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91.
There appears to be strong evidence supporting four major clades of placental mammals: (i) Afrotheria; (ii) Xenarthea; (iii) Euarchontoglires; and (iv) Laurasiathera. This is the first study in which the carbohydrates have been analyzed in the milks of Xenarthea. Our aim was to clarify whether the saccharides of giant anteater milk resemble those of other eutherian species, especially of the Asian elephant, which is one of the Afrotherea. We found that lactose is a dominant saccharide in this milk, as it is in that of most eutherians, and that the milk contains smaller amounts of oligosaccharides, whose structures were determined as Gal(α1‐3)Gal(β1‐4)Glc (isoglobotriose), Neu5Ac(α2‐6)Gal(β1‐4)Glc (6'‐N‐acetylneuraminyllactose), Neu5Gc(α2‐6)Gal(β1‐4)Glc (6'‐N‐glycolylneuraminyllactose), Neu5Ac(α2‐6)Gal(β1‐4)GlcNAc(β1‐3)Gal(β1‐4)Glc (LST c) and Neu5Gc(α2‐6)Gal(β1‐4)GlcNAc(β1‐3)Gal(β1‐4)Glc. This pattern of milk carbohydrates is rather close to that of the milks of other eutherian species. It is notable that the milk contained oligosaccharides with Neu5Gc residues but no oligosaccharides containing α(2‐3) linked Neu5Ac residues such as Neu5Ac(α2‐3)Gal(β1‐4)Glc.  相似文献   
92.
Consideration of the shortened fattening period seems to be worthwhile for the realization of profitable beef production. In this study, change of fatty acid composition of the lumbar longissimus during the final stage of fattening was investigated in Japanese Black cattle. Each of 110 fattening animals was sampled three times: the initial two samples were taken by biopsy (25.7 months and 27.5 months on average) and the final one was from carcasses (29.9 months on average). Preliminary analysis indicated that removing muscle tissues from the constant body position of the living animals should be essential for sampling. Average monounsaturated fatty acids (MUFA) at three sampling points were 58.1%, 58.5% and 60.5%, and the differences of the third sampling with the first and second samplings were significant. Both in steers and heifers, MUFA also increased as the fattening stage proceeded, and MUFA of the heifers at all the sampling points were significantly higher than those of the steers. The increasing rate of MUFA rose from 0.21 percentage points (pp)/month at period 1 (from the first sampling to the second sampling) to 0.84 pp/month at period 2 (from the second sampling to the slaughter).  相似文献   
93.
94.
Cancer-associated fibroblasts (CAFs) play an essential role in tumor invasion and metastasis. In dogs, the biological features of CAFs have not been well characterized. The purpose of this study was to investigate differences in the biological activities of canine CAFs and normal fibroblasts (NFs), and their influence on the migration and invasion of cancer cells. Canine CAFs and NFs were harvested from surgically-resected malignant epithelial tumor tissues and skin tissues of dogs. A wound-healing assay was conducted to compare the migratory and invasive abilities of canine CAFs and NFs. The results of this study showed that canine CAFs have a greater migratory and invasive ability than NFs. To observe the indirect and direct interactions between fibroblasts and cancer cells, Boyden chamber assay and 3D co-culture with collagen gel were conducted. The number of migrated and infiltrated cancer cells co-cultured with canine CAFs was greater than that with NFs. In the 3D co-culture, cancer cells showed noteworthy proliferation on the surface of gels containing canine CAFs and invasion into the gel. On the other hand, no infiltration of cancer cells into the gel containing NFs was observed. It was suggested that canine CAFs activate migration and invasion of cancer cells and promote the infiltration of cancer cells into collagen gels.  相似文献   
95.
Staphylococcus aureus produces staphylococcal enterotoxins (SEs) and causes food poisoning. It is known that almost all SE-encoding genes are present on various types of mobile genetic elements and can mobilize among S. aureus populations. Further, plasmids comprise one of SE gene carriers. Previously, we reported novel SEs, SES and SET, harbored by the plasmid pF5 from Fukuoka5. In the present study, we analyzed the distribution of these SEs in various S. aureus isolates in Japan. We used 526 S. aureus strains and found 311 strains positive for at least one SE/SE-like toxin gene, but only two strains (Fukuoka5 and Hiroshima3) were positive for ses and set among the specimens. We analyzed two plasmids (pF5 and pH3) from these strains and found that they were different. Whereas these plasmids partially shared similar sequences involved in the ser/selj/set/ses gene cluster, other sequences were different. A comparison of these plasmids with those deposited in the NCBI database revealed that only one plasmid had the ser/selj/set/ses cluster with a stop mutation in set similar to that in pH3. In addition, the chromosomes of Fukuoka5 and Hiroshima3, positive for ses and set, were classified into different genotypes. Despite the low rate of gene positivity for these SEs, it is suggested that there is diversity in plasmids and strains carrying these two SEs. Consequently, regarding the entire feature of SE prevalence, we improved the multiplex PCR detection method for the SE superfamily to obtain further insight.  相似文献   
96.
