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1.
The spliceosome, a ribonucleoprotein complex that includes proteins and small nuclear RNAs (snRNAs), catalyzes RNA splicing through intron excision and exon ligation to produce mature messenger RNAs, which, in turn serve as templates for protein translation. We identified four point mutations in the U4atac snRNA component of the minor spliceosome in patients with brain and bone malformations and unexplained postnatal death [microcephalic osteodysplastic primordial dwarfism type 1 (MOPD 1) or Taybi-Linder syndrome (TALS); Mendelian Inheritance in Man ID no. 210710]. Expression of a subgroup of genes, possibly linked to the disease phenotype, and minor intron splicing were affected in cell lines derived from TALS patients. Our findings demonstrate a crucial role of the minor spliceosome component U4atac snRNA in early human development and postnatal survival.  相似文献   
2.
To determine the most efficacious midstorage hydration-dehydration treatment for preservation of vigour and viability of stored pea seeds ( Pisum sativum L.), cultivar Bonneville , three methods viz., soaking-drying, moisture equilibration-drying and moist sand conditioning-drying each at varying durations were evaluated. Irrespective of the durations of treatment, soaking-drying proved injurious. Though all durations of moisture equilibration excepting and 120 h outperformed the control, yet 48 h proved to be the best. Preconditioning with moist sand (5 % moisture content) with seed at a ratio of 1: 2.5 for different durations revealed 48 h to be the optimum, 72–96 h to be innocuous and thereafter injurious. Maintenance of membrane integrity and counteraction of lipid peroxidation may be the possible reasons for such beneficial effects.  相似文献   
3.
Sulphide is one of the known environmental stressors, which potentially binds to cytochrome C oxidase (COX), a key enzyme in the electron transport chain, thereby blocking oxygen transport and ATP production. To ascertain the toxic effects of sulphide on Pacific white shrimp, Penaeus vannamei, two distinct exposure experiments were carried out with varying concentration of sulphide (0–1 mg/L), dissolved oxygen (normoxia and hypoxia) and pH values (8.2, 6 and 5). The activity of enzymes viz COX, superoxide dismutase (SOD), phenoloxidase and lactate accumulation was investigated. Outer membrane integrity and COX monomer separation were also done with the isolated crude mitochondrial preparations. Results indicated a significant reduction (p ≤ .05) in COX enzyme activity in sulphide exposed treatments when compared to control. The reduction was more intense when pH levels were reduced under hypoxia condition. Lactate accumulation as a result of anaerobic metabolism was found to be higher in hypoxic treatments. No significant difference (p ≥ .05) was observed in superoxide dismutase activity between the treatments, whereas phenoloxidase activity significantly decreased at higher concentration sulphide. Separation of mitochondrial proteins resulted in the identification of ~205 kDa of COX monomer, and significant damage was found in outer membrane integrity under hypoxia and pH treatments. From this study, it is evident that at a given concentration, sulphide is toxic to P. vannamei, and in association with hypoxia and low pH, they further intensify sulphide toxicity. Our results indicated that sulphide toxicity should not be considered as a single factor, rather it should be a considered as combination of factors.  相似文献   
4.
The health of the pond environment in shrimp farming is important for sustainable and profitable aquaculture, in which sediment–water interface is the most important influencing area. With this objective, the key parameters of water and sediment at the interface was studied in shrimp ponds with varying salinities and compared with the surface water and soil to understand the variations and the underlying causes. Total ammonia nitrogen and total alkalinity were higher in water at the interface as compared to surface water, whereas pH, nitrite, oxide forms of nitrogen (NO3), phosphorus (PO4) and oxidizing bacteria were observed to be lower. There was no significant difference with respect to macrominerals such as sodium, potassium, calcium and magnesium between water at the interface and surface. These changes are profoundly influenced by the uppermost 1.0‐cm thick sediment layer, where the maximum transition of nutrients takes place with the water column. The outcome of the study highlights the effectiveness of water sampling for metabolites at the interface, which reflects at an early stage any potential deterioration of pond environment, which will help the farmer to initiate timely mitigation measures.  相似文献   
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Porcine circovirus type 2 (PCV2) is an economically important pathogen. It has been demonstrated that PCV2 DNA can be detected in boar semen by PCR; however, the biological relevance of this is unknown. The objectives of this study were to determine if semen positive for PCV2 DNA is infectious (1) in a swine bioassay, or (2) when used for artificial insemination. For the first objective, 4-week-old pigs were inoculated intraperitoneally with PCV2 DNA-negative (bioassay-control; n = 3), PCV2a DNA-positive (bioassay-PCV2a; n = 3), or PCV2b DNA-positive (bioassay-PCV2b; n = 3) raw semen, or PCV2 live virus (bioassay-positive; n = 3), respectively. Pigs inoculated with PCV2 DNA-positive semen and PCV2 live virus became viremic and developed anti-PCV2 antibodies indicating that the PCV2 DNA present in semen was infectious. For the second objective, three Landrace gilts were inseminated with PCV2 DNA-negative semen (gilts-controls) from experimentally-infected boars, and six gilts were artificially inseminated with semen positive for PCV2a DNA (gilts-PCV2a; n = 3) or PCV2b DNA (gilts-PCV2b; n = 3). Serum samples collected from the gilts in all groups remained negative for anti-PCV2 antibodies for the duration of the experiment. In addition, fetal serum samples from all 105-day-gestation fetuses were negative for anti-PCV2 antibodies or PCV2 DNA. Under the conditions of this study, PCV2 DNA-positive semen was not infectious when used to artificially inseminate gilts; however, it was demonstrated to be infectious in a swine bioassay model and therefore is a potential means of PCV2 transmission amongst swine herds.  相似文献   
8.
