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61.
Although application of salicylic acid (SA) to various plants grown on saline soils has been examined adequately, the effect of SA on changes during grain filling period has not been studied in details. In this 2-year field study, the grain-filling pattern of barley has been monitored as affected by different SA concentrations (0, 0.5, 1.0, 1.5, and 2.0?mM) under varied irrigation salinity levels (2 and 12?dSm?1) during 2012–2013 and 2013–2014 growing seasons. In both years, total soluble carbohydrates (TSC) increased up to 15?days after anthesis (DAA) and then decreased until the end of the grain-filling period. However, starch content (SC) and the mean grain weight (MGW) increased form the first sampling, and such increase was substantial between 15 and 25 DAA. The grain growth rate (GGR) and the absolute grain growth rate (AGGR) were enhanced up to 20 DAA and then were reduced until 30 DAA. The grain-filling pattern changed by salt stress, so that TSC was greater for the salt stressed plants from 15 or 10 DAA in the first and the second years, respectively. Throughout the grain-filling period, SC, MGW, and AGGR were lower under saline conditions in both years. Application of SA increased TSC, SC, MGW, GGR, and AGGR from 15 to 20 DAA, however, the effect of SA was obvious earlier under saline than the non-saline conditions. Generally, it can be concluded that SA foliar application might increase grain weight through modulating the negative impact of salt stress on carbohydrate and starch contents. It also appeared that the effect of SA was obvious earlier under salt stress conditions.  相似文献   
62.
In the current paper, we fabricated, characterized, and applied nanocomposite hydrogel based on alginate (Alg) and nano-hydroxyapatite (nHA) loaded with phenolic purified extracts from the aerial part of Linum usitatissimum (LOH) as the bone tissue engineering scaffold. nHA was synthesized based on the wet chemical technique/precipitation reaction and incorporated into Alg hydrogel as the filler via physical cross-linking. The characterizations (SEM, DLS, and Zeta potential) revealed that the synthesized nHA possess a plate-like shape with nanometric dimensions. The fabricated nanocomposite has a porous architecture with interconnected pores. The average pore size was in the range of 100–200 µm and the porosity range of 80–90%. The LOH release measurement showed that about 90% of the loaded drug was released within 12 h followed by a sustained release over 48 h. The in vitro assessments showed that the nanocomposite possesses significant antioxidant activity promoting bone regeneration. The hemolysis induction measurement showed that the nanocomposites were hemocompatible with negligible hemolysis induction. The cell viability/proliferation confirmed the biocompatibility of the nanocomposites, which induced proliferative effects in a dose-dependent manner. This study revealed the fabricated nanocomposites are bioactive and osteoactive applicable for bone tissue engineering applications.  相似文献   
63.
Pharmacokinetics of streptomycin in camels   总被引:1,自引:0,他引:1  
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64.
Growth, meat quality, and carcass traits are of economic importance in swine breeding. Understanding their genetic basis in purebred (PB) and commercial crossbred (CB) pigs is necessary for a successful breeding program because, although the breeding goal is to improve CB performance, phenotype collection and selection are usually carried out in PB populations housed in biosecure nucleus herds. Thus, the selection is indirect, and the accuracy of selection depends on the genetic correlation between PB and CB performance (rpc). The objectives of this study were to 1) estimate genetic parameters for growth, meat quality, and carcass traits in a PB sire line and related commercial CB pigs and 2) estimate the corresponding genetic correlations between purebred and crossbred performance (rpc). Both objectives were investigated by using pedigree information only (PBLUP) and by combining pedigree and genomic information in a single-step genomic BLUP (ssGBLUP) procedure. Growth rate showed moderate estimates of heritability for both PB and CB based on PBLUP, while estimates were higher in CB based on ssGBLUP. Heritability estimates for meat quality traits were diverse and slightly different based on PB and CB data with both methods. Carcass traits had higher heritability estimates based on PB compared with CB data based on PBLUP and slightly higher estimates for CB data based on ssGBLUP. A wide range of estimates of genetic correlations were obtained among traits within the PB and CB data. In the PB population, estimates of heritabilities and genetic correlations were similar based on PBLUP and ssGBLUP for all traits, while based on the CB data, ssGBLUP resulted in different estimates of genetic parameters with lower SEs. With some exceptions, estimates of rpc were moderate to high. The SE on the rpc estimates was generally large when based on PBLUP due to limited sample size, especially for CBs. In contrast, estimates of rpc based on ssGBLUP were not only more precise but also more consistent among pairs of traits, considering their genetic correlations within the PB and CB data. The wide range of estimates of rpc (less than 0.70 for 7 out of 13 traits) indicates that the use of CB phenotypes recorded on commercial farms, along with genomic information, for selection in the PB population has potential to increase the genetic progress of CB performance.  相似文献   
65.
