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31.
Three dimensional computed tomography was performed in 150 children suffering from a bone lesion of the base of the skull and face. These lesions were either malformative, neoplastic, infectious or traumatic. 3D CT provided an essential anatomical approach to the lesions facilitating the choice of the most appropriate treatment. 3D CT is also indicated in the follow-up of these operated children, particularly of the growth of the operated bone segment and its relations with adjacent structures.  相似文献   
32.
Complex injuries of the foot are often overlooked, especially in the multiple injured patient, and they then lead to major loss of function. When the mechanism of injury suggests involvement of the foot, a clinical examination of the lower extremities should be included in the primary diagnostic procedures implemented in the multiply injured patient, followed by radiological examination once the patient's condition is stable. The condition of the soft tissues is of decisive importance in the prognosis of complex foot injuries, regardless of whether the damage to the foot is one component of a polytrauma or an isolated injury, which can also be life threatening. The diagnostic examinations selected should be adapted to the severity of the injuries in the particular multiply injured patient. Successful therapy involves stable internal fixation of injuries to bones and joints, though the external fixation options should be considered in the first instance, and carefully selected methods of temporary and definitive soft tissue reconstruction. The aim of treatment is the best possible reconstruction of the foot as a functional weight-bearing unit with intact soft tissue cover and a natural form. Good results can be achieved when there is close interdisciplinary cooperation between trauma (orthopedic) and plastic surgeons. Patient with severe injuries of this kind should be transferred to a trauma center as the first step toward this end.  相似文献   
33.
An original technique of voice rehabilitation following total laryngectomy based on the concept of a myomuscosal unit was originally described by Strome. Thirty-one cases of myomucosal shunts (MMS) are analyzed in the present report. The 14 initial cases failed because of a lack clinical and surgical experience and insufficient selection of the patients. Among the last 17 cases, 1 was lost to follow-up, 1 had an insufficient follow-up, and 2 patients refused to speak with the MMS instead of a patent shunt; 5 of the remaining patients had voices evaluated as excellent, 7 had voices interpreted as good and only 1 patient had a voice evaluated as poor. Aspiration was not a problem. Eleven patients were found to stenose their shunt, but fistula were recalibrated successfully. The MMs can be used safely in oncological surgery and only 1 of 31 deaths in our total experience was due to a local recurrence. These findings show that the MMS is a reliable procedure for voice restoration following total laryngectomy; a prosthesis is not required and there are currently no oncological limits to the procedure. However, a very close follow-up of the patients is required after surgery.  相似文献   
34.
Long-term potentiation (LTP) of mossy fiber responses in area CA3 of the rat hippocampus in vivo is blocked by naloxone, an opioid receptor antagonist, in a stereospecific and dose-dependent manner. LTP of commissural afferents to the same population of CA3 pyramidal cells is not attenuated by naloxone. This suggests that opioid receptors are involved in a mechanism of LTP induction that is specific to mossy fiber synapses, and that endogenous opioid receptors are involved in a mechanism of LTP induction that is specific to mossy fiber synapses, and that endogenous opioid peptides, presumably released as a result of mossy fiber stimulation, may be necessary for the induction of mossy fiber LTP. The naloxone sensitivity is limited to the induction phase of LTP, since naloxone does not reverse previously established LTP. These data suggest that LTP at the mossy fiber-CA3 synapse constitutes an NMDA receptor-independent, opioid receptor-dependent, form of hippocampal synaptic plasticity.  相似文献   
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Poly(3-hexylthiophene) (PT6), poly(3-octylthiophene) (PT8), poly(3-decylthiophene) (PT10) and poly(3-dodecylthiophene) (PT12) were synthesized by electrochemical and chemical polymerization. Investigation of these polymers by means of gel permeation chromatography indicates that the polymers prepared from the different monomers under similar conditions do not differ substantially considering molecular weight and molecular weight distribution. Bimodal distributions were found for electropolymerized polymers, and with increasing polymerization time, the high-molecular-weight and probably highly branched fraction increased relatively to the low-molecular-weight fraction. The microstructure of the polymers was investigated by nuclear magnetic resonance, and it has been found that the polymers exhibit more types of structural units than expected from a simple coupling of adjacent thiophene moieties in 2,5′-positions. Chemical oxidation with iron trichloride in chloroform gave soluble, high-molecular-weight poly(3-alkyl-thiophene)s with a rather low amount of irregular couplings, and these more regular polymers exhibited a higher degree of crytallinity. Room temperature conductivities of the oxidized polymers were between 0,1 and 30 S/cm depending on the polymerization conditions, but these values were rather independent of the length of the alkyl substituent.  相似文献   
38.
Twenty adolescent male sexual offenders were evaluated by penile plethysmography on two separate occasions. Stimuli consisted of 19, two-minute audiotaped cues. Test-retest reliability was demonstrated for 15 of the 19 audiotaped vignettes. The highest correlations were found for those sexual behaviors in which the adolescents had engaged.  相似文献   
39.
STUDY OBJECTIVE: To test the hypothesis that induced human graafian follicles consist of different steroidogenic cell types on the basis of their light scatter characteristics as determined by flow cytometry. DESIGN: Cross-sectional, observational study. SETTING: Flow cytometry laboratory. PATIENTS: Thirty-six follicular aspirates from nine consecutive patients undergoing in vitro fertilization for tubal factor infertility were evaluated. RESULTS: Two distinct luteal cell populations were recovered. Both populations were positive by Oil Red O staining, suggesting the presence of intracellular lipid. Neither population stained positively for the presence of HLe-1/CD45, an antigen present on all human leukocytes. CONCLUSIONS: Cellular heterogeneity exists within the granulosa cell compartment.  相似文献   
40.
F D Martinez 《Pediatrics》1991,87(2):190-198
Respiratory failure is almost certainly the cause of death in the majority of cases of sudden infant death syndrome (SIDS), but the mechanisms leading to it have not been elucidated. SIDS shares many environmental and socioeconomic risk factors with severe forms of bronchiolitis, and the age distribution of incident cases is similar. Present knowledge of lung and airway development during infancy, determinants of peripheral airway patency, changes in lung surface activity in infants with SIDS, and fluid film dynamics in small airways are reviewed. It is hypothesized that many cases of SIDS may be due to a final episode of progressive peripheral bronchial occlusion in infants with preceding critically diminished conductance of the smaller airways.  相似文献   
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