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Summary We enrolled children with acute lymphoblastic leukemia (ALL) in a Pediatric Oncology Group (POG) pilot study to monitor erythrocyte (RBC) methotrexate (MTX) and folate (F) levels before and during treatment. The mean value for RBCF at diagnosis was 0.86±0.46 nmol/ml RBC in the 214 patients who achieved remission and 1.21±0.74 nmol/ml RBC in the 10 patients who did not (P=0.020). Folate levels tended to increase during remission induction, but they dropped following an intensive consolidation with methotrexate to levels that were sustained throughout chemotherapy treatment. Methotrexate levels reached mean values of approximately 0.15 nmol/ml RBC at the end of an intensive methotrexate consolidation, then fell to levels that were sustained throughout maintenance therapy. There was a weak correlation between improved event-free survival and higher RBCMTX levels after consolidation, but no correlation was found between improved survival and the level of RBCMTX or RBCF during maintenance therapy. A larger study with more complete data is needed to determine whether RBCMTX or RBCF might be useful in predicting event-free survival in patients with ALL.This work was supported in part by grants from the National Cancer Institute and the National Institute of Health (CA-30969, CA-28476, CA29139, CA-159-89, and CA-33587)  相似文献   
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Introduction: Opioid-induced rigidity often makes bag-mask ventilation difficult or impossible during induction of anesthesia. Difficult ventilation may result from chest wall rigidity, upper airway closure, or both. This study further defines the contribution of vocal cord closure to this phenomenon.

Methods: With institutional review board approval, 30 patients undergoing elective cardiac surgery participated in the study. Morphine (0.1 mg/kg) and scopolamine (6 micro gram/kg) given intramuscularly provided sedation along with intravenous midazolam as needed. Lidocaine 10% spray provided topical anesthesia of the oropharynx. A fiberoptic bronchoscope positioned in the airway photographed the glottis before induction of anesthesia. A second photograph was obtained after induction with 3 micro gram/kg sufentanil administered during a period of 2 min. A mechanical ventilator provided 10 ml/kg breaths at 10/min via mask and oral airway with jaw thrust. A side-stream spirometer captured objective pulmonary compliance data. Subjective airway compliance was scored. Pancuronium (0.1 mg/kg) provided muscle relaxation. One minute after the muscle relaxant was given, a third photograph was taken and compliance measurements and scores were repeated. Photographs were scored in a random, blinded manner by one investigator. Wilcoxon signed rank tests compared groups, with Bonferroni correction. Differences were considered significant at P <0.05.

Results: Twenty-eight of 30 patients exhibited decreased pulmonary compliance and closed vocal cords after opioid induction. Two patients with neither objective nor subjective changes in pulmonary compliance had open vocal cords after opioid administration. Both subjective and objective compliances increased from severely compromised values after narcotic-induced anesthesia to normal values (P = 0.000002) after patients received a relaxant. Photo scores document open cords before induction, progressing to closed cords after the opioid (P = 0.00002), and opening again after a relaxant was administered (P = 0.00005).  相似文献   

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OBJECTIVE: Although VATS lobectomy has been demonstrated to be safe and effective, the technique is not widely practiced. This may, in part, reflect difficulty in acquiring appropriate skills. We have evaluated the effect of experience and training on surgical outcomes during the development and establishment of a VATS lobectomy programme. METHODS: Data were collected prospectively on 276 consecutive VATS lobectomies under the care of a single consultant as either the primary surgeon or supervising four trainees. The series was divided into cohorts of 46 patients. These comprised one trainee cohort and five sequential consultant cohorts. Statistical analysis utilised standard tests of significance. RESULTS: Increasing experience with the VATS lobectomy programme was associated with a significant reduction in operating time but intraoperative blood loss and postoperative stay were not influenced by increasing consultant surgical experience. Training was associated with a mean increase of 22 min operative time (p=0.0005) but no increase in intraoperative blood loss, morbidity, mortality or postoperative stay. The 46 trainee operative times were similar to the first 46 consultant cases. CONCLUSIONS: VATS lobectomy can be safely taught to trainee thoracic surgeons. However, in view of the limited number of centres undertaking VATS lobectomy, training should be coordinated at a national level to concentrate experience and improve uptake of this technique.  相似文献   
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SUMMARY. The relationship between mother and observer in mother-infant observation as described by Esther Bick is examined. Specifically, the question as to whether this relationship influences what is being observed is considered.
The author gives an account of her own relationship as an observer with a mother. The mother was an epileptic and fell with her baby (then six weeks old) causing the baby to suffer a broken skull. Exploration of events during the period of observation leads to the conclusion that the relationship between the mother and the observer was one of transference. Within this transference the observer seemed to be the mother of the one observed. This together with the effects on the observed mother's unconscious conflict with her own mother due to epilepsy is described.
Given transference in the mother-observer relationship doubts are raised as to the tenability of the attitude of distance and non-interference prescribed for the observer. The conclusion is drawn that, in any case, the role of the observer is a participant role, which poses the epistemological problem of the interference of the observer with the observed.  相似文献   
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Background  Research has demonstrated that optimism and “positive illusions” can be used a coping mechanism among those facing adversity. Gamblers are a little studied group who also experience adversity and uncertainty. They often feel considerable levels of frustration, guilt, anger and a sense of feeling cheated after making significant losses. In order to deal with such feelings it is hypothesized that these individuals will search for positive consequences from their behaviour in order to offset this negative affect. Objectives  To (1) determine whether after gambling, gamblers compensate and reduce negative affect by identifying positive consequences from experiencing a loss, and (2) identify types of strategies which gamblers employ and consider how these should be classified. Materials and Methods  Eighty-seven regular slot machine gamblers were interviewed in a variety of environments housing slot machines. Each participant was asked a series of questions in a semi-structured format, to explore possible styles of positive thinking. Results  Nine types of ‘positive thinking’ experienced by gamblers were identified. These included Comparative thinking, Prophylactic thinking, Biased frequency thinking, Responsibility avoidance, Chasing Validation, Prioritization, Resourcefulness, Thoughtfulness, and Fear Reduction. Gamblers who were positive thinkers experienced significantly less guilt than non-positive thinkers. Conclusions  While reduction of negative affect may be perceived as positive in many other contexts, it is argued that it may counteract efforts to promote responsible gambling. Clinical implications and directions for future research are discussed.  相似文献   
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Mercury sphygmomanometers have been commonly used in primary care to measure blood pressure but are associated with bias. Electronic blood pressure machines are being introduced in many practices and have anecdotally been associated with higher recorded blood pressure. This study examined recorded blood pressure in four practices before and after electronic blood pressure machine introduction. No consistent change in mean blood pressure was apparent following their introduction, but there was a large and significant fall in terminal digit preference suggesting improved precision of recording.  相似文献   
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