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171.
Shahedur Rahman Hiroshi Takaki Makoto Tamai Yoshitaka Nagatomo 《Soil Science and Plant Nutrition》2013,59(4):881-891
The distribution of zinc, manganese, copper, cobalt, and nickel in Andosols was investigated. Sixty nine soil samples were collected from different horizons of an Andosols profile in Miyakonojo Basin in south Kyushu, Japan, The total contents of heavy metals were determined by digestion and four extraction solutions, 1 M NH4Ac (ammonium acetate) pH 4.5, 0.1 M HCl, 0.01 M EDTA (ethylenediaminetetraacetic acid) pH 6.5, and 0.005 M DTPA (diethylenetri-aminepentaacetic acid) pH 7.3 were used to determine the contents of available Zn, Mn, Cu, Co, and Ni in Andosols in relation to the organic carbon content. The results of the extraction analysis showed that by the use of 0.1 M H Cl high value of extracted heavy metals in the upper layers of the humus horizons were obtained while EDTA extraction yielded a large amount of the above mentioned metals in the high humus horizons. The extractable heavy metals contents were high and these metals closely related to the organic carbon content mostly in the humus horizons in the profile. Where, biocycling process may play an important role in the concentration of heavy metals. Based on the study, it was found that the total content of Zn increased towards the C horizons or pumice layers in the soil profile. Such a trend was also found in the case of the Mn content. While the Cu content in the humus horizons was much higher in the upper part of each humus horizon. According to this study the distribution of heavy metals, Cu (organic matter complexes) in the Andosols profile was more stable than that of Zn (organic matter complexes) in soils. It was shown that Zn in the surface humus horizon was enriched but that some amount was leached under buried conditions. The same phenomenon was also observed in the distribution of Mn in the profile. The movement of Co and Ni in the soil profile was limited, as evidenced by the sharp reduction in the concentrations of these two metals in buried soils. Hence, it is concluded that the distribution of Zn, Mn, Cu, Co, and Ni was considerably higher in the humus horizons of the Andosols profiles. 相似文献
172.
Maize (Zea mays L.) growth and yield are most sensitive to variations in plant density and nitrogen (N) in north-western Pakistan. This study was conducted on the Agricultural Research Farm of NWFP (North West Frontier Province) Agricultural University, Peshawar, from 2002–2004 to establish an accurate plant density and N management system aimed at high yield of maize. The 2 × 3 × 6 factorial experiment was designed having two plant densities (P1 = 60,000 and P2 = 100,000 plants ha?1) and three nitrogen rates (N1 = 60, N2 = 120 and N3 = 180 kg N ha?1) applied to the main plots, while six split application for N in different proportions were applied to subplots at different growth stages of maize in two equal (S1), three equal (S2), three unequal (S3), four equal (S4), five equal (S5) and five unequal splits (S6) at sowing and with 1st, 2nd, 3rd and 4th irrigation at two-week intervals. Growth rate and yield increased with elevated dose and number of N split applications. Improved endurance to high stands allowed maize to intercept and use solar radiation more efficiently, contributing to the remarkable increase in the crop growth rate and yield. 相似文献
173.
M.H. Rahman V. Simonsen 《Acta Agriculturae Scandinavica, Section B - Plant Soil Science》2013,63(1):47-53
Abstract Gene expression was analysed by means of isozyme electrophoresis for three diploid species Brassica rapa (genome AA), B. nigra (BB), and B. oleracea/ B. oleracea var. alboglabra (CC), three amphidiploids B. juncea (AABB), B. napus (AACC) and B. carinata (BBCC), and in 15 interspecific hybrids from crosses within and between the diploids and the amphidiploids. Five enzyme systems were assessed: glucosephosphate isomerase, leucine aminopeptidase, phosphoglucomutase, 6-phosphogluconate dehydrogenase and malate dehydrogenase. Alleles descending from the diploid species were found both in natural and artificially produced amphidiploids. No effect of reciprocal crosses was observed. i.e., the Brassica isozymes were under nuclear gene control. Mendelian segregation in the F2 generation from crossing two resynthesized B. napus was observed for the loci glucosephosphate isomerase-2 and phosphoglucomutase-3. Genome-specific alleles were identified for several loci. No alteration in the allelic expression of isozymes was found when assembling all three Brassica genomes in the trigenomic interspecific hybrids. Moreover, trigenomic hybrids were capable of disclosing a silent allele of leucine aminopeptidase from B. carinata, and thus in this study the capability of isozyme analysis for detecting hidden variation was demonstrated. 相似文献
174.
Ur Rahman Shahid Basit Abdul Ara Neelam Ullah Izhar Rehman Attiq ur 《Gesunde Pflanzen》2021,73(4):541-553
Gesunde Pflanzen - Salinity is a complex abiotic stress that affects physiology and biochemistry of plants and significantly reduces both crop yield and quality. Considering the global... 相似文献
175.
