全文获取类型
收费全文 | 238篇 |
免费 | 3篇 |
专业分类
林业 | 30篇 |
农学 | 4篇 |
46篇 | |
综合类 | 9篇 |
农作物 | 4篇 |
水产渔业 | 28篇 |
畜牧兽医 | 100篇 |
园艺 | 3篇 |
植物保护 | 17篇 |
出版年
2022年 | 1篇 |
2021年 | 6篇 |
2020年 | 8篇 |
2019年 | 4篇 |
2018年 | 4篇 |
2017年 | 5篇 |
2016年 | 4篇 |
2015年 | 13篇 |
2014年 | 7篇 |
2013年 | 16篇 |
2012年 | 15篇 |
2011年 | 19篇 |
2010年 | 6篇 |
2009年 | 9篇 |
2008年 | 17篇 |
2007年 | 24篇 |
2006年 | 14篇 |
2005年 | 13篇 |
2004年 | 20篇 |
2003年 | 14篇 |
2002年 | 10篇 |
2001年 | 5篇 |
2000年 | 2篇 |
1999年 | 1篇 |
1998年 | 1篇 |
1996年 | 2篇 |
1992年 | 1篇 |
排序方式: 共有241条查询结果,搜索用时 15 毫秒
11.
As a measure of estimating humidity control capacity of materials in an airtight room under sinusoidal temperature variation,
we used the Cb value, which is the ratio of the range of variation in relative humidity in a steel box lined with the material of interest
to the range in an empty steel box. In order to clarify the factors that affect the Cb value, we focused on both the temperature variation rate and the area that is lined in the box. It was found that changing
the rate of temperature variation over one period strongly affected the Cb value, although the amplitude of temperature variation did not. We further noticed that the difference between the time when
peak temperature was reached and the time when peak absolute humidity was reached (peak time difference), was found to be
useful for estimating the humidity control capacity of materials. Knowing the difference between the phase when peak temperature
was reached and the phase when peak absolute humidity was reached (phase angle difference) was also useful. Because the Cb value was affected by both the variation period and the lined area in the box, we can draw a contour diagram of the period
and the lined area for materials to give an overview of the humidity control capacity of a material. The materials of primary
interest in this study were Japanese cedar and porous ceramics. 相似文献
12.
Murakami K Sasaki S Okubo H Takahashi Y Hosoi Y Itabashi M 《Public health nutrition》2007,10(12):1430-1439
OBJECTIVE: Little is known about the relationship of monetary diet costs to dietary intake and obesity, particularly in non-Western populations. This study examined monetary cost of dietary energy in relation to diet quality and body mass index (BMI) among young Japanese women. DESIGN: Dietary intake was assessed by a validated, self-administered, diet history questionnaire. Diet costs were estimated using retail food prices. Monetary cost of dietary energy (Japanese yen 1000 kcal-1) was then calculated. BMI was computed from self-reported body weight and height. SUBJECTS: A total of 3931 female Japanese dietetic students aged 18-20 years. RESULTS: Monetary cost of dietary energy was positively associated with intakes of fruits, vegetables, fish and shellfish, and pulses; however, higher monetary cost of dietary energy was also associated with higher consumption of fat and oil, meat and energy-containing beverages, and lower consumption of cereals (rice, bread and noodles) (all P for trend <0.01). At the nutrient level, monetary cost of dietary energy was positively associated with intakes of dietary fibre and key vitamins and minerals, but also associated positively with intakes of fat, saturated fatty acids, cholesterol and sodium, and negatively with carbohydrate intake (all P for trend <0.0001). After adjustment for possible confounders, monetary cost of dietary energy was quite weakly but significantly negatively associated with BMI (P for trend = 0.0197). CONCLUSIONS: Increasing monetary cost of dietary energy was associated with both favourable and unfavourable dietary intake patterns and a quite small decrease in BMI in young Japanese women. 相似文献
13.
