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71.
The thermoxidative stability of partially hydrogenated soybean oil (PHSBO) was examined after addition of ferric stearate and ferrous octanoate, and then heating the samples at 120, 160, 180, and 200 degrees C. In a second experiment, the effect of iron concentration (ferric stearate) on PHSBO stability was examined at 180 degrees C, and at concentrations of approximately 0.5 and 1.2 mg of added iron/kg PHSBO. Oil samples were heated continuously for 72 h and sampled every 12 h. The acid value, p-anisidine value, color, dielectric constant and the triacylglycerol polymer content of oil samples were compared to oil samples containing no added iron. Generally, the value of each oxidative index increased with (1) an increase in temperature, (2) an increase in heating time, and/or (3) an increase in iron. The results demonstrate that low concentrations of iron will substantially increase the rate of oxidation for vegetable oil samples heated to temperatures of 120 degrees C to 200 degrees C.  相似文献   
72.
European Journal of Plant Pathology - The Allium cepa L. (onion) crop is affected by leaf blight disease caused by Stemphylium vesicarium; the shifts that S. vesicarium infection causes in the...  相似文献   
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Landscape ecology is a broad field in a patchwork of related disciplines. Giving landscape ecology a definition and delimiting it from related research areas is both a challenge and a necessity. Past endeavors have focused on expert opinions, analyses of published papers, and conference proceedings. We used a mix of all three, including a unique keyword analysis in two leading landscape-related journals, to highlight latest developments in landscape ecology between 2010 and 2013. Our analysis confirms the key topics of Wu (Landscape Ecol 28(1):1–11, 2013), and suggests that of those connectivity is dominating in terms of research output. However, we also found evidence that the borders of the journal Landscape Ecology are fuzzier than sketched in recent publications. There is a large overlap with the journal Landscape and Urban Planning, and in general a growing weight of conservation, landscape management, and planning related issues in the landscape ecology community. We conclude by encouraging the continued inclusion and strengthening of socio-ecological hot topics such as urban studies and landscape-human interactions in landscape ecological studies and subsequently in the journal landscape ecology.  相似文献   
75.

Background

It was recently shown that niacin supplementation counteracts the obesity-induced muscle fiber transition from oxidative type I to glycolytic type II and increases the number of type I fibers in skeletal muscle of obese Zucker rats. These effects were likely mediated by the induction of key regulators of fiber transition, PPARδ (encoded by PPARD), PGC-1α (encoded by PPARGC1A) and PGC-1β (encoded by PPARGC1B), leading to type II to type I fiber transition and upregulation of genes involved in oxidative metabolism. The aim of the present study was to investigate whether niacin administration also influences fiber distribution and the metabolic phenotype of different muscles [M. longissimus dorsi (LD), M. semimembranosus (SM), M. semitendinosus (ST)] in sheep as a model for ruminants. For this purpose, 16 male, 11 wk old Rhoen sheep were randomly allocated to two groups of 8 sheep each administered either no (control group) or 1 g niacin per day (niacin group) for 4 wk.

Results

After 4 wk, the percentage number of type I fibers in LD, SM and ST muscles was greater in the niacin group, whereas the percentage number of type II fibers was less in niacin group than in the control group (P < 0.05). The mRNA levels of PPARGC1A, PPARGC1B, and PPARD and the relative mRNA levels of genes involved in mitochondrial fatty acid uptake (CPT1B, SLC25A20), tricarboxylic acid cycle (SDHA), mitochondrial respiratory chain (COX5A, COX6A1), and angiogenesis (VEGFA) in LD, SM and ST muscles were greater (P < 0.05) or tended to be greater (P < 0.15) in the niacin group than in the control group.

