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991.
Localized bone marrow relapse is rare in acute lymphoblastic leukemia. Discordant bone marrow specimens were found in an 11-year-old asymptomatic girl who had been in remission for six years and off chemotherapy for 2 1/2 years. One bone marrow sample showed marked leukemic infiltration, whereas marrow from another site was normal. Three months later, with normal peripheral blood counts, she developed severe back pain and x-ray evidence of vertebral collapse and periosteal changes in the pubic bone. At that time three of the four areas of bone marrow sampled showed leukemic involvement. Reinduction therapy was begun, and she is now in remission on maintenance chemotherapy. At this time, it is unclear whether routine performance of marrow aspirations and biopsies from multiple sites, in periodic follow-up examinations of patients with acute leukemia would allow earlier detection of relapse frequently enough to justify the procedure. The issue of localized bone marrow involvement, if more common than previously reported, should be addressed at the time a decision is being made to discontinue therapy.  相似文献   
992.
One percent of all pregnancies are found to have an antenatal abnormality; of these, 20% involve the genitourinary system. Today, controversy still exists regarding the postnatal management of some antenatal abnormalities detected by ultrasound. We present a case in which antenatal hydronephrosis initially detected by ultrasound appeared to resolve in utero. Postnatally, the child developed Citrobacter diversus urosepsis, meningitis, and cerebral abscess. Voiding cystourethrogram obtained after resolution of sepsis revealed grade IV reflux. This case underscores the importance of a full postnatal evaluation for all children with antenatal hydronephrosis and alerts clinicians to a virulent pathogen not commonly associated with urinary tract infection.  相似文献   
993.
BACKGROUND: It is well accepted that heavy physical exertion can trigger the onset of myocardial infarction, but the mechanism is uncertain. As platelet and endothelial function play an important role in thrombotic events, platelet and prostacyclin responses to maximal treadmill exercise were studied. METHODS/RESULTS: The study subjects were 40 healthy men, mean (SEM) age 29 (5) years. Platelet aggregation was measured on a four channel aggregometer. Plasma 6-keto-prostaglandin F1alpha was analysed using an enzyme immunoassay technique. Upright posture and exercise produced an increase in platelet aggregability, as indicated by a fall in the threshold concentration of adrenaline (epinephrine) from 7.6 (1.5) microM at rest to 4.3 (1.0) microM after exercise (p = 0.002). The collagen lag time became significantly shorter with exercise (from 79.1 (3.1) seconds at rest to 71.9 (2.6) seconds after exercise, p = 0.003). Exercise was also associated with a 55% increase in plasma 6-keto-prostaglandin F1alpha (from 38.1 (75%CI 29.0 to 46.5) pg/ml at rest to 59.2 (47.3 to 66.8) pg/ml after exercise, p<0.001). CONCLUSIONS: In healthy male subjects, upright posture and maximal exercise increased platelet aggregability but this increase was counteracted by an increase in prostacyclin production. In patients with endothelial dysfunction, a reduced prostacyclin response to exercise may promote a transient prothrombotic imbalance that may trigger cardiovascular disease onset.  相似文献   
994.
OBJECTIVE: Bilateral staple lung volume reduction surgery (LVRS) immediately improves pulmonary function and dyspnea symptoms in patients with advanced heterogeneous emphysema to a greater degree than do unilateral procedures. However, the long-term outcome after these surgical procedures needs to be critically evaluated. We compare 2-year survival of patients who underwent unilateral versus bilateral video-assisted LVRS in a large cohort treated by a single surgical group. METHODS: The cases of all 260 patients who underwent video-assisted thoracoscopic stapled LVRS from April 1994 to March 1996 were analyzed to compare results after unilateral versus bilateral procedures. Overall survival was calculated by Kaplan-Meier methods; Cox proportional hazard methods were used to adjust for patient heterogeneity and baseline differences between groups. RESULTS: Overall survival at 2 years was 86.4% (95% CI 80. 9%-91.8%) after bilateral LVRS versus 72.6% (95% CI 64.2%-81.2%) after unilateral LVRS (P =.001 for overall survival comparison). Improved survival after bilateral LVRS was seen among high- and low-risk subgroups as well. Average follow-up time was 28.5 months (range, 6 days to 46.6 months) for the bilateral LVRS group and 29.3 months (range, 6 days to 45.0 months) for the unilateral LVRS patients. CONCLUSIONS: Comparison of unilateral versus bilateral thoracoscopic LVRS procedures for the treatment of emphysema reveals that bilateral LVRS by video-assisted thoracoscopy resulted in better overall survival at 2-year follow-up than did unilateral LVRS. This survival study, together with other studies demonstrating improved lung function after bilateral LVRS, suggests that bilateral surgery appears to be the procedure of choice for patients undergoing LVRS for most eligible patients with severe heterogeneous emphysema.  相似文献   
995.
PURPOSE: To identify factors that may predict for severe radiation pneumonitis or pneumonopathy (RP), we reviewed a set of simple, commonly available characteristics. METHODS AND MATERIALS: Medical records of 148 lung cancer patients with good performance status (ECOG 0-1) treated definitively with chemoradiation from 6/92-6/98 at the University of Pennsylvania were reviewed. Actuarial survival and the crude rate of severe radiation pneumonitis were determined as a function of several variables. Potential predictive factors examined included age, gender, histology, stage, pulmonary function, performance status (0 vs. 1), weight loss, tumor location, radiation dose, initial radiation field size, chemotherapy regimen, and timing of chemotherapy. Univariate analysis (log-rank test) was performed for each variable. Multivariate analysis was performed using linear regression. RESULTS: Median survival for the entire cohort was 14.7 months. Four patients were inevaluable for pneumonitis due to early death from progressive disease. Of the remaining 144 evaluable patients, 12 (8.3%) experienced severe RP. The most significant factor predicting for severe RP was performance status (p < 0.003). The risk of severe RP was 16% for PS-1 patients vs. 2% for PS-0 patients. Women were significantly more likely to develop severe RP than men (p = 0.01). Among 67 patients for whom pre-radiation therapy pulmonary function data were available, forced expiratory volume of the lung in 1 second (FEV(1)) was also significant (p = 0. 03). No patient suffering severe RP had a pretreatment FEV(1) > 2.0 liters. The median radiation dose was 59.2 Gy and median initial radiation field size was 228 cm(2). Neither radiotherapy factor predicted for RP. Other factors studied, including chemotherapy drugs, and schedule, also were not significant predictors of severe RP. CONCLUSIONS: Pretreatment performance status, gender, and FEV(1) are significant predictors of severe radiation pneumonopathy, at least when using conventional radiation fields and doses. Complex radiation dose-volume algorithms that attempt to predict lung complication probabilities should probably incorporate these simply obtained clinical parameters.  相似文献   
996.

