首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   35篇
  免费   6篇
林业   3篇
农学   2篇
  5篇
综合类   2篇
农作物   2篇
畜牧兽医   24篇
园艺   1篇
植物保护   2篇
  2022年   1篇
  2019年   4篇
  2018年   3篇
  2017年   3篇
  2016年   1篇
  2014年   2篇
  2013年   1篇
  2012年   4篇
  2011年   3篇
  2010年   3篇
  2009年   1篇
  2008年   3篇
  2007年   1篇
  2006年   2篇
  2002年   4篇
  2001年   1篇
  2000年   1篇
  1997年   1篇
  1974年   1篇
  1973年   1篇
排序方式: 共有41条查询结果,搜索用时 31 毫秒
31.
A cat with multiple subcutaneous nodules suggesting a soft tissue sarcoma by physical and computed tomographic examination was diagnosed as being affected by subcutaneous filariosis based on cytologic and ultrasonographic assessments. Nodules were surgically removed and extracted nematodes were identified by PCR as Dirofilaria repens. Furthermore, DNA of Dipetalonema dracunculoides (syn. Acantocheilonema dracunculoides) was detected by PCR, with no evidence of circulating microfilariae. To the best of the authors' knowledge, this represents the first report describing adults of D repens in multiple subcutaneous nodules in a cat. Cytopathologic examination allowed characterization of the parasitic nature of the nodules. Veterinary practitioners should be aware of the possible nodular presentation of D repens in cats and should include D repens in the differential diagnosis of subcutaneous neoformations in the cat.  相似文献   
32.
33.
Finding new effective compounds of natural origin for composing anti-tumor vaccines is one of the main goals of antitumor research. Promising anti-cancer agents are the gastropodan hemocyanins–multimeric copper-containing glycoproteins used so far for therapy of different tumors. The properties of hemocyanins isolated from the marine snail Rapana thomasiana (RtH) and the terrestrial snail Helix aspersa (HaH) upon their use as carrier-proteins in conjugated vaccines, containing ganglioside mimotope GD3P4 peptide, were studied in the developed murine melanoma model. Murine melanoma cell line B16F10 was used for solid tumor establishment in C57BL/6 mice using various schemes of therapy. Protein engineering, flow cytometry, and cytotoxicity assays were also performed. The administration of the protein-engineered vaccines RtH-GD3P4 or HaH-GD3P4 under the three different regimens of therapy in the B16F10 murine melanoma model suppressed tumor growth, decreased tumor incidence, and prolonged the survival of treated animals. The immunization of experimental mice induced an infiltration of immunocompetent cells into the tumors and generated cytotoxic tumor-specific T cells in the spleen. The treatment also generates significantly higher levels of tumor-infiltrated M1 macrophages, compared to untreated tumor-bearing control mice. This study demonstrated a promising approach for cancer therapy having potential applications for cancer vaccine research.  相似文献   
34.
The objective of this study was to determine genotype × environment interactions (GEI) obtained in wheat production in southeast Europe for protein content, sedimentation value, and loaf volume. Twenty wheat genotypes divided in two groups with different combinations of high molecular weight glutenin subunits (HMW-GS) were analyzed in 15 environments (E). In a combined analysis of variance, effects of genotype, environment, and their interaction (GEI) were highly significant for almost all the analyzed traits. All the three traits were influenced more by location than by year, with protein content and sedimentation value being more responsive to changes in environmental conditions than loaf volume. The genotypes with high protein content had the regression coefficient value (b) close to 1, indicating that they did not react to extreme environmental conditions as was the case with genotypes with high sedimentation and loaf volume values. There were no significant differences in average values for the analyzed traits and adaptability parameters between the two groups of genotypes. It means that, concerning wheat quality improvement, genotypes with different HMW-GSs on the Glu-1D locus could be recommended for growing in southeast Europe. It is necessary to take into account the differences in adaptability of protein content to either positive or negative environmental changes that were observed between the groups.  相似文献   
35.
Mycobacterium avium subsp. avium (MAA) and Mycobacterium avium subsp. hominissuis (MAH) are the most common mycobacterial species isolated from granulomatous lesions in swine in countries with controlled bovine tuberculosis. This study is focused on the immunological aspect of MAA and MAH infection in pigs. We detected induction of humoral and cell-mediated immunity in experimentally infected pigs. Specific antibodies were analyzed in serum by ELISA and the IFN-γ release assay was used for evaluation of cell-mediated immunity. While MAA induced a significant increase of both types of immune responses, MAH-infected pigs had an unvarying level of specific antibodies and showed low cell-mediated immunity with high individual variability. The subsequent in vitro experiment confirmed the lower