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41.
A 34-year-old woman underwent embolization of a left paraorbital arteriovenous malformation guided with a bi-plane x-ray system in two sessions separated by 3 days. Imaging included 110 minutes of fluoroscopy and 46 digital subtraction angiography acquisitions. Entrance skin dose rates were determined with measurements performed on a skull phantom. The maximum possible skin dose was estimated to be 6.6 Gy, which is consistent with the temporary epilation in the right occipital region of the skull reported by the patient approximately 5 weeks later. 相似文献
42.
In Alberta, cellulitis condemnations average 0.5% and are among the highest in Canada. Presently, all cellulitis-affected birds are condemned for fear of systemic infections and public health implications. In a slaughterhouse sample of 102 birds condemned with cellulitis, Escherichia coli was isolated from 83.3% of the lesions. All hearts were cultured and from 11.2% E. coli was recovered. Gross lesions of perihepatitis, infected oviducts, and arthritis were found in 11.2%, 6.7%, and 2.9% of the birds, respectively. Serotyping suggested that visceral infection occurs independent of cellulitis in at least half of the cases. There was no correlation between microscopic visceral lesions and positive bacterial cultures. Two E. coli isolates of serogroup 0157 produced no toxin and neither isolate produced CS31A, F107, or F1845 fimbriae. Cellulitis lesions ranged from 0.55 to 218.9 cm2. All lesions under 16 cm2 and 64% of lesions up to 48 cm2 were considered suitable for trimming. 相似文献
43.
LS Prichep KR Alper S Kowalik H Merkin M Tom ER John MS Rosenthal 《Canadian Metallurgical Quarterly》1996,40(10):986-993
This study replicates preliminary findings reporting a quantitative electroencephalographic (QEEG) profile of crack cocaine dependence in abstinence. All subjects (n = 52) met criteria for DMS-III-R cocaine dependence (in the form of crack), and were residing in a drug-free therapeutic community. Baseline QEEG evaluations were conducted at intake (5-10 days after last use of crack, and at follow-up (1 month after last reported use). Previous findings of significant excess of relative alpha power and deficit of absolute and relative delta and theta power were replicated in this expanded group. Abnormalities were greater in anterior than posterior regions, and disturbances in interhemispheric relationships were also observed. Further, QEEG showed little change in the interval between the first and second evaluations. This QEEG profile may reflect persistent alterations in neurotransmission as a possible consequence of chronic cocaine exposure. 相似文献
44.
Apoptosis has classically been viewed as a process not involving mitochondria, whereas the implication of mitochondrial dysfunction in necrosis has been recognized for several decades. Recently, it has become clear that apoptosis implies a disruption of mitochondrial membrane intregrity that is decisive for the cell death process. Cytofluorometric methods assessing the mitochondrial membrane function and structure can be employed to demonstrate that, at least in most models of apoptosis, mitochondrial changes precede caspase and nuclease activation. Moreover, pharmacological and genetic experiments suggest that the loss of mitochondrial membrane integrity is a critical event of the apoptotic process, beyond or at the point of no return of programmed cell death. Inhibitors of the mitochondrial megachannel (= permeability transition pore) can prevent both the mitochondrial and the post-mitochondrial manifestations of apoptosis. 相似文献
45.
D Chassard M Guiraud J Gauthier P Gelas KR Berrada P Bouletreau 《Canadian Metallurgical Quarterly》1994,22(2):248-251
OBJECTIVE: In mechanically ventilated patients, pulmonary gas exchange was investigated during the administration of total parenteral nutrition containing medium-chain triglycerides or long-chain triglycerides as fat emulsions. DESIGN: Prospective, randomized, crossover trial (two lipid infusion periods of 8 hrs). SETTING: Intensive care unit in a university hospital. PATIENTS: Six mechanically ventilated patients, using the pressure-support mode. INTERVENTIONS: Total caloric intake was adapted according to measured energy expenditure. Fat emulsion provided 50% of the energy expenditure. Patients were infused with 50% medium-chain/50% long-chain triglycerides or 100% long-chain triglycerides in a random sequence. MEASUREMENTS AND MAIN RESULTS: Oxygen consumption, CO2 production, and minute ventilation were measured by indirect calorimetry. PaO2 and PaCO2 were determined in blood samples. Medium-chain triglycerides increased oxygen consumption by 27.8% and minute ventilation by 14.3% at the end of the protocol. CO2 production, PaO2, and PaCO2 were not different between groups. CONCLUSIONS: Medium-chain triglycerides cause an increase in metabolic demand in mechanically ventilated patients when they are infused over a short period. Postoperative or intensive care unit patients with a low pulmonary reserve should receive infusions of medium-chain triglycerides over a more prolonged period than long-chain triglycerides. 相似文献
46.
