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991.
S Pagni EA Ulfe WD Montgomery DJ VanHimbergen DJ Fisher LA Gray PA Spence 《Canadian Metallurgical Quarterly》1998,66(5):1626-1631
BACKGROUND: Leg wound complications after saphenectomy are frequent after coronary bypass operations and have a detrimental effect on postoperative quality of life and treatment cost. To reduce morbidity, we evaluated a new technique of video-assisted vein harvest. METHODS: Between March 1996 and October 1996, 50 patients had video-assisted saphenectomy (VAS) and 40 patients had the standard open technique (control group). An additional 13 patients had both procedures (hybrid group). Level of pain, edema, and wound complications were evaluated at discharge and at 2, 4, and 6 weeks postoperatively. RESULTS: The mean operating time for VAS patients was slightly higher than for control (60.6+/-24.7 minutes versus 53.2+/-21.1 minutes; p > 0.05). The average incision length in VAS patients was 13.8+/-8.8 cm for an average of 3.3 grafts per patient. Three VAS procedures were aborted, two because of time constraints, and one because of bleeding, and a segment of vein was lost to injury. The VAS group had considerably less early postoperative pain than the control group (1.7+/-1.2 versus 4.1+/-1.4 [1 = mild, 10 = severe]; p < 0.005) and edema was similar for both groups. Patients in the hybrid group reported less pain in the VAS-operated leg. Serious wound infection occurred in 4 patients, with 2 patients in the control group requiring reoperation for drainage and flap reconstruction. CONCLUSIONS: Based on this initial experience, VAS harvesting, although initially more time consuming, is a rapidly mastered technique, results in shorter overall incision length, and is associated with considerably less postoperative pain than the standard open technique. 相似文献
992.
A Voss YH van Zwam JF Meis W Melchers EA Steegers 《Canadian Metallurgical Quarterly》1998,76(1):71-73
We report on partial dup(22q), growth deficiency, and the facioauriculovertebral sequence including hemifacial microsomia, cleft lip and palate, preauricular tags, and hearing loss in one patient. No endocrine or systemic cause for growth deficiency was identified. The case illustrates applicability of chromosome analysis in syndrome-associated growth failure, and a previously unreported associated chromosome abnormality. 相似文献
993.
EA Galliven A Singh D Michelson S Bina PW Gold PA Deuster 《Canadian Metallurgical Quarterly》1997,83(6):1822-1831
Two studies, each utilizing short-term treadmill exercise of a different intensity, assessed the metabolic and hormonal responses of women to exercise in the morning (AM) and late afternoon (PM). In study 1, plasma concentrations of growth hormone, arginine vasopressin, catecholamines, adrenocorticotropic hormone, cortisol, lactate, and glucose were measured before, during, and after high-intensity exercise (90% maximal O2 uptake) in the AM and PM. In study 2, plasma concentrations of adrenocorticotropic hormone, cortisol, lactate, and glucose were measured before, during, and after moderate-intensity exercise (70% maximal O2 uptake) in the AM and PM in the follicular (days 3-9), midcycle (days 10-16), and luteal (days 18-26) phases of the menstrual cycle. The results of studies 1 and 2 revealed no significant diurnal differences in the magnitude of responses for any measured variable. In addition, study 2 revealed a significant time-by-phase interaction for glucose (P = 0. 014). However, net integrated responses were similar across cycle phases. These data suggest that metabolic and hormonal responses to short-term, high-intensity exercise can be assessed with equal reliability in the AM and PM and that there are subtle differences in blood glucose responses to moderate-intensity exercise across menstrual cycle phase. 相似文献
994.
N Gnanadesigan EA Pechter L Mascola 《Canadian Metallurgical Quarterly》1994,94(3):531-3; discussion 534-5
A case of breast implant infection with L. monocytogenes is presented. The nature of this organism, its usual mode of transmission, and factors predisposing to the development of listeriosis are reviewed. We speculate that, in this case, the organism was acquired during a natural period of depressed immunity due to pregnancy, and it initiated a low-grade infection around the breast prosthesis. Possible implications of this scenario are discussed. 相似文献
995.
Extracellular nucleotides achieve their role as cell-to-cell communicators by acting at cell surface transmembrane receptors-the P2 receptors. Before molecular cloning led to the isolation of any P2-receptor sequence, a small number of receptor types had been proposed on the basis of pharmacological evidence. The application of molecular biology to this field of receptor research has indicated that a great underestimation of the number of receptor subtypes and of their abundance had occurred. There are now known to be seven characterized P2Y (G protein linked) receptors and the same number again of P2X receptors of the transmitter-gated ion channel type. In this review, we discuss the properties of these cloned receptors, their distribution within the nervous system, and their methods of signal transduction. 相似文献
996.
This article specifically addressed the need for a multidimensional approach to measuring adolescents' drug involvement. The Drug Involvement Scale for Adolescents (DISA) was theoretically specified and its measurement properties were tested using Confirmatory Factor Analyses and traditional procedures with 705 high-risk and typical high school students. Five first-order dimensions, Drug Access, Alcohol Use, Other Drug Use, Drug Use Control Problems and Adverse Drug Use Consequences, and a hierarchical model of Drug Involvement demonstrated a good fit between model and data. Further, the DISA demonstrated good internal consistency (alpha = .91); correlated as expected with known correlates of adolescent drug use; discriminated drug involvement between high-risk and typical high school students; and predicted later drug involvement and known drug-related consequences among adolescents. The results suggest the DISA should be useful for capturing a multidimensional view of adolescent drug involvement in both etiologic and prevention studies. A major advantage of the DISA is its brevity: twenty-two indicators constructed from twenty-nine items. 相似文献
997.
