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131.
132.
Common beans (Phaseolus vulgaris) are separated into two distinct groups: Andean and Middle American. We identified CAL 143 as the first Andean bean with resistance to angular leaf spot disease caused by Phaeoisariopsis griseola. Angular leaf spot is the most widespread and economically important bean disease in southern and eastern Africa, and it is especially severe on the extensively grown Andean beans. Cal 143 was resistant in Malawi, South Africa, Tanzania, and Zambia, but it was susceptible in Uganda. This was attributed to the presence of races of P. griseola in Uganda not present in the other countries. We identified two additional Andean bean lines, AND 277 and AND 279, with resistance to angular leaf spot in Malawi. We also characterized the virulence diversity of 15 isolates of P. griseola from southern and eastern Africa into nine different races. Five of six isolates from Malawi and two of seven from Uganda, obtained from large-seeded Andean beans, were characterized into four different races considered Andean. These were compatible only or mostly with large-seeded Andean cultivars. The other eight isolates from Uganda, Malawi, and the Democratic Republic of Congo, obtained from a small- or medium-seeded Middle American beans, were characterized into five different Middle American races. These were compatible with Middle American and Andean cultivars. CAL 143 was resistant or intermediate under greenhouse conditions to all but one of the same 15 isolates from southern and eastern Africa, but it was susceptible to an isolate from Uganda obtained from a medium-seeded Middle American bean. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
133.
Three flocks of Japanese quail, approximately 75,000 birds each, experienced acute high mortality beginning at 24 to 28 days of age. Gross lesions were absent or were composed of either multifocal small pale areas on livers and spleens or lungs slightly darker in color than normal. Histopathology revealed multifocal splenic and hepatic necrosis and interstitial pneumonia. Pasteurella multocida, serotype 3,4, was isolated from affected tissues. The quail were successfully treated with chlortetracycline, and the organism was apparently eliminated from the premises by thorough cleaning, disinfection, and insect and rodent control. Experimental studies showed Japanese quail to be highly susceptible to disease caused by the P. multocida isolated from the affected flocks.  相似文献   
134.
A blind, placebo-controlled study evaluated the effects of ursodeoxycholic acid (UDCA) given orally, at a dose of 15 mg kg−1 per day for eight weeks, on the physical condition, haematological and serum biochemical profiles, urinalysis, total serum bile acids ( ) and hepatic histology of four healthy cats. There were no clinically important significant differences between the groups or within the treatment groups in clinicopathological parameters, concentrations or histology. A significant lower concentration/proportion of taurochenodeoxycholic acid was observed in the treated cats (P=0·05). Only one treated cat accumulated measurable quantities of , and the compound appeared to be non-toxic. It did not, increase the concentration of , and accumulated minimally in the serum. It should be investigated for therapeutic use in cats with hepatobiliary disease.  相似文献   
135.
One-day-old poults were placed on contaminated litter on which poults previously had developed an enteric disease characterized by diarrhea, increased mortality, and stunting. These exposed birds were examined for clinical signs and pathologic changes in bone and parathyroid glands compared with controls. Intestinal and fecal samples were examined for potential pathogens. Exposed poults varied in size as early as day 8 and had significantly decreased weight gains and reduced shank lengths on days 8, 12, 16, and 21. The proximal tibial growth plate was narrowed. The mineralized hypertrophy zone was decreased in length and contained multiple non-mineralized bands on days 8, 12, 16, and 21. Metaphyseal trabeculae were reduced in amount on days 16 and 21. Parathyroid glands were hyperplastic on days 16 and 21. The bone and parathyroid gland lesions indicated that mineral homeostasis was being maintained at the expense of the skeleton during the enteric disease. A specific etiology for the enteric disease was not determined. Cryptosporidium, rotavirus, paramyxovirus, and Salmonella were identified in the exposed poults, and paramyxovirus and Salmonella were identified in the controls.  相似文献   
136.
Day-old broiler chicks were fed a vitamin D-deficient diet for 30 days. Gross, microscopic, and radiographic examinations of the proximal tibiotarsus were done at 2, 3, and 4 weeks of age. In 2-week-old chicks, there was variable lengthening and disorganization of the proliferating-prehypertrophied zone (P-PHZ), resorption of cartilage spicules in the degenerating hypertrophied zone and primary spongiosa, and lengthening of bone spicules in the secondary spongiosa; many bone surfaces were lined with increased osteoid. In 3-week-old chicks, there was a tendency for the P-PHZ to decrease in relative length and for cartilage spicules to increase in length. In 4-week-old chicks, however, there was marked lengthening of the P-PHZ, resorption of cartilage spicules, and replacement of the metaphysis with irregularly oriented islands of woven bone, osteoid, and loose fibrous connective tissue.  相似文献   
137.
