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21.
A new flushing solution consisting of electrolytes and mannitol has provided successful 3 day canine kidney preservation evidenced by immediate life-supporting renal function. In our experiments the solutions described by Sacks and Collins have failed to achieve this prolonged renal storage but have been successful in storing canine kidneys for 2 days. This relatively simple new hypertonic solution does not require additives and has been successfully used in clinical renal transplantation.  相似文献   
22.
23.
In 1972 the American Board of Pediatrics (ABP) initiated studies leading to a report which identifies the important components of competency needed in the practice of pediatrics. The development of the report involved a group process engaging ABP board members and examiners. The outcome has been (a) the delineation of a process for establishing definitions of competency in a medical discipline; (b) the development of a framework for specifying the abilities needed to perform the tasks required of pediatricians; (c) an elaboration of samples of pediatric subjects to which these abilities and tasks are relevant; and (d) the development of a basis for choice of methods to use for purposes of certification.  相似文献   
24.
Serial cerebral blood flow studies performed by the intra-carotid 133Xenon method were fortuitously determined during the course of a cluster headache in a 32 year old man. The initial study was performed about 10 min after the headache began and showed values at the upper limit of normal. Twenty min after the headache started a second procedure showed that the autoregulatory response on hyperventilation was normal. Ergotamine tartrate was given intra-muscularly 23 min after the headache began and there was partial relief. A third cerebral blood flow estimation showed abnormally high values. The probable reasons for this are discussed.  相似文献   
25.
Eight newly developed pigeonpea genotypes (ICPL 87, ICPL 151, ICPL 270, ICPL 366, ICPL 87051, ICPL 87063, ICPL 87067, and ICPV 1), and the two controls (BDN 2 and C 11) were analysed for cooking quality parameters and chemical composition, including amino acids and minerals. Protein quality was evaluated by determining the true protein digestibility, biological value, net protein utilisation (NPU), and utilisable protein. These genotypes differed significantly (P < 0–01) in the dhal cooking time. Sensory properties of dhal of these genotypes were found to be within the acceptable range, even though there were considerable differences among genotypes. Dhal protein, calcium, magnesium, zinc, and iron contents of these genotypes showed noticeable differences. Calcium content of ICPL 87067 was the highest (85-6 mg per 100 g) and of ICPL 87 the lowest (54-4 mg per 100 g) indicating large differences among the newly developed genotypes. No noticeable differences in sulphur-containing amino acids of these genotypes were observed. NPU was the highest (65–4%) for ICPL 366 and the lowest (56–6%) for ICPL 270 and ICPL 87067 indicating significant (P < 0–01) differences among genotypes studied.  相似文献   
26.
In this paper, we present some new results of our work in a novel polymerization process (called the free-radical retrograde precipitation polymerization, or FRRPP, process) that occurs at temperatures above the lower critical solution temperature. Our polymerization experiments basically involve the methacrylic acid–poly(methacrylic acid)–water system. Experimental results indicate a gradual increase in conversion with time after what seemingly is the onset of phase separation. In an equivalent solution polymerization system, conversion of methacrylic acid reaches almost 100% at a much shorter time than in the FRRPP system. Molecular weights of poly(methacrylic acid) at different times for the FRRPP system are not dramatically different from those obtained in the solution system. However, the FRRPP system yields a relatively narrow molecular weight distribution at a wide range of conversion compared to that obtained in the equivalent solution system. The unique characteristics of the FRRPP process is shown in the asymptotic time behavior of the free-radical concentration compared to the decay behavior in other polymerization systems. © 1996 John Wiley & Sons, Inc.  相似文献   
27.
Zirconium oxide (ZrO2) nanostructures were synthesized by hydrothermal route. Surface morphology analysis depicts the formation of the nanobars and hexagonal-shaped nanodiscs at different synthesis conditions. The structural analysis confirms that the as-synthesized ZrO2 product is of pure monoclinic phase (m-ZrO2) with crystallite size of about 25 nm. The product consists of monodispersed nanoparticles of uniform composition, high purity, and crystallinity. The Raman spectra are quantitatively analyzed and the observed peaks are attributed to various vibration modes of the m-ZrO2. The UV–vis absorption spectrum showed a strong absorption peak at about 292 nm and the estimated optical band gap was around 3.57 eV. Photoluminescence (PL) spectrum of ZrO2 nanostructure showed a strong and broad emission peak at around 410 nm at room temperature, which can be attributed to the ionized oxygen vacancy in the material.  相似文献   
28.
R. S. Verma  S. C. Saxena 《Energy》1983,8(12):909-925
Fluidization and heat transfer experiments have been conducted in gas fluidized beds of two different sizes, viz., 305 × 305 mm2 and 305 × 152.5 mm2 and with particles of silica sands (d?p = 167, 488, 504, and 745 μm), glass beads (dp = 427 μm) and millet seeds (dp = 2064 μm) with immersed smooth vertical heated tubes of diameter 12.7, 28.6, and 50.8 mm. Important conclusions are drawn concerning the dependence of heat transfer coefficient on fluidization velocity, bed particle diameter, tube diameter and nature of bed fluidization. The heat transfer data are employed to assess the available literature correlations for heat transfer coefficient and for its maximum value.  相似文献   
29.
A tubelike, naturally occurring halloysite clay mineral (HNTs) incorporated polyphosphazene (PPZ) elastomeric nanocomposites had been electron beam radiated and thermally treated for certain applications. To improve the dispersion of raw HNTs (H), an organosilane modifier had been exploited. Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD) technique were utilized for plausible interaction and intercalation. The efficiency of electron beam radiation over chemical initiation for intra and inter chain network formation within the resin was substantiated through oil and solvent resistance studies. Effective delay in mass transport as compared to the virgin elastomer was observed through thermal analysis.  相似文献   
30.
The present study was designed to systematically compare the conventional and reverse transfection methodologies for chitosan/DNA complexes using a low molecular weight (MW) chitosan. The hydrodynamic diameter of the complexes, measured by Dynamic Light Scattering (DLS) was found to be ~ 216 nm and TEM investigations showed spherical and compact complexes with an average size of 200 nm. The transfection efficiency of chitosan using the two methodologies was assessed by employing reporter gene coding for green fluorescent protein (GFP) and luciferase. More than 50% of HEK 293 cells were transfected when transfection done using reverse transfection strategy at pH 6.5 with 10% serum for 24 h followed by media replenishment with pH 7.4 with 10% serum for an additional 24 h period. Also, the cytotoxicity of chitosan/DNA complexes was also considerably lower than the commercially available transfection reagent lipofectamine. Our investigation concludes that maximal transgene expression levels could be achieved using reverse transfection where the chitosan/DNA complexes are pre‐incubated on the plate surface followed by plating of cells at pH 6.5 with 10% serum for 24h and media resupplemented with pH 7.4 with 10% serum for an additional 24 h period. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012  相似文献   
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