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91.
Strategies to modulate the intestinal microbiota and their effects on nutrient utilization,performance, and health of poultry 总被引:1,自引:0,他引:1
Poultry is widely produced and consumed meat global y. Its demand is expected to continue increasing to meet the animal protein requirement for ever-increasing human population. Thus, the chal enge that poultry scientists and industry face are to produce sufficient amount of poultry meat in the most efficient way. In the past, using antibiotics to promote the growth of poultry and manage gut microbiota was a norm. However, due to concerns over potential fatalistic impacts on food animals and indirectly to humans, their use as feed additives are banned or regulated in several jurisdictions. In this changed context, several alternative strategies have been proposed with some success that mimics the functions of antibiotics as growth promoters and modulate gut microbiota for their beneficial roles. These include the use of probiotics, prebiotics, organic acids, and exogenous enzyme, among others. Gut microbiota and their metabolic products improve nutrient digestion, absorption, metabolism, and overal health and growth performance of poultry. This paper reviews the available information on the effect of feed additives used to modulate intestinal microbiota of poultry and their effects on overal health and growth performance. Understanding these functions and interactions wil help to develop new dietary and managerial strategies that wil ultimately lead to enhanced feed utilization and improved growth performance of poultry. This review wil help future researchers and industry to identify alternative feed ingredients having properties like prebiotics, probiotics, organic acids, and exogenous enzymes. 相似文献
92.
The antifungal activity of three flavones and one flavanone and of different mixtures of these flavonoids was investigated on malt extract agar against four fungi usually occurring on grain. As pure substances the unsubstituted flavone and flavanone showed higher activity than the hydroxylated flavones. Mixtures containing flavone and 7-hydroxyflavon or flavone, flavanone and flavonol caused higher inhibition of fungal growth than the remaining ones. 相似文献
93.
Kumar N Jadhao SB Chandan NK Kumar K Jha AK Bhushan S Kumar S Rana RS 《Fish physiology and biochemistry》2012,38(4):989-1000
A five-week experiment was conducted to delineate stress-mitigating effects of three different methyl donors in Labeo rohita fingerlings subjected to endosulfan toxicity. Four iso-nitrogenous and iso-caloric feed were prepared with and without supplementation of methyl donors. The feed were basal or control diet (i.e., without methyl donor supplementation), feed supplemented with choline, feed supplemented with betaine and feed supplemented with lecithin. Two hundred and twenty-five fishes were distributed randomly in five treatment groups each with three replicates. The experimental setup were normal water (without endosulfan) and fed with control diet (control group), endosulfan-treated water and fed with control diet (T?), endosulfan-treated water and fed with choline supplemented feed (T?), endosulfan-treated water and fed with betaine supplemented feed (T?) and endosulfan-treated water and fed with lecithin-supplemented feed (T?). The level of endosulfan in endosulfan treated water was maintained at the level of 1/10 of LC??, that is, 0.2 ppb. During the experiment, growth performances, metabolic enzyme activity and histological examination were done to assess the effect of treatments. The growth performance (percentage weight gain, feed conversion ratio, specific growth rate and protein efficiency ratio) and nutrient digestibility were significantly different (P<0.01) in lecithin, betaine and choline fed group when compared to endosulfan-exposed group fed with basal diet. The liver LDH and MDH activity were significantly (P<0.01) improved in the groups fed with methyl donor supplemented diet. The liver AST and ALT, brain AChE and muscle ALT did not change with supplementation in the diet, but muscle ALT and G6PDH significantly (P<0.01) changed with supplementation. The gill and liver ATPase and intestinal ALP were significantly (P<0.01) noticeably changed in supplemented group. After endosulfan exposure, histopathology alter like slight large vacuolation in hepatocyte and lipoid vacuole were observed and with supplementation normal appearance of liver were observed. The chromosome aberration (karyotype) was observed in endosulfan-exposed group. The result obtained in present study concluded that inclusion of methyl donors, particularly lecithin and betaine, in feed as nutritional supplements has a potential stress-mitigating effect in L. rohita fingerlings. 相似文献
94.
