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991.
992.
IV Volkova IR Losev VA Lemenkov AG Mushegov SV Mogil'nikov 《Canadian Metallurgical Quarterly》1996,(3):8-12
The paper describes a non-invasive oscillometric blood pressure (BP) measuring device. It provides an algorithm for the automatic measurement of systolic and diastolic BP values. A variant of assessing the BP measurement stability is proposed and the results of this assessment are given for 3 devices made by different firms. The total errors made by the studied device that functions as part of a physician's computer monitor are defined. Health institutions, resuscitation units, operating rooms for children and adults are an application sphere of the device. 相似文献
993.
AR Localio SL Weaver JR Landis AG Lawthers TA Brenhan L Hebert TJ Sharp 《Canadian Metallurgical Quarterly》1996,125(6):457-464
Forty critically ill adult patients with severe Gram-negative infection were treated with once-daily amikacin combined with ceftazidime. The mean age was 56.6 +/- 19 years and mean APACHE II score was 22.7 +/- 6.6. Forty percent of patients required mechanical ventilation. The mean creatinine clearance at onset of therapy was 59.4 +/- 28 ml/min. All bacterial isolates were sensitive to amikacin. Fixed doses of amikacin 15 mg/kg, 12 mg/kg, and 8 mg/kg body weight were given once daily to patients with estimated creatinine clearance of > 80 ml/min., 50-80 ml/min., and < 50 ml/min, respectively. Forty-two causative gram-negative bacteria were isolated from 40 patients. The most common bacteria were Pseudomonas aeruginosa (18), and Escherichia coli (10). Overall clinical success and bacteriological eradication occurred in 85% and 87.5% of patients; 78.9% and 79% of patients with hospital-acquired infections; 90.5% and 95.2% of patients with community-acquired infections; and 62.5% and 81.3% of patients requiring mechanical ventilation, respectively. Therapeutic failure was documented in 15% of patients. Death due to infection was scored in two patients. The remaining were all due to persistence of the initial causative bacteria in patients with hospital-acquired infections. Persistence was documented with Ps. aeruginosa (2), Serratia spp. (1), and Acinetobacter spp. (1). Overall mortality occurred in 22.5% patients. Death unrelated to infection occurred in 7 patients. There was no clinical evidence of ototoxicity in any of our patients, however, nephrotoxicity was documented in 5%. In conclusion, once-daily amikacin combined with ceftazidime is practical, efficacious and probably safe in critically ill infected patients. 相似文献
994.
AL Cherniaev OM Grobova GV Nekliudova AG Chuchalin SP Ammosova PG Pleshanov OA Liaskina VP Chernikov 《Canadian Metallurgical Quarterly》1998,60(5):36-41
Tuberculosis is an ancient disease which has had a resurgence in the United States. Many elderly clients were exposed to tuberculosis as children and young adults and are still carrying the infection today. This article describes tuberculosis as it affects the elderly client in community and nursing home settings. The history, etiology, clinical manifestations, treatment, and prevention of tuberculosis infection and disease are presented. Because nurses can be very instrumental in controlling tuberculosis in the elderly, gerontological nursing implications are discussed. 相似文献
995.
