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781.
Graf TN Levine KE Andrews ME Perlmutter JM Nielsen SJ Davis JM Wani MC Oberlies NH 《Journal of agricultural and food chemistry》2007,55(4):1205-1211
Populations of bloodroot [Sanguinaria canadensis L. (Papaveraceae)] are found throughout the eastern forests of North America, with particular abundance in the southern Appalachian Mountains. Increasingly, it is finding use in Europe as a nonantibiotic animal feed supplement to promote weight gain. As efforts to cultivate this herb are underway, there is a need to understand the effect of agronomic permutations on both the dry mass rhizome yield and the yield of benzophenanthridine alkaloids. Month-to-month variability of the concentration of the alkaloids sanguinarine and chelerythrine in both cultivated and wildcrafted bloodroot was examined. The alkaloid yield was consistently higher, but more variable, in wildcrafted plants. On average, cultivated rhizomes were both larger and more consistently sized than those that were wildcrafted. The concentration of a suite of trace elements was measured in soil that was collected concomitantly with each plant accession. Differences in element profiles were compared against alkaloid yields. 相似文献
782.
Margaret E. Montgomery Lynn M. Woodworth David A. Briscoe 《Biological conservation》2010,143(8):1842-1849
Many threatened species are being maintained in captivity to save them from extinction, often with the eventual aim of reintroduction. The objective of genetic management in captivity is to ‘freeze’ evolution i.e. to avoid genetic adaptation to captivity and to retain genetic diversity. Most current genetic management of threatened species addresses the latter, but does not explicitly address the former. The theory underlying current genetic management and its practical implementation assumes neutrality of loci. However, genetic adaptation in captive populations may cause non-neutral behavior at neutral loci due to selective sweeps (hitchhiking) caused by rapid allele frequency changes at linked fitness loci. We compared changes in microsatellite genetic diversity at eight non-coding loci with neutral predictions in 23 pedigreed captive populations of Drosophila melanogaster maintained with effective sizes of 25 (eight replicates), 50 (6), 100 (4), 250 (3) and 500 (2) for 48 generations. Loss of microsatellite heterozygosity was significantly faster (by 12%) than predicted by neutral theory, as assessed by regressing proportion of heterozygosity retained on pedigree inbreeding coefficients. Further, greater than neutral changes were observed for both variances in allele frequencies across replicates (by 25%), and for temporal changes in allele frequencies (by 33%). All eight microsatellite loci showed signals of selectively-driven changes. Rather than having their evolution ‘frozen’, captive populations are undergoing major genome-wide selective sweeps that affect not only fitness loci but linked neutral loci. Captive genetic management for threatened species destined for reintroduction requires modification to explicitly minimize genetic adaptation to captivity. 相似文献
783.
Robert L. Magaletta Suzanne N. DiCataldo Dong Liu Hong Laura Li Rajendra P. Borwankar Margaret C. Martini 《Cereal Chemistry》2010,87(4):363-369
The glycemic index (GI) is an indicator of the relative human glycemic response to dietary carbohydrates in a food. It is determined using a costly and time‐consuming in vivo method. We describe an in vitro analytical method that allows the accurate prediction of the GI of a food product. The method involves digestion of the food product using HCl and enzymes, followed by HPLC analysis of sugars and sugar alcohols. Data from the HPLC analysis combined with the product's compositional information are treated using an artificial neural network to produce a predicted value for the GI of the food product. For the sample set examined (n = 72) consisting of a variety of food types, r2 = 0.93 and the root mean square error of correlation (RMSEC) = 5 GI units. Twenty‐fold cross‐validation yields CVR2 = 0.89, indicating good predictive ability for samples outside the calibration set. The relative standard deviation of the method is 6.6%. This method is rapid and low cost relative to in vivo testing. Due to good ability to predict in vivo GI, it may be a valuable screening tool for determining the relative effect of food ingredients on the glycemic index of a food product. 相似文献
784.