In humans, iron (Fe) and zinc (Zn) deficiencies result in major worldwide health problems. Transgenic technologies to produce Fe- and Zn-biofortified rice varieties offer a promising potential solution. Nicotianamine, the precursor of phytosiderophores, chelates Fe2+ and Zn2+ and plays an important role in transporting these metals to both vegetative and reproductive organs within the plant. Our objective was to increase Fe and Zn contents in rice grains by overexpressing the barley nicotianamine synthase gene HvNAS1. HvNAS1-overexpressing transgenic rice showed increased HvNAS1 expression and subsequent increases in endogenous nicotianamine and phytosiderophore content in shoots, roots, and seeds. Fe and Zn concentrations in polished T1 seeds from transgenic plants increased more than three and twofold, respectively; Fe and Zn concentrations also increased in both polished and brown T2 seeds. These results suggest that the overproduction of nicotianamine enhances the translocation of Fe and Zn into rice grains.  相似文献   
97.
The objective of this study was to quantify nitrogen (N), phosphorus (P) and potassium (K) utilization and their cycling in a beef-forage production system. A survey was conducted at the Kyoto University experimental farm in Kyoto Prefecture, Japan, and included 9.5 ha of meadow and about 160 head of beef cattle. Forages cultivated on the meadow were ensiled and offered to breeding cows. The whole farm was regarded as a beef-forage production system. The system consisted of three components: animals, manure and soil/crop. Nutrient inputs, flows through the soil-plant-animal pathway and outputs were quantified for 2 periods for the whole farm. Nutrient utilization was evaluated by nutrient balances, utilization efficiencies (ratio of nutrient export to nutrient input) and cycling index. The average nutrient balances of N, P and K for the whole farm (kg/year/ha) were 435.7, 136.3, and 262.8, and the average nutrient utilization efficiencies were 0.08, 0.06, and 0.01, respectively. The characteristics of nutrient balances and utilization efficiencies for each component differed among the nutrients. The average cycling indices for N, P and K were 0.19, 0.17 and 0.49, respectively. This study illustrates the importance of internal nutrient cycling for improving nutrient utilization in beef production systems.  相似文献   
98.
Tea (Camellia sinensis) leaves contain various antioxidants such as ascorbic acid (1) and polyphenols. This study tries to clarify the molecular mechanisms underlying the antioxidative and radical-scavenging activities of these antioxidants, and the reactivities of each antioxidant have been compared against that of the stable free radical 1,1-diphenyl-2-picrylhydrazyl (DPPH, 2) using nuclear magnetic resonance (NMR) analysis. Catechol (3) and (+)-taxifolin (4) were oxidized to o-quinone by 2. However, ethyl protocatechuate (5) and quercetin (6) were not oxidized to o-quinone, even though they possess a catechol structure. The radical-scavenging ability of o-dihydroxyl phenolic compounds with a conjugated olefinic double bond (e.g., 6) was superior to that of compounds without this bond (e.g., 4), whereas the ability of o-dihydroxyl phenolic compounds possessing a conjugated carbonyl bond (5) was inferior to that of compounds lacking this bond (3). Vicinal trihydroxyl phenolic compounds with a conjugated olefinic double bond [e.g., myricetin (7)] had an inferior scavenging ability as compared with compounds lacking this bond [e.g., pyrogallol (8)], but 7 was a better scavenger than compounds with a conjugated carbonyl double bond [e.g., ethyl gallate (9)]. In addition, vicinal trihydroxyl phenolic compounds (e.g., 9) were superior to o-dihydroxyl phenolic compounds (e.g., 6). Finally, 1 scavenged radicals more quickly than 8.  相似文献   
99.
Single cells prepared from autoclaved soybeans and cellulase treatment of the cells were effective in digesting the cell walls of and extracting the oil from soybeans. The first cell wall of the soybean single cell was completely removed using cellulases; the thin and transparent second cell wall of the cell was swollen. Oil in the cell formed spherical or hemispherical oil drops, and oil leaking from the oil bodies was observed. The oil was almost retained within the second cell wall. Water-extractable substances were obtained at approximately >60% of the weight. Flotation of oil drops by centrifugation was easily done. Ambient n-hexane extraction was also possible; however, residual oil remained in the oil bodies. Protease or peptidase digested the structure of the oil bodies; however, separation of the oil and the hydrolysates was impossible. The oil from the oil bodies was obtained effectively (>85%) by pressing the single cells and/or cellulase-treated single cells.  相似文献   
100.
Cleanliness of milking equipment is known to be important for the safety of dairy products and to prevent the spread of diseases among cows. We investigated the cleaning procedures of milking equipment and suckling equipment on Japanese dairy farms, and the cleanliness of bucket milkers, suckling buckets, milk receivers, and bulk tanks, using adenosine triphosphate (ATP) bioluminescence test. Bulk tanks (except one bulk tank) and milk receivers were washed by automated cleaning, but all bucket milkers and suckling buckets were washed by manual cleaning. Detergents were often not used to clean bucket milkers and suckling buckets. The log10 transformed relative luminescence units (LRLU) of equipment washed by manual cleaning was higher than equipment washed by automated cleaning. Clean surfaces (≤2.2 LRLU) were only observed on the bulk tank and the milk receiver. More than 50% of the LRLU of the mouthpiece, the rubber packing of claw, and the nipple of the suckling bucket were determined dirty. These results suggest that the cleanliness of the bucket milkers and the suckling buckets washed by manual cleaning was lower than that of the equipment washed by automated cleaning, and may be due to insufficient cleaning procedures.  相似文献   
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