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11.
Sticky cotton causes severe processing problems at textile mills and can be caused by plant sugars deposited directly from
the plant to the lint in the absence of insects. A partial diallel design was used to investigate the combining ability of
six upland cotton, Gossypium hirsutum L., genotypes in Lubbock, Texas. Sucrose and glucose on fibers were measured as well as more mechanical fiber properties including
stickiness ratings. Variance component analysis indicated significant differences among genotypes for all fiber traits and
for sugar content. The greatest differentiation occurred in samples taken from more immature fruiting forms. Moreover, significant
GCA and SCA differences were determined among parental lines for fiber traits including stickiness ratings. Findings suggest
that breeding efforts could be directed toward lines with a low likelihood of producing sticky cotton. 相似文献
12.
Molly B Haffey Randal D Pairan Paul R Reinhart Monica A Stoops 《Journal of zoo and wildlife medicine》2008,39(3):349-357
This study reports urinalysis values for three species of captive rhinoceros (Rhinoceros unicornis, Dicerorhinus sumatrensis, and Diceros bicornis) and evaluates individual and species differences. Repeated urinalysis was conducted on 11 individuals to establish normal reference ranges. Although no individual or species differences existed in urinary values for pH, all species differed in specific gravity. Rhinoceros urine demonstrated many physical and chemical properties similar to that of the horse, but reliability of this comparison was limited. Urinary pH in the rhinoceros was within range of that established for the horse and other large herbivores. However, all rhinoceros species exhibited urinary specific gravities below the lower limit of the normal equine reference range. Comparative urinalysis using an outside laboratory source confirmed the results of this study and illustrated the value of conducting in-house analysis. These results are the first data available on reference ranges for urine parameters in the greater one-horned, Sumatran, and African black rhinoceros and provide a useful diagnostic tool for the veterinary care of individuals in captivity. 相似文献
13.
Ariel M. Bagg 《Irrigation and Drainage Systems》2000,14(4):301-324
Hydraulic engineering projects in ancientAssyria (nowadays, northern Iraq) have beenwitnessed for many centuries, from the end ofthe second to the middle of the firstmillennium BC. The use of both philologicaland archaeological evidence enables us toreconstruct the different stages of thehydraulic enterprises in Assyria, as well asthe specific terminology used in this fieldof technological knowledge. The Assyriankings changed the location of their capitalseveral times, either by founding newcities or by converting older settlementsinto royal residences. Establishment ofthese new capitals included theconstruction of canal systems, whichbrought water drawn from rivers or thesurrounding mountains to irrigate theirfields and gardens. This paper focuseson these projects and reviews their mainfeatures. It also points out themethodological difficulties encounteredwhen using the available sources. 相似文献
14.
Abstract— The reproductive cycle of two subspecies of surfclams, Spisula solidissimu solidissima and Spisulu solidissimu similis , cultured under similar nursery and field conditions were examined. Monthly gonadal examination showed that S. s. similis initiated gametogenesis, achieved mature status, and spawned earlier than S. s. solidissimu. S. s. similis spawned from January to June, while S. s. solidissimu spawned in May. S. s. similis exhibited an equal sex ratio; whereas, S. s. solidissima had significantly more males than females (1.00 M: 0.32 F). Implications for aquaculture development of surfclams are discussed. 相似文献
15.
Regions of strong coupling between soil moisture and precipitation 总被引:26,自引:0,他引:26
Koster RD Dirmeyer PA Guo Z Bonan G Chan E Cox P Gordon CT Kanae S Kowalczyk E Lawrence D Liu P Lu CH Malyshev S McAvaney B Mitchell K Mocko D Oki T Oleson K Pitman A Sud YC Taylor CM Verseghy D Vasic R Xue Y Yamada T;GLACE Team 《Science (New York, N.Y.)》2004,305(5687):1138-1140
Previous estimates of land-atmosphere interaction (the impact of soil moisture on precipitation) have been limited by a lack of observational data and by the model dependence of computational estimates. To counter the second limitation, a dozen climate-modeling groups have recently performed the same highly controlled numerical experiment as part of a coordinated comparison project. This allows a multimodel estimation of the regions on Earth where precipitation is affected by soil moisture anomalies during Northern Hemisphere summer. Potential benefits of this estimation may include improved seasonal rainfall forecasts. 相似文献
16.
