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1.
OBJECTIVES: To compare gastric tonometry (pHi) with estimates of pHi in ill injured patients, and to correlate pHi with haemodynamic variables. DESIGN: Prospective, non-interventional study. SETTING: ICU of Level I trauma centre, USA. MAIN OUTCOME MEASURES: 154 gastric tonometry measurements were compared with physicians' estimates of adequacy of resuscitation. Resuscitation was categorised as inadequate (pHi < 7.35) or adequate (pHi> or = 7.35). Measured and estimated pHi were also compared with oxygen delivery, oxygen consumption, cardiac index, mixed venous O2 saturation, and critical illness scores. RESULTS: Estimated pHi was often higher than measured pHi in the judgement of all four surgical intensive care physicians. Measured pHi correlated positively with mixed venous O2 tension (r = 0.21). There were significant negative correlations between measured pHi and both oxygen delivery (r = -0.25) and oxygen consumption (r = 0.28). Estimated pHi correlated positively with mean arterial pressure (r = 0.21) and hospital day (r = 0.26); it correlated negatively with pulmonary arterial elastance (r = -0.35). CONCLUSION: Experienced intensive care physicians tended to overestimate visceral perfusion, which suggests that gastric tonometry adds useful information over and above routine haemodynamic indices. Arterial blood pressure and mixed venous oxygen saturation correlated better with measured pHi than with other indices of perfusion.  相似文献   
2.
PURPOSE: To evaluate the incidence and specificity of fracture of the first rib as an indicator of child abuse and to determine a mechanism of fracture. MATERIALS AND METHODS: All infants and young children with rib fractures who were seen at the radiology department of an academic medical center over a 2-year period were identified from the radiology data base. RESULTS: Rib fractures were attributed to child abuse in 12 of 35 children identified. Apart from a neonate with congenital osteogenesis imperfecta, only three children, all abused, had first-rib fracture, one bilaterally. Two additional children with first-rib fracture were identified from years prior to the study period. In four children, first-rib fractures were "isolated," without fractures of adjacent bones. CONCLUSION: Child abuse should be considered in cases of pediatric rib fracture, particularly fracture of the first rib. Possible mechanisms for first-rib fracture include impact force, compressive force, and shaking or acute axial load (slamming), which cause an indirect fracture.  相似文献   
3.
BACKGROUND: The need for cardiopulmonary bypass in the treatment of penetrating heart injuries is debated. OBJECTIVES: To review our experience with penetrating heart injuries and determine the indications and outcome for cardiopulmonary bypass. DESIGN: Retrospective review. SETTING: A university-based, level I trauma center. PATIENTS: All victims of penetrating heart injury presenting between July 1, 1989, and December 31, 1995. METHODS: Medical records were reviewed for demographic and physiological data, operative findings, and outcome. RESULTS: Overall survival for 106 patients with penetrating heart injury was 55%. In an effort to resuscitate the heart, 4 patients with unresponsive cardiogenic shock were placed on cardiopulmonary bypass; none survived. Of 30 patients with multiple-chamber injuries, 11 presented with signs of life and 7 survived. Cardiopulmonary bypass was essential to repair complex injuries in 2 of the 7 survivors. CONCLUSION: Cardiopulmonary bypass was ineffective in salvaging patients with cardiogenic shock but was essential in some patients with complex multiple-chamber cardiac injuries that could not be exposed and repaired by other means.  相似文献   
4.
The behavior of 34 California ground squirrels was measured in the field, and all behavioral samples occurring within the same 5?×?5 m quadrat of the 100?×?100 m study area were pooled. The number and proximity of burrows, rocks, and trees around the center of each quadrat were measured, and these microhabitat attributes were used as predictor variables in multiple regression analyses in an attempt to account for interquadrat variance in time allocated to common behaviors. For the 3 most common behaviors (forage, vigilance, and locomotion), 56–75% of the variance among quadrats was accounted for by the microhabitat variables. Each behavior was accounted for by a unique combination or ordering of the predictor variables. Testable hypotheses are offered as to the adaptive significance of the observed behavior–habitat correlations. Results support the contention that the utility of a behavior varies spatially according to the probability of encountering biologically important factors and that these probabilities are partly predictable by small-scale characteristics of the habitat. (68 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
5.
