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1.
The availability of an analgesic compound devoid of the side effects associated with the commonly used opioid and nonsteroidal antiinflammatory drugs would be useful during the perioperative period. Although adenosine has analgesic and anesthetic-sparing properties, it also produces dose-dependent cardiovascular depression. Inhibitors of adenosine kinase may be able to provide analgesia without producing acute cardiovascular or respiratory depression. This preliminary study investigated the effects of a novel adenosine kinase-inhibiting drug, GP683, on the minimum alveolar anesthetic concentration (MAC) of desflurane in dogs. Seven mongrel dogs were administered one of three different GP683 dose regimens (or the solvent) by intravenous infusion on separate occasions according to a cross-over study design. After determining the baseline desflurane MAC value, GP683 was infused at 75, 150, or 300 microg x kg(-1) x min(-1) for 5 min as a loading dose, followed by 15, 30, or 60 microg x kg(-1) x min(-1) for an additional 85 min to maintain a stable plasma drug level. The desflurane MAC was redetermined 30-90 min after starting the study drug or vehicle infusion, and 30-90 min and 120-180 min after termination of the infusion. Cardiovascular variables and plasma concentrations of GP683 were determined at specific intervals before, during, and after the MAC determinations. The three GP683 dose regimens produced 22%, 31%, and 50% decreases in the desflurane MAC, respectively. In addition, there was good correlation between the decrease in desflurane MAC and the plasma GP683 concentration (r = -0.78). Although the mean arterial pressure (MAP) was decreased up to 25% by the highest infusion rate of GP683, adjustments in the desflurane concentration to an equi-MAC value resulted in normalization of the MAP values. Furthermore, GP683 produced no changes in heart rate. In conclusion, the adenosine kinase-inhibiting drug, GP683, produced dose-dependent decreases in the desflurane MAC of dogs without producing untoward hemodynamic changes. IMPLICATIONS: An investigational drug (GP683) that can increase the levels of an important endogenous substance in the body (adenosine) has been found to decrease the anesthetic requirement in dogs without producing adverse effects on the cardiovascular system.  相似文献   
2.
This article presents rapid, sensitive, direct detection of Salmonella Typhimurium on eggshells by using wireless magnetoelastic (ME) biosensors. The biosensor consists of a freestanding, strip-shaped ME resonator as the signal transducer and the E2 phage as the biomolecular recognition element that selectively binds with Salmonella Typhimurium. This ME biosensor is a type of mass-sensitive biosensor that can be wirelessly actuated into mechanical resonance by an externally applied timevarying magnetic field. When the biosensor binds with Salmonella Typhimurium, the mass of the sensor increases, resulting in a decrease in the sensor's resonant frequency. Multiple E2 phage-coated biosensors (measurement sensors) were placed on eggshells spiked with Salmonella Typhimurium of various concentrations (1.6 to 1.6 × 10(7) CFU/cm(2)). Control sensors without phage were also used to compensate for environmental effects and nonspecific binding. After 20 min in a humidity-controlled chamber (95%) to allow binding of the bacteria to the sensors to occur, the resonant frequency of the sensors was wirelessly measured and compared with their initial resonant frequency. The resonant frequency change of the measurement sensors was found to be statistically different from that of the control sensors down to 1.6 × 10(2) CFU/cm(2), the detection limit for this work. In addition, scanning electron microscopy imaging verified that the measured resonant frequency changes were directly related to the number of bound cells on the sensor surface. The total assay time of the presented methodology was approximately 30 min, facilitating rapid detection of Salmonella Typhimurium without any preceding sampling procedures.  相似文献   
3.
A phase-change optical disc was observed using a reflection-mode scattering-type scanning near-field optical microscope (RS-SNOM). In an a.c.-mode SNOM image, the 1.2 microm x 0.6 microm recording marks were successfully observed although the data were recorded on the groove. In contrast, no recording marks could be resolved in a d.c.-mode SNOM image. These results are in good agreement with those from a numerical simulation using the finite difference time domain method. The resolution was better than 100 nm with a.c.-mode SNOM operation and the results indicate that recording marks in phase-change optical media can be directly observed with the RS-SNOM.  相似文献   
4.
