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91.
We studied the change in the hypothalamo-pituitary-adrenal gland (HPA) axis upon adding prior toluene inhalation to our previous formaldehyde inhalation experiments to determine whether short term exposure to relatively high levels of toluene triggers multiple chemical sensitivity (MCS). Data come from immunocytochemical, morphometrical and RT-PCR measurements. Four groups of adult female mice were exposed to differing concentrations (0, 80, 400, and 2,000 ppb) of formaldehyde for 16 hr/day, 5 days/week for twelve weeks, after the mice were exposed intranasally to 500 ppm toluene per mouse for 6 hr/day, for 3 days. We found that the number of corticotropin releasing hormone (CRH)-immunoreactive (ir) neurons was up-regulated according to the amount of formaldehyde as well as inhalation of formaldehyde alone in our previous experiment. The proportion of adrenocorticotropin hormone (ACTH)-ir cells increased according to the formaldehyde concentration, though there was no significant difference between the 400 and 2,000 groups. The number of ACTH-ir cells was higher in the 400 group than in the other groups (0, 80, and 2,000). Expression of ACTH-mRNA was also up-regulated according to the quantity of formaldehyde. The sinusoid in the anterior pituitary showed more dilatation in the 400 and 2,000 groups than in the control group, especially in the 2,000 group. We propose that exposure to toluene prior to inhalation of formaldehyde has no effect on the HPA axis and as a trigger of MCS, although greater sinusoid dilatation was found in the anterior pituitary gland at higher concentrations of formaldehyde.  相似文献   
92.
To investigate the ecological importance of the cellulolytic bacterium Fibrobacter succinogenes in fiber digestion, ruminal distribution of F. succinogenes was determined in relation to its phylogenetic grouping. Rumen digesta from wethers and steers fed orchardgrass hay, rice straw or fresh orchardgrass were employed as the materials for the analyses. Orchardgrass hay stem incubated in the rumen was also used. By using total DNA extracted from these materials, population sizes of total F. succinogenes and of four different phylogenetic groups of this species were quantitated through competitive polymerase chain reaction (PCR), and restriction fragment length polymorphism analysis of PCR products targeted the bacterial 16S rDNA. Rumen digesta and ruminally incubated hay stems had a reasonably high population size of F. succinogenes (×107?8/g) that was composed of strains belonging to the phylogenetic groups 1 and 3. The relative abundance of each group was different among the samples; group 1 dominated on the ruminally incubated hay stem and in the rumen of wethers fed fresh orchardgrass, while group 3 was major in the rumen of wethers and steers on hay diet. These results suggest that there could be phenotypic differences among the phylogenetic groups of F. succinogenes, and group 1 dominating on hay stem might contribute to rumen fiber digestion more than the other groups.  相似文献   
93.
This study was conducted to evaluate the changes in acute-phase proteins and cytokine concentrations in dairy cows with naturally occurring peracute Klebsiella pneumoniae (K. pneumoniae) mastitis and their association with the outcome of the disease. Seventeen Holstein cows with K. pneumoniae mastitis from 8 dairy farms were divided on the basis of outcome after local and systemic therapy into 2 groups comprising 8 euthanized cows and 9 that recovered. Changes in acute-phase proteins and cytokine concentrations in cows with K. pneumoniae mastitis were evaluated at the onset of the disease (day 0) and at days 3, 7 and 14 after therapy and compared with those of 13 healthy dairy cows. The concentrations of haptoglobin (Hp) and interleukin (IL)-6 in serum and α(1)-acid glycoprotein and IL-1β in serum and whey on day 0 were significantly (P<0.05) higher in the euthanized cows than in those that recovered and the healthy cows. A correlation (r=0.90, P<0.01, n=17) was found between IL-6 and Hp concentrations in sera from recovered and euthanized cows at day 0. This indicated that serum concentrations of Hp and IL-6 at the initial examination were prognostic factors for survival, and the cutoff values were 2,020 μg/ml and 32 ng/ml, respectively. These results suggest that IL-6 and Hp concentrations are involved in the manifestation of K. pneumoniae mastitis and may be possible indicators of the prognosis of peracute K. pneumoniae mastitis.  相似文献   
94.
Holocellulose samples prepared from transgenic poplars overexpressing xyloglucanase had crystal widths of 3.2–3.5 nm as a result of the (2 0 0) plane, based on their X-ray diffraction patterns, and crystal widths were greater than those of the wild type (3.0 nm). Cellulose microfibril widths in the holocellulose samples were further determined from transmission electron microscopic (TEM) images of individualized fibrils prepared by 2,2,6,6-tetramethylpiperidine-1-oxy radical-mediated oxidation of the holocelluloses and the successive disintegration of the oxidized products in water. The TEM images also supported the finding that cellulose microfibril widths of transgenic poplars were larger than those of the wild type. The cellulose microfibril widths of transgenic poplars were approximately 6 nm, whereas those of the wild type were about 5 nm. However, such enlargement of cellulose microfibril widths could not be explained by the increased cellulose contents of the transgenic poplars alone.  相似文献   
95.
