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BACKGROUND: Comprehensive literature on cervical cancer demonstrates, even today, the need for optimization of the timing of external-beam radiotherapy (EBRT) and high-dose-rate brachytherapy (HDR-BT) in the treatment of stage IIA/B-IIIB cervical carcinoma. PATIENTS AND METHODS: 210 patients with carcinoma of the cervix were treated in the Municipal Center of Oncoradiology between January 1991 and December 1996 (FIGO IIA: n = 10, FIGO IIB: n = 113, and FIGO IIIB: n = 87). Two regimens were compared: sequential radiation therapy (SRT) with 4 x 8 Gy HDR-BT to point A followed by EBRT, and continuous radiation therapy (CRT) in which 5 x 6 Gy HDR-BT to point A, one session per week, was integrated into the EBRT. A total dose of 68-70 Gy to point A and 52-54 Gy to point B was given in EBRT with SRT, five fractions per week were applied. Four fractions per week were applied in CRT, i. e., no EBRT was performed on the day of HDR-BT. Total doses to points A and B were identical in both regimens. Overall treatment time (OTT) amounted to 56 days for SRT and 35 days for CRT. Median follow-up time was 3.4 (2.5-4.2) years. RESULTS: Progression-free 5-year-survival (PFS) was 71% in the CRT and 56% in the SRT group. Nevertheless, this difference was not statistically significant (p = 1.00), and the same was found in a subgroup analysis of the different tumor stages, showing, however, an unequivocal trend. Late bladder and rectal injuries occurred in 13% and 25%, respectively. Late rectal injuries were significantly more frequent with SRT than CRT (35 patients in the SRT and 18 patients in the CRT group; p = 0.037). This was due to the higher doses per fraction of HDR-BT in the SRT group. No difference was found regarding late bladder injuries (p = 0.837). CONCLUSION: For the patients included in this study, no advantage has been found so far in using CRT, i. e., shortening the OTT by weekly integration of HDR-BT into EBRT. Nevertheless, an obvious trend exists. The dose of 8 Gy per fraction of HDR-BT in the SRT regimen was obviously too high. To achieve a significant improvement in local control and disease-free survival (DFS) as well as overall survival (OS), the combination with modern chemotherapy regimens and regional deep hyperthermia may rather be the treatment option.  相似文献   
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Potent inhibition of HIV-1 entry by (s4dU)35   总被引:2,自引:0,他引:2  
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Autocrine motility factor (AMF) is one of the motility cytokines regulating tumor cell migration, therefore identification of the signaling pathway coupled with it has critical importance. Previous studies revealed several elements of this pathway predominated by lipoxygenase-PKC activations but the role for tyrosine kinases remained questionable. Motility cytokines frequently have mitogenic effect as well, producing activation of overlapping signaling pathways therefore we have used B16a melanoma cells as models where AMF has exclusive motility effect. Our studies revealed that in B16a cells AMF initiated rapid (1–5 min) activation of the protein tyrosine kinase (PTK) cascade inducing phosphorylation of 179, 125, 95 and 40/37 kD proteins which was mediated by upstream cyclo- and lipoxygenases. The phosphorylated proteins were localized to the cortical actin-stress fiber attachment zones in situ by confocal microscopy. On the other hand, AMF receptor activation induced significant decrease in overall serine-phosphorylation level of cellular proteins accompanied by serine phosphorylation of 200, 90, 78 and 65 kd proteins. The decrease in serine phosphorylation was independent of PTKs, PKC as well as cyclo- and lipoxygenases. However, AMF induced robust translocation of PKCα to the stress fibers and cortical actin suggesting a critical role for this kinase in the generation of the motility signal. Based on the significant decrease in serine phosphorylation after AMF stimulus in B16a cells we postulated the involvement of putative serine/threonine phosphatase(s) upstream lipoxygenase and activation of the protein tyrosine kinase cascade downstream cyclo- and lipoxygenase(s) in the previously identified autocrine motility signal. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
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Voluntary and forced exercise decrease morbidity and mortality in laboratory animals. Caloric restriction has similar effects on health and unique benefits on life span. Nonetheless, in most experiments, animals do not have access to physical activity and are fed ad libitum (AL). We hypothesized that with regular access to either unlimited running wheel exercise (EX) or limited physical activity (PA), key biomarkers of health would be enhanced enough to counter some consequences of a sedentary AL lifestyle. This 16-month study compared body weight, tumor number and size, tissue lesions, oxidative stress, and reactive stress in (1) sedentary animals with no access to physical activity (SED); (2) animals with access to hour-long, twice weekly activity in a large box (PA); and (3) animals with access every other day to a running wheel (EX). At the end of the study, EX body weight was 8-9% lower than PA and SED. In addition, EX had no kidney lesions versus 50% in PA and SED, and had smaller tumor size (10+/-2 vs. 14+/-4 and 30+/-4 mm). Exhaustive exercise lowered glutathione/oxidized glutathione ratio in EX and PA, but in SED, the ratio was depressed even in resting animals. In all treatments, prolactin (PRL) levels were lower in resting animals than in acutely exercised animals. In conclusion, EX had the most favorable health biomarkers while SED had the least. PA did not confer gross health benefits different than the SED group, but was biochemically more similar to EX animals.  相似文献   
