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861.
The effect of complexes of lidocaine with zinc, copper and cobalt on histamine release from peritoneal rat mast cells induced by various secretagogues was investigated. The complexes of lidocaine with metal ions inhibited histamine release induced by compound 48/80 and ionophoreous antibiotics: A23187 and X537A. The ionic complex of lidocaine with zinc was found to be the most potent against 48/80--induced histamine release and exerted the significant inhibition in the concentration of 10(-5) M. The action of coordination complex of lidocaine with zinc was somewhat weaker. The significant inhibitory effect on 48/80-induced histamine release of the copper and cobalt lidocaine complexes was observed in concentration of 10(-4) M. Histamine release by ionophores A23187 and X537A was also affected by zinc lidocaine complexes. However, coordination complex had more potent action on histamine release than the ionic one.  相似文献   
862.
The main goal of this study was to offer data about the efficacy of virtual reality exposure (VRE) in the treatment of panic disorder with or without agoraphobia (PDA). The study was a between‐subject design with three experimental conditions (VRE group, in vivo exposure [IVE] group and waiting‐list [WL] group) and repeated measures (pre‐treatment, post treatment and 12 month follow‐up). The treatment programmes lasted 9 weekly sessions. Thirty‐seven patients meeting DSM‐IV criteria for PDA participated in this study. The improvement achieved using virtual exposure was superior to a WL condition and similar to that achieved using IVE. Our results support the efficacy of VRE in the treatment of PDA at short and long term. The advantages of VRE for the treatment of PDA regarding cost‐benefit issues are described. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   
863.
Although nosocomial pneumonia in non-ventilated patients continues to be frequent and have high mortality rates, knowledge of the associated risk and prognostic factors is still limited. This retrospective study was designed to analyze epidemiological characteristics, risk and prognostic factors in patients with nosocomial pneumonia admitted to a hospital internal medicine department. Data on epidemiological, clinical and microbiological factors as well as diagnosis and clinical course were obtained from the medical records of 104 patients diagnosed with nosocomial pneumonia, according to Centers for Disease Control criteria, and from 104 control subjects. The incidence of nosocomial pneumonia was 18.8 per 1000 admissions. Risk factors significantly associated with contracting the disease were female sex, hospital stay longer than 14 days, other admission in the previous month and use of antibiotics during the previous six weeks. The most frequent underlying diseases were cardiorespiratory in nature (59.4 %). Prognostic factors significantly associated with increased mortality were serious underlying disease, initially critical clinical status, severe and moderate respiratory insufficiency and bilateral radiological signs. More epidemiological data are needed to improve the diagnosis, treatment and prevention of nosocomial pneumonia.  相似文献   
864.
 In this prospective study, the risk factors associated with nosocomial sepsis Caused by Acinetobacter baumannii or Pseudomonas aeruginosa were compared. Prior use of broad-spectrum antibiotics, urinary tract catheter, prior surgery, and mechanical ventilation were significantly associated with nosocomial sepsis caused by Acinetobacter baumannii. The mean prognostic factors significantly associated with mortality were known focus of infection, multiresistant Acinetobacter baumannii, and inappropriate antibiotic treatment. Adequate knowledge of these findings is important to ensure appropriate management of patients and rational use of antibiotics.  相似文献   
865.
The fretting corrosion of five materials for implant suprastructures (cast-titanium, machined-titanium, gold alloy, silver-palladium alloy and chromium-nickel alloy), was investigated in vitro, the materials being galvanically coupled to a titanium ball-and-socket-joint with tetrafluoroethylene under mechanical load. Various electrochemical parameters (E(corr), i(corr), Evans diagrams, polarization resistance and Tafel slopes) were analyzed. The microstructure of the different dental materials was observed before and after corrosion processes by optical and electron microscopy. It can be observed that the mechanical load produces an important decrease of the corrosion resistance. The cast and machined titanium had the most passive current density at a given potential and chromium-nickel alloy had the most active critical current density values. The high gold content alloys have excellent resistance corrosion, although this decreases when the gold content is lower in the alloy. The palladium alloy had a low critical current density due to the presence of gallium in this composition but a selective dissolution of copper-rich phases was observed through energy dispersive X-ray analysis.  相似文献   
866.
