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61.

Purpose

to evaluate the role of whole brain radiotherapy (WBRT) and radiation boost (RB) for 208 patients recursive partitioning analysis (RPA) II with 1 or 2 brain metastases (BM) at a single institution.

Methods and Materials

the dose of WBRT was 30 Gy (10 fractions of 3 Gy). One hundred thirty-two patients (63.5%) benefited from RB of 9 Gy in 3 fractions of 3 Gy at the metastatic site. Patients had 1 or 2 BM in 122 (58.7%) and 86 cases (41.3%), respectively.

Results

patients with one or two metastases had similar survival (4.6 and 5.1 months, respectively) (p = 0.4). Median overall survival (OS) for patients treated with WBRT and RB, and with WBRT alone was 5.9 and 3.7 months, respectively (p = 0.03). The 6-, 12- and 24-month OS rates after WBRT and RB were 48.5%, 25% and 10.6%, respectively, while WBRT alone resulted in OS rates of 34%, 22.4% and 3.2%, respectively (p = 0.03). After WBRT and RB, the 6-, 12- and 24-month local control rates were 92%, 82% and 67%, respectively, while they were 81.2%, 75% and 37.5%, respectively, after WBRT alone (p = 0.03). The 6-, 12- and 24-month brain control rates after WBRT and RB were 88.7%, 75.8% and 62%, respectively, and after WBRT alone they were 78.5%, 59% and 37.7%, respectively (p = 0.03).

