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Tizzotti MJ Sweedman MC Tang D Schaefer C Gilbert RG 《Journal of agricultural and food chemistry》2011,59(13):6913-6919
A novel, fast, and straightforward procedure is presented for the characterization of starch (the largest energy component in food) and modified starches (such as octenyl succinic anhydride (OSA)-modified starches used as a dispersing agent in the food industry). The method uses (1)H NMR to measure the degree of branching and also, for modified starches, the degree of chemical substitution. The substrate is dissolved in dimethyl-d(6) sulfoxide; addition of a very low amount of deuterated trifluoroacetic acid (d(1)-TFA) to the medium gives rise to a shift to high frequency of the exchangeable protons of the starch hydroxyl groups, leading to a clear and well-defined (1)H NMR spectrum, which provides an improved way to determine the degrees of both branching and chemical substitution. Measurements of the size and molecular weight distributions by multiple-detector size exclusion chromatography show that degradation by TFA does not affect the accuracy of the method. 相似文献
35.
Marcio Rocha Francelino Carlos Ernesto G.R. Schaefer Felipe Nogueira Bello Simas Elpídio Incio Fernandes Filho Jos Joo Lelis Leal de Souza Liovando Marciano da Costa 《CATENA》2011,85(3):194-204
The main pedological, geomorphological and cryogenic features of Keller Peninsula, part of Admiralty Bay, King George Island, Maritime Antarctica, were mapped and quantified with emphasis on the relationship between the ice retreat process, melt-out, landform development and soil distribution. Moraines, protalus, scree slopes, inactive glacial cirques, uplift marine terraces, biogenic landforms, arêtes and Felsenmeer were mapped. Scree slope is the main landform, covering approximately 25% of the peninsula, indicating prominent paraglacial features. Inherited, glacial landforms, such as lateral moraines, highland plateau and exhumed U shaped-valleys, are now being exposed in north Keller by ice shrinkage of former ice protecting cover. Landforms influenced soil formation and stability. Cryosols and Leptosols (WRB) roughly corresponding to Gelisols and Entisols (SSS), respectively, are the most common soil classes, with an overall tendency of absent permafrost in the coastal areas, changing to sporadic permafrost at mid-slope, and discontinuous permafrost with greater altitude and substrate stability. 相似文献
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Neeru Narula Prof. Dr BS Saharan Vivek Kumar Ranjana Bhatia LK Bishnoi BPS Lather 《Archives of Agronomy and Soil Science》2013,59(1):69-77
High nitrogen fixing, phosphate solubilizing, phytohormones producing isolates of Azotobacter, Azospirillum, Acetobacter and Pseudomonas were used as inoculants for cotton. Important cultures were selected on the basis of their effect on root/shoot length and chemotactic behaviour. Selected bioinoculants were earlier tested for their beneficial properties like nitrogen fixation (ARA), ammonia excretion, IAA production etc. These bio-inoculants were further tested for phosphate solubilization property. Various chosen strains were tested with Desi (HD 123) and American (H 1098) cotton under field conditions (as for wheat). Plant height and boll weight were determined at the time of harvesting whereas survival rate of inoculated bacteria was determined after 30, 80 and 130 days respectively. In the year 2000–01, on the basis of boll number and boll weight plant?1 AVK 51 (36; 76.2?g plant?1), HT 57 (27; 56.9?g plant?1), AC18 (33; 61.5?g plant?1), Ala 27 (36; 61.4?g plant?1) and Pseudomonas (34; 71.3?g plant?1) were identified as significant both for American and desi cotton varieties. Highest survival rate was observed with Mac 68 (33.4 × 105) followed by HT54 (31.5 × 105) after 30 days of sowing, which decreased after 80 days and remained constant up to 130 days. This trend was observed with all the cultures. Similar results were observed in 2001–02. 25?kg ha?1 N saving was observed with A. chroococcum (AVK51) bioinoculant for cotton crop. 相似文献
37.
Mylne Auger Constance Fazio Marie de Swarte Genevive Bussires Deanna Schaefer Cary M. Springer 《Veterinary radiology & ultrasound》2019,60(6):717-728
Ultrasonography and radiography are standard diagnostic tests for cats with suspected splenic disease, however published information on outside sources of variation are currently lacking. The purpose of this prospective, randomized, crossover group study was to evaluate effects of common sedative drugs on the sonographic and radiographic characteristics of the spleen in healthy cats. Fifteen healthy adult research cats were randomly assigned into one of three groups corresponding to different sequences of administration of five sedative drugs/drug combinations (acepromazine; butorphanol; dexmedetomidine; midazolam and butorphanol (MB); and dexmedetomidine, butorphanol, and ketamine (DBK)), administered at 1‐week intervals. At each visit, three‐view abdominal radiographic and ultrasonographic examinations were performed prior to sedation and repeated 15‐30 min and 2‐3 h post sedation. Two board‐certified radiologists (one ACVR and one ACVR/ECVDI) evaluated the anonymized and randomized images. Acepromazine resulted in significantly increased sonographic and radiographic splenic measurements from baseline, which remained significantly increased 2‐3 h post sedation. The mean magnitude of this change ranged from 0.9 mm (tail height, SD 1.4 mm) to 1.8 mm (body height, SD 1.7 mm) for ultrasound, and was 2.2 mm (ventrodorsal width, SD 2.3 mm) for radiographs. With butorphanol, there was no significant change in splenic size. For dexmedetomidine, MB, and DBK, there was a trend toward increased splenic size from baseline to the first post‐sedation timepoint, which was statistically significant for radiographic measurements, although not for ultrasound. Findings indicated that acepromazine should be avoided prior to imaging while butorphanol may be used when sedation is needed in cats presenting for potential splenic disease. 相似文献
38.
