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61.
Breadmaking is a complex process that involves a series of parameters that must be controlled. Rheological measurements are often used to predict the behavior of wheat dough during processing and the quality of the final product. There are many different dietary fiber sources that can be used to enhance the nutritional quality of bread. However, they will affect processing and final product quality. Response surface methodology (RSM) was employed to study the effects of adding different dietary fiber sources (wheat bran, resistant starch, and locust bean gum) on farinographic parameters of wheat flour. The experiments were conducted according to a 23 central composite rotational design (CCRD). With the experimental results or responses (farinographic parameters), the effect of each variable was calculated and the interactions between them were determined. Models that explain the effects of the different fiber sources on water absorption, arrival time, dough development time, and mixing tolerance index of wheat flour were established. The fiber sources interacted for some of the parameters analyzed, demonstrating that if two or more sources of dietary fiber are present in the mix, they might act different to what would be expected of the sum of them. It was also noticed that for most parameters, wheat bran and locust bean gum had a greater influence on farinographic parameters than resistant starch. The simultaneous presence of the three fibers, within the ranges studied, contributed to an increase in water absorption, arrival time, and mixing tolerance index, and to a reduction in departure time and dough stability.  相似文献   
62.
Soybean contains constituents that have antinutritional and bioactive properties. Enzymatic hydrolysis and germination can enhance the biological activity of these compounds in soybean. The objective of this study was to investigate the effect of germination, Alcalase (protease) hydrolysis, and their combination on the concentrations of antinutritional and bioactive compounds in Brazilian soybean cultivar BRS 133. A combination of germination and Alcalase hydrolysis resulted in the degradation of Bowman-Birk inhibitor (BBI), Kunitz trypsin inhibitor (KTI), and lunasin by 96.9, 97.8, and 38.4%. Lectin was not affected by any of the processing treatments when compared to nongerminated and nonhydrolyzed soy protein extract. Total isoflavones (ISF) and total saponins (SAP) increased by 16.2 and 28.7%, respectively, after 18 h of germination, while Alcalase hydrolysis led to the reduction of these compounds. A significant correlation was found between concentrations of BBI and KTI, BBI and lunasin, BBI and ISF, KTI and lunasin, KTI and ISF, KTI and SAP, lunasin and ISF, and ISF and SAP. Germination and Alcalase hydrolysis interacted in reducing BBI, ISF, and SAP. This study presents a process of preparing soy flour ingredients with lower concentrations of antinutritional factors and with biologically active constituents, important for the promotion of health associated with soybean consumption. In conclusion, 18 h of germination and 3 h of Alcalase hydrolysis is recommended for elimination of protease inhibitors, while bioactives are maintained by at least 50% of their original concentrations.  相似文献   
63.
The antioxidant activity of three major polyamine conjugates, N,N'-dicoumaroyl-putrescine (DCP), N-p-coumaroyl-N'-feruloylputrescine (CFP), and N,N'-diferuloyl-putrescine (DFP) isolated from corn bran, and their related hydroxycinnamic acids, p-coumaric acid and ferulic acid, were evaluated by three antioxidant in vitro assay systems, including 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical and superoxide and hydroxyl radicals generated by enzymatic and nonenzymatic reactions. Additionally, five phenolic compounds were evaluated for melanogenesis inhibitory activity using mushroom tyrosinase and B16 melanoma cells. Most of the phenolic compounds significantly scavenged DPPH, superoxide, and hydroxyl radicals in a dose-dependent manner. Particularly, DFP showed potent DPPH (IC50 = 38.46 microM) and superoxide (IC50 = 291.62 microM) radical scavenging activities, while DCP exhibited the strongest hydroxyl radical scavenging activity (IC50 = 120.55 microM). CFP also exerted moderate DPPH, superoxide, and hydroxyl radical scavenging activities. Meanwhile, DCP (IC50 = 181.73 microM) showed potent tyrosinase inhibitory activity toward l-tyrosine as the substrate, whereas DFP (IC50 = 733.64 microM) significantly inhibited melanin synthesis in B16 melanoma cells. These current results indicate that these three polyamine conjugates from corn bran may be useful potential sources of natural antioxidants and skin-whitening agents.  相似文献   
64.