Absorption and metabolism of a natural compound, 6-O-caffeoylsophorose (CS) from acylated anthocyanins in a red vinegar fermented with purple sweet potato, were clarified. The absorption of CS and conjugated CS in blood from orally administrated Sprague-Dawley rats at a dose of 400 mg/kg was investigated by electrochemical detection-high performance liquid chromatography. As a result, CS was successfully detected in rat plasma (AUC(0-6h), 108.6 ± 8.1 nmol h/mL) and was found to be an intact absorbable polyphenol. In addition, half of the absorbed CS was detected as its conjugates (AUC(0-6h), 50.7 ± 5.7 nmol h/mL) as well as caffeic and ferulic acids from CS. By a time-of-flight-mass spectrometric analysis of CS-administered plasma sample, glucuronide and methylated conjugates of CS were identified, in addition to glucuronide, methylated, or sulfate conjugates of caffeic and ferulic acids. Consequently, CS was absorbed in intact form into rat blood and partly degraded to caffeic and ferulic acids or metabolized by glucuronidation, methylation, or sulfatation.  相似文献   
96.
ABSTRACT:   The installation depth of the hook in longline fishing gear has previously been measured with micro depth loggers. Research that assumes the catenary shape of longline fishing gear by a simulation based on these data has been done. However, it was not known whether the branch line was tangled with the main line or flowed with the current. In this research, an ultrasonic positioning system generally used to investigate the underwater behavior of marine organisms, and a buoy with a communications satellite, have been used, and the 3-dimensional underwater shape of tuna longline fishing gear was measured. It was possible to monitor changes in fishing gear in real time. The possibility of high precision measurement was suggested with future technical improvement.  相似文献   
97.
98.
Even though tetrodotoxin (TTX) is a widespread toxin in marine and terrestrial organisms, very little is known about the biosynthetic pathway used to produce it. By describing chemical structures of natural analogs of TTX, we can start to identify some of the precursors that might be important for TTX biosynthesis. In the present study, an analog of TTX, 5,11-dideoxyTTX, was identified for the first time in natural sources, the ovary of the pufferfish and the pharynx of a flatworm (planocerid sp. 1), by comparison with totally synthesized (−)-5,11-dideoxyTTX, using high resolution ESI-LC-MS. Based on the presence of 5,11-dideoxyTTX together with a series of known deoxy analogs, 5,6,11-trideoxyTTX, 6,11-dideoxyTTX, 11-deoxyTTX, and 5-deoxyTTX, in these animals, we predicted two routes of stepwise oxidation pathways in the late stages of biosynthesis of TTX. Furthermore, high resolution masses of the major fragment ions of TTX, 6,11-dideoxyTTX, and 5,6,11-trideoxyTTX were also measured, and their molecular formulas and structures were predicted to compare them with each other. Although both TTX and 5,6,11-trideoxyTTX give major fragment ions that are very close, m/z 162.0660 and 162.1020, respectively, they are distinguishable and predicted to be different molecular formulas. These data will be useful for identification of TTXs using high resolution LC-MS/MS.  相似文献   
99.
A rigid-type of polyethylene T-cannula was fitted into the anterior ileum of six horses in order to improve the cannulation techniques. A piece of polyethylene net was fastened onto the intestinal wall around the cannula to prevent dislodgment of the cannula by promoting a secure adhesion between the ileum and the abdominal wall. The cannula barrel sheathed with silicone tubing was exteriorized through a stab incision at the lateral ventral wall on the transverse line of the second lumber vertebra, and a flange was screwed onto the barrel. The feeding regime gradually increased concentrate without roughage prevented any colic signs. The use of these techniques succeeded in the ileal cannulation with no leakage of digesta.  相似文献   
100.
The aim of the present study was to detect quantitative trait loci affecting fatty acid composition in back fat and intramuscular fat in a Duroc pig population comprising seventh‐generation pedigrees using genome‐wide association studies (GWAS). In total, 305 animals were genotyped using single nucleotide polymorphisms (SNPs) array and five selected SNPs from regions containing known candidate genes related to fatty acid synthesis or metabolism. In total, 24 genome‐wide significant SNP regions were detected in 12 traits, and 76 genome‐wide suggestive SNP regions were detected in 33 traits. The Sus scrofa chromosome (SSC) 7 at 10.3 Mb was significantly associated with C17:0 in intramuscular fat, while the SSC9 at 13.6 Mb was significantly associated with C14:0 in intramuscular fat. The SSC12 at 1.0 Mb was significantly associated with C14:0 in back fat and the SSC14 at 121.0 Mb was significantly associated with C18:0 in intramuscular fat. These regions not only replicated previously reported loci containing some candidate genes involved in fatty acid composition (fatty acid synthase and stearoyl‐CoA desaturase) but also included several additional related loci.  相似文献   
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