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51.
52.
Sharifah N. Syed Jaafar Johanna Baron Susanne Siebenhandl‐Ehn Thomas Rosenau Stefan Böhmdorfer Heinrich Grausgruber 《Plant Breeding》2013,132(6):546-552
Due to their antioxidant activity, anthocyanins are of increasing interest for nutritionists, food scientists and plant breeders. Anthocyanins in wheat grains are expressed in either the pericarp or aleurone layer. Previous studies revealed that different anthocyanins are present in wheat varieties carrying genes for either the purple pericarp or the blue aleurone trait. Progeny from crosses between red‐, purple‐ and blue‐grained wheat varieties were selected over several cycles for grain colour by visual scoring. Bulked F5 grains were evaluated for their total anthocyanin content by UV‐VIS spectrophotometry and HPLC‐MS. The results demonstrate that it is possible to increase the anthocyanin content by the combination of the different genetic backgrounds for purple pericarp and blue aleurone, even though the majority of progeny were within the range of the purple‐ and blue‐grained check varieties. Visual scoring for grain colour is efficient, reliable and fast for selection in early breeding generations. Advanced breeding lines with high anthocyanin content can be identified by simple extraction methods and spectrophotometric measurements. 相似文献
53.
Martin Kváč Michaela Kestřánová Martina Pinková Dana Květoňová Jana Kalinová Pavla Wagnerová Michaela Kotková Jiří Vítovec Oleg Ditrich John McEvoy Brianna Stenger Bohumil Sak 《Veterinary parasitology》2013,191(3-4):218-227
We describe the morphological, biological, and molecular characteristics of Cryptosporidium pig genotype II and propose the species name Cryptosporidium scrofarum n. sp. to reflect its prevalence in adult pigs worldwide. Oocysts of C. scrofarum are morphologically indistinguishable from C. parvum, measuring 4.81–5.96 μm (mean = 5.16) × 4.23–5.29 μm (mean = 4.83) with a length to width ratio of 1.07 ± 0.06 (n = 400). Oocysts of C. scrofarum obtained from a naturally infected pig were infectious for 8-week-old pigs but not 4-week-old pigs. The prepatent period in 8-week-old Cryptosporidium-naive pigs was 4–6 days and the patent period was longer than 30 days. The infection intensity of C. scrofarum in pigs was generally low, in the range 250–4000 oocysts per gram of feces. Infected pigs showed no clinical signs of cryptosporidiosis and no pathology was detected. Cryptosporidium scrofarum was not infectious for adult SCID mice, adult BALB/c mice, Mongolian gerbils (Meriones unguiculatus), southern multimammate mice (Mastomys coucha), yellow-necked mice (Apodemus flavicollis), or guinea pigs (Cavia porcellus). Phylogenetic analyses based on small subunit rRNA, actin, and heat shock protein 70 gene sequences revealed that C. scrofarum is genetically distinct from all known Cryptosporidium species. 相似文献
54.
MS Faheem I Carvalhais E Baron F Moreira da Silva 《Reproduction in domestic animals》2013,48(5):774-780
This study was performed to evaluate the structural preservation of antral follicles after bovine ovarian tissue vitrification using histological analysis. Ovaries (n = 30) of slaughtered cows were cut into small fragments using a scalpel blade, and the ovarian tissues were randomly assigned to vitrification using 15% dimethyl sulphoxide (DMSO) and 15% ethylene glycol (EG) and fresh tissues (control) groups. For histological evaluations, fresh and post‐thawing ovarian tissues were immediately fixed, serially sectioned into 5‐μm sections and stained with haematoxylin and eosin (H&E). Nine serial sections per fragment were subjected for morphological assessment. The diameter of the antral follicles was determined and classified into four groups: 1 (≤1 mm), 2 (>1–2 mm), 3 (>2–3 mm) and 4 (>3–4 mm). Then, follicular morphology was evaluated in relation to atresia and categorized into seven grades: Grade A (healthy follicle); Grades B, C and D (early atresia); Grades E and F (moderate atresia); and Grade G (advanced atresia). The results revealed that small diameters of antral follicles (1 and 2 mm) were more susceptible for cryoinjury. The normal follicular morphology (Grade A) was not affected by vitrification throughout follicle diameters. Nevertheless, some damage features were monitored after vitrification. In conclusion, the morphological structure of bovine antral follicles could be successfully preserved by ovarian tissue vitrification. 相似文献
55.