KR Ward 《Canadian Metallurgical Quarterly》1994,1(5):482-489
OBJECTIVE: To propose reasons for the variability of the hemodynamic responses and survival data observed when interposed abdominal compression cardiopulmonary resuscitation (IAC-CPR) is performed on humans in cardiac arrest. METHODS: Critical content review of all studies performed in the United States examining IAC-CPR in humans and of selected animal studies addressing hemodynamic mechanisms of CPR. Articles in the English language dealing with human IAC-CPR studies from 1970-1993 were retrieved using the MEDLINE database of the National Library of Medicine. RESULTS: IAC-CPR does not consistently improve coronary perfusion pressure (CPP) over standard CPR in humans and is capable of decreasing as well as increasing CPP. This variability does not seem dependent on the manner in which abdominal compressions are performed. Because of the limited response to standard CPR, significant increases in return of spontaneous circulation would be expected with IAC-CPR if a large percentage of patients were to have favorable increases in CPP. However, other patients may be adversely affected by decreases in CPP during IAC-CPR, with unsuccessful resuscitation of those individuals. Return of spontaneous circulation also may be enhanced using IAC-CPR due to other factors reflected in the initial arrest rhythm and in arrest-population demographics. CONCLUSION: IAC-CPR should not be recommended for routine use until the mechanism of its beneficial effects is known and until those patients who are likely to benefit from the technique can be better identified. 相似文献
47.
OBJECTIVE: The aim of this study was to determine if omeprazole improves pulmonary function and quality of life in asthmatics with gastroesophageal reflux. METHODS: This was a double blind, randomized, placebo-controlled cross-over trial. After a 4-wk lead-in period, nine patients with documented asthma and gastroesophageal reflux, were prescribed either omeprazole 20 mg, daily or placebo for 8 wk and then crossed over to the alternate treatment. Outcome measurements included: forced expiratory volume at 1 s (FEV1), peak expiratory flow rate (PEFR), and responses on the Asthma Quality of Life Questionnaire, a validated disease specific measure of functional status. RESULTS: After omeprazole treatment, compared with placebo, patients had higher mean morning and evening PEFR, mean absolute difference (95% CI): morning: 37.8 L/min. (10.9-64.6), evening: 31.2 (3.2-59.2). Omeprazole treatment led to higher mean overall scores on the Asthma Quality of Life Questionnaire, and on the subdomains of activity limitation, symptoms, and emotions (p = 0.039, 0.049, 0.024, 0.040). A trend toward higher FEV1 (mean: 15.6% difference) with omeprazole failed to reach statistical significance (p > 0.2). CONCLUSIONS: After taking omeprazole for 8 wk, asthmatics with GER have better PEFR and quality of life than after placebo. 相似文献
48.
We report the case of a 77-year-old man admitted nine days after being commenced on azathioprine with symptoms initially thought to be secondary to sepsis but in fact due to azathioprine hypersensitivity. He developed histologically proven cutaneous leucocytoclastic vasculitis following the re-introduction of azathioprine. We review the literature concerning adverse reactions to azathioprine and the problems of making the diagnosis as well as highlighting azathioprine as a novel cause of leucocytoclastic vasculitis. 相似文献
49.
50.
KR Romines JK Morris WJ Howe PK Tomich MM Horng KT Chong RR Hinshaw DJ Anderson JW Strohbach SR Turner SA Mizsak 《Canadian Metallurgical Quarterly》1996,39(20):4125-4130
Previously, 3-substituted cycloalkylpyranones, such as 2d, have proven to be effective inhibitors of HIV protease. In an initial series of 3-(1-phenylpropyl) derivatives with various cycloalkyl ring sizes, the cyclooctyl analog was the most potent. We became interested in exploring the influence of other structural changes, such as substitution on the phenyl ring and saturation of the 5,6-double bond, on the cycloalkyl ring size structure-activity relationship (SAR). Saturation of the 5,6-double bond in the pyrone ring significantly impacts the SAR, altering the optimal ring size from eight to six. Substitution of a sulfonamide at the meta position of the phenyl ring dramatically increases the potency of these inhibitors, but it does not change the optimal ring size in either the cycloalkylpyranone or the cycloalkyldihydropyrone series. This work has led to the identification of compounds with superb binding affinity for the HIV protease (Ki values in the 10-50 pM range). In addition, the cycloalkyldihydropyrones showed excellent antiviral activity in cell culture, with ED50 values as low as 1 microM. 相似文献