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21.
A qualitative and quantitative analysis of rutin from leaves, fruits and flowers of Capparis spinosa growing wild in Khuzestan was achieved. After soxhelet extraction of fats in diethyl ether, rutin was extracted by maceration using 50% EtOH. The ethanol extracts of these parts were separated by preparative TLC on silica gel precoated plate with a mixture of butanol: acetic acid (4:1, by volume) as the developing solvent. The spots were visualized under ultraviolet light (254 nm). Rutin was qualified by comparison of its R(f) value with that of standard. UV/Vis spectrum of separated rutin was also compared with those of standards and showed characteristic wavelengths at 260 and 360 nm. Purified rutin was quantified by UV/Vis spectrophotometric determination at 360 nm. The calibration curve was linear in the range of 0.156-2.5 microg mL(-1) with detection limit of 0.0731 microg mL(-1). The purity of extracted rutin from leave, flower and fruit determined by high performance liquid chromatography were 90.41, 87.25 and 64.56%, respectively. The amounts of rutin in leaves, fruits and flowers were 61.09, 6.03 and 43.72 mg per 100 g of dried powder, respectively. By analyzing the spiked samples of leave, flower and fruit the recovery of the UV/Vis method was in the range of 102-107.6%.  相似文献   
22.
Neospora caninum, an apicomplexan protozoan parasite, is recognized as a major cause of abortion in cattle. Surface antigen 1 of N. caninum (NcSAG1) is an important immunodominant candidate for the development of a diagnostic reagent for neosporosis. The present study describes the development and evaluation of a latex agglutination test (LAT) with recombinant NcSAG1 (rNcSAG1) for the detection of antibodies to N. caninum in cattle. The rNcSAG1 gene was cloned in pET-28a and protein was expressed in Escherichia coli BL21 (DE3). Carboxylated latex particles were coated with rNcSAG1 and the degree of agreement between LAT and a commercial enzyme-linked immunosorbent assay (iscomELISA) was evaluated by using of 164 serum samples. Twenty-two (13.4%) and 23 (14.0%) of samples were positive for antibodies to N. caninum by LAT and ELISA respectively. Eighteen of 23 ELISA-positive samples were positive according to the LAT and a substantial agreement (κ=0.77) was found between the results of LAT and ELISA. The results indicated that the LAT with rNcSAG1 would be a rapid, simple, relatively inexpensive and suitable diagnostic test for detection of specific antibodies in N. caninum infection under field conditions. Improvement in purification of rNcSAG1 can reduce probable false positive reactions and so increase the degree of agreement between the LAT and ELISA.  相似文献   
23.
Considering the importance of the poultry industry and the increasing interest in alternative growth promoters, probiotics are considered as a potential candidate for use in the poultry industry. In this study, Lactobacillus species were isolated from 21 rectal swabs of 11 healthy 6-day-old and 10 healthy 21-day-old chickens and their fecal and feed samples. The isolates were characterized and their probiotic characteristics, including resistance to gastric acid and bile salts, biofilm formation and adherence to epithelium or mucus, amylase and protease activity and production of inhibitory compounds, were assessed. From 31 acid and bile resistant lactobacilli, only 2 Lactobacillus brevis and 1 Lactobacillus reuteri strains showed significant probiotic properties. These isolates indicated detectable attachment to Caco-2 cells and significant antibacterial activities against Gram-positive and Gram-negative pathogens. Additionally, phenotypic and genotypic diversity of lactobacilli isolates were studied by Phene Plate (PhP) system (PhP-LB) and random amplified polymorphic DNA (RAPD)-PCR, respectively. PhP-LB results of 24 L. brevis isolates showed a high phenotypic variation among the isolates. In comparison, results of RAPD-PCR highlighted a low diversity. Therefore, it seems that combination of the 2 techniques (PhP and RAPD-PCR) could result in a significant discriminatory power than each of them used alone.  相似文献   
24.
