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排序方式: 共有1033条查询结果,搜索用时 78 毫秒
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The efficacy of three different regimens of the 21-aminosteroid U74006F in counteracting the neurological damage after spinal cord compression causing paraparesis in rats was investigated. Three groups of ten animals each were given totally 6 mg/kg of U74006F in different regimens beginning one hour after injury (A: bolus doses of 1.5 mg/kg at 1, 4, 7 and 10 hours; B: bolus of 1.5 mg/kg at 1 hour and 4.5 mg/kg as an infusion over the next 9 hours; and C: infusion alone, 6 mg/kg, given between 1 and 10 hours after trauma). Two groups of ten animals each received vehicle alone in administration modes comparable to those of the U74006F treated animals. The motor function was assessed daily on the inclined plane. On day one, the capacity angle had decreased from about 62 degrees preoperatively to 28-30 degrees in the two vehicle-treated groups and in group C. In these groups there was a similar improvement in neurological function and on day 9 the capacity angles were 49-55 degrees. In groups A and B, both of which received a bolus dose of U74006F at 1 hour, the neurological outcome improved on day one with capacity angles of 38-40 degrees. The difference in neurological function between the animals given U74006F as bolus doses and those given vehicle alone persisted over the entire observation span until day 9. The data suggest that early treatment with a bolus dose seems to be required in order to obtain an effect of U74006F on neurological recovery. 相似文献
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G E Stokker A W Alberts P S Anderson E J Cragoe A A Deana J L Gilfillan J Hirshfield W J Holtz W F Hoffman J W Huff 《Journal of medicinal chemistry》1986,29(2):170-181
The syntheses of a series of 7-(3,5-disubstituted [1,1'-bephenyl]-2-yl)-3,5-dihydroxy-6-heptenoic acids and their lactones are reported. Intrinsic 3-hydroxy-3-methylglutaryl-coenzyme A reductase inhibitory activity is enhanced markedly when the biphenyl moiety is substituted by chloro or methyl groups at positions 3 and 5 and a fluoro group at position 4'. These substitutions, followed by resolution, provided compounds 100(+) and 110(+) with 2.8 times the intrinsic inhibitory activity of compactin. Compound 100(+) was shown to possess the same chirality in the lactone ring as compactin by single-crystal X-ray crystallography. 相似文献
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Delayed Gastric Emptying after Laparoscopic Anterior Highly Selective and Posterior Truncal Vagotomy
Martin Tobi M.B. Ch.B. Todd Holtz M.D. John Carethers M.D. Chung Owyang M.D. 《The American journal of gastroenterology》1995,90(5):810-811
We describe a case of gastroparesis after laparoscopic highly selective anterior and posterior truncal vagotomy in a 30-yr-old male with gastric ulcer disease. Motility studies confirmed the diagnosis, and a pancreatic polypeptide sham feeding study suggested that a complete vagotomy may have been inadvertently performed. The experience with this procedure in gastric ulcer disease is extremely limited; review of the literature of laparoscopic highly selective vagotomy describes only two cases with delayed gastric emptying as defined by radiological examination. In view of the paucity of reports, caution is warranted, and this procedure should be undertaken only in the setting of a controlled trial. 相似文献
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Brandon JC; Teplick SK; Haskin PH; Sammon JK; Muhr WF; Hofmann AF; Gambescia RA; Zitomer N 《Radiology》1988,166(3):665-667
The authors describe their experience with methyl tertiary butyl ether (MTBE) in a larger series of patients than previously reported in order to acquaint physicians with both its effectiveness for dissolution of common bile duct calculi and the limitations of its use. Ten patients with 13 biliary calculi underwent percutaneous stone dissolution treatment with the experimental cholesterol solvent, MTBE. Three stones completely dissolved within 30 minutes, seven were reduced in size, and three were visibly unaffected. All stones not completely dissolved were easily extracted by means of a stone basket except for one in a patient taken to surgery. Although MTBE perfusion is an effective technique for management of biliary calculi, practitioners should be aware that its use is quite time consuming and its odor difficult to control. 相似文献
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Limited-field-of-view radio-frequency receiver antennas provide improved near-field sensitivity for magnetic resonance imaging by decreasing the antenna volume. The Helmholtz-type surface coil, consisting of two flat rings, is an organ-encompassing antenna that takes advantage of this principle to yield an improved signal-to-noise ratio (S/N). The coil was tested in a group of 50 patients and 16 healthy volunteers. Images obtained with the Helmholtz coil demonstrated quantitatively superior S/N of 2.2-fold or greater than that of comparison body coil images, as well as qualitatively superior anatomic resolution. 相似文献
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M L Schiebler B C Yankaskas C Tempany P Holtz E Zerhouni 《Investigative radiology》1992,27(8):575-577
OBJECTIVES. The authors compared the two most common presurgical tests now used for the preoperative staging of adenocarcinoma of the prostate, prostate-specific antigen (PSA) and magnetic resonance imaging (MRI). METHODS. One hundred consecutive radical retropubic prostatectomy patients were imaged at 1.5 Tesla before surgery with routine T1-weighted and T2-weighted transaxial images. The images were analyzed by two experienced radiologists for evidence of extracapsular disease. Radiologists rated each gland on a scale of 0 to 100 for the percentage likelihood of extracapsular disease based on its MRI appearance. Receiver operator characteristic (ROC) curves were plotted, and areas were calculated for the two radiologists and the preoperative PSA values. RESULTS. Comparison of the areas of the ROC curves generated from the two radiologists and those from the preoperative PSA values showed no statistical difference. CONCLUSIONS. In this series, radiologic interpretation of body coil MRI studies in those patients chosen for a radical retropubic prostatectomy was no better in staging adenocarcinoma of the prostate than simply using the preoperative PSA values. 相似文献
9.
A A Kühn P Grosse K Holtz P Brown B-U Meyer A Kupsch 《Clinical neurophysiology》2004,115(8):1786-1795
OBJECTIVE: Multiple system atrophy (MSA), progressive supranuclear palsy (PSP), and corticobasal-ganglionic degeneration (CBGD) are all clinically characterized by an akinetic-rigid syndrome together with a variety of additional signs. We hypothesised that these atypical parkinsonian syndromes (APS) will show distinctive patterns in their motor output upon transcranial magnetic stimulation (TMS) due to their different underlying anatomico-functional deficits. METHODS: We performed single and paired-pulse TMS and assessed inhibitory and excitatory response parameters from the first dorsal interosseus muscles in 13 patients with MSA, 18 with PSP, 13 with CBGD, 15 patients with Parkinson's disease and 17 healthy subjects. RESULTS: PSP and MSA patients had significantly enlarged response amplitudes at rest, reduced intracortical inhibition (ICI) and prolonged ipsi- and contralateral silent periods, whereas CBGD patients showed significantly increased motor thresholds, smaller response amplitudes at rest, shortened contralateral silent period, reduced transcallosal inhibition and a reduced ICI. In 22% of APS patients ipsilateral motor responses occurred in upper limb muscles irrespective of the underlying disease. CONCLUSIONS: Our results indicate that motor cortex disinhibition is predominant in patients with PSP and MSA. In CBGD more severe neuronal cell loss in the motor cortex itself may lead to hypoexcitability of corticospinal and transcallosal pathways. 相似文献
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