Animal communication theory holds that many signals have evolved from nonsignal precursors. This field and laboratory study of California ground squirrels (Spermophilus beecheyi) provides evidence for the coexistence of such a precursor with its derived display. The precursor is an ancient, endogenously sequenced (syntactic) pattern of cephalocaudal grooming movements (CCGs) shared by all rodent suborders. The following evidence supports the hypothesis that a supernormal version of this pattern has been selected for signal function. Syntactic CCGs in the field (a) were more rigidly stereotyped than ordinary syntactic CCGs in the laboratory; (b) differed from laboratory syntactic CCGs in other ways that enhanced their conspicuousness, in part through exaggeration of the syntactic cephalocaudal pattern; (c) were associated with scent marking and social staring; and (d) were associated with intrasexual agonistic encounters that did not escalate to fighting. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
6.
In this paper we present the development of a magnetic moment reference material for low moment magnetic samples. We first conducted an inter-laboratory comparison to determine the most useful sample dimensions and magnetic properties for common instruments such as vibrating sample magnetometers (VSM), SQUIDs, and alternating gradient field magnetometers. The samples were fabricated and then measured using a vibrating sample magnetometer. Their magnetic moments were calibrated by tracing back to the NIST YIG sphere, SRM 2853.  相似文献   
7.
This study examined the relationships between state-level fiscal and demographic variables and identification rates and cumulative placement rates for certain categories of special education students in 1976, 1980, and 1983. The study explored the feasibility of using extant national data to study implementation of special education programs. Identification rates for students with learning disabilities and emotional disturbance were associated with level of state per-capita income and proportion of rural school-age population. States with higher per-capita income tended to have higher cumulative placement rates in special classes and all more restrictive settings.  相似文献   
8.
PURPOSE: The bilateral deficit is characterized by a decrease in maximum voluntary contraction (MVC) force during bilateral activation of homologous muscles compared with sum of the forces produced during unilateral MVC of the muscles. A proposed relationship between the bilateral deficit and the ability to activate high threshold motor units was investigated. The effects of muscle fatigue, induced using two contraction speeds, on the size of the bilateral deficit were measured. Based on previously published findings, it was expected that fast velocity isokinetic contractions compared with slow velocity isokinetic contractions would produce a larger bilateral deficit. It was hypothesized that following a unilateral fatigue protocol, the size of the bilateral deficit at the fast and slow velocities would be comparable. METHODS: The bilateral deficit was measured for isokinetic knee extension in 20 men (age:25 +/- 3 yr) before and after a fatigue protocol performed at 30 and 150 degreesxs(-1). RESULTS: The size of the bilateral deficit was initially the same at both velocities. The fatigue protocol at each contraction speed significantly decreased the maximum voluntary knee extension moment. The size of the bilateral deficit was not influenced by the 150 degrees fatigue protocol (pretest: -14.0% post-test: -12.5%; P > 0.05). However, the size of the bilateral deficit increased following the 30 degreesxs(-1) fatigue protocol (pretest: -13.7%; post-test: -21.9%; P < 0.05). CONCLUSIONS: The failure of the size of the bilateral deficit to be comparable at 30 and 150 degreesxs(-1) following fatigue is contrary to previous published reports that suggested reduced activation of high threshold motor unit is the primary mechanism underlying the bilateral deficit.  相似文献   
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10.
OBJECTIVES: This report presents estimates of surgical and nonsurgical procedures performed in the United States during 1996. Data are presented by characteristics of patients, region of the country, and procedure categories for ambulatory and inpatient procedures separately and combined. METHODS: Estimates in this report are based on data collected from the National Hospital Discharge Survey (NHDS) and the National Survey of Ambulatory Surgery-(NSAS). NHDS provides data on hospital inpatient care, and NSAS provides data on ambulatory surgery in hospitals and in freestanding ambulatory surgery centers. For NHDS, data were collected for approximately 282,000 discharges from 480 non-Federal short-stay hospitals (95 percent response rate). For NSAS, data were collected for approximately 125,000 ambulatory surgery discharges from 488 hospitals and freestanding ambulatory surgery centers (81 percent response rate). RESULTS: An estimated 71.9 million procedures were performed on 39.9 million discharges from hospitals and freestanding ambulatory surgery centers during 1996: 40.4 million procedures were for inpatients, and 31.5 million were for ambulatory patients. Females had more procedures than males, and the rate of procedures increased with age in ambulatory and inpatient settings. The leading procedures for ambulatory surgery patients and inpatients combined were arteriography and angiocardiography, endoscopy of small intestine, endoscopy of large intestine, and extraction of lens.  相似文献   
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