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991.
992.
A 3-year retrospective study of 173 neonates treated with extracorporeal membrane oxygenation in the United Kingdom identified 9 cases of irreversible lung dysplasia, including alveolar capillary dysplasia (n = 5), surfactant protein B deficiency (n = 1), pulmonary hypoplasia (n = 1), pulmonary lymphangiectasis (n = 1), and combined lymphangiectasis and hypoplasia (n = 1).  相似文献   
993.
OBJECTIVE: To assess the effect of head position and football equipment (ie, helmet and shoulder pads) on cervical spinal cord space in individuals lying supine on a spine board. DESIGN AND SETTING: The independent variables were head position (0-cm, 2-cm, and 4-cm occiput elevation with no helmet and shoulder pads and with helmet and shoulder pads) and cervical spine level (C3, C4, C5, C6, and C7). The 3 dependent variables were sagittal space available for the cord (SAC) (mm), sagittal spinal-cord diameter (mm), and cervical-thoracic angle ( degrees ), determined via magnetic resonance imaging. SUBJECTS: Twelve men (age = 24.3 +/- 2.1 years; height = 181.1 +/- 5.7 cm; weight = 93.9 +/- 3.6 kg). MEASUREMENTS: Sagittal space available for the cord was determined by subtracting the sagittal spinal-cord diameter from the corresponding sagittal spinal-canal diameter. The spinal-canal diameter was measured as the shortest distance from the vertebral body to the spinolaminar line at each of the spinal levels. Each measurement was taken 3 times, and the 3 measurements were averaged. RESULTS: Sagittal space available for the cord was significantly greater (P <.01) for 0-cm (mean = 5.50 mm) than for 2-cm (mean = 4.86 mm) and 4-cm (mean = 5.07 mm) occiput elevation. SAC was also significantly greater (P <.01) for the equipment condition (mean = 5.34 mm) than for the 2-cm and 4-cm elevation levels. No significant difference (P =.093) in SAC existed between 0-cm elevation and the equipment condition. CONCLUSIONS: The helmet and shoulder pads should be left on during spine-board immobilization of the injured football player. Similarly, during spine-board immobilization of an individual without football helmet and shoulder pads, the head should be maintained at 0 cm of occiput elevation. Sagittal spinal-cord space is optimized in both of these conditions.  相似文献   
994.
Here we investigated the impact of visual discrimination training on neuronal responses to parts of images and to whole images in inferotemporal (IT) cortex. Monkeys were trained to discriminate among 'baton' stimuli consisting of discrete top and bottom parts joined by a vertical stem. With separate features at each end, we were able to manipulate the two parts of each baton independently. After training the monkeys, we used single-cell recording to compare neuronal responses to learned and unlearned batons. Responses to learned batons, though not enhanced in strength, were enhanced in selectivity for both individual parts and for whole batons. Whole-baton selectivity arose from a form of conjunctive encoding whereby two parts together exerted a greater influence on neuronal activity than predicted by the additive influence of each part considered individually. These results indicate a possible neural mechanism for holistic or configural effects in expert versus novice observers.  相似文献   
995.
The question, 'Does religion (or spirituality) cause physical health benefits?' may be given at least four diverging interpretations in terms of causal path diagrams. In common usage, the question may be interpreted to indicate that religion causally influences health by: (1) any mechanism, including well-established factors such as social support and improved health behaviors; (2) additional mechanisms, such as enhanced positive psychological states (e.g. faith, hope, inner peace) acting through psychoneuroimmunologic or psychoneuroendocrinologic pathways; (3) offering psychological strength for acquiring or maintaining positive health behaviors; or (4) causally influencing health by distant healing or intercessory prayer. We review historical confusion between these interpretations, arguing that disentangling them is important for collaborative health care, promotion and research.  相似文献   
996.
