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121.
In order to investigation the effects of Zn rates and application forms on protein and element contents (Fe, Cu, Mn, N and Zn) in bean plant, an experiment was conducted as a factorial based on completely randomized design at greenhouse conditions during 2006. Treatments were included zinc rates in 4 levels (10, 20, 30 and 40 mg Zn kg(-1) soil(-1) in ZnSO4 source) and 3 application forms (soil application, seed pelleting and foliar spraying). Results showed that Zn rates had significant effect on accumulation of Zn, Cu, Mn and N in bean leaves. Nitrogen accumulation in leaves reduced with increasing of zinc in the soil. Among Zn application forms, spray application had the highest accumulation of Fe, Zn and Mn in leaves (423.17, 282.89 and 88.17 mg kg(-1), respectively). The highest Zn content in seed was observed in 20 and 40 mg Zn kg(-1) soil(-1) levels (46.39 and 45.62 mg kg(-1), respectively). Meanwhile, all treatments of Zn (both rate and application) had not significant effects on Cu and Mn accumulation in bean seeds. According to interaction effects between Zn rates and application forms, the highest Fe content in seed was observed when 40 mg kg(-1) soil(-1) of Zn was applied as foliar spraying. The seed protein content nearly was stable while Zn levels was increased from 20 to 40 mg Zn kg(-1) soil(-1). Grain yield had significant correlation to zinc and Cu of leaves but, biomass had significant and negative correlation to Zn content of leaves at p < 0.05% probability levels.  相似文献   
122.
The potential using of Acute Phase Proteins (APPs) in the assessment of mammary gland health was studied by examining the levels of Fibrinogen (Fb) and Ceruloplasmin (Cp) in plasma and milk from dairy cows with different grades of mastitis. Plasma samples were taken from jugular vein and milk samples were collected from quarters of cows with subclinical and clinical mastitis, as well as healthy controls. California Mastitis Test (CMT) were performed on each udder quarter of cows for detection of CMT2+ and CMT3+ quarters. CMT (0) and culture negative cases were considered healthy cows. Clinical mastitis, was graded as mild (clots in milk) or moderate (clots in milk and visible signs of inflammation in the mammary gland/s). The concentrations of Fb in the plasma of the cows with subclinical and clinical mastitis were higher than in the plasma of the healthy cows (p<0.01). There was no significant difference in plasma concentration of Cp between healthy and subclinical groups (p>0.05), but differences between clinical and healthy groups were significant (p<0.05). The concentrations of Fb and Cp in the milk of the cows with subclinical and clinical mastitis were higher than in the milk of the healthy cows (p<0.01). The results indicated that measurement of Fb in plasma and milk and Cp only in milk might be suitable for early diagnosis of mastitis in dairy cows.  相似文献   
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124.
The oak decline is known as one of the most destructive complex diseases causing high economic losses around the world, especially in Iran. The main objective of the present study was to investigate the possible role of bacteria as causative agents of oak decline in the Zagros forests of Iran. To do this, stem, root and leaf samples were taken from symptomatic Persian oak trees (Quercus brantii) in different zones of Zagros forests (Ilam Province, Iran). From 150 bacterial isolates, 20 showed pathogenicity against Geranium seedlings. Among 20 hypersensitivity test positive strains, four strains showed pathogenicity against oak saplings. Based on morphological and 16S rRNA gene sequence analysis, three strains were identified as Bacillus pumilus and one strain as non‐sporulating Gram‐negative Stenotrophomonas maltophilia. Pathogenicity studies of different B. pumilus and S. maltophilia strains revealed that they have potential to cause the disease in oak saplings and symptoms of disorder in Persian oak trees. To our knowledge, there are no previous records of B. pumilus and S. maltophilia causing decline on Fagaceous trees like Q. brantii. More detailed field and molecular studies are required to confirm the absolute role of such bacteria in occurrence of oak decline in Zagros forests.  相似文献   
125.
1. The objective was to estimate heritability, genetic and phenotypic correlations for egg quality traits of Iranian native fowl at the Yazd Breeding Centre. 2. External and internal egg quality traits were measured on 1200 eggs from 794 hens of the 6th generation. A multivariate animal model with restricted maximum likelihood procedure was applied to estimate heritability, genetic and phenotypic correlations for egg quality traits using ASREML. 3. Heritability estimates for external egg quality traits ranged from 0·18 to 0·57 and for internal egg quality traits from 0·24 to 0·60. 4. For external egg quality traits, genetic correlation between egg weight and eggshell thickness (EST) was positive (0·36) and EST showed high genetic correlations with eggshell weight (0·84) and eggshell strength (0·55). This implies that heavier eggs tend to have thicker and stronger shells. 5. For internal egg quality traits, albumen height showed high positive genetic correlations with albumen weight (0·52), albumen index (0·98), yolk height (0·72) and yolk index (0·57). 6. Our results show that it is feasible to improve egg quality in Iranian fowl through selection for albumen height.  相似文献   
126.
