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51.
BACKGROUND: Veterinary clinical pathology is a relatively new and emerging discipline in Europe that has gained momentum with the recent establishment of a specialty college. In this situation, veterinary faculties may face challenges in understanding and defining what clinical pathology is and how it can best be integrated into existing curricula. In addition, many schools in Europe may not yet have available a critical mass of suitably qualified faculty capable of teaching in all areas of clinical pathology. OBJECTIVE: The main purpose of this report is to describe the goals, procedures adopted, teaching material produced, and proposed future activities of a major European initiative designed to develop a veterinary clinical pathology curriculum. METHODS: Four working subgroups were formed to establish a list of course objectives and topics and prepare a series of lectures. These contents were reviewed and discussed several times at a series of general meetings. RESULTS: An undergraduate course on veterinary clinical pathology was designed with course objectives, a list of topics and a CD-ROM consisting of 24 lectures. CONCLUSIONS: The results of this project could be useful in the establishment or improvement of training programs in veterinary clinical pathology at the undergraduate level in Europe and in other places around the world. The provision of teaching resources for faculty could help to instill in veterinary students a strong understanding of the discipline and promote development of advanced training programs and career opportunities in clinical pathology in Europe.  相似文献   
52.
An aerial trail of odorous pheromone molecules extends downwind from a female pink bollworm moth that is receptive for mating. Males apparently sense the boundaries of the trail during their characteristic zigzag flights across it. Contrary to previous beliefs, the mechanism by which the males steer toward the odor source does not require a sensing of wind direction.  相似文献   
53.
Application of organic materials to soils to enhance N immobilization into microbial biomass, thereby reducing inorganic N concentrations, was studied as a management option to accelerate the reestablishment of the native vegetation on abandoned arable fields on sandy soils the Kiskunság National Park, Hungary. Sucrose and sawdust were used at three different topographic sites over 4 years. N availability and extractable inorganic N concentrations were significantly reduced in all sites. Soil microbial biomass C and microbial biomass N increased significantly following C additions, but the microbial C to microbial N ratio remained unaffected. It is concluded that the combined application of the rapidly utilized C source (sucrose) promoted N immobilization, whereas the addition of the slowly utilized C source (sawdust) maintained the elevated microbial biomass C and microbial biomass N in the field.  相似文献   
54.
Investigations were made on four wheat (Triticum aestivum L.) lines under greenhouse conditions, in order to reveal the role of stress-protective materials, namely salicylic acid, polyamines and antioxidant enzymes in the level of tolerance to powdery mildew infection caused by Blumeria graminis (DC.) Speer f.sp. tritici ém. Marchal. The four lines showed different levels of tolerance, assessed on the Saari-Prescott scoring scale: TC26 and TC33 proved to be susceptible and TC9 and TC19 resistant. In most of the lines, infection caused changes in the activities of antioxidant enzymes, especially in the case of guaiacol peroxidase. Four peroxidase isoenzymes, which responded differently to powdery mildew infection could be detected by gel electrophoresis. Infection had only a slight effect on the levels of salicylic acid (free and bound forms) in inoculated plants; while the levels of polyamines, especially spermidine and spermine increased after infection. Correlation analysis was also performed to examine how close a relationship exists between the parameters investigated. It was concluded that salicylic acid, polyamines and antioxidant enzymes have an important role in plant responses and defence mechanisms during this biotic stress and that in some cases there were significant relationships between them. However the levels of these compounds either initially or after pathogen inoculation, could not explain the degree of tolerance to powdery mildew in the four wheat lines investigated.  相似文献   
55.
56.
The heading characters and morphological traits of two partial sets of wheat–barley disomic addition lines, namely Mv9kr1/Igri and Asakaze/Manas, were evaluated under controlled environmental conditions in a phytotron under long-day, short-day and non-vernalised conditions and in field-sown experiments. The winter barley chromosome additions significantly influenced the flowering time of wheat both in the controlled environment test and under field-sown conditions. Of all the barley addition lines, the effect of the 4H and 7H additions was the most characteristic. The 7H addition lines were the earliest in both cultivar combinations in each treatment. In the Mv9kr1/Igri combination the 4H addition was the latest under all the environmental conditions. In the Asakaze/Manas combination 4H addition was the latest under short-day and long-day illumination in the phytotron but the 6H addition was the latest without vernalisation and in the field in 2012. There was 12 and 11 days difference between the flowering times of the 7H and 4H Mv9kr1/Igri and Asakaze/Manas addition lines in the field in 2012, which increased to 52 and 44 days under short-day illumination in the phytotron. In the winter wheat background, the addition of 2H carrying the photoperiod sensitivity gene Ppd-H1 decreased the flowering time under the short photoperiod regime, but had a very strong delaying effect under field-grown conditions. Considering the yield components under field conditions, 4H was the most fertile of the addition lines, while 7H showed the highest tillering capacity, and Igri 3H had good tillering capacity and the highest number of seeds per plant.  相似文献   
57.
