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排序方式: 共有268条查询结果,搜索用时 15 毫秒
101.
Noha Mansour 《Journal of plant nutrition》2016,39(4):443-455
A pot experiment was carried on ‘Manzanillo’ olives transplants included three levels of nitrogen (N) (N1=25, N2=50 and N3=75 g N plant?1 year?1) and four levels of cobalt (Co) (B1=zero, B2=10, B3=20 and B4=30 ppm Co). Generally, fertilizing with 50 g N plant?1 year?1 gave the highest significant value than those of other treatments in all vegetative growth characters. Vegetative growth was gradually increased by increasing cobalt up to 20 ppm and 30 ppm levels. Regarding the combination between nitrogen and cobalt levels in most cases, the best treatment was N2 x B3, which gave the highest values of vegetative growth characters. The combinations of nitrogen and cobalt created slightly more variable and increased effects on the macro and micronutrient contents of ‘Manzanillo’ olives transplants. 相似文献
102.
Ali AI-MAKTOUMI ;Said A-ISMAILY ;Anvar KACIMOV ;Hamed AI-BUSAIDI ;Said AI-SAQRI ;Mansour AI-HADABI 《干旱区科学》2014,(6):690-703
Interaction between soil pedogenesis, subsurface water dynamics, climate, vegetation and human ingenuity in a desert environment has been found to result in a unique ecohydrological system with an essentially three dimensional sedimentation structure in the bed of a recharge dam in Oman. A 3-D array of silt blocks sandwiched by dry sand-filled horizontal and vertical fractures was studied in pot experiments as a model of a natural prototype. Pots are filled with a homogenous sand-silt mixture(control) or artificially structured(smart design, SD) soil substrates. Rhodes grass and ivy(Ipomea, Convolvulaceae) were grown in the pots during the hottest season in Oman. Soil moisture content(SMC) was measured at different depths over a period of 20 days without irrigation. SD preserved the SMC of the root zone for both ivy and grass(SMC of around 25%–30% compared to 10% for control, 3 days after the last irrigation). Even after 20 days, SMC was around 18% in the SD and 7% in the control. This, similar to the case of a natural prototype, is attributed to the higher upward capillary movement of water in control pots and intensive evaporation. The capillary barrier of sand sheaths causes discontinuity in moisture migration from the micro-pores in the silt blocks to sand pores. The blocks serve as capillarity-locked water buffers, which are depleted at a slow rate by transpiration rather than evaporation from the soil surface. This creates a unique ecosystem with a dramatic difference in vegetation between SD-pots and control pots. Consequently, the Noy-Meir edaphic factor, conceptualizing the ecological impact of 1-D vertical heterogeneity of desert soils, should be generalized to incorporate 3-D soil heterogeneity patterns. This agro-engineering control of the soil substrate and soil moisture distribution and dynamics(SMDaD) can be widely used by desert farmers as a cheap technique, with significant savings of irrigation water. 相似文献
103.
Banebaghi is considered a natural hybrid in Pistacia genus that can be used as rootstock for pistachio. In order to study the effects of salinity stress on growth indices, physiological parameters and element concentration in Banebaghi, an experiment was arranged as a factorial in completely randomized design (CRD). Factors were salinity of irrigation water (0, 60 and 120 mM of sodium chloride, calcium chloride, magnesium chloride, respectively), growth type (mutica growth type and pistachio growth type) and stem height (stem height lower half of the plant and stem height upper half of the plant) with four replications. Our results showed that salinity reduced vegetative parameters, SPAD index, leaf relative water content (RWC) and water use efficiency (WUE). Shoot dry weight of seedlings in both heights, decreased at the salinity level of 120 mM, at about 60% compared with control. At the highest level of salinity (120 mM), seedlings with a height lower half of the plant had lower reduction in the fresh and dry weight of the root and showed more resistance to the salinity stress because of maintaining RWC of leaves and high levels of potassium and calcium in the shoot. Salinity increased sodium (Na) concentration of shoot and root in both growth types: mutica and pistachio. Seedlings with pistachio growth type and a height upper half of the plant and seedlings with mutica growth type and a height lower half of the plant had more resistance to salinity stress. 相似文献
104.
105.