Fast skeletal light meromyosins (LMMs) of white croaker and walleye pollack were prepared in our expression system using Escherichia coli and determined for their polymer-forming ability and thermodynamic properties by using sodium dodecyl sulfate polyacrylamide gel electrophoresis and differential scanning calorimetry (DSC), respectively. White croaker LMM formed dimer by heating at 80 degrees C and showed only a single peak at 32.1 degrees C of temperature transition in DSC. On the other hand, walleye pollack LMM hardly formed polymer and showed four peaks at 27.7, 30.5, 35.8, and 43.9 degrees C. When Cys525 of white croaker LMM was replaced by alanine, this point-mutated LMM showed no change in its DSC profile but formed no dimer upon heating, suggesting a possible role of Cys525 in dimer formation. On the other hand, walleye pollack LMM where Cys491 was substituted by alanine changed its DSC profile, showing four peaks at 27.9, 29.1, 38.4, and 43.9 degrees C. However, this point-mutated LMM formed no dimer upon heating as in the case of native LMM. These results suggest that cysteine residue(s) participates in thermal gel formation of LMM when it locates in a suitable position of the sequence.  相似文献   
65.
This study was designed to isolate bifidobacteria from human intestines that efficiently converts monolinolein, a monoglyceride form of linoleic acid, into conjugated linoleic acid (CLA), as well as to optimize culture conditions for improving CLA production during milk fermentation. Among 150 screened neonatal bifidobacteria, Bifidobacterium breve LMC 520 showed the highest CLA-producing ability and was tested with different types of fat substrates at various concentrations to determine the optimal conditions for CLA production. Monolinolein was tested as a substrate for CLA production. The incubation time optimized for CLA production was 24 h, and CLA production was proportionally increased with monolinolein concentration. The incubation of LMC 520 with commercial starter strains caused minimal reduction in CLA production. Our results demonstrate that the CLA-producing ability of B. breve LMC 520 could offer beneficial effects when utilized as a starter culture for the development of functional dairy products.  相似文献   
66.
Genetic variation and relationships among members of the azuki bean complex (Vigna angularis) including wild (V. angularis var. nipponensis), weedy, and cultivated types (V. angularis var. angularis), V. nakashimae, and rice bean (V. umbellata) from Korea were examined using the Amplified fragment length polymorphism (AFLP) method. AFLP analysis of 50 accessions revealed 333 (72.1%) polymorphic fragments out of 462 fragments amplified using seven primer combinations. The number of polymorphic fragments within each species was 70 in the azuki bean complex and 41 in V. nakashimae, but there was no polymorphism in rice bean. The number of shared fragments among species ranges from 142 between the azuki bean complex and V. nakashimae to 166 between the azuki bean complex and rice bean. Within the azuki bean complex, the range of shared bands was from 231 between cultivated and weedy types to 238 between cultivated and wild types. A dendrogram generated from Jaccard’s similarity matrix was divided into three groups, which correspond to V. nakashimae, azuki bean complex, and rice bean. The relationship between azuki bean and rice bean is closer than between azuki bean and V. nakashimae. Phenetic distances averaged 0.502 between the azuki bean complex and V. nakashimae and 0.467 between the azuki bean complex and rice bean. Within the azuki bean complex, the weedy type was more closely related to wild than cultivated types. But UPGMA dendrogram of the azuki bean complex reveals that each type is not clearly isolated. These results will help to understand genetic diversity and evolutionary dynamics of Vigna in Korea.  相似文献   
67.
Apples are one of the largest contributors of fruit phenolics of all fruits consumed by Americans and contain a variety of bioactive compounds, which have health benefits. Consumption of apples has been linked to reduced risk of chronic diseases such as cancer and cardiovascular disease. Apple extracts have been shown to have the capabilities of inhibiting NF-kappaB activation in human breast cancer MCF-7 cells. 2Alpha-hydroxyursolic acid is one of the major triterpenoids isolated from apple peels, and its effects on cell proliferation and TNF-alpha-induced NF-kappaB activation in MCF-7 cells were examined. 2Alpha-hydroxyursolic acid significantly inhibited MCF-7 cell proliferation at doses of 20 microM (p < 0.05). Preincubation with 2alpha-hydroxyursolic acid suppressed TNF-alpha-induced NF-kappaB activation in a dose-dependent manner and significantly inhibited the activation at a dose of 20 microM of 2alpha-hydroxyursolic acid (p < 0.05). 2Alpha-hydroxyursolic acid treatment did not affect the phosphorylation level of NF-kappaB inhibitor (IkappaB-alpha), but proteasome activity in MCF-7 cells was inhibited significantly at doses of 10 and 20 microM ( p < 0.05). These results suggest that 2alpha-hydroxyursolic acid has antiproliferative activities against MCF-7 cells and capabilities inhibiting NF-kappaB activation induced by TNF-alpha partially by suppressing proteasome activities.  相似文献   
68.
