全文获取类型
收费全文 | 181篇 |
免费 | 11篇 |
国内免费 | 1篇 |
专业分类
林业 | 26篇 |
农学 | 11篇 |
56篇 | |
综合类 | 8篇 |
农作物 | 11篇 |
水产渔业 | 18篇 |
畜牧兽医 | 42篇 |
园艺 | 4篇 |
植物保护 | 17篇 |
出版年
2023年 | 1篇 |
2022年 | 7篇 |
2021年 | 2篇 |
2020年 | 5篇 |
2019年 | 14篇 |
2018年 | 13篇 |
2017年 | 9篇 |
2016年 | 9篇 |
2015年 | 6篇 |
2014年 | 11篇 |
2013年 | 28篇 |
2012年 | 5篇 |
2011年 | 7篇 |
2010年 | 9篇 |
2009年 | 5篇 |
2008年 | 5篇 |
2007年 | 6篇 |
2006年 | 4篇 |
2005年 | 3篇 |
2004年 | 6篇 |
2003年 | 7篇 |
2001年 | 4篇 |
2000年 | 8篇 |
1999年 | 3篇 |
1998年 | 2篇 |
1997年 | 1篇 |
1996年 | 1篇 |
1994年 | 1篇 |
1992年 | 1篇 |
1989年 | 1篇 |
1987年 | 1篇 |
1986年 | 2篇 |
1984年 | 1篇 |
1983年 | 1篇 |
1980年 | 1篇 |
1979年 | 1篇 |
1978年 | 1篇 |
1960年 | 1篇 |
排序方式: 共有193条查询结果,搜索用时 156 毫秒
171.
The availability of the plastid genome sequences is one of the bases for comparative,functional,and structural genomic studies of plastid-containing living organisms,in addition to the application of plastid genetic engineering technology.The past efforts to sequence plastid genomes involve complicated preparation protocols.One procedure starts with the isolation of plastids,which was tiresome and time wasting that followed by a second step to extract plastid DNA from the isolated plastids,then finally the build up of plasmid or bacterial artificial chromosome (BAC) library. 相似文献
172.
H. Alkher A. El Hadrami K. Y. Rashid L. R. Adam F. Daayf 《European journal of plant pathology / European Foundation for Plant Pathology》2009,124(3):505-519
This study examined cross-pathogenicity of the soilborne pathogen Verticillium dahliae between potato and sunflower. Four week-old potato and sunflower seedlings were inoculated with ten isolates from each of
the two host species. Potato cultivars (Kennebec, susceptible, and Ranger Russet, moderately resistant) and sunflower hybrids
(IS8048, susceptible, and 6946, moderately resistant) were assessed for disease severity and percent infection at 2 weeks,
3 weeks, 4 weeks, 5 weeks, and 6 weeks after inoculation (w.a.i), and for vascular discolouration at 6 w.a.i., using visual
scales developed for each host species. The experiments were conducted in 2006 and repeated in 2007. Based on percent infection
and disease severity, most V. dahliae isolates were highly aggressive on both host species. The tested isolates caused higher disease levels in the susceptible
than in the moderately resistant phenotypes. They also caused more vascular discolouration in their original than in the alternative
host. However, the isolates originating from sunflower caused less infection and disease severity on both hosts, compared
to their potato counterparts. Cluster analysis based on all of the criteria used to assess pathogenicity led to three groups
of isolates: (i) most V. dahliae potato isolates, which ranged with the highly aggressive control isolates, (ii) one V. dahliae sunflower isolate, which showed a similar pathogenicity level to the weakly-aggressive V. albo-atrum sub-group II control isolate, with no more symptoms than in the non-inoculated plants, and (iii) most V. dahliae sunflower isolates with mildly- to weakly-aggressive levels. Based on these results, V. dahliae cross-pathogenicity is very effective between potato and sunflower. Therefore, rotations involving these species should be
avoided, especially where sunflower follows potato. 相似文献
173.
