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981.
982.
AIMS OF THE STUDY: To determine the risk factors for local and distant failure in node-negative breast cancer treated with breast-conservative surgery and radiotherapy and to determine the relationship between these two events. MATERIAL AND METHODS: We retrospectively selected 908 patients who received conservative surgery and radiotherapy but no chemotherapy between 1980 and 1995, for a node-negative breast cancer. Patients were divided in two groups according to the status of the margins of resection. All pathology specimens were reviewed. RESULTS: In case of negative margins, the risk factors for local recurrences picked up by the Cox model were histologic multifocality (P = 0.0076), peritumoral vessel invasion (P = 0.021) and age < or = 40 years (P = 0.024), and in case of involved margins, negative oestrogen receptors (P = 0.0012), histologic multifocality (P = 0.0028), and absence of hormonal therapy (P = 0.017). The 10-year local recurrence rate was 18% in case of negative margins and 29% in case of involved margins, although in the latter case patients received high-dose adjuvant radiotherapy. Accordingly, the 10-year distant failure rates were 16% and 27%, respectively. Many arguments suggest that local and distant failures are closely related. CONCLUSION: Patients with histologic multifocality or positive margins are at high risk of local failure and then of distant failure, and require a more aggressive initial treatment. 相似文献
983.
The dynamic nature of blood banking presents significant challenges in information acquisition, processing, and management. Blood banks have turned increasingly to computer technology for assistance with information handling. Novel applications of computer-based technology in blood banking and transfusion medicine have been developed and reported in the medical literature. This article reviews computer-based donor interviewing, expert system determination of donor eligibility based on viral marker testing results, inventory management through computer simulation analysis, prospective screening of blood orders by experts systems, and computer-based blood compatibility assessment. 相似文献
984.
985.
A semantic relatedness decision task was used to investigate whether phonological recording occurs automatically and whether it mediates lexical access in visual word recognition and reading. In this task, subjects read a pair of words and decided whether they were related or unrelated in meaning. In Experiment 1, unrelated word-homophone pairs (e.g., LION-BARE) and their visual controls (e.g., LION-BEAN) as well as related word pairs (e.g., FISH-NET) were presented. Homophone pairs were more likely to be judged as related or more slowly rejected as unrelated than their control pairs, suggesting phonological access of word meanings. In Experiment 2, word-pseudohomophone pairs (e.g., TABLE-CHARE) and their visual controls (e.g., TABLE-CHARK) as well as related and unrelated word pairs were presented. Pseudohomophone pairs were more likely to be judged as related or more slowly rejected as unrelated than their control pairs, again suggesting automatic phonological recording in reading. 相似文献
986.
OBJECTIVE: To evaluate the efficacy of unreamed retrograde intramedullary (IM) nailing of fractures of the femoral shaft in a second series of patients using modifications suggested from our initial study. DESIGN: Prospective. SETTING: Level I trauma center. METHODS: Based on the findings of a previous study, we began a clinical series incorporating changes consisting of (a) inclusion of any patient with a femoral shaft fracture amenable to IM nailing (i.e., closed physes), (b) primary use of a split patellar tendon intercondylar distal femoral entry portal, and (c) the use of a full-length femoral implant having variable size availability and dynamization capability. Over a twelve-month period, thirty-four patients with thirty-five femoral shaft fractures were treated. The protocol called for planned dynamization in statically locked stable fractures and unstable fractures showing minimal healing at six to twelve weeks. Functional outcome was assessed by using the Knee Society clinical rating system. RESULTS: Incorporating the concepts of canal fill and early dynamization, there were only two nonunions (6 percent) in this series as compared with 14 percent in the previously reported series with an overall shorter time to union (12.6 versus 15 weeks). There were no infections or malunions. Postoperative complaints of knee pain were minimal (knee score average: 98 points) and knee function was excellent (knee score average: 97 points). CONCLUSIONS: Although not advocated as a replacement for other techniques, unreamed retrograde nailing is presented as a safe and beneficial fracture fixation method that should be added to the orthopaedic surgeon's treatment armamentarium. The operative technique is quick and simple, and blood loss is minimal. Early nail dynamization and early weight-bearing are important in minimizing the risk of nonunion. 相似文献
987.
Video Respite: an innovative resource for family, professional caregivers, and persons with dementia
The development of a new and promising resource for family, professional caregivers, and persons with dementia is detailed in this article. The concept, Video Respite, refers to the initial goal of creating videotapes specifically for persons with dementia to capture and maintain their attention, enabling caregivers to have respite time. Ten 20-53-minute videotapes are described along with their potential benefits and limitations. Early research findings reveal that most persons with Alzheimer's disease (AD) watch and participate with the tapes, caregivers use the time for respite, and staff of SCU's report the tapes to be calming for the residents. 相似文献
988.
