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541.
Jaruwan Kampa Karl Ståhl Lena HM Renström Stefan Alenius 《Acta veterinaria Scandinavica》2007,49(1):7
Background
Bovine viral diarrhoea virus (BVDV) is an important pathogen in cattle. The ability of the virus to cross the placenta during early pregnancy can result in the birth of persistently infected (PI) calves. These calves shed the virus during their entire lifespan and are the key transmitters of infection. Consequently, identification (and subsequent removal) of PI animals is necessary to rapidly clear infected herds from the virus. The objective of this study was to evaluate the suitability of a commercial Erns-capture ELISA, in comparison to the indirect immunoperoxidase test (IPX), for routine diagnostic detection of BVDV within a control programme. In addition, the effect of passive immunity and heat-inactivation of the samples on the performance of the ELISA was studied. 相似文献542.
G. Schwarz M. Herz X. Q. Huang W. Michalek A. Jahoor G. Wenzel V. Mohler 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2000,100(3-4):545-551
Genetic mapping and the selection of closely linked molecular markers for important agronomic traits require efficient, large-scale
genotyping methods. A semi-automated multifluorophore technique was applied for genotyping AFLP marker loci in barley and
wheat. In comparison to conventional 33P-based AFLP analysis the technique showed a higher resolution of amplicons, thus increasing the number of distinguishable
fragments. Automated sizing of the same fragment in different lanes or different gels showed high conformity, allowing subsequent
unambigous allele-typing. Simultaneous electrophoresis of different AFLP samples in one lane (multimixing), as well as simultaneous
amplification of AFLP fragments with different primer combinations in one reaction (multiplexing), displayed consistent results
with respect to fragment number, polymorphic peaks and correct size-calling. The accuracy of semi-automated co-dominant analysis
for hemizygous AFLP markers in an F2 population was too low, proposing the use of dominant allele-typing defaults. Nevertheless, the efficiency of genetic mapping,
especially of complex plant genomes, will be accelerated by combining the presented genotyping procedures.
Received: 10 April 1999 / Accepted: 11 May 1999 相似文献
543.
We have recently isolated from bovine adrenal medulla a novel C-terminally amidated opioid peptide, amidorphin, which derives from proenkephalin A. Amidorphin revealed a widespread distribution in bovine, ovine, and porcine tissue. Particularly high concentrations of amidorphin immunoreactivity were detected in adrenal medulla, posterior pituitary, and striatum, similar to the major gene products of proenkephalin A. In the adrenal medulla of each species, authentic amidorphin was the predominant immunoreactive form. Pituitary and brain, however, contained predominantly putative N-terminally shortened fragments of amidorphin of a slightly lower molecular weight and shorter retention times on HPLC. In addition, in ovine adrenal medulla, a putative high-molecular-weight form of amidorphin was detected. These findings are indicative of a tissue-specific processing of the proenkephalin A precursor, leading predominantly to authentic amidorphin in the adrenal medulla and further processing to smaller C-terminal fragments in the brain and pituitary. 相似文献
544.
545.
LoVo, a continuous cell line derived from a human colon carcinoma produces two alkaline phosphatases: the heat-labile, L-homoarginine-insensitive, intestinal form, characteristic of its tissue of origin and the heat-stable, term-placental form, ectopically produced by a variety of tumors. Under basal conditions the activity levels of both enzymes are similar. Hyperosmolality and sodium butyrate induce increased levels of activity of the two alkaline phosphatases in a disparate fashion; whereas hyperosmolality augments the activity of both to the same extent, the effect of butyrate is more pronounced on the activity of the intestinal enzyme. When the two inducers are combined, induction of term-placental alkaline phosphatase is additive and that of the intestinal enzyme is synergistic. The effect of hyperosmolality is blocked by cycloheximide, and induction by sodium butyrate is inhibited by thymidine, cordycepin and cycloheximide. The known alkaline phosphatase inducer, prednisolone, has no effect on the enzymes of LoVo cells. Our results suggest that in these tumor cells the activity levels of the closely homologous term-placental and intestinal alkaline phosphatases appear to be independently controlled. 相似文献
546.
Walter Vichnewski Ilda Kazumi Shuhama Richard C. Rasanske Werner Herz 《Phytochemistry》1976,15(10):1531-1532
The eudesmanolides granilin and ivasperin were isolated from Ambrosia polystachya DC. 13C-NMR spectra are reported for these and other naturally-occurring ring A-hydroxylated isoalantolactones. 相似文献
547.
The whole plant extract of Inula thapsoides afforded seven new structurally related guaianolides. The structures and stereochemistry were determined by spectroscopic methods, particularly one- and two-dimensional NMR spectroscopy, and extensive NOE experiments. 相似文献
548.
The isolated rat vas deferens, being insensitive to morphine, contains selective binding sites for β-end-orphin. A half-maximal inhibition of twitch tension evoked by electrical stimulation is established with 100 nM β-endorphin, while fragments of β-endorphin, that is, methionine-enkephalin, α- and γ-endorphin, are almost ineffective. The opiate alkaloid etorphine, a powerful inhibitor of guinea-pig ileum and mouse vas deferens, is 100-fold less potent on the rat vas deferens. The unique β-endorphin activity suggests very specific binding sites for this peptide, which cannot be related to the μ- or δ-receptors so far described for opiods on isolated preparations. 相似文献
549.
The known chemistry of subtribe Eupatoriinae, tribe Eupatorieae, Asteraceae, is reviewed critically and taxonomic implications are discussed. 相似文献
550.