P Spencer CM Cobb DM Wieliczka AG Glaros PJ Morris 《Canadian Metallurgical Quarterly》1998,69(11):1278-1282
In tissues that closely approximate bone, sufficient heat may be transferred to the bone during laser surgery to cause damage and/or necrosis. To date, there have been few studies examining the temperatures elicited at the bone surface as a result of laser application to the overlying soft tissues. The purpose of this investigation was to determine, under in vitro conditions, temperature changes at the bone/soft tissue interface during laser ablation with CO2 and Nd:YAG lasers used with and without (w/wo) air/water coolant. Experimental specimens consisted of 5 mandibles from freshly sacrificed hogs; laser treatment sites were the buccal and lingual attached gingiva of the molars and the lingual keratinized mucosa of the incisor region. CO2 and Nd:YAG lasers were used w/wo coolant at power settings of 4 to 8 W and 5 to 9 W, respectively. Temperature changes were measured with a copper constant thermocouple contained within a 21 gauge hypodermic needle. In comparing the lasers at comparable energy densities w/wo coolant, temperature increases at the bone/soft tissue interface ranged from 8.0 to 11.1 degrees C with the Nd:YAG and 1.4 to 2.1 degrees C with the CO2. Similarly, in comparing the times required for the interface to return to baseline temperature following removal of the laser, values ranged from approximately 143 to 205 and approximately 119 to 139 seconds for the Nd:YAG and CO2, respectively. Results from this study suggest that, at energy densities equal or above those reported here, the increase in temperature at the bone surface as a result of periodontal soft tissue surgery with the Nd:YAG laser could be damaging, especially if the exposure is prolonged. 相似文献
996.
G d'Albasio F Pacini E Camarri A Messori G Trallori AG Bonanomi G Bardazzi M Milla S Ferrero M Biagini S Quaranta A Amorosi 《Canadian Metallurgical Quarterly》1997,92(7):1143-1147
OBJECTIVES: To assess the efficacy of a combination of oral and topical 5-aminosalicylic acid (5-ASA) for the maintenance treatment of ulcerative colitis, we undertook a double-blind randomized clinical trial. METHODS: Patients aged 18 to 65 yr (with disease extent greater than proctitis only) were eligible for inclusion in the study if they met the following criteria: (a) history of two or more relapses in the last year; (b) achievement of remission in the last 3 months (with maintenance of remission for at least 1 month). Patients enrolled in the study were randomly assigned to one of the two following 1-yr treatments: (1) combined therapy with 5-ASA tablets 1.6 g/day and 5-ASA enemas 4 g/100 ml twice weekly; (2) oral therapy with 5-ASA tablets 1.6 g/day and placebo enemas/twice weekly. The main end point of the study was the maintenance of remission at 12 months. RESULTS: Upon completion of the study, relapse occurred in 13 of 33 patients in the combined treatment group versus 23 of 36 patients in the oral treatment group (39 vs 69%; p = 0.036). No significant side effects related to treatment were observed in either group. A simplified pharmacoeconomic analysis shows that this form of combined treatment can have a favorable cost-effectiveness ratio. CONCLUSIONS: Our results indicate that 5-ASA given daily by oral route and intermittently by topical route can be more effective than oral therapy alone. This form of combination treatment can be appropriate for patients at high risk of relapse. 相似文献
997.
M Griffioen WT Steegenga IJ Ouwerkerk LT Peltenburg AG Jochemsen PI Schrier 《Canadian Metallurgical Quarterly》1998,35(13):829-835
Major Histocompatibility Complex (MHC, HLA in humans) class I antigens play an important role in cellular immunology by presenting antigens to T cells. Downregulation of MHC class I expression is thought to be a mechanism by which tumor cells escape from T cell-mediated lysis. In primary human melanomas and melanoma cell lines, HLA-B expression is frequently downmodulated, correlating with elevated expression of the c-myc oncogene. Transfection experiments have shown that c-myc induces HLA-B downregulation through a -68 to +13 base pairs (bp) core promoter fragment, containing CCAAT and TATA-like (TCTA) boxes. Since (i) c-myc has been reported to activate the human p53 promoter and (ii) p53 is capable of repressing a large array of basal promoters, we investigated whether c-myc-induced HLA-B abrogation is mediated by p53. In this article, it is shown that the HLA-B core promoter is indeed repressed by wild-type p53, making p53 a candidate for mediating c-myc-induced HLA-B downregulation. However, transfection of c-myc into p53-null cell lines still resulted in suppression of the basal HLA-B promoter, demonstrating that c-myc and p53 repress the minimal HLA-B promoter through independent mechanisms. 相似文献
998.
