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71.
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A storage disease characterised by widespread vacuolation of cells throughout the body was diagnosed in a newborn calf of the Salers breed. Extraction and analyses of water soluble material showed that the storage material was oligosaccharide in nature and was probably derived from the core region of the heterosaccharide moiety of glycoproteins. Glycosidase analyses showed that the disease was due to a deficiency of acidic beta-mannosidase.  相似文献   
74.
GENERALISED GLYCOGENOSIS IN BRAHMAN CATTLE   总被引:4,自引:0,他引:4  
Generalised glycogenosis was diagnosed in Brahman cattle on 4 Queensland properties on the basis of clinical observations and pathological and biochemical findings. The disease presented as a problem of ill-thrift and poor growth rate in calves which eventually showed nervous signs. Histologically there was vacuolation in the cells of the central nervous system, heart and muscular tissues. Biochemical assay of liver and blood mononuclear cells demonstrated a deficiency of alpha-glucosidase. Parents of affected calves had approximately half the alpha-glucosidase activity of that found in normal cattle.  相似文献   
75.
Thirty-four newborn polled Hereford and polled Hereford cross calves affected with a condition previously described as neuraxial oedema and six normal calves were examined. None of the affected calves were seen to stand after birth and when first examined the calves were in lateral recumbency, with extension and crossing of the hindlimbs. All the affected calves were bright and alert, could lift their heads and apparently could see and hear. When the calves were encouraged to stand spontaneous and stimulus-responsive myoclonic extensor spasms, with whole body rigidity, were consistently observed. Thirty-two of the affected calves had macroscopic lesions in the coxae. No significant pathological or biochemical lesions were observed in the central nervous system of any of the calves. The water content of the cerebellum did not differ between normal and affected calves. As oedema of the central nervous system is not a feature of this condition it is more appropriate to describe it as inherited congenital myoclonus.  相似文献   
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In humans, regulatory T (T reg) cells are known to play a critical role in both the regulation of immune homoeostasis and the progression of cancer. However, there is little information about the identification, characterization and the function of T reg cells in canine tumours. We identified T reg cells in 28 canine seminoma samples using a Forkhead box P3 (Foxp3) antibody and investigated the relationship between T reg cell infiltration and histopathological features of classical and spermatocytic seminomas (SE and SS, respectively). The Foxp3 protein showed nuclear immunostaining in infiltrating lymphocytes, and Foxp3+ cells were diffused or focally distributed in seminoma tissues. Foxp3+ cells were frequently present in the SS histotype, in seminomas that showed no evidence of tumour cell invasion into the vessels and in seminomas showing a diffuse growth pattern with three cell types. Neither the SE/SS histotype nor the histopathological features of the tumour correlated with Foxp3+ cell counts. These results indicate that Foxp3+ T reg cells may be associated with a less malignant histological phenotype or may not play a critical role in the immune response of canine seminomas. Moreover, Foxp3+ T reg cells may be associated with SS seminoma, but further studies, involving a larger number of samples, are required to better understand whether these cells play a critical role in the immune response in canine seminomas. This is the first report to demonstrate the characteristics of T reg cell infiltration in canine seminoma.  相似文献   
78.
Diet interactions between native and non‐native fishes may influence the establishment of native species within their historical range (i.e., reintroduction). Therefore, we illustrated the food web structure of and followed the transition of the federally endangered humpback chub Gila cypha into a novel food web following translocation and determined the potential for a non‐native species, rainbow trout Oncorhynchus mykiss, to influence translocation success. Humpback chub and rainbow trout used resources high in the food web and assimilated similar proportions of native fishes, suggesting non‐native rainbow trout may occupy an ecological role similar to humpback chub. Subsequently, humpback chub may be well suited to colonise tributaries because of their ability to consume resources high in the food web. Additionally, diet partitioning may occur between all members of the fish community as indicated by separation in trophic niche space and little trophic overlap; although all species, particularly bluehead sucker Catostomus discobolus, used a broad range of food resources. Rainbow trout stomach content analysis corroborated stable isotope analysis and suggested rainbow trout diet consisted of aquatic and terrestrial macroinvertebrates, while larger rainbow trout (>120 mm total length) consumed a greater proportion of fish (incidence of piscivory = 5.3%). Trophic interactions may reveal an underutilized niche space or biotic resistance to the establishment of translocated native fishes. Continued translocation of humpback chub into tributaries appears to be one option for conservation. However, successful establishment of humpback chub may depend on continued removal of non‐native trout, increasing availability of diet sources at higher trophic levels.  相似文献   
79.
Several studies have previously been conducted regarding cell cycle synchronization in mammalian somatic cells. However, limited work has been performed on the control of cell cycle stages in the somatic cells of fish. The aim of this study was to determine the cell cycle arresting effects of several dimethyl sulfoxide (DMSO) concentrations for different times on different cell cycle stages of goldfish caudal fin‐derived fibroblasts. Results demonstrated that the cycling cells or control group (68.29%) yields significantly higher (p < 0.05) arrest in G0/G1 phase compared with the group treated for 24 h with different concentrations (0.5%, 1.0% or 1.5%) of DMSO (64.88%, 65.70%, 64.22% respectively). The cell cycle synchronization in the treatment of cells with 1.0% DMSO at 48 h (81.14%) was significantly higher than that in the groups treated for 24 h (76.82%) and the control group (77.90%). Observations showed that treatment of DMSO resulted in an increase in the proportion of cells at G0/G1 phase for 48 h of culture. However, high levels of apoptotic cells can be detected after 48 h of culture treated with 1% concentration of DMSO.  相似文献   
80.
Breeding experiments were conducted in 1984, 1985 and 1986, using Angus and Galloway bulls and cows that were obligatory heterozygotes for alpha-mannosidosis. Sixty-nine calves were born in the herd of which 16 were diagnosed as cases of alpha-mannosidosis. The clinical and pathological findings in eight Angus cross Angus, four Galloway cross Angus, and four Galloway cross Galloway calves affected with alpha-mannosidosis are reported. Thirteen calves displayed neurological signs in the early neonatal period. Three Galloway cross Galloway calves were stillborn. The severity of disease caused death or necessitated euthanasia within the first week of life of 10 affected calves. Three Angus cross Angus calves survived 40, 80 and 210 days. These findings illustrate significant variation in the phenotypic expression of alpha-mannosidosis both within and between the breeds.  相似文献   
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