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101.
Samiran Bandyopadhyay Goutam Mandal Piu Saha Mihir Sarkar 《Research in veterinary science》2009,87(1):85-90
In Arunachal Pradesh and other sub-Himalayan areas of India, accidental consumption of Senecio plants by yaks is often fatal as the plant contains toxic alkaloids like Seneciophylline. The present investigation was undertaken to demonstrate the pro-oxidant effects of an ethanolic extract of Seneciochrysanthemoides (S-EtOH). S-EtOH impaired viability in macrophages, the IC50 being 13.8 ± 1.11 μg/mL. The effect of S-EtOH (1 μg/mL) on generation of reactive oxygen species (ROS) in macrophages was measured by flow cytometry using 2′,7′-dichlorofluorescein diacetate (H2DCFDA) where it caused a significant increase in the mean fluorescence channel (MFC) from 8.55 ± 0.03 to 47.32 ± 2.25 (p < 0.001). S-EtOH also effected a 3.8-fold increase in extracellular nitric oxide (NO) generation from 4.90 ± 0.72 μM to 18.79 ± 0.32 μM (p < 0.001), a 2.2-fold increase in intracellular NO production, the MFC increasing from 14.95 ± 0.48 to 33.34 ± 1.66 (p < 0.001), and concomitantly depleted non protein thiols as analyzed by flow cytometry using mercury orange, with a reduction in MFC from 632.5 ± 49.44 to 407.4 ± 12.61 (p < 0.01). Additionally, S-EtOH (14 μg/mL, 24 h) caused apoptosis as evident by increased Annexin V binding and terminal deoxynucleotidyl transferase mediated dUTP DNA nick end labeling. Taken together, the cytotoxicity of S-EtOH can be partly attributed to its capacity to inflict oxidative damage via generation of both reactive oxygen and nitrogen species culminating in apoptosis. 相似文献
102.
Kamlesh K. Meena Sukumar Mesapogu Manish Kumar Mahesh S. Yandigeri Geeta Singh Anil K. Saxena 《Biology and Fertility of Soils》2010,46(2):169-174
In this study, inoculation of the chickpea (Cicer arietinum) with the novel symbiotic fungus (Piriformospora indica) was analysed in combination with the Tn5-lacZ-tagged phosphate-solubilising bacterium Pseudomonas striata. This study aims to evaluate whether the co-inoculation of these two species would enhance the population buildup of P. striata in the rhizosphere, P uptake, growth and yield of chickpea. Single inoculation of P. indica and P. striata has a negative effect on plant growth and yield of chickpea. Data showed that the combination of the two microorganisms had
a synergistic effect on population buildup of P. striata and plant dry biomass with respect to their single inoculation. However, the P uptake was not significantly influenced by
single or combined inoculation of two species. At 20 days after sowing, the influence of combined inoculation on the population
of P. striata was positive; at 60 days after sowing, it was neutral as the populations in treatments with single and combined inoculation
were at par; and at harvest, it was negative The population of P. striata was higher at flowering stage as compared to 20 days after sowing and at harvest. 相似文献
103.
Naqvi SM Joshi A Gulyani R Kumar D Kolte AP Kumar S Maurya VP Saha S Mittal JP Singh VK 《The Veterinary record》2006,159(16):522-526
The Garole is a prolific breed of microsheep that possesses the FecB gene, which increases ovulation rate. The purpose of this study was to compare embryo production by multiple ovulation in seven Garole ewes with that in seven normal size, non-prolific Malpura ewes, and assess the influence of the large body size of Awassi crossbred recipient ewes on the birth-weight of Garole lambs. Oestrus was synchronised with two intramuscular injections of 7.5 mg prostaglandin F(2alpha) administered 10 days apart. The donor ewes were superovulated by the use of pregnant mare serum gonadotrophin and follicle-stimulating hormone. The onset and duration of oestrus were similar in both breeds. The Garole donors had higher total mean (se) ovarian responses (15.6 [3.6] v 9.1 [2.3]), ovulation rate (13.6 [3.1] v 8.4 [2.2]) and produced more transferable embryos (6.0 [3.5] v 4.0 [0.9]) than the Malpura donors, but the differences were not statistically significant. The Garole lambs produced by embryo transfer were on average 57.8 per cent heavier at birth than contemporary Garole lambs produced by natural mating. 相似文献
104.
