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1.
In 41 patients with recurrent sustained ventricular tachycardia and/or ventricular fibrillation an integrated pacemaker-defibrillator-system (PCD, Medtronic, model 7216 A or 7217 B) was implanted. In 21 out of 24 (88%) patients a new transvenous implantation technique in combination with a subcutaneous patch electrode was used. The implanted devices comprise antibradycardiac pacemaker functions, two different forms of antitachycardiac pacemaker functions (ramp and burst pacing), and internal cardioversion or defibrillation capabilities. During a mean follow-up of 8 months 147 episodes of ventricular tachycardia were detected, 131 of them were terminated successfully by antitachycardiac pacing; in 13 episodes internal cardioversion was applied to revert ventricular tachycardia. Twenty-seven episodes of ventricular fibrillation or rapid ventricular tachycardia (greater than 200/min) were detected and successfully terminated by internal defibrillation. In six patients with intermittent rapid atrial fibrillation, change of antiarrhythmic therapy was required to avoid activation of the device. The new integrated pacemaker-defibrillator systems improve therapy in patients with life-threatening tachyarrhythmias by reducing the number of internal cardioversions/defibrillations; the non-thoracotomy approach reduces the post operative risk.  相似文献   
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Teeth with white spot lesions (WSL) might be more prone to enamel loss during bracket debonding. This in vitro study compared enamel loss from teeth with (n = 14) and without (n = 14) WSL after polishing with low-speed finishing burs or disks (Sof-Lex, 3M ESPE, St Paul, Minn). Debonded surfaces were analyzed with a contact stylus profilometer, and digitized data were compared with baseline readings by using AnSur NT software (Regents, University of Minnesota, Minneapolis, Minn). Specimen surfaces were also examined with a scanning electron microscope. Two-way analysis of variance was performed to analyze the data. In teeth without WSL, the volume losses were 0.16 mm(3) for the bur group and 0.10 mm(3) for the disk group; the mean maximum depths were 47.7 microm for the bur group and 54.3 microm for the disk group. In teeth with WSL, the volume losses were 0.06 and 0.17 mm(3), and the mean maximum depths were 35.1 and 48.7 microm for the bur and disk groups, respectively. There were no significant differences in enamel loss between the 2 groups of teeth without WSL (P =.12). However, in teeth with WSL, the burs removed less enamel than the disks (P = 0.006). Scanning electron microscope examination showed that any damage on the enamel surface was usually located in the cervical third of the teeth. On most specimens, even though tooth surfaces appeared resin-free to the naked eye, there were remnants of it. The differences between groups were so small that they might be clinically insignificant.  相似文献   
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Sexual differentiation of dopaminergic neurons was studied in gender-specific cultures. Dissociated cell cultures were prepared from di- or mesencephalon of gestational day 14 rat embryos and raised in the absence or presence of 17 beta-estradiol or testosterone for up to 13 days in vitro (DIV). Developmental profiles of levels of dopamine (DA) and metabolites as well as capacity for vesicular storage of the transmitter were determined by HPLC. Tyrosine hydroxylase-immunoreactive (TH-IR) neurons were counted. Higher levels of DA were measured in female than in male cultures of both brain regions. In mesencephalic cultures, the differences in DA levels were fully accounted for by sex differences in numbers of TH-IR cells, whereas no sex differences in cell numbers were found in diencephalic cultures. Dihydroxyphenylacetic acid (DOPAC) levels and vesicular storage capacity matured faster in mesencephalic than in diencephalic cultures, but no sex differences were observed. Homovanillic acid (HVA) could not be detected except in 13-DIV mesencephalic cultures. Hormonal treatment did not erase sexual differentiation of dopaminergic neurons. Irrespective of the gender, however, both steroids decreased DA and DOPAC contents in diencephalic cultures but not in mesencephalic cultures. It is proposed that sexual differentiation of dopaminergic systems proceeds in a region-specific fashion and that neurogenesis and development of various parameters of dopaminergic activity may be differentially affected. Sexual differentiation of dopaminergic neurons may be initiated independently of the action of gonadal steroid hormones and may subsequently be modified by differences in hormonal environment.  相似文献   
