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21.
The frequency of chromosomal aberrations (CAs) was evaluated in blood lymphocytes from 18 healthy subjects. Basal CA frequencies were not significantly different in GSTM1 positive and GSTM1 null subjects (P>0.05), whereas they were considerably higher in smokers than in non-smokers. After 1 Gy dose of X-ray challenge of blood samples, CA frequencies were significantly higher in GSTM1 null subjects, compared to GSTM1 positive subjects (P<0.005), and in smokers, compared to non-smokers. These effects are ascribed to the influence of GSTM1 genotype and of smoking status on DNA repair capacities. As the induction of CAs are associated with carcinogenesis, the challenge assay is able to detect enhanced susceptibility for CA caused by genetic predisposition of DNA repair deficiency.  相似文献   
22.
Smooth muscle cells (SMC) are exposed to fluid shear stress because of transmural (interstitial) flow across the arterial wall. This shear stress may play a role in the myogenic response and flow-mediated vasomotion. We, therefore, examined the effects of fluid flow on contraction of rat aortic SMC. SMC that had been serum-starved to induce a contractile phenotype were plated on quartz slides and exposed to controlled shear stress levels in a flow chamber. The area of the cells was quantified, and reduction in the cell area was reported as contraction. At 25 dyn/cm(2), significant area reduction was apparent 3 min after the onset of flow and exceeded 30% at 30 min. At 1 dyn/cm(2), significant contraction was not observed at 30 min. The threshold for significant shear-induced contraction appeared to be 11 dyn/cm(2). The signal transduction mechanism was studied at 25 dyn/cm(2). Intracellular calcium was imaged by using the calcium-sensitive fluorescent dye fura 2-AM. There was no detectable change in intracellular calcium during 10 min of exposure to shear stress, even though the cells displayed a significant calcium response to thapsigargin, calcium ionophore, and KCl. Further studies using pathway inhibitors provided evidence that the most important signal transduction pathway mediating calcium-independent contraction in response to fluid flow is the Rho-kinase pathway, although there was a suggestion that protein kinase C plays a secondary role.  相似文献   
23.
Arterial distribution of the upper lip was investigated in this study. The location, course, length, and diameter of the superior labial artery and its alar and septal branches were determined on 14 preserved cadaver heads. Another cadaver head was used to show the arterial tree by the colored silicone injection technique. The superior labial artery was the main artery of the upper lip and always originated from the facial artery. The superior labial artery was 45.4 mm in length, with a range from 29 to 85 mm. The mean distance of the origin of the superior labial artery from the labial commissura was 12.1 mm. The superior labial artery was 1.3 mm in external diameter at its origin. The mean distance of origin of the superior labial artery from the lower border of the mandible was 46.4 mm. The alar division of the superior labial artery was mostly found as a single branch (82 percent). Its mean length was 14.8 mm and the mean diameter at the origin was 0.5 mm. The distance between the origins of the superior labial artery and the septal branch was 33.3 mm. The septal branch was single in most of the cases (90 percent). The mean length of the septal branch was 18.0 mm and the diameter at its origin was 0.9 mm. After all dissections, it was concluded that the arterial distribution of the upper lip was not constant. The superior labial artery can occur in different locations unilaterally and bilaterally, with the branches showing variability.  相似文献   
24.
The submental artery island flap is a versatile option in head and neck reconstruction. This flap may be used for the coverage of perioral, intraoral, and other facial defects, leaving a relatively acceptable donor-site scar. In this study, the submental region of 13 formalin-fixed cadavers was dissected bilaterally. Comprehensive anatomical information regarding the pedicle of the flap and its relationship with the important adjacent structures is provided. The mean values of the measurements of the facial and submental arteries were as follows: the facial artery was 2.7 mm in diameter at the origin, and it crossed the mandibular border 26.6 mm from the mandibular angle. The origin of the submental artery was 27.5 mm from the origin of the facial artery, 5.0 mm from the mandibular border, and 23.8 mm from the mandibular angle. The diameter of the submental artery was 1.7 mm at the origin. The artery was found mostly to course superficial to the submandibular gland. In one case, the artery passed through the gland. The total length of the submental artery was 58.9 mm. The artery anastomosed with the contralateral artery in 92 percent of the cadavers. The submental artery was deep to the anterior belly of the digastric muscle in 81 percent of the cases. This study presents detailed anatomical data about the location, dimension, and relationship of the facial artery, the submental artery, and the submental vein that may be useful during dissection of the submental artery island flap.  相似文献   
25.
Extremely low frequency (ELF) electromagnetic field (EMF) is thought to prolong the life of free radicals and can act as a promoter or co-promoter of cancer. 8-hydroxy-2'-deoxyguanosine (8OHdG) is one of the predominant forms of radical-induced lesions to DNA and is a potential tool to asses the cancer risk. We examined the effects of extremely low frequency electro magnetic field (ELF-EMF) (50 Hz, 0.97 mT) on 8OHdG levels in DNA and thiobarbituric acid reactive substances (TBARS) in plasma. To examine the possible time-dependent changes resulting from magnetic field, 8OHdG and TBARS were quantitated at 50 and 100 days. Our results showed that the exposure to ELF-EMF induced oxidative DNA damage and lipid peroxidation (LPO). The 8OHdG levels of exposed group (4.39+/-0.88 and 5.29+/-1.16 8OHdG/dG.10(5), respectively) were significantly higher than sham group at 50 and 100 days (3.02+/-0.63 and 3.46+/-0.38 8OHdG/dG.10(5)) (p<0.001, p<0.001). The higher TBARS levels were also detected in the exposure group both on 50 and 100 days (p<0.001, p<0.001). In addition, the extent of DNA damage and LPO would depend on the exposure time (p<0.05 and p<0.05). Our data may have important implications for the long-term exposure to ELF-EMF which may cause oxidative DNA damage.  相似文献   
26.
Incident photon conversion efficiency of the absorbing materials at either side of a thin film solar module can be enhanced by integrating a plasmonic interface. Silver nanoparticles represent a good candidate that can be integrated to a thin film solar cell for efficient light-trapping. The aim of this work is to fabricate plasmonically active interface consisting of Ag nanoparticles embedded in Al:ZnO that has the potential to be used at the front surface and at the back reflector of a thin film solar cell to enhance light-trapping and increase the photoconversion efficiency. We show that Ag can readily dewet the Al:ZnO surface when annealed at temperatures significantly lower than the melting temperature of Ag, which is beneficial for lowering the thermal budget and cost in solar cell fabrication. We find that such an interface fabricated by a simple dewetting technique leads to plasmonic resonance in the visible and near infrared regions of the solar spectrum, which is important in enhancing the conversion efficiency of thin film solar cells.  相似文献   
27.
Highlights? Detailed analysis of diet-induced obesity in more than 100 inbred mouse strains ? Identification of 11 genetic loci associated with obesity and dietary responsiveness ? Significant overlap between mouse loci with human GWAS loci for obesity ? Strain-specific shifts in gut microbiota composition in response to dietary intervention  相似文献   
28.
Onal  Merih  Kocak  Nadir  Duymus  Fahrettin  Bozkurt  Mete Kaan  Elsurer  Cagdas  Erdur  Omer  Onal  Ozkan 《Molecular biology reports》2021,48(7):5579-5586
Molecular Biology Reports - Tonsil tissue is a very important component of the human immunity system, contributing to the functioning of the cellular and humoral defence system, especially in...  相似文献   
29.

