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11.
This study was completed to evaluate the effect of fenugreek seed (Trigonella foenum; FS) and asparagus root (Asparagus officinalis; AR) on in vitro nutrient digestibility and fermentation patterns. Different levels [0%, 5%, 10%, 15% and 20% of dry matter (DM)] of the medicinal plants were included using alfalfa hay (AH) as a basal substrate at different incubation times (12, 18, 24 and 48 h). Total phenolic components of AH, FS and AR were 5.9, 10 and 8.3 g/kg DM, whereas total tannins were 0.4, 3.8 and 1.5 g/kg DM, respectively. Corresponding values for saponins were 10.4, 27.3 and 40.3 g/kg DM. Fenugreek seed increased (p < 0.05) in vitro organic matter (OM) digestibility at different incubation times and decreased (p < 0.05) crude protein (CP) digestibility at 18 and 24 h of incubation. Asparagus root also increased (p < 0.05) in vitro OM digestibility and decreased (p < 0.05) CP digestibility at different incubation times. Neutral detergent fibre digestibility was increased (p < 0.05) by the addition of AR or FS at low levels, but decreased (p < 0.05) noticeably by increasing level of two plants in the basal substrate. Ammonia‐N concentration was markedly reduced (p < 0.05) by the addition of AR at different incubation times, and this reduction was accompanied by the decrease in CP digestibility. True DM degradability and partitioning factor (ratio of substrate DM truly degraded to gas volume produced at different times of incubation) were increased, and total volatile fatty acid concentration and total gas production were decreased (p < 0.05) with the addition of FS (at 10% and 15% DM levels) or AR (at 5%, 10% and 15% DM levels) at different incubation times. Results suggest that FS and AR may have potential as feed additives to increase the efficiency of nutrients’ utilization, particularly of nitrogen in ruminant diets.  相似文献   
12.
The potato tuberworm, Phthorimaea operculella (Zeller), is an important insect pest of potato, Solanum tuberosum L., both in storage and in the field. In this research, tubers of eight commercial potato cultivars and four Iranian selections with equal weight and dormancy were exposed to 10 pairs of adult P. operculella in a climate chamber set at 25?±?1 °C, 65?±?5 % RH and total darkness. In a free-choice situation, oviposition was lower on 397082–2, Khavaran and Morene compared to the other germplasm that were exposed to adults of P. operculella. Number of mines per tuber, length of mines per tuber, time of development of larvae, number of pre-pupae produced per tuber, weight of pre-pupae and number of eggs developed in ovaries per female were counted and/or measured on each commercial cultivar and selection. There were fewer and shorter mines on tubers of 397082–2, Khavaran and Morene compared to the other potato germplasm. The number of pre-pupae produced per tuber and the weight of pre-pupae were lower when P. operculella was reared on tubers of 397082–2, Khavaran and Morene. Also the development, survival and fecundity were lower when P. operculella was reared on those same germplasm. Flesh firmness was negatively correlated with larval survival (r 2?=?0.87); in addition, the percentage of starch and macronutrient composition was low on these three germplasm. Thus, tuber flesh firmness of these germplasm could delay larval penetration and lower establishment 397082–2, Khavaran and Morene showed promising traits that can be integral component of potato breeding for resistance to P. operculella and pest management programs.  相似文献   
13.
Cobalt ferrite nanocrystals were prepared from an aqueous solution containing metal nitrates and various of concentrations of poly(vinyl pyrrolidone), followed by calcinations temperature. X-ray diffraction (XRD) analysis was performed to determine the degree of crystallinity of the ferrite nanoparticles. By transmission electron microscopy (TEM), the morphology and average particle size of the cobalt ferrite nanoparticles were evaluated which had good agreement with XRD results. Fourier transform infrared spectroscopy (FT-IR) suggested the presence of metal oxide bands in all samples as well as the effective elimination of organic constituents after calcinations. Vibrating sample magnetometer (VSM), was utilized to evaluate the magnetic properties of the cobalt ferrite nanoparticles.  相似文献   
14.
The effects of temperature, wetness and darkness on formation of pseudothecia and the effect of temperature on the release of ascospores of L. maculans on oilseed rape stubble were studied in a controlled environment in South Australia. Pseudothecia of L. maculans developed at 5–20°C and the time taken to reach maturity and discharge ascospores decreased from 58 days at 5°C to 22.2 days at 15°C. The optimum temperature of those tested for pseudothecium maturation was between 15°C and 20°C but fewer pseudothecia were observed at 20°C than at 15°C. Exposure to a 12 h photoperiod enhanced pseudothecium formation on the stubble compared with continuous darkness. No pseudothecia formed on stubble moistened once a day at 15°C, whereas three sprays of water per day decreased maturation time in comparison with two sprays per day. More ascospores were released for a longer duration at 20°C than at 5–15°C, although peak sporulation occurred earlier at 5–10°C than at 20°C. These findings highlight the importance of moisture, temperature and light for production and release of inoculum from stubble. This information, combined with field data, may help to predict the onset of inoculum release.  相似文献   
