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11.
One hundred fifty Se-deficient, pregnant, crossbred beef cows were assigned to 1 of 4 treatment groups: group A, Se-deficient control; group B, 1 Se bolus at 0 and 119 days; group C, 1 Se bolus at 0 days; and group D, 2 Se pellets at 0 days. The Se bolus is an osmotic pump designed to release 3 mg of Se/d into the reticulorumen. The Se pellets weight approximately 30 g and contain 10% elemental Se, which is liberated in the reticulorumen. The Se bolus is designed to provide Se supplementation for 120 days and the Se pellets provide supplementation for up to 18 months. Cattle were maintained on Se-deficient pasture or forages prepared from these pastures for the duration of the experiment. Blood samples were collected from cows prior to treatment (time 0) and at 28, 52, 119, and 220 days thereafter and analyzed for blood Se (BSe) concentration. Body weights were recorded at each sampling time. Blood Se concentration of cows from all supplemented groups were significantly (P less than 0.01) higher than control values at all sample dates after treatments began. By the end of the 220-day study, treatment group-B cattle had significantly (P less than 0.01) higher BSe concentrations than any other group. Body weights of treatment groups fluctuated throughout the study, but did not differ (P greater than 0.05) between groups. One cow and 6 calves born to cows during the experimental period died. Necropsy of 5 calves provided no evidence linking these deaths to treatments.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
12.
Summary Important papers on taxonomy and evolution of cultivated plants published in 1985 and 1986 were compiled and briefly discussed.
Taxonomie und Evolution der Kulturpflanzen: Literaturübersicht 1985/1986
Zusammenfassung Wichtige Arbeiten über Taxonomie und Evolution der Kulturpflanzen aus den Jahren 1985 und 1986 wurden zusammengestellt und kurz kommentiert.

¶rt; : 1985–1986
¶rt; , 1985 1986 . .
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Growing resistant potato cultivars is of little help in avoiding damage by spraing, because of regionally differing strains of tobacco rattle virus and of special requirements of the processing industry. On soil, fumigated in 1971 during autumn with a solution of dichloropropene-dichloropropane (660 g/l) at 250 l/ha, the vectorsTrichodorus spp., were effectively controlled and the tuber disorder did not appear in the next year's potato crop. But potatoes from the treated plots had an unacceptable off-flavour. In the second crop after treatment, control was still good and there was no difference in flavour between potatoes from treated and untreated plots. Disease incidence was significantly lower after spring barley than after sugarbeet, maize, or potatoes.  相似文献   
17.
Two 2-year-old Salers cattle from different herds raised on pasture were evaluated for retarded growth and diarrhea. Increase of liver enzyme activities and prolonged sulfobromophothalein (BSP) half life (T1/2) indicated liver disease with impaired liver function. Histopathologic examination of liver biopsies revealed a micronodular cirrhosis with marked deposition of hemosiderin in hepatocytes, Kupffer cells, and arterioles. Transferrin saturation (TS) and liver iron content were markedly increased, consistent with a diagnosis of hemochromatosis. Both animals were euthanatized due to deterioration in their condition. Necropsy findings included hepatomegaly and hemosiderin accumulation in the liver, lymph nodes, pancreas, spleen, thyroid, kidney, brain and other glandular tissue. Continued surveillance of the second herd (serum iron, total iron binding capacity [TIBC], unsaturated iron binding capacity [UIBC], and TS), identified a heifer as a hemochromatosis suspect in a subsequent generation. Liver biopsies from that animal revealed the same histopathologic changes as the previous 2 animals, and similar increases in liver iron content (8,700 ppm, normal range 45 to 300 ppm). The 3 affected cattle were all products of line breeding programs and shared a common ancestor. The absence of dietary iron loading in conjunction with the histopathologic and metabolic findings were consistent with a diagnosis of primary hemochromatosis. The reported disease is similar to idiopathic hemochromatosis in human beings in which there is a hereditary defect in iron metabolism.  相似文献   
18.
The investigations on the cause of the “Lent disease” of mother plants as well as cuttings ofPelargonium zonale have indicated, that these troubles are due to faulty cultural methodes combined with an infection byCorynebacterium fascians and “weakness parasites”. The bacteria cause the axillary buds to develop leafy galls on the stem under the soil level and small tumorous growths on the cortex of the stem above, the socalled corky spots. The infected plants may not wither, but galls and spots are more easily infected by pathogens than healthy plants. FrequentlyBotrytis cinerea infects these tissues and causes the black base rot. Spraying the mother plants with streptomycin (Fytostrep 60: 2.5 ml/l) and thiram (0.2%) decreased the base rot, but markedly inhibited the rooting of the cuttings. Moreover, the inocula of bothC. fascians andB. cinerea are present in such a large quantity, that full control is impossible. Reduction of losses may be achieved by improvement of cultural methods and soil disinfection.  相似文献   
19.
An alfalfa experiment was conducted in the Wellton-Mohawk Irrigation and Drainage District of Southwest Arizona to determine the potential for minimizing the salt load in irrigation return flow by decreased leaching. Three leaching treatments of 5, 10, and 20%, replicated five times, were imposed on a 2-ha field. The crop was irrigated with Colorado River water (electrical conductivity of 1.3 dS m?1) through a lateral-move, spray-type irrigation system. Results were compared with those of an adjacent area irrigated with level basin flooding.The average annual evapotranspiration during the 4-year study was 1930 mm. Several indirect measures of the leaching fractions attained gave average values of 6.4, 9.3, and 13.1% for the three leaching treatments. Mean annual yields were 21.5 and 22.9 Mg ha?1 for 1977 and 1978 in the experimental plots, with no significant differences among leaching treatments, and 25.7 and 20.8 Mg ha?1 in the adjacent flooded check. The results suggest that full yields could be attained with as little as 5% leaching.Estimates based on average on-farm irrigation efficiency for alfalfa in the District in 1979, indicate that 5% leaching, if attainable, would reduce the salt load in the irrigation return flow by 39 000 Mg year?1 on 8 000 ha of alfalfa.  相似文献   
20.
The posttranslational modification sumoylation can have multiple effects on its substrate proteins. We studied a patient with isolated cleft lip and palate and a balanced chromosomal translocation that disrupts the SUMO1 (small ubiquitin-related modifier) gene, resulting in haploinsufficiency. In mouse, we found that Sumo1 is expressed in the developing lip and palate and that a Sumo1 hypomorphic allele manifests an incompletely penetrant orofacial clefting phenotype. Products of several genes implicated in clefting are sumoylated, and the Sumo1 hypomorphic allele interacts genetically with a loss-of-function allele for one of these loci. Thus, sumoylation defines a network of genes important for palatogenesis.  相似文献   
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