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451.
从近岸海水养殖环境中分离获得一株能高效降解氯氰菊酯(Cypermethrin,CYP)和溴氰菊酯(Deltamethrin,DEL)的菌株HS-10,经生理生化和16S rDNA分析,初步鉴定其为假交替单胞菌(Pseudoalteromonas sp.)。不同降解条件下的实验结果表明,菌株HS-10在pH 7.0、温度28°C的环境中具有较好的生长和降解效率,在该条件下,对初始浓度为100mg/L的CYP和DEL的降解效率分别为75.6%和90.9%。进一步采用发光细菌和核磁共振(NMR)方法对菌株HS-10的降解产物进行分析,结果表明,CYP和DEL主要通过微生物降解消除,其降解产物的毒性显著降低。同时,考察了菌株HS-10对氯氰菊酯、溴氰菊酯、联苯菊酯(BIF)、氟氯氰菊酯(CYF)和氰戊菊酯(FEN)5种拟除虫菊酯类农药(浓度分别为100mg/L)的降解效率,结果表明,对5种农药的降解率均达到50%以上,本研究获得的菌株HS-10可用于海水养殖环境中拟除虫菊酯类农药残留污染的生物修复。 相似文献
452.
采用响应面法对1株高产卡拉胶酶的印度尼西亚热泉菌Bacillus sp.Lc50-1的发酵条件进行优化。分别以培养温度、pH值、C源、N源、金属离子及接种量作为唯一变量进行单因素实验,筛选出对酶活有显著影响的单因素取值范围;参考单因素实验结果,再利用Box-Behnken设计及响应面分析法进行回归分析以确定最佳发酵条件。结果表明,培养温度、卡拉胶浓度(C源)、蛋白胨浓度(N源)、KCl浓度(金属离子)与酶活存在着显著的相关性,通过求解回归方程得到Bacillus sp.Lc50-1的最佳发酵条件为:培养温度47.5℃、蛋白胨0.25%、卡拉胶0.3%、KCl 21.55mmol·L-1,优化后发酵上清液的酶活达到8.9U·mL-1,比优化前提高了1.5倍。 相似文献
453.
Eighteen agar media were tested for the culture of gut-associated bacteria from farmed adult turbot(Scophthalmus maximus),including 16 agar media with or without 1% gastrointestinal(GI)supernatant,or with 2% or 4% GI supernatant.A total of 1 711 colonies were analyzed and 24 operational taxonomic units(OTUs)were identifi ed.The greatest bacterial diversity was isolated on Zobell 2216E/Zobell 2216E+ agar media,whereas MRS/MRS+ agar media produced a low diversity of colonies.Agar media with GI supernatant(1%,2%,or 4%)showed increased diversity and yielded different profi les of OTUs from the corresponding original media,suggesting that GI supernatant provides substances that enhance the culture effi ciency of bacteria from the turbot GI tract.The large majority of the colonies(82%)were γ-Proteobacteria,whereas 15.6% and 2.4% of colonies were Firmicutes and Actinobacteria,respectively.At the genus level,49.4% of all colonies were assigned to Vibrio.Other potential pathogens,including Pseudomonas,Photobacterium,and Enterobacter,and potential probiotics,including Bacillus,Paenibacillus,and Pseudomonas,were also isolated on agar media.Most cultured bacteria belonged to species that were fi rst described in the turbot GI tract.The impact of these species on turbot physiology and health should be investigated further. 相似文献
454.
Fluorescence in-situ hybridization (FISH) and 16S rRNA gene clone library analyses were used to determine the abundance and diversity of archaea in Prydz Bay, Antarctica. Correlation analysis was also performed to assess links between physicochemical parameters and archaeal abundance and diversity within the sea-ice. Samples of sea-ice and seawater were collected during the 26th Chinese National Antarctic Research Expedition. The results of FISH showed that archaea were relatively abundant within the top layer of the sea-ice, and correlation analysis suggested that the concentration of 4NH+ might be one of the main factors underlying this distribution pattern. However, using 16S rRNA gene libraries, archaea were not detected in the top and middle layers of the sea-ice. All archaeal clones obtained from the bottom layer of the sea-ice were grouped into the Marine Group I Crenarchaeota while the archaeal clones from seawater were assigned to Marine Group I Crenarchaeota, Marine Group II Euryarchaeota, and Marine Group III Euryarchaeota. Overall, the ifndings of this study showed that the diversity of archaea in the sea-ice in Prydz Bay was low. 相似文献
455.