In this study a newly laser treatment method for surface modification of nanofibers is introduced. The new method is based
on different infrared absorption of materials. Surface modification of Clay-PAN composite nanofibers was performed using selective
laser etching approach with CO2 pulsed laser in order to increase surface area of nanofibers. The surface structure of resulted nanofibers is characterized
using field emission scanning electron microscope and the results show characteristic modification of the surface topography
of laser treated nanofibers. The modified surface structure of nanofibers was studied and analyzed for different laser pulse
numbers and laser fluence. The results show that nanofiber surface modification strongly depends on the number of CO2 laser pulses and frequency of modified sites on the surface of nanofibers increasing with increasing the pulse fluence. This
new technique is highly selective and can also compete with conventional techniques for nanofibers surface modification. 相似文献
106.
M. Mansour 《Journal of pest science》2010,83(3):243-249
The sensitivity of the Mediterranean flour moth, Ephestia kuehniella, eggs in different stages of development to gamma irradiation was studied and the acceptability of irradiated eggs by Trichogramma cacoeciae females was examined. Eggs ranging in age from 1–24 to 49–72 h were exposed, at 24 h intervals, to gamma radiation dosages
ranging from 25 to 400 Gy and effects of gamma radiation on egg hatch and adult emergence was investigated. In addition, the
developmental rate of immature stages (larvae and pupae), resulting from irradiated eggs, to the adult stage was examined
and the acceptance of irradiated eggs to T. cacoeciae females was evaluated. Results showed that the radio-sensitivity of E. kuehniella eggs decreased with increasing age. Egg hatch in 1–24-h-old eggs was significantly affected at 25 Gy dose and at 75 Gy dose,
no egg hatch was observed. When irradiating 25–48-h-old eggs, however, egg hatch was less than 5% at 100 Gy dose, and eggs
49–72-h-old were more resistant; 50 Gy had no significant effect on egg hatch and 300 Gy did not completely prevent it. Irradiation
also negatively affected survival to the adult stage. When 25–48-h-old eggs were irradiated, survival to the adult stage was
completely prevented at 75 Gy dose and no survival was observed beyond 100 Gy dose in 49–72-h-old eggs. In addition, the rate
of development of immature stages resulting from irradiated eggs was negatively affected. While more than 97% of control moths
emerged within 30 days, this ratio decreased to 53 and 69% in 1–24 and 25–48-h-old eggs exposed to 25 Gy dose. Furthermore,
irradiation positively affected the degree of acceptance of eggs to parasitization; irradiated eggs (≤49-h-old) were more
acceptable to T. cacoeciae than cold-treated ones. 相似文献
107.
Lamiaa A. Shaala Diaa T. A. Youssef Jihan M. Badr Mansour Sulaiman Alaa Khedr 《Marine drugs》2015,13(4):1621-1631
In a continuation of our efforts to identify bioactive compounds from Red Sea Verongid sponges, the organic extract of the sponge Suberea species afforded seven compounds including two new dibrominated alkaloids, subereamollines C and D (1 and 2), together with the known compounds aerothionin (3), homoaerothionin (4), aeroplysinin-1 (5), aeroplysinin-2 (6) and a revised subereaphenol C (7) as ethyl 2-(2,4-dibromo-3,6-dihydroxyphenyl)acetate. The structures of the isolated compounds were assigned by different spectral data including optical rotations, 1D (1H and 13C) and 2D (COSY, multiplicity-edited HSQC, and HMBC) NMR and high-resolution mass spectroscopy. Aerothionin (3) and subereaphenol C (7) displayed potent cytotoxic activity against HeLa cell line with IC50 values of 29 and 13.3 µM, respectively. In addition, aeroplysinin-2 (6) showed potent antimigratory activity against the human breast cancer cell line MDA-MB-231 with IC50 of 18 µM. Subereamollines C and D are new congeners of the previously reported compounds subereamollines A and B with methyl ester functionalities on the side chain. These findings provide further insight into the biosynthetic capabilities of members of the genus Suberea and the chemical diversity as well as the biological activity of these compounds. 相似文献
108.
