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51.
M. I. Siri P. Villanueva M. J. Pianzzola L. Franco Fraguas G. Galván M. Acosta F. Ferreira 《Potato Research》2004,47(3-4):127-138
Summary The in vitro antimicrobial activity of extracts from accessions ofSolanum commersonii Dun. collected in the south of Uruguay was investigated against five microorganisms including the pathogenRalstonia solanacearum. A total of 30 extracts corresponding to organic and aqueous extracts were studied. Interestingly, most of the positive results
for growth inhibition were againstR. solanacearum. The extracts were also analyzed for the presence of glycoalkaloids and lectins. Six of the ten aqueous extracts showed lectin
presence and a wide variation in the type and amounts of glycoalkaloids, was found. Results indicate that there is no clear
relationship between the antimicrobial activity against the five microorganisms screened and the presence or amounts of lectins
and glycoalkaloids, traditionally regarded as possible antimicrobial metabolites in theSolanum genus, which indicates the presence of as yet unidentified antimicrobial compounds. 相似文献
52.
Sánchez-Quezada Vanessa Campos-Vega Rocio Loarca-Piña Guadalupe 《Plant foods for human nutrition (Dordrecht, Netherlands)》2021,76(3):311-318
Plant Foods for Human Nutrition - Vegetal wastes are currently a source of pollution due to the excess of organic compounds in the environment. Seeds are the main by-product of the avocado industry... 相似文献
53.
Eustolia Rodríguez-Muñoz Gilberto Herrera-Ruiz Gustavo Pedraza-Aboytes Guadalupe Loarca-Piña 《Plant foods for human nutrition (Dordrecht, Netherlands)》2009,64(1):46-51
Natural oleoresins rich in lycopene were obtained from two varieties of tomato (Zedona and Gironda) and their nutraceutical
potential (antioxidant and antimutagenic capacity) was evaluated. Both oleoresins had a high content of lycopene, 58.33 ± 1.67 mg/g
(Zedona) and 63.97 ± 0.80 mg/g (Gironda). The antioxidant activity (AA) of the oleoresins by β-carotene method were 56.4–74.5%
(Zedona) and 51–72.8% (Gironda), while when using the free radical stable 2,2-diphenyl-picryl-hydrazyl (DPPH) method, the
antiradical activity (ARA) was determined to be 18.2–32.7% (Zedona) and 16.6–26.7% (Gironda) for the concentrations tested
that of 200–400 μM equivalents of lycopene. The antimutagenic activity of the oleoresins was tested against aflatoxin B1 (AFB1) using the microsuspension assay, both varieties had a very high antimutagenic potential against AFB1 (60–66%).These results suggest the NCRT can be taken advantage to obtaining rich oleoresin in lycopene with a nutraceutical
value. 相似文献
54.
Aparicio-Fernández X Reynoso-Camacho R Castaño-Tostado E García-Gasca T González de Mejía E Guzmán-Maldonado SH Elizondo G Yousef GG Lila MA Loarca-Pina G 《Plant foods for human nutrition (Dordrecht, Netherlands)》2008,63(1):35-40
Jamapa bean is a black Phaseolus vulgaris variety rich in condensed tannins, anthocyanins and flavonols with interesting biological activities. The objective of this
work was to evaluate the antiradical capacity (ARC) of a Jamapa bean methanolic extract (BME) and some of the proanthocyanidin-rich
fractions derived from it, using the 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay. The effect of the BME on some proteins involved
in apoptosis on HeLa cells was also evaluated. A strong correlation between proanthocyanidin concentration in BME and antiradical
capacity was found, suggesting that these compounds contribute significantly to antiradical activity. BME was a better radical
scavenger than butylated hydroxytoluene (45.6 and 33.9% ARC at 400 μM, respectively). Two proanthocyanidin-rich fractions
obtained after a preliminary separation of the BME using Toyopearl (TP4 and TP6) exhibited a higher antiradical activity than
the parent extract. The treatment of HeLa cells with 35 μg BME/ml/24 h increased the expression of Bax and Caspase-3, pro-apoptotic
proteins (6.13 and 1.2 times for Caspase-3 and Bax, respectively). The mechanism of action of some proteins involved in apoptosis
was also evaluated, and the results suggest that black Jamapa bean could be an important source of polyphenolic compounds
with potential biological use as antioxidant and anticancer agents. 相似文献
55.
Martínez-Rocha A Puga R Hernández-Sandoval L Loarca-Piña G Mendoza S 《Plant foods for human nutrition (Dordrecht, Netherlands)》2008,63(1):1-5
Free essential oil methanolic extracts from three different geographical populations of Lippia graveolens in México were screened for antioxidant and antimutagenic properties by the DPPH and Kado microsuspension assay, respectively.
Total phenolic and flavonoid contents as well as HPLC identification and quantification of naringenin and rosmarinic acid
were also carried out. In addition, a taxonomical phenetic analysis was performed. The L. graveolens extracts showed varying content of phenols and flavonoids. Significant concentration of rosmarinic acid was found for the
first time in the species. All the extracts were capable of scavenging DPPH radicals in a concentration dependent fashion;
the IC50 values correlate with the phenolic content. None of the extracts was toxic to TA100 and TA98 strains at the concentrations
tested; moreover, the extracts at a concentration equivalent to 200 μg of gallic acid inhibited a 39 and 30% the mutagenicity
induced by 4-nitro-o-phenylenediamine and sodium azide, respectively. The results suggest that the Mexican oregano is a source of polar bioactive
ingredients for the food industry. 相似文献
56.
