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101.
MAGNETIC RESONANCE IMAGING OF THE EQUINE METACARPOPHALANGEAL JOINT: THREE-DIMENSIONAL RECONSTRUCTION AND ANATOMIC ANALYSIS 总被引:1,自引:1,他引:0
Mark J. Martinelli DVM MS Igor V. Kuriashkin PhD Bridget O. Carragher PhD Robert B. Clarkson PhD Gordon J. Baker BVSc PhD MRCVS 《Veterinary radiology & ultrasound》1997,38(3):193-199
Magnetic resonance imaging was used to examine the equine metacarpophalangeal joint. Thirty-two saggital images generated by partial volume imaging were transferred to a computer for three dimensional reconstruction and analysis. All the tissues constituting the metacarpophalangeal joint were readily identified. The most significant increase finding regarded the soft tissues on the palmar aspect of the metacarpophalangeal joint and their interactions with the proximal sesamoid bones. the equine metacarpophalangeal joint has not previously been evaluated using 3-dimensional imaging software. 相似文献
102.
103.
Plant sterol and stanol esters were separated on a Luna hexyl-phenyl column using a gradient of acetonitrile (90-100%) in water. The eluted compounds were detected by atmospheric pressure chemical ionization (APCI)-mass spectroscopy (MS) in the positive mode. Sterol and stanol esters produced [M + H - HOOCR](+) ions. Application of the hyphenated technique-LC-MS-allowed differentiation between a number of esters of sitosterol, campesterol, stigmasterol, and (tentatively) avenasterol, as well as sitostanol and campestanol esters. With cholesteryl decanoate used as the internal standard, the method showed good linearity, precision, and reproducibility. The method required minimal sample pretreatment and can be applied to samples with high water content (juices) as well as samples with high oil content (margarine spreads). The method could be useful for the analysis of sterol and stanol esters in fortified food products. 相似文献
104.
Igor Grebenščikov 《Genetic Resources and Crop Evolution》1970,18(1):17-22
Zusammenfassung Bei zweijährigen Beobachtungen von einfachen F1- und F2-Maisbastarden bezüglich der durch Fritfliegenbefall verursachten Schäden zeigten sich die F2-Bastarde im Durchschnitt der Versuchsgruppen und Jahreswiederholungen signifikant stärker geschädigt als die Eltern (
), und diese signifikant stärker als die heterotischen F1-Bastarde. Der Inzuchtgrad der Eltern übte keinen wesentlichen Einfluß auf diese Reihenfolge aus. Die Bekämpfung der Fritfliege mit Wofatox in einem der Versuchsjahre hat die Reihenfolge in der Befallsstärke ebenfalls nicht geändert, obwohl der Grad der Schädigung im allgemeinen in diesem Jahre bedeutend niedriger wurde. In jedem Falle also zeigten die F2-Bastarde die stärksten Schäden. Bei keinem der anderen geprüften Merkmale wurde solch eigenartiges Verhalten der F2-Generation beobachtet.
On an extreme case of disadvantage of F2 hybrids in comparison with the parents in maize when attacked by the frit fly
Summary In maize, two years observations were made on the damage caused by the Frit fly (Oscinella frit L.) in single cross F1 and F2 hybrids as well as in their parents ( ). In the average of trial groups and years, the F2 hybrids proved most damaged, i. e., significantly more than the parents ( ), and these again significantly more than the heterotic F1 hybrids. The inbreeding degree of the parents did not exert remarkable influence upon this sequence. Also the application of the insecticide Wofatox against the Frit fly in one of the years, although decreasing considerably the extent of damage in general, did not change this sequence of damage. The F2 hybrids showed therefore the highest damage in all cases. Such a peculiar behaviour of F2 hybrids has never been observed for any other character studied.
, , , , ( ), , , . . «» 1966 . , . , , . .相似文献
105.
Igor Grebenščikov 《Genetic Resources and Crop Evolution》1977,25(1):25-31
Zusammenfassung Es wird ein Fall von Hybrideffekt beim Mais beschrieben, in dem eine negative, züchterisch unerwünschte Korrelation bei den Elternformen — zwischen Rohproteingehalt und Kornertrag je Pflanze — sich in der F1 in positive Richtung verschiebt und in dieser Generation sowie in der F2 nicht signifikant von Null verschieden wird oder sogar eine positive Tendenz zeigt. Dasselbe gilt für die negative Korrelation zwischen Rohproteingehalt und Korngröße. Diese heterotische Verbesserung der Korrelation wurde in zweijährigen Versuchen sowohl bei Kreuzungen zwischen schwach ingezüchteten Sortimentsherkünften wie auch bei selektierten Inzuchtlinien beobachtet.
