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黄渤海沿岸污损生物中的苔藓虫 总被引:1,自引:0,他引:1
从1974年8月至1985年6月在黄渤海沿岸9个港湾进行了污损生物挂板实验,同时调查了船只、码头、浮标等水下设施的污损生物,共获得992号苔藓虫标本。经鉴定有35种,分别属于3目17科,它们大部分是我国沿岸水域的广分布种,有些是印度—西太平洋暖水种。在长江口外吕泗洋水文平台发现4种,连云港17种,烟台港18种,蓬莱港12种,渤海海峡的砣矶岛8种,塘沽新港14种,族顺港15种,丹东港是鸭绿江下游河港,未发现苔藓虫。 黄渤海苔藓虫主要附着季节6—10月,高峰期7、8、9三个月。 文章最后论述了苔藓虫作为污损生物主要成员之一在污损生物中的意义。 相似文献
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四个类群海洋蛭弧菌类生物生长特性的比较 总被引:1,自引:0,他引:1
研究了噬菌弧菌科(Bacteriovoracaceae) 4个类群共12株海洋蛭弧菌类生物(Bdellovibrio- and-like organisms, BALOs)的生长温度和盐度范围及其对6种常见对虾病原弧菌的裂解能力, 并通过透射电镜分析了其中4个代表菌株的形态特征。结果表明, 同一群或亚群内菌株的生长温度或盐度相同, 即类群IV、VI、IX、X菌株的生长温度范围分别为20°C~35°C、15°C~35°C、15°C~ 40°C和10°C~40°C, 最适生长温度为30°C或35°C; 生长盐度范围分别为5‰~40‰、2.5‰~30‰、5‰~60‰和5‰~60‰, 最适生长盐度分别为10‰、5‰、20‰和20‰。测试的6种弧菌中有3种可被全部BALOs裂解, 而其它弧菌仅被部分BALOs裂解, 但即使同一类群菌株, 对某些弧菌也表现不同的裂解能力。形态上, 4株不同类群BALOs均呈典型的弧状细胞, 具极生单鞭毛。 相似文献
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温度和盐度对缢蛏浮游幼虫发育的影响 总被引:15,自引:1,他引:14
本文叙述了在室内控制条件下,温度和盐度单因子及其结合对缢蛏浮游幼虫的影响。缢蛏浮游幼虫生长发育的适温范围为17°—32℃,其中以25°—27℃为最好。对高温和低温有较强的耐力,致死温度的上限为40℃左右,变态的下限水温为15℃左右,幼虫适盐范围是4.50—28.30‰,其中以12.40‰为最适宜,但幼虫对低盐度的耐力比对较高盐度的耐力强。 温度对缢蛏浮游幼虫期的长短、增长速度和存活率的影响,要比盐度对它的影响显著,而盐度对缢蛏幼虫变态率的影响却比温度重要些。温度与盐度对缢蛏浮游幼虫发育影响的相关性不明显。 相似文献
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环境因子对大亚湾人工鱼礁上附着生物分布的影响 总被引:4,自引:0,他引:4
通过对深圳大亚湾人工鱼礁区7个月(2008-04~2008-10)挂板实验,同时监测相应的环境因子指标.以附着生物丰度数据进行了除趋势对应分析(DCA),并根据附着生物丰度数据和7个环境因子进行了典范对应分析(CCA).共鉴定出附着生物54种,物种鉴定结果表明实验试板上的常见种有华美盘管虫 (Hydroides elegans)、三角藤壶( Balanus trigonus)、细肋肌蛤(Musculus mirandus)等.DCA种类排序图可明显地看出每种附着生物都有自己的分布中心和分布区域;CCA分析结果表明深度、透明度、溶解氧是影响附着生物群落变化的最主要环境因子,其次是盐度和温度.CCA排序图较好地反映了人工鱼礁上附着生物分布与各环境因子的相互关系. 相似文献
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玫瑰茄(Hibiscus sabdariffa)系一年生草本的短日照植物,产于印度至马来西亚一带。生长在以色列(北纬32°)的玫瑰茄,其最早的成花时间为8月5日。初步研究表明,营养生长和生殖生长秋季就停止,这可能是受夜间低温影响所致。本文旨在探明玫瑰茄不同生长阶段对冷害的敏感性。 将栽种在塑料盆钵的植株分别置于14—30℃的温室内,光周期平均为10小时,每2—3天浇水一次,不施肥。在一定的生长阶段,以10株为一组移入25°、17°、14°或10℃±2℃的生长室里,并采用冷—白莹光照,每日光周期为8小时。三个生长阶段为:1. 相似文献
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1998~1999年春秋季渤海中部及其邻近海域叶绿素a浓度及初级生产力估算 总被引:18,自引:3,他引:18
根据 1 998年 9月和 1 999年 4月两次调查研究表明 :1 998年秋季 ,调查区 (37°N~ 41°N,1 1 7.5°E~1 2 2 .5°E)表层叶绿素 a浓度介于 0 .0 4 6~ 5.885 mg/ m3,平均为 1 .892 mg/ m3;1 999年春季介于 0 .1 70~8.0 92 mg/ m3,平均为 1 .62 1 mg/ m3。叶绿素 a的平面分布与历史资料相近月份的分布趋势基本一致 ,调查区南部是整个调查海区的高值区 ,而西部及渤海海峡在不同时期出现过高值 ,中央海区叶绿素 a的浓度都比较低。叶绿素 a浓度剖面分布在春季是从调查区西部、渤海中部到渤海海峡依次增高 ,而秋季刚好相反 ;从调查区南部、渤海中部到北部的变化趋势在春季和秋季都是依次降低的。在连续站进行的现场测量碳同化数介于 0 .2 63~ 4.649mg C/ (mg Chla· h)之间 ,平均值为 1 .91 6 mg C/ (mg Chla· h)。 1 998年秋季 ,调查区水柱初级生产力介于 1 0 .1~ 458.3 mg C/ (m2· d) ,平均为 1 63.6 mg C/ (m2· d) ,初级生产力的高值区位于海峡口附近。1 999年春季 ,介于 64.9~ 740 .6mg C/ (m2· d) ,平均为 32 3.7mg C/ (m2· d) ,初级生产力的高值区位于海峡口附近和黄河口附近。同历史资料相比 ,初级生产力有所下降。观测和模型的结果表明 ,渤海浮游植物生物量的分布与水文条件密切相关 ,而初 相似文献
