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1.
Dietary polyamines promote the growth of azoxymethane-induced aberrant crypt foci in rat colon 总被引:1,自引:1,他引:1
We have examined whether dietary polyamines influence the formation and
initial growth of azoxymethane (AOM)-induced aberrant crypt foci (ACF) in
rat colon. Effects of a combination of dietary polyamines at three dose
levels (putrescine: 50, 280, 740 nmol/g; spermidine: 10, 261, 763 nmol/g;
spermine: 1, 31, 91 nmol/g) in the polyamine-poor AIN-76A diet were studied
in animals in two different experimental situations: animals treated with
AOM alone and animals treated with AOM + difluoromethylornithine (DFMO), a
specific inhibitor of endogenous polyamine synthesis. In both experimental
situations, dietary polyamines enhanced the growth of ACF, expressed as the
number of large ACF (foci with three or more aberrant crypts, ACF > or =
3), whereas the formation of ACF, expressed as the number of ACF, was
apparently not altered. In animals treated with AOM alone, maximal growth
enhancing effect on ACF was nearly obtained with the median level of
dietary polyamine. In rats fed a low polyamine diet, basic AIN-76A, DFMO
reduced the growth of AOM-induced ACF by 83%. This inhibitory effect of
DFMO was counteracted by dietary polyamines in a dose- dependent manner,
and it was abolished at the highest level of polyamines. In conclusion, it
was demonstrated that dietary polyamines are able to enhance the growth of
AOM-induced ACF. Further, dietary polyamines reversed the DFMO-caused
inhibition of ACF growth, probably by compensating for the DFMO-reduced
endogenous polyamine synthesis.
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2.
A case of malignant eccrine cylindroma of the skin studied immunohistochemically is reported. 相似文献
3.
V A Iavelov O V Za?rat'iants N L Chazova A M Bershchanskaia O V Paklina 《Arkhiv patologii》1999,61(2):55-60
Benign epithelial tumor of the skin--eccrine spiradenoma--is characterized in detail clinically and morphologically. 相似文献
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The authors describe a case of hepatoid adenocarcinoma of the lung with multiple metastases to the small bowel. An immunohistochemical study has been conducted. 相似文献
7.
I. VANČOVÁ V. HAJNICKÁ M. SLOVÁK P. KOCÁKOVÁ G. C. PAESEN P. A. NUTTALL 《Parasite immunology》2010,32(6):460-463
Ticks exploit many evasion mechanisms to circumvent the immune control of their hosts including subversion of the communication language between cells of the immune system provided by chemokines and other cytokines. One subversive molecule secreted in the saliva of Rhipicephalus sanguineus is Evasin‐3, a structurally unique 7 kDa protein that selectively binds the neutrophil chemoattractants, CXCL8 and (with lower affinity) CXCL1. We compared anti‐human CXCL8 and anti‐mouse CXCL1/KC activities in salivary gland extracts prepared from adult Amblyomma variegatum, Rhipicephalus appendiculatus and Dermacentor reticulatus ticks during blood‐feeding. Both anti‐CXCL8 activity and anti‐CXCL1 activity were detected in all species and in both adult females and males, with consistently higher activity levels against CXCL8. These results suggest that Evasin‐3‐like activity is common amongst metastriate ixodid tick species, and provide further evidence of the importance to ticks in controlling neutrophils during blood‐feeding. As such, Evasin‐3 offers a new target for anti‐tick vaccine development. 相似文献
8.
Sergeev IuV Molochkov VA Galil-Ogly GA Bershchanskaia AM Paklina OV 《Arkhiv patologii》2000,62(5):45-48
A case of a rare malignant tumour of the sweat glands is reported. Such tumors are often taken for visceral adenocarcinoma metastasis. The tumor was diagnosed by means of immunohistochemistry. 相似文献
9.
The review of modern achievements in morphology and genetic characteristics of pancreatic tumors with ductal phenotype is presented. Problems of intraductal pancreatic neoplasia (PanIN) as precancerous process for ductal adenocarcinoma are considered in detail. 相似文献