LA Schuh TR Henry G Fromes M Blaivas DA Ross I Drury 《Canadian Metallurgical Quarterly》1998,55(10):1325-1328
BACKGROUND: There is controversy in the literature regarding the importance of risk factors in developing epilepsy and seizure outcome following anterior temporal lobectomy. Some of the existing studies may be biased because of patient selection and limitations in determining predisposition. OBJECTIVE: To investigate the role of risk factors for epilepsy in determining outcome following anterior temporal lobectomy. PATIENTS AND METHODS: We identified 102 patients in a consecutive surgery series for epilepsy from a tertiary center with a minimum of 1-year postoperative follow-up. Risk factors for epilepsy were determined prospectively on at least 3 occasions before anterior temporal lobectomy. Risk factors investigated were a history of febrile convulsions, family history of epilepsy, significant head trauma, history of meningitis, history of encephalitis, or significant perinatal insult. Foreign tissue lesions on magnetic resonance imaging was also included if an anterior temporal lobectomy was performed for presumed dual pathologic findings (hippocampus and lesion). Outcome was determined using Engel's classification. For statistical analysis we used successive logistic regression analysis, chi(2) test, Fisher exact test, and t test. RESULTS: Of the 102 patients, 13 had no identified risk factor for epilepsy, 49 had 1 identified risk factor, and 40 had more than 1. Frequencies were 39 febrile convulsions (15 complex febrile convulsions), 29 head trauma, 22 with lesions seen on magnetic resonance imaging, 12 history of meningitis, 2 history of encephalitis, 19 family history of epilepsy, and 4 perinatal insult. Seventy-one (70%) were classified as Engel's class I, with 56 patients continuously free of seizures at follow-up. Those without risk factor were as likely to be rendered free of seizures following anterior temporal lobectomy as those with a risk factor (P = .27). No risk factor alone or in combination was correlated with complete freedom from seizures following anterior temporal lobectomy, but the presence of head trauma, alone or in combination, was correlated with continued seizures following anterior temporal lobectomy (P = .03; odds ratio, 2.6). Better outcomes were not seen in those with head trauma before the age of 5 years (P = .57). These findings did not change if all those with lesions on magnetic resonance imaging were excluded in the analysis. Those with a history of head trauma were as likely to have pathologic evidence of mesial temporal sclerosis as others (P = .82). CONCLUSIONS: Patients with a history of significant head trauma are less likely to become free of seizures following anterior temporal lobectomy. No other risk factor correlated with a statistically significant greater or lesser chance of freedom from seizures. This information may be used in preoperative counseling of patients. 相似文献
989.
CH Chen M Nakayama E Nevo BJ Fetics WL Maughan DA Kass 《Canadian Metallurgical Quarterly》1998,32(5):1221-1227
OBJECTIVES: We tested the hypothesis that age-related arterial stiffening is matched by ventricular systolic stiffening, and that both enhance systolic pressure sensitivity to altered cardiac preload. BACKGROUND: Arterial rigidity with age likely enhances blood pressure sensitivity to ventricular filling volume shifts. Tandem increases in ventricular systolic stiffness may also occur and could potentially enhance this sensitivity. METHODS: Invasive left ventricular pressure-volume relations were measured by conductance catheter in 57 adults aged 19 to 93 years. Patients had normal heart function and no cardiac hypertrophy and were referred for catheterization to evaluate chest pain. Twenty-eight subjects had normal coronary angiography and hemodynamics, and the remaining had either systolic hypertension or coronary artery disease without infarction. Data recorded at rest and during transient preload reduction by inferior vena caval obstruction yielded systolic and diastolic left ventricular chamber and effective arterial stiffness and pulse pressure. RESULTS: Left ventricular volumes, ejection fraction and heart rate were unaltered by age, whereas vascular load and stiffening increased (p < 0.008). Arterial stiffening (Ea) was matched by increased ventricular systolic stiffness (Ees): Ees=0.91 x Ea + 0.53, (r=0.50, p < 0.0001), maintaining arterial-heart interaction (Ea/Ees ratio) age-independent. Ventricular systolic and diastolic stiffnesses correlated (r=0.51, p < 0.0001) and increased with age (p < 0.03). Both ventricular and vascular stiffening significantly increased systolic pressure sensitivity to cardiac preload (p < 0.006). CONCLUSIONS: Arterial stiffening with age is matched by ventricular systolic stiffening even without hypertrophy. The two effects contribute to elevating systolic pressure sensitivity to altered chamber filling. In addition to recognized baroreflex and autonomic dysfunction with age, combined stiffening could further enhance pressure lability with diuretics and postural shifts in the elderly. 相似文献
990.
BM Burkhart N Li DA Langs WA Pangborn WL Duax 《Canadian Metallurgical Quarterly》1998,95(22):12950-12955
The linear pentadecapeptide antibiotic, gramicidin D, is a naturally occurring product of Bacillus brevis known to form ion channels in synthetic and natural membranes. The x-ray crystal structures of the right-handed double-stranded double-helical dimers (DSDH) reported here agree with 15N-NMR and CD data on the functional gramicidin D channel in lipid bilayers. These structures demonstrate single-file ion transfer through the channels. The results also indicate that previous crystal structure reports of a left-handed double-stranded double-helical dimer in complex with Cs+ and K+ salts may be in error and that our evidence points to the DSDH as the major conformer responsible for ion transport in membranes. 相似文献