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81.
In order to evaluate the variability of the soil profiles at two shapes (concave and convex) and five positions (summit, shoulder, back slope, footslope and toeslope) of a slope, a study of a virgin area was made in a Beech stand of mountain forests, northern Iran. Across the slope positions, the soil profiles demonstrated significant changes due to topography for two shape slopes. The solum depth of the convex slope was higher than the concave one in all five positions, and it decreased from the summit to shoulder and increased from the mid to lower slope positions for both convex and concave slopes. The thin solum at the upper positions and concave slope demonstrated that pedogenetic development is least at upper slope positions and concave slope where leaching and biomass productivity are less than at lower slopes and concave slope. A large decrease in the thickness of O and A horizons from the summit to back slope was noted for both concave and convex slopes, but it increased from back slope toward down slope for both of them. The average thickness of B horizons increased from summit to down slopes in the case of the concave slope, but in the case of convex slope it decreased from summit to shoulder and afterwards it increased to the down slope. The thicknesses of the different horizons varied in part in the different positions and shape slopes because they had different plant species cover and soil features, which were related to topography.  相似文献   
82.
Background:This study investigated the antinociceptive effect of cumin and its biosynthesized AuNPs. Methods:Cumin extract (E) and cumin-AuNPs (GN) were prepared and administered intraperitoneally at the concentrations of 200, 500, and 1000 mg/ml to 27 male rats. UV–Vis spectroscopy and AFM were applied for AuNPs synthesis confirmation. The nociceptive behavior was assessed, and IL-6 serum levels were measured. Results:Cumin-AuNPs showed a peak absorption of 515 nm, and a size of about 40 nm. Three different concentrations of extract had no significant effect on acute and chronic nociceptive behavior. GN + E200 (46.00 ± 10.59) showed a significant acute anti-nociceptive effect compared to the control (98.66 ± 4.91; p = 0.029) and SS300 (98.33 ± 20.30; p = 0.029) groups. Also, GN + E500 (42.00 ± 11.84) significantly reduced acute nociceptive behavior compared to the control (98.66 ± 4.91; p = 0.019), SS300 (98.33 ± 20.30; p = 0.020), and GN + E1000 (91.00 ± 26.00; p = 0.040) groups. IL-6 serum levels reduced significantly in GN + E500 (24.65 ± 10.38; p = 0.002) and SS300 (33.08 ± 1.68; p = 0.039) compared to the controls (46.24 ± 3.02). Chronic nociceptive behavior was significantly lower in the SS300 (255.33 ± 26.30) compared to E200 (477.00 ± 47.29; p = 0.021), E500 (496.25 ± 46.29; p = 0.013), and GN + E500 (437.00 ± 118.03; p = 0.032) groups. Conclusion: Our findings suggest the potential effects of cumin-AuNPs on formalin-induced nociceptive behavior, which is independent of IL-6serum levels.Key Words: Interleukin-6, Pain, Cuminum cyminum L., Gold Nanoparticles, Green Synthesis  相似文献   
83.
84.
Summary The anaesthetic effects of intravenous tiletamine-zolazepam 6.6 mg/kg-ketamine 6.6 mg/kg (TK) and tiletamine-zolazepam 6.6 mg/kg-ketamine 6.6 mg/kg-xylazine 0.11 mg/kg (TKX) were evaluated in six wethers. Heart rate, respiration rate, arterial blood pressure, and the electrocardiogram were monitored during anaesthesia. Analgesia was tested by electrical stimulation in the left flank. Atropine (0.03 mg/kg) was given intramuscularly before induction, but after recording of baseline heart rate and respiratory rate. The duration of analgesia was 28.7 ± 6.9 min with TK and 82.8 ± 26.6 min with TKX. Heart rate increased significantly within 5 min after TK or TKX administration. Respiratory rate remained unchanged after TK administration, but increased significantly from 5 to 45 min after TKX administration. Arterial blood pressure decreased significantly at 15 min with TK and 30 min with TKX. Sheep remained recumbent for 201 min with TK and 166 min with TKX. All recovered uneventfully. We conclude that either TK or TKX may be used for anaesthetising sheep.  相似文献   
85.
