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71.
72.

Purpose

Stereotactic body radiation therapy (SBRT) for hepatocellular carcinoma (HCC) has been evaluated in several recent studies. The CyberKnife® is an SBRT system that allows for real-time tracking of the tumor. The purpose of this study was to evaluate the prognostic factors for local control and overall survival following this treatment.

Patients and Methods

75 patients with 96 liver-confined HCC were treated with SBRT at the Oscar Lambret Comprehensive Cancer Center. Fiducials were implanted in the liver before treatment and were used as markers to track the lesion’s movement. Treatment response was scored according to RECIST v1.1. Local control and overall survival were calculated using the Kaplan and Meier method. A stepwise multivariate analysis (Cox regression) of prognostic factors was performed for local control and overall survival.

Results

There were 67 patients with Child-Turcotte-Pugh (CTP) Class A and eight patients with CTP Class B. Treatment was administered in three sessions. A total dose of 40–45 Gy to the 80% isodose line was delivered. The median follow-up was 10 months (range, 3–49 months). The local control rate was 89.8% at 1 and 2 years. Overall survival was 78.5% and 50.4% at 1 and 2 years, respectively. Toxicity mainly consisted of grade 1 and grade 2 events. Higher alpha-fetoprotein (aFP) levels were associated with less favorable local control (HR=1.001; 95% CI [1.000, 1.002]; p=0.0063). A higher dose was associated with better local control (HR=0.866; 95% CI [0.753, 0.996]; p=0.0441). A Child-Pugh score higher than 5 was associated with worse overall survival (HR= 3.413; 95% CI [1.235, 9.435]; p=0.018).

Conclusion

SBRT affords good local tumor control and higher overall survival rates than other historical controls (best supportive care or sorafenib). High aFP levels were associated with lesser local control, but a higher treatment dose improved local control.  相似文献   
73.
The main focus of this study is to illustrate the applicability of latent class analysis in the assessment of cognitive performance profiles during ageing. Principal component analysis (PCA) was used to detect main cognitive dimensions (based on the neurocognitive test variables) and Bayesian latent class analysis (LCA) models (without constraints) were used to explore patterns of cognitive performance among community-dwelling older individuals. Gender, age and number of school years were explored as variables. Three cognitive dimensions were identified: general cognition (MMSE), memory (MEM) and executive (EXEC) function. Based on these, three latent classes of cognitive performance profiles (LC1 to LC3) were identified among the older adults. These classes corresponded to stronger to weaker performance patterns (LC1>LC2>LC3) across all dimensions; each latent class denoted the same hierarchy in the proportion of males, age and number of school years. Bayesian LCA provided a powerful tool to explore cognitive typologies among healthy cognitive agers.  相似文献   
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Here we report the physical mapping of the rad56-1 mutation to the NAT3 gene, which encodes the catalytic subunit of the NatB N-terminal acetyltransferase in Saccharomyces cerevisiae. Mutation of RAD56 causes sensitivity to X-rays, methyl methanesulfonate, zeocin, camptothecin and hydroxyurea, but not to UV light, suggesting that N-terminal acetylation of specific DNA repair proteins is important for efficient DNA repair.  相似文献   
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Mucorales and Aspergillus are molds responsible for infections in immunocompromised patients. In this report, we describe a case of a rare extensively mixed cutaneous infection caused by Lichtheimia ramosa, Aspergillus fumigatus and Aspergillus terreus in a neutropenic patient suffering from an acute leukemia. The fatal outcome of this patient can be attributed to its hematologic malignancy, the extensive nature of the lesions and the resistance of the strains to antifungals.  相似文献   
79.
Abstract

The conformation of adducts derived from the reactions and covalent binding of the (+) and (-) enantiomers of 7β, 8α-dihydroxy-9α, 10α-epoxy-7,8,9,10-tetrahydrobenzo(a)pyrene (anti-BaPDE) with double-stranded calf thymus DNA in vitro were investigated utilizing the electric linear dichroism technique. The linear dichroism and absorption spectra of the covalent DNA complexes are interpreted in terms of a superposition of two types of binding sites. One of these conformations (site I) is a complex in which the plane of the pyrene residue is close to parallel (within 30°) to the planes of the DNA bases (quasi-intercalation), while the other (site II) is an external binding site; this latter type of adduct is attributed to the covalent binding of anti-BaPDE to the exocyclic amino group of deoxyguanine (N2-dG), while site I adducts are attributed to the 06-deoxyguanine and N6-deoxyadenine adducts identified in the product analysis of P. Brookes and M.R. Osborne (Carcinogenesis (1982) 3, 1223–1226). Site II adducts are dominant (~90% in the covalent complexes derived from the (+) enantiomer), but account for only 50±5% of the adducts in the case of the (—)-enantiomer. The orientation of site II complexes is different by 20±10° in the adducts derived from the binding of the (+) and the (—) enantiomers to DNA, the long axis of the pyrene chromophore being oriented more parallel to the axis of the DNA helix in the case of the (+) enantiomer. These findings support the proposals by Brookes and Osborne that the difference in spatial orientation of the N2-dG adducts of (-)-anti-BaPDE together with their lower abundance may account for the lower biological activity of the (—) enantiomer. The external site II adducts, rather than site I adducts, appear to be correlated with the biological activity of these comoounds.  相似文献   
80.
A small group of nine nominal species belonging to the genus Neacratus Alonso-Zarazaga, Lyal, Sforzi & Bartolozzi, 1999 is studied in detail from a morphological point of view. Lectotypes are designated for Brentus obtusus Lund, 1800 and Nemocephalus fulgidus Kleine, 1928. Three new synonymies are proposed: Nemocephalus brevicostatus Kleine, 1922 n. syn. for Brenthus obtusus Lund, 1800, Nemocephalus longiceps Perroud, 1853 n. syn. for Brenthus famulus Boheman, 1840, and Nemocephalus fulgidus Kleine, 1928 n. syn. for B. famulus Boheman, 1840. A new species, Neacratus pascali n. sp., is described from French Guiana. New country records are provided for Neacratus obtusus (Bolivia, Ecuador, French Guiana, Grenada, Peru, Trinidad and Tobago, Venezuela), N. puncticeps (Sharp, 1895) (Colombia, Ecuador, Venezuela), N. guatemalensis (Senna, 1893) (Belize, Colombia, El Salvador), N. deplanatus (Sharp, 1895) (Colombia, Costa Rica, French Guiana, Mexico, Panama, Venezuela) and N. famulus (Paraguay). A phylogenetic analysis carried out on this group shows it forms a monophyletic lineage included in a clade containing most of other species of Neacratus, of which it is the type species; it is therefore not justified to create a new generic name. The possible polyphyletism of the genus Neacratus as a whole and the development of an excessively long rostrum in some male Acratini are discussed.  相似文献   
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