Margaret C. McEntee DVM Rodney L. Page DVM MS G. Neal Mauldin DVM Donald E. Thrall DVM PhD 《Veterinary radiology & ultrasound》2000,41(6):554-556
Thirteen dogs with infiltrative lipomas were treated with cobalt 60 radiation. Four of the thirteen dogs also received either whole body (n = 2) or combination local/whole body (n = 2) hyperthermia in conjunction with radiation therapy. Cytoreductive surgery was performed prior to radiation in 10 dogs, although only 3 dogs had microscopic disease at the time of radiation therapy. Dogs received a total dose of 45.6 Gy-63 Gy in 2.5-4 Gy/fraction on either a Monday/Wednesday/Friday schedule or on a daily Monday through Friday schedule. Twelve of the 13 dogs had computed tomography (CT) images acquired prior to irradiation. Survival time was determined from the time of completion of radiation therapy. Survival ranged from 6 months to 94 months, with a median (95% confidence interval) of 40 (18.5-77) months and a mean of 46.4 months. Only one dog was euthanized due to persistent signs related to the infiltrative lipoma at 6 months after the end of radiation therapy. There was no apparent difference in response based on whether or not the dogs received hyperthermia in conjunction with irradiation, although the numbers were too small to make any significant conclusions. It appears that dogs with infiltrative lipomas can benefit from external beam irradiation alone or in combination with surgery to effect long-term local tumor control. 相似文献
785.
Soumesh K. Padhi Isaiah Tolo Margaret McEachran Alexander Primus Sunil K. Mor Nicholas B. D. Phelps 《Journal of fish diseases》2019,42(11):1609-1621
Koi herpesvirus (KHV; cyprinid herpesvirus‐3) and carp oedema virus (CEV) are important viruses of common and koi carp (Cyprinus carpio); however, the distribution of these viruses in wild common carp in North America is largely unknown. During the summers of 2017 and 2018, 27 mass mortalities of common carp were reported from four states in the USA (Minnesota, Iowa, Pennsylvania and Wisconsin), the majority of which were distributed across eight major watersheds in southern Minnesota. Samples from 22 of these mortality events and from five clinically healthy nearby carp populations were screened for KHV, CEV and SVCV using real‐time polymerase chain reaction (qPCR). KHV was confirmed in 13 mortality events, CEV in two mortality events and coinfections of KHV/CEV in four mortality events. Nucleotide sequence analysis revealed that the KHV and CEV detected here are closely related to European lineages of these viruses. While molecular detection alone cannot conclusively link either virus with disease, the cases described here expand the known range of two important viruses. This is also the first reported detection of KHV and CEV coinfections in wild carp populations. 相似文献
786.
787.
Margaux Vallée Xikun Lu Joan Oñate Narciso Wenhui Li Yuyue Qin Margaret A. Brennan Charles S. Brennan 《Plant foods for human nutrition (Dordrecht, Netherlands)》2017,72(3):301-307
Black ear mushroom (Auricularia auricula) is an important genus of cultivated mushroom, which contains health benefits. Incorporating black ear (BE) mushroom into brown rice by extrusion changed the physicochemical, and more importantly, the nutritional characteristics of the extrudates. With increased incorporation of BE mushroom in the extrudates in vitro starch digestion of the different extrudates revealed significantly reduced starch digestion, suggesting a lower glycaemic index. In addition, incorporation of BE in brown rice extrudates increased the total phenolic concentration of the samples, which led to higher % scavenging effect against free-radicals in DPPH assay. In the ORAC assay for anti-oxidant activity, BE powder exhibited the highest anti-oxidant activity, followed by 10% BE and 15% BE, and 5% BE extruded products. The extruded brown rice control exhibited the lowest antioxidant activity. Inclusion of black ear mushroom was shown to improve the nutritional qualities of the food product illustrating the connection between plant bioactive ingredients and human health. 相似文献
788.
