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71.
[目的]分析盐藻DNA对水稻幼苗在低盐中生长的影响。[方法]将刚萌发的水稻幼苗根系浸入5 mg/L盐藻DNA溶液中培养2d,以蒸馏水培养为对照,处理后的水稻幼苗栽于含有氯化钠3 g/L的MS培养液中培养,分析盐藻DNA对水稻幼苗在低盐中生长的影响。[结果]水稻幼苗用5 mg/L盐藻DNA处理后,在含氯化钠3 g/L的MS培养液中培养15 d,其平均株重为150.7 mg,比对照增加了10.3%;平均株高为15.28 cm,比对照增加了6.1%;平均存活率为45.0%,比对照增加了125.0%;平均根数为7.15条,比对照减少了2.8%;平均根长为3.83 cm,比对照缩短了8.4%。说明盐藻DNA提高了水稻幼苗的耐盐适应性。[结论]盐藻DNA可提高水稻的耐盐适应性。 相似文献
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73.
Drought is one of the most important environmental constraints limiting plant growth, development and crop yield. Many drought-inducible genes have been identified by molecular and genomic analyses in ... 相似文献
74.
P. Van Dijk C. Cuperus 《European journal of plant pathology / European Foundation for Plant Pathology》1989,95(6):343-356
When testing the response of species of the genusNicotiana to 14 isolates of potato viruses A (PVA), X (PVX) and Y (PVY) and tobacco mosaic virus (TMV), sections and section parts of the genus could be divided into five groups according to the overall reaction of their species. Species from arid regions of australia and belonging to the sectionSuaveolentes (subgenusPetunioides) were most sensitive and least resistant, whereas the sectionsPaniculatae (subgenusRustica),Tomentosae (Tabacum) andNoctiflorae (Petunioides) appeared least sensitive and most resistant. Sixty-one percent of the accessions of the latter sections proved resistant to at least two of the viruses. The most resistant species have their main geographical distribution in the central Andes (southern Peru, Bolivia and north-western Argentina), where the viruses may have originated. One other resistant species wasN. africana (Suaveolentes) indigenous to south-western Africa. The most sensitive American sections, viz.Genuinae (Tabacum) andTrigonophyllae, Alatae, Acuminatae andBigelovianae (Petunioides), were generally more sensitive than species of theSuaveolentes section from outside the arid regions of Australia. The remaining part of the genus, viz. the American sectionsThyrsiflorae andRusticae (Rustica) andUndulatae, Repandea andNudicaules (Petunioides) was intermediate between the latter group ofSuaveolentes species and the resistant group of sections with regard to sensitivity and resistance, but had a high rate of tolerance to PVA, PVX and PVY and of hypersensitivity-associated resistance to TMV. The results indicate that the viral respons in the genusNicotiana is mainly determined geographically and to a lesser extent taxonomically.Samenvatting Na inoculatie van een grote collectieNicotiana-soorten met 14 isolaten van de aardappelvirussen A (PVA), X (PVX) en Y (PVY) en tabaksmozaïekvirus (TMV), konden de secties of sectiedelen van het genus op basis van de gemiddelde reactie van hun soorten in vijf groepen worden verdeeld. Soorten uit Australische woestijngebieden en taxonomisch behorend tot de sectieSuaveolentes (subgenusPetunioides) bleken het meest gevoelig en het minst resistent, terwijl de sectiesPaniculatae (subgenusRustica),Tomentosae (Tabacum) enNoctiflorae (Petunioides) het minst gevoelig en het meest resistent waren. Van de collectienummers van de laatstgenoemde secties bleek 61% resistentie tegen minstens twee van de virussen te bezitten. De meest resistente soorten hebben hun verspreidingsgebied vooral in het centrale deel van het Andesgebergte (het zuidelijk deel van Peru, Bolivia en noord-westelijk Argentinië). Mogelijk is dit het ontstaansgebied van deze virussen. De einge andere resistente soort wasN. africana (Suaveolentes) uit zuid-westelijk Afrika. De meest gevoelige Amerikaanse secties, te wetenGenuinae (Tabacum) enTrigonophyllae, Alatae, Acuminatae enBigelovianae (Petunioides), waren gemiddeld gevoeliger danSuaveolentes-soorten die niet uit de Australische woestijnen afkomstig zijn. Het resterende deel van het genus, bestaande uit de Amerikaanse sectiesThyrsiflorae enRusticae (Rustica) enUndulatae, Repandae enNudicaules (Petunioides), stond met betrekking tot gevoeligheid en resistentie tussen laatstgenoemd deel van de sectieSuaveolentes en de groep resistente secties in, maar vertoonde in hoge mate tolerantie voor PVA, PVX en PVY en met overgevoeligheid samengaande resistentie voor TMV. Uit de resultaten blijkt dat de reacties van het genusNicotiana op virussen vooral geografisch bepaald zijn en in mindere mate taxonomisch. 相似文献
75.
