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The squid pen (gladius) from the Loligo vulgaris was used for preparation of β-chitin materials characterized by different chemical, micro- and nano-structural properties that preserved, almost completely the macrostructural and the mechanical ones. The β-chitin materials obtained by alkaline treatment showed porosity, wettability and swelling that are a function of the duration of the treatment. Microscopic, spectroscopic and synchrotron X-ray diffraction techniques showed that the chemical environment of the N-acetyl groups of the β-chitin chains changes after the thermal alkaline treatment. As a consequence, the crystalline packing of the β-chitin is modified, due to the intercalation of water molecules between β-chitin sheets. Potential applications of these β-chitin materials range from the nanotechnology to the regenerative medicine. The use of gladii, which are waste products of the fishing industry, has also important environmental implications.  相似文献   
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Bread wheat (BW) and durum wheat (DW) are both strongly affected by Septoria tritici blotch caused by the hemibiotrophic fungus Zymoseptoria tritici. However, only the BW-Z. tritici pathosystem has been well studied so far. Here, we compared compatible interactions between Z. tritici and both BW and DW species at the cytological, biochemical and molecular levels. Fungal infection process investigations showed close spore germination and leaf penetration features in both interactions, although differences in the patterns of these events were observed. During the necrotrophic phase, disease severity and sporulation levels were associated in both interactions with increases of the two cell-wall degrading enzyme activities endo-β-1,4-xylanase and endo-β-1,3-glucanase as well as protease. An analysis of plant defense responses during the first five days post inoculation revealed inductions of GLUC, Chi4, POX and PAL and a repression of LOX gene expressions in both wheat species, although differences in kinetics and levels of induction or repression were observed. In addition, peroxidase, catalase, glucanase, phenylalanine ammonia-lyase and lipoxygenase activities were induced in both wheat species, while only weak accumulations of hydrogen peroxide and polyphenols were detected at the fungal penetration sites. Our study revealed overall a similarity in Z. tritici infection process and triggered wheat defense pathways on both pathosystems.  相似文献   
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Effects of physiological saline (PS)-dissolved or Freund′s incomplete adjuvant (FIA)-emulsified sGnRHa on the induction and advancement of ovulation in brook char were assessed. Two-year-old females were randomly divided into 5 groups. Groups A and B received intraperitoneal injection of FIA-emulsified sGnRHa (sGnRHa-FIA) at dosages of 50 and 25 μg kg?1 body weight (BW), respectively. Females in group C were treated with a double injection (DI) of PS-dissolved sGnRHa (sGnRHa-PS) at 25 μg kg?1 BW spaced 3 days apart. Fish in group D received a 25 μg kg?1 BW single injection (SI) of sGnRHa-PS. Group E was established as a control group. After stripping, ovarian plasma pH level was measured, and an egg sample was taken from each female to record egg weight and diameter and survival to the eyed stage. Females in the GnRHa-treated groups ovulated significantly earlier than did females in the control group (P < 0.01). No significant differences were found among GnRHa-treated groups in ovulation dynamics and mean time to ovulation. Ovarian fluid pH was significantly higher in groups A, B, and C compared to control group E (P < 0.05). Significantly lower egg weight was found only in group B (P < 0.01), although all advanced groups tended to have lower egg weight than the control group. Egg diameters paralleled egg weight. Survival to the eyed stage was significantly higher in GnRHa-advanced groups compared to the control. A negative relationship was found between egg weight end eyed eggs percent (R 2 = 0.26). No pre-spawning or post-spawning mortality was observed during a 6-month period. Neither sGnRHa-PS nor sGnRHa-FIA are associated with negative influences on the health of females. The sGnRHa-FIA injections proved to exhibit the same efficacy as the DI protocol with sGnRHa-PS. Although no statistical differences were found in ovulation dynamics, we do not recommend the use of SI with sGnRHa-PS in brook char.  相似文献   
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Enzyme treatment technologies in textile processing have become commonly-applied techniques for the modification of fabric-handle appearance, and other surface and mechanical characteristics of fabrics. Most studies have focused on understanding the impact of enzyme treatments on the fabric preparation, dyeing, and finishing processes of woven fabrics, whilst only limited research has been reported regarding any enzymatic effects on the surface and handproperties of knitted fabrics. The aim of this study was to analyze the effects of two different enzymes Trichoderma reesei whole cellulase, and enriched (EGIII) endoglucanase cellulase, at three different enzyme dosages on 100 % cotton interlock knitted fabric. This was in order to evaluate certain surface properties such as pilling, friction. and geometrical roughness. Furthermore, the compression and tactile properties of knitted fabric were also analyzed. The results show that treatment conditions with enzyme Trichoderma reesei whole cellulase had the more pronounced effect on the surface properties compared to the enriched EGIII enzymes. In general, it can be concluded that both types of enzymes improved the surface properties and hand when compared with the silicone softener-treated reference sample of interlock knitted fabric, as is statistically confirmed by one-way analysis of variance.  相似文献   
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We hypothesized that fruit ingestion provides measurable amounts of salicylic acid (SA) and produces different metabolic and inflammatory responses compared to mere fruit sugars. In a randomized-crossover study, 26 healthy subjects received a peach shake meal (PSM) (SA: 0,06 ± 0,001 mg/100 g) and a mixed sugar meal (MSM), consisting in an aqueous solution with the same sugars found in the peach shake. In order to control for the SA contribution from meals in the previous day, 16 subjects (Group 1) abstained from fruits and vegetables consumption the evening before trials, and 10 subjects (Group 2) maintained their usual diet. Circulating SA, glucose, insulin, free fatty acids, and interleukin-6 were determined. Basal SA was lower in Group 1 than in Group 2 (0.09 ± 0.02 vs. 0.30 ± 0.03 μmol/l, p < 0.001), peaked at 90 min in both groups (0.18 ± 0.01 vs. 0.38 ± 0.02 μmol/l, p < 0.01) and remained above baseline (p < 0.05) up to 3 h. Glycemia increased less after PSM at 15 min (p < 0.01) with a lower average glucose excursion (p < 0.05). Insulin peaked at 45 min with both meals but decreased less rapidly with PSM. Free fatty acids decreased more (p < 0.01), and interleukin-6 increased less (p < 0.05) with PSM. Dietary fruit intake increases the concentration of SA in vivo, and provides non-nutrients capable to modulate the inflammatory and metabolic responses to carbohydrates.  相似文献   
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