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11.
Background: Integrins are heterodimeric glycoprotein receptors that regulate the interaction of cells with extracellular matrix and may have a critical role in implantation. The aim of this study was to investigate the effect of ovulation induction on the expression of α4, αv, β1, and β3 integrins in mouse blastocyst at the time of implantation. Methods: The ovarian stimulated and non-stimulated pregnant mice were sacrificed on the morning of 5th day of pregnancy. The blastocysts were collected, and the expression of αv, α4, β1, and β3 integrins was examined using real-time RT-PCR and immunocytochemical techniques, then their ovarian hormones were analyzed at the same time. The implantation sites in uterine horns of other pregnant mice in both groups were determined under a stereomicroscope on the 7th day of pregnancy. Results: The results showed that the expression of αv, β1, and β3 integrins in both mRNA and protein levels was significantly lower in the ovarian stimulated group than the control group, and the maximum ratio of expression was belonged to β1 molecule (P>0.05). Conclusion: The implantation rate in superovulated mice was significantly lower than control mice. It was suggested that ovulation induction decreased the expression of αv, β1, and β3 integrins of mouse blastocysts. Key Words: Blastosyst, Integrins, Implantation  相似文献   
12.
Two diploid sugar beet genotypes of agronomical importance were transformed using Agrobactrium tumefaciens harboring pBI35Scry containing a synthetic cry1Ab gene. Leaf blade with attached shoot bases, a highly regenerative tissue, were used as explant substratum for transformation. PCR screening with cry1Ab-specific primers showed the presence of transgene in more than 50% of the regenerated kanamycin-resistant plants after treatment with the antibiotic. A transformation rate of 8.8–12.2% (depending on genotype) was achieved as revealed by genomic DNA dot blotting. The intact integration of transgene cassette into the genome was furthermore confirmed by Southern blot analysis. The expression of the cry1Ab gene encoding a truncated endotoxin (67 kDa) at about 0.1% of total soluble protein was achieved in the leaves of transgenic plants as shown by Western blot analysis. Bioassays under in vitro conditions with Spodoptera littoralis, one of the most important pests in sugar beet fields, demonstrated enhanced resistance against this pest. The inheritance of the inserted transgene was confirmed in F1 plants obtained through crossing of T0 plants with a cytoplasmic male sterile line. Transgenic plants are currently grown in a greenhouse and will be subjected to further bioassay analyses against other lepidopteran pests of sugar beet.  相似文献   
13.
A pot study was conducted to assess the combined effect of biochar (B) with compost (Com) and inorganic fertilizers (F) for improving nutrient acquisition and productivity of maize. Seven different treatments, including B (1% w/w), F (Recommended nitrogen, phosphorus and potassium (NPK): 60, 30 and 25 mg kg─1), Com (1.5% w/w), Com+F (1.5% + NPK), B+F (1% + NPK), B+Com (0.5% + 0.75%), B+Com+F (0.5% + 0.75% + NPK) along with a control (C) without B, Com and F were applied in pots with four replications. The results showed that growth and grain yield of maize increased by the application of B, Com and F compared with C, but B+Com+F was more effective than their sole application (i.e. B, Com and F). Highest leaf chlorophyll content, gas exchange attributes and nutrient concentrations: N, P and K in shoot and grains were observed, where B+Com+F was applied followed by Com+F > B+F > B+Com > F > Com > B > C. Soil properties such as soil organic carbon (SOC), N, P, and K were significantly increased, whereas soil pH was decreased by the combination of B with Com and F. Hence, application of B in combination with Com and F (B+Com+F) could be a good management strategy to enhance crop productivity and improve soil properties.  相似文献   
14.

Purpose

This study delineated the effect of calcium (Ca) and ethylenediaminetetraacetic acid (EDTA) addition on arsenic (As) accumulation and physiological attributes of Vicia faba L.

Materials and methods

Two separate experiments were performed. In the first experiment, V. faba seedlings, grown under hydroponic conditions, were exposed to three levels of As (25, 125 and 250 μM) in the presence and absence of three levels of EDTA (25, 125, 250 μM) and calcium (CaCl2: 1, 5 and 10 mM). The effect of EDTA and Ca on As accumulation and physiological attributes of V. faba was assessed by determining As contents in roots and shoot, chlorophyll contents, H2O2 contents, and lipid peroxidation in young and old leaves. In the second experiment, V. faba seeds were grown in As-contaminated sand culture using the same treatment plan.

