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71.
The thiocarbamate antimycotics tolnaftate and tolciclate blocked sterol biosynthesis in fungal cells and cell extracts, with accumulation of squalene. This point of action was confirmed by the direct inhibition of microsomal squalene epoxidase from Candida albicans. There was no inhibition of other steps in ergosterol biosynthesis. In whole Candida cells, ergosterol biosynthesis inhibition was not complete at drug concentrations up to 100 mg/liter, whereas full inhibition occurred in a cell-free test system. Rat liver cell-free cholesterol biosynthesis was much less sensitive to the drugs. The biochemical action of tolnaftate and tolciclate is thus similar to that of the allylamine antimycotics naftifine and terbinafine.  相似文献   
72.
Four outbreaks of influenza B infection occurred in Houston, Texas in the years 1976-1984. In the Houston Family Study, age-related infection and illness rates in the recent two epidemics resembled those reported previously. A total of 118 persons, including 35 children followed from birth, were followed longitudinally through this entire period and 331 persons were studied through at least two outbreaks. Fifty-nine (88%) of 67 children studied for four outbreaks were infected and 25% had a second infection; about half of the adults had one infection but only one of 51 was reinfected. Infection rates were proportionally lower for those followed through 2-3 outbreaks. Those with documented infection were protected decreasingly over time against reinfection and associated illness in subsequent epidemics. Such protection decreased in efficacy from 65% after 2-3 years, to 46% after 4-5 years, and to no protection after seven years.  相似文献   
73.
The States of Mind (SOM) model provided a framework for assessing the balance between self-reported positive and negative affects in a sample of 39 outpatients with major depression and 43 healthy control subjects. The SOM model proposes that healthy functioning is characterized by an optimal balance of positive (P) and negative (N) cognitions or affects (P/(P + N) approximately 0.63), and that psychopathology is marked by deviations from the optimal balance. Research thus far has focused on the functional significance of cognitive rather than affective balance. Within this framework, we hypothesized that patients in untreated episodes of major depression would balance their positive and negative affects at the same level where depressed patients in other studies have balanced their positive and negative cognitions--namely, at P/(P + N) approximately 0.37. Points and confidence interval (CI) estimation procedures yielded results (mean = 0.35, 95% CI = 0.30 - 0.40) consistent with this hypothesis in a sample of 39 depressed male outpatients. Correlational analysis indicated that affect balance is inversely related to symptom severity as measured by self-report (Beck) and clinician-rating (Hamilton) scales.  相似文献   
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Burst-suppression EEG (BS-EEG) after cardiopulmonary resuscitation implies a bad prognosis, but little is known of the temporal dynamics of postanoxic BS-EEG. The authors studied 24 consecutive patients who developed BS-EEG within 24 hours after cardiopulmonary resuscitation, and followed 20 of these patients with serial EEGs. Except for one patient, BS-EEG was followed by another EEG pattern within 1 day, mainly areactive alpha EEG (n = 6), isoelectric EEG (n = 5), generalized continuous epileptiform discharges (n = 4), or theta; EEG (n = 3). The coexistence of different EEG patterns in the same recording was seen in 10 patients. Serial recordings disclosed a variety of EEG sequences with (often subtle) transitions between the different EEG patterns, including reappearance of BS-EEG. Postanoxic BS-EEG is followed by a variety of EEG sequences composed of different EEG patterns, each of which is recognized as an unfavorable sign in and of itself. The coexistence of different unfavorable EEG patterns in the same recording, and transitions between these EEG patterns in subsequent recordings, are common in patients with postanoxic BS-EEG. It seems reasonable to speculate that BS-EEG and subsequently evolving EEG patterns in anoxic encephalopathy reflect different forms of neocortical dysfunction, which occur at different stages of a dynamic process, leading ultimately to severe neuronal loss.  相似文献   
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Treatment of juvenile patients with a missing maxillary incisor is difficult, because an implant cannot be placed until growth is completed. The other minimally invasive alternatives are also problematic: Removable dentures are rarely accepted by juvenile patients, and the conventional resin-bonded fixed partial denture often provides a poor esthetic result because the metal retainer causes the abutment teeth to lose their natural translucency and to become grayish. Moreover, the alveolar ridge defect makes it easy to identify the prosthesis in the pontic area. The present case report describes the prosthetic treatment of a juvenile patient who had lost a maxillary incisor to trauma. To avoid the disadvantages of conventional therapies, subepithelial connective tissue was grafted to reshape the alveolar ridge. The space was closed with an all-ceramic resin-bonded fixed partial denture.  相似文献   
79.
The purpose of this study was to evaluate the influence of composition and deformation of biomedical stainless steels on mechanical properties, magnetic properties, and MRI artifacts. Type 304 and Type 316L samples were prepared using standard wire-drawing techniques. Mechanical properties were determined using standard test methods. The amount of ferromagnetic phase present was estimated using a Severn Gage and x-ray diffraction. Magnetic field attraction and artifacts were determined using previously described techniques. The strength of both steels increased significantly with increasing deformation. None of the type 316L wires transformed to the magnetic phase. The amount of magnetic phase in the type 304 wires increased with increasing deformation. There was no magnetic field attraction, and artifacts were minimal for all of type 316L wires and the undeformed type 304 wire. Deflection and artifacts were significant for the deformed type 304 stainless steel. These results provide guidance regarding the use of type 304 and type 316L stainless steels for bioimplants. In this regard, type 316L stainless steel seems to be a more acceptable material with respect to MR compatibility.  相似文献   
80.
Truncus Arteriosus With Patent Ductus Arteriosus and Normal Aortic Arch   总被引:1,自引:0,他引:1  
In hearts with a common arterial trunk (truncus arteriosus), there is almost always an inverse development of the aortic arch and the ductus arteriosus. Truncus with a normal aortic arch and a patent ductus is a rare echocardiographic and surgical finding. In this report, we describe 2 neonates in whom truncus arteriosus with a normal aortic arch and a medium or large patent ductus was diagnosed by preoperative echocardiography (without catheterization) and confirmed intraoperatively.  相似文献   
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