全文获取类型
收费全文 | 141篇 |
免费 | 14篇 |
专业分类
林业 | 8篇 |
农学 | 2篇 |
基础科学 | 1篇 |
30篇 | |
综合类 | 12篇 |
农作物 | 14篇 |
水产渔业 | 26篇 |
畜牧兽医 | 45篇 |
园艺 | 6篇 |
植物保护 | 11篇 |
出版年
2023年 | 1篇 |
2022年 | 3篇 |
2021年 | 4篇 |
2020年 | 6篇 |
2019年 | 12篇 |
2018年 | 13篇 |
2017年 | 10篇 |
2016年 | 7篇 |
2015年 | 8篇 |
2014年 | 16篇 |
2013年 | 10篇 |
2012年 | 11篇 |
2011年 | 11篇 |
2010年 | 2篇 |
2009年 | 3篇 |
2008年 | 5篇 |
2007年 | 7篇 |
2006年 | 3篇 |
2005年 | 5篇 |
2004年 | 3篇 |
2003年 | 3篇 |
2002年 | 3篇 |
1997年 | 1篇 |
1993年 | 2篇 |
1990年 | 1篇 |
1988年 | 1篇 |
1987年 | 1篇 |
1980年 | 1篇 |
1979年 | 1篇 |
1973年 | 1篇 |
排序方式: 共有155条查询结果,搜索用时 109 毫秒
81.
Malgorzata Waleron Krzysztof Waleron Joanna Kamasa Wlodzimierz Przewodowski Ewa Lojkowska 《European journal of plant pathology / European Foundation for Plant Pathology》2011,131(2):341-354
The utility of polymorphism analysis was determined for differentiation of the following subspecies of the Gram-positive plant
pathogenic bacterium, Clavibacter michiganensis: C. m. subsp. michiganensis, C. m. subsp. sepedonicus, C. m. subsp. insidiosus C. m. subsp. nebraskensis, and C. m. subsp. tessellarius. Specific primers designed for amplification of the housekeeping genes recA, rpoB, and rpoD generated 827-, 1037-, and 862-bp DNA fragments, respectively. PCR products obtained from 40 C. michiganensis strains were analysed using RFLP with four restriction endonucleases, and those PCR products with specific RFLP patterns
were sequenced. The genotypes discriminated after PCR–RFLP were specific for each subspecies and also allowed for differentiation
of C. m. subsp. michiganensis strains. Sequence analysis of the recA, rpoB, and rpoD gene fragments also distinguished C. michiganensis subspecies and was useful for phylogenetic analysis of all subspecies. For rapid, inexpensive, and effective differentiation
of the five subspecies in this research, we recommend the amplification of recA and/or rpoD gene fragments and digestion of the PCR products with the restriction endonuclease FnuDII. 相似文献
82.
Atom transfer radical polymerization is a versatile technique for exerting precise control over polymer molecular weights, molecular weight distributions, and complex architectures. Here, we show that an externally applied electrochemical potential can reversibly activate the copper catalyst for this process by a one-electron reduction of an initially added air-stable cupric species (Cu(II)/Ligand). Modulation of polymerization kinetics is thereby tunable in real time by varying the magnitude of applied potential. Application of multistep intermittent potentials successfully triggers initiation of polymerization and subsequently toggles the polymerization between dormant and active states in a living manner. Catalyst concentrations down to 50 parts per million are demonstrated to maintain polymerization control manifested in linear first-order kinetics, a linear increase in polymer molecular weight with monomer conversion, and narrow polymer molecular weight distributions over a range of applied potentials. 相似文献
83.
Baran Agnieszka Klimkowicz-Pawlas Agnieszka Ukalska-Jaruga Aleksandra Mierzwa-Hersztek Monika Gondek Krzysztof Szara-Bąk Magdalena Tarnawski Marek Spałek Iwona 《Journal of Soils and Sediments》2021,21(6):2418-2431
Journal of Soils and Sediments - The aims of the study were to investigate the interaction between fractions of organic matter and polycyclic aromatic hydrocarbons (PAHs) in bottom sediments and to... 相似文献
84.
