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31.
Clear cell carcinoma originating in the abdominal wall is rare and usually develops within endometriotic implants in the scar. We describe 2 patients: a 42 year old with a 15 cm mass on the abdominal wall treated with neoadjuvant chemotherapy and excision and a 51 year old with a 6 cm abdominal mass treated with excision and adjuvant radiotherapy.  相似文献   
32.

Objective

GLUT-1 is involved at various steps in the processes of tumor progression. The objective of this study was to examine the relationship between GLUT-1 expression and tumor proliferation and angiogenesis in epithelial ovarian carcinoma.

Materials and methods

Specimens from 213 patients with epithelial ovarian carcinoma were evaluated by immunohistochemistry for GLUT-1, Ki-67, and vascular endothelial growth factor. Tumor microvessel density was assessed with CD34 immunostaining. We investigated the relationships between GLUT-1 expression and clinicopathologic characteristics, tumor angiogenesis (tumor MVD and vascular endothelial growth factor expression), and tumor proliferation (Ki-67). The effect of GLUT-1 expression on patient survival and on the volume of residual disease after cytoreduction was determined.

Results

There was a significant positive correlation between expression of GLUT-1, Ki-67, and microvessel density. In univariate survival analysis, high GLUT-1 expression, high Ki-67 expression and high tumor microvessel density showed a significant impact on patient survival (p = 0.0001). In multivariate analysis including patients with all tumor stages, after controlling for age, race, stage, grade, MVD, and the 3 markers (GLUT-1, Ki-67 and VEGF), only age (HR 1.5; 95% CI 1-2.3), stage (HR 3.6; 95% CI 1.8-7.5) and grade (HR 2.3; 95% CI 1.2-4.5) retained their significance as independent poor prognostic factors. Tumors simultaneously overexpressing GLUT-1 and Ki-67 were less likely to be optimally cytoreduced as compared to tumors overexpressing only one or neither of those two markers (OR: 3.8, p = 0.01).

Conclusion

Expression of GLUT-1 correlates with tumor proliferation and microvessel density in epithelial ovarian carcinoma. In addition, patients with rapidly proliferating advanced stage tumors overexpressing GLUT-1 have a lesser chance for optimal cytoreduction.  相似文献   
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A number of studies have suggested that the pedunculopontine tegmental nucleus (PPTg) may play a role in reward-related behaviour. The present study was intended to investigate this further using conditioned place preference. In conditioned place preference paradigms the amount of time spent in a preferred environment is proportional to the value of the reinforcement present, until a maximum is reached. In the present experiments we aimed to determine whether this relationship was affected by lesions of the PPTg by examining the formation of a conditioned place preference to either 4%, 12% or 20% sucrose solutions in food-deprived PPTg lesioned rats. The conditioned place preference apparatus had two compartments different in colour, smell and floor texture. During conditioning, rats were restricted to one compartment or the other, one of which was paired with sucrose. This was carried out during 30 min sessions, alternating conditioned or nonconditioned trials for 14 days. On the test day, rats were given access to both compartments through a connecting chamber, and were scored for side preference over 15 min. Both PPTg and sham lesioned rats showed a conditioned place preference to 12% and 20% sucrose, but no place preference was formed by either group to 4% sucrose. There was no significant difference between the groups in the place preference shown. Consumption of 4% sucrose was not affected by excitotoxic lesions of the PPTg, but PPTg lesioned rats consumed significantly more 12% and 20% sucrose than sham controls. This suggests that perception of reward value, as judged by CPP formation, is unchanged by excitotoxic lesions of the PPTg. The increased consumption of 12% and 20% sucrose shown by rats bearing such lesions is therefore not likely to be a product of altered reward perception.  相似文献   
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Genetic aberrations, such as loss of heterozygosity (LOH) and mutations leading to functional inactivation of the PTEN tumor suppressor gene, located on chromosome 10q23.3, have been shown to be associated with approximately one third of ovarian adenocarcinomas. In addition, microsatellite instability (MSI) leading to the functional inactivation of the PTEN gene has also been reported for ovarian adenocarcinomas with frequencies varying from 6 to 37%. However, the frequency of PTEN gene abnormalities has not been well studied or evaluated in lesions such as typical and atypical endometriosis. The aim of this study was to investigate a possible sequential progression from endometriosis through atypical endometriosis to ovarian carcinoma by assessing LOH at 10q23.3 and MSI in those entities. Genomic DNA was analyzed for LOH and MSI at 3 loci on chromosome 10, using polymerase chain reaction amplification. Significant differences in LOH were seen between endometriosis (4.3%) and ovarian carcinoma (23.5%) at D10S608. The differences at the other 2 loci were not significant. A high frequency of MSI was found in endometriosis (82.6%) and atypical endometriosis (75%); however, the differences were not significant. These results suggest that LOH at D105608 may possibly be an important molecular event in the progression of endometriosis to carcinoma. This study highlights that endometriosis and atypical endometriosis might act as precursor lesions that have the potential to progress into ovarian adenocarcinoma.  相似文献   
37.
Abstract  Failure of the hepatic al-lograft continues to be a serious life-threatening risk for the recipient. Because no effective method of ex-tracorporeal support is available for these patients, early retransplanta-tion is the only alternative that offers the potential for survival. The aim of this prospective analysis was to search for a predictor of primary non-function of hepatic allografts before reperfusion. From March to June 1993 we investigated 19 liver biopsies which were obtained during the preparation of the donor liver in the back table bath immediately before the implantation of the organ. All organs were preserved by UW solution. Biopsies were stored at -80°C, the working-up process was started by dividing the biopsy into several portions for the determination of fat (petrol-ether extraction), water (weighing before thawing and after drying) and free amino acids (OPA-HPLC method). Graft function was categorized into three groups: (1) good function; (2) fair function; (3) primary non-function (PNF). In addition to known risk factors for delayed graft function such as a long stay of the donor in intensive care and a prolonged an-hepatic period of the recipient, we were able to demonstrate that organs with malfunction had a higher fat and water content. Donor livers developing PNF showed a trend towards higher total and subdivided amino acids, which could be explained by the incapacity of the liver to utilize available substrates for gluconeogenesis.  相似文献   
38.
We make a review of the factors contributing to microleakage around dental restorations and the biological effects that this produces. We also make an evaluation of the existing methods for its research. We analize the behaviour of the different restorative materials, in relation to microleakage, and we set the rules to minimize this inevitable event that affects so much the longevity of dental restorations.  相似文献   
39.