We sought to determine the ultrastructure of pancreatic islet beta cells of streptozotocin-induced diabetic rats treated with oral vanadyl sulphate. Diabetes was induced in male Wistar rats by intravenous injection of 40 mg kg(-1) streptozotocin. The same volume of normal saline was injected in sham animals. Animals were divided into treated and control groups. Vanadyl sulphate was added to the drinking water of the treated animals at a concentration of 1 mg mL(-1) up to three months. Two months after vanadyl sulphate withdrawal animals were killed. Ultrastructure of islet beta cells were studied by transmission electron microscope. In diabetic treated rats plasma glucose and fluid intake returned to normal levels within three months while control animals remained diabetic. Well granulated cytoplasm, well developed endoplasmic reticulum, increase in the number of immature granules in the cytoplasm with no clear signs of cell injury were found in the islet beta cells of diabetic treated rats. Lymphocyte filteration, nuclear picnosis, cytoplasmic vacuolization were found frequently in the islet beta cells of untreated diabetic rats. In conclusion as was evident in thin sections of panceatic islet beta cells of treated diabetic rats in this study, vanadyl sulphate through preserving islet beta cells structure and ultrastructure contributes in reversing diabetic signs and symptoms in streptozotocin induced diabetic rats.  相似文献   
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128.
This paper explores the salt-tolerance response of Melilotus species, a forage legume, based on tolerance/susceptibility indices, leaf water relations, leaf/root ion concentrations and multivariate (factor and function discriminate) analyses. In a greenhouse experiment, salinity-susceptibility of 12 accessions of Melilotus (M. albus, M. indicus, M. officinalis) in addition, two controls (alfalfa and Persian clover) were evaluated at 0 mM, 100 mM, 200 mM, and 300 mM of sodium chloride (NaCl). The experiment was conducted in a split plot design with two replications. Stress tolerance score (STS) was calculated based on tolerance/susceptibility indices. Salt-tolerant accessions were identified. An extracted bi-plot based on factor analysis confirmed the results of tolerance/susceptibility indices. There were significant correlations between STS and multivariate statistics. Root potassium cation (K+) concentration was higher in Melilotus species than the control species in all the salinity treatments. STS, root K+ concentration, leaf turgidity, and leaf succulence characteristics can be used for screening salinity-tolerance in Melilotus accessions. In all treatments, M. officinalis, M. indicus, and M. albus were salinity-tolerant species in descending order.

Abbreviations: Total biomass yield under control (Yp) and stress (Ys) mediums, geometric mean productivity (GMP), leaf area (LA), leaf tissue density (LTD), linear regression coefficient (b), mean productivity (MP), relative water content (RWC%), Succulence (S), specific leaf area (SLA), stress susceptibility index (SSI), stress tolerance index (STI), tolerance (TOL), water content at saturation (WCS), water saturation deficit (WSD), sodium chloride (NaCl), potassium cation (K+), sodium cation (Na+), analysis of variance (ANOVA), least significant difference (LSD), alfalfa control accession (CHA), Persian clover control accession (CHC), coefficient of variation (CV), statistics of factor (F) and discriminate function (D)  相似文献   

129.
In this study, we selected 180 accessions from different wild relatives of wheat (AegilopsTriticum species) and tested them in the presence of a tolerant and a sensitive control variety under well-watered and drought-stressed conditions. The results of analysis of variance for dry masses and all measured root traits showed that water regimes, accession and species main effects were highly significant. Drought stress significantly declined shoot dry mass (59.42%), root length (37.85%) and the total number of branch roots (36.25%), but increased the root-to-shoot ratio (75.00%), specific root length (64.19%) and root tissue density (29.46%). Principal component analysis for 182 individuals and 12 species groups identified two components that explained 75.67 and 82.39% of the total variation in dry mass and root traits under drought-stressed conditions, respectively. Taking together, our results identified 12 accessions with superior tolerance to drought stress. Remarkably, four species of wild relatives – Ae. cylindrica (DC genome), Ae. neglecta (UM genome), Ae. speltoides (B genome) and Ae. tauschii (D genome) – responded well to drought stress. The potential of these species could be used for molecular analysis such as marker assisted selection and gene mapping, ultimately aimed at breeding for root traits with improved adaptation to drought environments.  相似文献   
130.
This study was conducted to determine the prevalence, distribution pattern, and the Sarcocystis species involved in slaughtered water buffaloes (Bubalus bubalis) in the Khuzestan, Iran by macroscopic and histological examination. The esophagus, heart, diaphragm, tongue, masseter, and thigh muscles were investigated. Esophagus and thigh muscles of only 3 of the 100 examined water buffaloes (3%) were infected with macroscopic Sarcocystis, whereas at microscopic level Sarcocystis were found in 83 of the 100 examined animals (83%). The highest prevalence rate of microscopic cysts was found in masseter muscle (57.1%) and then followed by tongue, diaphragm, esophagus, heart, and finally, thigh muscles (30.0%). There was no significant difference between males (83.6%) and females (82.0%) or between two investigated age groups (≤2 years old, 78% versus >2 years old, 88%). Based on the size of the sarcocysts, thickness of the walls and location of the cysts, Sarcocystis buffalonis as a macroscopic form and Sarcocystis levinei and Sarcocystis dubeyi as the microscopic forms were diagnosed in the examined muscles of the buffaloes of this area. Sarcocystis fusiformis was not seen in the examined organs of these buffaloes. The high prevalence rate of microscopic Sarcocystis in this region indicates that dogs have a more significant role than cats in transmission of these protozoa.  相似文献   
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