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991.
High-frequency jet-ventilation (HFJV) was applied to 30 patients undergoing vertical partial surgery of the larynx for carcinoma of the vocal cords. This technique gave good surgical conditions as it interfered little with the air-ducts. It was carried out with a catheter of only 3 mm external diameter; control of ventilation during surgery was adequate, the average PaO2 being 27.9 +/- 5.6 kPa (209.3 +/- 4.2 mmHg) and the average PaCO2 5.4 +/- 1.4 kPa (40.5 +/- 10.5 mmHg). It avoided also the need for a tracheotomy. In the past, anaesthetic techniques were local anaesthesia combined with neuroleptanalgesia, endotracheal intubation or preoperative tracheotomy. None of these methods being satisfactory, our practice now includes first a nasotracheal intubation with an armoured tube at the beginning of the surgical procedure, followed by HFJV during the removal of the vocal cord, the tracheal tube being slightly pulled out. The tracheal tube is then put back in place before the thyroid cartilage is closed. The contra-indications are the same as those of HFJV. There are two types of complications: complications of HFJV itself, and postoperative complications due to the absence of tracheotomy. No accidents were observed. The only incidents seen were related to the lack of tracheotomy: subcutaneous oedema of the neck during the postoperative period in eight patients and moderate tracheobronchial congestion in five patients.  相似文献   
992.
It is still not known how T cells are activated, which T-cell surface structures transmit activation signals, and if antigen-presenting cells possess activation structures for T cells. We have studied whether the T-cell receptor (TcR) must be engaged for T-cell activation to occur. By using membrane-incorporated monoclonal antibodies, we artificially forced T cells to bind to antigen-presenting cells in a mixed lymphocyte reaction system and thereby bypassed the need for TcR engagement and also made it possible for any surface molecule on antigen-presenting cells to deliver a stimulatory signal to the T cells. Theoretically, T cells would become polyclonally activated by this procedure. However, we found that they did not, even though they were intimately bound to the antigen-presenting cell, thus demonstrating that the TcR must participate in antigen/MHC binding in order for the T cells to become activated. This study does not exclude the possibility that antigen-presenting cells possess structures that can activate T cells.  相似文献   
993.
Isolates of Haemophilus influenzae type b (Hib) can be divided into three antigenic groups based on their reactivities with a set of two monoclonal antibodies (MAbs) directed against epitopes in the oligosaccharide region of Hib lipooligosaccharide (LOS) (P. A. Gulig, C. C. Patrick, L. Hermanstorfer, G. H. McCracken, Jr., and E. J. Hansen, Infect. Immun. 55:513-520, 1987). Approximately 24% of Hib strains react with both of these LOS-specific MAbs. Immunoprecipitation experiments involving several of these strains indicated that the epitopes recognized by these MAbs resided in two different LOS molecules, both of which were synthesized by these particular Hib strains. In addition, Western blot (immunoblot) analysis of proteinase K-treated cell extracts of these strains that had been subjected to sodium dodecyl sulfate-polyacrylamide gradient gel electrophoresis revealed two different LOS staining patterns when they were probed independently with the two MAbs. Colony blot radioimmunoassay of hundreds of colonies of one of these Hib strains showed that each colony bound both MAbs. Immune electron microscopy confirmed that individual cells of this same Hib strain expressed both types of LOS molecule at the same time. An antibody accessibility radioimmunoassay was used to show that different Hib strains of this type varied in the relative amounts of each of the two MAbs that they could bind to their cell surfaces. These findings indicate that some Hib strains can synthesize two antigenically distinct LOS molecules simultaneously.  相似文献   
994.
995.
Changes in latencies of the visual evoked response (VER) during early post-natal development were examined in protein-deprived (PD) rats. The evoked response to light-flash stimulation was recorded in the dorsal lateral geniculate nucleus (dLGN) and on the surface of the visual cortex. In control rats, latencies of the cortical VER decreased rapidly up to 20 days and slowly thereafter. In PD rats, the latencies of the cortical VER were increased by 10-15 ms at 17 days; the developmental decrease was delayed by approximately 3 days. After 20 days, PD rats also went into a phase with slow decrease of the latencies, and the onset latency of the cortical VER was still increased by some 10 ms at 26/27 days. At this age, PD rats showed an increase in the latencies of the VER in the dLGN which was of similar magnitude to that in the cortical VER, indicating that alterations were more marked in the peripheral parts of the visual system at this stage of development. The findings are in agreement with previous studies indicating that there is a delay of visual system development in PD rats before 20 days. A maturational event which turns rapid into slow development at approximately 20 days in both C and PD rats turns this delay into a distortion of development. The delays and distortions of visual system development may be one causative factor for the functional deficit present in the visual cortex of adult PD rats.  相似文献   
996.
Combined teaching methods may improve recall and comprehension of discharge instructions. It is not clear from the study whether improved recall and comprehension resulted in better compliance. However, complications from head injuries, although rare, can be life threatening. Therefore it is recommended that emergency nurses present all instructions to the patient (or person accompanying the patient) by reviewing and explaining all medical terms and directions that the person must understand and follow. If additional time is available or the person does not appear to understand the instructions, reinforcement of content should be provided. It also is recommended that discharge instructions be written at a fifth-grade reading level, avoiding technical and medical terms. With research, emergency nurses can develop and evaluate effective and efficient teaching/learning strategies.  相似文献   
997.
998.
A G Lewis 《Postgraduate medicine》1989,86(3):141-4, 147-51
Initial assessment of common forefoot deformities by the primary care physician is quite feasible. A thorough history, examination of the foot with the patient standing and seated, assessment of the patient's footwear, and radiographic evaluation can often lead to gratifying relief with use of simple office measures. Even in cases that require referral to an orthopedic surgeon, interim relief of symptoms and the patient's increased awareness of the problem and its cause enhance the patient's understanding and the final outcome as well.  相似文献   
999.
A 53-year-old woman was examined at our medical center because of progressive dysphagia of 14 days' duration and a severe inability to open her mouth and swallow saliva. A barium esophagogram showed no obstruction, but pooling of barium in the hypopharynx suggested a neuromuscular disorder. The clinical diagnosis of tetanus was confirmed by electromyography. With appropriate therapy, the patient recovered during a period of 6 weeks. This case illustrates both an uncommon cause of dysphagia and an uncommon initial manifestation of tetanus.  相似文献   
1000.
A digital test of pelvic muscle strength for evaluation of a pelvic muscle exercise (PME) program was developed with a sample of 338 incontinent women living at home. Factors of perceived pressure, alteration of the vertical plane, and time were combined to form a 7-point scale ranging from 0 to 4. Test-retest for the anteroposterior score was r = .65, p less than .01 with interrater reliability, r = .91, p less than .01. Relationship to other variables and further development of the measure are discussed.  相似文献   
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