The current study investigated the possibility of using the AMH concentration as a predictor of the ability of Korean Hanwoo cows to produce cumulus‐oocyte complexes, embryos that survive after transfer as well as the pregnancy outcome of surrogates. Eight sessions of ovum pick‐up (OPU) were performed with 19 donor cows at an interval of 3–4 days. Antral follicle count (AFC), oocyte quality and in vitro embryo development were recorded for each cow. Embryos produced from cows with different AMH profiles were transferred into recipients (n = 96). Cows in the high (≥0.25 ng/ml) and intermediate (0.1≥ to <0.25 ng/ml) AMH groups had a significantly higher AFC per OPU session (20.40 ± 1.36 and 16.91 ± 1.52, respectively; mean ± standard deviation) than cows in the low AMH group (<0.1 ng/ml; 12.19 ± 2.14). In addition, more cumulus‐oocyte complexes per donor were recovered in the high (11.46 ± 1.22) and intermediate (7.38 ± 0.83) AMH groups than in the low AMH group (4.77 ± 0.44). The percentage of oocytes reached blastocyst stage was significantly higher in the intermediate (47.0%) and high (38.5%) AMH groups than in the low AMH group (32.3%). The number of embryos produced per cow was higher in the high (3.9 ± 0.2) and intermediate (6.9 ± 0.6) AMH groups than in the low AMH group (2.2 ± 0.3). The percentage of embryos that gave birth to viable calves when transferred into recipients was higher for those derived from cows in the intermediate AMH group (50.7%) than for those derived from cows in the low (35.7%) and high (36.4%) AMH groups. In conclusion, a single measurement of AMH concentration predicted the in vitro embryo production potential of donor Korean native cows before OPU and is linked with embryo viability after transfer into recipients.  相似文献   
86.
The objective of this study was to evaluate the existence of Streptococcus equi subsp. equi and Streptococcus equi subsp. zooepidemicus as probable agents associated with naturally occurring infection of the equine upper respiratory disease in Mashhad area. Nasal swabs samples from thirty horses with upper respiratory tract infections were collected. The bacteria isolated and identified were Streptococcus equi subsp. equi (1 isolate), Streptococcus equi subsp. zooepidemicus (25 isolates), Pasteurella sp. (11 isolates), Staphylococcus sp. (17 isolates), Bacillus sp. (4 isolates), Pseudomonas sp. (4 isolates), Proteus sp. (1 isolate), Neisseria sp. (1 isolate) and E. coli (1 isolate). All 25 isolates of Streptococcus equi subsp. zooepidemicus and the isolate of Streptococcus equi subsp. equi were characterized by biochemical tests and molecular techniques. For molecular identification of the subspecies S. equi and S. zooepidemicus two genomic region SeM and sodA were amplified. This study is the first report of molecular identification of Streptococcus equi subsp. equi and Streptococcus equi subsp. zooepidemicus in Iran.  相似文献   
87.
Phytophthora root and stem rot of soybean is a destructive disease of soybean in Iran. Races 1 and 3 of pathogen have already been reported from two major growing regions of the crop, Lorestan and Golestan provinces. In a survey during 2004-2005, 142 isolates of P. sojae were recovered from infected plants and naturally infested soil samples using selective media and soybean leaf baiting technique. The majority of tested isolates (110 isolates) belonged to race one of P. sojae and 32 isolates belonged to race 3. ITS region of 23 isolates were amplified with specific primers Ps1 and Ps2. Sequences of this regions were similar to other gene banks sequences except two isolates from China. This survey showed low diversity in Iranian population of P. sojae.  相似文献   
88.