Excess PO 4 3? from agricultural subsurface drainage and runoff degrades the overall water quality of the receiving surface waters in a cumulatively damaging process known as eutrophication. In the past 25 years, PO 4 3? removal by industrial byproducts and minerals has received considerable attention because these materials are both abundant and inexpensive. In this study, the saturated falling-head hydraulic conductivity and phosphate removal capability of granulated blast furnace slag (GBFS), cement kiln dust (CKD), zeolite, silica sand, and coconut shell activated carbon (CS-AC) were assessed. GBFS, zeolite, silica sand, CS-AC, and 5:95% and 10:90% CKD/sand blends all exhibited hydraulic conductivities ??0.001 cm/s. GBFS and the CKD/sand blends exhibited >98% PO 4 3? removal while CS-AC removed 70?C79% of initial PO 4 3? concentrations. In contrast, silica sand and zeolite removed 21?C58% of PO 4 3? . The phosphate removal data for each material was modeled against the Langmuir, Freundlich, Temkin, Dubinin-Radushkevich, and Frumkin sorption isotherms to yield insight into possible removal mechanisms. Overall, GBFS, CKD, zeolite, silica sand, and CS-AC were sufficiently permeable and removed significant amounts of PO 4 3? and should be considered for use in treatment of agricultural effluent.  相似文献   
9.
Plant growth promotion by Azospirillum brasilense SM has been attributed to its indole-3-acetic acid (IAA) production. Analysis of IAA biosynthesis by this strain under nutrient stresses, likely environmental fluctuations and long-term batch cultures suggested that they significantly influenced this function, with some conditions (fluctuations in temperature) triggering IAA accumulation. In long-term batch cultures (of 30 days), the bacterial population was maintained at a specific cell density and produced IAA even after a sharp decline in population size, albeit fluctuations were observed in both the parameters. Long-term bacterial cultures under nitrogen starvation showed the same trend in cell viability; however, a continuous increase in IAA accumulation was seen over time. This study has shown that A. brasilense strain SM has the potential to be a competent rhizospheric bacterium as it can beneficially influence the growth of sorghum. Further, it also has the ability to promote the growth of a number of other plants like mung bean, maize, and wheat. The benefit of this characteristic of strain SM can be directly accrued to a range of plants with which it may associate so as to improve their yield.  相似文献   
10.
Studies were conducted on the influence of moisture stress at different growth phases, either alone or in combination, on seed yield, quality and longevity in groundnut, at Agricultural College and Research Institute, Coimbatore. At the end of each growth phase, irrespective of available soil moisture, plots were irrigated with a measured quantity of water to a depth of 5 cm, sufficient to raise the soil moisture content of top 30 cm layer to field capacity. Plots which received stress were not irrigated in the respective growth phases. Moisture stress during the combined reproductive phases, viz. flowering + pegging and pegging + maturity, had a mitigating influence on growth and yield to a greater extent than stress at other phases. Though water deficit at different growth phases had no impact on viability and vigour of fresh seeds, it helped to enhance the longevity and the greater the stress the better the storability. The conversion of oil into free fatty acids was least in seeds collected from stress. Membrane integrity as indicated by electrical conductivity and leachate amino acids were also minimal in seeds from stressed plots.  相似文献   
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