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51.
We investigated the stability of the secondary amines, desipramine (DP) and nortriptyline (NRT), and the tertiary amines, imipramine (IP) and amitriptyline (AT), in formaldehyde (F) and paraformaldehyde (PF) aqueous solutions. NRT showed little instability in 0.37 to 37% F and PF solutions, but AT formation was detected and increased, up to 0.46 to 2.7%, in parallel with rising F and PF concentrations. DP was unstable and levels decreased to 74 to 96% with increasing F concentrations, and fell only to 96% in 10% PF solution. IP formation increased in the same manner as AT to 2.9 to 3.5% of the initial DP. When AT and IP were stored in F and PF solutions, concentrations of AT and IP did not change. DP in F pH 3 to 11 phosphate buffer (PB) solutions showed high recovery in the order: pH 5 > pH 7 > pH 9 > pH 3 and pH 11. DP in PF buffered solutions decreased slightly only at pH 3 (3.5%). By contrast, IP did not change at any pH (pH 3 to 11) of the F or PF solutions. During storage for 21 days at room temperature in 3.7% F and PF solutions, IP and DP degradation was accelerated when compared with the values in pH 3 and 7 PB solutions. However, IP detected in DP F or PF solution was only 0.2% of the initial DP 21 days after storage. Thus, AT, NRT, IP and DP degraded gradually in F and PF solutions during storage at room temperature. TCAs may first react nucleophilically with formaldehyde to form hemiaminals. DP in 3.7% formaldehyde aqueous solution formed little of its methylated product, IP, at room temperature.  相似文献   
52.
The deposition of particles on millimeter-sized single spheres in transverse high gradient magnetic separation (HGMS) is observed microscopically under different conditions of magnetic field and flow velocity. The results are related to a semiempirical model of the collection process as a function of total particle mass transfer through the system.  相似文献   
53.
The electronics fields face serious problems associated with electric power; these include the development of ecologically friendly power-generation systems and ultralow-power-consuming circuits. Moreover, there is a demand for developing new power-transmission methods in the imminent era of ambient electronics, in which a multitude of electronic devices such as sensor networks will be used in our daily life to enhance security, safety and convenience. We constructed a sheet-type wireless power-transmission system by using state-of-the-art printing technologies using advanced electronic functional inks. This became possible owing to recent progress in organic semiconductor technologies; the diversity of chemical syntheses and processes on organic materials has led to a new class of organic semiconductors, dielectric layers and metals with excellent electronic functionalities. The new system directly drives electronic devices by transmitting power of the order of tens of watts without connectors, thereby providing an easy-to-use and reliable power source. As all of the components are manufactured on plastic films, it is easy to place the wireless power-transmission sheet over desks, floors, walls and any other location imaginable.  相似文献   
54.
Many biomaterials have been evaluated using cultured cells. In particular, osteoblast-like cells are often used to evaluate the osteocompatibility, hard-tissue-regeneration, osteoconductive, and osteoinductive characteristics of biomaterials. However, the evaluation of biomaterial osteogenesis-inducing capacity using osteoblast-like cells is not standardized; instead, it is performed under laboratory-specific culture conditions with different culture media. However, the effect of different media conditions on bone formation has not been investigated. Here, we aimed to evaluate the osteogenesis of MC3T3-E1 cells, one of the most commonly used osteoblast-like cell lines for osteogenesis evaluation, and assayed cell proliferation, alkaline phosphatase activity, expression of osteoblast markers, and calcification under varying culture media conditions. Furthermore, the various media conditions were tested in uncoated plates and plates coated with collagen type I and poly-L-lysine, highly biocompatible molecules commonly used as pseudobiomaterials. We found that the type of base medium, the presence or absence of vitamin C, and the freshness of the medium may affect biomaterial regeneration. We posit that an in vitro model that recapitulates in vivo bone formation should be established before evaluating biomaterials.  相似文献   
55.
BACKGROUND/AIMS: This study was conducted to clarify the effect of percutaneous ethanol injection (PEI) in combination with transcatheter arterial embolization (TAE) on prolonging the survival time of patients with postoperative recurrence of hepatocellular carcinoma (HCC). MATERIALS AND METHODS: The subjects were 97 consecutive patients (pts) treated for postoperative recurrent HCC between February 1987 and March 1993. Of these, 25 pts received both TAE and PEI and 72 pts received TAE alone. In the TAE & PEI group, treatment was selected according to the indications: 15 pts received TAE for multiple recurrences following PEI, and the other 10 pts received PEI for a new or residual lesion following TAE. Fourteen demographic, pathological, and clinical variables were evaluated to estimate the relative risk of pts treated with TAE & PEI or with TAE alone. RESULTS: The 1-, 3- and 5- year survival rates in the TAE & PEI group were 100%, 73.2% and 27.2%, respectively, and those in the TAE alone group were 88.9%, 30.2% and 5.5%, respectively. Based on multi-variate Cox regression analysis, the relative risk of cancer death in the TAE & PEI group was 0.32 (95% confidence interval, 0.15 to 0.67). CONCLUSION: The combination of TAE and PEI had a positive palliative effect and increased survival time of patients with postoperative recurrent HCC, compared to results obtained by TAE alone.  相似文献   
56.