immunogenicity of the MAH strain in comparison to MAA. MAH-infected porcine monocyte-derived macrophages showed a weaker induction of pro-inflammatory mediators in comparison to MAA, which included mRNA for IL-1β, TNF-α, IL-23p19, IL-18 and chemokines CCL-3, CCL-5, CXCL-8 and CXCL-10. Additionally, qualitative proteomic analysis revealed 28 proteins exclusively in MAA and 7 proteins unique to MAH. In conclusion, closely related M. avium subspecies MAA and MAH showed different capacities to stimulate the porcine immune system. From a diagnostic point of view, the IFN-γ release assay showed higher sensitivity than the detection of specific antibodies by ELISA and seems to be an effective tool for discrimination of MAA-infected pigs. In the case of MAH infection, the IFN-γ release assay could fail because of the low immunogenic capacity of the MAH strain.  相似文献   
36.
Adequate storage compounds are a prerequisite for successful development during the later stages of somatic embryogenesis; however, the critical amount of reserves below which somatic embryos fail to mature and germinate has not been determined. We analyzed storage lipids during Norway spruce (Picea abies (L.) Karst.) somatic embryogenesis. As maturation progressed, lipids, which were stored as lipid bodies in the cytoplasm, were localized first in suspensor cells of the early embryos, and later in the embryonic root pole, superficial layers of the hypocotyl and in cotyledons. The concentration of total lipids exhibited marked variation, with values peaking during cotyledon development and then decreasing during maturation. Linoleic (18:2), oleic (18:1), palmitic (16:0) and 5,9-octadecenic (5,9-18:2) acids were the most abundant fatty acids in embryos. As embryos developed, linoleic acid concentration increased slightly, whereas oleic acid concentration decreased. Oleic acid was the most prominent component of the fatty acid spectrum in isolated dormant zygotic embryos and megagametophytes. Addition of 5% polyethylene glycol to the medium during somatic embryo maturation caused a shift in the fatty acid spectrum toward that of zygotic embryos. During maturation, changes in the exogenous carbohydrate supply had no significant effect on total lipid concentration in mature embryos. A marked decrease in lipid concentration was detected during desiccation, indicating the importance of adequate lipid reserves during this developmental stage. The lipid content of zygotic embryos differed considerably with harvest year and location, suggesting that zygotic embryo data cannot be an indicator of somatic embryo quality.  相似文献   
37.
A study was made of the effect of hot water dips (HWD) at temperatures of 42, 44, 46 and 48 °C (HWD 42 °C, HWD 44 °C, HWD 46 °C and HWD 48 °C, respectively) for 3 min on development of superficial scald and the concentration of α-farnesene and conjugated trienols (CT), CT259, CT269, CT281, as well as OD200 on Granny Smith apple fruits harvested on three dates and stored 125 days in air at 2 °C. HWD 48 °C efficiently decreased surface scald in the second and third harvest. α-Farnesene and CT were measured spectrophotometrically and by HPLC. No clear relationship of OD200 and scald development was observed. Correlation of scald index and OD200 at the end of storage was negative for the second harvest date. There was no significant correlation between the scald index and CT259. Scald index was positively correlated with CT269 after 80 days for the second and third harvest and at the end of storage for the second harvest. CT281 was spectrophotometrically detectable only at the end of the storage, for the third harvest date, in control, HWD 42 °C, and HWD 44 °C. HWD 42 °C had significantly higher CT281 compared to HWD 44 °C and control. HPLC analysis of control samples revealed presence of CT281 in all three harvest dates, and presence of at least two components, as was the case of CT259 and CT269. The ratio of these two components was different for all three CT species. Fruit maturity was an important factor determining the response of fruit to heat and occurrence of superficial scald. The results indicate that a successful treatment using HWD to control superficial scald may be obtained after further research and that there are still some questions on the role of different CT's in scald biochemistry that should be addressed in future research.  相似文献   
38.
A 7‐year‐old Jack Russell Terrier with a history of minor trauma was presented for lameness of the left forelimb. Radiography and computed tomography demonstrated a localized radioulnar osteolytic lesion with cortical bone loss and enthesiophytes. Based on results of diagnostic imaging and histopathological examination, the final diagnosis was radioulnar ischemic necrosis (RUIN), complicated by pathologic fracture. A rare disorder of unknown etiology, RUIN may be secondary to tearing of the interosseous ligament and potential ischemia. It should be differentiated from neoplastic or fungal disease. To the authors´ knowledge, this is the first canine case report describing RUIN.  相似文献   
39.