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Venöse Thromboembolien (VTE) stellen eine häufige Morbiditäts- und Mortalitätsursache dar; die jährliche Inzidenz wird mit etwa 1 : 1 000 angegeben. Dabei sind verschiedene Risikogruppen zu unterscheiden, die sowohl durch endogene Faktoren (z. B. genetisch deteminierte Thrombophilie), viel häufiger aber durch exogene Faktoren (zugrundeliegende Erkankung) charakterisiert werden. Diese Heterogenität resultiert in Besonderheiten bei Prophylaxe und Therapie von VTE, auf die in dieser Darstellung eingegangen werden soll.  相似文献   
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BACKGROUND: For immunotherapeutic approaches, 'critical' amino acids (AAs) within allergenic epitopes are replaced with alternate AAs to eliminate IgE antibody binding. OBJECTIVE: To determine the critical AAs for IgE binding in beta-casein and beta-lactoglobulin (BLG). METHODS: Peptides of 10-14 AAs in length were synthesized on a derivatized cellulose membrane with single AA substitutions (alanine or glycine) at each position. Membranes were incubated with a pool of sera from 15 cow's milk-allergic patients and individual sera from six of the 15 patients. In cases where no decrease in binding occurred with a single AA substitution, peptides with two AA substitutions were generated and labelled. RESULTS: Using pooled patient sera, single AA substitutions led to complete elimination of binding to six of 11 peptides for beta-casein and to all six peptides for BLG. Substituting two AAs led to an elimination of binding to four of the remaining five beta-casein epitopes. However, in three of the 11 modified beta-casein peptides and five of the six BLG peptides, no decrease in IgE binding occurred in at least one individual patient. For these patients, critical AAs other than those defined by the patient serum pool were identified, indicating a heterogeneous pattern of IgE recognition. CONCLUSION: These results indicate that AAs critical for IgE binding are more heterogeneous than initially defined by pooled milk-allergic patient sera. For future immunotherapeutic interventions with mutated peptides, critical AAs should also be identified with individual patient sera to account for heterogeneity of IgE binding between patients.  相似文献   
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The effects of neuroleptics on facial action in schizophrenic patients.   总被引:3,自引:0,他引:3  
This paper describes the influence of neuroleptic therapy on facial action in drug-naive schizophrenics. In a comparative study of medicated and unmedicated schizophrenic patients, the coordinates of 12 small light-reflecting points, attached to subjects' faces, were computer-recorded and analyzed automatically during a semi-standardized clinical interview. In addition, facial activity in videotaped interviews was coded using the Facial Action Coding System (FACS). Each sample group comprised of eight patients with the DSM-III-R diagnostic criteria "schizophrenia" or "schizophreniform disorder". Subjects were studied on two occasions, one shortly after admission to the hospital, the other three weeks later. Group 1 was unmedicated during the first session, whereas group 2 was medicated throughout the study. Three weeks after the start of medication, at the second interview, both recording methods showed a reduction in facial activity and facial expression across all subjects in group 1. The facial action of patients in group 2, however, remained unchanged.  相似文献   
9.
In the present report we describe the preparation of LC-6.2HCl, a soluble derivative of the synthetic bispyrazole LC-6. Because the latter was practically insoluble in aqueous and organic media, experiments which indicated that it had antiallergic activity were confined to in vivo studies following its oral administration. The availability of soluble LC-6.2HCl made it possible to administer the drug i.v. or i.p. Through these routes it exhibited greater antiallergic activity than by the oral route, as judged by lower ID50's and by the achievement of 100% PCA inhibition. The latter result had not previously been attained orally with the base. Furthermore, when injected i.v. or i.p. LC-6.2HCl showed prolonged inhibitory activity, a valuable attribute of the parent compound. The in vivo activity of the soluble salt, which we describe, further establishes the potential therapeutic value of the drug.  相似文献   
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