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791.
大鼠骨肉瘤模型的建立   总被引:3,自引:0,他引:3  
为建立大鼠骨肉瘤动物模型的方法, 用30只6周龄SD大鼠随机分为3组,将大 鼠骨肉瘤细胞系UMR 106分别以105,106, 107个数量注入大鼠股外侧皮下。接种后,每 周观察肿瘤生长情况,测量肿瘤直径,绘制肿 瘤生长曲线,连续5周。第6周取肿瘤病理 材料,常规切片,HE染色,光镜下观察。结果 105个细胞及106个细胞组肿瘤生长情况不 佳;107个细胞组肿瘤发生率达到100%。说 明大鼠骨肉瘤细胞系UMR 106具有较强的 致瘤性,应用该细胞系建立的动物模型为骨 肉瘤综合治疗奠定了动物实验基础。  相似文献   
792.
Thirteen strains of mycobacteria isolated from deer and various species of wild birds were analysed by gas chromatography (GG) for cellular fatty acids and by thin-layer chromatography (TLG) for polar lipids. These strains were compared to reference strains of Mycobacterium avium, M. para tuberculosis and M. mal-moense. All the examined strains exhibited a generally similar fatty acid pattern characterized by relatively large amounts of hexadenca-noate (16:0), octadecenoate (18:1), octadecanoate (18:0) and 10-me-thyl-octadecanoate (tuberculostearic acid, 10-Me-18:0). Several additional acids were also generally present but in smaller amounts. By means of small but distinct differences in fatty acid composition, the wild animal isolates could be distinguished from both M. paratuber-culosis and M. malmoense but not from M. avium.The TLG polar lipid patterns on the other hand separated the wild animal isolates into 2 distinct groups of complex and simple polar lipid composition which corresponded to the morphologically smooth and rough types, respectively. The complex patterns of the smooth strains were comparable to those of the M. avium serovars whereas both the rough wild animal isolates and all the M. paratuber-culosis strains showed a simple pattern of polar lipids.Both fatty acid profiles and TLG polar lipid patterns support allocation of the wild animal isolates to the MAIS complex. Moreover, the 2 chemical techniques, particularly the GC procedure, are very useful for a more rapid and precise identification of the slow-growing wild animal mycobacterial isolates which have hitherto been characterized on basis of vague criteria.  相似文献   
793.
Abstract. This article examines some of the factors that influence the relative risk of Escherichia coli pollution of surface waters from grazing animals compared to cattle slurry application. Drainage water from pipe‐drained plots grazed with sheep (16 sheep + lambs per hectare) from 29 May to 17 July 2002 had average E. coli counts of 11 c.f.u. mL?1 or 0.4% of estimated E. coli inputs over the grazing period. Drainage water from plots on the same site treated with cattle slurry (36 m3ha?1 on 29 May 2002) had lower average E. coli counts of 5 c.f.u. mL?1 or 0.03% of estimated faecal input. Sheep (16 lambs per hectare) grazing under cooler, moister conditions from 24 September to 3 December 2001 gave drainage water with much higher average E. coli counts of 282 c.f.u. mL?1 or 8.2% of estimated input, which is more than twice the average E. coli counts previously reported under such conditions (Vinten et al. 2002 Soil Use and Management 18, 1–9). Laboratory studies of runoff from soil slabs after slurry application showed that the mobility of E. coli in surface soil decreased with time, suggesting that increased attachment to soil or migration to ‘immobile’ water also provides at least part of the physical explanation for the relatively higher risk of pollution from grazing animals compared with slurry. Sampling for E. coli in field drainflow and in streamwater during a storm event in the predominantly dairy Cessnock Water catchment, Ayrshire, Scotland supported the hypothesis that E. coli transport is linked to grazing animals. For a 7‐mm rainfall event, roughly 14% of the estimated daily input from grazing livestock was transported to the river, even though little slurry spreading had occurred in the catchment in the previous month. Spot sampling of field drains in grazed fields and silage fields in the same catchment also showed that grazing animals were the principal source of E. coli and faecal streptococci.  相似文献   
794.
