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81.
A cryptic multidrug resistance (MDR) system in Stenotrophomonas maltophilia, the expression of which is selectable by tetracycline, is described. Tetracycline resistance was the consequence of active efflux of the antibiotic, and it was associated with resistance to quinolones and chloramphenicol, but not to aminoglycosides or beta-lactam antibiotics. MDR is linked to the expression of an outer membrane protein (OMP54) both in a model system and in multidrug-resistant clinical isolates. 相似文献
82.
JA Carballido Rodríguez 《Canadian Metallurgical Quarterly》1997,21(7):641-643
A case of a large dentigerous cyst containing a canine tooth in the maxillary antrum is presented. This case is of interest due because of its extensiveness and the presence of a canine tooth in the roof of the maxillary sinus. In addition, this caused a right-sided epiphora. Enucleation of the cyst containing the ectopic tooth was made. 相似文献
83.
A Serrano Pascual C Merino Hernáez R Ochoa Mejías A Escolano Chamois J Golbano Ablanque I Otero Tejero M Sanz Redondo F Román Ruiz 《Canadian Metallurgical Quarterly》1997,21(6):631-635
BACKGROUND AND AIMS OF THE STUDY: Surgical treatment of functional tricuspid regurgitation associated with advanced valvular disease remains controversial, mainly due to the difficulty in choosing between valve replacement or reconstructive surgery. Failure to correct tricuspid regurgitation during valvular surgery carries a poor prognosis, as reoperation may represent a significant risk to the patient. Thus correct tricuspid valve surgery is vital to achieve improved early and long-term clinical results. METHODS: A total of 142 patients underwent concomitant tricuspid annuloplasty with mitral valve replacement and their clinical outcome was assessed. RESULTS: Overall hospital mortality rate was 11.3%. Seven patients died during follow up. The overall actuarial survival rate for 10 years was 74.1 +/- 14.2%. Postoperatively, 75.8% of the patients had no residual tricuspid insufficiency, while 24.2% had first- or second-degree tricuspid insufficiency and were treated medically. All patients were in NHYA functional class I or II postoperatively. CONCLUSION: Clinically, it is important to assess the severity of functional tricuspid insufficiency before and/or during the operation. Bicuspidalization annuloplasty for functional tricuspid insufficiency has provided good results, with a low incidence of reoperation and significant clinical improvement. The technique could be used in most patients with functional tricuspid regurgitation. 相似文献
84.
The hypothesis of Geisler (Brain Res. 212 (1981) 198-201), in which the different spontaneous-rate classes of primary auditory neurons were accounted for by the different sizes of uniquantal EPSPs relative to the gap between resting membrane and threshold potentials, was represented with an expanded model which included relative refractory effects. The spike rates generated by the expanded model, when plotted vs. estimated sound level, are qualitatively similar to those of experimentally obtained rate-level curves. The hypothesis is also consistent with recent ultrastructural data which suggest that average quantal-release rates for any particular primary auditory neuron are inversely related to its spontaneous rate. The model's recovery processes following spike generation (hazard functions) are also similar to those observed experimentally. 相似文献
85.
86.
We have analyzed the compositional properties of coding (protein encoding) and non-coding sequences of Plasmodium falciparum, a unicellular parasite characterized by an extremely AT-rich genome. GC% levels, base and dinucleotide frequencies were studied. We found that among the various factors that contribute to the properties of the sequences analyzed, the most relevant are the compositional constraints which operate on the whole genome. 相似文献
87.
JV Llau L Hoyas J Ezpeleta J García-Polit M Barberá MJ Santes 《Canadian Metallurgical Quarterly》1997,44(2):70-78
Low molecular weight heparins are a group of drugs that have only recently been introduced in clinical practice. The are widely used for prophylaxis in thromboembolic disease and are being employed increasingly to treat established venous thrombosis. One way in which these drugs are often used is for prophylaxis in the perioperative period for patients at high risk of developing venous thromboembolism, and the anesthesiologist must therefore be familiar with the main aspects of this application. We review pharmacological characteristics of these drugs as well as the literature on low molecular weight heparins, stressing points of main interest to the anesthesiologist and intensive care recovery unit specialist, namely adverse effects (mainly bleeding) and the implications that use of low molecular weight heparin will have on choice of anesthetic (in particular the dilemma of whether to use local/regional anesthesia). 相似文献
88.
89.
J Zaloudík I Kocák Z Pacovsky P Karásek V Fait H Bartonková M Nekulová 《Canadian Metallurgical Quarterly》1997,43(3):171-172
In the absence of adequate autogenous vein for tibial artery bypass in limb salvage surgery, the use of prosthetic grafts with a distal anastomotic vein cuff or patch has shown promising results. Here, we describe how the Florester Internal Vessel Occluder (Meadox UK, Bedfordshire, UK) can facilitate the construction of a distal anastomotic vein cuff. 相似文献
90.
OD de Rada AC Villaro LM Montuenga A Martínez DR Springall JM Polak 《Canadian Metallurgical Quarterly》1993,162(1-2):121-124
The presence of nitric oxide synthase (NO-synthase), the enzyme responsible for the production of nitric oxide (NO) from L-arginine, is shown immunocytochemically in the intrinsic neurons of the human and porcine respiratory tract. NO-synthase immunoreactivity is demonstrated in a subpopulation of neurons of the microganglia present in the wall of the extra- and intrapulmonary bronchi as well as in the hilar region of the lung in relation to blood vessels. The immunostaining was also found in some nerve fibers of the respiratory nervous system. Human and porcine lung gave similar results. The possible involvement of NO in the nonadrenergic noncholinergic (NANC) nervous regulation of the lung is discussed. 相似文献