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渤海线虫群落的多样性及中性模型分析 总被引:19,自引:2,他引:17
对渤海的黄河口水下三角洲、莱州湾和渤海中部共9个站位的海洋线虫群落的多样性进行了研究.用于比较的海域和站位还包括1995年胶州湾的95B2站和1988年湄州湾的A01站.以上11个站位共鉴定出自由生活海洋线虫154种,分属于107属29个科.使用种丰度(SR),香农-维弗指数(H′)和均衡度(J)用来比较不同生境的生物多样性.不同生境和站位的生物多样性水平由高到低依次为渤海中部(9761、DA18、DA19和DA20,SR=8.60±0.84,H′=4.94±0.23)、莱州湾(9762、DA2和DA4,SR=6.48士0.40,H′=3.95±3.0)和黄河口水下三角洲(E9和E11,SR=4.18±0.56,H′=3.60±0.24).线虫生物多样性与海水的盐度和沉积物的异质性指数(h)呈显著的负相关(P≤0.01).Caswell
中性模型分析指明,大部分研究站位的"V"值为"-2~+2",说明未受到显著外界因子的扰动.渤海中部的9761站的"V"值为2.054,暗示环境稳定性的增强,而莱州湾的DA4站"V"值为-2.624指明受到外界环境因子的显著影响,可能与黄河口输送大量的物质有关. 相似文献
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A new polynitro cage compound 2, 4, 6, 8, 10, 12, 13, 14, 15-nonanitro-2, 4, 6, 8, 10, 12, 13, 14, 15-nonaazaheptcyclo [5.5.1.1(3,11).1(5,9)] pentadecane (NNNAHP) was designed in the present work. Its molecular structure was optimized at the B3LYP/6-31 G(d,p) level of density functional theory (DFT) and crystal structure was predicted using the Compass and Dreiding force fields and refined by DFT GGA-RPBE method. The obtained crystal structure of NNNAHP belongs to the P-1 space group and the lattice parameters are a = 9.99 ?, b = 10.78 ?, c = 9.99 ?, α = 90.01°, β = 120.01°, γ = 90.00°, and Z = 2, respectively. Based on the optimized crystal structure, the band gap, density of state, thermodynamic properties, infrared spectrum, strain energy, detonation characteristics, and thermal stability were predicted. Calculation results show that NNNAHP has detonation properties close to those of CL-20 and is a high energy density compound with moderate stability. 相似文献
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Summary Concentration of N, P, K, Ca, Mg and S in summer groundnut crop was higher than in kharif while Zn, Fe, Mn and Cu contents were higher in summer crop. Kernel's N, P and Zn; Leaflet's Ca and Mn; Stem's K and Fe; Root's S and Cu and Petiole's Mg contents were highest. Shell's N, P, K, Mg, S, Zn and Cu; Kernel's Ca, Fe and Mn contents were the least. N, P, K, S, Zn and Cu concentrations decreased linearly as the crop grew. Ca, Mg, Fe and Mn concentrations did not display any distinct pattern. Ca concentration was positively correlated with pod yield in both the seasons. 相似文献