Background: This study was conducted to evaluate fibroblast co-culture and Activin A on in vitro maturation and fertilization of mouse preantral follicles. Methods: The ovaries from 12-14-day-old mice were dissected, and 120-150 μm preantral follicles were cultured individually in α-MEM as based medium for 12 days. A total number of 456 follicles were cultured in four conditions: (i) base medium as control group (n = 113), (ii) base medium supplemented with 30 ng/ml Activin A (n = 115), (iii) base medium co-cultured with mouse embryonic fibroblast (n = 113), and (iv) base medium supplemented with 30 ng/ml Activin A and co-cultured with fibroblast (n = 115). Rate of growth, survivability, antrum formation, ovulation, embryonic development and steroid production were evaluated. Analysis of Variance and Duncan test were applied for analyzing. Results: Both co-culture and co-culture + Activin A groups showed significant difference (P<0.05) in growth (on days 4, 6, and 8 of culture period) and survival rates. However, there was no significant difference in antrum formation, ovulation rate, and embryonic development of ovulated oocytes. There were significant differences (P<0.05) in the estradiol production on days 8, 10, and 12 between co-culture + Activin A and the control group. Progesterone production also was significant (P<0.05) in co-culture + Activin A group on days 6, 8, 10, and 12 compared to control group. Conclusion: Fibroblast co-culture and Activin A promoted growth and survivability of preantral follicles. However, simultaneous use of them was more efficient. Key Words: Fibroblast, Activin A, Follicle  相似文献   
25.
Three segments of cattle small intestine (duodenum, upper jejuno‐ileum and lower jejuno‐ileum) were examined in an in vitro system for activity of ornithine carbamoyltransferase (OCT; EC 2.1.3.3) which is involved in the synthesis of citrulline (Cit) from ornithine (Orn). The mucosa of the three segments of small intestine was collected from Japanese black cattle, homogenized and then centrifuged. The supernatant fraction was used as the crude OCT enzyme solution. The OCT activity was assayed by the production of Cit from Orn determined directly by HPLC. The optimal pH and temperature for OCT activities in the duodenum, upper jejuno‐ileum and lower jejuno‐ileum of cattle small intestine were 7.47 and 39°C. Little difference was observed between the three segments. The OCT activity in cattle kidney was also examined for comparison, and almost no activity was found. The OCT activities in crude enzyme solutions of the three segments of small intestine were stable for up to one month of storage at ?20°C in Tris HCl buffer solution. Finally, the role of the small intestine in supplying Cit as a precursor for arginine synthesis in cattle kidney was discussed.  相似文献   
26.
A survey was conducted to investigate the physiological levels of pipecolic acid (Pip) in rumen fluid and plasma of ruminants such as goats and cattle in the presence or absence of rumen protozoa. The concentration of Pip was determined using HPLC. Basal Pip levels in the rumen fluid and plasma of normal faunated animals were 21 ± 8 and 2.3 ± 1.3 µM, respectively, and levels increased 1–2 h after feeding. The Pip levels in the rumen fluid and plasma of faunated goats and cattle were significantly higher than those of defaunated goats and unfaunated cattle. A small amount of Pip was also found in the rumen fluids of the defaunated and unfaunated animals; this appeared to be derived from feeds such as hay cube and corn silage. The results obtained in the present study suggest that a significant amount of rumen‐produced Pip is likely to be absorbed into the plasma of the host animals and that rumen protozoa significantly enhance the concentration of Pip in the rumen fluid and plasma of ruminant animals.  相似文献   
27.
As saline soils dry, the salt in the remaining solution phase is concentrated and the microbes are subjected to both water and osmotic stress. However, little is known about the interactive effect of matric potential (MP) and osmotic potential (OP) on microbial activity and community structure. We conducted an experiment in which two non-saline soils, a sand and a sandy loam, were pre-incubated at optimal water content (for microbial activity) but different osmotic potentials achieved by adding NaCl. The EC of the saturated paste (ECe) ranged between 1.6 and 11.6 dS m−1 in the sand and between 0.6 and 17.7 dS m−1 in the sandy loam. After the 14-day pre-incubation, the soils were dried to different water contents: 25-35 g kg−1 in the sand and 95-200 g kg−1 in the sandy loam. Water potential (WP, the sum of osmotic + matric potential) ranged from −0.7 to −6.8 MPa in the sand and from −0.1 to −4.4 MPa in the sandy loam. After addition of ground pea straw to increase the concentration of readily available substrate, respiration was measured over 14 days and microbial community composition was assessed by phospholipid fatty acid analysis (PLFA) at the end of the experiment. In both soils, cumulative respiration at a given soil water content (WC) decreased with decreasing osmotic potential, but the effect of decreasing water content differed between the two soils. In the sand, cumulative respiration at the two lowest water contents (WC25 and WC28) was always significantly lower than that at the highest water content (WC35). In the sandy loam, cumulative respiration was significantly lower at the lowest water content (WC95) compared to the highest water content (WC200) only in treatments with added salt. The reduction of cumulative respiration at a given WP was similar in the two soils with a 50% reduction compared to the control (optimal water content, no salt added) at WP −3 MPa. In the sand at WP <−2 MPa, the reduction in fungal fatty acids was greater than that of bacterial fatty acids whereas in the sandy loam, the response of bacteria and fungi to decreasing WP was similar. In both soils, microbial biomass decreased by 35-50% as WP decreased to about −2 MPa but then remained stable with further decreases of WP. Microbial community composition changed with WP in both soils. Our results suggest that there are two strategies by which microbes respond to water potential. A decrease in WP up to −2 MPa kills a proportion of the microbial community, but the remaining microbes adapt and maintain their activity per unit biomass. At lower WP however, the adaptation mechanisms are not sufficient and although the microbes survive, their activity per unit biomass is reduced.  相似文献   
28.
