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91.
《Journal Of Agricultural & Food Information》2013,14(2):65-81
ABSTRACT Seventeen historically black colleges and universities (HBCUs) had the unique distinction of being designated land-grant institutions in 1890. There is surprisingly little information in the library literature describing the state of automation in academic libraries and even less about the state of automation in the seventeen historically black land-grant universities. The authors designed a questionnaire that would serve as the instrument for a base survey of the state of automation in these libraries. The results of this survey are presented in the following article. 相似文献
92.
针对生产上出现"逆出蚕"这一情况,通过催青实验调查发生逆出蚕的原因及其孵化方式.实验采用碧波×洞庭、春蕾×镇珠2个蚕品种,分别在常温、高温与RH 70%、 RH 80%、 RH 90%组合的6个条件下,进行两段式催青至孵化.通过对孵化率、逆出蚕率的调查,发现影响同一品种逆出蚕的主要原因是湿度,实验还观察到了逆出蚕的孵化方式.这些为今后进一步研究逆出蚕和减少逆出蚕的发生有着积极作用和现实意义. 相似文献
93.
农机推广培训是农机工作的重要环节,但目前依然存在农机购置补贴政策实施滞后、农机产品供货不及时、农机购置补贴范围不宽、农机培训内容单一以及部分农机具定价偏高、适用性不强等问题,为此,提出牢固树立为农民服务的意识、合理分配农机化投入资金、建设高素质农机科技队伍、简化办事程序等工作措施,以促进农机推广培训工作的有效开展。 相似文献
94.
穆奎 《四川畜牧兽医学院学报》2006,4(1):176-181
重庆作为年轻的直辖市,城镇化程度低,是典型的农业大市。因此,没有农业的现代化也没有整个重庆的现代化;没有广大农村地区的全面小康就谈不上整个重庆的全面小康。文章针对重庆特别是农村实际,通过分析重庆农村能否实现全面小康,对整个重庆全面小康的影响,破解农村问题的基本思路;以及针对重庆教育特别是高等农业教育的发展现状、高等农业教育在全面建设农村小康社会中的地位与作用作了进一步的研究。探索出高等农业教育在重庆全面建设农村小康社会中地位特殊、作用重要,发展高等农业教育的任务紧迫。 相似文献
95.
秦廷伟 《四川畜牧兽医学院学报》2006,4(4):138-141
建设社会主义新农村,是我国现代化进程中的重大历史任务,其总的要求是“生产发展、生活宽裕、乡风文明、村容整洁、管理民主”。在这5个要求中,生产发展是社会主义新农村建设的基础和重要任务。所谓生产发展就是要大力发展农村生产力,大幅度增加农民收入。而发展农村生产力,增加农民收入,关键又在于大力推进农业产业化经营。因此,在建设礼会主义新农村的过程中,必须把农业产业化经营作为中心任务,通过调整农业产业结构,选择合适的农业产业化模式,大力推进农业产业化进程,加快建设社会主义新农村。 相似文献
96.
Pouya Dini Kaatje Ducheyne Isabel Lemahieu Wendy Wambacq Hilde Vandaele Peter Daels 《Reproduction in domestic animals》2019,54(7):987-995
Several methods have been proposed to advance the onset of the breeding season in horses. Most of them are based on the exposure to an artificial lighting period combined with hormonal treatments. Mares exposed to an artificial photoperiod are most often housed indoors where the ambient temperature is often higher than the outside temperature. Mares held in barns are also exposed to different daylight intensities than horses kept outside, depending on the architecture. In the current study, we evaluated the impact of ambient temperature, daylight intensity and changes in body condition score (BCS) on the timing of first ovulation after winter anestrus in mares exposed to an artificial photoperiod. Mares (n = 211) were housed in barns with different ambient temperature and daylight exposure but with the same artificial photoperiod exposure (except for a natural photoperiod control group). Artificial photoperiod as well as an increase in BCS over the winter significantly advanced the first spring ovulation. The BCS at the start and end of the anestrus period did not have an effect on the interval to first ovulation and neither did the modest increase in ambient temperature in the barn. However, a higher light intensity during the daytime significantly advanced the first spring ovulation. The results of this study suggest that exposure to more sunlight advances the onset of the breeding season. This effect is likely mediated through the biological effect of short wavelength blue light and its impact on melatonin suppression and biological rhythms. We suggest that greater/direct exposure to the blue light component of daylight improves the response to the artificial photoperiod. The results of the present study can further assist to optimize the conditions that lead to an efficient spring transition of breeding mares. 相似文献
97.