15.
The thermal treatment method was employed to achieve higher homogeneity of calcium ferrite (CaFe2O4) and Poly (vinyl alcohol) (PVA) nanocomposites. The influences of phase transformation on physical and biological properties of calcined specimens were investigated by various experimental techniques including X-ray diffraction (XRD), Transmission Electron Microscopy (TEM), high resolution Field emission scanning electron microscope (FESEM) and Fourier transform infrared spectroscopy (FT-IR). Heat treatment was conducted at temperatures between 723 and 923 K, so that a phase transformation occurred from cubic to orthorhombic spinel structure at 923 K. The chemical analysis of the PVA/CaFe2O4 nanocomposite was performed by energy dispersion X-ray analysis (EDXA), demonstrated the PVA/CaFe2O4 nanocomposites contained the elements of C, Ca, Fe, and O. The formed nanocomposites exhibited ferromagnetic behaviors which were confirmed by using a vibrating sample magnetometer (VSM). The calcined specimens were carried out to an antimicrobial or antifungal test.  相似文献   
16.
The aim of present study was to investigate the effect of onion (Allium cepa) peel hydroalcoholic extract (OPE) on rat hypertension induced by high-fructose diet and aorta contractility. The OPE was prepared by maceration method using 70% ethanol. The thoracic aorta from male adult rat (Wistar) was dissected and suspended in Krebs-Henseleit solution under 1 g resting tension. Tissue preparation was contracted by KCl (80 mM) or phenylephrine (Phe, 1 microM) and then the extract was applied cumulatively (0.0625-2 mg mL(-1)). Hypertension was induced in negative control and three groups of rats by adding fructose (10% WN/V) in drinking water for 6 weeks but control group received tap water. Hypertensive groups received saline or OPE at 200, 400 and 800 mg kg(-1) daily for last 3 weeks by gavage. Results showed that OPE reduces aorta contractions induced by KCl or Phe in a concentration-dependent manner (p < 0.001). Removing aorta endothelium did not attenuate the OPE activity. Inhibition of nitric oxide, cGMP and prostaglandin synthesis by L-NAME (100 microM), methylene blue (10 microM) and indomethacin (10 microM), respectively, did not attenuate OPE activity. Atropine abolished ACh-induced relaxation in Phe precontracted aorta but not the OPE-induced relaxation. Although the extract did not change heart rate but after 3 weeks reduced the hypertension induced by fructose (p < 0.001). Present results indicated that OPE reduces aortic contractions possibly via inhibition of calcium influx but without involving NO, cGMP, endothelium and prostaglandins. The OPE hypotensive effect could be due to extract quercetin content, antioxidant activity and inhibiting vascular smooth muscle cells Ca2+ influx.  相似文献   
17.
The main objective of this study was to evaluate the potential protective effect of red Grape Seed Extract (GSE) on lead induced hypertension (HTN) and Heart Rate (HR) in male Wistar rats. The rats were randomly assigned to one of 4 groups: Each group received lead acetate (100 ppm in drinking water), GSE (100 mg kg(-1), orally) or Lead + GSE for 45 days. Another group assigned as control group provided with tap water and regular pellet food. The Systolic Blood Pressure (SBP) and heart rate were determined by tail plethysmography coupled to a computer system. There was a sustained elevation of SBP in lead exposed rats that significantly increased at day 18 (lead treated, 112.7 +/- 2.7 mmHg, vs. control, 105.6 +/- 2.6 mmHg, n = 10, p < 0.05) and reached a maximum level at day 36 (lead treated, 124.9 +/- 2.3 mmHg, vs. control, 103.6 +/- 3.1 mmHg, n = 10, p < 0.001). However, the other three groups; showed no significant changes in SBP. Furthermore, the heart rate was increased sustainly in lead exposed animals that was statistically significant at days 36 and 45 (lead treated group, 404.5 +/- 9.4 vs. control group, 381.7 +/- 6.7, n = 10, p < 0.05). The blood lead level in both lead and lead + GSE treated groups was increased significantly compared with control and GSE treated groups (p < 0.001). However, GSE administration had no effect on the blood lead level in lead treated group. According to the result of this study, it may be concluded that GSE could have beneficial effect in protecting the cardiovascular system through its antioxidant activity against oxidative stress.  相似文献   
18.
The main four seaweed species for carrageenan production used in industry are Eucheuma denticulatum, Kappaphycus alvarezii, Chondrus crispus, and Sarcothalia crispata. In addition, a fifth red seaweed, Furcellaria lumbricalis, is a source of furcellaran, which is very similar to carrageenan. In this study, the chemical composition including total lipid, fatty acid profile, tocopherol content, total protein, amino acid profile, and total phenolic content of the five semi-dried industrial red seaweeds were analyzed. The obtained results indicated that when considering the total commercial production of carrageenan, there is potential to develop a method to extract protein before the main process for carrageenan extraction. Protein was the most considerable compound in the selected seaweed, and it varied from 4% for E. denticulatum up to 28% for F. lumbricalis. In the future, this may lead to a multi-product extraction (biorefinery) approach to result in more than one product instead of the traditional single-product procedure.  相似文献   
19.