The discovery of the Comstock Lode near Virginia City, Nevada, in 1859 resulted in the construction of more than 30 stamp-mills along Sixmile Canyon and its tributaries to process the gold and silver ore. Extraction of the precious metals from the ore was accomplished using a crude mercury (Hg) amalgamation process. As a result, a substantial quantity of Hg was released along with tailings materials to this tributary of the Carson River. During the past 134 years, Hg-contaminated sediments have been eroded from the mill sites and transported downstream by fluvial processes, thereby expanding the influence of Hg pollution. Geomorphic and geochemical data have been combined in this study to document the distribution, quantity, and physical dispersal of Hg-contaminated materials from Sixmile Canyon to the Carson River. These data show that the influx of Hg to the Carson River has varied through time as a function of the erosional and depositional processes operating on the Sixmile Canyon Alluvial Fan located between the canyon and the Carson River channel; relatively high influx rates to the river occurred immediately after mining began and from approximately 1933 to 1948. Hg-polluted sediments are located within discrete areas of the fan and comprise about 21 % of the total active and relict fan surface. Mass balance calculations estimate that about 31,500 kg of Hg, 18,200 oz of An, and 1,205,800 oz of Ag are contained within 710,700 m3 of contaminated materials. If site remediation is conducted, extraction of An and Ag, which is worth about $12 million at current market prices, would greatly defray the costs of clean-up activities. The study also illustrates that the effects of Hg may be temporally and spatially displaced from the period and location of milling activities. Thus, we conclude that to accurately assess the site for remediation, an understanding of the spatial and temporal variations in geomorphic dispersal processes is required.  相似文献   
138.
Innate immunity provides frontline antiviral protection and bridges adaptive immunity against virus infections. However, viruses can evade innate immune surveillance potentially causing chronic infections that may lead to pandemic diseases. Porcine reproductive and respiratory syndrome virus (PRRSV) is an example of an animal virus that has developed diverse mechanisms to evade porcine antiviral immune responses. Two decades after its discovery, PRRSV is still one of the most globally devastating viruses threatening the swine industry. In this review, we discuss the molecular and cellular composition of the mammalian innate antiviral immune system with emphasis on the porcine system. In particular, we focus on the interaction between PRRSV and porcine innate immunity at cellular and molecular levels. Strategies for targeting innate immune components and other host metabolic factors to induce ideal anti-PRRSV protection are also discussed.  相似文献   
139.
The performance of silver perch fed a commercially available diet based on meat meal (38%), grain legumes (18%), oilseeds (10%), wheat millrun (20%), fishmeal (5%) and fish oil (3%) was compared with experimental diets based on alternative protein sources in two experiments. In Experiment 1, two experimental diets contained similar contents of fishmeal and fish oil as the commercially available reference diet, but soybean (25%) and wheat millrun (>31%) were used to reduce animal protein meals by approximately 50%. The digestible protein and digestible energy of the two experimental diets was either slightly lower (31.5% and 12.8 MJ kg?1) or slightly higher (34.9% and 14.3 MJ kg?1) than the reference diet (32.1% and 13.2 MJ kg?1). In Experiment 2, the two experimental diets contained no fishmeal but included higher amounts of rendered animal meals (41–48%). One of the diets had similar digestible protein to the reference diet (32%) while the other had only 25% digestible protein. Silver perch (38 g for Experiment 1 and 59 g for Experiment 2) were stocked into each of nine 0.1 ha earthen ponds with fish in three ponds fed each diet for 191 days (Experiment 1) or 187 days (Experiment 2). Survival was >94% in all ponds in both experiments. In Experiment 1, growth rates and feed conversion ratios (FCRs) ranged from 2.1 to 2.4 g fish?1 day?1 and 1.7 to 1.9 respectively. Growth rates were significantly (P<0.05) lower for fish fed the experimental diet with the lowest digestible energy content. Growth rates for fish fed the other experimental diet and the reference diet were similar (P>0.05). In Experiment 2, growth rates and FCRs ranged from 2.3 to 2.4 g fish?1 day?1 and 1.6 to 1.7. There were no significant differences in fish performance indices for any of the three diets although experimental power was low (power=0.31). A blind consumer sensory evaluation (taste panel) of fish fed the three diets in Experiment 2 rated fish as ‘highly acceptable’. The diet with the lowest digestible protein content produced the best fish in terms of ‘smell liking’, ‘flavour liking’, ‘muddy flavour strength’ and ‘fresh flavour strength’. These results confirm that soybean meal and/or rendered animal protein ingredients including meat meal and poultry offal meal, and wheat can form the basis for high‐performance, low‐cost diets for intensive pond culture of silver perch.  相似文献   
140.
Two-hectare unsown, tilled fallow plots put in place under agri-environment schemes for stone curlews Burhinus oedicnemus in England were surveyed for other bird species, brown hares Lepus europaeus, carabid beetles, vascular plants, butterflies and bumblebees. The results were compared with those from surveys within the crop in the same field and in neighbouring fields. This was done to test whether agri-environment management targeted at a single species also provided benefits to wider biodiversity. All groups except carabid beetles were more abundant, more likely to be recorded, or more species rich on plots than within the crop. Carabid beetle activity–density and species richness did not differ between the plot and the crop; activity–density of one functional group (predators) was lower on plots than in the crop. Six rare arable plant species were recorded, predominantly from plots, and the plots are considered to perform comparably to other agri-environment options available in England designed specifically for arable plants. One red-listed bird species of conservation concern (skylark Alauda arvensis) was more abundant on plots than in the crop, and three other red-listed species (linnet Carduelis cannabina, yellowhammer Emberiza citrinella, corn bunting E. calandra) were more likely to be recorded on plots than in the crop. A fifth (lapwing Vanellus vanellus) was almost exclusively recorded from plots, and was more likely to be recorded on plots categorised as in good condition for stone curlews. These results demonstrate that fallow plots that have been put in place for the recovery of stone curlews have considerable value for a range of other farmland biodiversity, although management for stone curlews may be detrimental to some taxa, such as carabid beetles, that are sensitive to the relatively frequent spring tillage that these plots receive.  相似文献   
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