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排序方式: 共有480条查询结果,搜索用时 15 毫秒
21.
22.
Feline mammary tumors 总被引:1,自引:0,他引:1
The characteristics of feline mammary cancer--that is, the rapid growth of primary mammary tumors, the high rate of tumor recurrence, and the poor survival statistics--demonstrate the need for (1) early diagnosis of the primary tumor; (2) immediate, aggressive surgical therapy; and (3) frequent follow-up examinations to detect early clinical signs of recurrent disease. A number of factors that influence prognosis have been described. As more information becomes available concerning the behavior of feline mammary tumors and the results of various forms of treatment, more effective protocols can be developed. Continued etiologic research may play a vital role in determining the direction of therapy. 相似文献
23.
Vaidya NA Mathias K Ismail B Hayes KD Corvalan CM 《Journal of agricultural and food chemistry》2007,55(9):3408-3413
The conversion and degradation of malonylglucosides were kinetically characterized under elevated pH/heat conditions. Malonylgenistin and malonyldaidzin were heated at 60, 80, and 100 degrees C and pH values of 8.5, 9, and 9.5. A simple kinetic model was developed, which adequately predicted the conversion and degradation reactions. The conversion and degradation rates increased as temperature and pH increased. The rates of conversion of both malonylglucosides into their respective beta-glucosides were comparable under all pH/heat treatments. However, at 100 degrees C, the rates of degradation of malonyldaidzin were approximately double those of malonylgenistin, under all pH treatments. When malonlydaidzin was heated at 100 degrees C and pH 9.5, degradation of the produced daidzin occurred. Therefore, an alternative kinetic model was developed to better predict the conversion and degradation of malonyldaidzin occurring at 100 degrees C and pH 9.5. The models developed provide soy food manufacturers with guidelines for better control of the profile and level of isoflavones.. 相似文献
24.
Dawn C Hayes Rebecca R Anderson Richard L Walker 《Journal of veterinary diagnostic investigation》2003,15(4):390-394
Accurate identification of the bovine pathogen Tritrichomonas foetus is sometimes complicated by the presence of other trichomonadid protozoa in clinical samples. A highly specific and reproducible approach for differentiating 3 common types of bovine trichomonadid protozoa found in the bovine preputial cavity, T. foetus, Pentatrichomonas hominis, and a Tetratrichomonas species, was developed using polymerase chain reaction (PCR) and restriction fragment length polymorphism (RFLP) analysis. Universal trichomonadid protozoa primers, TFR1 and TFR2, were used to amplify the 5.85 rRNA gene and internal transcribed spacer regions (ITSRs), and the products were digested with the restriction enzyme HpyCH4IV. Restriction fragment length polymorphism analysis was performed on 55 trichomonad isolates from bovine preputial washing and scraping samples. The RFLP results correlated 100% with 5.85 rRNA gene and ITSR sequence resultsand PCR results with primers specific for T. foetus. The results of this study demonstrate that PCR and RFLP analysis can be used in lieu of DNA sequencing to identify the specific trichomonadid protozoa isolated from the bovine preputial cavity. 相似文献
25.
Selection for cold chipping genotypes from three early generations in a potato breeding program 总被引:1,自引:0,他引:1
Chipping potatoes are an important market for the processing industry. Of the traits influencing chip quality,chip color is
market limiting since other traits have diminished value without light chip color. Cold (4 °C) storage can reduce storage losses and cultivars producing light colored chips directly from cold storage are needed for
this reason. Selection for cold chipping cultivars is traditionally practiced by visual evaluation of progeny the first few
years in the field, followed by selection for cold chipping in years 4–5. Early generation selection for cold chipping may
reduce cultivar development time by identifying good chipping progeny, families and parents earlier in the breeding cycle.
Progeny from 175 4x × 4x families were evaluated from three early generations. They were greenhouse grown tubers (GGT) evaluated
after6 mo. storage using randomly selected progeny, and field grown single hills propagated from either seedling transplants
(FTR), or from greenhouse grown tubers (FGT). Progeny from field grown generations were selected first by visual evaluation,
and then by random selection and chipped after6 mo. (visual selections) or 3 and 6 mo. storage (random selections). Cold chipping
progenies were found in all three early generations. The earliest generations for selection are GGT or FTR, but may be less
efficient than FGT. Correlations suggest that reliable parent and family selection is possible using GGT data. Visual selection
eliminated 4/5 of the good chipping progeny, while identifying 8 of 11,714 genotypes combining visual merit and cold chipping
potential. Increased genetic variation and sexual polyploidization are possible strategies for increasing the number of desirable
genotypes.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
26.
The objectives of this research were to determine the individual and interaction effects of the Ppd-H1 and Sh2 loci on agronomic traits under short- and long-photoperiod regimes. Nineteen doubled haploid (DH) lines from the ‘Dicktoo’בMorex’ mapping population, which represented the four genotypes at the Ppd-H1 and Sh2 loci, were pheno-typed in controlled environment photoperiods. Both Ppd-H1 and Sh2 had significant effects on several agronomic traits, in addition to their role in determining first node appearance and flowering time. The magnitude of these effects depended on daylight. Under long-day conditions (18 h) Ppd-H1, and under short-day conditions (12 h) Sh2 was a significant determinant of most characters. The interactions between these two loci were significant for several characters, particularly for yield components, under both long- and short-photoperiod regimes. Under the long-day treatment, Ppd-H1 influenced plant height through the determination of node number. There was an epistatic association between the two loci for both 1000-kernel weight and tillering. The combination of photoperiod insensitivity and vernalization requirement caused a significant increase in tillering. This was paralleled by a decrease in 1000-kernel weight. Under the long-day treatment, neither Ppd-H1 nor Sh2 influenced plant yield. Under short-day conditions, the combination of photoperiod insensitivity and vernalization requirement had a pronounced negative effect on plant yield. 相似文献
27.
B Swaminathan P S Hayes V A Przybyszewski B D Plikaytis 《Journal of the Association of Official Analytical Chemists》1988,71(3):664-668
We compared selective enrichment broths used by the U.S. Food and Drug Administration (FDA) and the U.S. Department of Agriculture (USDA), Food Safety and Inspection Service, for their efficiency in the quantitative recovery of Listeria monocytogenes from a naturally contaminated Brie cheese that was obtained as part of an epidemic investigation. Quantitative recovery of Listeria in FDA broth (greater than 2.4 x 10(5) colony forming units/mL) was significantly better than recovery in USDA broth (9.3 x 10(3) colony forming units/mL). When USDA broth was supplemented with D-glucose and Phytone (papaic digest of soy protein), its recovery efficiency improved but did not equal that of FDA broth for isolating L. monocytogenes from Brie cheese. A comparison of 4 selective plating media [modified McBride's agar, gum base nalidixic acid agar, lithium chloride-phenylethanol-moxalactam agar (LPM), and acriflavine-ceftazidime agar (AC)] showed that 3 L. monocytogenes strains belonging to serotype 1/2a were partially or completely inhibited on LPM and AC agars. One strain of serotype 1/2a formed microcolonies on modified McBride's agar after 48 h of incubation. 相似文献
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Sutton T Baumann U Hayes J Collins NC Shi BJ Schnurbusch T Hay A Mayo G Pallotta M Tester M Langridge P 《Science (New York, N.Y.)》2007,318(5855):1446-1449