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431.
From porcine rectal swabs or feces, we isolated lactic acid bacteria and used porcine Peyer's patch cells to select them for inducibility of IgA production as an indicator of probiotic effects. The strain selected as a new probiotic was named ‘Enterococcus faecium NHRD IHARA‘. To verify the probiotic effects of this strain in vivo, 536 piglets at age 25 days were assigned to either the trial group, which administrated the strain, or the control group. An increase in IgA in the feces was observed at age 45 days (P < 0.05 compared with the control group); a significant increase in serum IgA was also observed at the end of the study (P < 0.01) in the trial group. In addition, significant differences between the groups in terms of body weight (P < 0.05) and average daily gain (P < 0.01) were observed. The rate of detection of swine‐pathogenic Escherichia coli gene in the feces tended to be lower in the trial group than in the controls. The novel probiotic strain; E. faecium NHRD IHARA may have beneficial effects on swine growth by inducing IgA production and reducing rates of colonization by pathogens in the body.  相似文献   
432.
Recent studies demonstrated that perforated pit membranes (i.e., pit membranes with a large opening in their central portion) are commonly present between wood fibers in core eudicots. It is unclear whether this type of pit membranes might also occur in ancestral angiosperms. Therefore, structure of interfiber pit membranes was examined by field-emission scanning electron microscopy in nine species representing seven families that are located at more ancestral position than core eudicots. We found perforated pit membranes in three of the nine species. Our observations indicate that perforated pit membranes are relatively common even in ancestral groups of angiosperms. In the non-perforated pit membranes of the other six species, we found a range of structural variations. Thin-walled pit membranes without apparent intercellular layers were always found in three of the six species and the porosity of sheet-like pit membranes differed among the three species. Unlike the thin-walled pit membranes, interfiber pit membranes of Buxus microphylla var. japonica were thick-walled with obvious intercellular layers, and in Schisandra chinensis, we often observed torus-bearing pit membranes. Such variations in layered structure of pit membranes and homoplastic occurrence of torus-bearing pit membranes have not yet been reported for ancestral angiosperms. Our observations indicate that the structure of interfiber pit membranes might be more complicated than previous studies might suggest.  相似文献   
433.
Nonhuman primates are commonly used as experimental animals due to their biological resemblance to humans. In patients with cardiac disease, the levels of atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP) tend to increase in response to cardiac damage, and they are thus used as indicators for the diagnosis of human heart failure. However, no reference values for ANP and BNP have been reported for heart disease in nonhuman primates. In this study, we recorded the age, sex, and body weight of 202 cynomolgus monkeys, and performed evaluations to assess the ANP and BNP levels, electrocardiography and echocardiography, and accordingly divided the monkeys into two groups: healthy monkeys and those with spontaneous cardiac disease. Statistical analysis was performed to determine the relationship of ANP and BNP with the factors of age, sex, and body weight. No significant relationship was found between the levels of ANP and BNP and the factors of age, sex, and body weight. However, both the ANP and BNP levels were significantly different between the healthy monkeys and monkeys with valvular disease. Similar to humans, the ANP and BNP levels tended to increase with the progression of cardiac disease in monkeys. Based on these results, we concluded that ANP and BNP are indicators of cardiac disease in nonhuman primates, and that this nonhuman primate cardiac disease model is applicable for cardiology research in humans.  相似文献   
434.
Cloning and characterization of cDNA for carp matrix metalloproteinase 9   总被引:1,自引:0,他引:1  
ABSTRACT: We have cloned a cDNA encoding the MMP-9 from a carp epidermal cell (EPC) cDNA library. The clone contains a 2025-base pair (bp) open reading frame encoding a protein of 674 amino acids. The deduced amino acid sequence shares 68% and 69% identity with medaka and Japanese flounder MMP-9. The hinge domain of the carp MMP-9, like those of the other non-mammalian species, lacks a type V collagen-like region that is typical of mammalian MMP-9. Gelatin zymography and immunoblot analysis of conditioned media of EPC cells and cDNA-transfected COS-7 cells detected a 76-kDa gelatinase. The apparent molecular mass of the carp zymogen is much smaller than those of its mammalian counterparts while almost identical with that of chicken 75-kDa gelatinase B-like enzyme. Although hypo-osmotic stress induced the elevation of MMP-9 mRNA level in EPC cells, no significant change in the protein in conditioned medium was detected during hypo-osmotic stress. Northern blot analysis detected a large amount of MMP-9 mRNA in carp kidney and spleen, suggesting the high expression of MMP-9 in blood cells, neutrophils, and macrophages. The smaller amount of MMP-9 mRNA was detected in gill, heart, fin, and eye, whereas none of the mRNA was detected in the hepatopancreas, intestine, brain, muscle, and skin.  相似文献   
435.