Conclusion

additional boost delivered with 3D conformal radiotherapy improves local and brain control rates significantly as well as overall survival for RPA II patients with 1 or 2 unresectable BM.  相似文献   
62.
In the present study, we report enhanced antimicrobial properties of 29 and 23 nm silver nanoparticles (Ag NPs) obtained by electrochemical synthesis in poly(amide-hydroxyurethane) media. Antibacterial activity assessed by disk diffusion method indicates that silver nanoparticles produced inhibition zones for both Escherichia coli and Staphylococcus aureus depending on silver concentration. The bacterial growth curve performed in the presence of silver nanoparticles showed a stronger antibacterial effect at lower concentrations than those described in the earlier reports. The effect was both dose and size dependent and was more pronounced against Gram negative bacteria than Gram positive one. The smallest Ag NPs used had a bactericidal effect resulting in killing E. coli cells. Scanning electron microscopy analysis indicated major damage and morphology changes of the silver nanoparticles treated bacterial cells. The major mechanism responsible for the antibacterial effect probably consists in clusters formation and nanoparticles anchorage to the bacterial cell surface.  相似文献   
63.
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65.
Controlled Suzuki–Miyaura coupling polymerization of 7′‐bromo‐9′,9′‐dioctyl‐fluoren‐2′‐yl‐4,4,5,5‐tetramethyl‐[1,3,2]dioxaborolane initiated by bromo(4‐tert‐butoxycarbonylamino‐phenyl)(tri‐tert‐butylphosphine)palladium ( 1 ) or bromo(4‐diethoxyphosphoryl‐phenyl)(tri‐tert‐butylphosphine)palladium ( 2 ) yields functionalized polyfluorenes (Mn = 4 × 103 g mol?1, Mw/Mn < 1.2) with a single amine or phosphonic acid, respectively, end‐group. High temperature synthesis of cadmium selenide quantum dots with these functionalized polyfluorenes as stabilizing ligands yields hybrid particles consisting of good quality (e.g. emission full width at half maximum of 30 nm; size distribution σ < 10%) inorganic nanocrystals with polyfluorene attached to the surface, as corroborated by transmission electron microscopy analysis and analytical ultracentrifugation. Sedimentation studies on particle dispersions show that a substantial portion (ca. half) of the phosphonic acid terminated polyfluorene ligands is bound to the inorganic nanocrystals, versus ca. 5% for the amino‐functionalized polyfluorene ligands. Single particle micro‐photoluminescence spectroscopy shows an efficient and complete energy transfer from the polyfluorene layer to the inorganic quantum dot.  相似文献   
66.
We examined the hindlimb lymph insulin profile during simulated intravenous glucose tolerance tests (IVGTTs) in anesthetized dogs to test the following hypotheses: 1) the biphasic insulin response to intravenous glucose can be seen as a priming bolus and a secondary infusion that effect a rapid stepwise increase in the interstitial insulin concentration and 2) the activation of glucose utilization (rate of glucose uptake [Rd]) during an IVGTT is more similar to the dynamics of the interstitial insulin profile than that of the arterial plasma. Three insulin profiles were infused: a normal biphasic pattern, a second phase infusion only, and a biphasic pattern with a fourfold greater first phase and a normal second phase. During the normal biphasic infusion, lymph insulin quickly reached and maintained a steady-state concentration (10 min, 26.42 +/- 0.86 microU/ml). With second phase only, it took lymph insulin 35 min to reach a steady state of lower concentration (13.13 +/- 0.46 microU/ml) than the normal. And with a fourfold greater first phase, lymph insulin plateaued quickly (16 min, 140.87 +/- 1.68 microU/ml), but for a shorter duration than the normal. For each profile, the time course of activation of Rd did not follow the time course of insulin in the plasma, but was more similar to that of insulin in the interstitial fluid. These results show that the biphasic response allows interstitial insulin to rapidly reach and maintain a steady state beneficial to activation and maintenance of glucose utilization.  相似文献   
67.
Laminar steady compressible flow between close rotating thermally conducting axisymmetric disks with inflow was investigated by means of a numerical solution of the Navier-Stokes equation and an asymptotic analysis. The approximate solution, obtained for small ?, E and H (Rossby and Ekman numbers, and height/radius, respectively) is valid for “merged”, “close” and “separate” boundary layers on the disks, corresponding to β? 1, β ? 1 and β? 1, respectively (where β = H2Eρ, and ρ is the non-dimensional density). These three cases may appear simultaneously in different regions of the same system due to the large variation of ρ in the radial direction. The small ? (i.e. negligible convection terms) does not necessarily imply small perturbations of the pressure, and a special treatment of the pressure term was used in order to account for this feature, which sometimes culminates in inversion of the radial pressure gradient. Thenumerical solution was obtained by a finite-difference, modified Cheng-Allen method, using a non-uniform mesh. The numerical and the approximate solution are in good agreement.  相似文献   
68.
An automated method, based on the principle of simulated annealing,is presented for determining the three-dimensional structuresof proteins on the basis of short (<5 Å) interprotondistance data derived from nuclear Overhauser enhancement (NOE)measurements. The method makes use of Newton's equations ofmotion to increase temporarily the temperature of the systemin order to search for the global minimum region of a targetfunction comprising purely geometric restraints. These consistof interproton distances supplemented by bond lengths, bondangles, planes and soft van der Waals repulsion terms. The latterreplace the dihedral, van der Waals, electrostatic and hydrogen-bondingpotentials of the empirical energy function used in moleculardynamics simulations. The method presented involves the implementationof a number of innovations over our previous restrained moleculardynamics approach [Clore,G.M., Brünger,A.T., Karplus,M.and Gronenborn,A.M. (1986) J. Mol. Biol., 191, 523–551].These include the development of a new effective potential forthe interproton distance restraints whose functional form isdependent on the magnitude of the difference between calculatedand target values, and the design and implementation of robustand fully automatic protocol. The method is tested on threesystems: the model system crambin (46 residues) using X-raystructure derived interproton distance restraints, and potatocarboxypeptidase inhibitor (CPI; 39 residues) and barley serineproteinase inhibitor 2 (BSPI-2; 64 residues) using experimentallyderived interproton distance restraints. Calculations were carriedout starting from the extended strands which had atomic r.m.s.differences of 57, 38 and 33 Å with respect to the crystalstructures of BSPI-2, crambin and CPI respectively. Unbiasedsampling of the conformational space consistent with the restraintswas achieved by varying the random number seed used to assignthe initial velocities. This ensures that the different trajectoriesdiverge during the early stages of the simulations and onlyconverge later as more and more interproton distance restraintsare satisfied. The average backbone atomic r.m.s. differencebetween the converged structures is 2.2 ± 0.3 Åfor crambin (nine structures), 2.4 ± 0.3 Å forCPI (eight structures) and 2.5 ± 0.2 Å for BSPI-2(five structures). The backbone atomic r.m.s. difference betweenthe mean structures derived by averaging the coordinates ofthe converged structures and the corresponding X-ray structuresis 1.2 Å for crambin, 1.6 Å for CPI and 1.7 Åfor BSPI-2.  相似文献   
69.
Extends a study by L. Gannon et al (see record 1992-23274-001) by examining the sex of Ss in American Psychological Association (APA) journals publishing original human studies research and by sampling all APA division journals publishing such research. Two issues of each APA and APA division journal published in 1990 were examined, yielding a sample of 504 articles from 26 journals. 79 cases (9.86%) clearly indicated using Ss of only 1 sex, 440 cases (54.93%) used both male and female Ss and reported sex fully, and 44 cases (5.49%) indicated using Ss of each sex without reporting exact numbers. The evidence suggests that there remains a significant tendency to consider male Ss as "normative," and results obtained from them generally applicable, whereas female Ss are somehow "different," and results obtained from them are specific to female Ss. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
70.
Identification and composition of turnip root lipids   总被引:22,自引:0,他引:22  
Lepage M 《Lipids》1967,2(3):244-250
Two varieties of turnip, Laurentian and Wye, were examined for their lipid and fatty acid composition. Lipids extracted with 80% ethanol contained variable quantities of phosphatidic acid, which was considered to be an artifact. Crude lipids were fractionated by TLC, and fatty acids and sterols were analyzed by GLC. Among the common phospholipids, cardiolipid and phosphatidyl glycerol were abundant components. Linolenic acid comprised 60% of the total fatty acids. β-Sitosterol was the principal sterol, and about half of the carotenoids was lycopene. No great differences between the two varieties studied were observed however. Contribution No. 53 of the Food Research Institute, Canada Department of Agriculture, Ottawa.  相似文献   
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