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91.
Genotype × environment interaction (GEI) affects marketable fruit yield and average fruit weight of both hybrid and open-pollinated
(OP) tomato genotypes. Cultivars vary significantly for marketable fruit yield, with hybrid cultivars having, on average,
higher yield than OP cultivars. However, information is scanty on environmental factors affecting the differential response
of tomato genotypes across environments. Hence, the aim of this research was to use factorial regression (FR) and partial
least squares (PLS) regression, which incorporate external environmental and genotypic covariables directly into the model
for interpreting GEI. In this research, data from an FAO multi-environment trial comprising 15 tomato genotypes (7 hybrid
and 8 OP) evaluated in 18 locations of Latin America and the Caribbean were analyzed using FR and PLS. Environmental factors
such as days to harvest, soil pH, mean temperature (MET), potassium available in the soil, and phosphorus fertilizer accounted
for a sizeable portion of GEI for marketable fruit yield, whereas trimming, irrigation, soil organic matter, and nitrogen
and phosphorus fertilizers were important environmental covariables for explaining GEI of average fruit weight. Locations
with relatively high minimum and mean temperatures favored the marketable fruit yield of OP heat-tolerant lines CL 5915-223
and CL 5915-93. An OP cultivar (Catalina) and a hybrid (Apla) showed average marketable fruit yield across environments, while
two hybrids (Sunny and Luxor) exhibited outstanding marketable fruit yield in high yielding locations (due to lower temperatures
and higher pH) but a sharp yield loss in poor environments. Two stable hybrid genotypes in high yielding environments, Narita
and BHN-39, also showed high and stable yield in average and low yielding environments. 相似文献
92.
Verez-Bencomo V Fernández-Santana V Hardy E Toledo ME Rodríguez MC Heynngnezz L Rodriguez A Baly A Herrera L Izquierdo M Villar A Valdés Y Cosme K Deler ML Montane M Garcia E Ramos A Aguilar A Medina E Toraño G Sosa I Hernandez I Martínez R Muzachio A Carmenates A Costa L Cardoso F Campa C Diaz M Roy R 《Science (New York, N.Y.)》2004,305(5683):522-525
Glycoconjugate vaccines provide effective prophylaxis against bacterial infections. To date, however, no commercial vaccine has been available in which the key carbohydrate antigens are produced synthetically. We describe the large-scale synthesis, pharmaceutical development, and clinical evaluation of a conjugate vaccine composed of a synthetic capsular polysaccharide antigen of Haemophilus influenzae type b (Hib). The vaccine was evaluated in clinical trials in Cuba and showed long-term protective antibody titers that compared favorably to licensed products prepared with the Hib polysaccharide extracted from bacteria. This demonstrates that access to synthetic complex carbohydrate-based vaccines is feasible and provides a basis for further development of similar approaches for other human pathogens. 相似文献
93.
Nicolás Astorga Juan Manuel Afonso María Jesús Zamorano Daniel Montero Víctor Oliva Hipólito Fernández & María Soledad Izquierdo 《Aquaculture Research》2005,36(8):733-738
The use of the fluorescent visible implant elastomer (VIE) tagging system in juvenile gilthead seabream, Sparus auratus L., between 7 and 18 g was examined. Four different colours (red, green, orange and yellow), three body positions (dorsal, lateral and caudal) and two orientations (horizontal and vertical) were tested. The mean tag application time for each fish was 15.7±0.32 s. There was no mortality associated with the method of tagging. The most visible tag colour was red. Injection orientation had a significant effect on length, width, fragmentation and fluorescent intensity of the tag. Horizontal tagging is recommended because of high fluorescent intensity, low fragmentation and for double tagging. There were no differences in growth between untagged controls and the VIE‐tagged fish. 相似文献
94.
