全文获取类型
收费全文 | 82篇 |
免费 | 17篇 |
专业分类
林业 | 9篇 |
农学 | 4篇 |
基础科学 | 1篇 |
8篇 | |
综合类 | 3篇 |
农作物 | 6篇 |
水产渔业 | 18篇 |
畜牧兽医 | 48篇 |
植物保护 | 2篇 |
出版年
2021年 | 4篇 |
2020年 | 2篇 |
2019年 | 5篇 |
2018年 | 2篇 |
2017年 | 7篇 |
2016年 | 7篇 |
2015年 | 8篇 |
2014年 | 8篇 |
2013年 | 9篇 |
2012年 | 4篇 |
2011年 | 3篇 |
2010年 | 3篇 |
2009年 | 7篇 |
2007年 | 2篇 |
2006年 | 4篇 |
2005年 | 1篇 |
2002年 | 4篇 |
2000年 | 3篇 |
1999年 | 1篇 |
1998年 | 2篇 |
1997年 | 2篇 |
1996年 | 3篇 |
1995年 | 2篇 |
1994年 | 2篇 |
1992年 | 1篇 |
1991年 | 1篇 |
1990年 | 1篇 |
1988年 | 1篇 |
排序方式: 共有99条查询结果,搜索用时 15 毫秒
1.
SUMMARY Clinical signs of proliferative haemorrhagic enteropathy (PHE) including anaemia, dysentery and sudden death were observed in finisher pigs and young breeding stock on 2 farms. On farm A, PHE occurred 12 months after repopulation of the farm. Other outbreaks of PHE occurred after the withdrawal of therapeutic concentrations of in-feed antibacterial agents (farm A), or after monensin sodium (100 g/t) replaced olaquindox (100 g/t) in feed (farm B). The outbreaks, the possible sources of contamination and the role of antibacterial feed additives in the treatment and control of PHE are described. 相似文献
2.
This paper explores the influence over time of past policies on people’s attitudes towards the use of forestland in Bangladesh.
The discourses of the attitudes of people were captured from the observed social tradition towards forest resources. Forests
were reserved systematically and solely through the Forest Department. The conservation processes were not participatory,
and rights and tenure were strictly controlled. People were socially excluded and alienated from the forest, and the socio-political
factors stimulated negative attitudes among people. Forests were considered to be government property, and therefore managing
forests was the responsibility of the government. People only used forest resources to meet their own requirements, either
with formal permission or illegally. This situation continued even after the independence of Bangladesh in 1971. As a result,
the forests of Bangladesh have been degraded heavily in recent decades. 相似文献
3.
4.
Badrul Hasan Kamrul Islam Murshidul Ahsan Zakir Hossain Mahmudur Rashid Bibhas Talukder Kabir Uddin Ahmed Björn Olsen Mohammad Abul Kashem 《Veterinary microbiology》2014
Antibiotic resistance and ESBL constitute a risk to human and animal health. Birds residing close to humans could mirror the spectrum of human associated antibiotic resistance. Household pigeons were screened in Bangladesh to shed light on human associated, as well as, environmental antibiotic resistance. Escherichia coli from pigeons (n = 150) were tested against 11 antibiotics. 89% E. coli isolates were resistant to one or more critically important human antibiotics like ampicillin, cefadroxil, mecillinam, ciprofloxacin, gentamicin and tigecycline. No carbapenamase-producers were detected and the lower ESBL prevalence (5%) in pigeons. ESBL-producing E. coli isolates had blaCTX-M-15 genes. Pigeons shared some bacterial clones and had bird associated sequence types like E. coli ST1408. Fecal carriage of bacteria resistance of critically important human antibiotics, together with examples of shared genotypes among pigeons, indicate the human-birds and bird to bird transmissions are important in the epidemiology of antibiotic resistance. 相似文献
5.
Asraf Mohamed A-S Goda M E Wafa E R El-Haroun & M A Kabir Chowdhury 《Aquaculture Research》2007,38(8):827-837
This study was designed to determine the effect of complete substitution of fish meal (FM) by three plant protein sources including extruded soybean meal (SBM), extruded full‐fat soybean (FFSB) and corn gluten meal (CGM) on growth and feed utilization of Nile tilapia Oreochromis niloticus and tilapia galilae Sarothrodon galilaeus. Four isonitrogenous of crude protein (ca. 28.0%) and isocaloric (ca. 19 MJ kg−1) experimental diets were formulated. The control diet (diet 1) was prepared with FM as the main protein sources. Diets 2–4, each FM control diet, were completely substituted with SBM (diet 2), FFSB (diet 3) and CGM (diet 4). l ‐lysine and dl ‐methionine were added to plant protein diets to cover the nutritional requirements of tilapia. Each treatment was allocated to three net pens and fed for 17 weeks. Nile tilapia fed the control diet showed significantly higher (P≤0.05) values for final body weight (FBW), feed intake (FI), weight gain (WG) and specific growth rate (SGR), whereas fish fed the diet with CGM achieved the lowest values. Tilapia galilae fed SBM diet recorded the highest (P≤0.05) values for growth performance. Better feed conversion ratio (FCR) for both Oreochromis niloticus and Sarothrodon galilaeus was observed when fish were fed SBM diet, whereas the worse FCR was recorded for FFSB diet. Feed utilization parameters including protein productive value (PPV), fat retention (FR) and energy retention (ER) showed significant differences (P≤0.05) for both the species fed different dietary protein sources. The present results suggest that, for Nile tilapia, both SBM and FFSB supplemented with dl ‐methionine and l ‐lysine can completely replace dietary FM. Meanwhile, S. galilaeus fed SBM diet exhibited comparable growth and feed utilization with those fish fed a fish‐meal‐based diet. 相似文献
6.