Herrn Prof. Dr. Drs. h. c.Hans Stubbe zum 75. Geburtstag gewidmet.
Für die Rohproteinanalysen sei dem Eiweißlabor von Dr. F.Scholz, für die Verrechnung der Korrelationen der Forschungsgruppe von Dr. A.Meister gedankt. Für die Betreuung der Feldversuche ist der Verf., wie immer, Frl. B.Kohl zu Dank verpflichtet. 相似文献
A positive effect in hybrids as to the correlation between crude protein content and grain yield per plant in maize
Summary A case of heterosis in maize is described, which indicates that a negative, undesirable correlation in the parent forms — between crude protein content and grain yield per plant — is shifted in positive direction in hybrids. In F1 generation as well as in F2 this correlation becomes not significantly different from zero or even shows a tendency to the positive. The same is true of the negative correlation between crude protein content and grain size. This heterotic improvement of the correlations was observed in experiments of two years, with maize collections of low inbreeding degree as well as with selected inbred lines.
( )
, — ( ) — , , . oe , .
Herrn Prof. Dr. Drs. h. c.Hans Stubbe zum 75. Geburtstag gewidmet.
Für die Rohproteinanalysen sei dem Eiweißlabor von Dr. F.Scholz, für die Verrechnung der Korrelationen der Forschungsgruppe von Dr. A.Meister gedankt. Für die Betreuung der Feldversuche ist der Verf., wie immer, Frl. B.Kohl zu Dank verpflichtet. 相似文献
106.
The amount of recycled crust in sources of mantle-derived melts 总被引:5,自引:0,他引:5
Sobolev AV Hofmann AW Kuzmin DV Yaxley GM Arndt NT Chung SL Danyushevsky LV Elliott T Frey FA Garcia MO Gurenko AA Kamenetsky VS Kerr AC Krivolutskaya NA Matvienkov VV Nikogosian IK Rocholl A Sigurdsson IA Sushchevskaya NM Teklay M 《Science (New York, N.Y.)》2007,316(5823):412-417
Plate tectonic processes introduce basaltic crust (as eclogite) into the peridotitic mantle. The proportions of these two sources in mantle melts are poorly understood. Silica-rich melts formed from eclogite react with peridotite, converting it to olivine-free pyroxenite. Partial melts of this hybrid pyroxenite are higher in nickel and silicon but poorer in manganese, calcium, and magnesium than melts of peridotite. Olivine phenocrysts' compositions record these differences and were used to quantify the contributions of pyroxenite-derived melts in mid-ocean ridge basalts (10 to 30%), ocean island and continental basalts (many >60%), and komatiites (20 to 30%). These results imply involvement of 2 to 20% (up to 28%) of recycled crust in mantle melting. 相似文献
107.
低碳氮比对蛋鸡粪与蔗渣好氧堆肥的影响 总被引:2,自引:0,他引:2
通过对低碳氮比(C/N)的蛋鸡粪与蔗渣好氧堆肥研究,旨在探讨充分利用蔗渣资源开展蛋鸡粪资源化利用的现实性与可行性.试验将蛋鸡粪与蔗渣混合制成C/N比值分别为17.88和13.94的两个处理组,好氧堆肥,测定6周堆肥过程中堆体温度、物料C/N、水溶性碳、水溶性氮、铵态氮、硝态氮、全钾、总磷含量的变化.结果表明:2个堆体温度都能快速升至50℃以上,并维持3周,但C/N 17.88组更快升至60℃并在此温度维持时间较长,同时加快了物料铵态氮向硝态氮转化,相对缩短了物料腐熟时间;C/N 13.94组铵态氮较高,pH值也高,N素损失较多,延长了腐熟时间;蔗渣可导致堆肥物料可利用碳少.分析表明,在减少N素损失和提高蔗渣降解率的措施下,低C/N的蛋鸡粪与蔗渣好氧堆肥在生产上具可行性. 相似文献
108.
