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31.
William R. Reinus M.D. Franz J. Wippold II M.D. Kavita K. Erickson M.D. 《Emergency radiology》1994,1(2):81-84
We studied clinical predictors of cranial computed tomography (CT) abnormalities in patients with acute or acutely worsened
headache. Data were collected from chart review of 333 consecutive patients presenting to an emergency department and who
were clinically selected for cranial CT. Patients with a positive neurologic examination were at 10.7 times greater risk for
a positive CT than the rest of the sample (p<1.5 – 10−10). Using only neurologic examination to select patients for CT would have missed 30.3% of the positive scans. The amnesia,
depressed sensorium, and hypertension variables had CT yields approximating 10% or greater even in the presence of a negative
neurologic examination. Together with a positive neurologic examination, these variables detected 87.9% of the patients in
this sample with positive scans; their absence had a negative predictive value of 98.0%. Of the four patients with positive
scans who would have been missed using this strategy, one was discharged directly from the emergency department anyway and
the other three developed positive neurologic examinations within 24 hours. One died of causes unrelated to the intracranial
pathology. Positive neurologic examination, hypertension, history of amnesia, or a depressed sensorium provide reasonable
initial guidelines to select for CT patients with an acute headache. 相似文献
32.
The anaesthetic management of children with glycogen-storage disease type lia (Pompe’s disease) presents a variety of challenges. A modification of a femoral nerve block, the inguinal paravascular block, as described by Winnie, was used in conjunction with intravenous ketamine to provide anaesthesia for a diagnostic muscle biopsy in a 5.5-month-old infant with Pompe’s disease. A peripheral nerve stimulator was used to locate the femoral nerve in lieu of eliciting a paraesthesia. 相似文献
33.
34.
S Sugahara M Rosen C J Juniper K R Johnston R L Davies 《European journal of anaesthesiology》1992,9(4):341-346
A method has been developed to compare gastrointestinal (GI) transit time after intrathecal (i.t.) drug injection in the rat. Each animal had a catheter implanted in the i.t. space. Eight rats, on three separate occasions, had either i.t. morphine 16 micrograms kg-1 (in 50 microliters) or intraperitoneal (i.p.) morphine (0.1%) 7.5 mg kg-1 or i.t. saline (50 microliters). The dose of morphine was the ED50 for analgesia by each route. After halothane and oxygen anaesthesia, 10 steel balls and 1 ml of contrast medium were placed into the stomach, the whole procedure being completed within 5 min. Radiographs were taken at 5 min, 3, 6 and 24 h, and the number of balls in the stomach, small and large intestine were counted. The inhibitory effect of i.t. or i.p. morphine on gut motility caused an equally significant delay at 6 h. In a separate series of eight rats the delay by i.t. morphine could be completely antagonized by i.p. naloxone 1 mg kg-1. Thus, i.t. morphine in an analgesic dose even though smaller than the i.p. dose has a similar inhibitory effect on GI tract motility in the rat. This method would enable comparisons on GI transit to be made between a variety of intrathecally administered drugs. 相似文献
35.
Seung Min Lee Seung Kyung Hann Soo II Chun Seung Hung Lee Yoon-Kee Park 《The Journal of dermatology》1994,21(2):106-110
A 25-year-old female has had brown to erythematous telangiectatic patches and grouped papules on her face, neck, arm, and trunk since childhood following B.C.G. vaccination. Histopathologically, the lesions consisted of hyperkeratosis, slight acanthosis, tuberculoid granulomas with some Langerhans type giant cells in the mid-dermis. Although various forms of cutaneous tuberculosis after B.C.G. vaccination have been reported, it was difficult for us to assign the patient's skin lesion to any specific disease entity. Remission of her cutaneous lesions occurred clinically and histopathologically after treatment with isoniazid and rifampin. 相似文献
36.
A study was undertaken to determine if cis-DDP and its second generation derivatives produced effects on mouse liver mitochondria, and if any of the observed effects could be correlated with the nephrotoxicity of the drugs. Although changes were observed in mitochondrial morphology, enzyme activity, Ca2+ influx, terbium binding and surface potential, no specific effect was correlated with nephrotoxicity. cis-DDP produced marked changes in mitochondrial morphology; electron probe analysis showed binding of the drug to the mitochondria. Inhibition of complex I and II activity of the respiratory chain and an ionic-strength-dependent effect on Tb3+ (a Ca2+ analogue) fluorescence were observed. The non-nephrotoxic derivatives, CHIP and tetraplatin, also produced significant changes in morphology. Treatment with these derivatives also produced decreases in mitochondrial enzyme activity, but the effect on terbium binding had an ionic-strength dependence which was inverse to that observed with cis-DDP. The tetravalent compounds also had a notable effect on mitochondrial surface potential. Carboplatin had an effect on morphology and Ca2+ influx and it inhibited the respiratory enzymes, although in a manner different from that observed with cis-DDP. Carboplatin had a minimal effect on terbium binding. It is evident that if the platinum drugs enter a cell to exert their action at the nuclear level, they will also depress mitochondrial function. The observed effects did not correlate with nephrotoxicity but, since all four compounds significantly altered mitochondrial structure and function, they may be related to the cytotoxicity of the drug. 相似文献
37.
38.
Dynamic rotation is a computer-controlled therapy technique utilizing an automated multileaf collimator in which the radiation beam shape changes dynamically as the treatment machine rotates about the patient so that at each instant the beam shape matches the projected shape of the target volume. In simple dynamic rotation, the dose rate remains constant during rotation. For optimized dynamic rotation, the dose rate is varied as a function of gantry angle. Optimum dose rate at each gantry angle is computed by linear programming. Wedges can be included in the optimized dynamic rotation therapy by using additional rotations. Simple and optimized dynamic rotation treatment plans, with and without wedges, for a pancreatic tumor have been compared using optimization cost function values, normal tissue complication probabilities, and positive difference statistic values. For planning purposes, a continuous rotation is approximated by static beams at a number of gantry angles equally spaced about the patient. In theory, the quality of optimized treatment planning solutions should improve as the number of static beams increases. The addition of wedges should further improve dose distributions. For the case studied, no significant improvements were seen for more than 36 beam angles. Open and wedged optimized dynamic rotations were better than simple dynamic rotation, but wedged optimized dynamic rotation showed no definitive improvement over open beam optimized dynamic rotation. 相似文献
39.
H. R. Rosen W. Feil G. Novi G. Zöch S. Dahlberg R. Schiessel 《International journal of colorectal disease》1994,9(4):184-186
Continence following the gracilis stimulated neosphincter reconstruction after total rectal excision is inferior to that obtained in the presence of an intact anal canal. We describe a modification of the alpha loop in which the tendon is brought through the belly of the gracilis muscle. The results in three patients are presented.
Résumé La reconstruction sphinctérienne après excision totale du rectum au moyen d'un néosphincter fait d'un muscle gracilis stimulé donne des résultats sur le plan de la continence inférieurs à ceux obtenus en présence d'un canal anal intact. Nous décrivons une modification de l'anse alpha dans laquelle le tendon est fixé après avoir traversé la sangle de muscle gracilis. Les résultats de trois patients sont rapportés.相似文献
40.
Depressed patients were interviewed at two different severity levels in the course of their illness about both problematic and neutral topics, and their speech behavior was analyzed in terms of speech activity and silences. Lowered speech activity and increased silences occurred at higher severity levels and also during problematic communication content, suggesting the mediation of cognitive factors as postulated by Beck's cognitive model of depression. 相似文献