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81.
82.
SG Ellis H Tamai M Nobuyoshi K Kosuga A Colombo DR Holmes C Macaya CL Grines PL Whitlow HJ White J Moses PS Teirstein PW Serruys JA Bittl MR Mooney TM Shimshak PC Block R Erbel 《Canadian Metallurgical Quarterly》1997,96(11):3867-3872
BACKGROUND: Coronary artery bypass surgery (CABG) has been considered the therapy of choice for patients with unprotected left main (ULMT) coronary stenoses. Selected single-center reports suggest that the results of percutaneous intervention may now approach those of CABG. METHODS AND RESULTS: To assess the results of percutaneous ULMT treatment from a wide variety of experienced interventional centers, we requested data on consecutive patients treated after January 1, 1994, from 25 centers. One hundred seven patients were identified who were treated either electively (n=91) or for acute myocardial infarction (n=16). Of patients treated electively, 25% were considered inoperable, and 27% were considered high risk for bypass surgery. Primary treatment included stents (50%), directional atherectomy (24%), and balloon angioplasty (20%). Follow-up was 98.8% complete at 15+/-8 months. Results varied considerably, depending on presentation and treatment. For patients with acute myocardial infarction, technical success was achieved in 75%, and survival to hospital discharge was 31%. For elective patients, technical success was achieved in 98.9%, and in-hospital survival was strongly correlated with left ventricular ejection fraction (P=.003). Longer-term event (death, infarction, or bypass surgery) -free survival was correlated with ejection fraction (P<.001) and was inversely related to presentation with progressive or rest angina (P<.001). Surgical candidates with ejection fractions > or = 40% had an in-hospital survival of 98% and a 9-month event-free survival of 86+/-5%, whereas patients with ejection fractions < 40% had 67% and 22+/-12% in-hospital and 9-month event-free survivals, respectively. Nine hospital survivors (10.6%) experienced cardiac death within 6 months of hospital discharge. CONCLUSIONS: While results for selected patients appear promising, until early post-hospital discharge cardiac death can be better understood and minimized, percutaneous revascularization of ULMT stenosis should not be considered an alternative to bypass surgery for most patients. When percutaneous revascularization of ULMT is required, directional atherectomy and stenting appear to be the preferred techniques, and follow-up angiography 6 to 8 weeks after treatment is probably advisable. 相似文献
83.
The rate of breakdown of food in mastication depends on the ratio of two mechanical properties of the food--the toughness and modulus of elasticity (Agrawal et al., 1997)--a result which can be predicted by an analysis of the energetics of fracture. The work input to produce food fragmentation is provided by the masticatory muscles, the activity levels of which depend on sensory feedback from the mouth. Here, we test the hypothesis that the activity of a representative of this musculature is modulated by the above combination of food properties. The surface electrical activity (EMG) of the anterior temporalis muscles of ten human subjects was recorded while subjects chewed standardized volumes of 15 food types. The integrated EMG in these muscles was highly significantly related to the square root of the ratio of the above two food properties. Significant correlations were found between this food property index and integrated EMG, both when data for all chews and all subjects were lumped together (r = -0.86; p < 0.0001) and when correlation coefficients between the index and EMG were plotted for each chew made by each subject. Except for two subjects in the first chew, these coefficients reached and maintained highly significant levels throughout the masticatory sequence. Thus, a clear relationship between the electrical activity of a jaw-closing muscle and the mechanical properties of food has been found for the first time. 相似文献
84.
G Johnson PW Burvill CS Anderson K Jamrozik EG Stewart-Wynne TM Chakera 《Canadian Metallurgical Quarterly》1995,91(4):252-257
Evaluation of the relative efficacy of three screening instruments for depression and anxiety in a group of stroke patients was undertaken as part of the Perth community stroke study. Data are presented on the sensitivity and specificity of the Hospital Anxiety and Depression Scale (HAPS), the Geriatric Depression Scale and the General Health Questionnaire (GHQ) (28-item version) in screening patients 4 months after stroke for depressive and anxiety disorders diagnosed according to DSM-III criteria. The GHQ-28 and GDS but not the HADS depression, were shown to be satisfactory screening instruments for depression, with the GHQ-28 having an overall superiority. The performance of all 3 scales for screening post-stroke anxiety disorders was less satisfactory. The HADS anxiety had the best level of sensitivity, but the specificity and positive predictive values were low and the misclassification rate high. 相似文献
85.
