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41.
IntroductionPatients with traumatic brain injury are referred to the neurosurgical unit at James Cook University Hospital, Middlesbrough, either from local accident and emergency departments (direct transfer from the scene) or from other hospitals (indirect transfer). This study looked at the outcome in both groups.Material and methodsThis was a retrospective observational study using trauma audit research network data for patients treated for traumatic brain injury at the neurosurgery department at the neurosurgical unit at James Cook University Hospital.ResultsA total of 356 patients with traumatic brain injury were admitted under the care of neurosurgeons; 143 (40%) of these patients had a neurosurgical procedure. Of the patients undergoing a neurological procedure, 111 patients were transferred directly while 32 were indirect transfers; 213 patients were managed conservatively. Of those managed conservatively, 165 were transferred directly while 48 were indirect transfers.We compared the length of hospital stay and Glasgow Outcome Scale score for the patients based on whether they were conservatively managed or required surgery in the direct and indirect transfer groups. The difference in the length of stay in the surgical and conservative groups following direct and indirect transfer was insignificant (p = 0.07). The time to the operation in direct and indirect transfer was also not statistically significant (p = 0.06).ConclusionPatients are as safe, if not safer, by reaching the nearest trauma unit with facilities for resuscitation and imaging. 相似文献
42.
Enhanced neurogenesis after transient global ischemia in the dentate gyrus of the rat 总被引:53,自引:0,他引:53
Kee NJ Preston E Wojtowicz JM 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2001,136(3):313-320
The dentate gyrus is one of the few areas of the mammalian brain where new neurons are continuously produced in adulthood. Certain insults such as epileptic seizures and ischemia are known to enhance the rate of neuronal production. We analyzed this phenomenon using the temporary occlusion of the two carotid arteries combined with arterial hypotension as a method to induce ischemia in rats. We measured the rate of cell production and their state of differentiation with a mitotic indicator, bromodeoxyuridine (BrdU), in combination with the immunohistochemical detection of neuronal markers. One week after the ischemic episode, the cell production in dentate gyrus was increased two- to threefold more than the basal level seen in control animals. Two weeks after ischemia, over 60% of these cells became young neurons as determined by colabeling with BrdU and a cytoplasmic protein (CRMP-4) involved in axonal guidance during development. Five weeks after the ischemia, over 60% of new neurons expressed calbindin, a calcium-binding protein normally expressed in mature granule neurons. In addition to more cells being generated, a greater proportion of all new cells remained in the differentiated but not fully mature state during the 2- to 5-week period after ischemia. The maturation rate of neurons as determined by the calbindin labeling and by the rate of migration from a proliferative zone into the granule cell layer was not changed when examined 5 weeks after ischemia. The results support the hypothesis that survival of dentate gyrus after ischemia is linked with enhanced neurogenesis. Additional physiological stimulation after ischemia may be exploited to stimulate maturation of new neurons and to offer new therapeutic strategies for promoting recovery of neuronal circuitry in the injured brain. 相似文献
43.
Selberg O McMillan DC Preston T Carse H Shenkin A Burns HJ 《Clinical nutrition (Edinburgh, Scotland)》1990,9(3):150-156
Palmitate turnover in weight-stable control subjects (n = 4) and weight-losing patients with progressive malignant disease (n = 4) has been determined. Measurements were made after an overnight fast and during glucose infusion (3.5 mg/kg/min). Turnover rates were calculated from plateau isotopic enrichment of palmitate in plasma during a continuous infusion of 1-13C palmitate. Palmitate turnover was higher in the cancer group before (180%) and during glucose loading (170%) compared with the control group. Palmitate turnover was reduced during glucose administration by approximately 34% in both groups. Plasma concentration of insulin was decreased and of cortisol was increased in the cancer group compared with the control group before and during glucose infusion. We conclude that cancer patients with weight loss have increased rates of fatty acid turnover indicative of enhanced mobilisation of body fat stores. Altered plasma concentrations of insulin and cortisol may mediate this effect. Nonetheless, even at more advanced stages of cachexia cancer patients have normal control mechanisms for inhibiting fatty acid turnover following administration of carbohydrate. 相似文献
44.
45.
Preston RT 《Radiology management》1994,16(1):20-22
Prior to an innovative consolidation, it could take two hours to complete outpatient testing at the Ephraim McDowell Medical Center in Danville, Kentucky. Outpatients were subjected to time-consuming journeys through the hospital to find different departments. Frequently, they lost their way and entered restricted areas of the hospital. A quality improvement (QI) team was formed to implement a consolidation plan that had been developed by the radiology administrator and approved by upper management. In the end, three outpatient services were integrated into one location, greatly simplifying the process for patients and increasing efficiency for all. The consolidation was accomplished by reconfiguring existing space. It was open for service just two months after the QI team was formed. Outpatient testing can now be completed in 30 to 40 minutes. 相似文献
46.
A young boy presented with an uncommon finding of impaction of upper right central incisor and transposition of canine and lateral incisor on the same side. Esthetic management of his cosmetic problem which included fixed appliance therapy followed by light cure restorations is discussed.KEY WORDS: Impaction, Transposition 相似文献
47.
