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1.
Q型烟粉虱为害对不同辣椒品种叶绿素及营养物质的影响   总被引:1,自引:0,他引:1  
为明确辣椒品种对烟粉虱的抗性机制,以不同抗性程度的辣椒为试验材料,研究了其受Q型烟粉虱危害后体内生理指标的变化。结果显示,Q型烟粉虱危害后,辣椒叶绿素和可溶性糖含量均较对照(未接虫)增加,其中抗性品种(苏椒5号、新研988椒王)叶绿素含量增加显著(P0.05);可溶性糖含量以抗性品种增幅最大(P0.05),中抗品种(萧新九号、湘辛三号)次之(P0.05),感虫品种(港上红尖椒、大禹牛角王)的增幅最小。烟粉虱危害后所有参试品种除中抗品种湘辛三号外,其余品种的可溶性蛋白含量均较对照降低;所有参试品种的游离脯氨酸含量均显著降低(P0.05),感虫品种港上红尖椒、大禹牛角王的游离脯氨酸含量均显著高于高抗及中抗品种(P0.05)。因此,辣椒品种对Q型烟粉虱的抗性强弱与叶片叶绿素含量、可溶性糖含量、游离脯氨酸含量有关,而与可溶性蛋白含量无明显相关。  相似文献   
2.
Using an immunocytochemical technique, we have studied in the alpaca brainstem the distribution of immunoreactive structures containing prodynorphin (alpha‐neoendorphin)‐ and pro‐opiomelanocortin (adrenocorticotrophin hormone (18–39) (ACTH), beta‐endorphin (1–27))‐derived peptides. No peptidergic‐immunoreactive cell body was observed. Immunoreactive fibres were widely distributed, although in most of the brainstem nuclei the density of the peptidergic fibres was low or very low. In general, the distribution of the immunoreactive fibres containing the peptides studied was very similar. A close anatomical relationship occurred among the fibres containing alpha‐neoendorphin, ACTH or beta‐endorphin (1–27), suggesting a functional interaction among the three peptides in many of the brainstem nuclei. The number of fibres belonging to the prodynorphin system was higher than that of the pro‐opiomelanocortin system. A moderate/low density of immunoreactive fibres was observed in 65.11% (for alpha‐neoendorphin (1–27)), 18.18% (for ACTH) and 13.95% (for beta‐endorphin) of the brainstem nuclei/tracts. In the alpaca brainstem, a high density of immunoreactive fibres was not observed. The neuroanatomical distribution of the immunoreactive fibres suggests that the peptides studied are involved in auditory, motor, gastric, feeding, vigilance, stress, respiratory and cardiovascular mechanisms, taste response, sleep‐waking cycle and the control of pain transmission.  相似文献   
3.
The present study was conducted to investigate the effects of sodium butyrate (SB) on the physical barrier function, pro‐inflammatory response and possible underlying mechanisms in the distal intestine (DI) of yellow drum when fed a high‐SBM diet. Three iso‐proteic and iso‐lipidic diets were formulated with fish meal (FM, the control), 45% fish meal protein replaced by SBM (SBM) and 45% fish meal protein replaced by SBM but supplemented with 0.15% SB (SBM + SB). Fish were fed twice daily for 10 weeks. Results indicated that SB supplementation significantly increased the specific growth rate (SGR) and feed efficiency ratio (FER) and methionine content of muscle when compared with those of fish fed the SBM diet (p < .05). The morphologic histology results showed that SB dramatically improved the physical barrier structure, characterized as increases of fold height (FH) and muscular thickness (MT) (p < .05). RT‐qPCR data were accordant with morphologic histology results, in which claudin 3, claudin 4 and occludin were increased while claudin 7 and myosin light chain kinase (MLCK) mRNA expression levels were decreased (p < .05). Sodium butyrate also exerted anti‐inflammatory function, which may be attributed to the suppression of nucleus p65 protein expression. Results suggest SB can be incorporated in high‐SBM diets to ameliorate the negative consequences of alternative dietary ingredients on yellow drum physiology.  相似文献   
4.
5.