Introduction

We describe a novel physiologic penile prosthesis that uses shape memory alloy properties to mimic the transition between a flaccid and erect penis using magnetic induction instead of hydraulic pressure.

Aim

To evaluate the parameters of magnetic induction to activate a shape memory alloy implantable penile prosthesis.

Methods

We prototyped an implantable penile prosthesis cylinder using temperature-tuned nickel titanium alloy tubes laser cut to specifications.The device was then tested implanted in an animal tissue model and in cadaveric tissue. Testing consisted of placing the device deactivated in its more malleable and compressed state, then activating it using an external inducer wand while measuring temperature changes that occur on the surface of the device, within the tissue, and at the skin surface.

Main Outcome Measures

Our main outcome measures were the efficiency of activation and thermal safety of this approach.

Results

Using a handheld magnetic inductor, we were able to successfully activate the SMA penile prosthesis with no direct contact under 45 seconds. This handheld wand produced a magnetic field that penetrated tissue and caused the appropriate phase change within the prosthesis. Tissue temperature (middle and surface probes) in the animal tissue model increased only a few degrees Celsius during the activation process, and never exceeded 28 degrees Celsius from a baseline at room temperature ~ 25 degrees Celsius. We encountered similar results without a notable change in tissue temperature in the cadaveric tests. The fully activated device resisted buckling forces of 2.66 kgf ± 0.045.

Clinical Implications

This non-hydraulic shape memory prosthesis obviates the needs for reservoirs and pumps, and the wand-based interaction with the device may be easier to use.

