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101.
Previous serological surveys have reported the presence of different organisms in cats from Spain but little reports exist about the exact identity of these organisms. The purpose of the study reported here was to assess the presence of DNA of several vector-borne infections in a population of cats from Barcelona area. One hundred blood samples obtained from cats admitted to the UAB-VTH were entered into the study and classified as healthy (n=48) or unhealthy (n=52). EDTA-blood samples were assayed for Leishmania infantum, Ehrlichia spp., Anaplasma spp., Rickettsia spp., Bartonella spp., Hepatozoon spp., Babesia spp. and Theileria spp. DNA by means of PCR amplification and amplicons obtained were sequenced. Prevalence of infectious agents found were Leishmania infantum (3%), Ehrlichia/Anaplasma sp. (1%), Hepatozoon felis (4%) and Bartonella clarridgeiae (1%). Cats being less than 5 years old had more probability of having at less one PCR positive result (P=0.028). The results of this study show a low prevalence of several vector-borne pathogens among cats from Barcelona area. Although higher feline seroprevalences are previously reported, they evidenced exposure and probably overestimate the real or active degree of infection. However, it is important to maintain a high index of suspicion on these infectious diseases, both in sick and asymptomatic cats, and molecular techniques could aid in the identification of these pathogens.  相似文献   
102.
This case report describes the diagnosis and resolution of an inter-vertebral disk prolapse in a 6-year-old ferret. No predisposing causes were found in the patient's history. A right hemilaminectomy, performed 1 week after presentation, was chosen to treat the patient surgically, and complete remission of clinical signs was achieved 2 months after presentation.  相似文献   
103.
This article describes atypical interstitial (Leydig) cell tumors in two cryptorchid horses. Ultrasonography allowed accurate localization of the cryptorchid testicles. Ultrasonographic features of the tumor are also presented and may be of value for the clinical diagnosis.Histopathological evaluation of testicular tissue after cryptorchidectomy revealed atypical evolving interstitial (Leydig) cell tumors. Clinically, the tumors reported here appear to have several similarities with the interstitial (Leydig) cell tumors described in the literature, which in most cases appear to be (1) cryptorchidism–induced tumors, (2) often benign and not enlarged, and (3) often associated with aggressive behavior. Although generally considered to be uncommon, equine testicular neoplasms may occur more frequently than previously thought. The use of ultrasonography may improve diagnosis.  相似文献   
104.
105.
Dominance of a resistance trait can be defined as a measure of the relative position of the phenotype of the heterozygote RS compared with the phenotype of the two corresponding homozygotes, SS and RR. This parameter has been shown to have primary importance in the dynamics of pesticide resistance evolution. Literature on insecticide resistance suggests that dominance levels in the presence of insecticide vary greatly from completely recessive to completely dominant. With insecticides, both the chemical applied and the dosages used have been demonstrated to affect the dominance. By contrast, almost all herbicide resistances have been found to be inherited as partially to totally dominant traits. This discrepancy between weeds and insects may partly result from the methodologies applied to measure the dominance, ie a single dose for herbicide versus several doses for insecticide. Using two well-known resistances (csr1-1 and csr1-2) to acetolactate synthase (ALS) inhibitors in Arabidopsis thaliana (L) Heynh (mouse-ear cress), we used several herbicide doses to determine the dominance level to six ALS-inhibiting herbicides. The dominance level in the presence of herbicide varied from completely dominant to completely recessive, depending on the resistance allele and the herbicide tested. The dominance of the csr1-1 and csr1-2 resistance alleles ranged from 0 (completely recessive) to 1.1 (dominant) and from 0 to 0.3 (partially dominant), respectively. The recessivity of some resistance alleles in the presence of herbicide could lead to the development of improved resistance management in order to delay or avoid herbicide resistance evolution, especially in the control of outcrossing weed species.  相似文献   
106.
The subtractive suppressive hybridization (SSH), a method that allows the identification of sequences that are present in one genome (tester) but not in the other (driver), is a promising technique for the comparison of Mycoplasma agalactiae pathogenic strains. The optimal conditions for SSH were established by subtracting the M. agalactiae type strain PG2 DNA from the M. agalactiae strain 5632 DNA. Because these two strains possess different vpma gene repertoires, 5632-specific vpma sequences (and possibly other 5632-specific sequences) were predicted to be retrieved by SSH. The subtracted tester DNA was PCR-amplified and cloned into the pGEM-T easy E. coli vector. Two independent libraries were generated and used to prepare individual probes that were tested by Southern blot with genomic DNA from various field isolates and mycoplasma reference strains. Sequence analysis of two overlapping clones showed that they potentially code for a large carboxyterminal portion of a new vpma ORF. Several DNA fragments homologous to insertion sequences were also found in 5632 and related strains. These preliminary data suggest that SSH is a powerful method to investigate differences between mycoplasma strains, and may be applied to molecular epidemiology, diagnostic, and host specificity or pathogenicity determinant discovery.  相似文献   
107.
Progression from the juvenile to mature phase in woody plants is accompanied by changes in characteristics as diverse as adventitious rooting capacity, leaf morphology, canopy architecture, wood anatomy and reproductive development. Many concepts of phase change, the intensity and duration of changes that occur during the phase transition, and the practical consequences of plant maturation for growth and development, are poorly understood. Little is known about the physiological and environmental control of maturation in woody plants compared with herbaceous plants, and reliable markers of phase state have only been developed for a few species, mainly conifers. Understanding the mechanisms and forms of phase change is a prerequisite for achieving maturation or rejuvenation for applications such as seed production or clonal propagation. This review describes concepts, terminology and consequences of phase change, combining theoretical and practical aspects of tree maturation that relate to clonal forestry.  相似文献   
108.