The successful management of multi-space orofacial odontogenic infections involves identification of the source of the infection, the anatomical spaces encountered, the predominant microorganisms that are found during the various stages of odontogenic fascial space infection, the impact of the infectious process on defense systems, the ability to use and interpret laboratory data and imaging studies, and a thorough understanding of contemporary antibiotic and supportive care. The therapeutic goals, when managing multi-space odontogenic infections, are to restore form and/or function while limiting patient disability and preventing recurrence. Odontogenic infections are commonly the result of pericoronitis, carious teeth with pulpal exposure, periodontitis, or complications of dental procedures. The second and third molars are frequently the etiology of these multi-space odontogenic infections. Of the two teeth, the third molar is the more frequent source of infection. Diagnostic imaging modalities are selected based on the patient's history, clinical presentation, physical findings and laboratory results. Periapical and panoramic x-rays are reliable initial screening instruments used in determining etiology. Magnetic resonance imaging and computed tomography are ideal imaging studies that permit assessment of the soft tissue involvement to include determining fluid collections, distinguishing abscess from cellulitis, and offering insight as to airway patency. Antibiotics are administered to assist the host immune system's effort to control and eliminate invading microorganisms. Early infections, first three (3) days of symptoms, are primarily caused by aerobic streptococci which are sensitive to penicillin. Amoxicillin is classified as an extended spectrum penicillin. The addition of clavulanic acid to amoxicillin (Augmentin) increases the spectrum to staphylococcus and other anaerobes by conferring beta-lactamase resistance. In late infections, more than three (3) days of symptoms, the predominant microorganisms are anaerobes, predominantly Peptostreptococcus, Fusobacterium, or Bacteroides, that are resistant to penicillin. Clindamycin is an attractive alternative drug for first line therapy in the treatment of these infections. The addition of metronidazole to penicillin is also an excellent treatment choice. Alternatively, Unasyn (Ampicillin/Sublactam), should be considered. The mainstay of management of these infections remains appropriate culture for bacterial identification, timely and aggressive incision and drainage, and removal of the etiology. It is usually preferable to drain multi-space infections involving the submandibular, submental, masseteric, pterygomandibular, temporal, and/or lateral pharyngeal masticator spaces, as early as possible from an extraoral approach. Trismus and airway management are important considerations and may preclude the selection of other surgical approaches. The patients with multi-space infections should be hospitalized and patient care provided by experienced clinicians capable of management of airway problems, in administration of parenteral antibiotics and fluids, utilization of interpretation of laboratory and diagnostic imaging studies, and control of possible surgical complications.  相似文献   
997.
998.
OBJECTIVES: To develop a formula to predict mortality for intensive care unit patients between day 5 in an intensive care unit and 100 days after hospital discharge from a community hospital. DESIGN: Retrospective 1-yr derivation study with validation on a subsequent year's intensive care unit population. SETTING: An 850-bed, not-for-profit community hospital with three adult intensive care units, including medical-surgical, cardiac-medical, and cardiac-surgical units. PATIENTS: The development patient set included 4045 consecutive adult admissions to the intensive care unit between July 1995 and June 1996. The validation sample consisted of 4084 admissions between July 1996 and June 1997. RESULTS: During the first year, 100-day posthospital discharge mortality was predicted by the combination Acute Physiology and Chronic Health Evaluation (APACHE) III predicted mortality on day 5 of >0.92 or the product of day 1 and day 5 APACHE predicted mortality of >0.40, with an increase in the APACHE predicted mortality from day 1 to day 5 of >0.10. Specificity in the development cohort was 0.99, sensitivity was 0.30, and positive predictive value was 0.95. The second-year validation study demonstrated a specificity, sensitivity, and positive predictive value of 0.98, 0.29, and 0.91, respectively, when applying the model to the validation sample. CONCLUSIONS: By using readily available APACHE III data, we were able to identify patients at high risk of dying between intensive care unit day 5 and 100 days after discharge. Although the low sensitivity limits the number of patients for whom death at 100 days is predicted, the high specificity and positive predictive value suggests this information may provide useful information for families and physicians. If these formulas can be validated in diverse institutional settings, decisions regarding short- and long-term outcomes may be improved by using objective survival predictions from two time points.  相似文献   
999.
1000.
Patients in atrialfibrillation (AF) who fail external cardioversion are usually regarded as in permanent AF. Internal cardioversion may revert many such patients into sinus rhythm (SR) but the majority relapse rapidly into AF. We investigated whether internal cardioversion followed by biatrial pacing is an effective to restore and subsequently maintain SR in patients with permanent AF. Patients in permanent AF underwent internal cardioversion that was followed by biatrial temporary pacing for 48 hours. Those who remained in SR received a permanent biatrial pacemaker programmed to a rate responsive mode with a lower rate 90 beats/min. Primary end point of the study included maintenance in SR 3 months after internal cardioversion. Sixteen patients (14 men, 57 +/- 11 years) were cardioverted. The median duration of AF was 24 months (quartiles, Q1 = 8.5 and Q3 = 102) and mean left atrium diameter was 48 +/- 04 mm. A permanent biatrial pacemaker was implanted in 11 patients. At a mean fallow-up of 15 months (range 4 to 24), 8 patients remained in SR for more than 3 months. AF was eliminated in 5 patients, while in two a second internal cardioversion on amiodarone was required. Antiarrhythmic therapy was used in half of our population and did not predict the long-term maintenance of SR. Following internal cardioversion with continuous biatrial pacing, 50% of patients with permanent AF were maintained for prolonged periods in SR. This is a new modality of treatment of permanent AF directed to the maintenance of SR that provides a further therapeutic option in end-stage AF.  相似文献   
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