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991.
S. H. De Boer 《American Journal of Potato Research》1991,68(2):107-113
The bacterial ring rot disease of potato (Corynebacterium sepedonicum) can be detected in seed potato lots by serological tests with greater accuracy than by visual field inspections. Indexing tests can make use of highly specific immunofiuorescence probes, enzyme-linked immunosorbent assays, and perhaps other procedures. Sensitivity and specificity of these procedures need to be determined in order to estimate the confidence with which ring rot can be detected in a seed lot. In addition to the laboratory tests, the sampling strategy determines the efficacy and sensitivity of the indexing procedure. Samples might consist of stems, leaf petioles, or tubers in single or composite units. Disease incidence and number of plants sampled also determine the confidence level with which ring rot can be detected in a potato seed lot. Although research has been conducted on many aspects of ring rot testing procedures, further work needs to be done. Nevertheless, it is anticipated that indexing potato seed lots for the presence of ring rot will be a significant factor in control and eradication of the disease. 相似文献
992.
Summary From 1985 to 1987 field experiments were caried out to test the influence of different pre-planting storage treatments on
yield and size distribution of potato crops. The storage treatments included 4, 8 and 12°C in the light and in the dark, for
different periods before planting. Subjecting the seed tubers to light at low temperatures induced crops to produce a larger
proportion of smaller sized tubers while storing seed tubers at higher temperatures in the dark led to an increase of tubers
>55 mm. These observations were confirmed in five field experiments with two cultivars at two sites and in three growing seasons. 相似文献
993.
994.
Ac novachip: a new potato cultivar with excellent chip quality after long storage and reconditioning
H. De Jong G. C. C. Tai A. M. Murphy T. R. Tarn J. H. E. Thorpe W. J. Arsenault R. H. Bagnall H. W. Platt D. A. Young 《American Journal of Potato Research》1995,72(7):417-425
AC Novachip is a smooth, white-skinned potato cultivar with oval to oblong tubers and a maturity similar to Kennebec. It has excellent chip quality, especially after long storage and reconditioning. The boil and bake quality is similar to Kennebec; the specific gravity is higher than Kennebec but lower than Atlantic. AC Novachip has moderate resistance to common scab and PVY. 相似文献
995.
我国南方大豆地方品种农艺和品质性状的遗传参数分析 总被引:5,自引:0,他引:5
由南方13省区的3769份夏大豆地方品种按省分层随机抽样而得的143份材料组成地方群体;由20份南方夏大豆推广品种及品系组成改良群体,在南京两年三重复试验表明,南方地方群体主要特点是晚熟(132.56天),秆较矮(58.05cm),中粒(14.34g/100粒),底荚高(18.47cm),分枝中等(3.86),产量低(1199.25kg/ha),蛋白质含量高(43.73%)、脂肪含量中等(20.19%)。该群体农艺和品质性状具有丰富的遗传变异,并由5%相对遗传进展特点将45个性状分为,GSI:极大(>40%);GSⅡ:大(40%—10%);GSⅢ:中等(10%—5%);GSⅣ:一定(<5%)等四类,其中GSⅠ、GSⅡ类多属产量、生育期、粒茎比、株高、百粒重等农艺性状,GSⅢ、GSⅣ类多属蛋白质含量及其氨基酸组分、脂肪含量等品质性状。 相似文献
996.
997.
998.
施肥对小麦根系活性、延缓旗叶衰老及产量的效应 总被引:25,自引:6,他引:25
1996-1998年,在大田生产条件下,就施肥水平对小麦群体根系活性,延缓旗叶衰老及籽粒产量的影响进行了比较研究。结果表明,土壤肥力和施肥水平对小麦的群体根系活性有显著的调控作用,土壤肥力高则根系活性强。施肥可明显促进小麦群体根系活性的提高,延缓旗叶衰老(增加叶绿素含量,提高光合速率,增强SOD和POD活性,降低MDA含量), 显著提高小麦籽粒产量,其中有机无机肥配施效果更佳。 相似文献
999.
Doolaege EH Raes K De Vos F Verhé R De Smet S 《Plant foods for human nutrition (Dordrecht, Netherlands)》2011,66(2):196-202
The absorption, distribution and elimination of carnosic acid, the main antioxidant found in rosemary was studied, in vivo, in rats. Therefore, carnosic acid was administrated in a single dose, intravenously (20.5 ± 4.2 mg/kg) and orally (64.3 ± 5.8 mg/kg),
to four and nine rats, respectively. Blood samples were collected at different time points, and plasma concentrations of carnosic
acid were determined using LC-MS. Furthermore, total collection of urine and feces was done during 4 h and 24 h for the intravenous
and oral administrations, respectively. After euthanizing the rats, intestinal content, liver and muscle tissue were sampled
to determine carnosic acid concentrations. The bioavailability of carnosic acid, after 360 min, was 40.1%. Traces of carnosic
acid were found in the rats intestinal content, liver and muscle tissue of abdomen and legs. The recovery of carnosic acid
in the feces, 24 h after oral administration, was 15.6 ± 8.2%. Carnosic acid is absorbed into the bloodstream after oral administration
in rats and is therefore bioavailable. It was found that carnosic acid in vivo is present in its free form and that its main elimination route is the fecal route. 相似文献
1000.
Summary Based on visual inspection, discrimination between common scab (Streptomyces spp.) and powdery scab (Spongospora subterranea) can be difficult. Inspections are performed on unwashed samples, incidentally supported by microscopic examination.
During 1994–1996 surveys were performed in The Netherlands on tubers with symptoms resembling common scab. Under microscopic
assessment nearly all samples showed the presence of structures resembling cystosori (sporeballs) ofS. subterranea. At that time confirmation using alternative techniques was not possible.
In 2003 research was undertaken to clarify the situation with respect to scab on potato tubers in The Netherlands. One hundred
and eighteen scab samples were extensively tested forS. subterranea. All samples were digitally photographed, microscopically examinated and tested with real-time PCR and DAS-ELISA. Use of
these modern methods resulted in a clear picture of symptoms that can be attributed toS. subterranea. A lot of scab samples with structures resembling cystosori could not be confirmed as contaminated withS. subterranea. 相似文献