Contents: The periodic acid-Schiff (PAS) reactive materials of epididymal and ejaculated spermatozoa have been studied in Friesian bulls, buffalo bulls, rams and camels. In the four species, the cytoplasmic droplets displayed strong PAS reaction which did not appear to change markedly during epididymal transit. Only in ram a slight reduction was noted in cauda epididymal and vas deferens spermatozoa. In Friesian bulls, the acrosomes of epididymal spermatozoa exhibited moderate PAS reaction which increased on passage to the vas deferens and after ejaculation. In the buffalo the reaction increased in cauda epididymal and vas deferens spermatozoa but returned again to mderate on ejaculation. In the camel the acrosomes of caput spermatozoa showed strong reaction which was sharply reduced on passage beyond. Meanwhile in rams the acrosomes of spermatozoa obtained from any level of the genital tract exhibited weak PAS reaction. The postnuclear reagions, middle pieces and tails of bull, buffalo, ram and camel spermatozoa showed varying degrees of PAS reaction. The pattern of change during transit of spermatozoa differed from species to another which might be related to the nature of maturational processes. Inhalt: PAS-reaktive Polysaccharide in Saugetierspermien wahrend der Passage durch den Nebenhoden PAS-positive Reaktionen von Nebenhodenspermien und ejakulierten Spermien wurden an Friesian- und Büffelbullen, Schafböcken und Kamelhengsten untersucht. In allen 4 Spezies zeigten die Cytoplasmatröpfchen starke Reaktion, die sich wahrend der Nebenhodenpassage nicht merklich veränderte. Nur beim Schafbock wurde eine geringfügige schwächere Reaktion bei Spermien aus dem Nebenhodenschwanz und dem Vas deferens beobachtet. Bei Friesianbullen zeigte das Akrosom der Nebenhodenspermien eine mittelstarke PAS-Reaktion, die nach Passage durch den Samenleiter und nach der Ejakulation weiter verstarkt war. Beim Büffel war die Reaktion in der Cauda und Vas deferens verstarkt, in ejakulierten Spermien aber wieder schwächer. Beim Kamel war das Akrosom der Caput-Spermien stark positiv, bei der nachfolgenden Passage nahm die Reaktion deutlich ab. Das Akrosom der Schafspermien war in allen Organabschnit-ten nur schwach angefärbt. Bei allen vier untersuchten Spezies zeigten die anderen Spermienbereiche (postnukleare Region, Mittelstück, Schwanz) sehr unterschiedliche Reaktionen. Die Veränderungen während er Nebenhodenpassage waren zwischen den Spezies unterschiedlich und vermutlich abhängzg von Unterschieden in den Reifungsprozessen.  相似文献   
795.
The recycling of sewage sludge or biosolids to grassland is strategically important in the European Union (EU) and its use is tightly regulated to control the risk of pathogen transfer to animals and the food chain. Sewage sludges not only contain valuable concentrations of beneficial nutrients, but also elevated concentrations of potentially toxic metals (PTM) compared with average background concentrations in the soil. The EC and UK regulations refer to six PTM, Cd, Pb, Cu, Zn, Ni and Hg, with provisional regulations for Cr, that have to be controlled to prevent detrimental effects on soil and animal health. Despite these regulations, there is still a danger that grazing animals may ingest elevated concentrations of PTM. Biosolids may adhere to herbage after the surface application of sewage sludge to grassland. The repeated surface application of sewage sludge to grassland can lead to elevated concentrations of PTM at the soil surface that may be ingested, together with soil and herbage, by grazing ruminants. This may lead to accumulation of Cd or Pb in liver or kidney. The risk to the human food chain is considered to be low, but the impact on the environment is still unknown. There is little information, for example, on the amount of soil and PTMs that may become incorporated into conserved grass. At present EU and UK legislation and voluntary codes of practice have been developed to protect animal from pathogens in sewage sludge and to minimize any potential risks from accumulation of PTM. The background and implementation of the legislation are examined in this review, and the source and mechanisms of accumulation of PTM by the grazing animal are evaluated.  相似文献   
796.