Background:Hearing loss, a congenital genetic disorder in human, is difficult to diagnose. WES is a powerful approach for ethiological disgnosis of such disorders. Methods:One Iranian family with two patients were attented in the study. Sequencing of known NSHL genes was carried out to recognize the genetic causes of HL. Results:Molecular analyses identified a novel stop loss mutation, c.1048T>G (p.Term350Glu), whitin the P2RX2 gene, causing a termination-site modification.This event would lead to continued translation into the 3'' UTR of the gene, which in turn may result in a longer protein product. The mutation was segregating with the disease phenotype and predicted to be pathogenic by bioinformatic tools. Conclusion:This study is the first Iranian case report of a diagnosis of ADNSHL caused by P2RX2 mutation. The recognition of other causative mutations in P2RX2 gene more supports the probable function of this gene in causing ADNSHL. Key Words: Autosomal dominant 41, Deafness, Mutation, P2RX2, Whole exome sequencing  相似文献   
89.
For the first time, the current study reports the genetic and phenotypic correlations between growth and reproductive traits in Zandi sheep. The data were comprised of 4,309 records of lamb growth traits from 1,378 dams and 273 sires plus 2,588 records of reproductive traits from 577 ewes. These data were extracted from available performance records at Khojir Breeding Station of Zandi sheep in Tehran, Iran, from 1993 to 2008. Correlations were estimated from two animal models in a bivariate analysis using restricted maximum likelihood procedure between lamb growth traits [birth weight (BW), weaning weight at 3 months of age (WW), as well as six-month weight (6 MW)] and ewe reproductive traits [litter size at birth (LSB), litter size at weaning (LSW), total litter weight at birth (TLWB), and total litter weight at weaning (TLWW)]. The genetic correlations between BW and reproductive traits varied from low to high ranges from 0.10 for BW–LSB to 0.86 for BW–TLWB. WW was moderately (0.37) to highly (0.96) correlated with all the reproductive traits. Moreover, the genetic correlations were observed between 6 MW and reproductive traits, varied from 0.19 to 0.95. Relationships between growth and reproductive traits ranged from 0.01 for BW–LSW to 0.28 for BW–TLWB in phenotypic effects. Results indicated that selection to improve WW would have high effect on genetic response in TLWW, and also, these results could be effective for all of the reproductive traits in Zandi sheep.  相似文献   
90.
Geopedology, using geomorphologic and supervised classification bases, has been proposed as a soil surveying method. It undertakes a systematic approach to map soilscapes. This approach tries to reduce the budget of accomplishing soil surveys as well as increasing the purity of mapping units. But to what extent it has been succeeded is the question. The main objective of this research was to validate the geopedological mapping methodology by statistical and geostatistical methods in the Borujen region, Central Iran. After a primary interpretation of the study area on air photos (1:20 000 scale), 94 pedons were excavated on a 125 m square sampling grid in the sample area for geostatistical studies. To achieve the statistical aims, a geomorphic unit which encompassed the maximum surface of the sample area (and also the study area) was selected and the biggest delineation of this unit with 19 pedons was considered. The credibility of generalizing the results of the geopedological approach for the studied unit was tested by comparison with 15 pedons in a similar unit outside the sample area, named the validation area. Properties of the soils, including percentage of clay, rock fragments (2–75 mm) and total carbonates in the soil family control section, percentage of organic matter in the A horizon and its thickness, were selected for statistical and geostatistical analyses. Univariate and multivariate statistical analyses obtained from the units in the sample and the validation areas, showed that the means of soil variables were similar. A high difference between A horizon thickness variances in the sample area and the validation area affected the significance of the variation test in the univariate and multivariate results. Our study demonstrated that, when comparing the same factors from sample and validation areas, the spatial distribution and spatial dependency level of soil attributes were different. Therefore, although the geopedological approach tries to distinguish more homogeneous soil mapping units, it is still not able to fully define and represent the real variability of soil properties and show the chaotic behavior or nature of the soils. We recommend further investigations on different techniques of stratifying the landscape in order to better analyze and understand the soil-forming processes and the nature of soil variability and to improve sampling and mapping approaches. We suggest that the additional determination of the phases of landforms and phases of soil series will improve mapping in the future.  相似文献   
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