Context

In the Mediterranean area, different post-fire management strategies are used for coppices of resprouting species to promote a more regular forest structure, enhance plant growth, and reduce fire risk. However, the effects of these management treatments on forest-associated fauna are unknown, which in turn could be limiting their beneficial effects.

Aims

The aim of this work was to determine whether forest management of a recently burned area dominated by a vigorous resprouting tree species (Arbutus unedo L.) affects ant communities.

Methods

Ant communities, sampled using pitfall traps, were examined from unmanaged and selective thinning coppices of A. unedo. Ants are here used as bioindicators of ecosystem health and surrogates for other animal groups.

Results

Very limited effects of these post-fire management strategies on the structure and composition of ant communities were found. The lack of effects could be due to the reported small changes in physical conditions among treatments; or either, the most sensitive ant species to these post-fire management treatments might be the same ones affected by fire and, consequently, the ant species that would potentially be affected most were no longer in the study area.

Conclusion

The lack of any significant effects caused by these post-fire management practices on the associated fauna of A. unedo coppices points out the suitability of these treatments in these circumstances.  相似文献   
109.
1. This study evaluated the effects of canola meal in broiler diets on carcass yield, carcass composition, and instrumental and sensory analyses of meat.

2. A total of 320 one-day-old Cobb broilers were used in a 35-d experiment using a completely randomised design with 5 concentrations of canola meal (0, 10, 20, 30 and 40%) as a dietary substitute for soya bean meal.

3. Polynomial regression at 5% significance was used to evaluate the effects of canola meal content. The following variables were measured: carcass yield, chemical composition of meat, and instrumental and sensorial analyses.

4. The results showed that carcass yield exhibited a quadratic effect that was crescent to the level of 18% of canola meal based on the weight of the leg and a quadratic increase at concentrations up to 8.4% of canola meal based on the weight of the chest. The yield of the chest exhibited a linear behaviour.

5. The chemical composition of leg meat, instrumental analysis of breast meat and sensory characteristics of the breast meat was not significantly affected by the inclusion of canola meal. The chemical composition of the breast meat exhibited an increased linear effect in terms of dry matter and ether extract and a decreased linear behaviour in terms of the ash content.

6. In conclusion, soya bean meal can be substituted with canola meal at concentrations up to 20% of the total diet without affecting carcass yield, composition of meat or the instrumental or sensory characteristics of the meat of broilers.  相似文献   

110.
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