cDNA cloning and characterization of two gelatinases from Japanese flounder   总被引:1,自引:1,他引:1  
SUMMARY: Toughness is one of the most important elements that define the commercial value of the raw meat of fish. Degradation of the extracellular matrix is thought to be a cause of postmortem tenderization of fish meat. A previous study has suggested that this tenderization is caused mainly by metalloproteinases. The present study seeks to identify the proteinase(s) involved in tenderization; hence, cloned cDNA of two gelatinases from Japanese flounder, which showed high homology with mammalian matrix metalloproteinase (MMP)-2 and MMP-9, were designated as jfMMP-2 and jfMMP-9 , respectively. Northern blot analysis revealed that jfMMP-2 mRNA was expressed almost ubiquitously in adult tissues including the brain, muscle, gill, heart, gut, kidney, spleen, testis, and ovary. In contrast, the expression of jfMMP-9 mRNA was observed in those tissues which were abundant in blood cells, such as kidney, spleen, heart, and gill. Both recombinant proteins (jfMMP-2 and jfMMP-9) produced with the COS-7 cell system exhibited gelatin-degrading activity that was sensitive to 1,10-phenanthroline, a typical metalloproteinase inhibitor.  相似文献   
436.
ABSTRACT: This study attempted to reduce the lipid and water contents in boiled skipjack loins by vacuum treatment and the quality of vacuumed boiled meat was then evaluated during the chilled and frozen storage. The boiled meats were vacuumed at a pressure of 400 Pa for 30 min using a vacuum freeze dryer as an experimental convenience in order to degrease, cool and dehydrate rapidly. The vacuumed boiled meats were stored at 0.0 ± 0.2°C for 10 days and at −20 ± 0.5°C for 90 days. The unvacuumed boiled meats were cooled by air-cooling and stored as the control. Lipid content on a wet basis (w.b.) was reduced as much as 0.5% in the ventral part and 0.4% in the dorsal part of the boiled meats after vacuum treatment. Water content (w.b.) was reduced as much as 2.5% in the ventral part and 3.0% in the dorsal part. The thiobarbituric acid and volatile basic nitrogen values in vacuumed boiled meats were significantly lower ( P < 0.05) than that in unvacuumed boiled meats during storage. Inosine monophosphate (IMP) was only detected as a major nucleotide (about 70%) in boiled meats, and the decomposition of IMP in vacuumed boiled meats was smaller than that in unvacuumed boiled meats during storage. It was concluded that the quality of boiled skipjack loins could be improved by vacuum treatment as a preprocessing procedure in the production of dried skipjack such as katsuobushi .  相似文献   
437.
ABSTRACT:   The dynamics of vitamin A (VA) compounds in live food during enrichment were examined under different light conditions. Rotifers Brachionus plicatilis and Artemia nauplii ( Artemia ) were enriched with or without 10 mg VA palmitate (VAp) in 1 L of culture medium for 24 h under either bright (2000 lx), or dark (<1 lx) conditions. VAp, retinol (ROH), retinal (RAL) and retinoic acid (RA) contents were analyzed at 0 h (before enrichment) and at 3, 6, 12, 18 and 24 h after the onset of enrichment. Retinoid content in rotifers enriched in darkness was always higher than that enriched under light. VAp content showed two peaks at 3 and 18 h in rotifers enriched in darkness, but it showed one peak at 3 h in rotifers enriched under light. ROH and RA contents increased over the 24-h period in rotifers enriched in darkness, whereas they decreased 12 h onward in rotifers enriched under light. In Artemia , VAp and ROH contents were always higher than when enriched under the bright condition, but their dynamics showed a similar pattern in Artemia enriched under dark and bright conditions.  相似文献   
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