Stephen G. RistP. Charles Goebel R. Gregory Corace IIIDavid M. Hix Igor Drobyshev Tracy Casselman 《Forest Ecology and Management》2011,262(6):940-946
Although partial cross sections from live trees have been utilized in the development of fire history studies, few efforts have been made to examine the effects of this method on the individual trees that were sampled. We examined 115 red pine (Pinus resinosa Ait.), eastern white pine (Pinus strobus L.), and jack pine (Pinus banksiana Lamb.) trees from which partial cross sections had been removed 2 years earlier, and 209 similarly sized neighboring red pine and eastern white pine trees. Two years following the removal of partial cross sections, 22 sampled trees (19%) had died. When compared with neighboring trees, removing a partial cross section did not appear to increase the mortality rate for a given tree (t-test; P = 0.150). However, when we compared the characteristics of the trees with partial cross sections removed, we did observe some trends; i.e., those trees that died were primarily killed by wind-induced breakage at the level of the partial cross section. Almost all stems where partial cross sections were collected from a catface edge or had >30% of the total area removed were more susceptible to stem breakage and experienced an increased likelihood of mortality. While these results suggest that the collection of partial cross sections from live trees may be an effective method for fire-history sampling, the negative impacts of the sampling on individual trees may be reduced by ensuring that samples are collected from the center, rather than the catface edge, and <25% of the total stem area is removed. 相似文献
109.
Bacteria able to control foot and root rot and to promote growth of cucumber in salinated soils 总被引:1,自引:0,他引:1
Dilfuza Egamberdieva Zulfiya Kucharova Kakhramon Davranov Gabriele Berg Natasha Makarova Tatyana Azarova Vladimir Chebotar Igor Tikhonovich Faina Kamilova Shamil Z. Validov Ben Lugtenberg 《Biology and Fertility of Soils》2011,47(2):197-205
The aim of the present work was to test known bacterial plant growth-promoting strains for their ability to promote cucumber plant growth in salinated soil and to improve cucumber fruit yield by protecting these plants against soil-borne pathogens. Fifty-two plant-beneficial bacterial strains were evaluated for their ability to protect plants against cucumber foot and root rot after bacterization of the seeds and infestation of salinated soil with the isolated Fusarium solani pathogen. Based on the results of initial screenings, five efficient strains were selected, namely Serratia plymuthica RR-2-5-10, Stenotrophomonas rhizophila e-p10, Pseudomonas fluorescens SPB2145, Pseudomonas extremorientalis TSAU20, and P. fluorescens PCL1751. All five strains are salt tolerant since they grow well in a medium to which 3% NaCl was added. Infestation of the soil with F. solani resulted in an increase of the percentage of diseased plants from 17 to 54. Priming of seedlings with the five selected bacterial strains reduced this proportion to as low as 10%. In addition, in the absence of an added pathogen, all five strains showed a significant stimulatory effect on cucumber plant growth, increasing the dry weight of whole cucumber plants up to 62% in comparison to the non-bacterized control. The strains also increased cucumber fruit yield in greenhouse varying from 9% to 32%. We conclude that seed priming with the selected microbes is a very promising approach for improving horticulture in salinated soils. Moreover, allochthonous strains isolated from non-salinated soil, from a moderate or even cold climate, and from other plants than cucumber, functioned as well as autochthonous strains as cucumber-beneficial bacteria in salinated Uzbek soils. These results show that these plant-beneficial strains are robust and they strongly suggest they can also be used successfully in case the climate gets warmer and the soils will become more salinated. Finally, the mechanisms by which they may exert their plant-beneficial action are discussed. 相似文献
110.
Tying knots and linking microscopic loops of polymers, macromolecules, or defect lines in complex materials is a challenging task for material scientists. We demonstrate the knotting of microscopic topological defect lines in chiral nematic liquid-crystal colloids into knots and links of arbitrary complexity by using laser tweezers as a micromanipulation tool. All knots and links with up to six crossings, including the Hopf link, the Star of David, and the Borromean rings, are demonstrated, stabilizing colloidal particles into an unusual soft matter. The knots in chiral nematic colloids are classified by the quantized self-linking number, a direct measure of the geometric, or Berry's, phase. Forming arbitrary microscopic knots and links in chiral nematic colloids is a demonstration of how relevant the topology can be for the material engineering of soft matter. 相似文献