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141.
Shankar G. Aggarwal Chandra K. Chandrawanshi Raj M. Patel Smita Agarwal Anand Kamavisdar Girdhar L. Mundhara 《Water, air, and soil pollution》2001,130(1-4):855-862
The results of the seasonal analysis of the chemistry of rain, fog and surface water of central India for the two years: June 1996 to May 1998 are presented. A total of 636 rain water samples, 146 fog water samples and 226 surface water samples of 8 locations: namely, Ambikapur, Baikunthpur, Korba, Bilaspur, Raipur, Bhilai, Dallirajhara and Kanker, from different sites were collected for the present study. This paper documents the occurrence of acidic rain and fog events and their effect on surface water pH and aquatic life in central India. Most of the rain and fog water samples collected from Baikunthpur and Korba sites were found to be acidic in nature (i.e. pH < 5). The volume weighted mean pH of rain and fog water samples of these sites was 4.8 and 4.4 with lowest pH 4.4 and 4.0, respectively. However, samples from Ambikapur, Bilaspur, Raipur and Bhilai were slightly acidic and their pH values were always around 5.8. One reservoir (mean pH 5.8) and two stop dams (mean pH 4.4 and 4.2) in Baikunthpur area were found to be acidic. The effect of acidification of water on metal-accumulation in muscles of fishes was studied. Concentrations of Al, Hg, Mn, Cd and Pb were higher in fish from acid, than from less acid waters. Causes of acidification of the atmospheric water and surface water are critically discussed. 相似文献
142.
Copper and Cd accumulation was determined in Bacopa monnieri, a common aquatic plant. Plants showed a capability to accumulate both metals in single and mixed metal treatments. Copper accumulation was stimulated by the presence of Cd whereas uptake of Cd was inhibited by Cu. The plants showed high concentration factors for both metals. The results suggest the possibility of using this plant for mitigating Cu and Cd pollution in the aquatic environment. 相似文献
143.
Denitrification and nitrous oxide to nitrous oxide plus dinitrogen ratios in the soil profile under three tillage systems 总被引:1,自引:0,他引:1
Abdirashid?A.?ElmiEmail author Chandra?Madramootoo Chantal?Hamel Aiguo?Liu 《Biology and Fertility of Soils》2003,38(6):340-348
There is a growing interest in the adoption of conservation tillage systems [no-till (NT) and reduced tillage (RT)] as alternatives to conventional tillage (CT) systems. A 2-year study was conducted to investigate possible environmental consequences of three tillage systems on a 2.4-ha field located at Macdonald Research Farm, McGill University, Montreal. The soil was a sandy loam (0.5 m depth) underlain by a clay layer. Treatments consisted of a factorial combination of CT, RT, and NT with the presence or absence of crop residue. Soil NO3--N concentrations tended to be lower in RT than NT and CT tillage treatments. Denitrification and N2O emissions were similar among tillage systems. Contrary to the popular assumption that denitrification is limited to the uppermost soil layer (0–0.15 m), large rates of N2O production were measured in the subsurface (0.15–0.45 m) soil, suggesting that a significant portion of produced N2O may be missed if only soil surface gas flux measurements are made. The N2O mole fraction (N2O:N2O+N2) was higher in the drier season of 1999 under CT than in 2000, with the ratio occasionally exceeding 1.0 in some soil layers. Dissolved organic C concentrations remained high in all soil depths sampled, but were not affected by tillage system. 相似文献
144.
The protective role of 18 amino acids on the acute toxicity of Cu in a fresh water cladoceran, Daphnia magna is reported. One hundred percent mortality in 48 hr of exposure occured at 0.56 mg L?1 of Cu or higher. A dose of each tested amino acid (10 mg L?1 was found to significantly neutralize the toxic effect of Cu as evidenced by a decrease in mortality and a significant increase in the median survival time (LT50) value). The 48 hr LC50 value was 0.093 mg L?1 for Cu alone, while the LC50s with Cu plus amino acids ranged from 0.438 to 2.516 mg L?1 of Cu, suggesting a 4.7 to 27 fold decrease in acute toxicity of Cu. A significant difference between LC50 of Cu alone and Cu with amino acids was observed. The role of amino acids for protection against heavy metal pollution stress in aquatic animals is discussed. 相似文献
145.
Genetic variability of drought-avoidance root traits in the mini-core germplasm collection of chickpea (Cicer arietinum L.). 总被引:2,自引:0,他引:2
Junichi?KashiwagiEmail author L.?Krishnamurthy Hari?D.?Upadhyaya Hari?Krishna S.?Chandra Vincent?Vadez Rachid?Serraj 《Euphytica》2005,146(3):213-222
Extensive and deep root systems have been recognized as one of the most important traits for improving chickpea (Cicer arietinum L.) productivity under progressively receding soil moisture conditions. However, available information on the range of variation
for root traits is still limited. Genetic variability for the root traits was investigated using a cylinder culture system
during two consecutive growth seasons in the mini-core germplasm collection of ICRISAT plus several wild relatives of chickpea.