Contamination history of suspended river sediments accumulated in oxbow lakes over the last 25 years 总被引:3,自引:2,他引:1
Ondrej Bábek Klára Hilscherová Slavomír Nehyba Josef Zeman Martin Famera Juraj Francu Ivan Holoubek Jirí Machát Jana Klánová 《Journal of Soils and Sediments》2008,8(3):165-176
Background, aims, and scope Embankment of meandering river systems in many industrial areas results in the formation of artificial oxbow lakes that may
act as perennial or intermittent traps for river sediments. Their deposits can be dated using a combination of historical
and stratigraphic data, providing a good means to study historical records of contamination transported by rivers. Contamination
history over the last few decades is of special significance for Central and Eastern Europe as it can reflect high pollutant
levels in the second half of the twentieth century and the subsequent improvement after the fall of the Iron Curtain. The
purpose of this study was to investigate recent sediments of an oxbow lake of the Morava River, Czech Republic, their stratigraphic
records, sediment architecture, and history of contamination.
Materials and methods Seven ground-penetrating radar (GPR) profiles and three sediment cores up to 4 m deep were studied. The stratigraphy of the
cores was inferred from visible-light spectrophotometry, X-ray radiography, grain size analysis, and semiquantitative modal
analysis of sandy fractions. The sediments were dated using the 137Cs mass activity and combinations of stratigraphic and historical data. The cores were sampled for concentrations of heavy
metals and persistent organic pollutants. Wet sampled, lyophilized, and sieved sediments were extracted and analyzed for heavy
metals by inductively coupled plasma mass spectrometry (ICP-MS) of aqua regia leachate and for persistent organic pollutants
by gas chromatography (GC-ECD and GC-MS).
Results Three distinct sedimentary sequences (S1, S2, and S3) were identified. The basal sequence S1 represents river channel sediments
deposited before the formation of the oxbow lake, most likely before the 1930s. The boundary between the S1 and S2 sequence
correlates with the level of sediment dredging from 1981 evidenced from historical data. The overlying sequences S2 and S3
represent a postdredging sediment wedge, which progrades into the lake. 137Cs dating revealed a distinct Chernobyl 1986 peak at ∼150 cm depth inferring sedimentation rates up to 7.7 cm/year. Sediment
contamination abruptly increased from the pre-1930s deposits to the post-1981 deposits. The concentration levels increased
two to five times for Pb, As, Zn, and Cu, about 10 to 15 times for Cr, Sb, and Hg, up to 34 times for Cd, and 25 to 67 times
for DDTs, PCBs, and PAHs. The concentrations of most contaminants remained approximately constant until the late 1980s when
they started to decrease slowly. The decreasing trends were most prominent for heavy metals and anthracene, less prominent
for DDTs, and almost absent for PCBs and most PAHs.
Discussion Different temporal and spatial patterns for various contaminants make it possible to distinguish between anthropogenic point
sources from local industry (anthracene, Cr, Cd), possible diffuse sources (most PAHs), and geological background (V, Co,
Ni, and Mo). The observed recent trends in heavy metal and persistent organic pollutant contamination are generally consistent
with data from other Central European rivers. The roughly balanced contamination levels in sediments from the lake and the
adjacent river channel suggest that the oxbow lake deposits reflect immediate levels of the contamination bound to suspended
particulate matter passing through the river.
Conclusions The investigated oxbow lake accumulated suspended sediment from Morava River, developing a thick sedimentary body. The sediments
offer a good time framework to study historical contamination of the river on a decade time scale. Continuous contamination
trends can be traced back to the early 1980s. The results show that stratigraphic analysis of cores has a good potential for
identification of uninterrupted historical trends and unconformities, e.g., due to dredging.
