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991.
We used thermal images of bamboo culms of Guadua angustifolia Kunth to analyze the relationship between culm surface temperature and maturity, driven by the hypothesis that young culms may exhibit lower surface temperatures than old ones. The culm surface temperature shows small but constant differences between three age classes of 1, 2, and 3 years. Our findings indicate that surface temperature may be applied as an additional indicator to support the determination of maturity of guadua culms besides the visual assessment of the culms. 相似文献
992.
Rinaldo Botondi Matteo Vailati Andrea Bellincontro Riccardo Massantini Roberto Forniti Fabio Mencarelli 《Postharvest Biology and Technology》2009,51(1):97-103
Little is known about the biochemistry of the marron (Castanea sativa cv Marrone fiorentino) when it is soaked in water for the curing process; the immersion treatment time is still empirical and based on traditional knowledge. A study was carried out by keeping marrons in water for 7 d at 14 °C. Tap water and acid water (pH 3) were used in the following water/marron ratios 1:1, 1:2, and 3:2. After curing, the marrons were moved to air storage at room temperature (20 °C and 90% RH) for 1 week (shelf-life), and at 0 °C and 90% RH for 60 d. A large accumulation of carbon dioxide in the head space of the glass jar where the marrons were kept, was observed during water soaking, above all in samples in acid water with a water/marron ratio 1:2. In the first 5 d of water curing, a significant increase in acetaldehyde concentration and phenol content was measured in the marron pulp and subsequently, both compounds declined. Ethanol decreased slightly or remained constant. During the following week of shelf-life, the lowest respiration rate was measured in 1:1 and 1:2 samples while the highest rate was measured in acid water samples. SSC (solid soluble contents) increased in marrons soaked in acid water but remained constant under shelf-life conditions. SSC, ethanol, acetaldehyde and polyphenols did not change following storage at 0 °C for 2 months, but acid water samples showed a higher percentage of decayed marrons. Finally, it is possible to define some technological parameters. The immersion time of marrons in water must be at least 5 and no longer than 7 d, in order to avoid cell destruction. A water/marron ratio of 1:1 is advised. Using acid water, the samples with the ratios of 1:2 and 1:1 showed higher polyphenol and sugar contents. However, the metabolic response of these marrons was assumed to be a “stress response” to acid water. 相似文献
993.
Andrea Maiorano Amedeo Reyneri Aronne Magni Cesare Ramponi 《Agricultural Systems》2009,102(1-3):17-23
Fumonisins constitute a group of carcinogenic metabolites produced mainly by Fusarium verticillioides, the most common fungi associated with maize grain. The limits fixed for fumonisins in maize for food and feed by the European Union (EU) could represent a serious problem for maize areas in the south of Europe where F. verticillioides encounters extremely favourable meteorological and environmental conditions for its life cycle. Prevention strategies through pre-harvest agronomic management can achieve the quality and safety standards required by EU regulations.On the basis of results from agronomic field trials conducted in the North of Italy, the first version of an agronomic decision tool has been created to help farmers, collectors and processors manage fumonisin contamination in order to respect the EU fumonisin limits and the constraints required by a given market outlet. The tool is based on the concept of agronomic exposure to fumonisin risk (AEFR), which is a qualitative evaluation of the impact that a crop management system can have on fumonisin contamination.The validation has shown the validity of the decision tool, which was able to correctly classify the crop management systems of real farms according to their agronomic exposure to fumonisin risk: increasing levels of fumonisin contamination corresponded to increasing AEFR levels. 相似文献
994.
Effect of several organic manures on the efficiency of Azospirillum lipoferum
Under greenhouse conditions, it was examined how grass mulch, farmyard manure and compost influence the efficiency of Azospirillum lipoferum with Sorghum bicolor. The organic manures were added at 5 concentrations: 0, 50, 100, 200 and 300 dt/ha.
With the exception of the highest amount the grass mulch always induced a good effect of Azospirillum on plant yield and nutrient uptake. The application of farmyard manure or compost did not improve the growth of the inoculated plants. With farmyard manure the inoculation even lowered shoot dry weights. But in both treatments the inoculated plants showed considerably increased N and P contents. In addition to the N2 fixation the inoculation with Azospirillum lipoferum apparently can increase the capacity of the sorghum plant roots to absorb P. Primarily, the organic manures create better growing conditions for the bacteria and simultaneously serve as P sources. 相似文献
Under greenhouse conditions, it was examined how grass mulch, farmyard manure and compost influence the efficiency of Azospirillum lipoferum with Sorghum bicolor. The organic manures were added at 5 concentrations: 0, 50, 100, 200 and 300 dt/ha.
With the exception of the highest amount the grass mulch always induced a good effect of Azospirillum on plant yield and nutrient uptake. The application of farmyard manure or compost did not improve the growth of the inoculated plants. With farmyard manure the inoculation even lowered shoot dry weights. But in both treatments the inoculated plants showed considerably increased N and P contents. In addition to the N
995.
In 69 dairy and beef herds in the district of Kamenz, Saxony, with a total number of 21,783 and 89.6% of the district's cattle, a voluntary BVDV eradication protocol was implemented from 2000 to 2007. The aim was to achieve eradication as comprehensive as possible and to prepare the herds for the mandatory eradication program. Essential preconditions for the accreditation of a herd as "free of BVD virus" were the antigen test of all cattle and their offspring for 12 months including completeness check and a negative serological random sampling of young cattle. Mean eradication period of infected herds lasted 45.6 months, herd size, and the number of newly purchased cattle were found to have a significant influence. In five infected farms calf losses significantly decreased after termination of the eradication. further examination of the 126 antigen test positive animals from 15 herds resulted in 87 persistently infected (PI) and 15 transiently infected (TI) individuals, 24 animals missed the second test. Furthermore, out of the 87 PI's 30 individuals (34%) had antibodies against BVDV. Eight farms vaccinated their whole herd, seven only the young stock before first breeding, and 54 herds did not vaccinate, respectively. Concluding from this study, the epidemiological particularities of the farms should be taken in account. Testing of all cattle in a minimum of time including, official monitoring of immediate culling of PI's, immediate epidemiological research, and serological monitoring of the eradication process is necessary. 相似文献
996.
