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111.
Alison B. Adams Jennifer Pontius Gillian L. Galford Scott C. Merrill David Gudex-Cross 《Landscape Ecology》2018,33(4):641-658
Purpose
Accurately assessing forest carbon storage on a landscape scale is critical to understanding global carbon cycles and the effects of land cover changes on ecological processes. Calculations of regional-scale forest carbon storage that rely on maps of land cover typically reflect only coarse forest classes. How differences in carbon stored by different tree species may affect such assessments is largely unexplored. We examined a range of forest carbon storage models to understand the effects of forest type specificity on carbon storage estimates in the northeastern United States.Methods
Models estimated forest carbon in total aboveground and coarse root biomass based on three levels of forest classification specificity: (1) relative basal area by species, (2) species associations, and (3) broad forest types per IPCC (in: IPCC guidelines for national greenhouse gas inventories, IPCC, Japan, 2006) guidelines.Results
The specificity of forest type classifications influenced results with generally lower carbon storage estimates resulting from higher-specificity forest classifications. The two most specific models, with mean carbon storage estimates of 103–107 Mg/ha, were most accurate compared to field validation points. These estimates are greater than 2013 field-based U.S. Forest Service estimates (84–90 Mg/ha).Conclusions
There are many sources of uncertainty in landscape-scale carbon storage assessments. Here we show that improving detail in one of these sources, forest stand composition, increases the accuracy of these assessments, and better reflects carbon storage patterns across heterogeneous landscapes. While more work is needed, particularly to improve stand age maps, this information can inform the interpretation of current carbon storage estimates and improve future estimates in heterogeneous forests.112.
An 11-year-old female domestic shorthair cat with a previous history of having been spayed, presented with signs of abdominal distension, lethargy and anorexia of 1 week's duration. On the basis of radiological and ultrasonographic findings a tentative diagnosis of pyometra was made. Exploratory coeliotomy revealed a 900 degrees left horn uterine torsion along the longitudinal axis. Ovariohysterectomy was performed without correction of the torsion. To the authors' knowledge this is the first case report of uterine torsion in a non-gravid cat. 相似文献
113.
IMAGING DIAGNOSIS—A CASE OF SPONTANEOUS HEPATIC PORTAL VEIN GAS IN AN 11‐MONTH‐OLD WEST HIGHLAND WHITE TERRIER 下载免费PDF全文
Jennifer A. Cartwright Craig Breheny Alison C. Major Tracy L. Hill Adam G. Gow 《Veterinary radiology & ultrasound》2016,57(5):E54-E57
An 11‐month‐old female entire West Highland White Terrier presented for chronic diarrhea with acute deterioration in demeanor and progression to systemic inflammatory response syndrome. Transcutaneous abdominal ultrasonography identified colonic ulceration and secondary mucosal gas. Suspected hepatic portal vein gas and hepatic parenchyma gas were also visualized. The patient was stabilized and managed for ulcerative colitis. Based on endoscopic biopsies, the dog was diagnosed with severe, chronic, pyogranulomatous colitis. On repeat ultrasonographic evaluation the portal vein and hepatic gas had resolved but the patient deteriorated and was ultimately euthanized due to sepsis. 相似文献
114.
PILOT STUDY TO ASSESS MEAL PROGRESSION THROUGH THE GASTROINTESTINAL TRACT OF HABITUATED DOGS DETERMINED BY FLUOROSCOPIC IMAGING WITHOUT SEDATION OR PHYSICAL RESTRAINT 下载免费PDF全文
David J. Wrigglesworth Michael Q. Bailey Alison Colyer Kevin R. Hughes 《Veterinary radiology & ultrasound》2016,57(6):565-571
A limiting factor of radiographic contrast studies is the requirement for restraint of the animal in order to reduce movement artifacts. To demonstrate that gastrointestinal transit can be analyzed by a barium meal in nonsedated and unrestrained dogs, a pilot study of six adult Labrador retriever dogs was undertaken. Study subjects were selected by convenience sampling from an available population of Labrador dogs and were trained to stand motionless during radiographic fluoroscopy. Following a meal containing 7% w/w powdered barium sulfate, radiographic images were generated using a digital fluoroscope C‐arm, at intervals of 5, 15, and 30 min, and at 1, 2, 3, 4, 5, 6, 7, and 8 h. A qualitative assessment of fill density using a 5‐point scale was made for the stomach, small intestine, and ascending, transverse, and descending regions of the colon at each timepoint. Gastric emptying half‐time occurred between 1 and 2 h postmeal. Mean fill density of the small intestine increased from 15 min postmeal and reached a peak at 3 h postmeal. Mean fill density of the proximal large intestine mirrored that of the small intestine. The distal large intestine remained empty for the first 2 h postmeal, then increased between hours 2 and 5 postmeal, and was subsequently at maximum fill density from hour 6 postmeal onwards. Fluoroscopic observation of a barium contrast meal provided an effective indication of the amount and progression of ingested food through the various regions of the gastrointestinal tract in habituated, fully conscious dogs. 相似文献
115.
116.
Daniel J. Tolhurst Ky L. Mathews Alison B. Smith Brian R. Cullis 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2019,136(4):279-300
Genomic selection (GS) is a statistical and breeding methodology designed to improve genetic gain. It has proven to be successful in animal breeding; however, key points of difference have not been fully considered in the transfer of GS from animal to plant breeding. In plant breeding, individuals (varieties) are typically evaluated across a number of locations in multiple years (environments) in formally designed comparative experiments, called multi‐environment trials (METs). The design structure of individual trials can be complex and needs to be modelled appropriately. Another key feature of MET data sets is the presence of variety by environment interaction (VEI), that is the differential response of varieties to a change in environment. In this paper, a single‐step factor analytic linear mixed model is developed for plant breeding MET data sets that incorporates molecular marker data, appropriately accommodates non‐genetic sources of variation within trials and models VEI. A recently developed set of selection tools, which are natural derivatives of factor analytic models, are used to facilitate GS for a motivating data set from an Australian plant breeding company. The power and versatility of these tools is demonstrated for the variety by environment and marker by environment effects. 相似文献
117.
118.
Alison M. Hutson Louie A. Toya Douglas Tave 《Journal of the World Aquaculture Society》2012,43(1):84-90
This article describes the initial season‐long yield trial of raising the endangered Rio Grande silvery minnow, Hybognathus amarus, in the conservation rearing facility at the Los Lunas Silvery Minnow Refugium. Ten thousand fish (90,900/ha) were stocked on June 22, 2010. Production was based on a total of 653 mL (5.936 L/ha) of 11‐37‐0 N‐P‐K and 5.5 kg (50 kg/ha) of alfalfa pellets. Fish were harvested in October; almost all were harvested 18–27 October. At stocking, fish averaged 21.7 mm total length and mean weight was 0.10 g. At harvest, fish averaged 48.98 mm and 1.12 g. Fish were sampled monthly, and increased lengths and weights through the study were significant (P = 0.05). Five thousand eight hundred ninety‐two fish were harvested (58.92% survival). Yield was 59.99 kg/ha. Temperature, dissolved oxygen (DO), pH, un‐ionized ammonia, nitrite, turbidity, alkalinity, and chloride were measured at seven sites throughout the outdoor refugium. Secchi disc visibility was measured in the stream and in the ponds. Only two variables (DO and pH) went outside permitted values, but were easily corrected. Harvest was difficult due to the many different naturalized areas consisting of varying depths, channel widths, and substrates. 相似文献
119.