Hoshi H Yagi Y Matsunaga K Ishihara Y Yasuhara T 《Journal of agricultural and food chemistry》2007,55(21):8508-8515
We previously isolated a novel immunomodulatory alpha-(1,4)(1,6)(1,2)- d-glucan-protein complex (MPG-1) from mycelia of Tricholoma matsutake in basidiomycetes. In the present study, we raised a polyclonal antibody by immunizing rabbits with MPG-1 and constructed a sandwich enzyme-linked immunosorbent assay (ELISA) system to examine the distribution of MPG-1 among edible mushrooms and related processed foods. The system detected MPG-1 quantitatively at concentrations of more than 10 ng/mL, with a coefficient of variation of less than 10% by intra-assay and interassay precision. Analysis with the system of chemically modified MPG-1 suggested that the sugar moiety was mainly involved in the detection. The system detected MPG-1 in the extracts of the fruiting bodies of T. matsutake but not in those of 34 other basidiomycete species. Moreover, a significant amount of MPG-1 was detected in the extracts of their cultured mycelia. The antigenic structure of MPG-1 was relatively stable in terms of pH and temperature. MPG-1 was detected in processed foods supplemented with T. matsutake. These results suggest that MPG-1 is distributed predominantly in T. matsutake species and that the ELISA system can detect it in processed foods supplemented with T. matsutake. 相似文献
14.
15.
Patterns of stable carbon and nitrogen isotopes in the baleen of common minke whale Balaenoptera acutorostrata from the western North Pacific 总被引:3,自引:0,他引:3
ABSTRACT: Stable carbon and nitrogen isotope ratios were determined in the baleen plates of 17 common minke whales Balaenoptera acutorostrata from the north-western Pacific Ocean off Japan, as well as prey species (krill Euphausia pacifica , Japanese anchovy Engraulis japonicus and Pacific saury Cololabis saira ) collected in the stomach contents, to investigate the trophic relationship between the minke whales and their prey. A few δ15 N-depleted peaks occurred along the length of baleen plates for 10 males irrespective of stomach content (anchovies and sauries). Similar δ15 N-depleted peaks were also found for one female and two immature individuals. It was likely that these δ15 N-depleted peaks formed in early summer. The stable nitrogen isotope ratio (δ15 N) values in Pacific saury (9.3 ± 1.4‰) did not differ significantly from that in Japanese anchovy (8.8 ± 0.9‰). In contrast, δ15 N in krill (7.2 ± 0.5‰ in July and 8.0 ± 0.2‰ in September) were significantly lower than in the Pacific saury. Thus, these peaks may reflect the dietary change from krill to fishes in the feeding migration of the whales. Growth rate of the baleen plate was estimated to be 129 mm/y, and it appeared that a dietary record of about 1.4 years remained in the baleen plate. For two immature whales, the maximum value of δ15 N occurred at the tip of baleen. This δ15 N enrichment may possibly be useful for discriminating weanlings and older whales. 相似文献
16.
Yoko L. Dupont Dennis M. Hansen Alfredo Valido Jens M. Olesen 《Biological conservation》2004,118(3):301-311
The aim of this study was to investigate effects of introduced honey bees (Apis mellifera) on native pollination interactions of Echium wildpretii ssp. wildpretii in the sub-alpine desert of Tenerife. We selected two study populations, one dominated by honey bees, while the other was visited by many native insects. During peak activity period of insects, nectar was nearly completely depleted in flowers of the first, but not the latter population. Thus, a high abundance of honey bees may have suppressed visitation by native animals due to exploitative competition. Honey bees stayed longer and visited more flowers on the same inflorescence than native bees, thus potentially promoting self-pollination of the plants. Level of seed set and viability was similar in the two study populations. However, we cannot rule out long-term changes in genetic population structure due to changes in gene-flow patterns caused by foraging behaviour of honey bees vs. native flower-visitors. 相似文献
17.
18.
