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991.
J M Pérez Trullen P J Modrego Pardo M Vázquez André J J López Lozano 《Biomedicine & Pharmacotherapy》1992,46(8):375-376
Benzodiazepines are drugs with a good tolerance that are widely used for the treatment of anxiety. Extrapyramidal side-effects are unusual. Diazepam is effective for the treatment of drug-induced dystonias, nevertheless there are some reports of Diazepam-induced dystonia. We report a case history of a patient who developed oromandibular dystonia after taking Bromazepam. The possible mechanisms that cause drug-induced dystonia are described. 相似文献
992.
993.
J. Bácskai K. Martinusz E. Czirók G. Inzelt P.J. Kulesza M.A. Malik 《Journal of electroanalytical chemistry (Lausanne, Switzerland)》1995,385(2):241-248
An electrochemical quartz crystal microbalance (EQCM) was employed to monitor directly the growth of nickel(II) hexacyanoferrate(III) (NiHCNFe) films on gold substrates during electrodeposition as well as a result of sol-gel aggregation in colloidal nickel ferricyanide solutions used for modification. Frequency changes due to mass changes of the gold/crystal working electrode were correlated with cyclic voltammetric (CV) data. Evidence is also provided for the sorption of counter-cations (Li+, Na+ and K+), and associated water molecules, during redox reactions of the film. There is a strict relationship between the amount of alkali metal ions incorporated into the film during reduction, or excluded from the film during oxidation, and the frequency changes during EQCM measurements. The amount of solvent (H2O) transferred and sorbed in the NiHCNFe film reflects the degree of hydration of the investigated counter-ions. Anions also seem to participate in NiHCNFe electrochemistry, but their role is much less pronounced. 相似文献
994.
Roger L. Novack Einar Stefánsson Diane L. Hatchell 《Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie》1990,228(1):128-133
The effects of acute intraocular pressure (IOP) on the reduction/oxidation ratio of cytochromea,a
3 were measured from intact cat optic nerve by microfiber reflection spectrophotometry. This enabled the real-time analysis
of optic nerve-head oxidative metabolism following IOP or mean arterial pressure (MAP) changes. Findings included: (1) cytochromea,a
3 became more reduced and relative blood volume decreased at lower perfusion pressures, even at IOP of <20 mm Hg; (2) metabolic
inhibition began at variable perfusion pressures but invariably progressed as perfusion pressure declined; and (3) increased
IOP or decreased MAP caused metabolic inhibition. These findings demonstrate that: (1) optic nerve metabolic dysfunction is
possible at low IOPs; (2) lowering IOP can reverse metabolic dysfunction; (3) the metabolic response is dependent on IOP and/or
MAP changes; and (4) the metabolic inhibition is related to optic nerve ischemia.
Presented at the 8th International Congress of Eye Research-Symposium on Retinal Oxygenation, San Francisco, September 1988 相似文献
995.
Marie V. St-Pierre K. Sandy Pang 《Journal of pharmacokinetics and pharmacodynamics》1995,23(3):243-266
Previous mouse liver studies with diazepam (DZ),N-desmethyldiazepam (NZ), and temazepam (TZ) confirmed that under first-order conditions, DZ formed NZ and TZ in parallel.
Oxazepam (OZ) was generatedvia NZ and not TZ despite that preformed NZ and TZ were both capable of forming OZ. In the present studies, the concentration-dependent
sequential metabolism of DZ was studied in perfused mouse livers and microsomes, with the aim of distinguishing the relative
importance of NZ and TZ as precusors of OZ. In microsomal studies, theK
ms andV
maxs, corrected for binding to microsomal proteins, were 34 μM and 3.6 nmole/min per mg and 239 μM and 18 nmole/min per mg, respectively,
forN-demthylation andC
3-hydroxylation of DZ. TheK
ms andV
maxs forN-demethylation andC
3-hydroxylation of TZ and NZ, respectively, to form OZ, were 58 μM and 2.5 nmole/min per mg and 311 μM and 2 nmole/min per
mg, respectively. The constants suggest that at low DZ concentrations, NZ formation predominates and is a major source of
OZ, whereas at higher DZ concentrations, TZ is the important source of OZ. In livers perfused with DZ at input concentrations
of 13 to 35 μM, the extraction ratio of DZ (E{DZ}) decreased from 0.83 to 0.60. NZ was the major metabolite formed although its appearance was less than proportionate
with increasing DZ input concentration. By contrast, the formation of TZ increased disporportionately with increasing DZ concentration,
whereas that for OZ decreased and paralleled the behavior of NZ. Computer simulations based on a tubular flow model and thein vitro enzymatic parameters provided a poorin vitro-organ correlation. TheE{DZ}, appearance rates of the metabolites, and the extraction ratio of formed NZ (E{NZ, DZ}) were poorly predicted; TZ was incorrectly identified as the major precursor of OZ. Simulations with optimized parameters
imporved the correlations and identified NZ as the major contributor of OZ. Saturation of DZN-demethylation at higher DZ concentrations increased the role of TZ in the formation of OZ. The poor aqueous solubility (limiting
the concentration range of substrates usedin vitro), avid tissue binding and the coupling of enzymatic reactions in liver, favoring sequential metabolism, are possible explanations
for the poorin vitro-organ correlation. This work emphasizes the complexity of the hepatic intracellular milieu for drug metabolism and the need
for additional modeling efforts to adequately describe metabolite kinetics.