Results and discussion

The accumulation and toxicity of As to V. faba plants increased with increasing As levels in nutrient solution. Arsenic exposure enhanced the production of reactive oxygen species (ROS) in both roots and leaves, which resulted in lipid peroxidation and decreased chlorophyll contents. The presence of both EDTA and Ca, in general, significantly decreased As accumulation by V. faba seedlings, Ca being more effective than EDTA. Both the amendments decreased As-induced reactive oxygen species (ROS) production and lipid peroxidation. In the case of chlorophyll contents, EDTA significantly decreased chlorophyll contents, while Ca significantly increased chlorophyll contents compared to As. The effect of all the treatments was more pronounced in roots than leaves and in young leaves compared to old leaves.

Conclusions

It is proposed that EDTA and Ca greatly affect As accumulation and toxicity to V. faba, and the effect varies greatly with their applied levels as well as type and age of plant organs. The germinating seedlings of V. faba may be preferred for risk assessment studies, while transplanting 1-week-old V. faba seedlings to As-contaminated soils can decrease its toxicity.
  相似文献   
15.
The effect of cattle manure and sulfur fertilizer on seed yield and oil composition of pumpkin (Cucurbita pepo var. Styriaca) under inoculated with Thiobacillus thiooxidans was investigated in a factorial study based on a randomized complete block design. Experimental factors consisted of cattle manure (M) (M0: 0, M1: 10; and M2: 20 t ha?1), sulfur (S) (S0: 0, S1: 250; and S2: 500 kg ha?1) and T. thiooxidans (B): inoculated (B1) and non-inoculated (B0). Results demonstrated that the application of T. thiooxidans, cattle manure, and S fertilizer decreased the soil pH. The largest number of seed per fruit (367), highest fruit yield (70.57 t ha?1), seed iron (Fe) content (16.26 mg 100 g?1), and seed yield (111 kg ha?1) was obtained when 20 t ha?1 manure was applied in combination with 500 kg ha?1 S inoculated with T. thiooxidans. In this condition, the content of S, Fe, phosphorus (P), and nitrogen (N) in plant shoots was increased by 44.8%, 22.58%, 33.89%, and 10.38%, respectively, compared to the control. Moreover, the highest content of seed protein was observed in 10 t ha?1 manure and 500 kg ha?1 S fertilizer inoculated with T. thiooxidans. When 250 kg ha?1 S fertilizer was applied, 20 t ha?1 manure decreased seed P content sharply. At the rate of 500 kg ha?1 S fertilizer, the highest content of seed P was obtained from 20 t ha?1 manure. Totally, 20 t ha?1 cattle manure, along with 500 kg ha?1 S fertilizer as well as T. thiooxidans inoculation, improved oil and seed yield of medicinal pumpkin.  相似文献   
16.
In this study, a new approach consisting of chemical treatment steps followed by electrospinning process was applied to produce cellulose nanofibers from wheat straws. Wheat straws were initially pretreated by NaOH solution to open the complex structure of raw materials and remove non-cellulosic materials. Then, acid and alkali hydrolysis was separately performed to eliminate hemicellulose and soluble lignin. Also, bleaching processes were implemented to remove the insoluble lignin. Cellulose nanofibers were produced by electrospinning of various concentrations of cellulose in different solvents including sodium hydroxide/urea/thiourea, pure trifluoroacetic acid (TFA), and TFA/methylene chloride. Images obtained by Scanning Electron Microscope (SEM) showed long and uniform nanofibers produced from electrospinning of cellulose/TFA/methylene chloride solution. An epoxy based laminated composite was prepared by a lamina of cellulose microfiber and electrospun nanofiber mat using hand lay-up composite manufacturing method. The fracture surface of the epoxy nanocomposite was analyzed by SEM images. In addition, the mechanical properties of laminated epoxy composites were compared with pure epoxy by conducting tensile and impact tests. Tensile test results showed that the ultimate tensile strength, elongation, and modulus of laminated epoxy nanocomposites were significantly increased. Moreover, it was found that by adding a nanofiber lamina in the epoxy composite, the impact resistance was significantly improved as a result of crack growth prevention.  相似文献   
17.