Wind flows over the 8.2-m Subaru Telescope at Mauna Kea in Hawaii were analyzed with a correlation method. Three or four wind flows were detected from our measurements. Spatial and temporal resolution of the wind-flow analysis across the 8.2 m pupil were investigated experimentally. A three-dimensional spatiotemporal-frequency analysis was also applied to the wind-flow data.  相似文献   
5.
We determine the pH dependency of the mid-infrared spectra in aqueous solution of the organic dissociative materials in the metabolic pathway: saccharide phosphates (G6P, F6P), adenosine, and its phosphates (ATP, ADP, AMP). The series of molar absorbance spectra for these reagents were obtained in a pH range of about 2 to 11 with a Fourier transform infrared (FT-IR) spectrometer equipped with a horizontal diamond attenuated total reflection (ATR) sampling accessory. We also provide a method of infrared spectral extraction of ionic dissociative materials by performing a linear least-square fitting utilizing the formulas of ionic dissociation equilibrium shift, and we obtain the infrared spectrum of each ionic species of the dissociative materials: G6P-, G6P2-; F6P-, F6P2-; ATP2-, ATP3-, ATP4-; ADP-, ADP2-, ADP3-; AMP, AMP-, AMP2-; and adenosine+, adenosine0. The infrared spectral structure of each ionic species of the dissociative materials in the metabolic pathway are discussed. Additionally, the possibility for a quantification system of the concentrations of the organic dissociative materials in varying pH is suggested.  相似文献   
6.
This article describes 2 white male patients with probable splenic crisis caused by sickle cell trait after travel from sea level to a moderately high altitude. Both did well with return to lower altitude and conservative treatment. Although rare, this entity should be considered in patients presenting to the emergency department with left-sided chest or abdominal pain after travel to moderate or high altitude.  相似文献   
7.
Poly(L ‐lactic acid) (PLLA), poly(ε‐caprolactone) (PCL), and their films without or blended with 50 wt% poly(ethylene glycol) (PEG) were prepared by solution casting. Porous films were obtained by water‐extraction of PEG from solution‐cast phase‐separated PLLA‐blend‐PCL‐blend‐PEG films. The effects of PLLA/PCL ratio on the morphology of the porous films and the effects of PLLA/PCL ratio and pores on the physical properties and biodegradability of the films were investigated. The pore size of the blend films decreased with increasing PLLA/PCL ratio. Polymer blending and pore formation gave biodegradable PLLA‐blend‐PCL materials with a wide variety of tensile properties with Young's modulus in the range of 0.07–1.4 GPa and elongation at break in the range 3–380%. Pore formation markedly increased the PLLA crystallinity of porous films, except for low PLLA/PCL ratio. Polymer blending as well as pore formation enhanced the enzymatic degradation of biodegradable polyester blends. Copyright © 2006 Society of Chemical Industry  相似文献   
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9.
Owing to the corrosive conditions in coastal areas, aluminium alloy railings and similar structures are normally used on infrastructure works such as bridges and roads located in such areas because aluminium alloys are inherently corrosion resistant. However, to achieve rigid support, aluminium alloy members are often embedded in concrete. Consequently, the embedded parts undergo corrosion caused by the alkaline content of the cement used in the concrete. This research was carried out to study the corrosion behaviour on both the embedded and unembedded sides of aluminium alloy A6061-T6 members embedded in the concrete and also to investigate the ability of a combined coating of anodic oxide and organic film to inhibit corrosion. Additionally, the influence of scratch damage on the performance of this coating material was evaluated.  相似文献   
10.
One thousand two hundred cycles of accelerated exposure experiment with combined salt water spray simulating atmospheric corrosion was performed for investigating the effect of weld line direction and paint orientation on the corrosion and paint deterioration characteristics of welded part of the steel. The corrosion depth of the weld toe of transverse weld line became 1.35 times as large as that of the base metal part because of the remained salt water on the weld toe. The coating thickness at the weld toe became thin by vertically painting on the transverse weld line. When the scribe line was installed at the thin painted weld toe under the transverse weld line, the paint blister area became 15% larger than that of the base metal part. The paint coating thickness at the weld toe in different weld line directions and paint orientations should be confirmed and ensured from the viewpoints of manufacturing and maintaining steel structures.  相似文献   
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