Carine K. Souza Daiane P. Oldiges Ana Paula S. Poeta Itabajara da S. Vaz Rejane Schaefer Danielle Gava Janice R. Ciacci‐Zanella Cludio W. Canal Luís G. Corbellini 《Zoonoses and public health》2019,66(1):125-132
Backyard pig populations are not monitored for influenza A virus (IAV) in Brazil and there are limited data about seroprevalence and risk factors in these populations. Our goal was to assess possible factors associated with IAV seroprevalence in backyard pig populations using an indirect ELISA protocol based on a recombinant nucleoprotein. Following the IAV screening using NP‐ELISA, subtype‐specific serology based on hemagglutination inhibition (HI) assay of the ELISA‐positive pigs was conducted. The survey comprised a total of 1,667 sera samples collected in 2012 and 2014 in 479 holdings and the estimated seroprevalence was 5.3% (3.84%–7.33%) and 2.3% (1.34%–3.71%) in the respective years. In both years, H1N1pdm09 was the most prevalent subtype. The multivariable analysis showed main factors such as “age,” “sex,” “number of suckling pigs” and “neighbours raising pigs” that presented the greatest effect on IAV seroprevalence in these pig populations. These factors may be associated with the low biosecurity measures and management of backyard holdings. In addition, the low IAV seroprevalences found in these backyard pig populations could be related to a low number of animals in each pig holding and low animal movement/replacement that do not favour IAV transmission dynamics. This low frequency of H1N1pdm09 seropositive pigs could also be due to sporadic human‐to‐pig transmission of what is now a human seasonal influenza A virus; however, these factors should be explored in future studies. Herein, these results highlight the importance of IAV continued surveillance in backyard pig holdings, since it is poorly known which IAVs are circulating in these populations and the risk they could pose to public health and virus transmission to commercial farms. 相似文献
39.
Patsy Alldredge Melissa Gutierrez David Duvernell Jacob Schaefer Paul Brunkow Wilfredo Matamoros 《Ecology of Freshwater Fish》2011,20(4):513-521
Abstract – Movement and dispersal patterns are key biological processes across a range of organisational levels. The Fundulus notatus species complex includes several species with similar ecological niches that exhibit broadly overlapping ranges. We conducted a mark–recapture study on two of the most widely distributed members of this species complex to improve our understanding of their movement and habitat use. A population of F. notatus was studied between June and August of 2008 and 2009 in Cahokia Creek, a small tributary of the Mississippi River in Illinois, along with a parallel study of Fundulus olivaceus between May and July of 2009 in Big Creek, a tributary of the Pascagoula River in Mississippi. Fish were recaptured approximately weekly, and habitat variables were measured. Estimated daily movement rates varied significantly both between locations and between years. Fundulus olivaceus in Big Creek moved <1 m per day, while F. notatus in Cahokia Creek in 2009 moved nearly 23 m per day. The distribution of movements was strongly leptokurtic in all three data sets. Differences in movement rates were attributed to significant differences in population size and habitat characteristics. Our data did not support the hypothesis that populations consist of distinct mobile and resident components. Instead, individual fish went through periods of little or no movement followed by extensive movement (consistent with the home range shift model of fish movement). We discuss the implications these results have for contact zone dynamics between these two species. 相似文献
40.
Meyer-Luehmann M Coomaraswamy J Bolmont T Kaeser S Schaefer C Kilger E Neuenschwander A Abramowski D Frey P Jaton AL Vigouret JM Paganetti P Walsh DM Mathews PM Ghiso J Staufenbiel M Walker LC Jucker M 《Science (New York, N.Y.)》2006,313(5794):1781-1784
Protein aggregation is an established pathogenic mechanism in Alzheimer's disease, but little is known about the initiation of this process in vivo. Intracerebral injection of dilute, amyloid-beta (Abeta)-containing brain extracts from humans with Alzheimer's disease or beta-amyloid precursor protein (APP) transgenic mice induced cerebral beta-amyloidosis and associated pathology in APP transgenic mice in a time- and concentration-dependent manner. The seeding activity of brain extracts was reduced or abolished by Abeta immunodepletion, protein denaturation, or by Abeta immunization of the host. The phenotype of the exogenously induced amyloidosis depended on both the host and the source of the agent, suggesting the existence of polymorphic Abeta strains with varying biological activities reminiscent of prion strains. 相似文献