IV Filiushkin AN Ignatov MV Leshchenko OM Makashina VS Kashirin AV Stetsenko MA Gruden'' EA Shumova AN Bel''chenko 《Canadian Metallurgical Quarterly》1998,38(1):15-26
About a decade ago the introduction of predictive testing for Huntington's disease (HD) was an important milestone in medical history. The aim of the present paper concerning predictive DNA-testing for HD is fourfold. First of all it describes the professional challenge of elaborating an adequate test protocol and of permanently using a multidisciplinary approach to deal with predictive test requests. Secondly the paper is aimed at unraveling the factors that play a part in uptake and decision making regarding predictive testing. Hereby the Health Belief Model is used as a framework for understanding differences between tested and untested persons. Thirdly the impact of the test result on psychological well-being is reviewed. Finally this paper assesses the utilisation of prenatal diagnosis after predictive testing for HD and reflects on the psychological and ethical implications of different types of prenatal tests, including preimplantation genetic diagnosis. 相似文献
998.
EA Hooker S Hagan R Coleman MF Heine P Greenwood 《Canadian Metallurgical Quarterly》1996,3(6):586-589
OBJECTIVES: To compare initial success rates of blind nasotracheal intubation using directional-tip endotracheal tubes vs standard endotracheal tubes. METHODS: A prospective trial comparing directional-tip and standard endotracheal tubes during initial attempts at blind nasotracheal intubation (BNTI) at a university hospital ED. Using an alternating schedule, the directional-tip or standard tube was used for the first attempt at BNT1. An attempt was defined as beginning when the tube was placed through the nose into the posterior pharynx and ending when the patient was intubated or the tube was removed from the nares. After the intubation, the physician graded the difficulty of the technique (i.e., easy/routine, intermediate, difficult, or unable to intubate nasally). RESULTS: There were 49 patients entered over 5 months. Patient presentations for the intubations were trauma (45.8%), overdose (33.3%), respiratory/cardiac event (12.5%), seizure (2.1%), and other (6.3%). Intubation was successful on the first attempt in 18 of 21 patients (86%; 95% CI, 64% to 97%) for the directional-tip tube vs 16 of 28 patients (57%; 95% CI, 37% to 76%) for the standard tube (p = 0.03). The groups did not differ in age, sex, clinical presentation, or perceived difficulty of intubation. Only 1 patient could not be intubated nasally and was subsequently intubated orally. CONCLUSION: The use of directional-tip tubes may improve the success rate of the first attempt at BNTI. 相似文献
999.
Experiments were conducted to elucidate the role of the cholinergic neurotransmitter system in arousal and the orienting of attention to peripheral targets. Rhesus monkeys and humans fixated a visual stimulus and responded to the onset of visual targets presented randomly in two visual field locations. The target was preceded by a valid cue (cue and target at the same location), an invalid cue (cue and target to opposite locations), a double cue (cues to both spatial locations, target to one), or, the cue was omitted (no-cue, target to either location). Reaction times (RTs) to the onset of the target were recorded. For monkeys, systemic injections of nicotine (0.003-0.012 mg/kg) or atropine (0.001-0.01 mg/kg), but not saline control injections, reduced mean RTs for all trials, indicating general behavioral stimulation. In addition, nicotine significantly reduced RTs for invalid trials but had little additional effect on those for valid, double, or no-cue trials. Virtually identical effects were observed for human chronic tobacco smokers in performing the same task following cigarette smoking. Injections of atropine in monkeys had no effect on RTs for valid or invalid trials but significantly slowed RTs in double-cue trials that did not require the orienting of attention. These results suggest that in both species, the nicotinic cholinergic system may play a role in automatic sensory orienting. In addition, the muscarinic system may play a role in alerting to visual stimuli in monkeys. 相似文献
1000.
OBJECTIVE: The purpose of this study was to determine the effects of phosphate-buffered saline (PBS), sterile tap water, normal saline, and Ringer's lactate on wound healing in an in vitro model. STUDY DESIGN: The effects of PBS, sterile tap water, normal saline, and Ringer's lactate on a primary line of canine embryonic fibroblasts were determined. ANIMALS OR SAMPLE POPULATION: A primary line of canine embryonic fibroblasts. METHODS: The effects of the various lavage solutions were determined by (1) vital staining of the treated cells with a 0.5% trypan blue solution, (2) evaluation of the amount of lactate dehydrogenase released by the treated cells, and (3) cytopathologic evaluation of hematoxylin and eosin-stained monolayers of treated canine fibroblasts. The cells were exposed to the lavage treatments for the following time intervals: 0.5 minute, 1 minute, 2.5 minutes, 5 minutes, and 10 minutes. PBS was used as the control. RESULTS: Sterile tap water significantly damaged canine fibroblasts at all time intervals (P = .05). This was attributed to the alkaline pH, hypotonicity, and presence of numerous cytotoxic trace elements in the tap water used. Cytotoxic effects were noted in fibroblasts after 10 minutes' exposure to normal saline; this may be because of the acidic pH of normal saline and lack of a buffering system. Ringer's lactate did not induce any significant fibroblast injury. CONCLUSIONS: PBS and Ringer's lactate do not induce any significant fibroblast injury, whereas normal saline and sterile tap water cause mild and severe cytotoxic effects in vitro. CLINICAL RELEVANCE: Further clinical investigation is indicated to establish whether Ringer's lactate is the wound lavage solution of choice compared with normal saline. Sterile tap water may cause considerable fibroblast injury. 相似文献