Guadalupe Méndez-Montealvo Francisco J. García-Suárez Octavio Paredes-López Luis A. Bello-Pérez 《Journal of Cereal Science》2008
Nixtamalization of maize grain is an ancient process that until now is used for tortilla production. This thermal-alkaline process produces important changes in morphology and rheological characteristics of starch that is the major component of maize. The aim of this study was to evaluate changes in the morphological and rheological properties of starch brought by nixtamalization of maize using image analysis and dynamic rheometry, respectively. Nixtamalized maize starch (NS) presented granule sizes higher than starch isolated from raw maize (S) due to the partial swelling produced in the nixtamalization process. In dynamic tests during the retrogradation kinetics, an inverse effect of the temperature was observed in the re-arrangement of starch components. NS was affected due to the thermal-alkaline process presenting an annealing that provoked a reduction in its ability to develop gels. This information is important during the processing of nixtamalized maize to masa and tortilla production. 相似文献
57.
J P Hoover A E Castro M A Nieves 《Journal of the American Veterinary Medical Association》1985,187(11):1162-1165
The Oklahoma Department of Wildlife Conservation acquired 20 American river otters (Lutra canadensis) between 1984 and 1985 for reintroduction into Oklahoma waterways. In 1985, 10 otters were evaluated for serum antibody titers after vaccination with canine distemper virus, canine adenovirus type 2, canine parvovirus (CPV), feline panleukopenia virus (FPV), feline rhinotracheitis virus (FRV), and feline calicivirus. Prevaccination serum-virus neutralization (SVN) antibody to feline rhinotracheitis virus was found in 2 otters and to feline calicivirus in 1 otter. Using an indirect fluorescent antibody (IFA) assay, prevaccination antibody to CPV and FPV was found in 2 otters. A significant increase in SVN antibody titers was found after vaccination of otters with canine adenovirus type 2 (6 of 8 animals) and feline calicivirus (1 of 8 animals). One of 8 otters developed significant antibody titers to CPV and FPV, as measured by IFA assay. Otters did not develop SVN antibody titers to canine distemper virus after vaccination. Antigens of feline leukemia virus, using ELISA, or antibodies to feline infectious peritonitis, using IFA assay, were not found in the 20 otters. 相似文献
58.
Saavedra-Jiménez Luis Antonio Ramírez-Valverde Rodolfo Núñez-Domínguez Rafael Ruíz-Flores Agustín García-Muñiz José Guadalupe 《Tropical animal health and production》2019,51(8):2235-2241
Tropical Animal Health and Production - Nitrogen plays an important role in the metabolism of living organisms due to the variety of physiological functions that involve molecules that contain it.... 相似文献
59.
Evaluation of a fibrate,specific stimulant of PPARα, as a therapeutic alternative to the treatment of clinical ovine pregnancy toxaemia 下载免费PDF全文
S. Da Silva L. G. Cal‐Pereyra A. Benech J. Acosta‐Dibarrat M. J. Martin M. C. Abreu S. Perini J. R. González‐Montaña 《Journal of veterinary pharmacology and therapeutics》2016,39(5):497-503
Ovine pregnancy toxaemia is a metabolic disorder affecting sheep in their last 6 weeks of pregnancy as a result of their inability to maintain adequate energy homoeostasis. Different alternative treatments are available with variable results. The aim of this research was to evaluate a peroxisome proliferator‐activated receptor alpha (PPARα) stimulant as an alternative to treat clinical pregnancy toxaemia. Thirty‐three adult sheep, with known gestation date and carrying a single foetus, were fasted from day 130 of gestation until animals showed clinical disease. From that moment onwards, sheep were treated during 6 days with three different therapeutic alternatives: 10 mg/kg of 2‐methyl‐2‐phenoxy‐propionic acid; 10 mg/kg of 2‐methyl‐2‐phenoxy‐propionic acid + 100 mL of propylene glycol oral; or 100 mL of propylene glycol oral. Glycaemia and serum β‐hydroxybutyrate (BHOB) were determined daily. Liver biopsies were taken at day 130 of gestation, at the beginning and end of treatments and at 5 days postpartum, evaluating the extent and degree of the steatosis lesion. Even though in sheep treated with 2‐methyl‐2‐phenoxy‐propionic acid, serum concentrations of glucose and BHOB recovered more slowly, we conclude that 2‐methyl‐2‐phenoxy‐propionic acid alone or combined with propylene glycol can be used as an alternative to effectively treat fatty liver, and therefore pregnancy toxaemia. 相似文献
60.
Laura Guadalupe Grtter Luciano Cattaneo Patricia Estela Marini Michael E. Kjelland Luis B. Ferr 《Reproduction in domestic animals》2019,54(4):655-665
Sperm cryopreservation facilitates the storage and transport of germplasm for its use in artificial insemination (AI) and other advanced reproductive technologies. The cryopreservation process can damage sperm and compromise functionality. Several cryobiological studies have found that the physical and biological factors that affect sperm survival at low temperatures during the cryopreservation process often involve the integrity of sperm membrane. In this review, the behaviour of the sperm membrane against cooling, cold shock, ice crystal formation, oxidative stress, osmotic changes, reorganization of the lipid bilayer and addition of cryoprotective agents (CPA) is discussed. In addition, the phenomenon of reactive oxygen species (ROS) and its relationship with the cryopreservation process is also described. Semen cryopreservation techniques have progressed slowly in past years, and the current performance, measured as post‐thawed survival, is not very different compared to past decades. Recent advances in understanding the structure of the cell membrane, its function and metabolism have driven to new conservation systems, including lyophilization and vitrification. However, none of these technologies is commercially available, although its future appears very promising. 相似文献