Salmonella enterica subsp. enterica serovar Typhimurium was isolated from diarrheic piglets in 2 periods, 2000-2001 (n = 25) and 2005-2006 (n = 17). To compare the characteristics of the isolates collected during the 2 periods, all isolates were tested for antimicrobial resistance, the presence of virulence genes, and pulsed-field gel electrophoresis (PFGE) patterns. All 42 isolates were resistant to at least 1 of the 20 antimicrobials tested, and 39 (93%) were resistant to 2 or more antimicrobials. One isolate was resistant to 12 antimicrobials. Profiles of antimicrobial resistance revealed 20 resistance types. Several isolates were also resistant to quinolones and expanded-spectrum cephalosporins. Ten isolates (24%) were resistant to ampicillin, chloramphenicol, streptomycin, sulfonamides, and tetracycline (ACSSuT); only one isolate had been isolated in 2000-2001, indicating that this type of resistance has rapidly disseminated. Polymerase chain reaction (PCR) assays revealed that all the isolates carried invA. Among the 25 strains isolated in 2000-2001, all carried the sipA, sopA, sopD, sopE2, and ssaR genes, and 96% carried sopB and sifA. Among the 17 strains isolated in 2005-2006, all carried sifA, and approximately 90% carried sipA, sopA, sopB, sopD, sopE2, and ssaR. However, only 6 (14%) of the 42 isolates carried spvC. By PFGE analysis, all 42 strains were classified into 4 major clusters, basically by collection period. The genetic similarity according to PFGE suggests that the strains isolated from diarrheic piglets of this region within the same period may be closely related.  相似文献   
69.
BackgroundThe microsporidian parasite Nosema ceranae is a global problem in honeybee populations and is known to cause winter mortality. A sensitive and rapid tool for stable quantitative detection is necessary to establish further research related to the diagnosis, prevention, and treatment of this pathogen.ObjectivesThe present study aimed to develop a quantitative method that incorporates ultra-rapid real-time quantitative polymerase chain reaction (UR-qPCR) for the rapid enumeration of N. ceranae in infected bees.MethodsA procedure for UR-qPCR detection of N. ceranae was developed, and the advantages of molecular detection were evaluated in comparison with microscopic enumeration.ResultsUR-qPCR was more sensitive than microscopic enumeration for detecting two copies of N. ceranae DNA and 24 spores per bee. Meanwhile, the limit of detection by microscopy was 2.40 × 104 spores/bee, and the stable detection level was ≥ 2.40 × 105 spores/bee. The results of N. ceranae calculations from the infected honeybees and purified spores by UR-qPCR showed that the DNA copy number was approximately 8-fold higher than the spore count. Additionally, honeybees infected with N. ceranae with 2.74 × 104 copies of N. ceranae DNA were incapable of detection by microscopy. The results of quantitative analysis using UR-qPCR were accomplished within 20 min.ConclusionsUR-qPCR is expected to be the most rapid molecular method for Nosema detection and has been developed for diagnosing nosemosis at low levels of infection.  相似文献   
70.
Because of its requirement for signaling by multiple cytokines, Janus kinase 3 (JAK3) is an excellent target for clinical immunosuppression. We report the development of a specific, orally active inhibitor of JAK3, CP-690,550, that significantly prolonged survival in a murine model of heart transplantation and in cynomolgus monkeys receiving kidney transplants. CP-690,550 treatment was not associated with hypertension, hyperlipidemia, or lymphoproliferative disease. On the basis of these preclinical results, we believe JAK3 blockade by CP-690,550 has potential for therapeutically desirable immunosuppression in human organ transplantation and in other clinical settings.  相似文献   
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