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Inoculation of cucumber (Cucumis sativus L. cv. Laura) cotyledons with tobacco necrosis virus (TNV) causes both qualitative and quantitative changes in the total and fractionated protein extracts as well as in amylolytic activity. Using a specific test it was demonstrated that the virus infection strongly enhances a major band (Rf 0.0645) of amylolytic activity, predominantly located in apoplast space. The accumulation of this extracellular amylolytic activity is regulated by a time-dependent manner and is correlated with the development of necrotic lesions. The amylolytic activity may be related to degradation of starch shown to be accumulated in the immediate vicinity of necrotic lesions associated with the hypersensitive response (HR). The possible biological function of the identified amylolytic activity in the term of ,,pathosmosis" is also discussed.  相似文献   
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996.
Physicians and other health personnel dealing with the consequences of child abuse ought to have abroad understanding of the magnitude of this serious medical and social phenomenon. The three main patterns of child mistreatment as observed at a pediatric hospital are reviewed, with emphasis on its medical and juridical aspects. Various pathologic entities are to be taken into account for differential diagnoses when child abuse is suspected. Risk factors regarding the victims, the abusers and the psychosocial environment are noted.  相似文献   
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Oborilová E  Rybnikár A 《Mycoses》2005,48(3):187-191
Microconidia suspension of Trichophyton verrucosum virulent culture isolated originally from the mycotic lesions of cattle was inoculated epicutaneously to calves in various doses. Four application methods were selected, namely, onto the sheared and gently scarified skin, onto the sheared and non-scarified skin, onto the non-sheared and gently scarified skin, and onto the non-sheared and non-scarified skin. The inoculated area was 10 x 10 cm for all cases mentioned. When the application was performed onto the sheared and scarified skin, at least 18,000 microconidia of T. verrucosum per one animal had to be used to induce the mycotic disease in 100% of animals. This value was 10 times higher when the application was performed onto the non-sheared and scarified skin, 100 times higher in the case of the sheared and non-scarified skin and 1,000 times higher in the case of the non-sheared and non-scarified skin. The minimum infectious dose still capable of inducing dermatophytosis was 180 microconidia per 100 cm(2) of the scarified skin, 18,000 microconidia per 100 cm(2) of the sheared and non-scarified skin, and 180,000 microconidia per 100 cm(2) of the non-sheared and non-scarified skin.  相似文献   
999.
Sodium butyrate or glucose deprivation induce a more differentiated phenotype in many cancer cells. The aim of this study was to determine whether the induction effect of butyrate and/or glucose deprivation is dependent, in some way, on the differentiation state of individual cell lines. Sodium butyrate enhanced alkaline phosphatase activity and induced formation of an ultrastructurally more differentiated phenotype in both HT29 and HT115 cell lines. Interestingly, the more invasive HT115 cells responded more strongly to butyrate treatment. On the other hand, the differentiation effect of glucose deprivation was much less prominent in the HT115 cell line in comparison with HT29 cells. Our data confirm the influence of the malignant potential of the cells on their response to treatment with differentiation and apoptosis-inducing agents. Butyrate treatment also enhanced the adhesiveness of HT115 cells. Since E-cadherin was not found in these cells, while the level of CEACAM1 was increased, it is obvious that the CEACAM1 molecules are involved in HT115 cell-cell adhesion.  相似文献   
1000.
Hodgkin's lymphoma and tuberculosis coexistence in cervical lymph nodes   总被引:1,自引:0,他引:1  
We describe the case of a 47-year-old man admitted to the Department of Hematology because of fever, enlarged cervical and supraclavicular lymph nodes, hepatosplenomegaly and non-specific lung infiltrations. The histopathological examination of the cervical lymph node revealed Hodgkin's lymphoma (HL) NS type I. Clinical evaluation revealed stage IVB according to Ann Arbor classification and the presence of 5 unfavorable prognostic factors according to the International Prognostic Index. Despite BEACOPP chemotherapy (bleomycin, etoposide, doxorubicin, cyclophosphamide, vincristine, procarbazine, and prednisone), the enlarged lymph nodes, lung infiltrations and fever persisted. Microbiological and serological tests did not lead to the identification of any viral or bacterial pathogens. Bronchoscopy showed chronic inflammation and post-tuberculosis (TB) scars in bronchi without acid-fast bacilli in bronchoalveolar lavage (BAL) in culture and polymerase chain reaction (PCR) tests. However, the biopsy of the supraclavicular lymph node revealed multiple, caseating and necrotizing granulomatous lesions with scattered Reed-Sternberg (R-S) cells. The auramin staining presented acid-fast bacilli and allowed the diagnosis of productive and caseating TB coexisting with HL. The 4 tuberculostatics regimen and ABVD chemotherapy (adriamycin, bleomycin, vincristine, dacarbazine) resulted in a complete clinical response after 3 months of treatment. In conclusion, the association between HL and TB must be considered, especially in countries where the latter is endemic. The diagnosis may be difficult due to similarities in the clinical course, laboratory tests and imaging procedures.  相似文献   
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