A long-term rangeland monitoring programme needs to employ a field survey technique that is practicable, precise, powerful enough to distinguish change, not prone to worker bias, and able to distinguish real change from operator error arising from staff turnover. These criteria were used to evaluate a widely used grassland sampling technique in South Africa – the nearest-plant (with 200 points) method (NP) – against common alternatives, namely NP excluding forbs (NP-nf), the plant number scale (PNS; a cover-abundance method) and quadrat frequency (QF), using multivariate ordination and permutation tests. Four trained teams surveyed four grasslands using each method. PNS took more than twice as long as the other techniques, which were similarly rapid. Estimates of composition using NP methods were the most precise and PNS was least repeatable, with QF intermediate. Compositional differences between sites were most finely distinguished using NP-nf, followed by NP and QF. PNS was able to detect only marked differences and had the greatest potential for surveyor bias. The NP method, with or without including forbs, is therefore recommended for monitoring the species composition of mesic, dense grassland. Some suggestions for monitoring agencies on how best to use multivariate methods are presented. 相似文献
98.
Previous work has hypothesised that cows in low body condition become lame. We tested this in a prospective longitudinal study. Body condition score (BCS), causes of lameness and milk yield were collected from a 600-cow herd over 44-months. Mixed effect binomial models and a continuous outcome model were used to investigate the associations between lameness, BCS and milk yield. In total, 14,320 risk periods were obtained from 1137 cows. There were 1510 lameness treatments: the most common causes of lameness were sole ulcer (SU) (39%), sole haemorrhage (SH) (13%), digital dermatitis (DD) (10%) and white line disease (WLD) (8%). These varied by year and year quarter. Body condition was scored at 60-day intervals. BCS ranged from 1 to 5 with a mean of 2.5, scores were higher in very early lactation but varied widely throughout lactation; approximately 45% of scores were <2.5. The key finding was that BCS < 2.5 was associated with an increased risk of treatment for lameness in the following 0–2 months and >2–4 months for all causes of lameness and also specifically for SU/WLD lameness. BCS < 2.5 was associated with an increased risk of treatment for SH in the following 0–2 months but not >2–4 months. There was no such association with DD. All lameness, SU/WLD, SH and DD were significantly more likely to occur in cows that had been lame previously, but the effect of BCS was present even when all repeat cases of lameness were excluded from the analysis. Milk yield was significantly higher and fell in the month before treatment in cows lame with SU/WLD but it was not significantly higher for cows that were treated for DD compared with non-lame cows. These findings support the hypothesis that low BCS contributes to the development of horn related claw lameness but not infectious claw diseases in dairy cows. One link between low BCS and lameness is a thin digital cushion which has been proposed as a trigger for claw horn disease. Cows with BCS 2 produced more milk than cows with BCS 2.5, however, this was only approximately 100 kg difference in yield over a 305-day lactation. Given the increased risk of lameness in cows with BCS 2, the direct costs of lameness and the small variability in milk yield by BCS, preventing cows from falling to BCS < 2.5 would improve cow welfare and be economically beneficial. 相似文献
99.
通过大量调查,分析了万州区农业产业化、农村工业化、农村城镇化发展不协调的表现。具体表现在:农业产业化与农村工业化发展不协调,工业化程度偏低,农业产业化程度不高,没有形成规模经济和产业链;农业产业化与农村城镇化发展不协调,影响市场容量的扩大,制约农业自身的发展,制约第三产业发展和农民进入城镇就业步伐,城镇化辐射带动能力弱;农村工业化与农村城镇化发展不协调,城镇对生产要素的集聚功能差,农村工业布局较分散且技术落后,“空城现象”明显;农业产业化、农村工业化、农村城镇化与区域经济发展不协调,区域经济发展水平不高,区域经济结构运行质量不高,区域经济的市场竞争力不强,区域经济的发展环境不优。 相似文献
100.