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991.
The concept of treatment-resistant schizophrenia cannot be defined as this of resistant depression: schizophrenia is a long-term illness; its evolution is almost always influenced by neuroleptics--but complete recovery is rare. French psychiatry tends to use clinical-empirical criteria, while english speaking studies prefer quantitative criteria, by extended use of clinical and psycho-social scales. The definition of resistant schizophrenia by Kane et al. is a typical example of this method of work. We propose to overview the limits of neuroleptics efficiency in schizophrenia from three groups of studies: a) The effects of maintenance therapy: 24 studies of the last twenty years show that 2/3 of schizophrenics under neuroleptics maintain their remission over one or two years, opposed to less than 1/3 of those who discontinue their treatment. These data seem to be independant from the method of the study, the choice of the neuroleptic drug, the dose and the way of administration (per os or depot treatment). b) A second group of studies tries to define the clinical characteristics of treatment-resistant schizophrenia. French psychiatry uses an empirical graduation of neuroleptics clinical efficiency: these drugs are more effective on hallucinations than on delusional ideas--they are more effective on recent and acute hallucinations and delusions than on those of which course is chronic. Other studies specify predictive factors of poor response to neuroleptics, as few affective symptoms and presence of negative symptoms--a controversed factor. c) Not clinical factors of poor neuroleptics efficiency in schizophrenia begin to be studied.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
992.
The possibility that exposure to powerline frequency (60-Hz) magnetic fields might affect the form or intensity of epileptic seizures, induced by administration of pentylenetetrazol (PTZ) in rats, was examined. Male adult rats were exposed to either 60-Hz magnetic fields with intensities of up to 1.85 gauss (185 microT) or to a sham field condition, for 1 h prior to injections of PTZ (45-75 mg/kg). The subsequent seizures were monitored and recorded on videotape and any subsequent mortalities were noted. Exposure to 60-Hz magnetic fields prior to administration of PTZ was found to significantly (P less than 0.005) reduce the lethality of the drug-induced seizures. The LD50 for the sham-exposed group was 65.88 mg/kg, whereas for the 60-Hz magnetic field-exposed rats, the LD50 was 85.33 mg/kg. In some experiments exposure to the 1.0 and 1.5 gauss magnetic fields also produced significant (P less than 0.05) reductions in seizure durations. These findings suggest that acute exposure to low intensity 60-Hz magnetic fields has an inhibitory effect on the lethality and expression of PTZ-induced seizures in rats. Some possible mechanisms, which could account for these observed effects of magnetic field exposure on seizures, are discussed.  相似文献   
993.
Evaluation of alcoholism treatment effectiveness needs to be based on the healthy goals that alcoholics themselves identify as important. This research uses ethnography and grounded-theory methods to develop a model of recovering alcoholics' goal progression. The author spent 28 days in a treatment center, engaging in all patient activities, and observed and interviewed 42 participants to determine what they wanted from treatment. The research indicates that recovering alcoholics' goals develop through four stages. Certain kinds of behavior must be accomplished for an alcoholic to move from one stage to another. Behavior that facilitates and inhibits goal progression is identified.  相似文献   
994.
Glass ionomer restorative cement offers the clinician an alternative to bonded composite resin for restoration of certain lesions in primary teeth. This article details a step-by-step procedure for restoration of a smooth surface carious lesion in a primary incisor using an encapsulated glass ionomer restorative material and reviews advantages and limitations of the cement. A light-hardened glass ionomer liner/base that has proven useful as an enamel and dentin restorative is also described.  相似文献   
995.
996.
International Journal of Clinical Pharmacy - In order to calculate the minimum sterilization process conditions to obtain the generally accepted sterility level (less than 1·10?6...  相似文献   
997.
A detailed examination of quantitative relationships of pharmacological action with plasma and tissue concentrations of indomethacin has been undertaken in the rat, after single oral administration of two sustained release preparations. In this study, drug was assayed by high performance liquid chromatography, whereas antiinflammatory response was assessed through the carrageenin-induced edema test. Significant linear correlations (p less than 0.001) were found between logarithmically transformed percent inhibition of edema and logarithmically transformed plasma, as well as tissue levels of indomethacin. However, the lack of significance for partial correlation regarding tissue concentration, contrary to plasma concentration, suggests that pharmacological response is more closely related to the latter, indicating that antidematous effect is mediated via the circulating drug rather than a local action in target tissues. This assumption is further discussed from the equivalence point of view. The relevance of this type of study in the case of topical administration of indomethacin is addressed as well. Taking into account the predictive value of the rat paw edema test for clinical efficacy, relationships similar to those observed are to be expected in man. The high correlation existing between plasma concentration of indomethacin and its pharmacological effect justifies the development and use of sustained release preparations in order to improve the outcome of treatment with this nonsteroidal antiinflammatory drug.  相似文献   
998.
999.
The authors describe a method for silicone intubation of a single patent canaliculus associated with a nasolacrimal duct obstruction. Although bicanalicular intubation is always preferable when possible, unicanalicular stenting is necessary when only one canaliculus is patent. A chief advantage of this technique is that the lacrimal stent is inaccessible to the child and thus cannot be accidentally pulled out.  相似文献   
1000.
D J Harris  G O Waring  L L Burk 《Ophthalmology》1989,96(11):1597-1607
After penetrating keratoplasty in 52 eyes, keratography refraction and keratometry were used to select appropriate interrupted sutures for removal in order to reduce astigmatism. All eyes had one continuous and either 12 or 16 interrupted nylon sutures. The keratographs were examined retrospectively and separated into six groups on the basis of similar mire patterns. The removal of single sutures associated with three of these patterns reduced astigmatism by the following average amounts: symmetrical oval pattern, 0.44 diopters (D); D-shaped oval pattern, 2.07 D; and focal indentation pattern, 6.60 D. The other three patterns--mildly disrupted mires, incomplete mires, and uninterpretable mires--did not allow quantification of results. Examples of these keratographic patterns are presented and recommendations are made for their use in the management of astigmatism following penetrating keratoplasty.  相似文献   
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