Background:

Apolipoprotein A2 (APOA2) is the second major apolipoprotein of the high-density lipoprotein cholesterol (HDL-C). The study aim was to identify APOA2 gene variation in individuals within two extreme tails of HDL-C levels and its relationship with HDL-C level.

Methods:

This cross-sectional survey was conducted on participants from Tehran Glucose and Lipid Study (TLGS) at Research Institute for Endocrine Sciences, Tehran, Iran from April 2012 to February 2013. In total, 79 individuals with extreme low HDL-C levels (≤5th percentile for age and gender) and 63 individuals with extreme high HDL-C levels (≥95th percentile for age and gender) were selected. Variants were identified using DNA amplification and direct sequencing.

Results:

Screen of all exons and the core promoter region of APOA2 gene identified nine single nucleotide substitutions and one microsatellite; five of which were known and four were new variants. Of these nine variants, two were common tag single nucleotide polymorphisms (SNPs) and seven were rare SNPs. Both exonic substitutions were missense mutations and caused an amino acid change. There was a significant association between the new missense mutation (variant Chr.1:16119226, Ala98Pro) and HDL-C level.

Conclusion:

None of two common tag SNPs of rs6413453 and rs5082 contributes to the HDL-C trait in Iranian population, but a new missense mutation in APOA2 in our population has a significant association with HDL-C.  相似文献   
20.
In vitro, applications of nanosilicon dioxide (SiO2) and chitosan were investigated for their effects on growth and proliferation of apple (Malus domestica Borkh. ‘Gala’) explants under osmotic stress induced by agar to simulate drought stress and under non-stressed conditions. The experiment included five levels of SiO2 (0, 25, 50, 100, and 200 mg L?1), two levels of chitosan (0 and 40 mg L?1), and two levels of agar (7 g L?1 and 9 g L?1) added to Murashige and Skoog medium. Under non-stressed conditions (7 g L?1 agar), application of SiO2 at 50 or 100 mg ?1 increased proliferation of apple explants. Use of 50 or 100 mg L?1 SiO2 or 40 mg L?1 chitosan increased growth of apple explants under osmotic stress (9 g L?1 agar). This research suggests that use of SiO2 or chitosan may improve plant growth and tolerance to stress.  相似文献   
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