Prevalence and risk factors of subclinical mastitis in lactating dairy cows in north and south regions of Bangladesh 总被引:2,自引:1,他引:1
Swapan Chandra Sarker Mst. Sonia Parvin A. K. M. Anisur Rahman Md. Taohidul Islam 《Tropical animal health and production》2013,45(5):1171-1176
The purpose of the study was to identify the potential risk factors for subclinical mastitis (SCM) in lactating dairy cows in Bangladesh. A cross-sectional study was carried out on randomly selected 212 smallholder dairy farms of Sadar upazilas of Rangpur, Mymensingh, and Satkhira districts of Bangladesh during January to October 2011. The direct interview using a structured questionnaire and physical examination of the cows were done to collect data on 15 variables. Milk samples collected from study cows were subjected to California Mastitis Test (CMT). The diagnosis of SCM was based on the results of CMT and physical examination of udder and milk. The bivariable followed by multivariable analysis was done using SPSS 17.0. Of the total cows examined, 20.2 % had subclinical mastitis. In bivariable analysis, eight risk factors were identified. However, in the final model of multivariable analysis, four potential risk factors were identified. These were history of previous clinical mastitis (odds ratio (OR) 10.51, p?<?0.001), pendulous type of udder (OR 2.26, p?=?0.008), no grass feeding (OR 1.84, p?=?0.039), and body condition score (BCS) 2.5 or less (OR 7.25, p?=?0.054). Four different factors were significantly associated with the occurrence of subclinical mastitis, which need to be considered in the control of the disease. However, particular emphasis should be given on grass feeding and BCS because these traits can be modified or improved to allow prevention of SCM. 相似文献
176.
Muhammad A. Sadiq Abdul-Nasir Tijjani Mohammed S. Auwal Abdul Rahman Mustapha Isa Gulani 《Journal of Equine Veterinary Science》2013
A cross-sectional study of prevalence of antibody against Brucella organisms was conducted among donkeys in three local government areas of Yobe State, northeastern Nigeria. Three hundred adult donkeys of both sexes were sampled, with 100 samples each from local government areas Bursari, Gaidam, and Machina. The overall serological prevalence of brucellosis among donkeys in the three local government areas by both rose bengal plate test (RBPT) and microtiter serum agglutination test (MSAT) was 15 (5.0%), of which five (1.7%) were male and 10 (3.3%) were female donkeys. The overall prevalence by competitive enzyme-linked immunosorbent assay (cELISA) was 10 (3.3%), of which four (1.33%) were male and six (2.0%) were female donkeys. There was a significant association between the female sex of the donkeys and the serological reaction to RBPT, MSAT, and cELISA (P < .05). Of the 100 sera sampled from Bursari, five (5%) were positive by RBPT/MSAT, which comprised two (2%) male and three (3.0%) female donkeys. There was no significant association between the sex of the donkeys and the serological reaction (P > .05). Of the 100 samples from Gaidam, four (4.0%) tested positive by RBPT/MSAT, of which one (1.0%) was male and three (3.0%) were female donkeys (P < .05). Six (6.0%) of the 100 donkey sera samples from Machina tested positive by both RBPT and MSAT, which comprised two (2.0%) male and four (4.0%) female donkeys. There was no significant association between the male sex of the donkeys and the serological reaction (P > .05); however, there was a significant association between the female sex of the donkeys and the serological reaction to both RBPT and MSAT (P < .05). Of the 100 samples from Bursari and the 100 samples from Gaidam, three (3%) from each were positive by cELISA, which comprised one (1%) male and two (2%) female donkeys. There was no statistically significant association between the sex of donkeys and the serological reaction (P > .05). Of the 100 samples tested from Machina, two (2%) male and two (2%) female donkeys were positive for Brucella antibodies by cELISA. No statistically significant association was demonstrated between the sex of the donkeys and the serological reaction to cELISA (P > .05). Because of the importance of donkeys to humans as a source of draft power, infected donkeys could be a source of Brucella infection to humans through close contact, through the respiratory system via contaminated dust or droplets, and through aborted fetuses and discharges from the genitalia. 相似文献
177.
