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81.
《Scandinavian Journal of Forest Research》2012,27(1):30-38
The effect of different thawing procedures on seedling quality in Norway spruce (Picea abies) was evaluated. Freezer-stored seedlings were thawed rapidly for 20 h by immersion in water with an initial water temperature of 8°C or thawed more slowly by gradually increasing the temperature in storage over a period of 8 weeks. Seedlings from these treatments were also compared with seedlings thawed rapidly overnight at 15°C. Frost tolerance, carbohydrate content and the time of bud break were used as indicators of the vitality of the seedlings. Seedlings thawed rapidly in water or air showed significantly better frost tolerance after storage than slowly thawed seedlings. The contents of sucrose and raffinose in seedlings thawed rapidly were also significantly higher than in seedlings thawed more slowly. Bud break occurred later in seedlings thawed rapidly than in slowly thawed seedlings. Rapid thawing in water may be a good method to ensure the delivery of high-quality thawed seedlings throughout the planting season. 相似文献
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Gyorffy S Rodriguez-Lecompte JC Woods JP Foley R Kruth S Liaw PC Gauldie J 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2005,19(1):56-63
Canine malignant melanoma (CMM) is a common and aggressive form of cancer in dogs. Established therapeutic approaches such as surgery, chemotherapy, and radiation therapy (RT) have not proven curative. As a coadjuvant of RT and to enhance the antimelanoma immune response, we characterized dendritic cells (DCs) from the bone marrow (BM) of dogs with CMM, ex vivo, for use in therapeutic vaccines. BM mononuclear cells from 3 dogs with melanoma and from 1 healthy dog were cultured for 12 days in media supplemented with recombinant human granulocyte-macrophage colony stimulating factor, stem cell factor, tumor necrosis factor, and Flt-3 ligand. On day 11, DCs were transduced with an adenovirus vector encoding a xenoantigen, human melanoma antigen gp100. Each dog received 3 subcutaneous vaccinations over a 4-month period. Phenotypic analysis of the expanded DC population demonstrated expression of CD11c/CD18 and major histocompatibility complex class II surface markers, and ultrastructural features characteristic of DCs were observed on electron microscopy. On functional analysis, these DCs were able to stimulate allo-reactivity and capture and express gp100. One dog demonstrated antigen-specific cytotoxic T lymphocyte (CTL) activity in peripheral blood lymphocytes. This dog has displayed no clinical signs, either locally or systemically, of recurrent melanoma 48 months after initial DC injection. However, another dog, which was CTL negative, relapsed 22 months after vaccination. Ex vivo DC expansion is feasible for immunotherapy of spontaneous cancers in outbred dogs. 相似文献
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Abdellah Akhkha Donald D. Clarke Peter J. Dominy 《Physiological and Molecular Plant Pathology》2003,62(6):347-354
The relative levels of tolerance of two wild barley lines (Hordeum spontaneum), B19909 and I-17-40, and one cultivated barley (Hordeum vulgare), cv. Prisma, to Blumeria graminis f.sp. hordei were determined by comparing the effects of different levels of infection on the photosynthesis and respiration rates of the third leaf. Infection caused the early onset of senescence in all three lines, and in particular in cv. Prisma, and was accompanied by decreases in gross and net photosynthesis rates, increases in respiration rates, and loss of chlorophyll. The onset of senescence occurred at approximately the same time in infected leaves of the two wild lines, but once triggered, photosynthesis rates and chlorophyll levels declined more rapidly in I-17-40 than in B19909. A burst of respiratory activity accompanied the onset of senescence, and this was greatest in cv. Prisma. Conidial production was higher in B19909, indicating a higher level of tolerance in this line. 相似文献
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抗逆调节转录因子CBF1基因提高多年生黑麦草的抗旱能力 总被引:16,自引:0,他引:16
通过逆境诱导型启动子rd29B为驱动,分别构建出含有抗逆调节转录因子CBF1基因的表达载体pBAC122,pBAC127,其中pBAC127以CaMV35S启动子驱动的bar基因作为选择标记。用高压氦气基因枪PDS1000/He分别将表达载体导入多年生黑麦草(Lolium perenne)品种Topgun的幼胚、成熟胚和愈伤组织。经除草剂Bialaphos抗性筛选和植株再生,获得了36棵转基因植株。经PCR,Dot-blotting的分子检测,CBF1基因已整合到多年生黑麦草部分转基因株系的基因组中。用5种不同浓度的除草剂涂抹黑麦草叶片,非转基因植株表现为不抗,而转基因植株最高可以抗到135~200 mg/L。叶片脯氨酸含量测定表明,经干旱处理或使用15%PEG处理,转基因植株叶片脯氨酸含量比未处理时显著提高,部分转基因植株提高幅度明显高于非转基因植株。经过25 d人工温室干旱处理,有3棵植株显示出存活迹象,复水后,有1棵植株(C122-7)恢复正常生长。从而表明,利用逆境诱导型启动子(rd29B)来调控外源CBF1基因的表达,能显著改良黑麦草的抗旱能力。 相似文献
86.
