurian deposition. Major dissolution occurred in the latter two stages as a result of bedding-confined deep underflow karstification. Based on the reconstruction of the cave formation history, favorable paleokarst targets can be predicted and estimated to aid paleogeography and paleokarstology studies. 展开更多
关键词 cave filling and depositional sequence cave autochthonous fossils cave allochthonous fossils bedding karst Well Lundong-1 Tarim Basin
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Application of NAA and BA in Chemical Fruit Thinning of Autochthonous Cultivars of Apple
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作者 Gordana Sebek 《Journal of Agricultural Science and Technology(B)》 2014年第1期21-28,共8页
The paper presents the fruit thinning response to NAA and BA plant regulators of autochthonous cultivars of apples. The experiment was designed to evaluate NAA, over a range of concentrations (15, 20 and 30 ppm) whe... The paper presents the fruit thinning response to NAA and BA plant regulators of autochthonous cultivars of apples. The experiment was designed to evaluate NAA, over a range of concentrations (15, 20 and 30 ppm) when applied alone, and BA + NAA combinations (BA--60, 100, 120 or 140 ppm + NAA 5 ppm) for thinning the assessed apple cultivars. All the applied treatments with NAA and BA + NAA adequately thinned "Senabija" and "Ko2ara", whereas application of NAA 20 ppm and 30 ppm and combined treatment BA 140 ppm + NAA 5 ppm were effective fruit thinners for "Pasinka". In terms of the average fruit weight and number of fruits categorized as large (〉 75 mm or 〉 65 ram), as well as from the aspect of fruit number per trunk cross-sectional area, the variant of treatment BA 140 ppm + NAA 5 ppm was most effective on "Senabija" and "Paginka", whereas BA 100 ppm + NAA 5 ppm had the best effect on "Kozara". 展开更多
关键词 autochthonous cultivars naphthalene-l-acetic acid BENZYLADENINE chemical fruit thinning.
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岩石风化碳汇研究的最新进展和展望 被引量:96
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作者 刘再华 《科学通报》 EI CAS CSCD 北大核心 2012年第2期95-102,共8页
自气候变化的岩石风化控制学说提出至今,学界普遍认为,是硅酸盐的化学风化碳汇作用在控制着长时间尺度的气候变化,而在短时间尺度上硅酸盐风化碳汇与碳酸盐风化碳汇也是旗鼓相当的.然而,最新的研究发现,碳酸盐溶解的快速动力学和硅酸盐... 自气候变化的岩石风化控制学说提出至今,学界普遍认为,是硅酸盐的化学风化碳汇作用在控制着长时间尺度的气候变化,而在短时间尺度上硅酸盐风化碳汇与碳酸盐风化碳汇也是旗鼓相当的.然而,最新的研究发现,碳酸盐溶解的快速动力学和硅酸盐岩流域中微量碳酸盐矿物的风化在控制该流域溶解无机碳(DIC)浓度和碳汇上的重要性,使得碳酸盐风化碳汇占整个岩石风化碳汇的94%,而硅酸盐风化仅占6%左右.另一方面,水生光合生物对DIC的利用及其形成的有机质(内源有机碳)的埋藏,使得碳酸盐风化碳汇在任何时间尺度气候变化的控制上可能都是重要的.此外,岩石风化碳汇研究的另一重要进展是发现了碳汇随全球变暖和土地利用变化显著增加,即形成了气候变化的负反馈机制.未来应通过岩石风化碳捕获和储存过程及其控制机理的进一步研究,揭示岩石风化碳汇过程及其气候和土地利用调控潜力,以服务于各国应对气候变化的国家政策制定.重点研究:①岩石风化碳汇过程及其物理、化学和生物控制机理;②硅酸盐岩流域中微量碳酸盐矿物的风化在控制流域DIC浓度及其碳汇上的重要性;③陆地水生光合生物利用DIC产生内源有机碳的效率;④气候变化和土地利用调控岩石风化碳汇的潜力. 展开更多
