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921.
The concentrations of copper, zinc and molybdenum were measured in the liver of goats from western and south-eastern Norway. The mean copper concentrations in the liver of goats from these two districts were 23±19 µg Cu/g and 59±31 µg Cu/g wet weight, respectively. As for zinc and molybdenum, no difference was found between the two groups of animals. No correlations were detected between copper and zinc, zinc and molybdenum, or copper and molybdenum. The copper levels in Norwegian goat liver are considerably lower than in sheep liver, and the ranges are significantly more narrow. The concentrations of molybdenum in goat liver are at the same levels as in sheep and swine, while the levels of zinc are somewhat lower. 相似文献
922.
The solubility of Cu and Zn binding proteins was studied in liver samples from clinically healthy and chronic copper poisoned sheep (CCP). Homogenized liver was divided by ultracentrifugation into cytosol and pellet. The cytosol was gelfiltrated, Cu and Zn contents were determined in the eluates as well as in the pellet. Liver homogenate, cytosol and pellet were treated with 2-mercaptoethanol (ME). The resulting clear solutions were fractionated by gel filtration followed by determination of the contents of the two metals in the eluates.In CCP sheep the solubility of Cu containing proteins from the liver homogenate and pellet increased after incubation with ME.The results suggest that in CCP sheep a considerable amount of Cu containing proteins are present in an insoluble form, which to some extent is resolubilized by ME. 相似文献
923.
Dynamics of the Cumulation of Iron, Copper and Sodium During Development to Maturity of Soybean Seed
The dynamics of the cumulation of iron, copper and sodium with four genotypes of soybean cultivated in the same topographical and agrotechnical conditions during three years was followed. Sampling was done in weekly intervals until complete maturity of seed. It was found out that the most intense cumulation took place during the seed development stages III and IV at the time of mostly expressed metabolic activity of the seed. The absolute values of the contents were increasing along with seed maturing and maximums were reached by the end of the stage IV or rather by the beginning of the seed development stage V. Although the dynamics of cumulation regardless of the year of investigation was equal with all the genotypes the analysis of the impact of climatic factors showed that higher precipitation at the period of seed development along with moderate air temperature affected mineral cumulation. Similarly, the highest contents of iron, copper and sodium observed with the genotypes Srecka and Maksimirka point out that the cumulation of the investigated minerals in soybean seed is affected by genetic particularity. 相似文献
924.
The ash, silica and certain important micronutrients were estimated in conventional and unconventional feed and fodder resources available in Southern India. Commonly used dry roughages, such as paddy straw, ragi straw, maize kadbi/stalk, jowar kadbi/stalk, bajra stalk and wheat straw, were high in ash (9.9% +/- 0.77%) and silica (6.4% +/- 0.65%) and low in most of the other micronutrients, except iron, with paddy straw containing most silica (>9%). Cultivated non-leguminous (maize, jowar) and improved green crops (hybrid napier, guinea, green panic, NB-21, CO-1) were also high in ash (10.5% +/- 0.60% and 12.5% +/- 0.51%) but were moderate sources of P, Mg and Cu and good sources of Zn (98 +/- 13.8 ppm and 55 +/- 6.7 ppm). Leguminous green fodders (stylosanthus, lucerne, cow pea, soyabean) were excellent sources of Ca (1.9% +/- 0.16%), Mg (0.40% +/- 0.05%), Cu (30 +/- 5.2 ppm), Zn (121 +/- 14.7 ppm) and Fe (1234 +/- 166 ppm) and moderate sources of P. Mixed local grasses and weeds were high in silica (6.9% +/- 1.00%) but were good sources of Cu, Zn and Fe. Cereal grains (maize, wheat, rice, ragi) were low in ash (2.9% +/- 0.33%) and were relatively poor sources of Ca (0.22% +/- 0.03%), Mg (0.19% +/- 0.03%) and Cu (13 +/- 3.1 ppm). Pulses were low to medium sources of most minerals and good sources of Fe (1230 +/- 293 ppm). Oil seed cake/extractions (groundnut cake, cotton seed cake, soyabean meal, sunflower cake, safflower cake) and cereal by-products (rice polish, rice bran, wheat bran) were excellent sources of P (1.1% +/- 0.47% and 2.3% +/- 0.19%) and good sources of Zn (65 +/- 3.9 ppm and 66 +/- 10.7 ppm) and Fe (938 +/- 130 ppm and 662 +/- 126 ppm). Among the unconventional feeds screened, orange peel, sunflower heads, meat meal, rubber seed cake, spirulina algae and sea weeds contained plentiful Ca, Zn and Fe: tree leaves/top feeds (mulberry, erythrina, glyricidia, banana, subabul, groundnut haulms) were excellent sources of Ca (1.5% +/- 0.13%), Zn (120 +/- 22.9 ppm) and Fe (1033 +/- 133 ppm) but relatively poor sources of P. Soyabean husk, cocoa seed husk, rubber seed cake and meat meal were moderate to good sources of P (1.0% and 0.33%). The high Zn and Fe values of most feeds/fodders were probably due to soil contamination. This account of the micronutrient content of feed/fodder resources should help in strategic supplementation intended to alleviate local deficiencies. 相似文献
925.