Increasing severity of high temperature worldwide presents an alarming threat to the humankind. As evident by massive yield losses in various food crops, the escalating adverse impacts of heat stress (HS) are putting the global food as well as nutritional security at great risk. Intrinsically, plants respond to high temperature stress by triggering a cascade of events and adapt by switching on numerous stress‐responsive genes. However, the complex and poorly understood mechanism of heat tolerance (HT), limited access to the precise phenotyping techniques, and above all, the substantial G × E effects offer major bottlenecks to the progress of breeding for improving HT. Therefore, focus should be given to assess the crop diversity, and targeting the adaptive/morpho‐physiological traits while making selections. Equally important is the rapid and precise introgression of the HT‐related gene(s)/QTLs to the heat‐susceptible cultivars to recover the genotypes with enhanced HT. Therefore, the progressive tailoring of the heat‐tolerant genotypes demands a rational integration of molecular breeding, functional genomics and transgenic technologies reinforced with the next‐generation phenomics facilities. 相似文献
95.
Although a variety of rainfall-runoff models are available, selection of a suitable rainfall-runoff model for a given watershed
is essential to ensure efficient planning and management of watersheds. Such studies are relatively limited in developing
nations, including India. In this study, rainfall-runoff modeling was carried out using HEC-HMS and WEPP hydrologic models,
and remote sensing and GIS (geographical information system) techniques in the Upper Baitarani River basin of Eastern India
using daily monsoon season (June–October) rainfall and the corresponding streamflow data of 6 years (1999–2005). Other input
data such as soil map, land use/land cover map, and slope map were prepared using remote sensing and GIS techniques. The modeling
results revealed that both the models under predict streamflow for 1999, 2002, 2004, and 2005 and over predict for 2001 and
2003, whereas HEC-HMS under predicts and WEPP over predicts streamflow for the year 2000. The percent deviation of total runoff
volume simulated by HEC-HMS ranges between −2.55 and 31%, while it varies from −13.96 to 13.05% for the WEPP model which suggests
that the WEPP model simulates annual flow volumes more accurately than the HEC-HMS model for most years. However, the lower
values of root mean square error (RMSE) and RMSE-observation standard deviation ratio coupled with the higher values of Nash–Sutcliffe
efficiency, percent deviation and coefficient of determination for HEC-HMS during calibration and validation periods indicated
that the streamflow simulated by HEC-HMS is more reliable than that simulated by WEPP. Overall, it is concluded that the HEC-HMS
model is superior to the WEPP model for simulating daily streamflow in the Baitarani River basin of Eastern India. 相似文献
96.
97.
Effect of contrasting tillage and cropping systems on soil aggregation,carbon pools and aggregate‐associated carbon in rainfed Vertisols 下载免费PDF全文
98.
The methanol extract of the dried leaves of Abies webbiana was evaluated for antimicrobial activity. The methanol extract showed a broad spectrum of antibacterial activity. 相似文献
99.
Hua Thai Nhan Tran Xuan Minh Hon Jung Liew Tran Thi Thanh Hien Rajesh Jha 《Aquaculture Nutrition》2019,25(3):662-668
This study was performed to evaluate the effect of dietary natural carotenoid sources on skin colour enhancement of false clownfish Amphiprion ocellaris. The juvenile fish (initial body wt. 0.30 g) were fed with four experimental diets including (a) commercial feed (reference diet), (b) moist feed, (c) sweet potato (potato diet) and (d) dried gut weed Enteromorpha sp. (gut weed diet). Sweet potato and gut weed were used to boost up β‐carotene levels in the diets. There was no significant difference in final weight (0.51 ± 0.02 – 0.61 ± 0.01 g) and length (2.80 ± 0.02 cm) of fishes among treatments (p > 0.05) after 8 weeks. The survival rate of the fish in all dietary treatment was greater than 89%. Principal component analysis results showed that fish fed potato and gut weed diets performed brighter colour in skin with more orangeness, body and accumulated β‐carotene levels were higher than those fish fed with reference diet. Indicator a* value for the redness of fish fed potato diet (16.18 ± 0.59) and gut weed (14.36 ± 2.14) was also higher than fish fed reference diet (10.92 ± 0.82). The result of this study provided key information for developing dietary colour enhancement of ornamental fish by using cost‐effective feed ingredients (potato and gut weed) as natural supplemental carotenoid sources. 相似文献
100.
Cusser Sarah Grando Carolina Zucchi Maria Imaculada López-Uribe Margarita M. Pope Nathaniel S. Ballare Kimberly Luna-Lucena Danielle Almeida Eduardo A. B. Neff John L. Young Kenneth Jha Shalene 《Landscape Ecology》2019,34(7):1825-1836
Landscape Ecology - Bees are the most important pollinators of crops worldwide. For most bees, patches of semi-natural habitat within or adjacent to crops can provide important nesting and food... 相似文献