The present study investigated the arsenic (As) remediation potential of barnyard grass (Echinochloa crus‐galli L. Beauv. var. formosensis Ohwi), with a special focus on the behavior of As in the soil in comparison with rice (Oryza sativa L. cv. Nipponbare). For both plants, very little growth inhibition was observed in the As‐contaminated soil. The amount of As in the soil was reduced by the plant's uptake and the level of As in the soil water from the rice‐growing pots was remarkably lower than that in the plant‐free soil water. In the soil with the barnyard grass, the amount of As in the soil water was higher than that in the plant‐free soil water, but the amount of As in the soil and the amount of As that was adsorbed on the soil solid were reduced by the plant's uptake. At the highest As level in the soil (100 mg kg?1), 249.60 and 101.26 µg As pot?1 were taken up by the rice shoot and barnyard grass shoot, respectively, and total amounts of 1468.65 and 1060.57 µg As pot?1 were taken up by the barnyard grass and rice seedlings, respectively. At the same As level in the soil, the As concentrations were 14.99 and 37.76 µg g?1 in the shoot of barnyard grass and rice, respectively, and 486.61 and 339.32 µg g?1 in the root of barnyard grass and rice, respectively. Barnyard grass took up more As than rice, but the As concentration in the shoot of barnyard grass was lower than that in the shoot of rice. A considerable amount of As was taken up by both barnyard grass and rice, suggesting that the plant species have the potential to remediate As‐contaminated soil.  相似文献   
29.
30.
In vitro experiments were conducted to examine the synthesis of arginine (Arg) from argininosuccinic acid (ASA) and citrulline (Cit) by crude enzymes of cattle kidney cortex. Kidney samples, collected from Japanese black cattle, were homogenized in KCl solution (ice‐cold), and centrifuged at 27 000 × g for 20 min at 4°C, and the supernatant fluid was used as a crude enzyme solution. The enzyme solution was incubated at 39°C in Tris HCl buffer with 15 mmol/L ASA or with 10 mmol/L Cit in the presence of 10 mmol/L aspartic acid (Asp), 10 mmol/L ATP and 5 mmol/L MgCl2 to examine the activities of two enzymes, argininosuccinate lyase and argininosuccinate synthetase, which work at the terminal steps of Arg biosynthesis. The production of Arg from ASA, or ASA and Arg from Cit by argininosuccinate lyase and argininosuccinate synthetase activities, respectively, were determined directly by the HPLC method. The optimum pH for argininosuccinate lyase activity was 7.85. Unfortunately, the optimum pH for argininosuccinate synthetase activity could not be determined because no inhibitor of argininosuccinate lyase was used in the Cit incubation, so the ASA produced from Cit spontaneously converted to Arg during incubation with Cit. The maximum production of ASA from Cit was found at pH 6.45 under these conditions. We observed the optimum pH for the synthesis of Arg from Cit at 7.7. The production of Arg from ASA or Cit was quantitatively determined as 14.4 or 8.83 µmol/g kidney tissue/h, respectively, at the optimal pH values. This suggests that the daily production of Arg from ASA or Cit by the kidney might be sufficient to cover the daily requirement of Arg in cattle.  相似文献   
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