Sol Ortiz-García Mariano Torres-Gómez Adalberto Benavides Manuel Anaya Marisol Anglés-Hernández Areli Cerón Helena Cotler José A. Cueto-Wong Jorge D. Etchevers Fabián Fernández-Luqueño Jorge Gonzalez-Meraz Armando Guerrero-Peña Marco Meneses María Miranda Mario Pérez Leonardo Pulido Laura Bertha Reyes-Sánchez Verónica Reynoso Vinisa Saynes Víctor M. Villalobos-Arámbula Blanca Prado Mario Guevara 《European Journal of Soil Science》2023,74(5):e13395
The National Soil Strategy for Sustainable Agriculture (ENASAS) arises in response to the increasing need to organize, coordinate and strengthen the implementation of actions oriented to the sustainable management of Mexico's agricultural soils. The measures recommended in this paper allow the conservation and maintenance of soils' essential functions for agriculture, food security and population well-being. The health and quality of agricultural soils are under constant pressure from several factors, mainly anthropogenic. One of ENASAS's objectives is to identify and stop the causes involved in land degradation processes using a systemic approach. From this perspective, the participation of various actors in sustainable soil management allows the integration of different systems, practices, techniques and knowledge that promotes awareness among the entire population about the importance of soil resources. On the other hand, given current limitations on the availability of information necessary to support decision-making and evaluate the result of the actions implemented, ENASAS promotes the generation of tools that provide reliable and updated data regarding Mexico's agricultural soils. In the same sense, this strategy encourages the development of scientific and technological research and the transfer of knowledge that meets the needs of farmers, particularly those who carry out their activities on a smaller scale. This perspective describes ENASAS as a multi-institutional initiative that will support sustainable soil management practices across the country's agricultural systems of Mexico and contribute to the adaptation and mitigation of global environmental change. 相似文献
95.
J Quinteiro R Vidal M Izquierdo C G Sotelo M J Chapela R I Pérez-Martín H Rehbein G L Hold V J Russell S E Pryde C Rosa A T Santos M Rey-Méndez 《Journal of agricultural and food chemistry》2001,49(11):5108-5114
The use of DNA-based methodologies in identification of hake species belonging to the Merluccius genus was shown to be successful. A short fragment of the left hypervariable domain of the mitochondrial control region was amplified, sequenced, and digested from 11 hake species. The hake-specific PCR product, due to its limited size, was obtained in a variety of tissue samples with different levels of DNA concentration and degradation, including sterilized food products. On the basis of this phylogenetically informative 156-bp sequence were selected four restriction enzymes (ApoI, DdeI, DraIII, and MboII) that allow the hake species discrimination. Species identification by phylogenetic analysis of sequences or by PCR-RFLP methodologies is useful in a variety of scenarios including authentication of thermally processed food, detection of food components, and species determination of individuals whose morphological characters are removed. 相似文献
96.
Cuphea (Cuphea viscosissima Jacq. × C. lanceolata W.T. Aiton; PSR23) is a potential new oilseed crop. Its oil is high in medium-chain fatty acids that are suitable for detergent/cleaner applications and also for cosmetics. The objective of this study was to determine the critical temperatures for cuphea seed germination. To determine the base, maximum, and optimum temperatures for seed germination, mature cuphea seeds were harvested from plants grown at Prosper, ND, in 2004, 2005, and 2006. Seeds were germinated on a temperature-gradient bar varying between 5 and 35 °C. Cumulative germination was calculated for each temperature treatment. Base temperature (Tb) and optimum temperature (To) were estimated from the third-order polynomial temperature-response functions for each year. In addition, germination rate per day was used in a linear model to estimate the base temperature below which germination rate was equal to zero (Tb), and the maximum temperature above which germination was equal to zero (Tm). The optimum temperature (To) was calculated as the intercept of sub-optimal and supra-optimal temperature-response functions. Through the third-order polynomial temperature-response functions and the sub-optimal/super-optimal intercept approaches, we were able to generate six estimates for each critical value. Estimates of the base temperature for cuphea seed germination ranged between 3.3 and 11 °C, with the most reliable estimates between 6 and 10 °C, similar to many warm-season crops such as corn (Zea mays L.) and sorghum (Sorghum bicolor L.). The optimum temperature for cuphea seed germination ranged between 18.5 and 24 °C with a mean value of 21 °C. The maximum temperature for seed germination ranged 33–38 °C. On this basis, a cuphea planting date after 20 May is recommended for east-central North Dakota. 相似文献
97.
Quantification of total bacteria, enterobacteria and lactobacilli populations in pig digesta by real-time PCR 总被引:2,自引:0,他引:2
Castillo M Martín-Orúe SM Manzanilla EG Badiola I Martín M Gasa J 《Veterinary microbiology》2006,114(1-2):165-170
Jejunum digesta samples were taken from weaning pigs in order to evaluate real-time PCR (qPCR) as a method for quantifying pig gut bacteria. Total bacteria, lactobacilli and enterobacteria were quantified by qPCR and the results were compared with those obtained with traditional methods: 4',6-diamidino-2-phenylindole (DAPI staining) for total bacteria, selective culture for lactobacilli and enterobacteria. Real-time PCR showed higher values in terms of 16S rRNA gene copies than DAPI counts or CFU. Despite the differences, the lactobacilli:enterobacteria ratio was similar between methods (2.5 +/- 0.58 for qPCR and 3.1 +/- 0.71 for selective culture, P = 0.39). Possible reasons for the higher PCR counts are discussed considering both an overestimation with PCR by quantification of dead bacteria or free DNA and also an underestimation with conventional methods. Inherent differences in the pre-treatment of the samples could partially explain the discrepancies observed. Regardless of the numerical differences between methods, values obtained by qPCR and traditional methods showed a significant correlation for lactobacilli and total bacteria. In the light of these results, real-time PCR seems a valid method to quantify microbial shifts in the gastrointestinal tract. 相似文献
98.