Improvement of the bitter taste of amino acids through the transpeptidation reaction of bacterial gamma-glutamyltranspeptidase. 总被引:1,自引:0,他引:1
Hideyuki Suzuki Yoko Kajimoto Hidehiko Kumagai 《Journal of agricultural and food chemistry》2002,50(2):313-318
The tastes of several bitter amino acids and their gamma-glutamyl derivatives were compared. The bitterness of Phe, Val, Leu, and His was reduced, sourness was produced, and preferences were increased by gamma-glutamylization. Because the effect of gamma-glutamylization of bitter amino acids was most obvious for Phe, which is an atypical bitter amino acid, an enzymatic method for the synthesis of gamma-glutamylphenylalanine (gamma-Glu-Phe) involving bacterial gamma-glutamyltranspeptidase was developed. The optimum reaction conditions were 200 mM Gln, 200 mM Phe, and 0.5 unit/mL GGT, pH 10.4. After 1.5-h of incubation at 37 degrees C, 140 mM gamma-Glu-Phe was obtained, the yield being 70%. gamma-Glu-Phe was purified on a Dowex 1x8 column and then identified by NMR. 相似文献
19.
Yanagita T Wang YM Nagao K Ujino Y Inoue N 《Journal of agricultural and food chemistry》2005,53(24):9629-9633
We investigated the effect of dietary combination of conjugated linoleic acid (CLA) and docosahexaenoic acid (DHA) to attenuate CLA-induced fatty liver in C57BL/6N mice. Mice were fed semisynthetic diets that contained either 6% high linoleic safflower oil (HL-SAF), 4% HL-SAF + 2% CLA, or 3.5% HL-SAF + 2% CLA + 0.5% DHA for 4 weeks. This 4 week feeding of CLA showed hepatic lipid accumulation concomitant with the decrease in adipose tissue weight in mice. However, 0.5% supplementation of DHA to the CLA diet could alleviate fatty liver without decreasing the antiobesity effect of CLA. The CLA diet promoted fatty acid synthesis in the liver, but DHA supplementation significantly attenuated the increase in enzyme activity induced by CLA. On the other hand, serum adipocytokines, leptin and adiponectin, were drastically decreased by CLA feeding, and DHA supplementation did not affect those levels. These results show that DHA supplementation to the CLA diet can attenuate CLA-induced fatty liver through the reduction of hepatic fatty acid synthesis without affecting adipocytokine production in C57BL/6N mice. 相似文献
20.
Hoshi H Yagi Y Iijima H Matsunaga K Ishihara Y Yasuhara T 《Journal of agricultural and food chemistry》2005,53(23):8948-8956
Tricholoma matsutake, a high-class edible mushroom in Japan, has been reported to have excellent biological activities, but difficulty in cultivating the fruit bodies and limited bulk availability have restricted detailed studies. We have developed a method of culturing in tanks, enabling the bulk supply of the mycelia. The preparation (CM6271) exerts modulative effects on the immune competence of mice and rats. In this study, a sodium hydroxide extract of CM6271 was defatted followed by fractionation with a combination of ion exchange chromatography and gel filtration in order to identify the components involved in the expression of the activity, and a single peak fraction (MPG-1) was obtained with reversed phase chromatography. MPG-1 was a glycoprotein (sugar:protein ratio, 94.3:5.7) with a relative molecular mass of 360 kDa, and the sugar moiety contained about 90% glucose. NMR spectra and methylation analysis revealed that the alpha-1,4-linkage was the predominant glucan linkage with alpha-1,6- and alpha-1,2-linkages in the minority. The amino acid composition in the protein moiety was rich in glutamine, alanine, asparagine, leucine, glycine, valine, serine, threonine, isoleucine, and proline. MPG-1 was resistant to degradation with amylase or protease. The oral administration of MPG-1 promoted, in a dose-dependent manner, the recovery of the mouse natural killer cell activity and serum IL-12 level that had been reduced by the loading of restraint stress. The dose of MPG-1 (25 mg/kg) required for the expression of the effect decreases to 1/12 of that of CM6271 (300 mg/kg). Furthermore, MPG-1 formed a complex with TGF-beta1 in vitro, modulating the biological activity of TGF-beta1 by binding to its active form. These results indicate that the mycelium of T. matsutake contains a novel alpha-glucan-protein complex with immunomodulatory activities. 相似文献