This work was supported by the Medical Research Council of Canada (MA-9104). 相似文献
996.
Priv.-Doz. Dr. Andreas Dávid Axel Ekkernkamp Gert Muhr 《Operative Orthopadie und Traumatologie》1994,6(3):196-207
Operationsprinzip Korrektur eines Pes equinus adductus durch keilf?rmige Resektion des Chopart-Gelenkes mit Keilbasis dorsolateral. Bei gleichzeitigem
Pes varus keilf?rmige Resektion des subtalaren Gelenkes mit Keilbasis lateral (Lange 1962 [7], Myerson et al. 1986 [8], Witt
et al. 1985 [13]) (Abbildungen 1a bis 1f).
Bei gleichzeitigem Tarsaltunnelsyndrom Dekompression des Nervus tibialis durch Spaltung des Retinaculum musculi flexorum.
Zur Korrektur von Krallenzehen Resektion der jeweiligen distalen Grundphalangen nach Hohmann; bei flektierten Endgelenken
Resektion der distalen Mittelphalangen. (Auf diese Techniken wird hier nicht eingegangen).
相似文献
997.
Milton Carlos Gon?alves Salvador Accácio Lins do Valle Mariana Carvalho Mandim Ribeiro Jefferson Ricardo Pereira 《Journal of applied oral science : revista FOB》2007,15(1):9-13
A group of destructive changes occurring in jaws in patients with maxillary complete dentures and mandibular removable partial dentures (bilaterally) has been described in the literature as the combination syndrome. However, this condition is not clinically observed in all patients. The aim of this study was to establish the prevalence index on signs of combination syndrome and to verify whether these changes also occurred in patients rehabilitated with a mandibular removable partial denture (unilaterally). Sample was composed of 44 patients, completely edentulous in the maxilla. Thirty-two patients had a Kennedy Class I removable partial denture and 12 a Kennedy Class II. Three major alterations were observed in 20.5% of the studied population. Nevertheless, these changes were present only in 25% of patients with Kennedy Class I removable partial denture. Based on the findings of this study, it can be concluded that patients with Kennedy Class II removable partial denture do not have similar signs that lead to the combination syndrome’s condition. 相似文献
998.
999.
1000.
D Martínez-Ares I Martín-Granizo Barrenechea J Souto-Ruzo J Yá?ez López A Pallarés Peral J L Vázquez-Iglesias 《Revista española de enfermedades digestivas》2005,97(12):877-886
INTRODUCTION: Colon cancer is one of the main causes of cancer death. Diagnosis requires the examination of the entire large bowel by means of radiological or endoscopic techniques. Many patients suspect of colon cancer are referred for colonoscopy but nevertheless this suspicion is not confirmed after endoscopic examination. The objective of this study is the evaluation of the reliability of abdominal ultrasound in the diagnosis of these tumors. MATERIAL AND METHOD: We selected patients suspect of colon cancer referred to the endoscopy unit for a colonoscopy. An abdominal ultrasound was carried out on all patients prior to the endoscopy. Considering the endoscopic examination as a gold standard, the sensibility, specificity, positive predictive value (PPV) and negative predictive value (NPV) of the ultrasonography were evaluated. Likewise, a series of analytical and clinical parameters were evaluated, in an attempt to establish associated factors of a colon cancer. The statistical analysis was carried out by means of the statistical package SPSS 12.0 for Windows. RESULTS: 145 patients were included in the study (56.6% males) with an average 66.72 years of age (22-89). A cancer was diagnosed in 42 cases (28.9%). In the diagnosis of colon cancer, abdominal ultrasound presents a sensitivity of 79.06%, a specificity of 92.15%, a PPV and a NPV of 80.9% and of 91.2%, respectively. Excluding from the analysis lesions of the rectal ampulla, which cannot be adequately evaluated by means of ultrasound, the figures for sensitivity, specificity, PPV and NPV increase to 91.8, 92.1, 80.9 and 96.9% respectively. The univariate analysis showed that an age over 65 years and the presence of microcytosis are associated to a greater risk of colon cancer while after multivariate analysis only the presence of microcytosis resulted to be an independent predictive factor of cancer. CONCLUSIONS: Abdominal ultrasound presents high sensitivity, specificity, PPV and NPV in the diagnosis of colon cancer. The combination of an ultrasonography and a rectoscopy permits us to rule out the presence of a colorectal carcinoma. In patients with microcytosis of 65 years and over, if there is strong clinical suspicion, a negative ultrasound may not be sufficient to rule out a colorectal neoplasia. 相似文献