北方冷季型草坪草耐盐能力的测定 总被引:7,自引:0,他引:7
本项研究以我国北方地区硫酸盐-氧化物盐土主要含有的Na2SO4和NaCl对冷季型草坪草3个属的10个品种进行萌发期耐盐能力的评比,确定了测试品种种子发芽时耐盐的临界值,并依值的大小将耐盐性从强到弱进行排序,结果是:早熟禾品种以优异、梅里安和塞伯3个品种耐盐性较强,匍匐紫羊茅和匍茎翦股颖两品种的耐盐性强于细弱翦股颖和早熟禾各个品种。对主要建坪种的早熟禾品种在较重盐渍土壤(平均全盐含量0.617%)上进行了小区种植耐盐鉴定。通过对早熟禾6个品种在单位盐浓度上的盖度、地上、地下、植物量、草坪质量评比记分和萌发期耐盐能力的综合评比,筛选出评用质量化,耐盐能力强的品种是:优异、梅里安和爱肯尼。 相似文献
87.
不同品种谷子对单嘧磺隆的耐药性研究 总被引:4,自引:0,他引:4
对34个品种谷子进行盆栽试验,研究单嘧磺隆茎叶处理对谷子安全性的影响。测定相关生理生化指标,通过聚类分析比较不同品种谷子之间的耐药性的差异。聚类分析结果为四大类,10%单嘧磺隆(0.05 mL.m-2)对第一类品种谷子的SOD酶活性有所抑制,使第二类品种谷子的光合速率下降,第三类品种谷子的可溶性糖含量提高,第四类品种谷子的POD酶活性增加。晋谷20号、拖地黄对单嘧磺隆的耐药性较强,丝儿杏、承谷8号、吨谷对单嘧磺隆的耐药性较差。 相似文献
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[目的]探讨土培条件下东南景天矿山与非矿山生态型植物对Cd耐性和富集能力的差异。[方法]采用土培盆栽的方法,以向水稻土中加入不同量的镉作为处理,研究东南景天两种生态型植物在不同镉含量土壤中的生长反应以及体内镉含量与积累量变化。[结果]两种生态型植物对土壤中不同含量Cd的生长反应不同,矿山生态型对土壤Cd的耐受阈值为300 mg/kg,非矿山生态型为50 mg/kg。矿山生态型地上部最大Cd含量为893 mg/kg,根部最大Cd含量为344 mg/kg;而非矿山生态型地上部和根部最大Cd含量分别为124和212 mg/kg。矿山生态型地上部Cd含量大于根部Cd含量,而非矿山生态型根部Cd含量大于地上部。矿山生态型地上部Cd积累量最大值为151.67μg/株;而非矿山生态型为11.99μg/株。两种生态型植物相比较,在相同Cd处理水平下,矿山生态型地上部Cd含量和Cd积累量均显著高于非矿山生态型。[结论]矿山生态型东南景天对土壤Cd的耐受和富集能力显著大于非矿山生态型。从植物对土壤镉的耐性、地上部与根部Cd含量及其比值来看,矿山生态型东南景天是一种Cd超积累植物。 相似文献