Strength & Limitations

This technology represents a fundamental departure from the hydraulic-based penile prosthesis and has comparable mechanical properties as current-marked devices. It appears to show thermal safety in controlled environments, however real-world use would need further studies. Further optimization of prototypes needs to be done prior to human clinical trials.

Conclusion

A shape memory penile prosthesis is a promising alternative to hydraulic-based penile prostheses and can be activated safely and efficiently using magnetic induction in our models of the human penis.Le BV, McVary KT, McKenna K, et al. Use of Magnetic Induction to Activate a “Touchless” Shape Memory Alloy Implantable Penile Prosthesis. J Sex Med 2019;16:596–601.  相似文献   
997.
Objective: Insomnia frequently occurs alongside distressing tinnitus, and greater tinnitus severity is associated with more sleep disturbance. Insomnia and tinnitus probably share common underlying processes and sleep studies show striking similarities between primary and tinnitus-related insomnia. This is the first study to evaluate outcomes following insomnia-specific Cognitive Behavioural Therapy (CBTi) for tinnitus-related insomnia in a “real world” clinic.

Design: Treatment was six-sessions of group-based CBTi. Measures of insomnia, sleep diaries, tinnitus distress, psychological distress, anxiety and depression were completed pre-intervention, post-intervention and at six-weeks follow up.

Study Sample: Participants were 24 adults with chronic, distressing tinnitus and associated sleep disturbance. Twenty-two completed treatment.

Results: CBTi was associated with significant improvements from pre-intervention to post-intervention maintained at follow up in insomnia, sleep-diary measures, tinnitus distress, psychological distress, anxiety and depression, largely maintained at follow-up. Reliable improvements were reported in insomnia (by 67% of patients), tinnitus distress (by 50% of patients) and psychological distress (by 38% of patients) post-intervention.

Conclusions: The results suggest that CBTi is associated with reduced insomnia and distress for patients reporting chronic and distressing tinnitus with related insomnia. Further research into CBTi for this population, using utilising robust, randomised controlled designs, is warranted.  相似文献   

998.
Disproportionate exercise limitation in patients with cardiovascular disease is a common problem faced by clinical cardiologists and other physicians. Symptoms may be attributed to psychological factors or hypothetical pathophysiological mechanisms that are difficult to confirm clinically. This case report describes how the use of metabolic exercise testing in a 28 year old woman with morphologically and haemodynamically mild hypertrophic cardiomyopathy and severe exercise limitation led to the diagnosis of an alternative cause for the patient's symptoms, namely a primary disturbance of the mitochondrial respiratory chain probably caused by a nuclear encoded gene defect.  相似文献   
999.
1000.
Several post-mortem studies have identified increases of 5-HT1A receptor density in frontal cortical areas in schizophrenic patients, and one has found increases in the cerebellar vermis. Clozapine has moderate affinity at the 5-HT1A receptor, and this may be of therapeutic importance. This positron emission tomography (PET) study attempted to replicate the post-mortem findings in vivo and sought an occupancy effect of clozapine at the 5-HT1A receptor. We recruited healthy controls, and patients with schizophrenia who were divided into those receiving clozapine and those receiving neuroleptics lacking 5-HT1A receptor affinity. Each volunteer received a PET scan, using the 5-HT1A receptor radioligand [carbonyl-11C]WAY-100635, and a magnetic resonance imaging scan. The cerebellar vermis was examined by comparing time-activity data between groups. For other brain regions (the raphe and subdivisions of the cerebral cortex), binding potential images were generated to reflect receptor density, then analysed using 'region of interest' and voxel-by-voxel methods. No significant changes of 5-HT1A receptor density were found in schizophrenic patients compared to controls. Two other PET studies, containing drug na?ve rather than medicated schizophrenic patients, have also reported no increase in 5-HT1A receptor density in the frontal cortex. The results obtained in vivo bring into question the importance of the receptor in the pathophysiology of the illness. Clozapine did not occupy the 5-HT1A receptor at clinical doses. This is consistent with recent related PET results: 5-HT1A agonists do not appear to measurably block the binding of antagonist radiotracers in man at doses that are pharmacologically active but which are limited by tolerability.  相似文献   
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