The aim of this study is to document the prevalence of HTN and characterize risk factors associated with HTN in Iranian hemodialysis patients. Three hundred and thirty seven HD patients from 5 university based HD centers around Iran were enrolled in the study. Urea reduction ratio was calculated using formula: 100 * (1-(urea before HD/urea after HD)). Pearson Chi-square test, independent sample t-test and one way ANOVA were used for evaluations, where appropriate. Multivariate logistic regression model was used for defining independent risk factors. Two sided p < 0.05 were considered significant. Patients with diabetes mellitus and hypertension as causes of ESRD significantly were more likely to have hypertension before and after dialysis (p < 0.05). Patients with conventional thrice weekly dialysis (compared to twice), hemodialysis duration of more that 6 months, acetate type of dialysate, ESRD cause when diabetes mellitus and hypertension, were significantly associated with having pre-HD hypertension. We also found that hemodialysis center of the capital city had a significant better measures compared to other cities (p < 0.05). This study revealed a relatively acceptable prevalence of hypertension in our HD population. Nevertheless, because of higher prevalence of HTN in HD centers out of capital city, it seems necessary that we should urgently pay more attention in promotion of these centers toward achieving better outcome with implementing strict guidelines to follow.  相似文献   
18.
In this study, in vitro organogenesis of Gladiolus grandiflorus cultivar pink corm segments were evaluated by culturing corm calli in modified MS medium supplemented with 3% sucrose and 0.7% agar with different concentration of BAP (0, 1, 2 and 4 mg L(-1) medium) and NAA (0, 0.5, 1 and 2 mg L(-1) medium) in factorial experiment of Completely Randomized Design (CRD). In order to obtain Gladiolus calli, corm segments (Aprox. 5 x 5 x 1 mm in size) were kept in modified MS medium (Murashige and Skoog, 1962) that was supplemented with 1 mg L(-1) 2, 4-D, 3% sucrose and 0.7% agar. The results showed that increasing the concentration of BAP from 0 to 2 mg L(-1) medium simulated plantlet regeneration but no significantly effect was obtained on shoot and cormel organogenesis between 2 and 4 mg L(-1) BAP concentration in medium. Increasing of NAA content in media without BAP developed rootlet significantly. Interaction results showed that increasing BAP content against decreasing of NAA concentration stimulates the shoot and cormel proliferation.  相似文献   
19.
The effects of different salinity levels, including 10–15, 30–35, 70–75, 110–115 and 150–155 ppt, were evaluated on survival and the body amino acids (BAA) of Artemia franciscana. The results were expressed as total essential (TE), non‐essential (NE) and total amino acids (TAA); also, the ratio of the TE to NE (ENAA) on days 3 and 13 of the culture is reported. The study of changes in Artemia BAA showed that with the increase in the water salinity, the TE, NE and TAA increased significantly on days 3 and 13 of the culture. However, the highest ratio of ENAA was observed in the 110 gL?1 salinity treatment on day 3 (1.067 ± 1.25). Regarding the effects of different salinity treatments on the survival rate of Artemia, it was observed that, generally, an increase in the water salinity would reduce the survival rate of this species. This reduction was observed on day 3 of culture in the salinity treatments above 120 (66.66 ± 1.68%) and below 30 gL?1 (89.66 ± 0.34%) and on day 13 of culture in the salinity treatments below 30 (11.86 ± 0.13%) and above 70 gL?1. Basically, it can be concluded that A. franciscana culture at a salinity of 110 gL?1 can lead to the biological enrichment of Artemia in terms of amino acid profile.  相似文献   
20.
In the present study, elastic properties of scarf-jointed oak (Quercus castaneifolia) timbers with the application of two different types of adhesives (polyvinyl acetate and isocyanate) were evaluated using free flexural vibration of free–free beam method in different flexural directions of vibration, i.e., tangential and redial directions. Samples were taken from trees of Hyrcanian forests in Iran with nominal dimensions of 20 × 20 × 360 mm3. Comparing the results of elastic properties of clear oak wood beams with scarf-jointed samples wood showed that scarf joints with the bonding angles of 70° and 75°, covered by polyvinyl acetate adhesive, did not demonstrate any significant effect on modules of elasticity. Scarf-jointed beams with smaller joint angles (60° and 65°) were considerably weaker or totally unreliable in their moduli of elasticity. It is also shown that the magnitude of effect gets worst by using isocyanate rather than polyvinyl acetate adhesive.  相似文献   
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