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981.
982.
983.
Andersen HR Schmidt IM Grandjean P Jensen TK Budtz-Jørgensen E Kjaerstad MB Baelum J Nielsen JB Skakkebaek NE Main KM 《Environmental health perspectives》2008,116(4):566-572
Objectives
The aim of this prospective study was to investigate whether occupational pesticide exposure during pregnancy causes adverse effects on the reproductive development in the male infants.Design and measurements
Pregnant women employed in greenhouses in Denmark were consecutively recruited, and 113 mother–son pairs were included. The mothers were categorized as occupationally exposed (91 sons) or unexposed (22 sons) to pesticides during pregnancy. Testicular position and volume, penile length, and position of urethral opening were determined at 3 months of age using standardized techniques. Concentrations of reproductive hormones in serum from the boys were analyzed.Results
The prevalence of cryptorchidism at 3 months of age was 6.2% [95% confidence interval (CI), 3.0–12.4]. This prevalence was considerably higher than among Danish boys born in the Copenhagen area (1.9%; 95% CI, 1.2–3.0) examined by the same procedure. Boys of pesticide-exposed mothers showed decreased penile length, testicular volume, serum concentrations of testosterone, and inhibin B. Serum concentrations of sex hormone-binding globulin, follicle-stimulating hormone, and the luteinizing hormone:testosterone ratio were increased compared with boys of nonexposed mothers. For individual parameters, only the decreased penile length was statistically significant (p = 0.04). However, all observed effects were in the anticipated direction, and a joint multivariate test showed that this finding had a p-value of 0.012.Conclusions
Our findings suggest an adverse effect of maternal occupational pesticide exposure on reproductive development in the sons despite current greenhouse safeguards and special measures to protect pregnant women. 相似文献984.
Sebastian Keil Philipp Bruners Katharina Schiffl Martin Sedlmair Georg Mühlenbruch Rolf W. Günther Marco Das Andreas H. Mahnken 《Cardiovascular and interventional radiology》2010,33(2):297-306
The purpose of this study was to investigate differences in change of size and CT value between local recurrences and tumor-free
areas after CT-guided radiofrequency ablation (RFA) of hepatic metastases during follow-up by means of dedicated software
for automatic evaluation of hepatic lesions. Thirty-two patients with 54 liver metastases from breast or colorectal cancer
underwent triphasic contrast-enhanced multidetector-row computed tomography (MDCT) to evaluate hepatic metastatic spread and
localization before CT-guided RFA and for follow-up after intervention. Sixteen of these patients (65.1 ± 10.3 years) with
30 metastases stayed tumor-free (group 1), while the other group (n = 16 with 24 metastases; 62.0 ± 13.8 years) suffered from local recurrent disease (group 2). Applying an automated software
tool (SyngoCT Oncology; Siemens Healthcare, Forchheim, Germany), size parameters (volume, RECIST, WHO) and attenuation were
measured within the lesions before, 1 day after, and 28 days after RFA treatment. The natural logarithm (ln) of the quotient
of the volume 1 day versus 28 days after RFA treament was computed: lnQ1//28/0volume. Analogously, ln ratios of RECIST, WHO, and attenuation were computed and statistically evaluated by repeated-measures ANOVA.
One lesion in group 2 was excluded from further evaluation due to automated missegmentation. Statistically significant differences
between the two groups were observed with respect to initial volume, RECIST, and WHO (p < 0.05). Furthermore, ln ratios corresponding to volume, RECIST, and WHO differed significantly between the two groups. Attenuation
evaluations showed no significant differences, but there was a trend toward attenuation assessment for the parameter lnQ28/0attenuation (p = 0.0527), showing higher values for group 1 (–0.4 ± 0.3) compared to group 2 (–0.2 ± 0.2). In conclusion, hepatic metastases
and their zone of coagulation necrosis after RFA differed significantly between tumor-free and local-recurrent ablation zones
with respect to the corresponding size parameters. A new parameter (lnQ1//28/0volume/RECIST/WHO/attenuation) was introduced, which appears to be of prognostic value at early follow-up CT. 相似文献
985.
