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1.
A measure to evaluate performance in irrigation systems is analyzed using the mean square prediction error concept. In the context of irrigation system management, the term error means the deviation of actual performance from a reference performance. The measure assesses performance in terms of the management objectives of adequacy and dependability of water delivery and an equitable distribution among various water users. It provides an understanding of the management capacity to schedule and distribute water in an irrigation system. Application of the performance measure is demonstrated by evaluating performance of an irrigation system in the Northwest Frontier Province of Pakistan.  相似文献   
2.
AIM: To determine the function of peritoneal mesothelial cells on the inflammatory microenvironment by administration of endometrial cells,and further define the pathogenesis of endometriosis.METHODS: Homogenous mouse endometrial epithelial and stromal cells were injected into the peritoneal cavities of Swiss Webster mice.After 4,24,and 72 h,a number of endpoints evaluated: protein concentrations of cytokine MCP-1,IL-1 α,IL-6 in peritoneal lavage and gene expressions of MCP-1,IL-1 α,IL-6 in peritoneal mesothelial cells and macrophages.RESULTS: The intraperitoneal administration of endometrial cells increased the protein expressions of cytokines in the peritoneal lavage of the recipient mice,which increased at 4-hour points and subsequently decreased with time.Gene expressions of cytokines in peritoneal mesothelial cells paralleled with the protein quantities in peritoneal lavage.The peak time of gene expression of cytokines in peritoneal macrophages was at the 24-hour point.The endometrial epithelial cells stimulated stronger inflammatory responses in the peritoneal cavity than the endometrial stromal cells.CONCLUSION: The recipient mice have a non-specific inflammatory response to the presence of endometrial cells in the peritoneal cavity.Mesothelial cells may be the targets of early inflammatory stress initiated in the presence of endometrial cells.  相似文献   
3.
The effect of seed size on germination and seedling growth was assessed using cultivars of greengram and blackgram. Significant positive correlation was noticed between seed size and germination, seedling height, root length, primary leaf size and seedling weight. The possible advantages of choosing cultivars with heavier seeds for attaining better crop stand especially under rainfed situation are discussed.  相似文献   
4.
Photoperiod and temperature modulated the seasonal pattern of ovarian gene expression of P450 aromatase, Follicle-Stimulating Hormone receptor and Luteinizing Hormone receptor in Atlantic salmon broodstock.  相似文献   
5.
The ease with which seeds are detached from panicles is one of the early domestication traits. Genotypes with sticky panicles are hard to thresh, and whenever threshed, the grain tends to remain attached to the glume which reduces market value and processability. This study was conducted to determine the genetic mechanisms underlying the threshability trait in sorghum. Four seed parents and eleven pollinators differing for threshability were intercrossed in Design II mating scheme and the resulting hybrids and the parents were grown in four environments. Threshability was estimated as the ratio of seed yield to panicle weight (TW) and proportion of seeds without sticky glumes (TG). Variation was significant among the entries, inbreds and hybrids with GCA for TG and TW varying markedly. Mean TG for inbred and hybrids of low threshable genotypes was not markedly different indicating that threshability trait is under the control of additive genes with dominant or partially dominant effects. Segregation analysis indicates that the TG trait may be under the control of few major genes with approximately one to three loci affecting the trait.  相似文献   
6.
Combined effects of beta-glucan and lipopolysaccharide (LPS) on survival and immune response were studied in Cyprinus carpio that were challenged with the pathogen Aeromonas hydrophila. beta-Glucan from Saccharomyces cervisiae and LPS from a virulent strain of A. hydrophila were used in this study. Different concentrations of beta-glucan+LPS mixture were administered on days 1, 7, and 14 through different routes (intraperitoneal injection, bathing, and oral administration). Control and test fish were challenged by intraperitoneal injection of LD50 concentration of A. hydrophila on day 16 and subsequently, mortality and relative percent survival (RPS) were recorded. Intraperitoneal injection elicited 100% RPS even at the lowest concentration (100 microg beta-glucan+10 microg LPS); whereas, oral administration improved RPS rate of carps at higher concentration (1% beta-glucan+0.25% LPS). Bathing did not improve the RPS. Test animals injected with even the minimum dose of the immunomodulators (100 microg beta-glucan+10 microg LPS/fish) had a significant increase in total blood leukocyte counts and an increase in the proportion of neutrophils and monocytes. Superoxide anion production by macrophages was also elevated, which presumably aided the efficient killing of bacterial pathogen. Lower concentration of beta-glucan+LPS had an adjuvant effect on antibody production as pretreatment by injection of 100 microg beta-glucan+10 microg LPS/fish resulted in higher antibody titer against A. hydrophila following vaccination. RT-PCR analyses showed that the expression of interleukin-1beta mRNA did not increase in test fish when compared with the control. Classical and alternative complement pathways were not affected by either the dose or the route of administration of the compounds. It may be concluded that intraperitoneal injection and oral administration, and not the bathing, of beta-glucan+LPS mixture in carp could enhance resistance to challenge by A. hydrophila through changes in several non-specific and specific immune responses.  相似文献   
7.