Oral administration of Saccharomyces boulardii alters duodenal morphology,enzymatic activity and cytokine production response in broiler chickens 下载免费PDF全文
Yajing Sun Imran Rashid Rajput Muhammad Asif Arain Yanfei Li Dost Muhammad Baloch 《Animal Science Journal》2017,88(8):1204-1211
The present study evaluated the effects of Saccharomyces boulardii on duodenal digestive enzymes, morphology and cytokine induction response in broiler chicken. A total of 200 birds were allotted into two groups (n = 100) and each group divided into five replications (n = 20). The control group was fed basal diet in addition to antibiotic (virginiamycin 20 mg/kg), and treatment group received (1 × 108 colony‐forming units/kg feed) S. boulardii in addition to basal diet lasting for 72 days. The results compared to control group revealed that adenosine triphosphatase, gamma glutamyl transpeptidase, lipase and trypsin activities were higher, while, no significant improvement was observed in amylase activities in the duodenum of the treatment group. Moreover, morphological findings showed that villus height, width and number of goblet cells markedly increased. Additionally, transmission electron microscopy visualized that villus height, width and structural condensation significantly increased in the treatment group. The immunohistological observations showed increased numbers of immunoglobulin A (IgA)‐positive cells in the duodenum of the treatment group. Meanwhile, cytokine production levels of tumor necrosis factor‐α, interleukin (IL)‐10, transforming growth factor‐β and secretory IgA markedly increased, and IL‐6 statistically remained unchanged as compared to the control group. These findings illustrated that initial contact of S. boulardii to the duodenum has significant impact in improving enzymatic activity, intestinal morphology and cytokine response in broiler chicken. 相似文献
174.
Saeed El-Ashram Fathi Abouhajer Maged El-Kemary Guangping Huang Güngör Dinçel Rashid Mehmood Min Hu Xun Suo 《Veterinary research communications》2017,41(4):263-277
The interactions between gastric microbiota, ovine host, and Haemonchus contortus portray the ovine gastric environment as a complex ecosystem, where all factors play a pertinent role in fine-tuning each other and in haemeostasis. We delineated the impact of early and late Haemonchus infection on abomasal and ruminal microbial community, as well as the ovine host. Twelve, parasite-naive lambs were divided into four groups, 7 days post-infection (dpi) and time-matched uninfected-control groups; 50 dpi and time-matched uninfected control groups were used for the experiment. Six sheep were inoculated with 5000 H. contortus infective larvae and followed for 7 or 50 days with their corresponding uninfected-control ones. Ovine abomasal tissues were collected for histological analysis and gastric fluids were collected for PH value measurements, microbial community isolation and Illumina MiSeq platform and bioinformatic analysis. Our results showed that Haemonchus infection increased the abomasal gastric pH (P = 0.05) and resulted in necrotizing and inflammatory changes that were more severe during acute infection. Furthermore, infection increased the abomasal bacterial load and decreased the ruminal microbiome. A 7-day infection of sheep with H. contortus significantly altered approximately 98% and 94% of genera in the abomasal and ruminal bacterial profile, respectively (P = 0.04–0.05). However, the approximate altered genera 50 days after infection in the ovine abomasal and ruminal microbiome were about 62% and 69%, correspondingly (P = 0.04–0.05) with increase in some bacteria and decrease in others. Overall, these results indicate that Haemonchus infection plays a crucial role in shaping stomach microbial community composition, and diversity. 相似文献
175.
Ahmad Khakwani Muhammad Imran Iftikhar Ahmad Rashid Waqas Sabir Hussain Sajid Mahmood Nadeem 《Communications in Soil Science and Plant Analysis》2017,48(1):73-82
This study was conducted to assess the efficacy of bio-organic phosphate (BOP) and diammonium phosphate (DAP) fertilizers for improving the growth, yield, plant phosphorus (P) content and profitability of wheat cultivation under systems of wheat intensification (direct seeding and nursery transplantation) and conventional sowing (broadcasting). BOP was formulated by enriching the compost with rock phosphate and inoculated with plant growth-promoting rhizobacterial (PGPR) strain, Bacillus thuringiensis strain K5. Results revealed the supremacy of BOP over DAP, and the direct seeding method over the other sowing methods in almost all parameters studied. The application of BOP significantly (p ≤ 0.05) increased the plant height, root length, number of tillers per plant, wheat biomass, number of grains per spike, 1000-grain weight, grain yield, straw and grain P contents in direct seeded wheat in comparison to DAP fertilization. Furthermore, application of BOP and direct seeding of wheat generated more profit per hectare compared with the other treatments. 相似文献
176.