The efficacy of narasin in the control of necrotic enteritis (NE) was investigated in a floor pen study of 2000 broiler chickens using a Clostridium perfringens feed inoculum challenge model. Treatments were 1) nonmedicated, nonchallenged; 2) nonmedicated, challenged; 3) narasin, nonchallenged; 4) narasin, challenged. Narasin was administered at 70 ppm in the feed from day 0 to trial termination on day 41. Challenge inoculum contained approximately 1 x 10(8) colony-forming units CP/ml and was administered from day 14 to day 16. In the unmedicated groups, challenged birds had significantly (P < 0.05) lower mean body weight and reduced feed efficiency at day 21 and significantly (P < 0.01) higher cumulative NE mortality at day 41 compared with unchallenged. Similarly, among unmedicated birds, those challenged had a significantly (P < 0.01) higher mean NE score on day 17 and significantly (P < 0.05) higher mean huddling scores on days 15-17 than unchallenged. Among challenged birds, those fed narasin had significantly (P < 0.05) higher mean body weight and improved feed efficiency at days 21 and 41 and significantly (P < 0.01) lower cumulative NE mortality at day 41 than unmedicated. Similarly, among challenged birds, those receiving narasin had a lower mean NE score on day 17 (P > 0.05) and significantly (P < 0.05) lower huddling scores on days 16 and 17 than unmedicated. Coccidiosis lesion scores were zero for birds euthanatized from all treatment groups on day 17, suggesting that the beneficial effects of narasin were not due to prevention of coccidiosis. This study thus provides evidence that narasin is effective in the prevention of necrotic enteritis in broiler chickens. 相似文献
17.
Boyce M Bryant KF Jousse C Long K Harding HP Scheuner D Kaufman RJ Ma D Coen DM Ron D Yuan J 《Science (New York, N.Y.)》2005,307(5711):935-939
Most protein phosphatases have little intrinsic substrate specificity, making selective pharmacological inhibition of specific dephosphorylation reactions a challenging problem. In a screen for small molecules that protect cells from endoplasmic reticulum (ER) stress, we identified salubrinal, a selective inhibitor of cellular complexes that dephosphorylate eukaryotic translation initiation factor 2 subunit alpha (eIF2alpha). Salubrinal also blocks eIF2alpha dephosphorylation mediated by a herpes simplex virus protein and inhibits viral replication. These results suggest that selective chemical inhibitors of eIF2alpha dephosphorylation may be useful in diseases involving ER stress or viral infection. More broadly, salubrinal demonstrates the feasibility of selective pharmacological targeting of cellular dephosphorylation events. 相似文献
18.
19.
Stahl RS Custer TW Pochop PA Johnston JJ 《Journal of agricultural and food chemistry》2002,50(4):732-738
A method using a deuterated surrogate of the avicide 3-chloro-p-toluidine hydrochloride (CPTH) was developed to quantify the CPTH residues in the gastrointestinal (GI) tract and breast muscle tissues in birds collected in CPTH-baited sunflower and rice fields. This method increased the range of a previous surrogate/gas chromatography/mass spectroscopy method from 0-2 to 0-20 microg/g in tissue samples and greatly simplified the extraction procedure. The modified method also sought to increase recoveries over a range of matrix effects introduced by analyzing tissues from birds collected in the field, where the GI tract contents would be affected by varying diet. The new method was used to determine the CPTH concentration in GI tract samples fortified with CPTH-treated rice bait to simulate the consumption of varying amounts of treated bait by two nontargeted bird species, pigeon (Columbia livia) and house sparrow (Passer domesticus). The new method was then used to examine the CPTH concentrations in the gizzard contents of the targeted bird species, red-winged black bird (Agelaius phoeniceus) and brown-headed cowbird (Molothrus ater), that were collected after feeding at a treated bait site. The method proved sufficiently sensitive to quantify CPTH in the breast muscle tissues and the gizzard contents of red-winged blackbirds and brown-headed cowbirds during an operational baiting program. The levels of CPTH determined for these birds in both tissue samples were determined to be highly correlated. The appearance of CPTH in the breast muscle tissue immediately after feeding was not anticipated. The potential secondary hazard posed by the targeted birds to potential scavengers and predators was also evaluated. 相似文献
20.
Growth and survival of white sturgeon larvae were examined at ad libitum feeding with three commercial salmonid diets, and experimental crustacean diet, and a live food control (cubifex). The results demonstrated that some manufactured diets, particularly a semi-moist ration, can be used to rear white sturgeon during the first 40 days of feeding. Although specific growth rates of fish fed a semi-moist feed were 40% lower than those fed live foods, survival rates were similar. The high mortality previously associated with later transfer of fish from live foods to manufactured diets was avoided. Dry diets were not well accepted and resulted in lower rates of growth and survival. 相似文献