Background

The increasing incidence and heterogeneous behavior of intestinal neuroendocrine tumors (iNETs) pose a clinicopathological challenge. Our goal was to decribe the prognostic value of the new WHO 2010 grading and the AJCC/UICC TNM staging systems for iNETs. Moreover, outcomes of patients treated with somatostatin analogs were assessed.

Methods

We collected epidemiological and clinicopathological data from 93 patients with histologically proven iNETs including progression and survival outcomes. The WHO 2010 grading and the AJCC/UICC TNM staging systems were applied for all cases. RECIST criteria were used to define progression. Kaplan-Meier analyses for progression free survival (PFS) and overall survival (OS) were performed.

Results

Mean follow-up was 58.6 months (4–213 months). WHO 2010 grading yielded PFS and disease-specific OS of 125.0 and 165.8 months for grade 1 (G1), 100.0 and 144.2 months for G2 and 15.0 and 15.8 months for G3 tumors (p = 0.004 and p = 0.001). Using AJCC staging, patients with stage I and II tumors had no progression and no deaths. Stage III and IV patients demonstrated PFS of 138.4 and 84.7 months (p = 0.003) and disease-specific OS of 210.0 and 112.8 months (p = 0.017). AJCC staging also provided informative PFS (91.2 vs. 50.0 months, p = 0.004) and OS (112.3 vs. 80.0 months, p = 0.005) measures with somatostatin analog use in stage IV patients.

Conclusion

Our findings underscore the complementarity of WHO 2010 and AJCC classifications in providing better estimates of iNETS disease outcomes and extend the evidence for somatostatin analog benefit in patients with metastatic disease.  相似文献   
30.
By careful analysis of experimental X-ray ligand crystallographic protein data across several inhibitor series we have discovered a novel, potent and selective series of iNOS inhibitors exemplified by compound 8.  相似文献   
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