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Emotion dysregulation and intimacy problems are theoretically underpinned correlates of hypersexuality (i.e., uncontrollable sexual urges, fantasies, and behaviors resulting in distress and impairment in different areas of functioning), but the directionality of these associations has not been established, as work in this area has relied on cross-sectional designs. Moreover, although hypersexuality may have significant adverse effects on romantic relationships and approximately half of treatment-seeking individuals are in a relationship, prior studies almost exclusively involved samples of men, regardless of their relationship status. The aim of the present study was to examine the directionality of associations between both partners’ emotion dysregulation, physical (i.e., partnered sexual frequency) and relationship intimacy, and hypersexuality using a longitudinal, dyadic framework. Self-reported data of 267 mixed-sex couples (Mage_men?=?29.9 years, SD?=?8.2; Mage_women?=?27.7 years, SD?=?6.7) at baseline (T1) and six-month follow-up (T2) were analyzed using a crossed-lagged model within an actor–partner interdependence framework. Prior greater emotion dysregulation (T1) in both men and women was associated with their own later greater hypersexuality (T2). Women’s prior greater hypersexuality (T1) was associated with their later lower relationship intimacy (T2). Lower levels of intimacy were not significantly associated with later hypersexuality. No partner effects were found in relation to hypersexuality. Findings suggest that men and women may use sexual behaviors to cope with negative emotions, which could, in turn, lead to hypersexuality. Intimacy problems did not precede hypersexuality, although women’s hypersexuality may reduce their own relationship intimacy over time.

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8.
The response to bromoergocryptine (Parlodel, Sandoz) was examined in 42 pathospermic patients. The authors conclude that Parlodel did not influence the spermiogram considerably. Serum prolactin levels were lowered significantly, while the FSH, LH, testosterone, 17--hydroxyprogesterone and 17--oestradiol concentrations did not change. Improvement was reported in potentia coeundi in one third of the patients.Supported by the Scientific Research Council, Ministry of Health, Hungary (4-29-0302-01-2/S).  相似文献   
9.
We report the first isolation and characterization of several Enterobacteriaceae strains harboring blaNDM-1, blaOXA-48 and/or blaOXA-181 genes in a Romanian emergency teaching hospital. Between January 2010 and September 2012 nine carbapenemase-producing Enterobacteriaceae strains were identified. The blaNDM-1 gene was present in two Enterobacter cloacae strains, an Escherichia coli and two Klebsiella pneumoniae strains. One of these K. pneumoniae strains also harbored the blaOXA-181 gene. Three other K. pneumoniae strains and one Serratia marcescens carried blaOXA-48.  相似文献   
10.
Severe chronic hepatic injury can induce complex reparative processes. Ductular reaction and the appearance of small hepatocytes are standard components of this response, which is thought to have both adverse (e.g. fibrosis, carcinogenesis) and beneficial (regeneration) consequences. This complex tissue reaction is regulated by orchestrated cytokine action. We have investigated the influence of the tyrosine kinase inhibitor imatinib on a regenerative process. Ductular reaction was induced in mice by the widely used choline‐deficient ethionine‐supplemented diet (CDE). Test animals were treated daily with imatinib. After 6 weeks of treatment, imatinib successfully reduced the extent of ductular reaction and fibrosis in the CDE model. Furthermore, the number of small hepatocytes increased, and these cells had high proliferative activity, were positive for hepatocyte nuclear factor 4 and expressed high levels of albumin and peroxisome proliferator‐activated receptor alpha. The overall functional zonality of the hepatic parenchyma (cytochrome P450 2E1 and glucose 6 phosphatase activity; endogenous biotin content) was maintained. The expression of platelet‐derived growth factor receptor beta, which is the major target of imatinib, was downregulated. The anti‐fibrotic activity of imatinib has already been reported in several experimental models. Additionally, in the CDE model imatinib was able to enhance regeneration and preserve the functional arrangement of hepatic lobules. These results suggest that imatinib might promote the recovery of the liver following parenchymal injury through the inhibition of platelet‐derived growth factor receptor beta.  相似文献   
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