A Vicente A Varas RS Acedón E Jiménez JJ Mu?oz AG Zapata 《Canadian Metallurgical Quarterly》1998,5(4):319-331
This study measured the release of glutamate (Glu) and aspartate (Asp) amino acid transmitters in the ventrocaudal compartment of the rat periaqueductal gray (PAG) following exposure to unilateral peripheral inflammation. The release of endogenous Glu and Asp from the rat ventrocaudal PAG was monitored with the microdialysis technique in unanesthetized, unrestrained rats. There was significant increase (1,300%) in the basal concentrations of Glu release in the 7 days Complete Freund's Adjuvant (CFA) treated group compared to 24 h mineral oil control group. Amino acid release was induced by infusing veratridine (75 microM, a sodium channel activator) directly through the 1 mm long dialysis probe. Perfusion of veratridine into the ventrocaudal PAG resulted in significant elevation of Glu and Asp amino acids. In the 24 h and 7 days CFA treated rats, veratridine-evoked release of Glu was significantly decreased in the lateral ventrocaudal PAG compared to control rats injected with mineral oil (CFA vehicle). The peak minus baseline concentrations of Glu in 24 h and 7 days CFA treated groups decreased 55.7% and 43.9%, respectively. In contrast, The basal and the peak minus baseline concentrations of Asp showed no significant change between control group and 24 h and 7 days CFA treated animals. The results provide direct evidence that Glu excitatory amino acid may be involved in nociception/nociception modulation pathway in the ventrocaudal PAG. 相似文献
999.
AG Hadjipavlou JW Simmons JP Yang LX Bi DJ Simmons JT Necessary 《Canadian Metallurgical Quarterly》1998,11(4):318-321
An ornamental pet fish was diagnosed with a spinal fracture and subluxation involving truncal vertebrae 5 and 6 (T5-T6) using conventional radiography, nuclear scintigraphy, and computed tomography. Attempts to evaluate the dynamic nature of the lesion using conventional fluoroscopy in the unanesthetized, moving patient were unsuccessful. Adaptation of imaging techniques to accommodate a fish patient was not difficult and diagnostic images were obtained. The use of multiple imaging techniques was useful in the diagnosis and determination of the treatment plan of the spinal fracture in this patient. 相似文献
1000.
AG Schoofs FC Odds R Colebunders M Ieven H Goossens 《Canadian Metallurgical Quarterly》1998,41(5-6):203-211
The Candida species isolated from oral rinses of 130 human immunodeficiency virus (HIV) infected patients were compared with those of 130 healthy non-matched volunteers. The oral rinses were plated on CHROMagar Candida medium (CAC) and on CAC supplemented with 10 micrograms (CF10) and 100 micrograms (CF100) of fluconazole per ml. The prevalence of non-albicans Candida spp. in oral rinses of HIV-infected patients and their correlation with the clinical and epidemiological characteristics of the patients were studied. Susceptibility of the Candida spp. isolated was determined by a microbroth dilution method based on the NCCLS reference procedure. Results of susceptibility tests of the yeast isolates were compared with their growth at the time of isolation on CAC supplemented with fluconazole. Thirty-five (30.7%) strains of non-albicans Candida spp. were isolated from the HIV-positive population, vs. seven (15.9%) from the immunocompetent population. Growth on CF10 correlated in 96% of the cases with fluconazole minimum inhibitory concentration (MIC) > 8 micrograms ml-1. Smoking and use of azoles were significantly associated with oral carriage of non-albicans Candida spp. (P < 0.05). The prevalence of non-albicans Candida spp. in HIV-positive persons in oral rinse samples is twice as high as in the HIV-negative population. Smoking and treatment with azoles are risk factors for the oral carriage of non-albicans Candida spp. The isolation of yeasts on CAC plates supplemented with fluconazole allows combination of presumptive yeast identification and fluconazole susceptibility testing. 相似文献