Patnaik Siddhi Sahoo Lakshman Mohanty Mausumee Bit Amrita Meher Prem Kumar Das Sachidananda Jayasankar Pallipuram Saha Jatindra Nath Das Paramananda 《Fish physiology and biochemistry》2021,47(5):1353-1367
Fish Physiology and Biochemistry - Activin receptor type IIB (ActRIIB) is a transmembrane serine/threonine kinase receptor which plays a pivotal role in regulating the reproduction in vertebrates... 相似文献
105.
Microsatellite markers associated with lint percentage trait in cotton, Gossypium hirsutum 总被引:2,自引:0,他引:2
I. Y. Abdurakhmonov Z. T. Buriev S. Saha A. E. Pepper J. A. Musaev A. Almatov S. E. Shermatov F. N. Kushanov G. T. Mavlonov U. K. Reddy J. Z. Yu J. N. Jenkins R. J. Kohel A. Abdukarimov 《Euphytica》2007,156(1-2):141-156
Molecular markers associated with fiber development traits have the potential to play a key role in understanding of cotton
fiber development. Seventeen SSRs out of 304 markers tested from MGHES (EST-SSR), JESPR (genomic SSR), and TMB (BAC-derived
SSR) collections showed significant linkage associations (using a Kurskal-Wallis non-parametric test) with lint percentage
QTL in a set of recombinant inbred cotton lines (RILs) segregating for lint percentage. The permutation test of these potential
markers associated with lint percentage QTL(s) determined that 12 SSR markers have stable estimates, exceeding empirically
chosen threshold significance values at or above α = 0.01. Interval mapping demonstrated that 9 SSRs with stable critical
LOD threshold values at α = 0.01 have significant QTL effect. Multiple QTL-mapping (MQM) revealed that at least, two highly
significant fiber development QTLs exist around regions TMB0471 and MGHES–31 (explained about 23–59% of the phenotypic variation
of lint percentage) and around markers MGHES–31 and TMB0366 (accounted for 5.4–12.5% phenotypic variation of lint percentage).
These markers, in particular fiber-specific EST-SSRs, might be the possible ‘candidate’ loci contributing for fiber development
in cotton. BAC-derived SSRs associated with fiber trait are the possible markers that are useful for the identification of
physical genomic contigs that contain fiber development genes. Several lint percentage trait associated SSR markers have been
located to chromosomes 12, 18, 23, and 26 using deletion analysis in aneuploid chromosome substitution lines. Outcomes of
the work may prove useful in understanding and revealing the molecular basis of the fiber development, and the utilization
of these markers for development of superior cotton cultivars through marker-assisted selection (MAS) programs.
I. Y. Abdurakhmonov and S. Saha contributed equally to the work 相似文献
106.
A laboratory experiment was conducted to study the stability of sulfosulfuron [1-(2-ethylsulfonylimidazo[1,2-a]pyridin-3-ylsulfonyl)-3-(4,6-dimethoxypyrimidin-2yl) urea] in a controlled environment of pH, temperature, solvent, and surface. In another experiment the photostability of sulfosulfuron was studied after irradiation under sunlight. Under alkaline condition, it yielded 1-(2-ethylsulfonylimidazo[1,2-a]pyridin-3-yl-3-(4,6-dimethoxypyrimidin-2-yl) amine, and under acidic condition it degraded to 1-(2-ethylsulfonylimidazo[1,2-a] pyridin)-3-sulfonamide and 4,6-dimethoxy-2-aminopyrimidine. Photodegradation included breaking of a sulfonylurea bridge, as in the case of acidic hydrolysis and contraction of the sulfonylurea bridge was the major pathway of alkaline hydrolysis. 相似文献
107.
Summary A greenhouse experiment was conducted with wetland rice (Oryza sativa cv. IR-50) in a clay-loam soil (Fluventic Eutrochrept) to study the effect of cyanobacterial inoculation a mixed culture of Aulosira fertilissima, Nostoc muscorum, Nostoc spp., and Anabaena spp., applied at the rate of 0.15 g (dry weight pot-1 or 43 kg ha-1) on acetylene reduction activity in soil and the root system (excised root), and the grain and straw yield. The effects of applying P (40 kg ha-1), N (60 kg ha-1), and P+N to the soil were also evaluated. Cyanbacterial inoculation significantly increased (more than 200% on average) photo-dependent acetylene reduction activity in soils, particularly where the indigenous activity was considerably low, i.e. under unfertilized and N-fertilized conditions. The effect of inoculation was prominent at the maximum tillering and grain formation stages of the crop. This inoculation benefit was, however, marginal in P-applied soils (P and P+N), where the indigenous activity was stimulated more than threefold. The inoculation led to a remarkable increase in root-associative acetylene reduction activity after the maximum tillering stage of the crop, particularly with applied N but for other treatments this inoculation effect was not significant. Cyanobacterial inoculation also increased the grain and straw yield of the crop when N was not applied. The grain and straw yield was significantly correlated with the acetylene reduction activity in flooded soils and in the root system during the tillering and maximum tillering stages of rice growth, respectively. 相似文献
108.