Ferreres F Ribeiro V Izquierdo AG Rodrigues MA Seabra RM Andrade PB Valentão P 《Journal of agricultural and food chemistry》2006,54(16):5782-5789
The phenolic compounds of Rumex induratus leaves were determined by HPLC-DAD-MS/MS-ESI. The results revealed a profile composed of 19 compounds: caffeoyl-hexoside, two p-coumaroyl-hexoside isomers, feruloyl-hexoside, sinapoyl-hexoside, 6-C-hexosyl-quercetin, 8-C-hexosyl-luteolin, 6-C-hexosyl-luteolin, 6-C-hexosyl-apigenin, 3-O-hexosyl-quercetin, 3-O-rutinosyl-quercetin, 7-O-hexosyl-diosmetin, 3-O-rutinosyl-isorhamnetin, 7-O-(acetyl)-pento-hexosyl-diosmetin, 6-C-hexosyl-genkwanin, and four unidentified O-glycosyl-C-glycosylflavones. The quantification of the identified phenolics by HPLC-DAD showed 6-C-hexosyl-luteolin as the main compound. Organic acid composition was determined by HPLC-UV, revealing a high content of oxalic acid. R. induratus was also investigated for its capacity to act as a scavenger of DPPH and superoxide radicals. Good antioxidative results were obtained against both radicals. Unlike other species of the genus Rumex, R. induratus did not present any anthraquinone derivative. 相似文献
99.
Quantification of regulating ecosystem services provided by weeds in annual cropping systems using a systematic map approach 下载免费PDF全文
C Blaix A C Moonen D F Dostatny J Izquierdo J Le Corff J Morrison C Von Redwitz M Schumacher P R Westerman 《Weed Research》2018,58(3):151-164
Ecosystem services have received increasing attention in life sciences, but only a limited amount of quantitative data are available concerning the ability of weeds to provide these services. Following an expert focus group on this topic, a systematic search for articles displaying evidence of weeds providing regulating ecosystem services was performed, resulting in 129 articles. The most common service found was pest control and the prevailing mechanism was that weeds provide a suitable habitat for natural enemies. Other articles showed that weeds improved soil nutrient content, soil physical properties and crop pollinator abundance. Weeds were found to provide some important ecosystem services for agriculture, but only a small number of studies presented data on crop yield. Experimental approaches are proposed that can: (i) disentangle the benefits obtained from ecosystem services provisioning from the costs due to weed competition and (ii) quantify the contribution of diverse weed communities in reducing crop competition and in providing ecosystem services. Existing vegetation databases can be used to select weed species with functional traits facilitating ecosystem service provisioning while having a lower competitive capacity. However, for services such as pest control, there are hardly any specific plant traits that have been identified and more fundamental research is needed. 相似文献
100.
True digestibility of lysine (LYS) in crystalline L-LYS.HCl and casein determined in cecectomized adult roosters was not significantly different from 100%. Subsequent 9-d growth assays were conducted to determine the bioavailability of LYS in casein, in L-LYS.HCl, and in a mixture of crystalline amino acids simulating casein's amino acid profile. Based on slope-ratio methodology, LYS bioavailability relative to casein was estimated to be 101.4 and 99.9% in L-LYS.HCl and in the casein-simulated amino acid mixture, respectively. Procedures also were developed for assessment of LYS bioavailability in crystalline L-LYS.HCl by comparing growth responses to intraperitoneally injected (IP-LYS) and crop-intubated LYS (CI-LYS) in chicks fed LYS-deficient corn-sesame meal diets. Graded increments of pH-adjusted L-LYS.HCl were administered twice daily in .5-ml doses during the course of 8-d growth assays. Chicks receiving CI-LYS also received .5 ml of IP saline at each dosing, and those receiving IP-LYS also received CI saline at each dosing. Slope-ratio multiple linear regression of gain (g) regressed on LYS administered (mg) was assessed for both ad libitum-fed and meal-fed chicks. Linear growth responses to LYS were obtained with both routes of administration and in both feeding regimens. The CI-LYS slopes ranged from 103 to 125% of those obtained with IP-LYS administration. These results support the view that crystalline L-LYS.HCl is 100% digestible and bioavailable. 相似文献