Krzysztof Rakus Ping Ouyang Maxime Boutier Maygane Ronsmans Anca Reschner Catherine Vancsok Joanna Jazowiecka-Rakus Alain Vanderplasschen 《Veterinary research》2013,44(1):85
Cyprinid herpesvirus 3 (CyHV-3), a member of the family Alloherpesviridae is the causative agent of a lethal, highly contagious and notifiable disease in common and koi carp. The economic importance of common and koi carp industries together with the rapid spread of CyHV-3 worldwide, explain why this virus became soon after its isolation in the 1990s a subject of applied research. In addition to its economic importance, an increasing number of fundamental studies demonstrated that CyHV-3 is an original and interesting subject for fundamental research. In this review, we summarized recent advances in CyHV-3 research with a special interest for studies related to host-virus interactions. 相似文献
85.
86.
Krzysztof Golab Jakub Gburek Bogusława Konopska Hubert Krotkiewski Maria Warwas 《Animal Science Journal》2013,84(10):702-707
Glycated proteins are considered as one of the factors involved in the pathogenesis of diabetic complications, including nephropathy. These proteins are formed endogenously under conditions of hyperglycemia, as well as being provided with food containing sugars, which was subjected to high temperature. Examples are egg products. One of the proteins found in eggs in a relatively high concentration is chicken cystatin (ovocystatin). It is now believed that some proteins can passage the intestinal epithelium by transcytosis directly into the bloodstream. Thus, glycated protein present in food can be an additional source of glycotoxins. The aim of this study was to compare the affinity of native and glycated cystatin to the brush border membranes of rat kidney. Kinetic analysis was performed with surface plasmon resonance technique using sensor chip L1. Dissociation constants for native and glycated cystatin (Kd) were 2.76 μmol/L and 3.82 μmol/L, respectively. The results of our study indicate that glycation only slightly affects binding of cystatin to brush border membranes. This suggests that glycated cystatin and other glycated proteins may also be efficiently taken up in the kidney proximal tubule. The observation may be important for understanding the mechanisms involved in the development of diabetic nephropathy. 相似文献
87.
Krzysztof Gondek Michał Kopeć Tomasz Mróz 《Communications in Soil Science and Plant Analysis》2018,49(11):1257-1265
Biochar used in this study was prepared from wheat straw and enriched with 10% solutions of chemically pure salts: ammonium sulfate [(NH4)2SO4] and magnesium sulfate (MgSO4 7H2O). The aim of this study was to determine the growth response of Perennial ryegrass L. as well as identify changes in chemical and biological properties of sandy soil after the application of biochar. A significant increase in the amount of Perennial ryegrass L. biomass was determined after amending the soil with unenriched biochar and biochar enriched with (NH4)2SO4. The highest immobilization of available forms of Mg was observed for biochar enriched with (NH4)2SO4. The highest dehydrogenase activity was determined in the soil with biochar enriched with MgSO4 7H2O. 相似文献
88.
Daniel Żarski Dariusz Kucharczyk Katarzyna Targońska Katarzyna Palińska Krzysztof Kupren Pascal Fontaine Patrick Kestemont 《Aquaculture Research》2012,43(5):713-721
This study aimed at improving the reproduction effectiveness and synchronization of ovulation in the pikeperch, Sander lucioperca (L.), during induced spawning, which is one of the main bottlenecks in the aquaculture of this species. For this purpose, a new categorization of maturation stages in pre‐ovulatory oocytes was applied. It is generally based on two morphological indicators: germinal vesicle migration or its breakdown (GVBD) and different oil droplet coalescence rates. This categorization covered seven stages (from I to VII) – from the end of vitellogenesis to ovulation. The categorization was verified by controlled reproduction with the use of hormonal stimulation (500 IU of hCG per kg of female body weight) and low spawning temperature (12 °C), which extended the latency time. In addition, some morphological indicators (pseudo‐gonadosomatic index, Fulton's condition coefficient) of females were calculated in order to determine their usability in determining the maturation stage. However, these indicators proved to be ineffective for this purpose, further highlighting the need to determine the maturational stages in pre‐ovulatory oocytes to synchronize ovulation in pikeperch. During the experiment, ovulation seemed to be synchronized among the experimental treatments. Statistical differences were found in terms of latency time between experimental groups at different maturity stages (II – 78–98 h; III – 57–78 h; IV – 48–58 h; V – 32–49 h; VI – 5–30 h) according to the proposed classification. This classification and the results presented in the study significantly improved the synchronization of ovulation, which may positively affect the effectiveness of pikeperch production under controlled conditions. 相似文献
89.
