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151.
Rogers CS Stoltz DA Meyerholz DK Ostedgaard LS Rokhlina T Taft PJ Rogan MP Pezzulo AA Karp PH Itani OA Kabel AC Wohlford-Lenane CL Davis GJ Hanfland RA Smith TL Samuel M Wax D Murphy CN Rieke A Whitworth K Uc A Starner TD Brogden KA Shilyansky J McCray PB Zabner J Prather RS Welsh MJ 《Science (New York, N.Y.)》2008,321(5897):1837-1841
Almost two decades after CFTR was identified as the gene responsible for cystic fibrosis (CF), we still lack answers to many questions about the pathogenesis of the disease, and it remains incurable. Mice with a disrupted CFTR gene have greatly facilitated CF studies, but the mutant mice do not develop the characteristic manifestations of human CF, including abnormalities of the pancreas, lung, intestine, liver, and other organs. Because pigs share many anatomical and physiological features with humans, we generated pigs with a targeted disruption of both CFTR alleles. Newborn pigs lacking CFTR exhibited defective chloride transport and developed meconium ileus, exocrine pancreatic destruction, and focal biliary cirrhosis, replicating abnormalities seen in newborn humans with CF. The pig model may provide opportunities to address persistent questions about CF pathogenesis and accelerate discovery of strategies for prevention and treatment. 相似文献
152.
Mohamed Abdel-Rahim Omar Bahattab Fatma Nossir Yahya Al-Awthan Riad H. Khalil Radi Mohamed 《Marine drugs》2021,19(3)
This study was aimed to evaluate the efficiency of Sargassum polycystum and nucleotides- supplemented diets to improve immune response and cold-tolerance of juvenile Litopenaeus vannamei. Four treatments were evaluated: T1, the control, shrimp received only a basal diet; T2, a basal diet with 500 ppm nucleotides; T3, a basal diet with 500 ppm S. polycystum powdered; T4, a basal diet with 500 ppm nucleotides and 500 ppm S. polycystum powdered. Shrimp were fed experimental diets for 56 days. Results revealed shrimp fed T4 diet exhibited the best significant improvement in water quality, survival, growth, and feed utilization indices followed by T2, and T3, while T1 showed the worst values. Additionally, nonspecific immune responses (phagocytosis (%), lysozyme, phenoloxidase, super oxide dismutase (SOD) activity, total nitric oxide) were improved with 1.7–3.2-fold in T4 higher than T1. Histomorphology of hepatopancreas in T4 showed the most increased activation of the hepatic glandular duct system compared with the other treatments. Moreover, nucleotides/seaweed-supplemented diets upregulated relative expression of cMnSOD, Penaeidin4, and heat shock protein70 (HSP70) genes, while translationally controlled tumor protein (TCTP) was downregulated. In conclusion, the synergistic effects of both S. polycystum and nucleotides have many advantages as a growth promoter, immunostimulant, antimicrobial, and cold-tolerant stimulant to L. vannamei. 相似文献
153.
Xiaomin Zhou Omar A. Abdin Bruce E. Coulman Daniel C. Cloutier Mohamed A. Faris Donald L. Smith 《Journal of plant nutrition》2013,36(5):605-616
Plant senescence studies have indicated that internal competition for nutrients such as carbon (C) and nitrogen (N) can be an important factor in the initiation of senescence. A greenhouse experiment was conducted to determine the effect of increased supplies of C and N on senescence of soybean (Glycine max [L.] Merr) plants. Soybean plants were injected with solutions of sucrose (150gL‐1), N (15 mM N), and distilled water from the onset of flowering until senescence using a modified stem injection technique. The average uptake rate of all solutions was 1.3 mL d‐1 per plant. The plants injected with sucrose accumulated the most biomass, followed by those injected with N and distilled water. Soybean plants injected with sucrose senesced 17 days later than the distilled water control while senescence was not delayed for plants injected with N. Injection of either N or sucrose increased the concentration and content of N in soybean plants. The results indicated that intra‐plant‐competition for reduced C plays an important role in plant senescence. Because the total amount of N injected was only 2% of the total plant N, as compared to 31 % for C, the role of intra‐plant competition for N was less clear. 相似文献
154.
Salinas Villafane Omar Roberto Igarashi Toshifumi Kurosawa Mitsuru Takase Toshio 《Water, air, and soil pollution》2013,224(3):1-12
In this study, we investigate the corrosion effects on modern materials at various sheltered and unsheltered locations in the Greater Athens Area (GAA) due to atmospheric pollution, since materials deterioration could emerge severe economic costs in the near future. The preselected materials are weathering steel, copper, bronze, zinc, and aluminum, which are mainly used in modern constructions in the GAA. The method applied in this study leads in the production of corrosion maps for GAA in the period 2000–2009 by using sophisticated geoanalytical methods together with dose–response functions for the selected materials. The corrosion effects are significant for weathering steel, moderate for copper and bronze and weak for zinc and aluminum. Also, a corrosion trend analysis is performed, which can be a very helpful tool for future protection of such materials from atmospheric pollution. The results show increasing corrosion trends for weathering steel and copper in the eastern regions of GAA, probably caused by the recent operation of the Athens International Airport at Spata, while no corrosion trends were observed to the other materials. The method applied in this work provides comprehensive results for the estimation of the impact of atmospheric corrosion on various construction materials. 相似文献
155.