Two selective H2-histamine agonists, dimaprit and impromidine, have been tested for their action on histamine release from human basophils and rat mast cells.IgE-mediated basophil histamine release was inhibited by stimulation of histamine H2-receptors. However, differences between the actions of both dimaprit and impromidine were noticed. Both impromidine and dimaprit had no specific effect on 48/80-induced histamine release from rat mast cells, although the latter in higher concentrations either slightly increased spontaneous histamine release or non-specifically inhibited compound 48/80-induced release.The results are consistent with the view that activation of adenylate cyclase via H2-histamine receptors might be an important regulatory mechanism of histamine release from human basophils but not from rat mast cells.  相似文献   
867.
868.
The immunogenic properties of 17beta-estradiol, immobilized in negatively charged polymer gels, were investigated, and the specificity of antibodies produced was analyzed. The polymer gels developed were composed of a hydrophobic estradiol core surrounded by hydrophilic polyanions as corona. As an immunogen, it was conceived to function via a dual mode, that is as a hapten-delivery system (prolongation effect) and as a polyelectrolyte adjuvant. Polymer gels containing estradiol appeared to possess a high estradiol-specific immunogenicity even without the addition of traditional adjuvants. A comparative study of estradiol trapped in polymer gels versus estradiol conjugated to bovine serum albumin (BSA.E) + Incomplete Freund's Adjuvant (IFA) mixtures revealed similar immunogenic properties in terms of induction of specific antibodies. Following a short immunization procedure based on the use of 17beta-estradiol immobilized in polymer gels, we developed 10 specific monoclonal antibodies with Kd values ranging between 1.2 X 10(-7) and 8 X 10(-8) M.  相似文献   
869.
The relationship between type 2 diabetes and osteoporosis has not been well established. We studied a population composed of 161 post-menopausal women with type 2 diabetes and a control group. We examined bone mineral density with the dual-energy X-ray absorptiometry(DXA) technique at the lumbar and femoral regions and in a subgroup of patients, we also measured the levels of markers of bone remodelling. We found significantly higher levels of bone mineral density at the lumbar and femoral levels in the diabetic subjects compared with the control group. Moreover, we found higher level of urinary calcium in the controls. On the basis of these results, we suggest that osteoporosis cannot be considered a complication of type 2 diabetes.  相似文献   
870.
The quality of results of flow cytometric DNA content analysis of formalin-fixed, paraffin-embedded tissue may be affected by a number of preanalytical variables. We performed flow cytometric DNA content analysis on two types of benign tumors to investigate the effect of a prominent lymphocytic component: Warthin's tumor (N = 20) and benign thymoma (N = 8). Malignant tumors (N = 23) were included as DNA aneuploid controls. All tissues studied were archival material processed using Hedley's technique either without prolonged rehydration in water (day 0 samples) or with 24- or 48-hour rehydration (day 1 and day 2 samples, respectively). Image cytometric DNA ploidy analysis was also performed on most cases. Eight cases (40%) of Warthin's tumor and five cases (63%) of benign thymoma showed either hyperdiploid peaks or marked asymmetry on the day 0 DNA histograms; nine of the malignant tumors were aneuploid. The DNA histogram abnormalities of the benign tumors could be gated out by excluding the lymphocyte nuclei. None of the DNA indices of the benign tumors corresponded with expected deviations based on published chromosomal studies. All of the DNA histogram abnormalities of the benign tumors disappeared and/or fused with the main peaks on the day 1 or day 2 samples, except for one case of benign thymoma. All the DNA aneuploid peaks on the malignant tumors persisted with prolonged rehydration. Image cytometric DNA analysis showed a diploid pattern in all benign tumors. We conclude that a high lymphocyte content may be a cause of false aneuploidy in these benign tumors. Furthermore, the degree of rehydration appears to be an important factor in achieving optimum fluorochrome staining of DNA.  相似文献   
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