Kowalska A Zakęś Z Siwicki AK Jankowska B Jarmołowicz S Demska-Zakęś K 《Fish physiology and biochemistry》2012,38(2):375-388
The aim of the study was to determine the impact of applying different proportions of linseed (LO) and sunflower (SFO) oils
in pikeperch diets on growth, histological changes in the liver, immunological and blood chemical parameters. The fish were
fed isoenergetic and isoprotein feeds containing SFO (group 100SFO) or LO (group 100LO) in quantities of 67 g kg/feed, and
a mixture of oils: 47 g SFO and 20 g LO kg/feed (group 70SFO/30LO) and 20 g SFO and 47 g LO kg/feed (group 30SFO/70LO). Dietary
ratios of polyunsaturated fatty acids from the n-3 and n-6 series (n3/n6 index) were 0.36–2.15. Pikeperch were reared for
56 days in three replicates for each dietary treatment. Various dietary oils and ratios of n3/n6 did not impact fish growth,
feed conversion ratio, viscerosomatic and hepatosomatic index, and size of the hepatocytes. Feeding the fish high quantities
of LO and SO oils (groups 100LO and 100SFO) reduced the immunological response of the phagocytes and lymphocytes in the fish.
Moreover, this resulted in significant differences among groups in the quantity of linolenic and linoleic acid in whole fish
bodies, viscera, fillets, and livers. Various quantities of vegetable oils in the fish diets did not impact the quantity of
arachidonic, eicosapentaenoic and docosahexaenoic acid in the fillets and livers. The immunological index and low quantities
of linoleic acid in the fillets obtained in group 30SFO/70LO indicate that the n3/n6 dietary ratio of 1.35 was the most advantageous
for feeding juvenile pikeperch feeds with vegetable oils. 相似文献
90.
Piotr Gomułka Daniel Żarski Krzysztof Kupren Sławomir Krejszeff Katarzyna Targońska Dariusz Kucharczyk 《Aquaculture International》2014,22(1):225-233
Acute ammonia toxicity was investigated in four developmental stages of the juvenile ide, Leuciscus idus: 1, 10, 20 and 30 days after the first feeding. Mean (±SD) total length of the larvae was 8.5 ± 0.3, 15.7 ± 0.7, 23.0 ± 2.0 and 29.7 ± 2.0 mm, and standard weight was 1.6 ± 0.3, 9.2 ± 5.5, 94.9 ± 31.0 and 196.0 ± 31.7 mg, respectively. The larvae used for toxicity tests were reared in the experimental, closed recirculating system. Groups of fishes (n from 7 to 10; in respect of fish size) were exposed to the ammonium chloride solutions in 1-L glass units. Water temperature was 25 ± 0.1 °C for both the rearing and the toxicity tests. pH was not adjusted and ranged between 8.4 and 8.7. The ammonium chloride solutions were renewed every 12 h. At the same time, dead larvae were counted and removed, and the pH and temperature measurements were taken. Each acute toxicity test duration was 96 h, and lethal concentration LC1, LC50 and LC99 values were calculated for 24, 48, 72 and 96 h. The susceptibility of the ide larvae to ammonia decreased linearly with age up to 20th day and surprisingly increased during the next 10 days. The LC50 (48 h) values ranged from 0.27 mg L?1 of unionized ammonia nitrogen for 1 day after the first feeding (AFF) larvae to 1.42 mg L?1 at day 20 after first feeding. The LC50 (48 h) for 30 days AFF was as high as 0.67 mg L?1. The critical level of the unionized ammonia nitrogen for ide larvae was suggested as 0.21 mg L?1. 相似文献