The present study was on assessment of the anti-parasitic activities of nickel nanoparticles (Ni NPs) against the larvae of cattle ticks Rhipicephalus (Boophilus) microplus and Hyalomma anatolicum (a.) anatolicum (Acari: Ixodidae), fourth instar larvae of Anopheles subpictus, Culex quinquefasciatus and Culex gelidus (Diptera: Culicidae). The metallic Ni NPs were synthesized by polyol process from Ni-hydrazine as precursor and Tween 80 as both the medium and the stabilizing reagent. The synthesized Ni NPs were characterized by Fourier transform infrared (FTIR) spectroscopy analysis which indicated the presence of Ni NPs. Synthesized Ni NPs showed the X-ray diffraction (XRD) peaks at 42.76°, 53.40°, and 76.44°, identified as 1 1 1, 2 2 0, and 2 0 0 reflections, respectively. Scanning electron microscopy (SEM) analysis of the synthesized Ni NPs clearly showed that the Ni NPs were spherical in shape with an average size of 150 nm. The Ni NPs showed maximum activity against the larvae of R. (B.) microplus, H. a. anatolicum, A. subpictus, C. quinquefasciatus and C. gelidus with LC50 values of 10.17, 10.81, 4.93, 5.56 and 4.94 mg/L; r2 values of 0.990, 0.993, 0.992, 0.950 and 0.988 and the efficacy of Ni-hydrazine complexes showed the LC50 values of 20.35, 22.72, 8.29, 9.69 and 7.83 mg/L; r2 values of 0.988, 0.986, 0.989, 0.944 and 0.978, respectively. The findings revealed that synthesized Ni NPs possess excellent larvicidal parasitic activity. To the best of our knowledge, this is the first report on larvicidal activity of blood feeding parasites using synthesized Ni NPs.  相似文献   
8.
Artificial breeding of mithun poses several challenges including lack of standard protocol for cryopreservation of spermatozoa. This is further complicated by harmful effects of hen's egg yolk (EY) as additive in extender. Purified low‐density lipoproteins (LDL) extracted from EY have been shown as beneficial over EY extender for long‐term semen storage in several species. This investigation explored use of LDL versus EY on semen quality and oxidative stress following freezing–thawing of spermatozoa. A total of 25 of 50 ejaculates based on biophysical parameters were selected for the experiment. After diluting with the Tris‐citrate‐glycerol (TCG) extender, each sample was split into three equal aliquots: Group I, control, EY; Group II and Group III contained 8% and 10% purified LDL, respectively. Frozen–thawed samples were evaluated for motility parameters (progressive, and in the bovine cervical mucus penetration test [BCMPT]), viability, sperm and nuclear abnormality, acrosome integrity, and enzymatic (leakage of intracellular contents) and biochemical (oxidative stress) profiles and in vitro fertility (IVF) assay. Study revealed a significant (< .05) improvement in viability, sperm and nuclear abnormality, acrosome integrity, motility (progressive and in cervical mucus), cholesterol content, and reduction in the leakage of intracellular enzymes in Group II. Moreover, intactness of acrosome and biochemical membranes was protected significantly (p < .05) in addition to significant (p < .05) improvement in binding per cent and binding index in IVF assay in extender containing 8% LDL. These results demonstrate that although cryopreservation of mithun's spermatozoa in EY was comparable with other species, addition of 8% LDL holds a clear advantage over EY or 10% LDL.  相似文献   
9.
This paper analyses the water management performance of small holder irrigation systems in Zimbabwe. The government and farmer managed systems are compared in terms of their ability to match desired with actual water supply. Desired supply is defined as crop water requirements adjusted downwards by rainfall where relevant. The Theil measure of accuracy of forecasts is used to calculate the error committed by each system in trying to match water supply and demand. The analysis shows that, everything else being equal, the farmer managed system performs better than the government system in matching supply and demand. This means that the farmer managed systems should be encouraged for future small holder irrigation development in Zimbabwe.  相似文献   
10.
The anionic nature and high cation exchange capacity (CEC) of clinoptilolite zeolite can be exploited to reduce ammonia (NH3) loss from urea and to improve soil chemical properties to increase nutrient utilization efficiency in lowland rice cultivation. A closed-dynamic airflow system was used to determine NH3 loss from treatments (20, 40, and 60 g clinoptilolite zeolite pot?1). Seed germination study was conducted to evaluate the effects of clinoptilolite zeolite on rice seed germination. A pot study was conducted to determine the effects of clinoptilolite zeolite on rice plant growth variables, nutrient uptake, nutrient recovery, and soil chemical properties. Standard procedures were used to determine NH3 loss, rice plant height, number of leaves, number of tillers, dry matter production, nutrient uptake, nutrient recovery, and soil chemical properties. Application of clinoptilolite zeolite (15%) increased shoot elongation of seedlings and significantly reduced NH3 loss (up to 26% with 60 g zeolite pot?1), and increased number of leaves, total dry matter, nutrient uptake, nutrient recovery, soil pH, CEC, and exchangeable Na+. Amending acid soils with clinoptilolite zeolite can significantly minimize NH3 loss and improve rice plant growth variables, nutrient uptake, nutrient recovery, and soil chemical properties. These findings are being validated in our ongoing field trials.  相似文献   
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