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451.
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453.
Shahbudin Saad Mohd. Lokman Husain Rosnan Yaacob Toshiyuki Asano 《Mangroves and Salt Marshes》1999,3(1):51-58
This paper reports on a study of accretion rate and sedimentological variability in a estuarine mangrove swamp. One hundred and sixteen stations were monitored for 2 years. In addition, surface sediment samples were collected at 52 stations during the months of May, June and July (1994) to represent the nonmonsoon sediments and November, December (1994) and January (1995) to represent the monsoon sediments. Results show that the accretion rate for the first year was 1.46±0.13cm/yr and 0.66±0.04cm/yr for the second year thus making the average accretion for the 2 years period to be 1.06cm/yr. The average accretion rate for the monsoon season (0.26 ± 0.04cm/month) was found to be significantly higher than the nonmonsoon season (0.12 ± 0.03cm/month). Nevertheless, the same is not true for the surface sediment characteristics. The sedimentological characteristics between the monsoon and the nonmonsoon sediments were not significantly different. 相似文献
454.
Samanthi Priyanka Withanage Md Aktar Hossain Sures Kumar M. Hairul Azman B Roslan Mohammad Puad Abdullah Suhaimi B. Napis Nor Aini Ab. Shukor 《Breeding Science》2015,65(3):177-191
Kenaf (Hibiscus cannabinus L.; Family: Malvaceae), is multipurpose crop, one of the potential alternatives of natural fiber for biocomposite materials. Longer fiber and higher cellulose contents are required for good quality biocomposite materials. However, average length of kenaf fiber (2.6 mm in bast and 1.28 mm in whole plant) is below the critical length (4 mm) for biocomposite production. Present study describes whether fiber length and cellulose content of kenaf plants could be enhanced by increasing GA biosynthesis in plants by overexpressing Arabidopsis thaliana Gibberellic Acid 20 oxidase (AtGA20ox) gene. AtGA20ox gene with intron was overexpressed in kenaf plants under the control of double CaMV 35S promoter, followed by in planta transformation into V36 and G4 varieties of kenaf. The lines with higher levels of bioactive GA (0.3–1.52 ng g−1 fresh weight) were further characterized for their morphological and biochemical traits including vegetative and reproductive growth, fiber dimension and chemical composition. Positive impact of increased gibberellins on biochemical composition, fiber dimension and their derivative values were demonstrated in some lines of transgenic kenaf including increased cellulose content (91%), fiber length and quality but it still requires further study to confirm the critical level of this particular bioactive GA in transgenic plants. 相似文献
455.
Hilal Ozkilinc Omer Frenkel Dani Shtienberg Shahal Abbo Amir Sherman Abdullah Kahraman Canan Can 《European journal of plant pathology / European Foundation for Plant Pathology》2011,131(3):529-537
Ascochyta blight, caused by Didymella rabiei, affects both domesticated chickpea and its congeneric wild relatives. The aim of this study was to compare the aggressiveness
of D. rabiei isolates from wild and domesticated Cicer spp. in Turkey and Israel on wild and domesticated hosts from both countries. A total of eight isolates of D. rabiei sampled from C. pinnatifidum, C. judaicum and C. arietinum in Turkey and Israel was tested on two domesticated chickpea cultivars and two wild Cicer accessions from Turkey and Israel. Using cross-inoculation experiments, we compared pathogen aggressiveness across the different
pathogen and host origin combinations. Two measures of aggressiveness were used, incubation period and relative area under
the disease progress curve. The eight tested isolates infected all of the host plants, but were more aggressive on their original
hosts with one exception; Turkish domesticated isolates were less aggressive on their domesticated host in comparison to the
aggressiveness of Israeli domesticated isolates on Turkish domesticated chickpea. C. judaicum plants were highly resistant against all of the isolates from different origins except for their own isolates. Regardless
of the country of origin, the wild isolates were highly aggressive on domesticated chickpea while the domesticated isolates
were less aggressive on the wild hosts compared with the wild isolates. These results suggest that the aggressiveness pattern
of D. rabiei on different hosts could have been shaped by adaptation to the distinct ecological niches of wild vs. domesticated chickpea. 相似文献
456.
