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951.
The effects of copper and zinc ions on the rate of killing of Gram-negative bacterium Pseudomonas aeruginosa, Gram-positive bacterium Staphylococcus aureus and fungal yeast Candida albicans by antiseptic agents cetylpyridinium chloride and povidone-iodine (Betadine) were investigated. In the 48 test cases copper and zinc ions clearly potentiated the antiseptic agents in 28 (58.3%) cases and exhibited an improved (not clear potentiation) activity in 15 (31.3%) cases. In five (10.4%) cases there was no change in the antiseptics' antimicrobial activity. In general zinc potentiated the antiseptic agents more than copper. If an 'improved activity' was the only criterion for this study, then a more rapid antimicrobial effect was observed in 43 out of the 48 test cases, i.e., 90%. 相似文献
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We have treated eight cases of childhood ingestion of alkaline disk batteries, one resulting in an esophagotracheal fistula. These batteries are capable of rapid tissue destruction on contact with moist membranes. We recommend that packaging include proper warning of this hazard and urge that retained batteries be promptly removed from the esophagus and stomach by endoscopy or laparotomy. If the battery has reached the small intestine, further transit should be monitored carefully by roentgenographic studies until recovery. Perforation is possible after eight-hour retention at a specific site. 相似文献
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PL Ornstein TJ Bleisch MB Arnold JH Kennedy RA Wright BG Johnson JP Tizzano DR Helton MJ Kallman DD Schoepp M Hérin 《Canadian Metallurgical Quarterly》1998,41(3):358-378
In this paper we describe the synthesis of a series of alpha-substituted analogues of the potent and selective group II metabotropic glutamate receptor (mGluR) agonist (1S,1'S,2'S)-carboxycyclopropylglycine (2, L-CCG 1). Incorporation of a substitutent on the amino acid carbon converted the agonist 2 into an antagonist. All of the compounds were prepared and tested as a series of four isomers, i.e., two racemic diastereomers. On the basis of the improvement in affinity realized for the alpha-phenylethyl analogue 3, in this paper we explored the effects of substitution on the aromatic ring as a strategy to increase the affinity to these compounds for group II mGluRs. Affinity for group II mGluRs was measured using [3H]glutamic acid (Glu) binding in rat forebrain membranes. Antagonist activity was confirmed for these compounds by measuring their ability to antagonize (1S,3R)-1-aminocyclopentane-1,3-dicarboxylic acid-induced inhibition of forskolin stimulated cyclic-AMP in RGT cells transfected with human mGluR2 and mGluR3. Meta substitution on the aromatic ring of 3 with a variety of substituents, both electron donating (e.g., methyl, hydroxy, amino, methoxy, phenyl, phenoxy) and electron withdrawing (e.g., fluorine, chlorine, bromine, carboxy, trifluoromethyl) gave from 1.5- to 4.5-fold increases in affinity. Substitution with p-fluorine, as in 97 (IC50 = 0.022 +/- 0.002), was the exception. Here, a greater increase in affinity was realized than for either the ortho- or meta-substituted analogues; 97 was the most potent compound resulting from monosubstitution of the aromatic. At best, only modest increases in affinity were realized for certain compounds bearing either two chlorines or two fluorines, and two methoxy groups gave no improvement in affinity (all examined in a variety of substitution patterns). Three amino acids, 4, 5, and 104, were resolved into their four constituent isomers, and affinity and functional activity for group II mGluRs was found to reside solely in the S,S,S-isomers of each, consistent with 1. With an IC50 = 2.9 +/- 0.6 nM, the resolved xanthylmethyl compound 168 was the most potent compound from this SAR. Amino acid 168 demonstrated high plasma levels following intraperitoneal (i.p.) administration and readily penetrated into the brain. This compound, however, had only limited (approximately 5%) oral bioavailability. Systemic administration of 168 protected mice from limbic seizures produced by the mGluR agonist 3,5-dihydroxyphenylglycine, with an ED50 = 31 mg/kg (i.p., 60 min preinjection). Thus, 168 represents a valuable tool to study the role of group II mGluRs in disease. 相似文献
957.
JS Valentine DL Wertz TJ Lyons LL Liou JJ Goto EB Gralla 《Canadian Metallurgical Quarterly》1998,2(2):253-262
The aim of this study was to evaluate the clinical function and long-term prognosis of overdentures retained by a small number of implants in the maxilla and mandible using one of two different attachment systems. Included in the study were all patients referred to specialty clinics in J?nk?ping and Link?ping, Sweden, during the treatment period who needed an overdenture and could be provided with a minimum number of two bilaterally-placed implants. Excluded were patients with bone-grafted jaws, irradiated cancer patients, heavy bruxers, and patients who had lost a fixed prosthesis because of implant losses. The patients were randomly assigned to receive one retentive system, either a round 2-mm-diameter bar with clips or ball attachments (Nobel Biocare). Eighteen overdentures were placed in maxillae and 32 in mandibles, supported by a total of 115 Br?nemark implants. Of the implants placed, 86.1% were continuously osseointegrated. The cumulative implant survival rates after 7 years of loading were 75.4% in the maxillae and 100% in the mandibles. There was no difference in implant survival rate between the attachment systems. Patients with implant losses were characterized by severely resorbed maxillary ridges and inferior bone quality, together with unfavorable loading circumstances such as short implants combined with long leverages. Complications and prosthetic adjustments were mostly resolved early and easily. 相似文献
958.
G van Zandbergen C van Kooten NK Mohamad TJ Reterink JW de Fijter JG van de Winkel MR Daha 《Canadian Metallurgical Quarterly》1998,13(12):3058-3064
BACKGROUND: Primary IgA nephropathy (IgAN) is associated with elevated levels of circulating IgA and is characterized by deposition of primarily IgA1 in the renal mesangium. It has not yet been clarified which mechanisms govern the deposition of IgA1 in the mesangium. One of the factors which may play a role in trapping of IgA in the mesangial area is the interaction of IgA with specific IgA receptors (Fc alphaR, CD89) on the mesangial cells. METHODS: In the present study IgA derived from patients with IgAN and controls was investigated for its interaction with human CD89, expressed on the surface of the murine B cell line IIA1.6. RESULTS: IgA binding to CD89 expressing cells was specific, concentration dependent and binding of dIgA and pIgA occurred in a more efficient fashion than that of mIgA. IgA binding to CD89 directly from serum of patients compared to controls showed no significant difference. However these experiments are affected by differences in IgA concentration and combinations of different sizes of IgA. Using purified fractions of mIgA, dIgA, and pIgA isolated from serum, a significantly reduced binding of mIgA to CD89 from patients compared to controls was observed. Finally, the binding of aIgA2 to CD89 was less inhibited using mIgA from patients with IgAN compared to controls. CONCLUSIONS: The reduced binding of mIgA to CD89 seems to contradict a direct role for CD89 in deposition of IgA. However reduced binding of mIgA to CD89 may affect IgA clearance, leading to higher serum IgA. Furthermore, since it has been demonstrated that mIgA can interfere with binding of di- and pIgA, CD89 could still contribute to pIgA deposition in the mesangial area. 相似文献
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960.
This paper identifies the improvements due to large-scale integration [LSI] in the areas of cost, performance, size, reliability, and testing of data communication equipments. An example using Motorola's MC6860 Digital Modem is given. Techniques for implementing linear functions using digital designs and processing methods are discussed along with future technology trends and projections. 相似文献