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71.
Sadeghi Seyed Abu Taleb Rokouei Mohammad Valleh Mehdi Vafaye Abbasi Mokhtar Ali Faraji-Arough Hadi 《Tropical animal health and production》2020,52(2):733-742
Tropical Animal Health and Production - Non-additive genetic effects are important to increase the accuracy of estimating genetic parameters for growth traits. The aim of this study was to estimate... 相似文献
72.
Reynolds JF Smith DM Lambin EF Turner BL Mortimore M Batterbury SP Downing TE Dowlatabadi H Fernández RJ Herrick JE Huber-Sannwald E Jiang H Leemans R Lynam T Maestre FT Ayarza M Walker B 《Science (New York, N.Y.)》2007,316(5826):847-851
In this millennium, global drylands face a myriad of problems that present tough research, management, and policy challenges. Recent advances in dryland development, however, together with the integrative approaches of global change and sustainability science, suggest that concerns about land degradation, poverty, safeguarding biodiversity, and protecting the culture of 2.5 billion people can be confronted with renewed optimism. We review recent lessons about the functioning of dryland ecosystems and the livelihood systems of their human residents and introduce a new synthetic framework, the Drylands Development Paradigm (DDP). The DDP, supported by a growing and well-documented set of tools for policy and management action, helps navigate the inherent complexity of desertification and dryland development, identifying and synthesizing those factors important to research, management, and policy communities. 相似文献
73.
The H3N2 triple reassortant (TR) influenza viruses emerged in swine in 1998 and then in turkeys in 2003. It was then hypothesized that these viruses crossed the species barrier and transmitted from pigs to turkeys. In previous work we identified viruses with different transmission behavior between the two species, of which A/turkey/Ohio/313053/04 (TK04) transmitted both ways between swine and turkeys, and A/swine/North Carolina/03 (SW03) did not transmit either way between the two species. Utilizing the 12-plasmid reverse genetics (RG) system, we rescued two viruses (TK04 and SW03) with potentially different transmission behavior between pigs and turkeys. Single gene reassortants (SGR) were generated by switching the hemagglutinin (HA) or the neuraminidase (NA) genes between both viruses, and were evaluated for replication in vitro (pig and turkey tracheal/bronchial epithelial cells) and in vivo (pigs and turkeys). RG-created TK04 replicated more efficiently than SW03 in vitro and in vivo. Additionally, TK04 exhibited better binding affinity to plasma membrane preparations (PMP) from pig and turkey tracheal/bronchial epithelial cells compared to SW03. In study with SGR viruses, the HA protein was found to be essential for TK04 virus transmission amongst turkeys, but not sole factor contributing to the efficient replication of virus in turkeys and pigs. Such findings further highlight the polygenic nature of influenza virus pathogenesis. 相似文献
74.
Mohammad Reza Dadpour Somayeh Naghiloo Seyed Hadi Peighambardoust Sima Panahirad Maryam Aliakbari Ali Movafeghi 《Scientia Horticulturae》2011
A comparative study of floral ontogeny in normal and double-flowered phenotype of Syringa vulgaris was conducted using the epi-illumination light microscopy. In the wild phenotype, floral differentiation starts with calyx inception and the formation of four sepals in orthogonal positions (two median and two lateral). The corolla emerges as a continuous ring-like structure leading to the appearance of four petal lobes alternating with the sepals. Androecium was formed by initiation of two stamen primordia in transverse plane and finally the bicarpellate gynoecium emerges in median position. In the case of the double-flowered lilac, there are supernumerary petals in an additional whorl. In double-flowered phenotype, a ring meristem is formed acropetally after the first petal whorl initiates. Stamens and carpels initiated similarly in double-flowered as well as in wild-type plants. However, position of stamens deviates from the typical transverse situation. It seems that the appearing of an extra petal whorl did not exhibit any adverse effect on the initiation of other whorls, in terms of organ identity. Therefore, it would be suggested that the double-flowered phenotype of Syringa represents a case of neoheterotopy, with formation of an extra petal whorl, rather than a case of homoheterotopy with transformation of an ancestral androecium whorl into petals. 相似文献
75.