U Saha 《Journal of the Association of Official Analytical Chemists》1987,70(4):686-688
A simple, sensitive, and rapid colorimetric method is presented for the estimation of tetracycline hydrochloride as the pure drug and in formulations. The proposed method is based on the reaction of tetracycline HCl with cupric chloride in an alkaline medium to give a yellowish green solution whose absorbance is measured at 400 nm against a reagent blank. The color obeys Beer's law in the concentration range of 0-20 micrograms/mL. Molar absorptivity and Sandell's sensitivity of the yellowish-green copper complexes of tetracycline HCl are 1.99 X 10(4) L X mol-1 X cm-1 and 0.0241 ppm, respectively. 相似文献
109.
Leonardo S. S. Oliveira Muhamad A. Saha Fahimeh Jami Rianza Asfa Maggie V. Maretha Jaliaman Sipayung Marthin Tarigan Alvaro Duran 《Forest Pathology》2023,53(5):e12825
Powdery mildews are biotrophic ascomycetes that do not typically kill their hosts, but instead interfere with normal plant growth. In Indonesia, white powdery spots were observed forming on the upper part of fully developed leaves of Eucalyptus pellita planted in sand beds of a clonal nursery. Thus, this study aimed to identify the causal agent of eucalypt powdery mildew in Indonesia as well as to develop control strategies to better manage the disease. Pathogen identification was based on morphology, molecular characterization of DNA sequencing the ITS region and pathogenicity test. In addition, considering that some powdery mildews are inhibited by free moisture on leaves, efficacy of foliar watering was tested for disease control. Phylogenetic analyses showed that isolates collected from infected eucalypt plants grouped together with other sequences of the Erysiphe elevata clade with bootstrap support of 99%; a similar result was also confirmed by morphological observations. Pathogenicity of powdery mildew on eucalypt plants was confirmed through artificial inoculation, thus fulfilling the Koch's postulates. For disease control, foliar watering reduced the incidence of powdery mildew on mother plants. The reduction of the disease incidence began to be more evident at 2 weeks after trial establishment, and in the fourth week, the incidence was below 10% in all three treatments, while the control was above 20%. Therefore, we concluded that E. elevata is the causal agent of powdery mildew in Indonesia and that one application of foliar watering per week was enough to minimize the disease impact in the nursery. 相似文献
110.
Analysis of existing agroforestry practices in Madhupur Sal forest: an assessment based on ecological and economic perspectives 总被引:1,自引:0,他引:1
A study was conducted in Madhupur sal forest of Tangail, Bangladesh to identify the suitable agroforestry practices of the
area. Considering the ecological aspects of different agroforestry practices 10 sample plots (10 m × 10 m) from each land
uses were taken, including natural forest to get a comparative scenario. The study showed that among the different agroforestry
practices, Margalef and Shannon-Weiner index values are the maximum for pineapple agroforestry and lower for banana agroforestry,
and Evenness index value is the maximum for lemon agroforestry. Determination of tree biomass in different land uses revealed
that it is highest (3 078.6 kg/100 m2) in natural forest followed by pineapple agroforestry, lemon agroforestry and banana agroforestry. Soil pH, moisture content,
organic matter, organic carbon, phosphorus and total nitrogen showed statistically significant variation while bulk density,
particle density, sulphur and potassium did not show any statistically significant variation among the land uses. Soil fertility
status showed that pineapple agroforestry is more fertile than rest of other land uses. The Net Present Value (NPV) indicated
that banana agroforestry is financially more profitable than other two systems, while the Benefit-Cost ratio (BCR) is higher
in pineapple agroforestry (4.21 in participatory agroforestry and 3.35 in privately managed land). Even though banana agroforestry
gives higher NPV, capital required for this practice is much higher. The findings suggest that pineapple agroforestry has
a tendency towards becoming ecologically and economically more sound than other two practices as it has better ecological
attributes and required comparatively low investment. 相似文献