Background

Exotic reptiles have become increasingly common domestic pets worldwide and are well known to be carriers of different parasites including some with zoonotic potential. The need of accurate diagnosis of gastrointestinal endoparasite infections in domestic reptiles is therefore essential, not only for the well-being of captive reptiles but also for the owners. Here, two different approaches for the detection of parasite stages in reptile faeces were compared: a combination of native and iodine stained direct smears together with a flotation technique (CNF) versus the standard SAF-method.

Results

A total of 59 different reptile faeces (20 lizards, 22 snakes, 17 tortoises) were coprologically analyzed by the two methods for the presence of endoparasites. Analyzed reptile faecal samples contained a broad spectrum of parasites (total occurence 93.2%, n = 55) including different species of nematodes (55.9%, n = 33), trematodes (15.3%, n = 9), pentastomids (3.4%, n = 2) and protozoans (47.5%, n = 28). Associations between the performances of both methods to detect selected single parasite stages or groups of such were evaluated by Fisher''s exact test and marginal homogeneity was tested by the McNemar test. In 88.1% of all examined samples (n = 52, 95% confidence interval [CI] = 77.1 - 95.1%) the two diagnostic methods rendered differing results, and the McNemar test for paired observations showed highly significant differences of the detection frequency (P < 0.0001).

Conclusion

The combination of direct smears/flotation proved superior in the detection of flagellates trophozoites, coccidian oocysts and nematode eggs, especially those of oxyurids. SAF-technique was superior in detecting larval stages and trematode eggs, but this advantage failed to be statistically significant (P = 0.13). Therefore, CNF is the recommended method for routine faecal examination of captive reptiles while the SAF-technique is advisable as additional measure particularly for wild caught animals and individuals which are to be introduced into captive collections.  相似文献   
40.
Research on oil residuals in lowland forest soil was carried out in 6 sample plots in the lowland forest ecosystem located in an oil field. Four plots were differently affected in terms of discharged oil and the time lapsed after the accident, as well as in terms of micro-relief terrain features. One plot was established in a reclaimed mud ditch site, while the control plot was set up in a micro-relief elevation outside the influence of oil pollution. Total petroleum hydrocarbon (TPH) concentrations were measured at three soil depths at the beginning and the end of the vegetation period. The analysis of the results revealed significant differences in petroleum hydrocarbon concentrations among the sites. Increased TPH concentrations were recorded in several plots, while the values measured in some other plots indicated very low quantities of residual TPH in the soil. The highest average TPH concentrations (200–400 mg kg1) were recorded in the mud ditch site. In one of the plots exposed to oil pollution after an oil pipe rupture, there was the constant presence of increased TPH concentration in the surface soil part (≥200 mg kg1 on average). The sporadic presence of increased TPH concentrations in micro-depressions that cannot be attributed to a local accident indicates seasonal soil pollution with petroleum carbohydrates from floodwater. The soil in the sample plots is not contaminated with soluble salts or heavy metals. Low values of TPH concentrations in the soil water eluate indicate that the soil does not represent a source of hydrospheric pollution with petrol hydrocarbons.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号