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Zusammenfassung In einer Stichprobe von 382 schweren Drogenkonsumenten wurden Art und Ausmass des Drogenkonsums unter Berücksichtigung der Applikationsart der Stoffe erfragt und die Angaben einer Faktorenanalyse unterworfen. Es bildeten sich drei Faktoren mit den Kurzbezeichnungen «intravenös applizierte illegale Drogen», «oral applizierte illegale Drogen» und «oral applizierte Medikamente». Dies weist darauf hin, dass sich «intravenös spritzen» von den übrigen Applikationsarten eindeutig unterscheidet und dass die Definitionen des Betäubungsmittelgesetzes ein starkes Kriterium für die Einstellung der Drogenkonsumenten den Stoffen gegenüber ist. Pharmakologische Gesichtspunkte und solche der subjektiven Wirkung der Stoffe erlangen daneben kaum sichtbare Bedeutung.
Drugs and their modes of application — a factor analytic inquiry of drug abuse
Summary In a sample of 382 heavy users mode and extent of drug abuse were inquired. Factor analysis of the data gave three factors named i.v. applicated illegal drugs, oral applicated illegal drugs and oral applicated medicaments for short. Results show that attitudes of the drug users towards their drugs are strongly influenced by the mode of application and the definitions of the drug laws, whereas pharmacological aspects and subjective effects have hardly any demonstrable importance.

Drogues et leurs modes d'application — une enquête concernant la consommation abusive de drogues utilisant l'analyse factorielle
Résumé Une enquête sur mode et quantité de l'abus de drogues a été faite dans un échantillon de 382 graves consommateurs de drogues. L'analyse factorielle des données mène à trois facteurs abbréviés: «drogues illégales appliquées i.v.», «drogues illégales appliquées per os» et «médicaments appliqués per os». En regardant ces résultats on peut dire que les attitudes des consommateurs envers les drogues sont tout d'abord influencées par la mode d'application et les définitions des lois concernant les narcotiques, pendant que des points de vue pharmacologiques et les effects subjectifs n'ont peu d'importance.
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Nitric oxide synthase (NOS) activity has been detected previously in the mammalian cochlea at a light microscopic level. Here we present results of electron microscopic analysis for post-embedding immunoreactivity of neural-type NOS I in the cochlea of the guinea pig. Strong enzyme immunoreactivity was identified in the cytoplasm of inner and outer hair cells. Gold-labeled NOS I antibodies were mainly located in electron-dense areas of the cytoplasm, whereas electron-lucent regions of the receptor cells were nearly free from any immunoreactivity. In both types of hair cells anti-NOS I antibodies were also visible in the cuticular plates, hair bundles and nuclei. Further ultrastructural analysis revealed that the submembranous cisternae of the outer hair cells were nearly free from any reaction product, demonstrating that the whole cytoplasm of this hair cell was not immunoreactive. Other NOS I immunoreactivity was identified in the cuticular plates of the inner and outer pillar cells and in the cytoskeletal elements located in the apical parts of Deiter cells, forming the lamina reticularis or in cytoskeletal-containing regions in basal Deiter cells. Anti-NOS antibodies were visible in the nuclei of various cell types. Our findings suggest that nitric oxide produced by NO I synthase in the organ of Corti may act as a modulator of hair cell physiology during the processes of signal transduction with frequence selectivity.  相似文献   
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After oral administration of the organic calcium channel blocker diltiazem to guinea pigs for 7 days, calcium ions were precipitated with potassium antimonate in the cochleae. The spatial distribution of the precipitates was studied by energy-filtering transmission electron microscopy and the amount of the ultrastructural reaction products formed was determined semiquantitatively by an image processing system. Compared with untreated control ears, the number of the formed precipitates was reduced drastically in the inner hair cells after diltiazem treatment. In addition, electron microscopic analysis revealed that the number of calcium precipitates attached at the basolateral membrane of the outer hair cells was clearly reduced when compared with untreated control specimens. A large number of histochemical reaction products could be identified in the basilar membrane and were also observed in the untreated control specimens. The spatial distribution of the calcium precipitates in the lamina reticularis was not affected by diltiazem treatment and calcium precipitates could be identified within different cell membranes. The technique used was considered to be helpful for identifying calcium channels ultrastructurally in intact undissected tissues and to support light microscopic analyses and patch-clamp electrophysiological measurements.  相似文献   
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Electron spectroscopic imaging (ESI) was used to analyze the element content of melanin granules in the stria vascularis seen in ultrathin sections of Spurr-embedded cochleae of the guinea pig. To determine element composition, ESI images were taken at different ionization edges, and non-specific background signals were subtracted digitally by an image processing system. The presence of calcium and nitrogen in the melanin granules could be demonstrated clearly. The calcium identified in the melanin granules was then compared with the spatial distributions of calcium binding sites after the application of an antimonate precipitation method, which was used to localize loosely bound calcium. Despite a high calcium concentration within the granules, only very small single scattered calcium precipitates could be detected between these structures as compared with the amount of calcium precipitates attached to the plasma membrane or located within the cell nuclei. The nearly complete absence of precipitates within the melanin granules after the application of antimonate suggests differences in calcium binding and mobility involved in various physiological processes of ion balance regulation within the stria vascularis. Received: 14 October 1997 / Accepted: 11 February 1998  相似文献   
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Tamoxifen, which is used for treating breast cancer, exhibits estrogenic and antiestrogenic characteristics, depending on the tissue. In the human breast it acts as an antiestrogen, whereas estrogenic effects have been reported on endometrium and bone. The purpose of this study was to determine whether tamoxifen (TAM) prevents bone loss in elderly, postmenopausal women. Bone mineral density of the lumbar spine (SBD) was measured in elderly women (at least 10 years after menopause) 5 years after stage I or II breast cancer (n=111). The results showed that SBD in untreated patients (n=74) was significantly lower (p0.05) than SBD in patients (n=37) treated with TAM over 5 years. In a subgroup of patients (n=24) with positive estrogen receptor status, changes in SBD 12 months after discontinuation of 5-year TAM therapy were measured and compared with the changes of extended TAM treatment over a sixth year. Twelve months after withdrawal of 5-year TAM medication (n  相似文献   
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