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1.
An autopsy case of retroperitoneal leiomyosarcoma of a centenarial male is described. He complained of abdominal pain in his left side 1 month before his death. Ultrasonography and computed tomography revealed a large mass in the left abdominal cavity. At autopsy, a circumscribed mass, 15 cm in diameter, was found in the left-upper abdominal cavity, and seemed to be derived from the retroperitoneum in an exophytic manner. Histologically, spindle cells with slight eosinophilic cytoplasm and blunt-ended nuclei showed interwoven fascicular growth, and mitotic figures were easily encountered. Immunohistochemically, the tumor cells were labeled by alpha-smooth muscle actin and vimentin. To our knowledge, this case of leiomyosarcoma has presented in the oldest patient ever reported. The rarity of soft tissue sarcomas in the extremely elderly is also discussed.  相似文献   
2.
Varying the formulation and processing conditions of polymer blends allows the design of materials with a large range of morphologies. Active materials embedding active compounds in a devoted phase are promising applications of such blends, offering possible various transport properties. In this study, 13 poly(butylene succinate‐co‐butylene adipate) (PBSA)/polyethylene oxide (PEO) blends were extruded in a slit die. Their morphologies were characterized by water extraction (selective PEO dissolution), FTIR spectroscopy, and differential scanning calorimetry. Transport properties were assessed by water vapor permeation and fluorescein release as model migrant. Indeed, the desorption in water of fluorescein (previously entrapped in PEO) was monitored to preliminary investigate the release properties of these materials: two morphologies were obtained (i) pseudo multilayer films made of PEO‐rich layer/PBSA‐rich layer/PEO‐rich layer and (ii) PEO nodules dispersed in the PBSA‐rich matrix for the highest PBSA contents. The first systems were erodible ones with an uncontrolled fast delivery by PEO dissolution whereas the second ones showed a controlled release by permeation through the PBSA matrix from PEO nodules. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 42874.  相似文献   
3.
The release of drugs and their metabolites into the environment is of a great concern, as far as the water pollution is concerned. One can cite oxytetracycline which is used in large quantities and it is essential to reduce its presence in aquatic environments.  相似文献   
4.
Spatial scales and methods for dealing with scale have been widely discussed in the water resources literature. Different spatial processes operate at different scales so interpretations based on data from one scale may not apply to another. Understanding the behavior of phenomena at multiple-scales of data aggregation is thus imperative to accurate integrations of data and models at different geographic resolutions. This study tests theoretical concepts of scale by presenting empirical results of multiscale GIS and statistical analyses on gridded water-availability, water use and population data for the Danube Basin in Europe, with results corroborated by similar tests in the Ganges (South Asia) and Missouri (North America) Basins. Fine-resolution datasets were aggregated to coarser grid sizes and standard statistical measures of spatial variability were computed. Statistical analysis of spatial variability demonstrated two distinctly different cases for unscaled and scaled variables. Results show that variance (and standard deviation) in unscaled variables like freshwater supply, use and population increases at coarser scales—contrary to the common assumption of decreasing variability as grid-cell size increases. On the other hand, a decreasing trend in variability with scale is noted for variables scaled to area or population (like population density, water availability per capita etc.). Moreover, relationships between variability and scale show strong non-linear trends. No mention of these relationships has been found in the water resources or socio-economic literature for scale and variability. Regression analyses suggest that power functions are the most appropriate model to fit trends in increasing variability at multiple scales. These results can be applied to interpretations of water-stress and water scarcity data and their locations relative to water sources or topographic barriers.  相似文献   
5.
The RecQ-related family of DNA helicases is required for the maintenance of genomic stability in organisms ranging from bacteria to humans. In humans, mutation of three RecQ-related helicases, BLM, WRN and RecQL4, cause the cancer-prone and premature ageing diseases of Bloom syndrome, Werner's syndrome and Rothmund-Thompson syndrome, respectively. In the fission yeast Schizosaccharomyces pombe, disruption of the rqh1(+) gene, which encodes the single Sz. pombe RecQ-related helicase, causes cells to display reduced viability and elevated levels of chromosome loss. After S-phase arrest or DNA damage, cells lacking rqh1(+) function display elevated levels of homologous recombination and defective chromosome segregation. Here we show that, like other RecQ family members, the Rqh1p protein displays 3' to 5' DNA helicase activity. Interestingly, however, unlike other RecQ family members, the helicase activity of Rqh1p is only partially required for its function in recovery from S-phase arrest or DNA damage. We also report that high cellular levels of Rqh1p result in lethal chromosome segregation defects, while more moderate levels of Rqh1p cause significantly elevated rates of chromosome loss. This suggests that careful regulation of RecQ-like protein levels in eukaryotic cells is vital for maintaining genome stability.  相似文献   
6.