Mohd Yasin Ina-Salwany Mohd Yusoff Sabri Mohd Zamri-Saad Abd Wahid Mohd Effendy 《Tropical animal health and production》2011,43(1):179-187
This study was carried out to determine the antibody responses and protective capacity of an inactivated recombinant vaccine
expressing the fimbrial protein of Pasteurella multocida B:2 following intranasal vaccination against hemorrhagic septicemia in goats. Goats were vaccinated intranasal with 106 CFU/mL of the recombinant vaccine (vaccinated group) and 106 CFU/mL of pET32/LIC vector without fimbrial protein (control group). All three groups were kept separated before all goats
in the three groups were challenged with 109 CFU/mL of live pathogenic P. multocida B:2. During the course of study, both serum and lung lavage fluid were collected to evaluate the antibody levels via enzyme-linked
immunosorbent assay. It was found that goats immunized with the inactivated recombinant vaccine developed a strong and significantly
(p < 0.05) higher specific IgA and IgG responses in both serum and lung lavage fluid samples compared to the control and unvaccinated
groups. Following intratracheal challenge, the rate of isolation was 17% for the vaccinated group, 67% for the control group
and 100% for the unvaccinated group. However, none of the goat from the vaccinated group had P. multocida B:2 in the liver, tonsil and heart. Therefore, the study revealed that an inactivated recombinant vaccine significantly provides
significant protection against high dose challenge and enhances the stimulation of the local and systemic immunities. 相似文献
457.
Water harvesting is viable alternatives for rainfed agricultural production in semiarid lands. A field experiment was conducted to evaluate the efficiency of a relatively new water harvesting technique, called sand ditch, for moisture and soil conservation. Twelve field plots of 10 m × 2 m were constructed in two adjacent fields having silt loam soils but varied in soil depth, 0.75 m and 2 m, and slope of 10% and 12%. A 130 L barrel was installed at the downslope end of the plots to collect water and sediments at the end of each rainstorm along the rainy season. Three types of treatments were used in duplicates (12 plots in total); sand-ditch plots in which a ditch of 2-m long, 1 m wide and 0.8 m deep was constructed in the middle of plots across the slope (2 in each field), two compacted plots and two plots covered with plastic mulch in addition to four control plots, 2 in each field. The total amount of runoff, sediment concentration, total infiltration and sediment loss for the experimental plots were measured or calculated after each storm during the winter season 2004/2005. Experimental results showed that sand-ditch technique significantly reduced runoff and sediment loss and increased infiltration and soil moisture compared to control or compacted plots. The overall average runoff and sediment reductions in the sand-ditch plots were 46% and 61% compared to control plots. Sediment losses from compacted plots were about 2.2 and 6 folds higher than control and sand-ditch plots, respectively making soil compaction unsuitable technique for rainfall harvesting under the current experimental and climatic conditions. Construction of sand ditch also increased the dry matter yield of native grass by an average of 62% and 40% in the two experimental fields compared to control. 相似文献
458.
459.
K. Heinoun E. Muhammad H. Abdullah Smadi D. Annahhas R. Abou Kubaa 《EPPO Bulletin》2021,51(1):213-215
The fall armyworm Spodoptera frugiperda is a lepidopteran pest that can damage and destroy a wide variety of crops. It is widely present in the Americans and has been invasive in Africa since 2016. Larvae of S. frugiperda were found for the first time in four rural farms on maize plants (Zea mays) located in Tafas town (Dara’a Governorate, in the south‐west of Syria) in November 2020. Infested maize showed the typical damage symptoms caused by S. frugiperda. Furthermore, morphological identification of larvae based on standard parameters of larvae confirmed the identity of the pest as fall armyworm. Considering the recent introduction of the pest into the EPPO region, it could be concluded that the pest probably entered Syria through natural spread (active flight and via wind currents) from Jordan, which borders Syria in the southern part and where the pest was found very recently. 相似文献
460.
Abidalrazzaq Musluh Al Rubaye Omar Yetisir Halit Ulas Firdes Ulas Abdullah 《Gesunde Pflanzen》2021,73(3):375-389
Gesunde Pflanzen - In this study, pepper (Capsicum annuum L.) inbred lines were grafted onto different rootstock genotypes and tested under saline conditions. A hydroponic... 相似文献