Rokeya Begum Mohammad S. Rahman Sarwaruddin Chowdhury M. Mukhlesur Rahman Simon Gibbons Mohammad A. Rashid 《Fitoterapia》2010
A new coumarin, 7-[(2′E,6′E)-7′-carboxy-5′(ζ)-hydroxy-3′-methylocta-2′,6′-dienyloxy]-coumarin, was isolated from the leaf of Clausena suffruticosa. Its structure was established by means of spectroscopic data analyses, including mass spectrometry and both 1D and 2D NMR spectroscopy. 相似文献
177.
Waseem Shahzad Rashid Munir Mohammad S. Khan Mansur D. Ahmad Mohammad Ijaz Ashfaq Ahmad Mohammad Iqbal 《Tropical animal health and production》2010,42(8):1597-1599
The prevalence of Trypanosoma evansi was investigated in 1,250 Nili-Ravi buffaloes of mixed age and sex by polymerase chain reaction (PCR) for the first time in Pakistan. DNA of the trypanosomes was isolated with TRIREAGENT®. The assay was employed using primers ESAG 6/7, specific for a 237-bp fragment from T. evansi genomic DNA. The samples were screened for the presence of T. evansi also by stained thin smear. Forty-four (3.5%) samples were positive by microscopy, while 97 (7.7%) samples were identified by PCR, indicating the high sensitivity of PCR for surveying the disease in epidemiological studies. 相似文献
178.
Land degradation due to soil erosion is the major problem facing Ethiopia today. In the Lake Alemaya catchment soil erosion is caused by the intense rainfall, steep topography, and poor vegetation cover coupled with cultivation of steep lands, and inadequate conservation practices. Sediment from the catchment has affected the storage capacity of Lake Alemaya. This study has integrated the Agricultural Non‐point Source Pollution Model (AGNPS) and the technique of the Gographic Information System (GIS) to quantify soil erosion in the Lake Alemaya catchment. After application of the AGNPS, it appears that 66 per cent of the catchment has a soil erosion rate of 10 to more than 80 t ha−1 y−1. The annual soil loss is estimated at 31 t ha−1, which is more than the permissible value of 1–16 t ha−1 for different agro‐ecological zones of Ethiopia. The sediment yield of the catchment is about 10 148 ton with a delivery ratio of 6·82 per cent. Therefore, an effective management plan is needed for the conservation and rehabilitation of the catchment and to maintain the storage capacity of Lake Alemaya. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
179.
This report deals with an outbreak of infectious coryza (IC) in a Badosh, Iraq, poultry farm in 1982. It appears to be the first published report of IC in Iraq, although claims of previous occurrence of the disease have been made. 相似文献
180.
Gyo Moon CHU Cheol Kyu JUNG Hoi Yun KIM Ji Hee HA Jong Hyun KIM Min Seob JUNG Shin Ja LEE Yuno SONG Rashid Ismael Hag IBRAHIM Jae Hyeon CHO Sung Sill LEE Young Min SONG 《Animal Science Journal》2013,84(2):113-120
This study was carried out to investigate the effects of bamboo charcoal and bamboo vinegar as alternatives of antibiotics in the diet of fattening pigs and their influence on growth performance, immune responses and fecal microflora populations. Crossed pigs (n = 144, 79 kg body weight) were divided into 12 heads per pen, four diets and three replications. The basal diet (negative control: NC) was supplemented with 0.3% antibiotics (positive control: PC), 0.3% bamboo charcoal (BC) and 0.3% bamboo vinegar (BV). Average daily weight gain and feed efficiency were higher (P < 0.05) in PC, BC and BV. The concentration of lactate dehydrogenase and cortisol were lower (P < 0.05), but the concentration of immunoglobulin G (IgG) and IgA were higher (P < 0.05) in PC, BC and BV. Counts of coliform bacteria and Salmonella spp. were lower (P < 0.05), while the counts of fecal anaerobic total bacteria and lactic acid bacteria were higher (P < 0.05) in PC, BC and BV. A reasonable inclusion of bamboo charcoal or bamboo vinegar as antibiotics in the diet of fattening pigs leads to a better growth performance, immune responses and fecal microflora populations. The results of the present study suggest that bamboo charcoal or bamboo vinegar could be a potential additives in animal production as an alternative to antibiotics. 相似文献