关键词 碳汇 碳酸盐风化 硅酸盐风化 水生光合作用 内源有机碳 碳汇动态
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2004-2013年中国疟疾发病情况及趋势分析 被引量:87
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作者 丰俊 夏志贵 《中国病原生物学杂志》 CSCD 北大核心 2014年第5期442-446,共5页
目的分析2004-2013年7月全国疟疾发病趋势和规律,为消除疟疾工作的开展提供依据。方法利用中国疾病预防控制中心疾病监测信息报告管理系统(网络直报系统)以及全国疾病控制调查制度《疟疾防治工作调查表》(年报系统),收集2004-2013... 目的分析2004-2013年7月全国疟疾发病趋势和规律,为消除疟疾工作的开展提供依据。方法利用中国疾病预防控制中心疾病监测信息报告管理系统(网络直报系统)以及全国疾病控制调查制度《疟疾防治工作调查表》(年报系统),收集2004-2013年7月全国疟疾疫情数据资料,用Excel 2010软件进行统计分析。结果2004~2013年7月,网络直报系统共报告疟疾病例241430例,其中间日疟、恶性疟和未分型病例分别占76.54%、8.33%和15.13%;患者以男性青壮年为主;主要分布在安徽(占45.16%)、云南(占22.26%)、海南(占9.68%)、河南(占8.16%)和湖北(占4.28%)五省;临床诊断病例和实验室确诊病例分别占33.02%和66.98%;死亡病例235例,其中恶性疟占87.66%;2004~2012年,全国年报系统共报告本地感染病例204613例和输人性病例47439例,分别占81.18%和18.82%;2013年1~7月,全国网络直报系统共报告疟疾病例2987例,其中临床诊断病例占0.87%,恶性疟病例占74.89%,本地感染病例仅34例。结论全国疟疾疫情已得到有效控制,但输人性疟疾尤其是输入性恶性疟所占比例呈大幅度上升趋势。 展开更多
关键词 疟疾 本地病例 输入病例 中国
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应用Illumina MiSeq测序技术比较风干肉中细菌多样性和微生物安全性 被引量:30
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作者 田建军 张开屏 +4 位作者 杨明阳 景智波 李权威 赵丽华 靳烨 《食品科学》 EI CAS CSCD 北大核心 2019年第8期33-40,共8页
为了解风干肉制品中细菌的多样性及其微生物的安全性,采用Illumina MiSeq高通量测序技术,分析风干肉制品中细菌16S rRNA V4区基因序列,进而比较不同风干肉微生物的群落结构组成及多样性差异。结果显示,14个样品共获得466 975条有效序列,... 为了解风干肉制品中细菌的多样性及其微生物的安全性,采用Illumina MiSeq高通量测序技术,分析风干肉制品中细菌16S rRNA V4区基因序列,进而比较不同风干肉微生物的群落结构组成及多样性差异。结果显示,14个样品共获得466 975条有效序列,975个操作分类单元。多样性分析表明,自然发酵风干肉中具有高度的微生物群落多样性。微生物群落组成分析表明,自然发酵样品中厚壁菌门(Firmicutes,39%)、变形菌门(Proteobacteria,40%)、拟杆菌门(Bacteroidetes,14%)为优势菌门,所占比例都超过了10%,人工调控样品中Firmicutes(92%)为优势菌门。在自然发酵和人工调控肉制品中分别鉴定出241个和102个细菌属,细菌多样性在属的水平上差异显著(P<0.05)。研究结果加深了对风干肉细菌群落组成和多样性的认识,为保证风干肉制品的质量安全、提高风干肉制品的品质、优化风干肉的生产工艺提供理论依据。 展开更多
关键词 发酵肉制品 传统细菌群落结构 微生物安全性评价 高通量测序
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国内首起本地感染甲型H1N1流感疫情的流行病学分析 被引量:29
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作者 杨智聪 李铁钢 +14 位作者 刘于飞 吴新伟 袁俊 谢朝军 李魁彪 蒋丽云 陈艺韵 毛新武 李海麟 湛柳华 肖晓玲 刘建平 沈纪川 蔡文峰 王鸣 《中华流行病学杂志》 CAS CSCD 北大核心 2009年第7期684-686,共3页
目的分析国内首起甲型H1N1流感输入性传染源引发本地二代病例疫情,探讨发病规律和流行特征。方法设计统一调查表,采用面对面病例个案调查和现场调查,以指示病例为起点进行追踪,描述传播过程及各因素与发病之间的关系,分析疫情的流... 目的分析国内首起甲型H1N1流感输入性传染源引发本地二代病例疫情,探讨发病规律和流行特征。方法设计统一调查表,采用面对面病例个案调查和现场调查,以指示病例为起点进行追踪,描述传播过程及各因素与发病之间的关系,分析疫情的流行病学特征。结果发现指示病例后,密切接触者中有2人出现发热和上呼吸道症状且咽拭子甲型H1N1流感病毒核酸检测阳性,被确诊为国内首起本地感染甲型H1N1流感病例。2名密切接触者未采取任何防护措施与指示病例多次近距离接触,且现场通风不良;发病潜伏期37~57h,临床表现均较指示病例轻。经采取严格防疫措施,未见新发病例。结论此次事件为由输入性传染源引起的本地感染疫情,无防护近距离空气及飞沫传播为主要传播方式,空气流通不良的密闭空间是高危场所。 展开更多
关键词 甲型H1N1流感 本地感染 流行病学特征
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