油菜菌核病抗(耐)病性筛选方法的研究 总被引:10,自引:2,他引:10
本文评价了不同接种鉴定方法在油菜菌核病抗(耐)病性筛选上的应用。结果表明:花期离体或活体叶片菌丝体接种和限期接种法能显著区分不同品种(系)的抗感水平;苗期菌丝体悬浮液接种和试管苗接种法适于早期育种世代进行大规模筛选。对83份品种(系)鉴定结果,821、083等呈轻度感病,大部分属中感至高感范围。 相似文献
76.
Young adult sheep were dosed with extracts of Narthecium ossifragum plants by the oral or parenteral routes and the resulting nephrotoxicity was assessed from the increases in the concentrations of creatinine and urea in the serum. Following single intraruminal or intraperitoneal doses of extracts derived from 30 g N. ossifragum (wet weight) per kg live weight (kg lw), serum creatinine concentrations increased from about 100 mol/L to between 260 and 510 mol/L. The serum urea concentrations increased from about 5–8 mmol/L to between 11 and 66 mmol/L in individual sheep. Daily intraruminal administration of 5–30 g/kg lw to three sheep over a 10- or 15-day period increased creatinine concentrations from 100 mol/L to 300–760 mol/L, and urea concentrations from 5–8 mmol/L to 35 mmol/L. A single intraperitoneal challenge dose of 30 g/kg lw, delivered 7 or 12 days after the final intraruminal dose, did not lead to increased serum creatinine or urea concentrations, indicating that oral treatment had apparently resulted in an increased tolerance to the nephrotoxic principle(s) in N. ossifragum. 相似文献
77.
Only limited and contrasting information is available about the metabolic fate in cattle of fumonisin B1, a mycotoxin produced by moulds of Fusarium. This study was carried out to evaluate the hepatic metabolism of fumonisin B1 by bovine liver microsomes. No biodegradation or metabolization of the mycotoxin by liver microsomes was detectable after incubating fumonisin B1 with bovine microsomes in the presence of a regenerating system for 1 h. No aminopolyol 1, aminopolyol 2 or aminopentol, metabolites of fumonisin B1, were detected in any of the incubated samples. The tolerance of ruminants to fumonisin B1 is apparently not dependent on its detoxification in the rumen. 相似文献
78.
Diclofop-methyl resistance was evaluated in populations of Italian ryegrass ( Lolium multiflorum Lam.) infected and uninfected with fungal endophyte ( Neotyphodium ). Survival was tested in susceptible populations using herbicide screening. The results served as inputs to a model for investigating the role of endophyte infection in the evolution of L. multiflorum resistance to herbicide. The tolerance of infected plants varied depending on the origin of the population and the herbicide dose. Only in some populations and at some diclofop-methyl doses did plants infected with these endophytes have higher survivorship than endophyte-free plants. The model demonstrated that endophytes might indeed play an important role in the evolution of herbicide-resistant weeds, delaying the appearance of herbicide resistance. 相似文献
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80.
对11份引自俄罗斯的野生无芒雀麦(Bromus inermis Leyss.)材料,在0.3%、0.4%、0.5%NaCl胁迫下,通过存活率、总生物量、叶片伤害率、株高的测定,采用隶属函数法和标准差系数赋予权重法进行耐盐性综合评价。结果表明:供试11份无芒雀麦在0.3%、0.4%、0.5%NaCl胁迫下存活率分别为90%~100%,76.7%~96.7%,67.0%~96.7%;根据耐盐性综合评价值(D)得出供试材料耐盐性顺序为,ZXY04P-371>ZXY04P-255>ZXY04P-136>ZXY04P-188>ZXY04P-96>ZXY04P-503>ZXY04P-34>ZXY04P-322>ZXY04P-241>ZXY04P-46>ZXY04P-18。 相似文献