《青岛海洋大学学报(英文版)》2014,(2):249-256
The dynamic microcosms were used to evaluate the effect of oil spills on microbial ecological system in marine sedi- ment and the enhancement of nutrient on the oil removal. The function and structure of microbial community caused by the oil pollu-tion and phosphate dosage were simultaneously monitored by dehydrogenase activity assay and PCR-denaturing gradient gel elec- trophoresis (DGGE) techniques. The results indicated that the amount of total bacteria in all dynamic microcosms declined rapidly with incubation time. The number of petroleum-degrading bacteria and the activity of sediment dehydrogenase were gradually en-hanced by petroleum in the oil-treated microcosms, while they both showed no obvious response to phosphate dosage. In comparison, phosphate spiked heterotrophic bacteria and they showed a significant increase in amount. DGGE profiles indicated that petroleum dosage greatly changed community structure, and the bacteria belonged to class Deltaproteobacteria, and phyla Bacteroidetes and Chlorobi were enriched. This study demonstrated that petroleum input greatly impacted the microbial community structure and con- sequently the marine sediment petroleum-degrading activity was enhanced. Phosphate dosage would multiply heterotrophic bacteria but not significantly enhance the petroleum degradation. 相似文献
456.
MA Yuexin SUN Feixue ZHANG Congyao BAO Pengyun CAO Shuqing ZHANG Meiyan 《青岛海洋大学学报(英文版)》2014,(6):1061-1066
A marine bacterium,Pseudoalteromonas sp.BC228 was supplemented to feed in a feeding experiment aiming to determine its ability of enhancing the digestive enzyme activity and immune response of juvenile Apostichopusjaponicus.Sea cucumber individuals were fed with the diets containing 0 (control),105,107 and 109 CFU g-1 diet of BC228 for 45 days.Results showed that intestinal trypsin and lipase activities were significantly enhanced by 107 and 109 CFU g-1 diet of BC228 in comparison with control (P〈0.01).The phagocytic activity in the coelomocytes of sea cucumber fed the diet supplemented with 107 CFUg-1 diet of BC228 was significantly higher than that of those fed control diet (P〈0.05).In addition,105 and 107 CFUg-1 diet of BC228 significantly enhanced lysozyme and phenoloxidase activities in the coelomic fluid of sea cucumber,respectively,in comparison with other diets (P 〈 0.01).Sea cucumbers,10 each diet,were challenged with Vibrio splendidus NB 13 after 45 days of feeding.It was found that the cumulative incidence and mortality of sea cucumber fed with BC228 containing diets were lower than those of animals fed control diet.Our findings evidenced that BC228 supplemented in diets improved the digestive enzyme activity of juvenile sea cucumber,stimulated its immune response and enhanced its resistance to the infection of V.splendidus. 相似文献
457.
正3月4日,河南省委常委、纪委书记尹晋华,省纪委常委、秘书长侯玉林等,到荥阳市国土资源局调研党风廉政建设工作。近年来,荥阳市国土资源局以十八大精神为指导,以积极构建惩治和预防腐败体系为重点,深入推进党风廉政建设工作扎实开展,巩固落实贯彻中央八项规定的成果,坚决纠正"四风"问题,以多种形式创新廉政宣传教育模式,打造"九个一"廉政文化品牌,并取得了明显成绩。 相似文献
458.
通过同源引物从致病性哈维氏弧菌(Vibrio harveyi)ZJ0603基因组中克隆GST的开放阅读框(ORF),构建真核表达质粒pcDNA-GST。大量抽提重组质粒后,于背鳍基部肌肉注射重组质粒免疫斜带石斑鱼(Epinephelus coioides),分析重组质粒的免疫效果。通过核酸水平检测重组质粒在鱼体肝、肌肉、头肾和脾脏组织的分布;用ELISA法检测鱼体血清的抗体水平,用Western-blot检测目的蛋白的表达情况。结果表明:该序列全长615 bp;免疫7 d后,鱼体中均有质粒分布;斜带石斑鱼血清中产生抗GST的高效抗体(1∶4 096);相应的目的蛋白也在鱼体中成功表达。攻毒后,疫苗免疫保护率达80%,表明GST可作为防治哈维氏弧菌病有效候选抗原。 相似文献
459.
鱼类诺卡氏菌病是全球性的鱼病,杀鲑诺卡氏菌(Nocardia salmonicida)是引起鱼类诺卡氏菌病的主要病原之一。根据杀鲑诺卡氏菌16S-23S转录间隔区(ITS)序列设计引物,建立特异性PCR检测杀鲑诺卡氏菌的方法。结果表明,筛选的PCR引物可特异性地扩增出杀鲑诺卡氏菌的ITS片段,检测灵敏度(DNA浓度)为28.3 pg·μL-1。检测人工感染杀鲑诺卡氏菌的鱼组织,结果显示,该方法可从未分离到病原菌的病鱼组织中检出阳性片段,较传统细菌分离鉴定方法更为高效灵敏。 相似文献
460.