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961.
Debra C. Stowe Mohammed S. Lamhamedi Sylvie Carles Bertrand Fecteau Hank A. Margolis Mario Renaud Pierre Y. Bernier 《New Forests》2010,40(2):185-204
Increasing irrigation efficiency and reducing groundwater contamination from agricultural and nursery runoff are important
components in environmentally compatible plant production practices. The objectives of this study were to quantify mineral
leaching from containerized (2+0) white spruce seedlings grown under three different irrigation regimes (30, 40 and 55% V/V)
and to determine the effect of irrigation regime on growth, nutritional status, and gas exchange. To negate the effect of
environmental variables, a completely randomized block experiment was installed in a normal production run of air-slit containerized
white spruce seedlings grown under an unheated polyethylene tunnel. Whereas substrate water content was monitored daily, biweekly
measurements of tissue and substrate fertility and seedling morphophysiological variables were made over the course of the
growing season. Leaching of mineral nutrients was continuously monitored throughout the experimental period. Reducing volumetric
substrate water content from 55 to 30% did not have a significant effect on seedling growth, carbon allocation, tissue nitrogen
content, or end-of-season morphology. This irrigation strategy also resulted in a 20% reduction in water usage and, more importantly,
reduced the total leachate volume by 65% and the quantity of N leached by 52%. Maintaining rhizosphere water content of (2+0)
white spruce seedlings at 40% V/V compromises neither plant growth nor physiological processes. This strategy limits leaching
of water and mineral nutrients, and reduces the risk of groundwater contamination, thus enabling growers to meet both quality
and environmental standards for seedlings grown in northern forest nurseries. 相似文献
962.
Tarit Kumar BAUL Mohammad MEZBAHUDDIN Mohammad Mosharraf HOSSAIN Mohammed MOHIUDDIN 《中国林学(英文版)》2010,12(4):228-235
The present study investigated the rooting ability and growth performance of juvenile single-node leafy stem cuttings of 相似文献
963.
964.
Early diagnosis of MAP infection is a pressing need to enable efficient intervention with the spread of MAP infection in herds. Hence, study of lymphocyte subsets and their expressed adhesion molecules could contribute in defining a distinct diagnostic marker (or markers) at the subclinical period of the infection that could in turn facilitate the development of effective diagnostic approach. In accordance with this objective, milk and blood samples were collected from two groups of cattle naturally infected with MAP and their corresponding negative controls. Group (C) comprised 3-4 year-old ELISA negative/PCR positive-cattle that were considered as subclinical seronegative low shedder group (early stage). Group (A) included 6-8 year-old ELISA positive-cattle, which were considered as a clinical seropositive group (late stage). Flow cytometry of B cells, CD8+, CD4+ and γδ cells and the adhesion molecules CD44+, CD62L, LFA-1 and LPAM-1 indicated increase in CD4+ and B cells levels, with higher levels in blood than milk of group A, and significant expression of CD44+ in blood and milk and LPAM-1 in blood only. The CD8+ cells count in milk was higher than blood in the late stage. The peculiar feature of the early stage (group C) was the high level of γδ cells in the blood and milk, with tendency to express high level of CD62L. Compelling evidence could support the assumption that the dominant γδ cells at early stage of MAP infection could be of CD8CD2−WC+1+ phenotype. γδ cells appear as promising markers in defining early changes of MAP infection due to their important role in priming innate and cell mediated immunity. Possible utilization of these peculiar changes in the γδ cells level in the early diagnosis of MAP infection should be the subject of further research. 相似文献
965.
Youssef Mohamed A. El-Khodery Sabry Ahmed El-deeb Wael M. El-Amaiem Waleed E. E. Abou 《Tropical animal health and production》2010,42(8):1771-1777
As little is known about the oxidant/antioxidant status in buffalo with ketosis, the present study was delineated to assess
the oxidative stress level associated with clinical ketosis in water buffalo. A total of 91 parturient buffalo at smallholder
farms were studied (61 suspected to be ketotic and 30 healthy). Clinical and biochemical investigations were carried out for
each buffalo. Based on clinical findings and the level of beta-hydroxybutyrate (BHB), buffalo were allocated into ketotic
(42), sublinical cases (19). Clinically, there was an association between clinical ketosis and anorexia (p < 0.001), constipation (p < 0.001), decreased milk yield (p < 0.001), ruminal stasis (p < 0.001), and loss of body condition (p < 0.01). Biochemically, in clinical ketosis compared with subclinical and control cases, there was a significant increase
(p < 0.05) of BHB, malondialdehyde (MDA), nitric oxide (NO), aspartate aminotransferase (AST), L-alanine aminotransferase (ALT).
However, there was a significant decrease of glucose, phosphorus, magnesium,total cholesterol and HDL-cholesterol. There was
a positive correlation between BHB and MDA (r = 0.433), BHB and NO (r = 0.37), MDA and NO (r = 0.515), and Glucose and phosphorus(r = 0.521). However, there was a negative correlation between BHB and glucose (r = −0.341) and HDL and NO (r = −0.379). The result of the present study indicates that hyperketonemia in buffalo is associated with an increase of oxidative
stress levels. Further studies need to be done on the efficacy of antioxidants as an ancillary treatment to relief the oxidative
stress caused by ketosis. 相似文献
966.