Background Antibiotic resistance has reached an alarming rate globally especially in middle-income countries such as Lebanon. The development of antibiotic resistance is strongly linked to the increased population’s injudicious consumption of antibiotics. Objective This study aims to explore the trends of antibiotics consumption in the Lebanese community, between 2004 and 2016, to inform rational use of antibiotics. Setting The study was performed using the Intercontinental Marketing Statistics (IMS) Health Lebanon database Method This is an observational longitudinal study conducted through a review of the IMS database. The annual antibiotics consumption was determined by the Defined Daily Dose (DDD)/1000 inhabitants/day (DID). The trends of antibiotics consumption were then categorized by antibiotic class and spectrum of activity. Main outcome measure The total consumption of antibiotics in Lebanon and the classes of antibiotics used by the community. Results Total community consumption of antibiotics, measured by DDD/1000 inhabitants/day (DID), significantly increased from 18.71 in 2004 to 31.26 in 2016. Penicillin combinations, quinolones, third-generation cephalosporins, tetracyclines, and carbapenems showed significant uptrends, in contrast to first-generation cephalosporins, sulfonamides and diaminopyrimidines, and beta-lactamase resistant penicillins. Broad-spectrum antibiotics showed a marked increase in their consumption from 11.50 DID in 2004 to 22.51 DID in 2016 whereas intermediate-spectrum antibiotics had only a slight increase in their consumption from 7.18 DID in 2004 to 8.51 DID in 2016, and narrow-spectrum antibiotics had a severe decline in their consumption from 0.006 DID in 2004 to 0.0003 DID in 2016. Conclusion There is an alarming increase in antibiotics consumption in Lebanon, particularly broad-spectrum antibiotics. This should be complemented with evidence on the determinants of antibiotic consumption such as prescriber and patient-related factors and drug promotional activities to minimize antibiotics overuse.

  相似文献   
40.
In 2015, we founded Pedi Lyme Net, a pediatric Lyme disease research network comprising 8 emergency departments in the United States. Of 2,497 children evaluated at 1 of these sites for Lyme disease, 515 (20.6%) were infected. This network is a unique resource for evaluating new approaches for diagnosing Lyme disease in children.  相似文献   
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