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The variation with age of the 18 trace element mass fractions and some histological characteristics of intact prostate glands of 50 subjects aged 0–30 years was investigated by instrumental neutron activation analysis, inductively coupled plasma atomic emission spectrometry, and a quantitative morphometric analysis. Mean values ± standard error of the mean (M ± SΕΜ) for the mass fractions (in milligrams per kilogram wet tissue) of these trace elements in pre-puberty were: Al 28.5 ± 9.0, B 0.40 ± 0.11, Ba 1.48 ± 0.44, Br 10.5 ± 1.5, Ca 241 ± 30, Cl 3,203 ± 278, Cu 3.51 ± 0.89, Fe 33.7 ± 4.1, K 2,364 ± 145, Li 0.020 ± 0.004, Mg 153 ± 23, Mn 0.46 ± 0.06, Na 2,286 ± 130, P 1,391 ± 100, S 1,698 ± 132, Si 62 ± 11, Sr 0.38 ± 0.08, and Zn 27.6 ± 2.3. During puberty and postpuberty, when there is a significant increase in circulating androgens, the mean values were: Al 7.2 ± 1.4, B 0.21 ± 0.05, Ba 0.25 ± 0.06, Br 5.8 ± 1.0, Ca 433 ± 81, Cl 2,314 ± 201, Cu 1.77 ± 0.13, Fe 20.9 ± 1.6, K 2,585 ± 118, Li 0.0088 ± 0.0014, Mg 232 ± 27, Mn 0.34 ± 0.04, Na 1,875 ± 107, P 1,403 ± 98, S 1,673 ± 73, Si 22.2 ± 3.1, Sr 0.22 ± 0.03, and Zn 93.3 ± 8.9. Mean values (M ± SΕΜ) of percent volumes (%) of the stroma, epithelium and lumen in the prostate before puberty were 73.4 ± 2.6, 20.4 ± 1.7, and 4.45 ± 0.94, respectively, versus 46.5 ± 2.5, 38.5 ± 1.9, and 14.9 ± 1.2 during puberty and postpuberty. This work’s results confirm that the Zn mass fraction in prostate tissue is an androgen-dependent parameter. For the first time it has been demonstrated that the glandular lumen is a main pool of Ca, Mg, and Zn accumulation and that the stroma is a main pool of Al, B, Ba, Br, Cl, Cu, Fe, Mn, Na, and Si accumulation in the normal human prostate, for the age range 0–30 years. It was concluded that the Ca, Mg, and Zn binds tightly within the prostatic fluid, because the volume of glandular lumen reflects the volume of prostatic fluid. 相似文献
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The goal of this article was to establish reference ranges of the concentration of trace elements in human serum and to compare
these results with those reported by other authors. We describe the sample preparation and measurement conditions that allow
the rapid, precise, and accurate determination of Al, As, B, Be, Cd, Co, Cu, Fe, Li, Mn, Mo, Ni, Rb, Se, Sr, and Zn in human
serum samples (n=110) by inductively coupled plasma-mass spectrometry (ICP-MS). Accuracy and precision were determined by analyzing three
reconstituted reference serum samples by comparison with other methods and by the standard addition procedure.