Shirin Karimi Abdolreza Mohamadnia Seyed Alireza Nadji Reza Yadegarazari Adnan Khosravi Naghmeh Bahrami Massoud Saidijam 《Iranian Biomedical Journal》2015,19(1):17-22
Introduction: Although extensive research has been conducted on lung cancer markers, a singular clinically applicable marker has not been found yet. The objective of this study was to evaluate the sensitivity and the specificity of carcinoembryonic antigen (CEA) mRNA and lung-specific X protein (LUNX) mRNA biomarkers in peripheral blood to detect lung cancer individually and simultaneously. Methods: Thirty patients affected by lung cancer and 30 healthy individuals were studied in this research. Three vials of cDNA were made from each sample after taking peripheral blood samples and extracting total RNA. Each sample was examined by the real-time RT-PCR technique. The result from each vial was then compared with the sensitivity of overall marker. Results: The CEA mRNA was positive in 24 out of 30 lung cancer patients. Hence, its sensitivity was determined at 80%, differing significantly from that observed in healthy individuals, where 11 positive cases were seen. The overall sensitivity of this marker was significantly associated with positivity in vials 2 and 3 but not in vial 1. The LUNX mRNA was positive in 21 out of 30 patients, indicating 70% sensitivity. This finding significantly differed from that in healthy individuals. The overall sensitivity of this marker was significantly associated with positivity in vials 1 and 3, but not in vial 2. In 93.3% of the patients, at least one positive marker was observed. Conclusion: The mentioned mRNA could be suggested as sensitive and specific markers in peripheral blood for primary diagnosis of lung cancer.Key Words: Lung neoplasms, RNA, Carcinoembryonic antigen, Sensitivity and specificity 相似文献
109.
Abdol Rasool Jahanbaani Tayebeh Behzad Sedigheh Borhani Mohammad Hossein Karimi Darvanjooghi 《Fibers and Polymers》2016,17(9):1438-1448
In this study, a new approach consisting of chemical treatment steps followed by electrospinning process was applied to produce cellulose nanofibers from wheat straws. Wheat straws were initially pretreated by NaOH solution to open the complex structure of raw materials and remove non-cellulosic materials. Then, acid and alkali hydrolysis was separately performed to eliminate hemicellulose and soluble lignin. Also, bleaching processes were implemented to remove the insoluble lignin. Cellulose nanofibers were produced by electrospinning of various concentrations of cellulose in different solvents including sodium hydroxide/urea/thiourea, pure trifluoroacetic acid (TFA), and TFA/methylene chloride. Images obtained by Scanning Electron Microscope (SEM) showed long and uniform nanofibers produced from electrospinning of cellulose/TFA/methylene chloride solution. An epoxy based laminated composite was prepared by a lamina of cellulose microfiber and electrospun nanofiber mat using hand lay-up composite manufacturing method. The fracture surface of the epoxy nanocomposite was analyzed by SEM images. In addition, the mechanical properties of laminated epoxy composites were compared with pure epoxy by conducting tensile and impact tests. Tensile test results showed that the ultimate tensile strength, elongation, and modulus of laminated epoxy nanocomposites were significantly increased. Moreover, it was found that by adding a nanofiber lamina in the epoxy composite, the impact resistance was significantly improved as a result of crack growth prevention. 相似文献
110.
Effects of dietary essential amino acid deficiencies on the growth performance and humoral immune response in silvery‐black porgy (Sparidentex hasta) juveniles
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Morteza Yaghoubi Mansour Torfi Mozanzadeh Jasem G. Marammazi Omid Safari Enric Gisbert 《Aquaculture Research》2017,48(10):5311-5323
A 6‐week feeding trial was conducted for determining the effects of dietary essential amino acids (EAA) deficiencies on growth performance and non‐specific immune responses in silvery‐black porgy juveniles (4.7 ± 0.1 g initial weight). Eleven isoproteic (ca. 47%) diets were formulated including a control diet containing the optimum quantity of EAA, and ten EAA‐deficient diets. All diets contained 36% fish meal and 18.5% crystalline EAA and non‐essential amino acids (NEAA) as the main source of dietary proteins. All the EAA and NEAA incorporated in the crystalline amino acids mixture of the control diet simulated the amino acids profile of the fish meal. The other 10 EAA‐deficient diets were formulated by the deletion of each of the 10 EAA (crystalline form) from the control diet and replaced by a mixture of NEAA for the adjustment of dietary nitrogen contents. At the end of the experiment, fish fed with threonine‐deficient diet showed the lowest survival rate (p < .05), whereas growth performance decreased in fish fed all EAA‐deficient diets, although the reduction in body growth varied depending on the EAA considered. Plasma total protein decreased in all experimental groups except for fish fed the phenylalanine‐deficient diet. Fish fed with arginine‐ and lysine‐deficient diets had the lowest plasma C3, C4, lysozyme, total immunoglobulin and total superoxide dismutase activity (p < .05). Present results indicated that lysine, methionine and threonine were the most limiting EAA in terms of growth performance; however, arginine, threonine and lysine were the most limiting EAA for innate immunity responses in silvery‐black porgy juveniles. 相似文献