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231.
Masaomi Kimura Keigo Noda Tatsuya Makino Hijiri Yamagata Somphasith Douangsavanh Keoduangchai Keokhamphui Hiromasa Hamada Masashi Kiguchi Toshiaki Iida Kazuo Oki 《Paddy and Water Environment》2018,16(3):519-531
Vientiane, Lao PDR, has been subject to extensive and ongoing urbanization plans, including development of natural marshes and residentialization of paddy fields into suburban areas, despite natural marshes playing a vital role in treating wastewater from urban areas. Therefore, it is important to understand the current situation regarding the nutrient balance in these natural wastewater treatment systems to predict future conditions and design appropriate measures against water quality deterioration. However, limited data are available in Vientiane on the hydrological characteristics of water and nutrient runoff that flow into marshes through drainage canals. In this study, we conducted a periodic survey of drainage canals and Mak Hiao River in the wastewater catchment system surrounding Vientiane during the rainy and dry seasons. We monitored the discharge of surface water at 21 observation sites and analyzed water quality of nitrogen, phosphorus, and total organic carbon. These observations revealed that the concentrations of dissolved nitrogen and phosphorus were significantly higher at sites in urban areas, followed by sites in the main river basin and those in agricultural areas. Dissolved nitrogen and phosphorus concentrations varied with runoff discharge, especially in urban and river basin sites, with lower concentrations in the rainy season and higher concentrations in the dry season. On the other hand, we found no significant differences between the rainy and dry seasons in nutrient concentrations in the agricultural basin. Finally, we proposed measures to counteract the deterioration of water quality during dry seasons and simulated the impact of these measures. 相似文献
232.
The IGF‐1/Akt/S6 pathway and expressions of glycolytic myosin heavy chain isoforms are upregulated in chicken skeletal muscle during the first week after hatching 下载免费PDF全文
233.
234.
Haruna Aiso Futoshi Ishiguri Tatsuya Toyoizumi Yuya Takashima Mineaki Aizawa Shinso Yokota 《Journal of Wood Science》2017,63(3):307-312
The objective of this study is to clarify the relationships between tree sizes and the anatomical, chemical, and physical characteristics of reaction wood. Naturally inclined stems or branches in 23 Japanese angiosperms, including 3 tree sizes at adult trees, 7 arbor, 7 subarbor, and 9 shrub species, were used. The presence of a gelatinous (G-) layer, basic density, vessel frequency, and lignin content were examined on the upper and lower sides of each sample. Almost all the species showed a decrease in vessel frequency and lignin content on the upper side, which are typical characteristics of reaction wood in angiosperms. A G-layer was formed in four arbor, one subarbor, and two shrub species. The ratio of the upper and lower sides in vessel frequency and lignin content gradually decreased with an increase in tree size. Based on the results of the principal component and cluster analyses, shrub species were classified into the different groups: from arbor and subarbor groups. These results indicate that the magnitude of alteration in the characteristics due to reaction wood formation of arbor and subarbor might differ from that of shrub, although the characteristics changed by reaction wood formation might be the same in the three tree sizes at adult trees. 相似文献
235.
Various physiological functions of dietary glucosylceramides (GlcCer) have been reported, such as preventing colon cancer
and improving skin barrier function. One potential GlcCer source used as a foodstuff is sea cucumber. In this study, our objective
was to determine the effect of dietary GlcCer prepared from sea cucumber on plasma and liver lipids in cholesterol-fed mice.
ICR mice were fed four different diets (control diet, sea cucumber GlcCer supplemented diet, high cholesterol supplemented
diet, and high cholesterol + sea cucumber GlcCer supplemented diet). Dietary GlcCer decreased total cholesterol significantly
in ICR mice. The mRNA expression of LDL receptor was increased significantly, while the expression of the gene CYP7A1, which is involved in bile acid formation, was decreased significantly compared with the control (diet without cholesterol).
These results suggest that the expression of the cholesterol homeostasis gene in liver is modulated due to the cholesterol
lowering effect of dietary GlcCer. 相似文献
236.
Yoshinori Takahashi Tatsuya Konishi Hiroyuki Enari Heon-sik Lee Won Kyung Lee Young Sun Lee Hyoung Kook Park Shigeru Yamamoto 《Fisheries Science》2011,77(6):1045-1052
Protamine is a basic protein whose sulfate is used in medical applications as a carrier for injectable insulin and as a heparin
antagonist, while its hydrochloride is used as an antibacterial ingredient for some food products. We previously showed that
protamine hydrochloride derived from chum salmon milt inhibited pancreatic lipase and reduced plasma triacylglycerol levels
in an oral fat tolerance test in humans. The present study evaluated the effect of chum protamine hydrochloride on lipid metabolism
in rats. The single oral administration of protamine hydrochloride (500 mg/kg) reduced plasma triacylglycerol levels in a
corn oil tolerance test, and repeated oral administration at a dose of 0, 150, 500, or 1,500 mg/kg with a high fat diet for
7 weeks significantly reduced body weight gain, liver weight, and epididymal adipose tissue, whereas total calorie intakes
were not significantly different. These findings could be caused by the suppression of lipid digestibility leading to a significant
increase in fecal lipid excretion due to the fact that protamine hydrochloride could bind with bile acids to make a complex
that is difficult to digest. Protamine hydrochloride, with a considerable history as food, can be considered to be promising
as an anti-obesity functional food material. 相似文献
237.
Canopy temperature (CT) is often related to potential yield and is a possible yield indicator in breeding programs. However, it is difficult to evaluate genetic variations of CT accurately in large-scale investigations, such as breeding programs, because CT is strongly affected by environmental conditions. In this study, to precisely evaluate these genetic variations, we determined the environmental factors that affect CT measurement and proposed a convenient normalization method to minimize their influence. We measured the CT of CT-high or CT-low cultivars in the field under various conditions. We found that as the sun and shade levels were alternated, the CT changed within seconds; the position in the field also critically affected the CT. However, even under these conditions, the differences between cultivars became clearer if CT was normalized by neighboring lines. Additionally, we revealed that CT measurements between 12:00 and 15:00 maximized the difference between cultivars. Using our normalization technique under the favorable conditions specified can help breeders select high-yield lines using CT in breeding programs. 相似文献
238.
Yoshikuni Kitamura Munetaka Hosokawa Tatsuya Uemachi Susumu Yazawa 《Scientia Horticulturae》2009,122(4):603-609
The mechanism underlying the green colouration of floral organs in phytoplasma-infected hydrangeas was studied. Elucidation of morphological changes of floral organs induced by phytoplasma infection and a comparison of the expression level of genes related to floral organ morphogenesis between phytoplasma-infected and non-infected hydrangea plants was conducted. Sixteen hydrangea (Hydrangea spp.) cultivars were used to study structural changes in floral organs induced by Japanese Hydrangea Phyllody (JHP) phytoplasma infection. The homeotic conversion of sepals to leaves was observed in different number of florets between cultivars, and was observed in 75.8–100% of the decorative florets and 2.7–67.3% of the non-decorative florets of JHP phytoplasma-infected inflorescences. The homeotic conversion of carpels to leaves was observed in 1.2–17.9% of the decorative florets and 0.1–18.9% of the non-decorative florets of infected inflorescences. The expression levels of hydrangea orthologues of class A, B and C genes were suppressed in the infected inflorescences during the developmental stage in which no morphological differences in the internal structure of floral organs have been observed. The contribution of this suppression to homeotic conversion of sepals and carpels to leaves was suggested. 相似文献