The largest genetic variability was observed at 35 days after sowing for root length density (RLD) (heritability, h
2 = 0.51 and 0.54) across seasons, and followed by the ratio of plant dry weight to root length density with h
2 of 0.37 and 0.50 for first and second season, respectively. The root growth of chickpea wild relatives was relatively poor
compared to C. arietinum, except in case of C. reticulatum. An outstanding genotype, ICC 8261, which had the largest RLD and one of the deepest root system, was identified in chickpea
mini-core germplasm collection. The accession ICC 4958 which was previously characterized as a source for drought avoidance
in chickpea was confirmed as one with the most prolific and deep root system, although many superior accessions were also
identified. The chickpea landraces collected from the Mediterranean and the west Asian region showed a significantly larger
RLD than those from the south Asian region. In addition, the landraces originating from central Asia (former Soviet Union),
characterized by arid agro-climatic conditions, also showed relatively larger RLD. As these regions are under-represented
in the chickpea collection, they might be interesting areas for further germplasm exploration to identify new landraces with
large RLD. The information on the genetic variability of chickpea root traits provides valuable baseline knowledge for further
progress on the selection and breeding for drought avoidance root traits in chickpea. 相似文献
146.
Mahboob A. Chowdhury Chandra P. Andrahennadi Alfred E. Slinkard Albert Vandenberg 《Euphytica》2001,118(3):331-337
Resistance to ascochyta blight of lentil (Lens culinaris Medikus),caused by the fungus Ascochyta lentis, is determined by a single recessive gene, ral
2, in the lentil cultivar Indian head. Sixty F2 individuals from a cross between Eston (susceptible) and Indian head (resistant) lentil were analyzed for the presence of
random amplified polymorphic DNA (RAPD) markers linked to the ral
2gene, using bulked segregant analysis (BSA). Out of 800 decanucleotide primers screened, two produced polymorphic markers
that co-segregated with the resistance locus. These two RAPD markers, UBC2271290and OPD-10870, flanked and were linked in repulsion phase to the gene ral
2 at 12 cm and 16 cm, respectively. The RAPD fragments were converted to SCAR markers. The SCAR marker developed from UBC2271290 could not detect any polymorphism between the two parents or in the F2. The SCAR marker developed from OPD-10870 retained its polymorphism. The polymorphic RAPD marker UBC2271290 and the SCAR marker developed from OPD-10870 can be used together in a marker assisted selection program for ascochyta blight resistance in lentil.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
147.
Ahmad Sheikh Firdous Gaur Gyanendra Kumar Sahoo Nihar Ranjan Bharti P. K. Naha Binoy Chandra 《Tropical animal health and production》2020,52(1):109-114
Tropical Animal Health and Production - Variances and genetic parameters (heritability and correlation) were estimated for pre-weaning weights from birth to 6 weeks of age at weekly... 相似文献
148.
149.
Ripon Chandra Paul Trung Ba Nguyen Yu Okuda Thu Nu Anh Le Jovilisi Mosese Dau Tabuyaqona Yuri Konishi Yoshi Kawamoto Ken Nozawa Tetsuo Kunieda 《Animal Science Journal》2020,91(1)
There are currently eight native horse populations in Japan, namely, Hokkaido, Kiso, Noma, Taishu, Misaki, Tokara, Miyako, and Yonaguni horses. Since locomotion traits, including gaitedness, are important for riding and packing horses, the genetic properties associated with these traits could be informative for understanding the characteristics and history of these horses. In this study, we investigated the distribution of the mutant allele of DMRT3 gene (DMRT3:p.Ser301Ter) associated with ambling gaits in the Japanese native horse. We also examined haplotypes of SNPs in the 83‐kb region including DMRT3 gene by genotyping four SNPs in this region. The results revealed the presence of DMRT3:p.Ser301Ter in the Hokkaido and Yonaguni populations at allele frequencies of 0.18 and 0.02, respectively, and the observed haplotype associated with DMRT3:p.Ser301Ter was estimated as the most common haplotype in the horses in the world. Since DMRT3:p.Ser301Ter has been hypothesized to spread across Eurasian continent from Medieval England after 850 to 900 CE, our findings of the presence of DMRT3:p.Ser301Ter with the common haplotype in the Japanese native horses will provide a new insight into the history of the Japanese native horse, such as considerable level of gene flow from Eurasian continent after 850 to 900 CE. 相似文献
150.
Seed morphometric characters and oil content were studied in multiple-use plant, Calophyllum inophyllum L. of two countries, Australia (southern hemisphere) and Sri Lanka (northern hemisphere). Seven provenances were selected
which included three from northern Australia and four from Sri Lanka. Twelve Candidate plus trees (CPTs) each were selected
from 2 to 3 different locations within each provenance based on the morphometric and qualitative traits (GBH > 100 cm). Seed
collection in both hemispheres was carried out from May to August 2008. Calophyllum inophyllum L. provenances showed a distinct hemisphere variation in their seed-related characters and oil content. All provenances differed
significantly (P < 0.05) with one another in seed length. Seeds from Anuradhapura, Sri Lanka and seeds from Cardwell Australia recorded the
highest (≈57%) and the lowest oil (≈31%) content respectively. Strong correlations were found between seed morphometric characters.
Relatively weaker correlations were found between seed morphometric characters and oil content. Variations in seed-related
characters were largely attributed by the provenance contribution which shows the significance of the effect of genetic variability
on above mentioned seed related characters. 相似文献