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111.
A 10 year research programme at Lincoln University, investigating the use of Trichoderma species for biological control of soil-borne diseases of vegetable crops, has resulted in the development of two commercial products. Trichodry TM. 6S and Trichoflow TM. 6S based upon Trichoderma hamatum isolate 6SR4, are used to control Sclerotinia lettuce drop disease. The Trichodry 6S product is formulated as a dry flake, which is incorporated into nursery seedling mix and the Trichoflow 6…  相似文献   
112.
Objectives : To review the success rates for liposuction of lipomas in dogs, report early complications and medium‐term outcomes and formulate recommendations on the most appropriate candidates for liposuction. Methods : Retrospective study of 20 dogs with 76 lipomas diagnosed by cytology, in which dry liposuction was attempted. Case records were reviewed for number and size of the lipomas, efficacy of liposuction, frequency and types of complication and likelihood of recurrence. Results : Liposuction was successful in removing 73 of 76 lipomas (96%). Simple, encapsulated lipomas less than 15 cm in diameter were most easily removed, with minimal risk of complication. Giant lipomas contained fibrous trabeculae that hindered liposuction and resulted in poor fat retrieval. Giant lipomas were also associated with a high risk of bruising, haematoma and seroma, especially when inguinal in location. Regrowth was noted at follow‐up between 9 and 36 months in 28% of lipomas. Clinical Significance : Liposuction may be less invasive and more attractive to owners than conventional surgery for lipomas up to 15 cm in diameter. Liposuction is not recommended for infiltrative or giant inguinal lipomas. Regrowth can be expected in a high proportion of lipomas, which should be considered when choosing liposuction over conventional excision.  相似文献   
113.
Nine adult Asiatic black bears (Ursus thibetanus) previously rescued from illegal bile farming in Vietnam were examined via abdominal ultrasound and exploratory laparoscopy for liver and gall bladder pathology. Three bears demonstrated notable gall bladder pathology, and minimally invasive cholecystectomies were performed using an open laparoscopic access approach, standard 10 to 12 mmHg carbon dioxide pneumoperitoneum and a four-port technique. A single bear required insertion of an additional 5 mm port and use of a flexible liver retractor due to the presence of extensive adhesions between the gall bladder and quadrate and left and right medial liver lobes. The cystic duct was dissected free and this and the cystic artery were ligated by means of extracorporeal tied Meltzer knot sutures. The gall bladder was dissected free of the liver by blunt and sharp dissection, aided by 3.8 MHz monopolar radiosurgery. Bears that have had open abdominal cholecystectomies are reported as taking four to six weeks before a return to normal activity postoperatively. In contrast, these bears demonstrated rapid unremarkable healing, and were allowed unrestricted access to outside enclosures to climb trees, swim and interact normally with other bears within seven days of surgery.  相似文献   
114.
The effect of manure and mineral fertilization on the arbuscular mycorrhizal (AM) fungal community structure of sunflower (Helianthus annuus L.) plants was studied. Soils were collected from a field experiment treated for 12 years with equivalent nitrogen (N) doses of inorganic N, dairy manure slurry, or without N fertilization. Fresh roots of tall fescue (Festuca arundinacea Schreb.) grass collected from the field plots without N fertilization and unfumigated field soils were used as native microbial inoculum sources. Sunflower plants were sown in pots containing these soils, and three different means of manipulating the microbial community were set: unfumigated soil with fresh grass roots, fumigated soil with fresh grass roots, or fumigated soil with sterilized grass roots. Assessing the implications with respect to plant productivity and mycorrhizal community structure was investigated. Twelve AM fungal OTUs were identified from root or soil samples as different taxa of Acaulospora, Claroideoglomus, Funneliformis, Rhizophagus, and uncultured Glomus, using PCR-DGGE and sequencing of an 18S rRNA gene fragment. Sunflower plants grown in manure-fertilized soils had a distinct AMF community structure from plants either fertilized with mineral N or unfertilized, with an abundance of Rhizophagus intraradices-like (B2). The results also showed that AM inoculation increased P and N contents in inorganic N-fertilized or unfertilized plants, but not in manure-fertilized plants.  相似文献   
115.
