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1.
Abstract

This study was undertaken to compare the concentrations of pro- and anti-angiogenic growth factors, nitric oxide (NO) stable metabolites in maternal serum and embryonic left ventricular (LV) isovolumic relaxation time (IRT, ms) during the first trimester in two groups of women: with pregnancy conceived by assisted reproductive technologies (ART, n?=?39) and normally conceived (control group, n?=?68) pregnancy. The concentration of vasoconstrictor endothelin 1 was 45.5 times more in ART than in control group. On the contrary, the concentrations of NO stable metabolites in ART were 1.9 times less than in control women. The assessment of angiogenic suppressors in ART women demonstrates the decrease in s-endoglin concentration was 1.6 times and in soluble receptor to vascular endothelial growth factor concentration was 2.0 times in comparison with control group. There was a significant increase in LV IRT in ART embryos in comparison to control ones. These data suggest significant changes in pro- anti-angiogenic factors balance and increase in vascular impedance in ART-conceived embryos.  相似文献   
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59 angiomyolipomas were studied: immunohistochemistry (IHC) was used in 24 cases, electron microscopy (EM) in 6 cases. 57 tumors had a typical structure, 2 did not contain fat component. Premelanosomes were found by EM in one tumor. Smooth muscle actin was found in all tumor cells. Involvement of lymph nodes was observed in 2 patients. Histogenesis of this tumor is discussed.  相似文献   
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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.   相似文献   
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Associations of a new human herpesvirus type 8 (HHV-8) with different forms of Kaposi's sarcoma (KS) in Russia have been studied. Search for this virus genetic information has been carried out in biopsy specimens of benign and malignant tumors other than KS, and probable sites of HHV-8 latency in human body have been checked. HHV-8 sequences were detected by polymerase chain reaction (PCR). HHV-8 sequences were most often detected in idiopathic (80.6%), AIDS-associated (80%), and immunosuppressive (100%) KS. The results indicate a selective association of HHV-8 with KS. No probable sites of the virus latency were detected in peripheral blood cells of patients with KS and in the prostate of patients with chronic prostatitis. The only exception was the husband of a patient with KS: HHV-8 sequences were detected in his prostatic secretion by nested PCR.  相似文献   
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Results of cytological diagnosis in the static telepathology mode are analyzed. Three expert cytologists made the diagnosis on the basis of images of cytological preparations obtained from 94 patients with tumors of soft tissues and bones. A total of 113 diagnoses were correct: benign or malignant type of the tumor and its histological type were identified. In general, a total of 152 (88.9%) diagnoses were correct as regards their significance for treatment strategy. Errors classified as groups 3 and 4 were the most significant (erroneous assessment of tumor type--benign or malignant--in 6.4% cases). Analysis of discrepancies between cytological and pathoanatomical diagnoses and data of routine optic microscopy of similar cytological preparations of the same material (bone and soft tissue tumors) showed the same value: 6.8% of cytological and pathoanatomical diagnoses were at disagreement (groups 3 and 4 of errors). Therefore, telepathology can be resorted to for consultations and discussion of obscure cases. It is particularly important for a morphologist to discuss complex cases by means of telepathology at a specialized institution, distant from him or her.  相似文献   
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