End-tidal monitors for measuring carbon dioxide (CO2) have become widely available for clinical use in the last two decades. This non-invasive technology has been previously evaluated in anesthetized veterinary patients, but its accuracy has not been assessed in critical patients. We investigated the usefulness and limits of end-tidal CO2 monitoring in two populations of critical small animal patients: spontaneously breathing dogs and mechanically ventilated patients with healthy and damaged lungs. In analyzing samples from 43 spontaneously breathing dogs and 34 ventilated patients (28 dogs and six cats), the end-tidal CO2 was generally lower than pCO2. The predictive value for hypoventilation was excellent in both populations (100%). The linear correlation of the end-tidal CO2 and arterial pCO2 in non-panting dogs with healthy lungs was 0.84 (p<0.0001), and the 95% confidence interval (CI) of the difference was ± 3.2 mm Hg. However, the measures were uncorrelated in panting dogs (r=0.37, p=0.27), and the 95% CI was ± 13.37 mm Hg. Furthermore, where multiple samples could be obtained in individual patients, the r values and differences of end-tidal compared to arterial pCO2 varied unpredictably. These variations did not appear to be predicted by patient factors such as lung disease. We conclude that the end-tidal CO2 monitor is clinically useful for detecting hypoventilation and monitoring apnea, but it should be supplemented with arterial pCO2 determinations if it is important to obtain accurate pCO2 measures.  相似文献   
797.
4型菌毛、毒素及蛋白酶在动物源气单胞菌的检测   总被引:1,自引:0,他引:1  
将来源于鱼、猪、犬等9种动物的18株气单胞菌分离株通过AD(氨苄青霉素-糊精)培养基纯化。另以大肠杆菌束状菌毛相关(bfp-related)基因的PCR引物对EB1(GATTGAATCTGCAATGGTGC)—EB2(GGATTACTGTCCTCACATAT)扩增,用digoxingenin-11-dUTP标记,构建核酸探针,作斑点杂交试验,用以检测上述气单胞菌菌株的4型菌毛,同时以溶血试验检测其毒素,用脱脂奶溶蛋白圈试验检测其蛋白酶。结果显示,在18个菌株中,4型菌毛、毒素和蛋白酶均为阳性者为10株(55.6%);3项指标均无肯定的阳性结果者4株,两者合计共14株,占检测总数约80%(14/18),提示这3种毒力因子存在较高的相关性。所有鱼源株(5株)三项指标皆为阳性;4株猪分离株三项指标均为阳性者占一半;其它动物分离株检测结果无明显规律性  相似文献   
798.
谷氧还蛋白和硫氧还蛋白分别是动物机体抗氧化酶系统和抗氧化非酶系统的重要成员,具有多种生物学作用,在调节机体的氧化还原反应、抑制细胞凋亡和肠道保护方面起着重要作用.本文结合谷氧还蛋白和硫氧还蛋白的结构与功能、抗氧化机制及抑制细胞凋亡的最新研究近况,就谷氧还蛋白和硫氧还蛋白对动物抗氧化应激生物学效应的研究进行了综述.  相似文献   
799.
植物精油在动物营养中的研究进展   总被引:2,自引:0,他引:2  
介绍了植物精油的安全性评价、理化性质、来源及组成,阐述了植物精油在单胃动物和反刍动物营养上的研究进展.  相似文献   
800.
本文系统地介绍了微量元素对家畜繁殖性能影响的研究进展。主要论述了微量元素不足或过剩对猪、牛和羊的发情、配种、受胎、胚胎发育和存活以及仔畜初生重和断奶重的影响,以及在畜牧生产中满足种畜各种微量元素营养需要的必要性。  相似文献   
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