The advantages of the ICP-MS method include short time of analysis of the elements mentioned, low detection limit, high precision,
and high accuracy. Disadventages include a high risk of contamination due to the presence of some of the elements of interest
in the environment, the relatively delicate sample handling, and the high cost of the equipment. 相似文献
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G. V. Iyengar 《Biological trace element research》1987,12(1):263-295
This report attempts to formulate reference ranges of elemental concentrations for 15 trace elements in selected human tissues
and body fluids.
A set of samples consisting of whole blood, blood serum, urine, milk, liver, and hair were chosen and considered for 15 elements
of biological significance: As, Cd, Co, Cr, Cu, F, Fe, I, Hg, Mn, Mo, Ni, Pb, Se, and Zn. The results represent wholly or
partially data received from 40 countries of the global regions of Africa, Asia, Europe, North, South, and Central America,
Australia, and New Zealand.
This survey, even if qualitative, has been useful in demonstrating certain trends of trace-element scenarios around the world.
It is of course recognized that both diet and environment exert a strong influence on the distribution pattern of several
elements, such as As, Cd, Mn, Pb, Se, and Zn. A limited comparison of the available information on soil status of different
countries reflected some interesting associations for elements, such as Mn and Zn.
Importantly, this study revealed that only a few countries were in a position to identify a reasonable amount of data on samples
requested for this project. Regretably, for a number of countries, any dependable data for even such essential elements as
Cu, Fe, and Zn were not available.
In view of the nutritional importance of many elements, the time is ripe for concerted efforts by intergovernmental agencies
to initiate investigations or commission task forces/projects to generate reliable reference data for selected global regions,
which sadly lack data of any kind at present. 相似文献
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Vladimir Zaichick Sofia Zaichick Vasilii Karandashev Sergey Nosenko 《Biological trace element research》2009,129(1-3):107-115
The effect of age and gender on major, minor, and trace element contents in the intact rib bone of 80 relatively healthy 15–55-year-old women and men was investigated. Contents or upper limit of contents of 16 chemical elements in the rib bone were determined by inductively coupled plasma atomic emission spectrometry (ICP-AES). Mean values (M?±?SΕΜ) for the mass fraction of Ba, Ca, Cu, Fe, K, Li, Mg, Na, P, S, Sr, and Zn (milligram per kilogram of dry bone) were as follows: 2.54?±?0.16, 171,400?±?4,050, 1.35?±?0.22, 140?±?11, 1,874?±?71, 0.049?±?0.011, 2,139?±?38, 5,378?±?88, 75,140?±?1,660, 1,881?±?51, 291?±?20, and 92.8?±?1.5, respectively. The upper limits of contents of Al, B, Mn, and V were <7.20, <0.65, <0.36, and <0.03, respectively. Statistically significant tendency for the Ca, Mg, and P content to decrease with age was found in the human rib bone, regardless of gender. The mass fraction of Fe in the male rib bone increases with age. It was shown that higher Ca, Mg, Na, P, and Sr mass fractions as well as lower Fe content were typical of female ribs as compared to those in male ribs. 相似文献
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Oral cancer is one of the main causes of cancer-related deaths in South-Asian countries. There are very limited treatment options available for oral cancer. Research endeavors focused on discovery and development of novel therapies for oral cancer, is necessary to control the ever rising oral cancer related mortalities. We mined the large pool of compounds from the publicly available compound databases, to identify potential therapeutic compounds for oral cancer. Over 84 million compounds were screened for the possible anti-cancer activity by custom build SVM classifier. The molecular targets of the predicted anti-cancer compounds were mined from reliable sources like experimental bioassays studies associated with the compound, and from protein-compound interaction databases. Therapeutic compounds from DrugBank, and a list of natural anti-cancer compounds derived from literature mining of published studies, were used for building partial least squares regression model. The regression model thus built, was used for the estimation of oral cancer specific weights based on the molecular targets. These weights were used to compute scores for screening the predicted anti-cancer compounds for their potential to treat oral cancer. The list of potential compounds was annotated with corresponding physicochemical properties, cancer specific bioactivity evidences, and literature evidences. In all, 288 compounds with the potential to treat oral cancer were identified in the current study. The majority of the compounds in this list are natural products, which are well-tolerated and have minimal side-effects compared to the synthetic counterparts. Some of the potential therapeutic compounds identified in the current study are resveratrol, nimbolide, lovastatin, bortezomib, vorinostat, berberine, pterostilbene, deguelin, andrographolide, and colchicine. 相似文献