SEED ESTABLISHMENT IN THE WEST OF SCOTLAND   总被引:1,自引:0,他引:1  
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116.
两个试验旨在评价肉牛日粮中紫花苜蓿替代禾本科干草的消化动力学。试验1:要测试的饲草组合分别为:100%大须芒草,25%苜蓿和75%大须芒草,50%苜蓿和50%大须芒草,100%苜蓿。采用非线性回归测定即刻可溶性分数A,潜在的可降解分数B,不降解分数C,干物质和中性洗剂纤维消失率。随着苜蓿添加量的增加,干物质分数A线性升高(P=0.03),干物质和中性洗剂纤维分数B线性降低(P=0.01),干物质和中性洗剂纤维消失率线性升高(P≤0.02)。试验2:采用2×2因子设计,测试苜蓿替代鸭茅干草和采食水平的影响。苜蓿添加水平为不添加或含25%(作为饲喂基础),采食水平为每天限制在体重的1%(以干物质为基础)或自由采食。限饲组肉牛营养素摄入量最低(P≤0.05),自由采食鸭茅干草的肉牛营养素摄入量居中,自由采食鸭茅干草和苜蓿的肉牛营养素摄入量最高。采食水平和饲草来源对除蛋白质外的所有营养素的总消化道表观消化率没有影响(P≥0.23)。与单独饲喂鸭茅饲草的肉牛相比,采食鸭茅干草和苜蓿的肉牛蛋白质总消化道表观消化率显著提高33%(P=0.01)。干物质和中性洗剂纤维消失的延迟时间不受苜蓿或采食水平影响(P≥0.20)。限制日粮组和自由采食组,与单独采食鸭茅饲草的肉牛相比,采食鸭茅饲草和苜蓿的肉牛对鸭茅饲草干物质和中性洗剂纤维的消失率更快(P≤0.01)。与限饲组肉牛相比,自由采食组肉牛对鸭茅饲草大、小颗粒的平均贮留时间有缩短的趋势(P≤0.06)。在自由采食和添加苜蓿的条件下,小颗粒鸭茅饲草通过率趋向于更快(P=0.09)。自由采食与鸭茅饲草平均贮留时间缩短和小颗粒鸭茅饲草通过率加快相关;然而添加苜蓿能提高小颗粒鸭茅饲草通过率,干物质和中性洗剂纤维消失率。  相似文献   
117.
Douglas-fir (Pseudotusga menziesii (Mirb.) Franco), a native to the Pacific Coast Range in North America, is recognized as a tree that is long-lived and can grow rapidly to standing volumes that approach the highest recorded for temperate conifers. Managed plantations in western Oregon register maximum periodic annual increments (PAI) at ages between 20 and 40 years of ∼30 m3 ha−1 year−1. The same seed source, when planted in New Zealand and elsewhere in the Southern Hemisphere, may attain a PAI of ∼50 m3 ha−1 year−1. Is this higher productivity mainly related to climate or to isolation from native pests? To evaluate the role of climate, we obtained meteorological data from plantation sites in New Zealand and Oregon, from which we established relationships between mean monthly temperature extremes and solar irradiance, air humidity deficits, and frost frequency. Using these empirical relationships, long-term weather records were converted to the meteorological variables required to drive a process-based forest growth model, 3-PG, for sites approaching the most productive in New Zealand and in Oregon. Annual precipitation is similar in both areas, but sites in Oregon receive only 10% during the growing season, resulting in humidity deficits 30% larger than those recorded in New Zealand. According to sensitivity analyses and direct measurements, the more productive Douglas-fir forests in Oregon avoid the limiting effects of summer drought by obtaining water from the subsoil and fractured bedrock. If such forests were under a reduced evaporative demand similar to that in New Zealand, we show that they would exhibit comparable productivity.  相似文献   
118.
