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991.
This methodological study examined the impact of antisocial personality disorder (APD) and other psychiatric comorbidity on drug use and treatment retention in 513 new admissions to methadone maintenance treatment. Patients were classified into one of four groups: APD ONLY, APD plus other psychiatric disorder (APD MIXED), other psychiatric disorder, and no psychiatric disorder. Patients completed research assessments and were then followed for 1 year of treatment. Patients with APD had longer histories of heroin and cocaine use than non-APD patients and were more likely to meet criteria for cocaine dependence. Distinct clinical profiles emerged that differentiated APD ONLY from APD MIXED. APD ONLY patients exhibited higher rates of cocaine and heroin use, whereas those with APD MIXED exhibited higher rates of benzodiazepine use. Self-report measures supported urinalysis results, but group differences did not affect treatment retention. These differences in clinical profiles should be considered when evaluating treatment performance in substance abusers with APD.  相似文献   
992.
There is still no consensus as to which physiologic marker should be used as a trigger for the initiation of non-invasive positive pressure ventilation (NPPV) in patients with amyotrophic lateral sclerosis (ALS). Current practice parameters recommend that the decision to begin treatment be based upon forced vital capacity (FVC) measurements. A prospective, randomized study was performed in 20 ALS patients who had an FVC of 70-100%. Patients received baseline assessments including: ALS functional rating scale-respiratory version (ALSFRS-R), pulmonary symptom scale, Short form 36 (SF-36), FVC%, maximal inspiratory pressure (MIP), maximal expiratory pressure (MEP), and nocturnal oximetry. Patients were randomized to receive NPPV based upon nocturnal oximetry studies suggesting oxygen desaturation <90% for one cumulative minute ("early intervention") or a FVC <50% ("standard of care"). At enrollment, there was no significant correlation between FVC% and the ALSFRS-R, symptom score, MEP, MIP, or duration of nocturnal desaturation <90%. An increase in the vitality subscale of the SF-36 was demonstrated in 5/6 patients randomized to "early intervention" with NPPV. Our data indicate that FVC% correlates poorly with respiratory symptoms and suggests that MIP and nocturnal oximetry may be more sensitive measures of early respiratory insufficiency. In addition, intervention with NPPV earlier than our current standard of care may result in improved quality of life.  相似文献   
993.
The authors report the case of a young man who suffered multiple injuries in a motor vehicle accident, the most significant of which arose in the brain, creating an unusual clinical syndrome. After experiencing an initial coma for several days, the patient was found to have a right-sided homonymous hemianopsia and a right hemiparesis, which was more marked at the shoulder and was accompanied by preservation of finger movement. Dystonic movements appeared 2 months later and progressed, along with increased spasticity on volition, to severe uncontrolled arm movements at 2 years postinjury. This motor disorder continued to worsen during the following 6 years prior to the patient's death. At autopsy, the left side of the brain was observed to have marked atrophy of the optic tract, a partial lesion of the posterior portion of the medial segment of the globus pallidus (GP), and a reduction in the size of the internal capsule at the level of the GP, suggesting impaired circulation to these areas at the time of injury. The isolated lesion of the internal segment of the GP was the presumed cause of the dystonia, acting through an alteration in thalamic inhibition. The atrophic subthalamic nucleus was the probable cause of the hemiballismus. The authors speculate that this and other delayed and progressive features of this case were the result of an active, but disordered, adaptive process that failed to compensate and, instead, caused even greater problems than the original injury.  相似文献   
994.
Xenon anaesthesia is thought to have minimal haemodynamic side-effects. It is, however, expensive and requires special delivery systems for economic use. In this randomised cross-over study, we: (i) investigated the haemodynamic profile and recovery characteristics of xenon compared with propofol sedation in postoperative cardiac surgery patients, and (ii) evaluated a fully closed breathing system to minimise xenon consumption. We demonstrated a significantly faster recovery from xenon (3 min 11 s) than propofol sedation (25 min 23 s). Relative to propofol, xenon sedation produced no change in heart rate or mean arterial pressure and there were significantly higher mean values for central venous pressure (10.6 vs. 8.9 mmHg), pulmonary artery occlusion pressure (11.2 vs. 9.5 mmHg), mean pulmonary artery pressure (20.1 vs. 18.3 mmHg) and systemic vascular resistance index (2170 vs. 1896 dyn.s.cm-5.m-2). The haemodynamic profile seen with propofol reflected its known vasodilator effects. This was supported by the almost identical left ventricular stroke work indexes seen with both methods of sedation.  相似文献   
995.
996.
BACKGROUND: Although full-thickness burns present no difficulty to clinical judgment, accurate assessment of burn depth immediately after injury in partial thickness burns has always been difficult. METHODS: Thermal burns (applied by a 3-mm-diameter brass rod heated to 50 degrees--80 degrees C for 20 seconds) were induced on the skin of anesthetized hairless mice. Anesthesia was maintained throughout all experiments. Both burns and normal skin were investigated noninvasively in vivo using fiber-optic confocal imaging (FOCI) microscopy (excitation, 488 nm; detection, 505 nm). RESULTS: Autofluorescence was detected in burned skin, and the depth of the autofluorescent region was found to correlate with the intensity of heat applied. Cool water treatment (for 20 minutes immediately after burn induction) significantly reduced the progressive increase in autofluorescence in deeper layers of the skin over the 4-hour postburn observation period. Histology showed burn-associated changes at a lower temperature than that at which autofluorescence was first detected in vivo by FOCI. However, there was a good correlation (r = 0.78) between depth of damage revealed by FOCI compared with that by histology. CONCLUSION: These results suggest that FOCI may be used to provide an index of burn depth.  相似文献   
997.
998.
999.
A history and physical examination, focusing on risk factors for cardiac, pulmonary and infectious complications, and a determination of a patient's functional capacity, are essential to any preoperative evaluation. In addition, the type of surgery influences the overall perioperative risk and the need for further cardiac evaluation. Routine laboratory studies are rarely helpful except to monitor known disease states. Patients with good functional capacity do not require preoperative cardiac stress testing in most surgical cases. Unstable angina, myocardial infarction within six weeks and aortic or peripheral vascular surgery place a patient into a high-risk category for perioperative cardiac complications. Patients with respiratory disease may benefit from perioperative use of bronchodilators or steroids. Patients at increased risk of pulmonary complications should receive instruction in deep-breathing exercises or incentive spirometry. Assessment of nutritional status should be performed. An albumin level of less than 3.2 mg per dL (32 g per L) suggests an increased risk of complications. Patients deemed at risk because of compromised nutritional status may benefit from pre- and postoperative nutritional supplementation.  相似文献   
1000.
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