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991.
Fifty-five mg per kg live weight of crystallized Yucca schidigera saponins, corresponding to 26 mg/kg live weight of sapogenins, was given daily intraruminally to two lambs for 11 consecutive days. Neither of the lambs showed any sign of toxicity throughout the experimental period. One lamb was killed 5 h after the last dose and GC-MS analysis of the free and conjugated sapogenin content samples of liver, and of the contents of the rumen, omasum, abomasum, duodenum, jejunum, ileum, colon and rectum, of faecal samples collected before dosing started, and of parts of the administered Yucca saponin were performed. The Yucca material contained mainly sarsasapogenin and smilagenin saponins. Ingested saponins were quickly hydrolysed in the rumen to free sapogenins and, in part, epimerized at C-3 to afford episapogenins. The absorption of free sapogenins appeared to occur in the jejunum. The metabolism of Yucca saponins was identical to that of Narthecium ossifragum saponins, and it is suggested that Yucca saponins could replace N. ossifragum saponins for toxicity studies on the latter plant. 相似文献
992.
Measurement of Cortisol Metabolites in Faeces of Ruminants 总被引:8,自引:0,他引:8
Möstl E Maggs JL Schrötter G Besenfelder U Palme R 《Veterinary research communications》2002,26(2):127-139
Twenty-one metabolites were detected in faecal samples collected after infusion of (14C)cortisol into the jugular vein of sheep, using high-performance liquid chromatography/radiometric analysis plus mass spectrometry. One group of metabolites had molecular weights of between 302 and 308, and another group of 350, which indicates that the substances have a C19O3 or a C21O4 structure. Therefore, an enzyme immunoassay against 5-androstane-3-o1-11,17-dione-17-CMO:BSA was established. Faecal samples were collected from 10 cows immediately after transport and then during a course in which non-invasive diagnostic procedures were being taught (course 1). For comparison, faeces were sampled from another 5 cows that were being used for teaching invasive procedures (course 2). Six cows from a university farm served as controls. In the animals used in course 1, the highest concentrations of cortisol metabolites were measured immediately after transport to the university (median value: 2.2 mol/kg faeces). During the first 5 days at the university, the concentrations decreased to 0.52 mol/kg (median) and remained at this level during the rest of the course. The median concentration in the samples that were taken during course 2 (collected about 2 months after transport) was 0.48 mol/kg. There was no significant difference in the excretion of cortisol metabolites between these cows and the controls. We conclude from these data that, using the enzyme immunoassay against 5-androstane-3-o1-11,17-dione-17-CMO, we were able to detect transport/novel environment stress but not the potential disturbance that cows experience during diagnostic procedures. 相似文献
993.
994.
LJ DEPIAZZI WD ROBERTS CD HAWKINS MA PALMER DR PITMAN NC MCQUADE PD JELINEK DJ DEVEREAUX RJ RIPPON 《Australian veterinary journal》1998,76(1):32-38
Objective To test the hypothesis that ovine footrot associated with a thermostable protease strain of Dichelobacter nodosus undergoes self cure or is sustained as an annually recurring disease, depending on the environment.
Design and procedure Forty Merino sheep from a single blood line were infected with a protease thermostable strain of D nodosus a t each of five sites in Western Australia. Footrot lesions and microscopic evidence of D nodosus were recorded every fortnight for 2.5 years, supplemented by laboratory culture. Rainfall, soil and air temperature, pasture quantity and composition and soil types were also recorded. Flocks that apparently self cured were relocated to a more favourable site for footrot in the final spring season.
Results The maximum prevalence of feet with clinical footrot lesions was 80.6, 1.3, 14.4, 3.8 and 88.1% at the five sites. Severe footrot occurred for three consecutive spring seasons at one site that had clay loam soil and at least 3500 kg/ha total pasture dry matter annually. However, the infection was asymptomatic for up to 10 weeks between outbreaks. D nodosus was isolated from flocks for 2.5 years at only two sites, although there was microscopic evidence of the organism at other sites in the final year. A thermolabile variant (strain U6) of D nodosus was isolated from the two sites where footrot persisted.
Conclusion Depending on time and location, ovine footrot induced by a protease thermostable strain of D nodosus either self cured or persisted as annual outbreaks interspersed with periods of asymptomatic infection. 相似文献
Design and procedure Forty Merino sheep from a single blood line were infected with a protease thermostable strain of D nodosus a t each of five sites in Western Australia. Footrot lesions and microscopic evidence of D nodosus were recorded every fortnight for 2.5 years, supplemented by laboratory culture. Rainfall, soil and air temperature, pasture quantity and composition and soil types were also recorded. Flocks that apparently self cured were relocated to a more favourable site for footrot in the final spring season.
Results The maximum prevalence of feet with clinical footrot lesions was 80.6, 1.3, 14.4, 3.8 and 88.1% at the five sites. Severe footrot occurred for three consecutive spring seasons at one site that had clay loam soil and at least 3500 kg/ha total pasture dry matter annually. However, the infection was asymptomatic for up to 10 weeks between outbreaks. D nodosus was isolated from flocks for 2.5 years at only two sites, although there was microscopic evidence of the organism at other sites in the final year. A thermolabile variant (strain U6) of D nodosus was isolated from the two sites where footrot persisted.