Helianthus tuberosus agg., an herbaceous perennial plant from the Asteraceae family, is native to North America and was introduced as a crop to Europe in the seventeenth century. The status of this plant has been rather controversial in the Carpathian Basin. This paper reviews its taxonomy, chorology, and ethnobotany in this region, using data obtained from herbarium specimens, ethnobotanical surveys performed in Transylvania, and data published earlier, documenting the invasive features of the plant since the beginning of the nineteenth century. Our results suggest that (1) Helianthus tuberosus agg. has been present in the Carpathian Basin from the nineteenth century, (2) its taxonomy is problematic since the first part of the nineteenth century; (3) ethnobotanical surveys confirmed that the plant’s tuber has been locally used mostly as a food in Transylvania, collected from cultivation. Overall, Helianthus tuberosus agg. is both a ‘blessing and a curse’ at the same time, it is a valuable crop with beneficial nutritional value, and also an environmentally dangerous invasive element for the diversity of the flora of the Carpathian Basin.  相似文献   
58.
Lice may serve as biological or mechanical vectors for various infectious agents. To investigate louse infestation of ruminants and pigs, and pathogens potentially transmitted by them, anopluran lice (n=1182) were collected in Hungary, and evaluated for the presence of anaplasma, rickettsia and haemotropic mycoplasma DNA. On cattle the following species were found: Linognathus vituli (57%), Haematopinus eurysternus (38%) and Solenopotes capillatus (5%). L. vituli had a lower mean individual count/host when compared to H. eurysternus. On calves only L. vituli was observed, with a higher louse burden than on full-grown cattle. H. eurysternus and S. capillatus were more likely to occur simultaneously with another species on the same host, than L. vituli. Goats infested with Linognathus stenopsis had the overall highest prevalence (68%), while pigs harbouring Haematopinus suis showed the lowest (<1%). Anaplasma DNA was detected in 50% of pools analysed. In L. vituli Anaplasma ovis (or a closely related novel Anaplasma marginale genotype) was identified. Anaplasma-positivity of H. suis suggests that pigs may extend the reservoir and/or host spectrum of relevant species. Anaplasma-infected L. stenopsis pools show for the first time that caprine anaplasmosis is endemic in Hungary. Rickettsia spp. were demonstrated from Linognathus spp. and H. eurysternus. No haemotropic mycoplasmas were detected in any samples. In conclusion, this is the first molecularly confirmed report of bovine and ovine Anaplasma spp. in L. vituli, L. stenopsis and H. suis. The present results suggest that phthirapterosis of domestic animals deserves more attention, and lice should be evaluated among the broad range of potential vectors of arthropod-borne pathogens.  相似文献   
59.
The aim of the present study was twofold. First, in general, to reveal new aspects of the potential vector role of ixodid ticks and fleas by screening large numbers of specimens with recently developed molecular biological methods. Second, to evaluate the occurrence of vector-borne infectious agents in a geographical context. Altogether 3442 unfed hard ticks (Ixodes ricinus, Dermacentor marginatus, D. reticulatus, Haemaphysalis inermis, H. concinna, H. punctata) and 939 fleas of cats and dogs (Ctenocephalides felis, C. canis, Pulex irritans) were collected in Hungary. DNA was extracted and analyzed in pools for representatives of the orders Rickettsiales and Mycoplasmatales.H. inermis was newly identified as the most important potential vector for Rickettsia helvetica in the study region. A novel Rickettsia genotype (designated ‘Candidatus R. hungarica’) was also detected in the same tick species, with a maximum of 95.8% gltA gene sequence identity to known rickettsiae. In addition, P. irritans tested positive for Rickettsia sp. RF2125, which has not been previously described in Europe. The human pathogen R. felis and the feline pathogen ‘Candidatus Mycoplasma turicensis’ were shown for the first time to occur in Central-Eastern Europe. Further novel findings include the presence of Spiroplasma spp. in D. marginatus and fleas. In conclusion, this molecular study extends the geographic range and vector spectrum of several arthropod-borne agents, some of which have zoonotic potential.  相似文献   
60.
The direct effects of ketamine-xylazine (KET-XYL) on vascular function have not been investigated in rabbits. The short-term cardiovascular effects of intravenous (IV) KET-XYL bolus injection, therefore, should be investigated using vascular ultrasonography.In this prospective experimental study, KET-XYL anesthesia was induced IV in 9 female New Zealand White rabbits before 3 defined test bolus injections of KET-XYL were given IV. Before and for 10 min after each KET-XYL injection vascular and hemodynamic variables were recorded at the left common carotid artery (ACC) after the 1st injection, and at the abdominal aorta (AA) after the 2nd injection. Echocardiography was performed after the 3rd injection to investigate changes in cardiac parameters.Ketamine-xylazine IV caused a significant increase in vessel diameter at the ACC and AA. Average volumetric flow significantly decreased at the ACC and pulsatility index significantly decreased at the AA. Fractional shortening (FS) and heart rate significantly decreased, while mean arterial blood pressure initially increased.Bolus injections of KET-XYL IV produced a transient vasodilatation at the ACC and AA. Despite central vasodilatation, bradycardia, and decrease of FS and average volumetric flow (VFave), mean arterial blood pressure did not significantly decrease indicating well-preserved cardiovascular compensatory mechanism after the ratio and doses of KET-XYL IV bolus injections used in this study.  相似文献   
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