Effect of salinity on carrying capacity of a recirculation system for Nile tilapia, Oreochromis niloticus L.; production was assessed. Survival, growth and feed conversion ratio of adult Nile tilapia fed 30% crude protein diet for 88 days were measured at three different salinity levels (8, 15 and 25 g L?1) and two stocking densities (20 and 40 m?3) in three independent recirculating systems. Highest survival (98%) and a linear growth in net biomass (P<0.01) was observed in both densities at 8 g L?1 and in 20 m?3 treatment at 15 g L?1. Highest net biomass growth was observed in the 40 m?3 stocking density treatment at 8 g L?1 salinity level (P<0.05). Overall biomass growth was significantly affected by salinity indicating a decrease in Nile tilapia carrying capacity with increased salinity. About 11 000 kg ha?1 crop?1 of Nile tilapia can be obtained in recirculating systems at 8 g L?1 salinity, significantly higher than the net production at 15 g L?1 (5200 kg ha?1 crop?1) and 22 g L?1 (4425 kg ha?1 crop?1). 相似文献
7.
I. Tetens S.K. Biswas L.V. Glitsø K.A. Kabir S.H. Thilsted N.H. Choudhury 《Journal of Cereal Science》1997,26(3):355-361
The hypothesis was tested that certain physico-chemical characteristics might be used as indicators of total starch availability and rate of starch availability of milled rice. Milled unparboiled (uPB) and parboiled (PB) rice samples (n=93) were characterized using standardized methods of physical tests and chemical analyses and anin vitromethod was used for measuring the rate of starch digestion on a subsample of rice (n=26). The rice varieties were dominated by medium long, bold rice grain with high amylose rice and intermediate gelatinization temperature (GT), but a wide range in all characteristics was measured. Small amounts of resistant starch (RS) were measured in the cooked rice, indicating virtually complete starch availability. The RS of PB rice (0·4 g/100 g rice as eaten) was significantly (P<0·004) higher than the RS of uPB rice (0·1 g/100 g) however. The rate of starch digestion was significantly affected by both variety and parboiling. The starch digestion index (SDI) values of the PB samples (mean value 73·7) were significantly (P<0·001) lower than those of the uPB samples (mean value 79·0). The apparent amylose content (AC) was the strongest determinant for SDI in both uPB and PB rice. The widths and shapes of the raw grains and the elongation after cooking were correlated significantly with SDI values for the uPB rice, while the relatively mild parboiling procedure followed in this study eliminated this correlation. The minimum cooking times were correlated significantly with the SDI values in the uPB samples. 相似文献
8.
9.
Clinical exercise testing in the normal Thoroughbred racehorse 总被引:1,自引:0,他引:1
To evaluate normal cardiorespiratory and metabolic responses of Thoroughbred horses to a standardised treadmill exercise test, we examined 28 horses ranging in age from 1 to 4 years. The group consisted of eight yearlings, eight 2-year-olds and twelve 3 and 4-year-olds. All horses except the yearlings were in training, and either racing or ready to race, at the time of examination. None of the horses had histories of performance problems. On the first day the horses received a full physical examination, resting electrocardiogram, upper respiratory tract endoscopy and either one or two acclimatisation runs on the treadmill. The following day they were given an exercise test on a treadmill inclined at 6 degrees (+10% slope). The test consisted of 3 min at 4 m/sec, 90 sec at 6 m/sec and 60 sec intervals at 8, 10, 11, 12 and 13 m/sec. During the last 15 sec of each step, blood samples were collected for plasma lactate determination, expired respiratory gases were obtained using an open flow mask system for measurement of oxygen uptake, and heart rate was measured using telemetry electrocardiogram. From these measurements, various derived values were calculated, which have been used by others as indices of exercise capacity. These values included: V200 (speed at HR of 200 bpm), VHRmax (speed at which horses reached maximum HR), VO2-200 (oxygen uptake at a HR of 200 bpm), VO2max (maximum oxygen uptake), VLA4 (speed at which horses reached a plasma lactate of 4 mmol/l) and HRLA4 (HR at which horses reached a plasma lactate of 4 mmol/l). The yearlings had significantly lower values than the older age groups for most of the derived values.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
10.