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61.
S E Campbell C D Phillips E Dubovsky W S Cail R A Omary 《AJNR. American journal of neuroradiology》1995,16(7):1385
PURPOSETo determine whether plain films alone are sufficient in the evaluation of stability of simple wedge-compression fractures of the lumbar spine.METHODSPlain films and CT scans of 53 consecutive patients seen during a 2-year period with lumbar spine fractures were retrospectively reviewed. Six readers blinded to the CT diagnosis independently read each patient''s plain films. Plain-film findings were scored on a five-point graded response scale using criteria proposed by Gehweiler and Daffner. In addition, a fracture was considered to be possibly unstable if there was involvement of more than one vertebral level or greater than 50% loss of anterior vertebral body height. CT findings represented the standard for comparison. CT scans were independently evaluated by three additional readers. Two-column involvement, middle-column involvement alone but with retropulsion, multiple-level involvement, or greater than 50% loss of vertebral height indicated potential instability.RESULTSFor 14 stable and 39 potentially unstable lumbar spine fractures, the pooled (mean) plain-film negative predictive value for detection of potentially unstable fractures was 0.62 (95% confidence interval, 0.53 to 0.70), with a sensitivity of 0.83 (95%, confidence interval; 0.78 to 0.87), and specificity of 0.80 (95% confidence interval, 0.70 to 0.87).CONCLUSIONPlain films are not adequate for determining stability of lumbar spine fractures. 相似文献
62.
Body pain and treatment response in late-life depression. 总被引:2,自引:0,他引:2
Jordan F Karp Debra Weiner Karen Seligman Meryl Butters Mark Miller Ellen Frank Jacqueline Stack Benoit H Mulsant Bruce Pollock Mary Amanda Dew David J Kupfer Charles F Reynolds 《The American journal of geriatric psychiatry》2005,13(3):188-194
OBJECTIVE: The authors investigated the influence of body pain on 1) time to treatment response and 2) suicidal ideation, in late-life depression. They hypothesized that higher levels of body pain would predict a longer time to and lower likelihood of response, and increased levels of suicidal ideation. METHODS: Subjects (N=187) were older adult outpatients (age > or =69 years), with current episodes of major depression, who were openly treated with paroxetine up to 40 mg daily and weekly interpersonal psychotherapy. Response was defined as 3 consecutive weeks of Hamilton Rating Scale for Depression at < or =10. Body pain was measured with the Bodily Pain Index of the SF-36 quality-of-life assessment. Authors used survival-analysis models on the responder sample to test the effect of body pain on response, after controlling for severity of depression. RESULTS: Overall response rate was 75.4%. Nonresponders reported more severe pain at baseline. After covarying for severity of baseline depression, no effect was found for physical pain on time-to-response or degree of suicidality. Bodily pain remained stable during acute treatment for responders, independent of depression response to combination psychotherapy and antidepressant treatment. CONCLUSIONS: Older adult patients with higher levels of physical pain can still respond to antidepressant treatment; however, reported bodily pain may be associated with a more difficult-to-treat depression. 相似文献
63.
LM985 has been shown previously to hydrolyse to flavone acetic acid (LM975) in mouse plasma and to produce significant anti-tumour effects in transplantable mouse colon tumours (MAC). It has undergone Phase I clinical trials and dose limiting toxicity was acute reversible hypotension. Substantially higher doses of LM975 can be given clinically without dose limiting toxicity. We have investigated the activity of LM975 against a panel of MAC tumours and also the in vitro cytotoxicity of both LM985 and LM975 in two cell lines derived from MAC tumours. LM985 is considerably more cytotoxic than LM975 in vitro but increased length of exposure to LM975 results in improved activity. Single in vivo injection of LM975 showed no activity against the ascitic tumour MAC 15A, moderate activity against the s.c. poorly differentiated tumour MAC 13 and produced a significant growth delay in the well differentiated MAC 26. These latter responses were considerably enhanced by repeated injection 7 days later. Pharmacokinetic studies in mice following i.p. injection of LM985 demonstrated rapid degradation of LM985 to LM975 in the peritoneum. Length of exposure as well as drug concentration appear important factors in determining anti-tumour responses. 相似文献
64.