Abstract

Digltaria eriantha and Chloris gayana were grown under controlled conditions for three months and were treated with a nutrient solution containing 150 mMol NaCl and the following nitrogen sources: 25 or 200 mg/l NH4 +‐N or NO3 ?‐N or no nitrogen. The application of nitrogen was found to stimulate growth, i.e. leaf area and dry mass in both grasses, with a greatest growth response to both NH4 +—N treatments in D. eriantha, and NH4 +‐N and NO3 ?—N treatments in C. gayana. Proline accumulated in both grasses, but this accumulation followed different trends in the two grasses. Soluble sugars (non‐structural) accumulated in the above ground component in D. eriantha, while in C. gayana soluble sugars accumulated predominantly in the roots, possibly as osmotica, or for storage and may thus have been available for regrowth.  相似文献   
6.
pH值胁迫对喜树苗期生长及生理指标的影响   总被引:5,自引:0,他引:5  
对不同pH值胁迫下喜树苗期生长及几种生理指标的影响进行了初步研究。结果表明,不同pH值胁迫对喜树苗期叶片叶绿素、游离脯氨酸含量与SOD活性都有一定的影响,当培养液pH值5.5~6.5时叶片中叶绿素含量最高,SOD活性最强,游离脯氨酸含量最低,喜树幼苗生长较适宜。  相似文献   
7.
Donors and aid agencies are now looking to strategies of pro‐poor economic growth to raise living standards in developing countries. I critically examine how particular conceptualisations of economy and economic development shape the broader context within which pro‐poor growth approaches are implemented by governments and development agencies. While pro‐poor growth may expand a national economy, surplus will be distributed in a community and among individuals according to culturally specific logics. To exemplify this point I discuss the community economy of Bomolo on the remote, rural island of Flores, Indonesia. The Ngadha people of Bomolo are identified by the Indonesian state, religious organisations and development agencies as lacking and in need of economic development. Yet in Bomolo, gambling, although illegal and antithetical to development, is fantastically popular, and large amounts of cash surplus are spent on this popular pastime. I argue for more attention to the issue of surplus – the outcome of pro‐poor growth. In particular, I propose that surplus distribution is a crucial yet underdeveloped component of the growth equation.  相似文献   
8.
垃圾复混肥对玉米生产和土壤性状的影响   总被引:4,自引:0,他引:4  
采用田间小区和盆栽试验方法,研究了利用城市生活垃圾配制的有机-无机复混肥对玉米生产和土壤理化性质的影响。结果表明,当施用垃圾复混肥中的氮量约为商品复合肥纯氮量的一半时,玉米小区经济产量和盆栽生物量分别比不施肥增加29.73%和184..8%,比商品复合肥减产3.51%和18.89%;垃圾复混肥施用量与复合肥纯氮量相等时,分别比不施肥增产38.58%-51.93%和262.0%-239.3%,比商品复合肥增加3.07%—13.00%和3.07%,其增产效果显著。长期施用垃圾复混肥还可以补充和增加土壤有机质和养分,改善土壤理化性状,提高土壤肥力。  相似文献   
9.
水分胁迫对三桠生理特性的影响   总被引:4,自引:0,他引:4  
研究了盆栽三桠在人工控制土壤水分条件下某些生理特性的变化。结果表明,在土壤干旱条件下,三桠叶片自由水锐减,而束缚水含量有所增加,叶绿素含量及净光合速率随着土壤干旱的加重而下降,呼吸消耗增加,光合作用效率降低,蒸腾速率明显下降,在重度干旱时下降达66.6%,水分利用效率有所提高,游离脯氨酸积累较少。这说明三桠对水分胁迫的适应能力较差。  相似文献   
10.
Mandarin fish is a typical carnivorous fish, it can accept artificial diet after domestication, which is significantly essential to optimize its artificial diet. Nevertheless, only few studies were conducted on artificial diet of mandarin fish. Therefore, an 8‐week feeding trial was conducted to evaluate the influence of feeding stimulants on growth performance, feed intake and appetite regulation of mandarin fish. In this trial, six diets were formulated, a basal diet contained 80% of Fish Meal without feeding stimulants, named as Control, 0.4% inosinic acid meal, 0.4% L‐Alanine meal, 3% Yeast meal, 3% a commercial squid extract meal and 0.4% betaine meal were added into the basal diet to make five experimental diets, which were named as IM, AM, YM, SVO and BM respectively. At the end of feeding trial, SVO group showed higher feed intake, up‐regulated mRNA expression of neuropeptide Y (NPY) and down‐regulated mRNA expression of pro‐opiomelanocorticoid (POMC) significantly as compared to control group, which suggested that squid extract improved feed acceptability and promoted appetite in mandarin fish. Similarly, compared to control group, SVO group showed low food conversion ratio, high weight gain and SGR, indicated that squid extract enhanced the growth performance. Our results suggested that the appropriate level of squid extract addition could contribute to optimize artificial diet in mandarin fish.  相似文献   
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