DM yield and N uptake data are presented from primary growth and two successive regrowths of perennial ryegrass treated with combinations of three N treatments for the primary growth viz. 0, 50 and 100 kg N/ha (PN) and four N treatments applied for the second growths, viz. 0, 33, 66 and 100 kg N/ha (SN). Primary growth gave a response of 24·2 kg DM/kg applied N to PN50 with only a further l±0 kg DM/kg applied N from the second PN increment. A significant interaction between PN and SN treatments was shown in second growth. The residual DM response to PN was highest at SN0 and reduced as the level of SN was raised. Substantially greater residual responses to PN treatments were shown in the third growth. Third growth DM responses to SN treatments were high. High apparent recovery of fertilizer N reached 111% of primary N where SN66 followed PN50. High available soil N is partly responsible for both high apparent recovery of N and high DM response. The latter appears to be associated with inclusion of growths given no fertilizer N so that the full residual effects of fertilizer N and ‘priming’ of available soil N can be realised.  相似文献   
119.
The effects of 59, 118 or 177 kg N/ha were measured on 7 occasions from 8 to 57 days after application to a perennial ryegrass sward in terms of changes in composition. The first increase Dt of N significantly raised percentages of CP, non-protein N, K, P, Ca, Na and Mg and significantly depressed percentages of DM, OM and OM digestihility. The second increment of N resulted in a further rise in the percentages of CP, true protein, non-protein N, K, P, Ca, Na and Mg; the percentages of DM and OM were further depressed but OM digestihility was not significantly depressed. Percentages of P and Na showed increased responses for the more mature herbage; while percentage non-protein N showed a more marked response in younger herbage. As herbage matured percentages of OM and Na rose, the latter only from days 16 to 45. All other attributes showed falling percentages to levels which could be inadequate for a 500 kg dairy cow yielding 15 kg milk. CP percentage reached this critical level (1.4% N) at days 37, 45 or 56 given 59, 118 or 177 kg N/ha; P percentage became critically low (< 0.36%) at days 27, 35 or 38, respectively; Mg percentage fell to the critical level (0.12%) at days 23, 35 and 46. Na percentage showed the reverse trend, being deficient (< 0.13%) in the earliest samples and becoming satisfactory from days 23 or 27 at 118 and 177 kg N/ha but it remained inadequate at 59 kg N/ba.  相似文献   
120.
Fifteen out of 36 possible combinations of 3 cutting dates for hay, 3 rates of N application and 4 intervals between N application and cutting date were compared to study the effects of pre-harvest application of N on the N, P, K, Mg and Ca contents of the aftermath and the effectiveness of utilization of these elements. According to the method of calculation given by ARC (1), the control haycrop harvested on 16 June was deficient in N, Ca, P and Mg, and the aftermath which was given no further N after harvest was of low bulk, but adequate in mineral content. Earlier harvesting improved the quality of the hay, and increased the bulk and reduced the mineral content of the aftermaths. Applying 125.6 kg N/ha after harvest resulted in a satisfactory increase in bulk, plus an improved mineral content in the aftermath. Applying N before harvest resulted in increased uptake of N, K, Ca, P and Mg in the hay and in the increased percentage of N, K, and Ca in the DM of the hay. Very early application of pre-harvest N increased the percentage of Mg. The general effect of pre-harvest N on the aftermath was to reduce yield and uptake of N, K, Ca, P and Mg. Doubling the pre-harvest N raised the mineral uptake. Very early pre-harvest application resulted in low mineral uptake in the aftermath. The percentage of N, K and P in the aftermath was reduced by pre-harvest N applied at both levels and on both dates. Deferring the application of fertilizer N until 4 days after harvesting the hay crop produced the highest mineral contents in the aftermath, without reducing its bulk. Mineral uptake in the regrowths was linearly related to N uptake at 1.43 kg K, 0.34 kg Ca, 0.157 kg P, 0.006 kg Mg/kg N uptake.  相似文献   
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