8E5 is a chronically human immunodeficiency virus (HIV)-infected human T cell line, which we have previously shown to be extremely susceptible to hydrogen peroxide (H2O2)-induced apoptosis due to a HIV-associated catalase deficiency. Here we report that HIV gene expression additionally renders 8E5 cells 10-fold more sensitive than either uninfected A3.01 cells or HIV-infected but nonexpressing 8E5L cells to killing by 15-hydroperoxyeicosatetraenoic acid (15-HPETE), as well as several other hydroperoxy fatty acids. Whereas the viability of A3.01 and 8E5L cells was relatively unaffected by exposure to 10 microM 15-HPETE, similarly treated 8E5 cells underwent apoptosis, as demonstrated by morphological changes and the presence of fragmented DNA. The unique susceptibility of 8E5 cells was attributable to their inability to convert 15-HPETE to 15-hydroxy-eicosatetraenoic acid (15-HETE) owing to a marked reduction in glutathione peroxidase activity. Since oxidized lipids have been reported to accumulate in oxidatively stressed, HIV-infected individuals, a HIV-associated glutathione peroxidase deficiency may contribute to the depletion of CD4 T cells that occurs in the acquired immune deficiency syndrome (AIDS). 相似文献
86.
In this report we demonstrate the utility of an monoclonal antibody inhibition enzyme-linked immunosorbent assay based on the Mycobacterium leprae 35-kDa protein, purified from the rapidly growing host Mycobacterium smegmatis, for the serodiagnosis of multibacillary leprosy. The assay proved highly specific (97.5%) and sensitive (90%) and compared favorably with two other established methods routinely utilized for leprosy serodiagnosis. 相似文献
87.
AR Miller PW Pisters JE Lee NA Janjan JL Abbruzzese DB Evans 《Canadian Metallurgical Quarterly》1998,45(21):624-633
The goal of multimodality therapy for localized pancreatic cancer is to maximize local-regional disease control and patient survival. In contrast to surgery for other solid tumors, prolonged recovery following pancreaticoduodenectomy may prevent the timely delivery of postoperative adjuvant therapy. Therefore, efforts at The University of Texas, M.D. Anderson Cancer Center have focused on the delivery of chemotherapy and radiation therapy prior to surgery in patients with localized pancreatic cancer. Clinical trials have emphasized the use of altered-fractionation schedules of radiation therapy combined with novel radiation-sensitizing agents. All treatment schemes aim to decrease toxicity and treatment time while improving therapeutic efficacy. 相似文献
88.
Annular epidermolytic ichthyosis is a distinct phenotypic variant of bullous congenital ichthyosiform erythroderma that has recently been described in two separate kindreds. Individuals with this variant present with bullous ichthyosis in early childhood and hyperkeratotic lichenified plaques in the flexural areas and extensor surfaces at later ages. Characteristically, they also develop intermittent bouts of annular and polycyclic, erythematous, scaly plaques on the trunk and proximal extremities. We now describe a third kindred with annular epidermolytic ichthyosis. Molecular analysis of this family revealed a novel mutation resulting in an isoleucine to threonine substitution at residue 107 (codon 446) within the highly conserved helix termination motif at the end of the rod domain of keratin 10. 相似文献
89.
Non-accidental head injury, be it shaking, impact(s) or a combination of the two, is characterised by subdural and/or subarachnoid haemorrhages with retinal haemorrhages, but minimal or absent external cranio-facial trauma. The classical assault scenario depicts the infant being gripped around the head, face, chest and abdomen and shaken or being gripped by a limb and swung. This gripping might be expected to leave physical evidence in the form of bruising. A study was undertaken to establish the prevalence, distribution and pathological association of external bruising in 24 cases of fatal non-accidental head injury in children. At autopsy, 17 cases had new external bruises, 15 old external bruises and 13, a combination of both. However, seven (29%) cases showed no fresh external bruising and five (21%) showed no external bruising at all. Thus, external bruising may be absent in children with fatal intracranial injury. The face was shown to be the commonest site of bruising followed by the forehead and buttocks. Limb, chest and abdominal bruising were found to be uncommon. Retinal haemorrhages were confirmed in 23 (96%) cases. It is hypothesised that bruising, when present, may be a result of abuse in the form of punches and slaps rather than due to gripping during the assault. We discuss why gripping does not necessarily result in external bruising. 相似文献
90.
A case of an isolated frontal sinus fracture, reduced, fixed with miniplates and screws, and using the endoscopic technique, was presented. This case demonstrates the safety, efficacy, and economy of the endoscopic technique in properly selected cases that do not involve posterior table fractures or injury to the nasofrontal duct. The technique avoids the use of general anesthesia and the potential morbidities of coronal flaps. 相似文献