首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   61篇
  免费   2篇
林业   5篇
农学   1篇
  13篇
综合类   15篇
农作物   1篇
水产渔业   3篇
畜牧兽医   19篇
园艺   6篇
  2022年   1篇
  2021年   1篇
  2018年   3篇
  2015年   1篇
  2014年   1篇
  2013年   8篇
  2012年   1篇
  2011年   4篇
  2010年   3篇
  2009年   1篇
  2008年   7篇
  2007年   2篇
  2006年   4篇
  2005年   1篇
  2004年   2篇
  2003年   4篇
  2002年   1篇
  1989年   1篇
  1988年   1篇
  1987年   2篇
  1986年   2篇
  1985年   1篇
  1984年   2篇
  1983年   1篇
  1980年   1篇
  1974年   1篇
  1971年   1篇
  1970年   2篇
  1967年   2篇
  1966年   1篇
排序方式: 共有63条查询结果,搜索用时 93 毫秒
1.
2.
An understanding of variation in fruit quality in relation to tree age can help understand the issue of poor fruit quality in young orchards; however, limited information is available on the citrus fruit. In this study, the endogenous nutritional status in rind, rag, and leaves; pectin status in rind and rag; and anatomical fruit growth parameter in rind tissues were studied in ‘Kinnow’ mandarins fruit during their development on trees from three age (6-, 18-, and 35-year-old) groups. In older (35-year-old) trees, rind, rag, and leaf nitrogen (N), phosphorus (P), and potassium (K) concentrations were superior. In fruit from all tree age groups, total pectin and protopectin reduced; however water-soluble pectin (WSP) improved. In rind tissues harvested from young (6-year-old) trees, cell density was more while cell size was less. In all tree age groups, cell density in rind tissues correlated negatively with rind WSP.  相似文献   
3.
Journal of Soils and Sediments - Dissipation of pharmaceutical compounds entered into the natural environment is an important process minimizing the adverse effects on the living organisms. The aim...  相似文献   
4.
Intravenous alfaxalone, administered at a dose of 5 mg/kg in the jugular vein, was evaluated in 20 leopard geckos (Eublepharis macularius) to ascertain its ability to provide anesthesia. The induction time, time to loss of mandibular tone, interval of deep anesthesia, and full recovery time were 27.5 ± 30.7 seconds (10 to 56 seconds), 1.3 ± 1.4 minutes (11 seconds to 4 minutes), 12.5 ± 2.2 minutes (11.11 to 15.39 minutes), and 18.8 ± 12.1 minutes (10.4 to 52.31 minutes), respectively. A significant reduction in heart rate (74 ± 12.9 beats/minute) was recorded between 2 and 24 minutes after alfaxalone administration. A significant decrease in respiratory rate (26.8 ± 10.1 breaths/minute) was recorded 2 minutes after alfaxalone administration, and respiratory rate remained lower than the basal rate (31.4 ± 3.1 breaths/minute) for 24 minutes but without statistical significance. The intravenous administration of alfaxalone in leopard geckos achieved a rapid onset of anesthesia and a suitable recovery time. Based on this investigation, an afaxalone dose of 5 mg/kg intravenously proved to be suitable for sedation before tracheal intubation. Moreover, the administration route via the jugular vein, was acceptable in leopard geckos; a species in which other venipuncture sites can be challenging or inaccessible.  相似文献   
5.
Subcutaneous phaeohyphomycosis caused by Moniliella suaveolens in two cats   总被引:1,自引:0,他引:1  
Moniliella suaveolens was isolated in pure culture from histologically typical phaeohyphomycotic granulomas containing dematiaceous fungi in two cats. One cat had several slow-growing black lesions up to 2 cm in diameter in the abdominal subcutis. These lesions recurred after surgical excision was attempted. The second cat had a single black subcutaneous 0.5 X 1.5-cm lesion near one dewclaw. This lesion was successfully removed surgically without recurrence. M. suaveolens has not been isolated previously from lesions in animals including man.  相似文献   
6.
  1. Although the frequency of occurrence of plastic ingestion in the large-sized dolphinfish and tunas taken by the Hawai'i longline fishery is very low (frequency of occurrence < 5% of sampled individuals), the ingestion of plastic in smaller-sized specimens caught with pole-and-line gear by commercial and recreational fishers has not been investigated.