Conclusion Depending on time and location, ovine footrot induced by a protease thermostable strain of D nodosus either self cured or persisted as annual outbreaks interspersed with periods of asymptomatic infection. 相似文献
995.
K. Persson Waller I.G. Colditz P. Flapper H.-F. Seow 《Veterinary research communications》1997,21(2):101-115
Persson Waller, K., Colditz, I.G., Flapper, P. and Seow, H.-F., 1997. Leukocyte and cytokine accumulation in the ovine teat and udder during endotoxin-induced inflammation. Veterinary Research Communications, 21 (2), 101-115The accumulation of leukocytes, ovine serum albumin and the cytokines interleukin-1 (IL-1), tumour necrosis factor- (TNF-), interleukin-8 (IL-8), granulocyte-macrophage colony-stimulating factor (GM-CSF) and interferon- (IFN-) was studied during endotoxin-induced inflammation in lactating and dry ovine udders, and in the teat cisterns of dry ewes after surgical closure of the passage between the teat and udder cisterns. Samples were taken before infusion and hourly up to 10 h after infusion of 0.1, 1 or 10 µg of endotoxin, or infusion of pyrogen-free saline (PFS) as a control. Rectal temperatures were measured.A significant dose- and time-dependent accumulation of leukocytes, mainly neutrophils, was observed in the lactating udders and in the teat cisterns. In the dry udders, the leukocyte accumulation was significant for time but not for dose. Peak numbers of cells were reached at 3-4 h in the dry udders and in the teat cisterns, but not until 10 h after infusion in the lactating udders. The changes in the ovine serum albumin concentrations mostly paralleled changes in leukocyte numbers.A role was indicated for TNF-, IL-8 and GM-CSF, but not for IL-1 and IFN-, during endotoxin-induced inflammation in the ovine udder. Release of TNF-, IL-8 and GM-CSF was most prominent in lactating udders, peaking at 2 or 3 h after infusion, but was also detected in dry udders and teat cisterns. Detectable levels of IL-1 and IFN- were occasionally found in all three groups. 相似文献
996.
997.
随机选取新乡市郊区某养殖场中自然感染寄生虫的40只小尾寒羊,根据试验羊的年龄、体重、营养状况将羊群分为5个组,每组8只羊。具体分组如下:左旋咪唑分2个剂量组,5mg/kg体重组和10mg/kg体重组;丙硫苯咪唑2个剂量组,5mg/kg体重组和10mg/kg体重组。收集粪便,进行寄生虫线虫虫卵与虫体的的检查。试验结果如下:用药后,试验羊只精神好转,症状减轻直至正常;各剂量组药物对各种线虫虫卵及成虫均有明显抑制及杀灭作用,其中,左旋咪唑10mg/kg的剂量组对线虫的驱除效果明显,丙硫苯咪唑也是10mg/kg剂量组对线虫的驱除效果明显。 相似文献
998.
999.
两种绵羊杂种 GDF9 基因和 FecB 基因的多态性及其与产羔数和体重关系的研究 总被引:1,自引:0,他引:1
以绵羊GDF9和FecB基因为候选基因,分别应用PCR-SSCP和PCR-RFLP方法研究了德滩寒杂种羊和陶滩寒杂种羊共63只个体的基因多态性以及基因多态性对产羔数和体重的影响。结果表明,两种基因在两种杂交绵羊群体中各有2种基因型(AA和AB,CC和CD)。在德滩寒杂种羊群体中基因型频率分别为0.09(AA)、0.91(AB)、0.53(CC)、0.47(CD);陶滩寒杂种羊群体中基因型频率分别为0.19(AA)、0.81(AB)、0.58(CC)、0.42(CD)。对德滩寒杂种羊群体研究发现:AA基因型群体平均产羔数为2.50,显著高于AB基因型群体(1.63,P<0.05);CD基因型群体平均产羔数为2.33,显著高于CC基因型群体(1.50,P<0.05)。对陶滩寒杂种羊群体研究发现:AA基因型群体平均产羔数为2.67,显著高于AB基因型群体(1.96,P<0.05);CD基因型群体与CC基因型群体平均产羔数相差不大。这些结果表明:GDF9基因的杂合子与两种杂种绵羊的产羔数之间呈显著负相关;FecB基因杂合子与陶滩寒杂种羊产羔数之间呈显著正相关。FecB基因和GDF9基因对两种绵羊杂种的初生重和断奶重无显著影响。 相似文献
1000.
选4只安装永久性瘤胃瘘管和十二指肠瘘管的中国美利奴(新疆型)细毛羊,采用4×4拉丁方设计,分别添喂腐植酸钠0、2、4、6g/d,以研究其对绵羊瘤胃消化代谢的影响。结果表明:采食后3h,4g/d组和6g/d组的瘤胃pH值分别比对照组降低了1.26%和1.10%(P<0.05)。采食后3h,2g/d组、4g/d组和6g/d组的瘤胃液氨态氮浓度分别比对照组降低了13.75%、18.09%和16.03%(P<0.01)。添加4g/d组显著提高了干物质、有机物的前胃消失量和消失率(P<0.05),添加6g/d组显著提高了干物质的前胃消失量(P<0.05);微生物蛋白到达小肠量有随腐植酸钠添加量的增加而提高的趋势(P>0.05)。添加腐植酸钠有提高羊瘤胃微生物合成的作用,因而可促进瘤胃消化代谢。 相似文献