Recommendations and perspectives Oxbow lakes may provide an alternative to floodplains and reservoir deposits when studying river contamination history. High
sedimentation rates of up to 7.7 cm/year offer a very good stratigraphic resolution, making it possible to study contamination
patterns on annual or even seasonal time scales. On the other hand, oxbow lakes may represent long-term contamination stores,
which are unlikely to be redistributed by river erosion and, hence, may possess significant environmental risks for the farther
future. 相似文献
56.
Honeydew produced by aphids is a well-studied food source for mutualistic ants. Although considerable amounts drop onto the soil surface there are hardly any studies dealing with the potential effects of this additional C source for soil organisms, particularly those living at the soil surface. We studied this question by simulating honeydew and investigating plots under Populus canescens formerly infested with aphids on two ruderal sites differing in soil organic matter content and vegetation cover. The simulated honeydew input increased microbial biomass with some delay in week 10. Both natural and simulated honeydew raised the activity densities of an epigeic Collembola taxon, the Bourletiellidae, but not of the dominant Hemisotoma thermophila. The honeydew effect varied over time and with the site, and was more pronounced at the nutrient-poor site for Collembola, but not for microbial biomass. Ant consumption reduced the amount of honeydew reaching the soil surface by 50%. The activity density of H. thermophila was negatively related to ants and spiders, hinting at a top-down control. Honeydew clearly acts as a bottom-up force for soil organisms, which is however only part of the complex network connecting the food webs of primary producers and decomposers. 相似文献
57.
Stanislav Trdan Jana Čuk Anka Poženel Mojca Bavcon Kralj Mojca Rot Branko Carlevaris 《Acta Agriculturae Scandinavica, Section B - Plant Soil Science》2019,69(2):174-180
Between 2012 and 2014, we tested the efficacy of different synthetic attractants for the purpose of massive trapping of common European cockchafer adults (Melolontha melolontha). The research took place in three different locations in Slovenia (Otlica, ?rni Vrh nad Idrijo, Cesta nad Ajdov??ino) during flight periods of adult beetles. In the period 2013–2014, we used, on the basis of the preliminary test results (2012), the following chemicals: toluquinone, cis–3–hexen–1-ol, ethyl acetate, toluquinone?+?cis–3 hexen–1-ol, and ethanol as a control. M. melolontha adults were most abundant in the location ?rni Vrh nad Idrijo; the traps in this location caught 18 times more of them than those in the first location and more than six times more than those in the third location. Male insects accounted for 73 to 87% of the trapped specimens. We confirmed the highest efficiency of cis–3–hexen–1-ol in 2013 (43.25?±?0.08 males/trap), as well as in 2014 (15.00?±?0.14 males/trap). On the basis of the trapped adult common European cockchafers and the simple economic analysis of applying different synthetic substances for attracting them, we found that independent application of cis-3-hexen-1-ol is the most efficient and cost-effective option for attracting the studied insect pest. Consequently, we recommend it as an attractant in the traps for massive trapping of adult common European cockchafers. 相似文献
58.
59.
Artificial insemination with frozen-thawed spermatozoa is commonly used in cattle breeding. A simple and fast procedure is needed for routine evaluation of the acrosomal status of frozen-thawed bovine sperm. Therefore, the purpose of this study was to test two staining procedures used to determine the viability and integrity of acrosome of frozen-thawed bovine spermatozoa. Double staining and Hoechst/FITC-Pisum sativum agglutinin (FITC-PSA) labelling were tested for evaluating the viability and acrosome reaction induced by calcium ionophore of bull spermatozoa. In our experiments no significant differences were detected in the frequency of acrosome-reacted sperm either by double staining (37.98%) or by FITC-PSA labelling (39.33%). The viability of sperm stained by the double staining method was 67.17%, and a higher portion of viable sperm (82.67%) was observed by staining with the Hoechst procedure (P < 0.01). On the basis of the results obtained it is concluded that both methods can be used for detecting the acrosome reaction of frozen-thawed bovine spermatozoa. 相似文献
60.
G. Romito C. Guglielmini M.O. Mazzarella M. Cipone A. Diana B. Contiero M. Baron Toaldo 《Journal of Veterinary Cardiology》2018,20(5):364-375