Thermostable enzymes are currently being investigated to improve industrial processes of starch saccharification. A novel glucoamylase was purified to electrophoretic homogeneity from the culture supernatant of Fusarium solani on a fast protein liquid chromatographic system (FPLC). The recovery of glucoamylase after gel filtration on FPLC was 31.8% with 26.2-fold increase in specific activity. The enzyme had a molecular mass of 40 kDa by SDS-PAGE and 41 kDa by gel filtration. The glucoamylase exhibited optimum activity at pH 4.5. The Kcat and Km were 441/min and 1.9 mg/ml, respectively, for soluble starch, specificity constant (Kcat/Km) was 232. The enzyme was thermally stable at 50 °C and retained 79% activity after 60 min at this temperature. The half-life of the enzyme was 26 min at 60°C. The enzyme was slightly stimulated by Cu2+ and Mg2+ and strongly inhibited by Hg2+, Pb2+, Zn2+, Ni2+ and Fe3+.  相似文献   
7.
The waste distillery sludge from sugar-cane industry was pretreated physically (boiled, heated and autoclaved) as well as chemically (HCl, H(2)SO(4), H(3)PO(4), NaOH, Ca(OH)(2), Al(OH)(3), C(6)H(6), HCHO, CH(3)OH and C1(2)H(25)OSO(3)Na (sodium dodecyl sulphate (SDS)) for assessing the comparative sorption capacity of untreated and modified distillery sludge for Pb(II) biosorption from aqueous solutions. Experiments were conducted in shake flasks on a batch basis to access the effect of different experimental parameters such as pH, biosorbent dosage, biosorbent size, initial Pb(II) concentration and contact time. The uptake capacity 'q' (mg/g) of untreated and pretreated distillery sludge was in following order: NaOH (51.29+/-1.21)>HCl (49.82+/-1.22)>HCHO (49.56+/-1.14)>H(2)SO(4) (47.71+/-1.20)>HgCl(2) (45.32+/-1.06)>Ca(OH)(2) (44.01+/-1.18)>MeOH (43.73+/-1.23)>C(6)H(6) (42.72+/-1.19)>H(3)PO(4) (42.01+/-1.17)>SDS (40.87+/-1.27)>autoclaved (40.23+/-1.24)>Boiled (39.95+/-1.19)>heated (38.87+/-1.32)>Al (OH)(3) (38.30+/-1.14)>untreated (37.76+/-1.21). In further parameter studies, the optimized biosorbent size was 0.250 mm at pH 5 and best dose was 0.05 g of biosorbent. The applicability of the Langmuir and Freundlich models for sorption process was tested and best fitted model was Langmuir with the coefficient of determination (R(2)) value, 0.97, the process followed second order kinetic mechanism.  相似文献   
8.
With the demand for microstructures of not only with diversified shape but also of reduced dimension on glass, fabrication of polycrystalline diamond (PCD) tool/microelectrodes with different shape has become important. However, to date, fabrication of different shapes in single setup is not possible and also needs special indexing attachment. To solve this problem, in this study, a specially designed block containing three v-slots of 60°, 90°, and 120° has been designed and fabricated using wire cut. Thereafter with the help of block electro-discharge machining method and using this specially designed block, different shapes of microelectrodes with symmetrical and non-symmetrical section has been fabricated. This study also investigates the feasibility of using these different geometry PCD tool for micro-grinding of BK7 glass. In this context, a relative study on the micro-grinding performance of four different geometry tools (circular, D-shaped, triangular, and square) has been carried out. It has been observed that among the different shaped tools, D-shaped tool experienced lowest cutting force along x- and y-axes where as triangular tool faced lowest force along z-axis, and highest cutting forces were found to be experienced by square tool. Average and maximum roughness of machined surface was found to be improved from circular to others tool except triangular one. But, it was also observed that side surface started to deteriorate from circular to other tool due to edge wear. In case of tool wear, square and triangular tool experienced more wear than circular and D-shaped tool due to their frequent edge blunting or rounding effect. Finally, among four different geometry tools, D-shaped tool was considered to provide better performance in terms of the achieved surface finish, tool wear, and cutting force analysis.  相似文献   
9.
10.
This study was carried out to appraise whether or not the exogenous application of a potential osmoprotectant, proline, could ameliorate the adverse effects of drought stress on maize seed and seed oil composition, as well as oil antioxidant activity. Water stress reduced the kernel sugar, oil, protein and moisture contents and most of the seed macro- and micro-elements analyzed in both maize cultivars but it increased the contents of seed fiber and ash. Water stress increased the oil oleic acid content with a subsequent decrease in the amount of linoleic acid, resulting in an increased oil oleic/linoleic ratio for both maize cultivars. However, no variation was observed in oil stearic and palmitic acids content due to water stress. A considerable drought induced an increase in seed oil α-, γ-, δ- and total tocopherols and flavonoids were observed in both maize cultivars. However, oil phenolic and carotenoid content as well as 1,1-diphenyl-2-picryl-hydrazyl (DPPH) free radical scavenging activity decreased. Foliar-applied proline significantly increased the content of seed sugar, oil, protein, moisture, fiber and ash in both maize cultivars under well irrigated and water deficit conditions. Furthermore, exogenous application of proline increased the oil oleic and linoleic acid contents. The concentrations of antioxidant compounds namely phenolics, carotenoids, flavonoids and tocopherols estimated in the seed oil increased due to foliar-applied proline under water deficit conditions that was positively correlated with the enhanced oil DPPH free radical scavenging activity. Moreover, the increase in the contents of these antioxidant compounds and oil antioxidant activity due to the foliar application of proline was noted to be more pronounced under water deficit conditions.  相似文献   
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