156.
Victalina Arredondo-Ruiz Rafael Macedo-Barragán Jaime Molina-Cárdenas Julio Magaña-Álvarez Omar Prado-Rebolledo Luis J. García-Márquez Alejandra Herrera-Corredor Héctor Lee-Rangel 《Tropical animal health and production》2013,45(4):895-900
A study was conducted with the objective to characterize the morphology of Pelibuey sheep in the state of Colima, Mexico. A total of 386 sheep were scored for 12 body measurements in addition to live weight and five racial and eight functional indices were calculated. The influence of sex on the body measurements and indices was analyzed, and morphological harmony was determined through Pearson correlation. The sexual dimorphism was 1.21, with males being 67 % heavier than females. Females and males had a high and moderate degree of harmony in their morphological model, respectively. Pelibuey sheep were dolichocephalous, tended to be medium- to large-sized according to the thoracic index, with a convex curve rump; they were a homogeneous breed, well adapted to environmental and production conditions of the state of Colima, Mexico, and show an undefined zootechnical aptitude and therefore a great potential to be oriented towards meat or milk production through genetic selection or terminal crossbreeding systems using specialized breeds. 相似文献
157.
Faith A. Burden Nicole Du Toit Mariano Hernandez-Gil Omar Prado-Ortiz Andrew F. Trawford 《Tropical animal health and production》2010,42(4):597-605
The examination of 216 donkeys presented for treatment at the Donkey Sanctuary–World Horse Welfare–Universidad Nacional Autonoma
de Mexico mobile clinics revealed a number of health and welfare problems. A general overview of the donkeys’ health was made
and showed that the median body condition score (BCS) in this population was 2.5. Underweight animals only accounted for 26%
of the population. Females, 0–5-year-olds and >21-year-olds, were more likely to be underweight. When analysed, there was
no correlation between faecal worm egg count (FEC) and BCS. The prevalence of strongyle infection as assessed by FEC was shown
to be 80% with a median FEC of 600 eggs per gramme. Donkeys were assessed for body lesions and showed a high prevalence (71%),
particularly in the facial region (54%). Analysis showed that mature animals (6–15 years old) were at increased risk of body
lesions compared to older animals (16+ years old) as were donkeys with dental disease and those in particular villages. Risk
factor analysis for lesions of the face showed that stallions and geldings are at increased risk as were donkeys wearing halters
made from nylon rope. This study has identified areas for further investigation and potential areas where targeted interventions
may be made to improve the health and welfare of working donkeys in Mexico. 相似文献
158.
Omar F. El‐Gayar 《Aquaculture Economics & Management (Blackwell Science)》2013,17(1-2):109-128
Abstract The recent advances in information technology (IT) have had profound impacts on all walks of life and aquaculture is no exception. The growing importance of aquaculture as an alternative source of protein has further emphasized the need to adapt and develop advanced IT for the better management of aquaculture facilities as well as the regional planning for aquaculture development. It is the objective of this paper to review the use and potential prospects of IT in aquaculture management. The information technologies considered are instrumentation and process control, data management, computerized models, decision support systems, artificial intelligence and expert systems, image processing and pattern recognition, geographical information systems, and information centres and networks. The review includes a brief introduction of each of the aforementioned technologies, followed by a survey of their current application as well as their potential use in aquaculture management. 相似文献
159.
160.
Macedo RJ Arredondo V García F Aguilar M Prado O Rodríguez R 《Tropical animal health and production》2012,44(2):349-354
The effects of supplemental yeast culture, litter size, stage and number of lactation on milk composition were studied in
Pelibuey ewes. Twenty ewes were randomly assigned to one of two dietary treatments. Ten control ewes grazed on guinea grass
(Panicum maximum) and were supplemented with concentrate. A further ten ewes received the same diet with 14 g/head/day of yeast culture (Saccharomyces cerevisiae). Colostrum was collected within 24 h after parturition, and subsequently, milk samples were collected at fortnightly intervals
(7, 21, 35, and 49 days). Total solids content averaged 32% in colostrum and 12.5% in milk. Colostrum of primiparous ewes
had higher total solids content than that of ewes with more than five lactations. However, ewes with more than five lactations
produced milk with higher net energy, total solids, protein, and casein than ewes with fewer lactations. Milk at 7 days had
a significantly higher content of energy, total solids, and fat than milk at 21, 35, and 49 days. Total solids content was
lower for ewes rearing one lamb than larger litter sizes. Supplementation with yeast culture did not affect the composition
of colostrum and milk, which was mainly affected by the stage and number of lactation. 相似文献