M. M. Rahman R. B. Abdullah W. E. Wan Khadijah 《Journal of animal physiology and animal nutrition》2013,97(4):605-614
Published data on oxalate poisoning in domestic animals are reviewed, with a focus on tolerance and performance. Oxalic acid is one of a number of anti‐nutrients found in forage. It can bind with dietary calcium (Ca) or magnesium (Mg) to form insoluble Ca or Mg oxalate, which then may lead to low serum Ca or Mg levels as well as to renal failure because of precipitation of these salts in the kidneys. Dietary oxalate plays an important role in the formation of Ca oxalate, and a high dietary intake of Ca may decrease oxalate absorption and its subsequent urinary excretion. Oxalate‐rich plants can be supplemented with other plants as forage for domestic animals, which may help to reduce the overall intake of oxalate‐rich plants. Non‐ruminants appear to be more sensitive to oxalate than ruminants because in the latter, rumen bacteria help to degrade oxalate. If ruminants are slowly exposed to a diet high in oxalate, the population of oxalate‐degrading bacteria in the rumen increases sufficiently to prevent oxalate poisoning. However, if large quantities of oxalate‐rich plants are eaten, the rumen is overwhelmed and unable to metabolize the oxalate and oxalate‐poisoning results. Based on published data, we consider that <2.0% soluble oxalate would be an appropriate level to avoid oxalate poisoning in ruminants, although blood Ca level may decrease. In the case of non‐ruminants, <0.5% soluble oxalate may be acceptable. However, these proposed safe levels of soluble oxalate should be regarded as preliminary. Further studies, especially long‐term studies, are needed to validate and improve the recommended safe levels in animals. This review will encourage further research on the relationships between dietary oxalate, other dietary factors and renal failure in domestic animals. 相似文献
178.
179.
Factors Affecting the First Service Conception Rate of Cows in Smallholder Dairy Farms in Bangladesh
MAR Siddiqui ZC Das J Bhattacharjee MM Rahman MM Islam MA Haque JJ Parrish M Shamsuddin 《Reproduction in domestic animals》2013,48(3):500-505
The successful outcome of an insemination is a combination of both male and female fertility‐linked factors. We investigated the first service conception rate of cows at artificial insemination (AI) in the smallholder dairy farms in Bangladesh. Frozen straws were prepared from ejaculates of Bos indicus (n = 7) and Bos indicus × Bos taurus (n = 7) AI bulls. Fertility was determined from 6101 first services in cows that were performed by 18 technicians in four regions between April 2004 and March 2005. Pregnancy was diagnosed by rectal palpation between 60 and 90 days post‐insemination. The Asian version of Artificial Insemination Database Application (AIDA ASIA) was used for bulls‐, cows‐ and AI‐related data recording, and later retrieved for analysis. The mean ± SD number of inseminations performed from individual bulls and their conception rates were 436.0 ± 21.6 and 50.7 ± 1.9%, respectively. Logistic regression demonstrated body condition scores (BCS), heat detection signs, months of AI and their interactions had greatest effects (odds ratios: 1.24–16.65, p < 0.04–0.001) on first service conception rate in cows. Fertility differed (p < 0.02–0.001) between the regions, previous calving months, months of AI, BCS, parity and heat detection signs of cows. Inseminations based on mounting activity (n = 2352), genital discharge (n = 3263) and restlessness and/or other signs (n = 486) yielded a conception rate of 53.6%, 48.8% and 50.1%, respectively (p < 0.05). Conception rate between technicians ranged between 43.4% and 58.6% (p < 0.05). The days interval from calving to first service (overall mean ± SD = 153.4 ± 80.6) had relationship (p < 0.001) with BCS, months of previous calving and parity of the cows. Fertility at AI in smallholder farms can be improved by training farmers on nutrition and reproductive management of the cows. 相似文献
180.
M. R. Ishak Z. Leman S. M. Sapuan M. Z. A. Rahman U. M. K. Anwar 《Fibers and Polymers》2013,14(2):250-257
This study investigated the effects of impregnation modification via vacuum resin impregnation on physical and mechanical properties of sugar palm (Arenga pinnata) fibres. The fibre was evacuated at a constant impregnation pressure of 1000 mmHg impregnation times (0, 5, 10, 15, 20 and 25 min) with two different impregnation agents: phenol formaldehyde (PF) and unsaturated polyester (UP). A notable improvement in the physical properties of sugar palm fibres was observed after they were impregnated with PF and UP for 5 min, shown by the reduction of their moisture content (91 % and 89 %, respectively) and water absorption (43 % and 41 %, respectively) compared to the control sample. However, no significant improvement (p≤0.05) in the physical properties of fibre was observed when the impregnation time was extended (from 10 to 25 min) using both impregnation agents. As for the mechanical properties of the fibre, significant improvement was observed after they were impregnated for 5 min. The fibres impregnated with UP resulted in better fibre toughness and improved mechanical properties as shown in their higher tensile strength and elongation at break compared to the fibres impregnated with PF. Both the physical and mechanical properties showed no significant improvement (p≤0.05) after time for impregnation was extended (from 10 to 25 min) using both impregnation agents. Therefore, it can be concluded that the physical and mechanical properties of sugar palm fibre could be enhanced by impregnating the fibre with thermosetting polymer (PF and UP) for 5 min. It was shown that impregnation with unsaturated polyester (UP) showed better improvement than phenol formaldehyde (PF). In addition, this study also concluded that the unsatisfactory enhancement of the properties of sugar palm fibre even after the impregnation time was extended from 10 to 25 min was due to the use of low impregnation pressure of 1000 mmHg. 相似文献