Limited information is available on the effect of preceding crop on phytoavailability of zinc (Zn) in soil. This pot experiment examined the effect of four preceding crops including clover, sunflower, safflower, and sorghum residues on shoot and grain Zn uptake by two wheat genotypes differing in Zn-deficiency tolerance Back Cross and Kavir in a calcareous Zn-deficient soil. Incorporation of all preceding crop residues into the soil significantly increased organic matter (OM) content, dissolved organic C (DOC), and diethylene triamine pentaacetic acid (DTPA) extractable Zn concentration in the soil. Residues of safflower and clover had the greatest effect on increasing DOC. Shoot and grain Zn concentrations were increased by incorporating all pre-crop residues into the soil although this increase was greater at safflower and clover treatments. Incorporation of sorghum residues into the soil had a negative effect on shoot and grain dry matter yield of wheat. Incorporation of safflower and clover residues into the soil increased Zn uptake by wheat shoot and grain. There was a positive significant correlation between shoot and grain Zn concentration with DOC in soil solution. It shows that DOC, produced from decomposition of crop residues, has facilitated Zn uptake by roots of wheat plants and particularly its transfer to grains.  相似文献   
66.
Highly pathogenic avian influenza (HPAI) H5N1 virus is causing the death of a large number of wild birds and poultry. HPAI H5N1 was reported in the north of Iran in 2011. In this study, two A/Chicken/Iran/271/2011 and A/Duck/Iran/178/2011 viruses were genetically characterized by sequence analysis of Hemagglutinin (HA) and Neuraminidase (NA) genes. Phylogenetic analysis revealed that these viruses were different from previous Iranian isolates (Clade 2.2) and belonged to the subclade 2.3.2.1. The results showed that the detected viruses are almost identical to each other and closely related to HPAI H5N1 strains isolated in Mongolia in 2010. Based on the amino acid sequence analysis, these viruses at their HA cleavage sites contained the multibasic amino acid motif PQRERRRK-R/GLF lacking a lysine residue compared with the previous reports of the same motif. There is also a 20-amino acid deletion (resides 49–69) in the NA stalk similar to other viruses isolated after 2000. It seems that introduction of HPAI H5N1 to Iran might have happened by wild birds from Mongolian origin virus.  相似文献   
67.
This study was undertaken to study the effect of Satureja khuzestanica essential oil (SKEO) in male rat fertility. SKEO was administered orally at doses of 75, 150, and 225 mg/kg/day for 45 days through drinking water. Treated and control rats were mated with female on day 45 of treatment. SKEO significantly improved all the parameters evaluated such as potency, fecundity, fertility index, and litter size. Moreover, concentrations of FSH and testosterone were significantly increased in SKEO-treated groups. Also the weights of testes, seminal vesicles, and ventral prostate weights were increased by SKEO (225 mg/kg). Histopathological analysis showed that in male rats treated with SKEO (150, 225 mg/kg) the number of spermatogonium, spermatid cords, Leydig cells, and spermatozoids was increased. Also in these groups, the Sertoli cells were hypertrophic.  相似文献   
68.
Chitin was prepared from Persian Gulf shrimp (Metapenaeus monoceros), and then, the obtained chitin was hydrolyzed by hydrochloric acid solutions. The production yield of glucosamine hydrochloride from chitin was optimized, and the effect of three factors (acid concentration, acid to chitin ratio, and reaction time) was investigated. A Box-Behnken design by Minitab software created 12 reactions with different conditions. Each reaction was performed in two replicates. Response surface methodology was used for predicting the glucosamine preparation. The optimum conditions for glucosamine hydrochloride preparation were 30 and 37% hydrochloric acid, 9:1 (v/w) acid solution to solid ratio, and 4 h of reaction time. Time ratio and time acid concentrations were the effective factors on the yield.  相似文献   
69.
Abstract: As the largest archipelagic nation in the world, with distinctive environmental conditions and biodiversity, Indonesia on the one hand has tremendous natural and environmental riches while on the other hand faces a variety of environmental problems. After three decades of the New Order era, 1967–1998, Indonesian society is in a crucial transformation process towards a more democratic era. At the same time, as indicated in that country's decentralisation laws No. 22/99 and 25/99, Indonesia is also shifting its style of government, from a centralistic to decentralised one. These two trends are happening simultaneously with globalisation prompting a flow of global capital that directly increases pressure on the Indonesian environment. This paper evaluates the decentralisation of environmental management programmes in Indonesia and focuses on the implications of these changes. The weaknesses of current environmental policies and programmes in Indonesia, which give too dominant a role to the government and neglect civil society's involvement in natural resources and environmental management, are analysed. Further, the paper addresses the lack of attention to date to issues of environmental rights and justice that create many complex environmental and social conflicts throughout Indonesia. We conclude by recommending some fundamental changes to environmental policies and programmes in the decentralised system.  相似文献   
70.
Seven pot experiments were conducted to study the direct and the accumulative effect of urea containing (0.4, 1.0, 1.5, 2.0, 3.0 and 4.0 %) biuret on the growth of rice, wheat, and maize plants and their N content and N uptake in two fine textured alluvial soils and one sandy clay loam (highly calcareous) soil. It was found that both rice and wheat grain yields were not significantly reduced in all soils where urea containing high percentage of biuret was used namely 3 % and 4 %. Ammonium sulphate fertilizer was superior to urea in plant production only in the sandy clay loam. Moreover, the N recovery was higher in the alluvial soils in comparison to the sandy clay loam. The accumulative addition of biuret to the soils did not further reduce either the growth rate or the N uptake of the plants.  相似文献   
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