Conclusions

The study shows that niacin supplementation induces muscle fiber transition from type II to type I, and thereby an oxidative metabolic phenotype of skeletal muscle in sheep as a model for ruminants. The enhanced capacity of skeletal muscle to utilize fatty acids in ruminants might be particularly useful during metabolic states in which fatty acids are excessively mobilized from adipose tissue, such as during the early lactating period in high producing cows.  相似文献   
76.
This study assessed the effects of five different transport periods on physiometabolic responses and gas exchange in ostriches. It included 138 ostriches that were assigned to five experimental groups. G1 included 78 birds that were set aside as a reference group (RG). Each one of the four remaining experimental groups included 20 ostriches, which were transported in the following manner: G1 on one occasion for a period of 1 h; G2 on one occasion for 2 h; and G3 on one occasion for 3 h; G4a was made up of the ostriches from G1 but they were shipped on a second occasion, for 2 h (making a total of 3 h); finally, G4b was that same group, but after a third transport period, on this occasion during 3 h (for a total of 6 h). Groups G2 and G3 presented the most marked blood alterations (P < 0.05), including an increase in pH, hypocapnia (27.8 ± 0.80 mmHg), hypernatremia (171.75 ± 1.84 mmol/L), hypocalcemia (0.95 ± 0.03 mmol/L), and hyperglycemia (224.05 ± 3.94 mg/dL). Also, group G3 presented the lowest hematocrit values (26.5 ± 0.47 HTC%). Therefore, transporting ostriches with no prior experience for 3 h caused the most pronounced physiometabolic changes.  相似文献   
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79.
The common bean can obtain nitrogen (N) from the decomposition of the soil organic matter, mineral fertilizers, and biological nitrogen fixation (BNF). This study aimed to evaluate the behavior of nodulation parameters related to BNF throughout the development of common bean cultivars with different growth cycles. The experiments were conducted for two consecutive years (2012 and 2013) with 22 common bean cultivars with different growth cycles. The common bean cultivars were inoculated with a mixture of Rhizobium tropici strains (SEMIA 4077, SEMIA 4080, and SEMIA 4088). In 2012, samplings were performed from the V4 to the R8 stage, and the parameters related to nodulation and crop growth were evaluated at each stage and in the R9 stage, the grain yield and its components were measured. For the 2013 experiment, the same evaluations were performed but the nodulation parameters were only measured in the R6 and the R7 stages. Differences in the number and activity of the nodules along the development of the cultivars were observed. For the early and semi-early cycle cultivars, the activity of the nodules was observed until the R7 stage, while for the regular and late cycle cultivars, this activity only occurred until the R6 stage, resulting in three more days of nodule activity for the early and semi-early cycle cultivars as compared to the regular and late ones. The number of nodules correlated significantly with the shoot dry weight and the shoot Total-N; while the nodules dry mass showed a significantly high correlation with both parameters. The overall mean grain yield was 2,766.75 kg ha?1. However significant difference related solely to the various cultivars cycles were not observed.  相似文献   
80.
Nematodes have difficult control and complex handling, but considering the physiological and biochemical changes that micronutrients promoting in plants, there is possibility that the supply with these chemicals increases the resistance of plants against nematodes. Thus, the present study aimed to assess the effect of the application of boron and zinc on the reproduction of Meloidogyne incognita, embryonic development and juvenile nematode hatching. Nematode reproduction was evaluated in tomato plant inoculated with 2000 eggs and treated in the aerial part with boron or zinc at the following doses: 0, 1/2, 1×, 2× and 4× the manufacturer's recommendation (100 and 30?g/L, respectively), with the plants assessed 60 days after inoculation. For assessment of embryonic development and juvenile hatching, 1?mL nematode suspension was placed in Petri dishes containing 9?mL of the same doses of boron and zinc, and assessment occurred four and eight days after incubation. Results obtained showed that boron controlled nematode population at the dose of 400?g/L and promoted juvenile hatching when used at maximum dosage on the eighth day. Zinc reduced the number of galls and the number of eggs at the dose of 60?g/L, but did not exhibit direct effect on nematode.  相似文献   
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