The REMEDi HS is a broad spectrum drug identification system, designed for emergency toxicology screening and forensic applications. The total analysis time is about 20 min. The current library has 555 drugs and metabolites. The system has a software routine that uses an internal standard (IS) to perform quantitative analysis for target compounds when calibrators are available; further, response factors (RF) are supplied for a rapid estimate of drug concentrations when calibrators are unavailable. In the present study, The concentrations of six drugs (bromisovalum, ephedrine, hydroxyzine, diphenhydramine, ranitidine, and lidocaine) and a metabolite of lidocaine (glycinexylidide) were determined using both methods. The slopes of the regression lines between the rapid estimate method and the IS method were generally within 20% of unity, in agreement with the manufacturer's claim. Semiquantitative estimates based on RF also showed good agreement with results obtained using multipoint calibration. These estimates were sufficient for clinical differentiation of routine and toxic levels. Our study demonstrated that the REMEDi HS is particularly useful for a rapid estimate of drug concentrations in the samples from emergency cases when calibrators are not readily available. Our study also showed that this system can be used for the therapeutic monitoring of ranitidine, bromisovalum, lidocaine, and diphenhydrmine.  相似文献   
57.
58.
Palliative care was initiated in Italy towards the end of the 1970s, mainly through the efforts of Professor Ventafridda and his colleagues. This article describes some of the most important steps made in this country to gain widespread acceptance for the principles and practice of palliative care. After about 15 years the Italian situation is still confusing. While some Regions have made progress, others are far from reaching even minimal goals. The efforts of many charities and of the Italian Society for Palliative Care and the Italian School for Palliative Medicine, have been huge, but still not sufficient to promote widespread involvement of the National Health Authorities. In the absence of clear Regional and central laws, the recent changes in the Italian health system combined with increasing financial difficulties threaten the advances already made.  相似文献   
59.
The effect of interleukin-1 beta (IL-1 beta) on a cerebral artery was investigated in anesthetized dogs. Intracisternal administration of IL-1 beta (0.03 and 0.3 micrograms) dilated the canine basilar artery in a dose-dependent manner, without affecting systemic blood pressure or heart rate. The increase in diameter induced by 0.3 micrograms of IL-1 beta was 28.4% +/- 13.4% of control at 2 hours and was inhibited by 30 micrograms of the IL-1 beta receptor antagonist, zinc protoporphyrin (4.5% +/- 13.5%, P < 0.05). Interleukin-1 beta did not affect the concentration of nitric oxide metabolites in CSF. However, there was an increase in the concentration of eicosanoids in CSF, and the elevation of 6-keto-PGF1 alpha paralleled the vasodilation. Pretreatment with 30 micrograms of the selective inducible cyclooxygenase (COX-2) inhibitor NS-398 also inhibited the IL-1 beta-induced vasodilation significantly (5.9% +/- 9.4% at 2 hours, P < 0.01). Western blot analysis revealed the expression of a 68-kD COX-2-like protein in basilar artery extracts. These findings suggest that the IL-1 beta-induced vasodilator effect is linked to the prostaglandin cascade, predominantly to prostaglandin I2, by induction of COX-2, but not to the stimulation of nitric oxide metabolism.  相似文献   
60.
How to improve mechanical properties of polylactic acid with bamboo fibers   总被引:1,自引:0,他引:1  
Bamboo fibers (BF) were mixed in polylactic acid (PLA) to improve its mechanical properties: impact strength and heat resistance. Three different types of BF were extracted from raw bamboo by either sodium hydroxide (NaOH) treatment or steam explosion in conjunction with mechanical processing. They were designated as “short fiber bundle,” “alkali-treated filament” and “steam-exploded filament,” respectively. Composite samples were fabricated by injection molding using PLA/BF pellets prepared by a twin-screw extruding machine. Among them, the highest bending strength was obtained when steam-exploded filaments were put into PLA matrix. Impact strength of PLA was not greatly improved by addition of short fiber bundles as well as both filaments. In order to improve the impact strength of PLA/BF composites, PLA composite samples were alternatively fabricated by hot pressing using medium length bamboo fiber bundles (MFB) to avoid the decrease in fiber length at fabrication. Impact strength of PLA/MFB composite significantly increased, in which long fiber bundles were pulled out from the matrix. The addition of BF improves thermal properties and heat resistance of PLA/BF composites due to the constraint of deformation of PLA in conjunction with crystallinity promoted by anneal (at 110 °C for 5 h).  相似文献   
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