Exploring the microbial diversity of the distal intestinal lumen and mucosa of farmed rainbow trout Oncorhynchus mykiss (Walbaum) using next generation sequencing (NGS) 下载免费PDF全文
Philip P Lyons James F Turnbull Karl A Dawson Margaret Crumlish 《Aquaculture Research》2017,48(1):77-91
In this study, next generation sequencing (NGS) was used to survey the 16S rRNA ribotypes of the distal intestinal lumen and mucosal epithelium of farmed rainbow trout. This approach yielded a library consisting of 2 979 715 quality filtered paired sequences, assigned to genus level of taxonomy using the Ribosomal Database Project (RDP). A high level of diversity was observed in both regions. A total of 90 bacterial genera were identified in the lumen of all fish sampled, compared with 159 in the mucosa. The allochthonous microflora was dominated by sequences belonging to the γ Proteobacteria (mean sequence abundance 54.3%), in particular the Enterobacteriaceae, with Yersinia, Serratia, Hafnia and Obesumbacterium the most abundant genera. Fewer γ Proteobacteria (mean sequence abundance 37%) were present in the mucosa, and autochthonous communities consisted of a more even split among the bacterial classes, with increases in sequences assigned to members of the β Proteobacteria (mean sequence abundance 18.4%) and Bacilli (mean sequence abundance 16.8%). The principal bacterial genera recorded in the mucosa were Cetobacterium, Yersinia, Ralstonia, Hafnia and Carnobacterium. The results of this study demonstrate that the luminal and mucosal bacterial communities may be different in their respective structures, and that the mucosal microflora of rainbow trout may be more diverse than previous research has suggested. This research also demonstrated a degree of conservation of bacterial genera between individual fish sampled, and is to the author's knowledge the first time the MiSeq® NGS platform has been used to explore the rainbow trout intestinal microflora. 相似文献
789.
Effects of low‐level dietary microalgae supplementation on the distal intestinal microbiome of farmed rainbow trout Oncorhynchus mykiss (Walbaum) 下载免费PDF全文
Philip P Lyons James F Turnbull Karl A Dawson Margaret Crumlish 《Aquaculture Research》2017,48(5):2438-2452
In this study, high throughput 16S rRNA sequencing was used to investigate the effect of a novel whole‐cell dietary microalgae meal (Schizochytrium limacinum), on the distal intestinal microbiome of farmed rainbow trout, Oncorhynchus mykiss. Heterotrophic microalgae are rich in omega 3 polyunsaturated fatty acids, can be produced sustainably and have been shown to have beneficial effects on host health. After a 15‐week trial period, microbial community profiles were compared between the distal intestinal contents of fish fed either a control diet or a treatment diet that partially replaced fish oil with microalgae meal, at a substitution level of 5%. The results of this research showed that the microbial communities of both fish populations were composed of similar microbial taxa, however, the treatment group fed the microalgae supplement possessed a greater level of microbial diversity than those in the control group. A limited number of bacterial taxa were discriminatory between diets and were significantly elevated in the treatment group, notably operational taxonomic units (OTUs) assigned to the genera Streptococcus, Leuconostoc, Lactobacillus, Lactococcus and Weissella. However, the overall structure of the intestinal microbiome between control and treatment groups was not found to be significantly different. The treatment group displayed a heavier mean weight and condition factor at the end of the trial period. The results of this study suggest that the tested microalgae meal can be used as a replacement for a proportion of fish oil in aquafeeds, with minor changes to the intestinal microbiome of farmed rainbow trout, and positive effects on growth. 相似文献
790.
Margaret E Schmuckler Aldos C Barefoot Daniel A Kleier Daryl P Cobranchi 《Pest management science》2000,56(6):521-532
Vapor pressure values for agricultural chemicals are necessary for estimating volatilization and dissipation through transport in the vapor phase. The low vapor pressures of the sulfonylurea herbicides have presented significant challenges in vapor pressure determination. We have used the Knudsen gas effusion method at elevated temperatures and extrapolated to 25 °C. Along with the Knudsen method, computer calculations using the Grain equation were also used to estimate vapor pressure. The gas saturation method with quantitation by high performance liquid chromatography (HPLC) provided an upper limit that confirmed the low vapor pressures obtained using Knudsen gas effusion and computer calculations. We report the best available experimental results for the vapor pressures of sulfonylurea herbicides. © 2000 Society of Chemical Industry 相似文献