An Unexpected Change in DXA Calibration not Detected by Routine Quality Control Checks 总被引:2,自引:0,他引:2
G. M. Blake N. G. Preston R. Patel R. J. M. Herd I. Fogelman 《Osteoporosis international》1999,9(2):115-120
Since its commercial introduction a decade ago, the technique of dual-energy X-ray absorptiometry (DXA) has been widely recognized
as a useful and sensitive method of measuring changes in bone mineral density (BMD) at selected sites in the skeleton such
as the spine and proximal femur. Because of their high precision and stable calibration, DXA scanners are frequently used
in clinical trials to evaluate new treatments for osteoporosis. Quality assurance procedures based on regular scanning of
phantoms are widely adopted in such trials, and continuity of the phantom BMD measurements is generally believed to ensure
continuity in the in-vivo calibration. We report a change in calibration of a DXA scanner that occurred during a clinical
trial where the calibration shift was different for the spine and femur sites and was not predicted or explained by the standard
quality control procedures using phantoms. However, we show that provided patients enrolled in studies are thoroughly randomized
and the statistical analysis is confined to the differences between the treated and control groups, then the effects of such
calibration shifts on conclusions regarding the efficacy of treatment are considerably smaller than the random statistical
errors.
Received: 12 February 1998 / Accepted: 20 May 1998 相似文献
48.
Biphasic opening of the blood-brain barrier following transient focal ischemia: effects of hypothermia 总被引:6,自引:0,他引:6
Huang ZG Xue D Preston E Karbalai H Buchan AM 《The Canadian journal of neurological sciences. Le journal canadien des sciences neurologiques》1999,26(4):298-304
OBJECTIVE: Tracer constants (Ki) for blood-to-brain diffusion of sucrose were measured in the rat to profile the time course of blood-brain barrier injury after temporary focal ischemia, and to determine the influence of post-ischemic hypothermia. METHODS: Spontaneously hypertensive rats were subjected to transient (2 hours) clip occlusion of the right middle cerebral artery. Reperfusion times ranged from 1.5 min to 46 hours, and i.v. 3H-sucrose was circulated for 30 min prior to each time point (1 h, 4 h, 22 h, and 46 h; n = 5-7 per time point). Ki was calculated from the ratio of parenchymal tracer uptake and the time-integrated plasma concentration. Additional groups of rats (n = 7-8) were maintained either normothermic (37.5 degrees C) or hypothermic (32.5 degrees C or 28.5 degrees C) for the first 6 hours of reperfusion, and Ki was measured at 46 hours. RESULTS: Rats injected after 1.5-2 min exhibited a 10-fold increase in Ki for cortical regions supplied by the right middle cerebral artery (p < 0.01). This barrier opening had closed within 1 to 4 hours post-reperfusion. By 22 hours, the blood-brain barrier had re-opened, with further opening 22 and 46 hours (p < 0.01), resulting in edema. Whole body hypothermia (28 degrees C-29 degrees C) during the first six hours of reperfusion prevented opening, reducing Ki by over 50% (p < 0.05). CONCLUSIONS: Transient middle cerebral artery occlusion evokes a marked biphasic opening of the cortical blood-brain barrier, the second phase of which causes vasogenic edema. Hypothermic treatment reduced infarct volume and the late opening of the blood-brain barrier. This opening of the blood-brain barrier may enhance delivery of low permeability neuroprotective agents. 相似文献
49.
Discusses an audit of communications between doctors and other professional groups in a National Health Services trust hospital. The project was undertaken as a result of senior management's perception that there were problems regarding the interface between professionals and junior doctors particularly, and that these have a potentially detrimental impact on patient care. The aim of the study was to improve the work environment of medical practitioners and professional staff by researching the factors affecting communication and the sources of conflict which exist between the groups. Describes the methodology and provides an overview of the main findings grouped into themes. A large number of recommendations for change have been made to the hospital concerning systems, procedures, structures, training and inter-professional boundaries. Implementation of some of these recommendations has taken place already. Full evaluation of their impact is yet to be determined. 相似文献
50.
Michael Phillips MRCP Preston Hensley PhD Richard A. Baiter MD Stanley L. Cohan MD 《Alcoholism, clinical and experimental research》1984,8(3):293-296
An improved method is described for the collection of breath for the subsequent assay of acetaldehyde and other volatile components. Breath is collected in a Pyrex gas-collecting tube sealed at both ends with Teflon taps. Prior to collection or assay of the samples, this tube is heated to 72 degrees C; breath is sampled for assay by piercing a rubber septum on a sideport with the needle of a similarly heated gas-tight syringe, and injected into a gas chromatograph (GC). The advantages of this system are: (1) Avoidance of the artefacts encountered in the assay of acetaldehyde in the blood; (2) suitability for sample collection at a site remote from the GC laboratory; (3) avoidance of sample loss by leakage, contamination, or partitioning into water condensed from breath; and (4) compatibility with a "nondedicated" GC lacking any special gas-collecting circuitry. A typical study of a normal human volunteer is described, demonstrating the rise and fall of the concentration of acetaldehyde and ethanol in the breath following the ingestion of an oral dose of ethanol. 相似文献