997.
Stein VM Puff C Genini S Contioso VB Baumgärtner W Tipold A 《Veterinary immunology and immunopathology》2011,144(1-2):17-26
Matrix metalloproteinases (MMPs), MMP inhibitors (TIMPs, tissue inhibitors of matrix metalloproteinases), and the membrane-anchored glycoprotein RECK (reversion-inducing cysteine-rich protein with Kazal motifs) contribute to the pathogenesis of many CNS diseases. To assess the potential pathogenetic roles of microglial MMP, TIMP, and RECK generation in extracellular matrix breakdown, opening of the blood brain barrier (BBB) and subsequent recruitment of leukocytes in the CNS, twenty-four dogs suffering from spontaneously occurring different intracranial and extracranial (control group) diseases were examined. Microglia cells were isolated ex vivo by density gradient centrifugation and their expressions of MMP-2, MMP-9, MMP-12, MMP-13, MMP-14, TIMP-1, TIMP-2, and RECK were examined via quantitative real-time polymerase chain reaction (qPCR). Zymography on CNS tissues in selected cases was performed to assess differences at the protein level. Dogs were grouped in different disease categories according to histopathological examinations, in groups with or without inflammatory reactions, and in groups with/without contrast enhancement in advanced diagnostic imaging as a function of BBB breakdown. The results showed a significant up-regulation of MMP-9 in dogs with inflammation in the nervous system compared to dogs with non-inflammatory diseases. An increased expression of MMP-9 might lead to a facilitated invasion of white blood cells. Furthermore, down-regulation of MMP-13 was found in dogs with contrast enhancement. Zymographical data reflected MMP-2 qPCR data. In conclusion, differential expression of MMPs and their inhibitors, but not of RECK, which might crucially influence the pathogenesis of a given disease, could be demonstrated in canine microglia. This reflects a further pathway in the microglial repertoire to respond to various disease conditions in the CNS, a characteristic that might be of particular relevance as a target for specific treatments. 相似文献
998.
Traversa D Aste G Di Cesare A Paoletti B Di Tommaso M Di Giulio E Pampurini F Tunesi C Boari A 《Veterinary parasitology》2011,179(1-3):107-112
In the past decade reports of canine subcutaneous dirofilariosis, caused by the mosquito-transmitted nematode Dirofilaria repens, increased in number in several countries in Europe, along with a rise of human cases. Given the merit to the new approaches for the control and treatment of this infection, the present study evaluated the efficacy of a single application of the spot-on formulation containing imidacloprid 10%/moxidectin 2.5% (Advocate(?), Bayer Animal Health) in the elimination of D. repens microfilariaemia in naturally infected dogs. In September 2009, 18 dogs with a natural infection by D. repens were enrolled in the study. In October 2009 all the dogs were treated once with Advocate(?) and the presence/absence of circulating MF and skin lesions after treatment was evaluated monthly until April 2010. From November 2009 to April 2010 15 dogs scored negative for D. repens while one dog remained negative till March 2010 when it died. Two dogs had a recurrence of microfilariaemia in December 2009 and January 2010 respectively. Nine infected dogs showed skin lesions at the beginning of the trial, which disappeared after treatment in 7 dogs, whereas the other two symptomatic dogs did not show any dermatological improvement until the end of the trial even though they scored negative for D. repens microfilariae. This study demonstrated that a single dermal administration of Advocate(?) is effective in eliminating microfilariae of D. repens and likely has a certain degree of activity in killing subcutaneous adult worms as well. This study demonstrates the efficacy of Advocate(?) in the treatment of dermatitis caused by D. repens. Also, these results are of importance towards further control programs aiming to reduce the number of bites infectious for mosquitoes and the risk of infection for both humans and dogs. 相似文献
999.
1000.
Vörös K Seehusen F Hungerbühler S Meyer-Lindenberg A von der Hoeh N 《Journal of the American Animal Hospital Association》2011,47(4):e42-e49
A heart murmur was detected in a 10 mo old, female New Zealand White rabbit. Auscultation revealed cardiac murmurs both at the left and right hemithorax. Phonocardiography confirmed the systolic-diastolic nature of the left-sided and the systolic character of the right-sided murmur. Electrocardiography showed normal sinus rhythm; tall R waves and large T waves in lead II; and deep S waves in leads II, III, and aVF. Thoracic radiography demonstrated generalized cardiomegaly with prominent pulmonary vasculature. Echocardiography revealed a perimembraneous ventricular septal defect with aortic insufficiency. Signs of biventricular volume overload, relative pulmonic stenosis, and pulmonary valve insufficiency were also seen as consequences of the defect. Necropsy demonstrated a ventricular septal defect just below the aortic valve, a dilated pulmonary trunk, dilated and hypertrophied ventricles, dilated atria, and rightward displacement of the aortic root. Cardiac histopathology showed ventricular cardiomyocyte degeneration (swelling and hypereosinophilia of the cytoplasm with a loss of cross striation, and nuclear hyperchromasia), cartilaginous metaplasia of the aorta, and subendocardial fibrosis of the right ventricular flow tract. 相似文献