Azadeh Hatef Hamid Niksirat Bagher Mojazi Amiri Sayed Mohammad Hadi Alavi & Mahmoud Karami 《Aquaculture Research》2007,38(11):1175-1181
Sperm density, mineral and organic composition of the seminal plasma and their physiological relationship were investigated in the Caspian brown trout (Salmo trutta caspius). To establish a rapid and accurate method for assessment of sperm density, three different techniques were used: sperm counting, spectrophotometry (at 480 nm) and determination of the spermatocrit. The seminal plasma contained 159.26±8.84 mM sodium (Na), 33.72±2.01 mM potassium (K), 133.04±5.96 mM chlorine (Cl), 1.68±0.2 mM calcium (Ca) and 0.988±0.13 mM magnesium (Mg). The following organic components were found: total protein 0.75±0.14 mg 100 mL−1, cholesterol 2.86±0.58 mg L−1 and glucose 3.81±1.04 mM L−1. The mean sperm density was estimated to be 3.3 × 109 spermatozoa mL−1. The spermatocrit (%) ranged from 25 to 52 in sperm samples. Highly significant linear relationships were found between sperm density and spermatocrit (R2=0.703, P<0.001) and sperm density and optical density (R2=0.909, P<0.001), indicating that optical density can be used as a quick and accurate method of estimating sperm density. Significant relationships were also found between sperm density and Ca, Mg and total protein of seminal plasma. A significant correlation was also observed between the Ca and Mg concentrations (R2=0.774, P<0.01). The following correlations were observed between mineral and organic components: total protein and Ca (R2=0.462, P<0.05), total protein and Mg (R2=0.518, P<0.05) and glucose and Cl (R2=0.374, P<0.05). These parameters should be considered when developing procedures for either artificial fertilization or for cryopreservation of sperm. 相似文献
76.
Alireza Abdanipour Taki Tiraihi Taher Taheri Hadi Kazemi 《Iranian Biomedical Journal》2013,17(4):214-220
Background: The present study was designed to evaluate the secondary microglial activation processes after spinal cord injury (SCI). Methods: A quantitative histological study was performed to determine ED-1 positive cells, glial cell density, and cavitation size in untreated SCI rats at days 1, 2, and 4, and weeks 1, 2, 3, and 4. Results: The results of glial cell quantification along the 4900-µm long injured spinal cord showed a significant increase in glial cell density percentage at day 2 as compared to other days. Whereas the highest increase in ED-1 immunoreactive cells (monocyte/phagocyte marker in rats) was observed at day 2 (23.15%) post-injury. Evaluation of cavity percentage showed a significant difference between weeks 3 and 4 post-injury groups. Conclusions: This study provides a new insight into the multiphase immune response to SCI, including cellular inflammation, macrophages/microglia activation, glial cell density, and cavitation. Better understanding of the inflammatory processes associated with acute SCI would permit the development of better therapeutic strategies. Key Words: Spinal cord injuries, Inflammation, Microglia, Macrophages 相似文献
77.
Effect of different levels of dried citrus pulp on performance,egg quality,and blood parameters of laying hens in early phase of production 总被引:1,自引:0,他引:1
Nazok Ahmad Rezaei Mansour Sayyahzadeh Hadi 《Tropical animal health and production》2010,42(4):737-742
Utilization of agricultural wastes in animal nutrition is a matter of great concern. Dried citrus pulp (DCP) is a potential
source of some valuable nutrients for animal and poultry. In an experiment with completely randomized design, the effect of
different levels (0%, 4%, 8%, 12%, and 16%) of DCP was evaluated on performance, egg quality, and blood parameters of laying
hens from 25 to 37 weeks of age. The birds were randomly allocated to five groups with six replicates and three birds in each
replicate. The results showed that with increasing the level of DCP up to 12%, there were no significant differences among
treatments for feed intake, egg production, egg mass, feed conversion ratio, final body weight, yolk index, and yolk color.
There were no significant differences between treatments in shell thickness, eggshell index, egg score, and Haugh unit. Utilization
of DCP up to 16% significantly increased serum glucose and high-density lipoprotein and reduced cholesterol, low-density lipoprotein,
and triglycerides (P < 0.05). Results of the present study indicated that use of 12% DCP in laying hen diets had no adverse effect on performance
and egg quality of laying hens in early phase of production. 相似文献
78.
