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471.
Summary The selective-diagnostic crystal violet pectate (CVP) medium for the detection and isolation of soft rot erwinias was modified
and improved to allow the use of a new source of sodium polypectate (Slendid type 440), as the previous polypectate (Bulmer)
is no longer available. Two formulations were developed: CVP-S1 medium was less transparent but otherwise similar to the Bulmer
polypectate-based CVP medium (CVP-B) except that NaOH was added and CaCl2 concentration reduced. CVP-S2 medium was prepared by mixing equal volumes of two double strength preparations containing
1) polypectate and NaOH, and 2) all other ingredients, both sterilised separately. Although erwinia cavity formation was slower,
it showed a number of advantages over CVP-B and CVP-S1 media, thereby facilitating colony/cavity detection and enumeration.
These included the absence of precipitate, greater firmness and a reduced risk of liquefaction in the presence of large erwinia
numbers, and a reduction in the number of saprophytic bacteria. 相似文献
472.
A. Bascu?án K.M. Thieman Mankin A.B. Saunders J.M. Bright V. Scharf A. Singh L. OSullivan B. Brisson A.H. Estrada S.P. Tou C. Ruoff 《Journal of Veterinary Cardiology》2017,19(1):35-43
Objectives
To describe signalment, clinical characteristics, diagnostic, treatment, and outcome data in a large case series of cats with patent ductus arteriosus (PDA).Animals
Fifty cats with confirmed PDA.Methods
Retrospective review of medical records from five referral veterinary hospitals for cats with PDA between 2000 and 2015. Cats were included if a PDA was visualized echocardiographically, during surgery, or on post-mortem examination.Results
Median age at presentation was 6 months (range: 36 days–9.7 years; n = 50), and sex distribution was approximately equal (27 male, 23 female). Most cats did not have clinical signs (70.2%; 33/47) at the time of presentation. Murmurs were classified as continuous (55%; 22/40) or systolic (45%; 18/40). Echocardiography confirmed left-to-right shunting in 33 cats (82.5%; 33/40) and right-to-left shunting in 7 (17.5%; 7/40). Concurrent cardiac anomalies were identified in 54.5% (18/33) and pulmonary hypertension in 45.7% (16/35). Closure was pursued in 68% (34/50), and complications associated with the procedure occurred in 14.7% (5/34) of cats, including one intraoperative mortality. Long-term follow up was available in 80% (40/50) of cats.Conclusions
Cats with PDA often do not display clinical signs and may not have the characteristic physical examination findings typical of PDA in dogs. An increased prevalence of concurrent cardiac anomalies and pulmonary hypertension were found relative to previous reports. Thoracic radiographs and echocardiogram may provide the most comprehensive information for making a diagnosis and treatment recommendations. PDA closure was associated with a favorable long-term outcome in cats included in this study. 相似文献473.
C. Lin M. Rosicky D. McConchie L. A. Sullivan G. Lancaster 《Land Degradation \u0026amp; Development》2001,12(4):293-303
Scalded lands are common in acid sulphate soil areas on the New South Wales coast, Australia. In this work, chemical characteristics of the scalded acid sulphate soils at nine sites along this coast were investigated. The investigated acid sulphate scalds are characterized by an extremely acidified topsoil layer (0–0.6 m) although they derive from the sediments of varying salinity and the metal sulphides contained in the soils have experienced different degrees of oxidation. Almost all of the investigated scalds occur in the areas that have a lower surface elevation than the surrounding areas. These hollows may act as sinks for acid sulphate materials and salts that are transported from the surrounding areas and the shallower watertables in such locations may enhance upward transport of acid and salt materials from the underlying oxidized sulphidic sediments. In general, the scalded acid sulphate soils have less organic matter and soluble phosphorus, and a greater salinity, soluble acidity, soluble Al, Mn and Zn concentrations, compared to the adjacent non‐scalded acid sulphate soils. These are most likely soil constraints for revegetation of the scalded lands and treatment will need to involve acid neutralization (e.g. application of lime) and addition of P fertilizers to reduce the soluble acidity, immobilize soluble Al, Mn and Zn, and increase P availability. The evidence also shows that the higher soluble Al concentration in the scalded soils, relative to the non‐scalded soils, is related to their lower organic matter content. Hence, rehabilitation of these scalded lands should involve the addition of organic matter to reduce soluble Al concentrations; it may also help reduce Mn and Zn toxicity, and salinity. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献