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71.
One hundred ASA I orthopaedic surgical patients (four randomized groups) were anaesthetized using continuous propofol and intermittent fentanyl (TIVA), with controlled ventilation via a tracheal tube in groups 1 and 2, and a laryngeal mask airway (LMA) in groups 3 and 4. Neuromuscular blockers were used in groups 1 and 3 only. There were no significant differences between groups in total anaesthetic requirements, as assessed by cardiovascular variables and movement. Coughing interfered with surgery and made controlled ventilation difficult to manage. In contrast, movement not associated with coughing did not impair surgery or ventilation. Patients in group 2 (tracheal tube, no neuromuscular blocker) required more interventions for coughing than the other groups, while patients in group 4 (LMA, no neuromuscular blocker) needed more boluses for movement than groups 1 and 3. Groups 1 and 2 (tracheal tube) had significantly higher heart rates and mean arterial pressures than groups 3 and 4 for varying periods up to 5 min after insertion of the airway management device. There was no correlation between mean arterial pressure and plasma concentrations of catecholamines related to insertion of either the tracheal tube or LMA. The LMA was found to be a highly effective device for controlled ventilation in TIVA and easier to manage than the tracheal tube in the absence of neuromuscular blockers.  相似文献   
72.
IL-15 has recently been detected in the synovium of patients with rheumatoid arthritis. IL-15-activated T cells induce significant TNF-alpha synthesis by macrophages via a cell contact-dependent mechanism, suggesting a key regulatory role for IL-15. Here, we report that the administration of a soluble fragment of IL-15Ralpha into DBA/1 mice, profoundly suppressed the development of collagen-induced arthritis. This was accompanied in vitro by marked reductions in Ag-specific proliferation and IFN-gamma synthesis by spleen cells from treated mice compared with control mice and in vivo by a significant reduction in serum anti-collagen Ab levels. These data directly demonstrate a pivotal role for IL-15 in the development of inflammatory arthritis and also suggest that antagonists to IL-15 may have therapeutic potential in rheumatic diseases.  相似文献   
73.
129 children with exstrophy of the bladder underwent primary surgical reconstruction according to G. A. Bairov. Morphofunctional findings in these children gave grounds for determination of three degrees of the bladder congenital defects. 39 patients had defect of the 1st degree, 53 of the 2nd and 37 of the 3d degree. The results of plastic reconstruction of the bladder with local tissue support the validity of such procedure only for patients with the congenital defect degree I. For degree II the benefit is relative. In degree III plastic surgery in contraindicated.  相似文献   
74.
Kv1.3, a voltage-dependent potassium channel cloned from mammalian brain and T lymphocytes, contains multiple tyrosine residues that are putative targets for tyrosine kinases. We have examined the tyrosine phosphorylation of Kv1.3, expressed transiently in human embryonic kidney (or HEK) 293 cells, by endogenous and coexpressed tyrosine kinases. Tyrosine phosphorylation is measured by a strategy of immunoprecipitation followed by. Western blot analysis, using antibodies that specifically recognize Kv1.3 and phosphotyrosine. Coexpression of the constitutively active tyrosine kinase v-src, together with Kv1.3, causes a large increase in the tyrosine phosphorylation of the channel protein. This phosphorylation of Kv1.3 can be reversed by treatment with alkaline phosphatase before Western blot analysis. Coexpression with a receptor tyrosine kinase, the human epidermal growth factor receptor, also causes an increase in tyrosine phosphorylation of Kv1.3. The effects of endogenous tyrosine kinases were examined by treating Kv1.3-transfected cells with the specific membrane-permeant tyrosine phosphatase inhibitor pervanadate. Pervanadate treatment causes a time- and concentration-dependent increase in the tyrosine phosphorylation of Kv1.3. This increased tyrosine phosphorylation of Kv1.3 is accompanied by a time-dependent decrease in Kv1.3 current, measured by patch-clamp analysis with cell-attached membrane patches. The pervanadate-induced suppression of current and much of the channel tyrosine phosphorylation are eliminated by mutation of a specific tyrosine residue, at position 449 of Kv1.3, to phenylalanine. Thus, there is a continual phosphorylation and dephosphorylation of Kv1.3 by endogenous kinases and phosphatases, and perturbation of this constitutive phosphorylation/dephosphorylation cycle can profoundly influence channel activity.  相似文献   
75.
The use of the standard chemical technic for measuring intestinal glucose absorption was compared with a new double-label radioisotope technic. Glucose absorption and water flux in the mouse small intestine were measured by both methods. The results indicated that the 2 approaches yield almost identical values. The radioisotope technic utilized [14C] polyethylene glycol to measure water flux and [3H] glucose. The technic was found to be reliable, rapid, and applicable to small samples and other substrates. It is particularly suited to absorption studies in small animals such as the mouse, where sample size is limited. The study also showed that the polyethylene glycol recovery rate from the mouse intestine was 97.8%, indicating that it is a valid absorption marker in this species.  相似文献   
76.
The molar ratio between glycan and teichoic acid was studied in the cell wall of Actinomyces thermovulgaris. A chain of teichoic acid consisting of 13 glycerophosphate units was found to correspond to 6--7 disaccharide units of glycan. The cell wall contains 31% of the glycan of the glycopeptide and 25% of teichoic acid. The content of glycan was calculated using the concentration of muramic acid in the wall. The cell wall was found to contain 1.02% of O-acetyl groups.  相似文献   
77.
78.
This review leads to a concept in which the tissues of the dentogingival junction are dynamic rather that static. Even when they are pathologic, they can be reconstituted by repair. Both their cellular and extracellular components exhibit a high rate of turnover. Some of the cells are specialized for specific functions, such as attachment formation, and do not generate additional cells, but generative pools are always nearby. The cells are capable of movement and of positional change. The junctional epithelium can advance and retract. The cuticle width is alterable. The entire tissue is capable of regeneration after wounding. This dynamic group of tissues is well adapted for the healing of direct injuries produced during mastication. The tissues do remarkably well, over long periods, in their response to periodontal disease, whether due to direct bacterial or toxic damage, or to indirect damage via the migration of inflammatory cells into the lesion. The tissues show a capacity for repair and regeneration following the elimination of plaque formation and the resultant resolution of the inflammatory infiltrate. The complete story is not yet developed. The past 60 years are replete with fine contributions by distinguished workers. Additional contributions continue to be made. The inheritance from our predecessors has been used well and our expanded knowledge in this area now serves as the conceptual framework for further study.  相似文献   
79.
80.
At the final stage of long-term space flights first aid should be rendered in a specific way in cases of critical situations. Resuscitation and anesthesiology measures should be applied, if necessary, after study of flight-induced changes in the vital organs and systems. The paper describes the most important factors that should determine the tactics of resuscitation-anesthesiology support of the immediate postflight stage, if theoretically feasible acute life-endangering states develop. It also presents substantiated correction of routine clinical protocols of resuscitation aid.  相似文献   
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