Xiaoping Wu Kun Qian Aijian Qin Haiyu Shen Pingping Wang Wenjie Jin Yassir Mohammed Eltahir 《Veterinary research communications》2010,34(7):619-632
Background
Five isolates (JS09GY2, JS09GY3, JS09GY4, JS09GY5, and JS09GY6) of avian leukosis virus subgroup J (ALV-J) were isolated from six infected commercial layer flocks displaying both hemangioma and myeloid leukosis (ML), which shared the same parental line, in China in 2009. 相似文献967.
Benjamin Obukowho Emikpe Mohammed Y. Sabri Stephen O. Akpavie Mohammed Zamri-Saad 《Veterinary research communications》2010,34(7):569-578
Nigerian strain of Peste des Petit Ruminant (PPR) virus and Mannheimia haemolytica (MH) biotype A serotype 2, was used successfully to reproduce a concurrent disease in West African Dwarf goats. The development
of the various pathological features were studied at regular intervals following infection. The acute inflammatory reaction
which had developed by day 3 after initial infection was characterised by flooding of the alveoli by neutrophils, oedema,
hemorrhage and syncytial cells together with a moderate bronchial and bronchiolar epithelial necrosis. This progressed to
a milder acute broncho interstitial pneumonia with giant cells. At this stage, the mucosal immunity were well developed especially
the aggregate form of NALT and more of nodular forms of BALT. The organisms were demonstrated with strong immunostaining in
the necrotic center, necrotic alveolar wall, fibrin, serous exudate, and degenerated leukocyte in the alveoli and respiratory
airways. The bacterial antigens were observed as a strong immunostaining in the blood vessels of the nasal septum, sinusoid
in the liver and interstium of the kidney, cytoplasm of alveolar macrophages, pneumocytes, bronchial and bronchiolar epithelium,
in the monocytes in the blood vessels. These findings confirmed the enhancement of MH tropism especially in the respiratory
tract, liver and kidney. It also showed that West african dwarf goats are highly susceptible to the intratracheal combined
infection of PPR virus and MH. The fact that the infection induces strong mucosal responses, this phenomenon can be explored
in Africa with the use of combined PPR virus and MH intranasal vaccines to curtail the menace of pneumonia associated with
the combined infection on field. 相似文献
968.
Fusarium basal rot caused by Fusarium oxysporum f.sp. cepae is an economic disease of shallot. Field experiments were conducted at Debre Zeit during 2006 and 2007 cropping seasons to determine effective fungicides and their method of application for the management of fusarium basal rot of shallot. The field was naturally infested with F. oxysporum f. sp. cepae and treatments were arranged in randomized complete block design in four replications. Five fungicides, Mirage 50 WP, Folicur 25 EC, Seed plus 30 WS, Penncozeb 80 WP and Ridomil Gold 68 WG were evaluated as seed bulb dressing and bulb dip treatments against basal rot in the field and storage. Bulb dressing with Mirage, and dip treatment in Seed plus reduced the disease incidence by 40% and 43%, respectively over control. These fungicides also resulted in a significant reduction in severity, basal rot affected cull bulbs on shallot. Bulb rot during three months of storage on concrete ground floor and on wire mesh shelves was also reduced by seed bulb treatment over control. The highest increase in yield was obtained from bulb dressing with Mirage (42%) and Seed plus (45%) and from bulb dip treatment in Seed plus (44%) over control. Fusarium basal rot caused 45% loss in yield and 12-30% of bulb loss in the storage. The study showed that basal rot of shallot can be managed effectively by seed bulb dressing or dip treatment in Mirage or Seed plus. 相似文献
969.
970.
Annabelle J Bladon Katherine M Short Essam Yassin Mohammed E J Milner‐Gulland 《Fish and Fisheries》2016,17(3):839-859
Payments for Ecosystem Services (PES) is a powerful economic tool that gives positive conditional incentives for the provision of additional ecosystem services over the status quo, which has been used widely in terrestrial conservation. Interest in the concept of marine PES has recently emerged, but the fluid, transboundary and often common pool nature of marine ecosystems presents challenges for PES design and implementation. Here, we consider the potential role of PES in addressing current gaps in fisheries management. Used in combination with conventional regulatory approaches, PES may increase private sector engagement and generate more sustainable financing for fisheries management whilst spreading accountability throughout the supply chain. The approach is most likely to be feasible and effective in commercially valuable fisheries with: (i) demand for one or more ecosystem service and a threat to supply; (ii) suitable baseline data available and potential management actions underpinned by robust science; (iii) clarity and security of property rights; (iv) capacity for hybrid multi‐level governance; (v) capacity for rigorous monitoring, control and surveillance; and (vi) potential for financial sustainability of the scheme. An examination of four contrasting fisheries – Namibian hake, Mozambican shallow‐water shrimp, Western and Central Pacific skipjack tuna and Bangladesh hilsa – demonstrates that a developing world fishery will rarely fulfil each of these preconditions a priori, but that the potential for successful application of PES still exists. In practice, PES design will depend on the institutional context and require creative and innovative approaches to the maintenance of conditionality and additionality. 相似文献