Chartier C Etter E Hoste H Pors I Koch C Dellac B 《Veterinary research communications》2000,24(6):389-399
The spread of benzimidazole-resistant nematodes in dairy goat farms is of a great concern as probably more than 70% of the flocks are involved. As there are very few other anthelmintic options during the lactating period, we have evaluated the efficacy of copper oxide needles (CON, Copinox, Bayer, UK) in both experimental and natural infections in goats. The curative effect of CON (2–4 g) on existing worm burdens was assessed in goats experimentally infected with Teladorsagia circumcincta, Haemonchus contortus and Trichostrongylus colubriformis, compared to controls. The preventive effect of CON (4 g) on worm establishment was monitored for 2 months in animals experimentally infected with H. contortus and for 3 months in naturally infected animals on a farm exhibiting predominant infections with T. circumcincta and Oesophagostomum venulosum. In both experimental and natural conditions, the efficacy of CON was nil against Teladorsagia, Trichostrongylus and Oesophagostomum infections. In contrast, the efficacy of CON against Haemonchus was clearly established in reducing the worm burden (75%) as well as in lowering the egg output (37–95%) in relation to the establishment of new infections over several weeks. Copper oxide needles may represent an alternative to conventional anthelmintics in the control of Haemonchus infection in some goat farms. 相似文献
926.
927.
180只1日龄艾维茵肉鸡健雏随机分为3组,分别饲喂对照(每千克日粮含铜11.97mg)和铜中毒(每千克日粮舍铜650mg,铜中毒Ⅰ组;每千克日粮含铜850mg,铜中毒Ⅱ组)日粮6周,以流式细胞术和酸性-α-醋酸萘酯酶(ANAE)染色的方法观测外周血T-淋巴细胞的动态变化。2个铜中毒组1~6周龄外周血T-淋巴细胞的ANAE阳性率均显著低于对照组(P〈0.05或P〈0.01),同时2个铜中毒组间比较也呈显著差异(P〈0.05或P〈0.01)。与对照组比较,2个铜中毒组2~6周龄CD4^+T淋巴细胞数量均显著降低(P〈0.05或P〈0.01),CD8^+T淋巴细胞数量变化不明显(P〉0.05),CD4^+/CD8^+比值降低(P〈0.05)。结果表明,铜中毒可抑制T-淋巴细胞的生成,降低其在外周血中的数量。 相似文献
928.
补铜对奶牛血浆铜含量和铜蓝蛋白活性及其相关性的影响 总被引:3,自引:0,他引:3
本试验选取了大庆地区某奶牛群11头泌乳奶牛,检测补铜前后奶牛血浆铜含量和铜蓝蛋白(CP)活性的变化,同时分析了两者相关性。结果表明:补铜前血浆铜在10.93 μmol/L以下者占被检牛数的54.55%(6/11),其血浆CP活性降低,两者呈现中度相关性(R2=0.53);补铜后血浆铜含量与CP活性均极显著增高(P<0.01),血浆铜含量达到正常范围,两者呈现低相关性(R2=0.12)。〖JP〗结论:该奶牛场泌乳奶牛群中存在低铜血症病牛,血浆铜蓝蛋白可以作为奶牛低铜血症的一项检测指标。 相似文献
929.
日粮添加高铜对产蛋鸡生产性能和脂质代谢的影响 总被引:3,自引:0,他引:3
试验研究饲粮中添加铜对产蛋鸡生产性能,脂质代谢和组织铜含量的影响。试验共分4个处理,分别在基础饲粮中添加0、100、250、300mg/kg铜,80只360日龄的新罗曼蛋鸡随机分到4个处理中,每个处理5个重复,每个重复4只鸡,试验期28d。结果表明:添加高铜对各阶段产蛋鸡的采食量,产蛋率,蛋重无显著影响(P>0.05);但与对照组相比,添加高铜降低了第14、21、28天鸡蛋中每克蛋黄的胆固醇(TC)含量(P<0.05)和第21天血清中甘油三酯(TG),极低密度脂蛋白胆固醇(VLDL-C)含量(P<0.05)以及第28天肝脏中谷胱苷肽(GSH)的含量(P<0.05)。添加300mg/kg的铜增加了肝脏中铜的沉积(P<0.05),而对蛋黄中铜的含量无影响。本研究表明添加铜能够降低蛋黄中的TC含量,而对蛋鸡的生产性能和蛋黄中铜的含量无显著影响。 相似文献
930.
Eduardo Hidalgo Roy Bateman Ulrike Krauss Martijn ten Hoopen Adolfo Martínez 《European journal of plant pathology / European Foundation for Plant Pathology》2003,109(9):953-961
This paper describes a factorial trial designed to investigate the delivery systems of fungal biological agents (Clonostachys rosea), applied as single strain or as strain mixture, in comparison with copper hydroxide as a chemical standard against Moniliophthora roreri in cocoa. Application techniques compared were motorised mistblowers fitted with rotary atomisers and hydraulic sprayers fitted with cone nozzles giving a narrow angle of spray. The third factor was the presence or absence of an emulsifiable rape-seed adjuvant oil in the tank mixture. Copper fungicide was the best agent for moniliasis control and resulted in the highest yield. Both the mycofungicides reduced sporulation of the pathogen. Net reduction of inoculum was best for the hydraulic sprayer-applied copper fungicide and the motorised mistblower-applied single-strain biocontrol agent. Overall, directional hydraulic sprays were found to be somewhat superior to the motorised mistblower technique, with its dissipated cone of spray. Addition of the adjuvant oil was the least important of the factors, but efficacy depended on the agent used, with a significant enhancement in the efficacy of copper with oil but a detrimental effect on C. rosea. 相似文献