Covert attention not only improves performance in many visual tasks but also modulates the appearance of several visual features. Studies on attention and appearance have assessed subjective appearance using a task contingent upon a comparative judgment (e.g., M. Carrasco, S. Ling, & S. Read, 2004). Recently, K. A. Schneider and M. Komlos (2008) questioned the validity of those results because they did not find a significant effect of attention on contrast appearance using an equality task. They claim that such equality judgments are bias-free whereas comparative judgments are bias-prone and propose an alternative interpretation of the previous findings based on a decision bias. However, to date there is no empirical support for the superiority of the equality procedure. Here, we compare biases and sensitivity to shifts in perceived contrast of both paradigms. We measured contrast appearance using both a comparative and an equality judgment. Observers judged the contrasts of two simultaneously presented stimuli, while either the contrast of one stimulus was physically incremented (Experiments 1 and 2) or exogenous attention was drawn to it (Experiments 3 and 4). We demonstrate several methodological limitations of the equality paradigm. Nevertheless, both paradigms capture shifts in PSE due to physical and perceived changes in contrast and show that attention enhances apparent contrast. 相似文献
986.
987.
988.
Katharina C. Kaehler Vernon K. Sondak Dirk Schadendorf Axel Hauschild 《European journal of cancer (Oxford, England : 1990)》2010,46(1):41-46
Classic interferon-α formulations have antitumour activity in a variety of neoplastic diseases, including the adjuvant and palliative setting of metastatic melanoma, as single agents or in combination with chemotherapy and/or interleukin-2. Pegylated interferon, widely used for the treatment of hepatitis, seems to be at least equally efficacious as standard recombinant interferon in the treatment of metastatic melanoma, and the available evidence suggests that equi-efficacious doses have somewhat lower acute toxicity. Moreover, the favourable pharmacokinetic properties of pegylated interferon allow the administration on a weekly basis, with sustained exposure to interferon during that entire period.Several clinical trials have been conducted testing adjuvant and palliative treatment with pegylated interferon-α in high-risk melanoma patients with promising results. The role of pegylated interferons in the setting of advanced metastatic melanoma will need further investigation in clinical trials, potentially in combination with targeted or cytotoxic agents with regard to synergistic antiangiogenic and cytotoxic effects. The use of pegylated interferons in earlier stage melanomas will be investigated in upcoming trials. 相似文献
989.
990.
Maximilian Bockhorn Jussuf T. Kaifi Sabrina Thieltges Cenap Güngör Katharina E. Effenberger Andrea Strelow Uta Reichelt Guido Sauter Klaus Pantel Jakob R. Izbicki Emre F. Yekebas 《International journal of cancer. Journal international du cancer》2010,127(8):1931-1940
Insulin‐like growth factor‐1 receptor (IGF‐1R) and human epidermal growth factor receptor‐2 (HER2) receptor expression has been found to be a key regulator of tumorigenesis. The purpose of our study was to establish the prognostic significance of IGF‐1R in esophageal cancer and to determine the effect of IGF‐1R and HER2 targeting with α‐IR3 and Herceptin? antibodies on the proliferation of esophageal cancer cells in vitro. IGF‐1R expression and clinicopathological correlations were analyzed with a tissue microarray containing 234 esophageal cancer specimens (133 adenocarcinomas and 101 squamous cell carcinomas). Proliferation changes associated with Herceptin? and α‐IR3 blockage were evaluated with the unique human esophageal cancer cell lines Pt1590 and LN1590. IGF‐1R and HER2 expression levels, activation and phosphorylation status of downstream signaling proteins involved in the activation pathways were analyzed by Western blotting. IGF‐1R overexpression was detected in 121 (52%) of the 234 esophageal tumors examined. In the subgroup of 87 HER2‐positive tumors, 93.1% showed concordant overexpression for IGF‐1R. IGF‐1R was identified as a variable associated with reduced overall survival for adenocarcinoma (p = 0.05), but not for squamous cell carcinoma. The combination of Herceptin? and α‐IR3 was more effective in inhibiting in vitro proliferation than treatment with either agent alone (p < 0.01). This was associated with a decrease in HER2 and IGF‐1R protein levels and suppression of Akt‐ and MAP kinase phosphorylation. IGF‐1R expression can be used as a novel prognostic marker for adenocarcinomas of the esophagus. Cotreatment with IGF‐1R and HER2 antibodies might become a valuable and effective treatment option in esophageal adenocarcinoma. 相似文献