Physiological,ionoregulatory, metabolic and immune responses of Persian sturgeon,Acipenser persicus (Borodin, 1897) to stress
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Seyyed Morteza Hoseini Lluis Tort Mohammad Hadi Abolhasani Hamid Rajabiesterabadi 《Aquaculture Research》2016,47(12):3729-3739
The physiological ionoregulatory, metabolic and immune responses of Persian sturgeon, Acipenser persicus, to acute stress were investigated. Water levels were lowered to the fish dorsal scutes, and fish were blood‐sampled before stress (pre‐stress), and 0, 6, 24 and 72 h after stress. Results showed that serum cortisol rapidly increased after stress, returning to initial levels at 24 h. Serum glucose significantly increased at 6 h, declining to the pre‐stress levels at 72 h. Serum triglyceride and cholesterol showed significant decreases at 0 h, then increasing to higher than the initial levels at 72 h. Serum T3 and T4 significantly decreased at 0 h and recovered at 72 h. Serum chloride levels showed no significant changes while serum calcium showed a significant increase at 0 h and a further increase until 72 h poststress. Serum total protein and alternative complement activity showed a significant initial decrease and recovery at 24 h with further increase at 72 h. Serum lysozyme activity increased significantly at 24 and 72 h after stress. Serum total immunoglobulin significantly increased at 0 h and peaked at 24 h. This is the first work showing thyroid hormone and immunological responses in Persian sturgeon subjected to stress, and the results show that this species follows a classical hormonal and energetic stress response, although, in the low range among the sturgeons. Although transient and moderate, confinement stress can induce significant changes in the innate immune response. 相似文献
79.
Application of plant growth regulator (PGR) may alleviate some negative effects of environmental stresses such as salinity. A controlled environment experiment was conducted to study barley (Hordeum vulgare L. cv. Reyhane) growth, yield, antioxidant enzymes and ions accumulation affected by PGRs under salinity stress conditions at Shiraz University during 2012. The treatments were PGRs at four levels—water (as control), cycocel (CCC, 19 mM), salicylic acid (SA, 1 mM), and jasmonic acid (JA, 0.5 mM)—and four salinity levels—no stress (0.67 dS m?1, as control), 5, 10, and 15 dS m?1, which were arranged in a factorial experiment based on completely randomized design with four replicates. The results showed that salinity stress significantly decreased plant height, peduncle length, leaf area, ear length, grain number, dry weight, grain yield, harvest index, potassium (K+) accumulation, and potassium/sodium (K+/Na+) concentration ratio, which were closely associated with stress severity. However, PGRs compensated some of these negative effects, so that SA foliar application had the most ameliorative effect. Salt stress also increased Na+ accumulation as well as the activity of peroxidase, catalase, and superoxide dismutase (SOD). Since ion discrimination and enhanced antioxidant enzymes are associated with salt tolerance, in this experiment PGRs application might have enhanced K+ accumulation and antioxidant enzyme activity. The activity of SOD and K+/Na+ ratio were found to be useful in salt tolerance manipulation in barley plants. 相似文献
80.
Azizzadeh M Shooroki HF Kamalabadi AS Stevenson MA 《Preventive veterinary medicine》2012,104(3-4):335-340
The objective of this study was to document mortality reasons and risk factors for mortality in dairy calves in the northeast of Iran. This was a prospective cohort study of calves born on ten commercial dairy herds from 21 March 2009 to 20 March 2010. A total of 4097 live calves were followed for 90 days after birth. For each calf details of sex, parity of the dam, type of parturition and season of birth were recorded. The interval (in days) from the date of birth to the date of death and the reason for death was recorded for those calves that died before 90 days of age. A Cox proportional hazards model, including a frailty term to account for unmeasured herd-level effects was developed to quantify the effect of factors associated with time to death. Two hundred and sixty-six (6.5%, 95% CI: 5.8-7.3%) of the 4097 live-born calves died or were euthanised before 90 days of age. The most important reasons for death were digestive tract disorders (58% of all deaths, 95% CI: 52-64%) followed by respiratory diseases (13% of all deaths, 95% CI: 9-17%). Calves exposed to dystocia at birth had 2.09 (95% CI: 1.49-2.92) times the daily hazard of death compared with calves born from a normal calving. The daily hazard of death for calves born in the summer was 1.93 (95% CI: 1.41-2.64) times greater than the hazard for those calves born in the autumn. Inclusion of the herd-level frailty term had a significant effect on hazard estimates indicating that the study herds were heterogeneous in the distribution of unmeasured herd-level factors influencing calf survival. Our results show that diarrhoea is the most important cause of calf mortality in dairy herds in this area of Iran and that environmental and management factors affect calf mortality rate. 相似文献