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41.
An atypical case of lymphosarcoma (sporadic bovine leukosis) in a heifer.   总被引:2,自引:0,他引:2  
An 18-month-old Friesian heifer had several unusual, raised, black, cutaneous plaques, some of which were up to 20 cm in diameter, on its head and neck, limbs, thorax and perineum. There was also generalised lymphadenopathy. A clinical diagnosis of lymphosarcoma (sporadic bovine leukosis) was derived from a fine needle aspiration of a skin lesion. Post mortem and histological examinations confirmed a multicentric lymphosarcoma with widespread infiltration into many of the tissues recognised as predilection sites for this type of tumour. However, in the authors' experience, the presence of tumour masses in the trachea and the right mainstem bronchus was atypical.  相似文献   
42.
A five-year-old German shepherd dog was presented with a severe scrotal dermatitis of four weeks duration which had failed to respond to antibiotic and corticosteroid therapy. Dermato-histopathology indicated that the lesion was a necrolytic process suggestive of the hepatocuta-neous syndrome. Clinical biochemistry investigations indicated the presence of acute hepatocellular damage and cholestasis. The animal was fed a biscuit meal which was damp and mouldy. Penicillium vindication was grown from this feedstuff and three mycotoxins, citrinin, ochratoxin A and sterigmatocystin, were found; substances which have been associated with renal and hepatic lesions in dogs and laboratory animals. Symptomatic therapy and nutritional management, led to rapid clinical improvement. Subsequent plasma biochemistry confirmed that hepatic enzyme activities were returning to normal levels.  相似文献   
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Questionnaires were posted to 800 randomly selected registered Victorian dairy farmers in 1996. Five hundred and thirty-four responses were received and analysed. Johne's disease (JD) had been diagnosed on the farm of 13.2% of respondents in the last 5 years. JD was rated second only to neonatal diarrhoea in importance as a disease of calves, even though other diseases occurred more frequently. However, there was a low level of compliance with JD control recommendations by the respondents. There was no significant difference in the number of JD control recommendations adopted by farmers between the three major Victorian regions. There was a significant difference in compliance between farms having had a diagnosed case of JD and those that had not. Although there is awareness among dairy farmers of the importance of JD, there appears to be a poor implementation of measures by farmers to prevent the spread of the disease. Current JD control recommendations and the method of information transfer to Victorian dairy farms should be reassessed to ensure that dairy heifers are reared with minimal risk of transmission of JD.  相似文献   
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We have used a porcine model of spontaneous differential fetal growth to investigate the effects of fetal size on muscle development. We hypothesized that altered muscle development may occur in small fetuses as a consequence of modified expression of selected genes of the insulin-like growth factor system. We examined the development of the Longissimus muscle (m. Longissimus) in small fetuses and their average sized littermates. We collected small for gestational age fetuses and their average sized sibling on days 45, 65 and 100 of gestation (term is 113-116 days). Small fetuses had significantly lower body weight at all three stages of gestation (p<0.05) and significantly reduced secondary to primary muscle fibre ratio in m. Longissimus on day 100 (p<0.05) compared to their littermates. On day 65, the expression of insulin-like growth factor receptor 1 and insulin-like growth factor binding protein 3 were significantly higher (p<0.05) in m. Longissimus of the small fetuses compared with their average sized littermates. On day 100, the expression of insulin-like growth factor receptor 1 remained significantly higher (p=0.001), in addition to significantly higher levels of insulin-like growth factor receptor 2 and insulin-like growth factor binding protein 5 in the small fetuses (p<0.05). No difference in levels of myogenin was observed between the small and average sized littermates. In conclusion, we demonstrate that reduced fetal muscle development is associated with an increased expression of several genes of the insulin-like growth factor system in small fetuses in mid to late gestation.  相似文献   
47.
Ninety-two doubled haploid (DH) lines, generated from a cross between Franklin and TX9425 (a Chinese Landrace), were grown in three environments to identify quantitative trait loci (QTLs) controlling agronomic traits including heading date, plant height and spike characteristics. The DH lines showed a wide range of variations for all the agronomic traits tested. Most of the traits were controlled by one or two major QTLs which explained 9.5–80.9% of the phenotypic variation. Two dwarfing genes were identified from the cross. One of the dwarfing genes was from Franklin, which is the same as the previously reported denso gene. The other dwarfing gene was from the Chinese landrace variety. Both dwarfing genes were temperature and/or day length sensitive. The dwarfing gene from Franklin was more effective in early sowing trials (shorter day length and lower temperature) while the gene from TX9425 was more effective in later sown trials. The dwarfing gene from TX9425 was located at a similar position to the uzu gene. However, it differed from this gene being temperature sensitive with very close links to short spikes, awns and high grain density which is more like a brh gene. To effectively use this gene in a breeding program, it is necessary to break the linkage between the dwarfing gene and the unfavourable spike traits.  相似文献   
48.
Based on the boron isotopic composition of coral from the southwestern Pacific, Pelejero et al. (Reports, 30 September 2005, p. 2204) suggested that natural variations in pH can modulate the impact of ocean acidification on coral reef ecosystems. We show that this claim cannot be reconciled with other marine carbon chemistry constraints and highlight problems with the authors' interpretation of the paleontologic data.  相似文献   
49.
OBJECTIVES: The aim of this study was to identify clinical features that could be used to identify individual dogs within the Guide Dogs for the Blind Association canine population at risk of being diagnosed as atopic in the future before they had fully developed the condition. METHODS: Clinical histories of atopic and non-atopic dogs from the Guide Dogs for the Blind Association population were analysed and statistically significant differences identified between the two groups. RESULTS: Atopic dogs were consistently affected by skin disease at a younger age than non-atopic dogs and that there was a significant difference in event curves between atopic and non-atopic dogs at 10 months of age. From a predictive point of view, dogs that suffered from four or more episodes of atopic-type skin disease by the age of 15 months were at an increased risk of developing atopic dermatitis. CLINICAL SIGNIFICANCE: It is suggested that the clinical history of all dogs from the Guide Dogs for the Blind Association about to undergo training should be examined for these factors to assess whether or not they should undergo training.  相似文献   
50.
Feline myeloma-related disorders (MRD) are rare neoplasms of plasma cells. The multistep transformation model of myeloma in humans is based on the premise that plasma cells undergo neoplastic transformation primarily within the intramedullary compartment and that over time they become poorly differentiated and metastasize to extramedullary locations. Historically, diagnostic criteria used for human multiple myeloma have been applied to the cat, with the assumption that feline MRD commonly arises in the intramedullary compartment. Our objectives were to describe the features of feline MRD confirmed by cytology, histopathology, histochemistry, and immunohistochemistry and to categorize these tumors. A priori hypotheses were 1) tumor category predicts survival and 2) cats with well-differentiated tumors commonly have extramedullary involvement in contrast to human myeloma patients. This multicenter, retrospective study identified 26 MRD cases. There was good agreement between histopathologic and cytologic tumor categorization. Histochemistry and immunohistochemistry were shown to be valuable adjunct tests in the diagnosis of MRD. Cats with well-differentiated tumors had increased median survival relative to those with poorly differentiated tumors (254 versus 14 days). We have reported that marked extramedullary involvement at initial clinical presentation is significantly more common in the cat than in human MRD patients. In this study, we demonstrate that cats with well-differentiated tumors more commonly have extramedullary involvement than human myeloma patients with well-differentiated tumors (90% versus 20%, P < 0.0002). These results contrast strongly with the human myeloma model of primary intramedullary neoplastic transformation and suggest that primary extramedullary neoplastic transformation may be more common in feline MRD.  相似文献   
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