  2. This study examined ingestion of >0.25 mm marine plastic debris (MPD) by four predatory fish species caught by commercial fishers around the Main Hawaiian Islands, and documented ingestion in three species: 85.7% of albacore tuna (n = 7), 40.0% of skipjack tuna (n = 10) and 12.5% of dolphinfish (n = 8).
  3. Yellowfin tuna (n = 10) did not contain any MPD, probably owing to the high proportion of empty stomachs (60%).
  4. For skipjack tuna, the frequency of occurrence of MPD ingestion was significantly higher for the smaller-sized specimens caught with pole-and-line (40%), compared with the larger-sized specimens caught with longlines (0%).
  5. For dolphinfish, the frequency of occurrence of MPD ingestion was similar for the similar-sized specimens caught with pole-and-line and with longlines.
  6. The ingested MPD items were micro–meso plastics, between 1 and 25 mm. While most ingested items were fragments, albacore also ingested line and skipjack also ingested sheets.
  7. The predatory fishes ingested light MPD items that float in sea water, but there were species-specific differences in their polymer composition: albacore contained more polypropylene and polyethylene, and skipjack contained more elastomers, characterized by a high percentage of ester plasticizers.
  8. Altogether, these results suggest that albacore and skipjack tunas ingest plastic of different types and polymers. Yet more research is needed to understand how differences in vertical distribution, foraging ecology and diet influence the MPD sampled by these predatory fish species.
  相似文献   
7.
Among the treatments of exogenous foliar spray application of sulphates of cobalt (Co) and cadmium (Cd) at 0, 250, 500, 1000, and 1500 ppm, and nickel (Ni) at 0, 100, 200, and 400 ppm prior to flower bud differentiation in the first week of October, cobalt sulphate (1000 ppm) or cadmium sulphate (1500 ppm) significantly (P=0.05) reduced floral malformation of mango (Mangifera indica L) cv. Langra by 65 to 71% and increased the fruit yield by 35 to 37%. The physical characteristics of the fruit were not affected significantly at the lower concentrations but higher concentrations of Co and Cd caused reduction. Total and non‐reducing sugars in the fruit were adversely affected by the higher rates of Co and Ni applied, but exhibited no effect on total soluble solids percentage (TSS%) or reducing sugars. The foliar spray application of the sulphates of Co, Ni, and Cd increased their respective concentrations in the leaf tissue without any phytotoxic symptoms. Most of the desirable effects were achieved with the 1000 ppm cobalt sulphate treatment applied in the first week of October prior to flower bud differentiation.  相似文献   
8.
The concentrations of iron (Fe), zinc (Zn), manganese (Mn), copper (Cu), and cobalt (Co) in malformed and healthy panicles of mango (Mangifera indica L.), leaves and shoots bearing them were analyzed at: (i) fully swollen bud, (ii) bud inception, (iii) fully grown panicles prior to full bloom, and (iv) full bloom over three consecutive years. The concentrations of Fe, Zn, Cu, Mn, and Co varied in malformed and healthy organs at various developmental stages. Malformed panicles exhibited lower levels of Fe, Zn, Cu, and higher Mn than healthy ones. The leaves on the shoots bearing malformed panicles showed higher levels of Fe, Mn, Cu, and higher Zn than the leaves on the shoots bearing healthy panicles. The shoots bearing malformed panicles revealed higher levels of Fe, Zn, Mn, and Cu than shoots bearing malformed panicles. The levels of Co in healthy and malformed organs did not differ much. The findings of the present study, therefore, seem to point that floral malformation in mango is not caused by the deficiency of these micronutrients.  相似文献   
9.
The composting of organic waste materials using earthworms yields the value-added product vermicompost (VC). The use of VC as a growing substrate amendment for containerized horticultural crop production is a sustainable nutrient management approach which can benefit crop production by providing plant nutrients and improving crop growth. In order to provide nutrient management guidelines for users of VC amended container substrates, a study was conducted to quantify nutrients supplied to substrates solution and to develop nutrient release kinetic models to predict plant available nutrient based on total initial loading rates. Experimental treatments and results were expressed on a volume basis (4-L container) for easy interpretation and application by growers of crops in containers.  相似文献   
10.
Region-specific expression of two mouse homeo box genes   总被引:15,自引:0,他引:15  
  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号