Ernesto Pasquini Vittorio Sciarretta Giorgio Frank Cosetta Cantaroni Giovanni Carlo Modugno Diego Mazzatenta Giovanni Farneti 《Otolaryngology--head and neck surgery》2004,131(3):180-186
OBJECTIVE: The endoscopic approach can be successfully employed for the treatment of benign tumors such as fibroosseus and vascular lesions, pleomorphic adenomas, gliomas, and schwannomas. STUDY DESIGN AND SETTING: Nineteen patients diagnosed with benign tumors of the nasal cavity and paranasal sinuses and treated using an endoscopic approach were retrospectively reviewed. The endoscopic approach was used exclusively in 15 cases and was associated with an external approach in 4 cases (due to an intracranial extension of the tumor in 3 patients and its location at the level of the anterior wall of the frontal sinus in the last case). RESULTS: The resection of the lesions was radical in 18 patients and subtotal in 1 case. The mean follow-up was 27 months and only 1 recurrence (5%) was observed in the juvenile angiofibroma group 20 months postoperatively. CONCLUSION: and significance In selected cases, endoscopic surgery can be considered an effective treatment for the resection of benign tumors involving the sinonasal tract. 相似文献
65.
66.
High-resolution myocardial perfusion mapping in small animals in vivo by spin-labeling gradient-echo imaging. 总被引:1,自引:0,他引:1
Frank Kober Isabelle Iltis Marguerite Izquierdo Martine Desrois Danielle Ibarrola Patrick J Cozzone Monique Bernard 《Magnetic resonance in medicine》2004,51(1):62-67
An ECG and respiration-gated spin-labeling gradient-echo imaging technique is proposed for the quantitative and completely noninvasive measurement and mapping of myocardial perfusion in small animals in vivo. In contrast to snapshot FLASH imaging, the spatial resolution of the perfusion maps is not limited by the heart rate. A significant improvement in image quality is achieved by synchronizing the inversion pulse to the respiration movements of the animals, thereby allowing for spontaneous respiration. High-resolution myocardial perfusion maps (in-plane resolution=234 x 468 microm2) demonstrating the quality of the perfusion measurement were obtained at 4.7 T in a group of seven freely breathing Wistar-Kyoto rats under isoflurane anesthesia. The mean perfusion value (group average +/- SD) was 5.5 +/- 0.7 ml g(-1)min(-1). In four animals, myocardial perfusion was mapped and measured under cardiac dobutamine stress. Perfusion increased to 11.1 +/- 1.9 ml g(-1)min(-1). The proposed method is particularly useful for the study of small rodents at high fields. 相似文献
67.
M D Stonard P G Phillips J R Foster M G Simpson E A Lock 《Clinica chimica acta; international journal of clinical chemistry》1986,160(2):197-203
The concentration of renal alpha 2U-globulin increased in a dose-dependent manner in adult male but not female rats which received a single dose of 2,2,4-trimethylpentane (TMP). After administration of a single dose of 12 mmol TMP/kg to adult male rats, the renal concentration of alpha 2U-globulin reached a peak at 48 hours and returned to near background level after 7 days. These changes in renal alpha 2U-globulin concentration were closely paralleled by changes in renal hyaline droplet formation. Renal alpha 2U-globulin and hyaline droplets were absent in normal pre-puberty male rats, and neither could be stimulated by a single dose of TMP. alpha 2U-Globulin was localised in the renal cortex of adult male rats, in particular the S2 segment of the proximal tubule. A greater staining intensity due to alpha 2U-globulin was seen in the S2 and adjacent segments after a single dose of TMP. A strong association is suggested between the presence of renal hyaline droplets and the occurrence of alpha 2U-globulin. 相似文献
68.
69.
70.
The effect of time of day of drug administration on triazolam pharmacokinetics was studied in ten healthy men. In a randomized, two-way, crossover investigation, each subject received one 0.5 mg triazolam tablet either in the morning (7 AM) or evening (10 PM). Blood samples were obtained immediately before dosing and at selected times up to 12 hours after dosing. Triazolam plasma concentrations were determined by gas chromatography with electron capture detection. Psychomotor performance tests, including digit symbol substitution, card sorting by suits, and card sorting by fours, were administered, and the subjects' sedation was rated before drug and at two, ten, and 12 hours after drug administration. In addition, anterograde amnesia was assessed by showing objects to subjects two hours after dosing and testing aided and unaided recall at ten hours following administration. Triazolam's apparent elimination half-life after evening administration was significantly longer than after daytime ingestion (3.77 hr vs. 2.94 hr, P less than .05). There was no difference between times of dosing in total oral clearance or apparent volume of distribution. The absorption of triazolam was slower after evening administration, with an absorption half-life of 21.9 vs 13.3 minutes after daytime dosing. Performance decrements were significantly greater two hours after dosing in evening than in the daytime, but anterograde amnesia was more pronounced after daytime dosing. There was no effect on psychomotor performance at ten or 12 hours after administration in daytime or evening. These results indicate temporal variation in triazolam absorption and elimination.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献