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42.
D A Keith 《Current opinion in dentistry》1991,1(4):503-506
Surgical intervention may be necessary for some patients with specific pathology or derangement of the temporomandibular joint as part of an overall management protocol. The current literature discusses the efficacy of arthroscopy, the treatment of the difficult problem of ankylosis, and the use of implants and autogenous and allogenic materials to replace the disk. 相似文献
43.
Bill J Gurley Ashley Swain Gary W Barone D Keith Williams Philip Breen C Ryan Yates Leslie B Stuart Martha A Hubbard Yudong Tong Sreekhar Cheboyina 《Drug metabolism and disposition》2007,35(2):240-245
Phytochemical-mediated modulation of P-glycoprotein (P-gp) and other drug transporters may give rise to many herb-drug interactions. Serial plasma concentration-time profiles of the P-gp substrate, digoxin, were used to determine whether supplementation with goldenseal or kava kava modified P-gp activity in vivo. Twenty healthy volunteers were randomly assigned to receive a standardized goldenseal (3210 mg daily) or kava kava (1227 mg daily) supplement for 14 days, followed by a 30-day washout period. Subjects were also randomized to receive rifampin (600 mg daily, 7 days) and clarithromycin (1000 mg daily, 7 days) as positive controls for P-gp induction and inhibition, respectively. Digoxin (Lanoxin, 0.5 mg) was administered p.o. before and at the end of each supplementation and control period. Serial digoxin plasma concentrations were obtained over 24 h and analyzed by chemiluminescent immunoassay. Comparisons of area under the curve (AUC)((0-3)), AUC((0-24)), C(max,) CL/F, and elimination half-life were used to assess the effects of goldenseal, kava kava, rifampin, and clarithromycin on digoxin pharmacokinetics. Rifampin produced significant reductions (p < 0.01) in AUC((0-3)), AUC((0-24)), CL/F, t(1/2), and C(max), whereas clarithromycin increased these parameters significantly (p < 0.01). With the exception of goldenseal's effect on C(max) (14% increase), no statistically significant effects on digoxin pharmacokinetics were observed following supplementation with either goldenseal or kava kava. When compared with rifampin and clarithromycin, supplementation with these specific formulations of goldenseal or kava kava did not appear to affect digoxin pharmacokinetics, suggesting that these supplements are not potent modulators of P-gp in vivo. 相似文献
44.
Balanced analgesia (an opioid and a nonsteroidal anti-inflammatory agent) after hysterectomy often leads to better postoperative pain outcomes. Researchers compared post-hysterectomy patients who received balanced analgesia with those who received only morphine patient-controlled analgesia, and their relationship with pain scores, ambulation, and hospital length of stay. 相似文献
45.
Enrico G Caiani Eran Toledo Peter MacEneaney Keith A Collins Roberto M Lang Victor Mor-Avi 《Journal of cardiovascular magnetic resonance》2004,6(3):619-625
BACKGROUND: Cardiac magnetic resonance (MR) images are often reviewed by non-cardiologists who are not trained in the interpretation of regional left ventricular (LV) function. We hypothesized that the use of still-frame parametric MR images of wall motion could aid in the assessment of regional LV function. METHODS: Dynamic, electrocardiogram-gated, steady-state free precession (FIESTA) short-axis images were obtained in 6 to 10 slices in 18 consecutive patients. Each loop was used to automatically generate a still-frame image, in which each pixel is assigned a value equal to the amplitude of cyclic variation in local intensity, resulting in higher intensity in pixels that change between blood and tissue during the cardiac cycle. The dynamic images were reviewed by an expert cardiologist who provided gold standard grades for regional wall motion and by four radiologists. Then the radiologists reviewed and graded the same MR images in combination with parametric images. Grades assigned to each segment in the two sessions were compared with the gold standard. RESULTS: According to expert interpretation, 6 patients had normal wall motion, and 12 had wall motion abnormalities. Parametric images showed a bright band in the area spanned by endocardial motion, with reduced brightness and thickness in areas of hypokinesis. The agreement between the radiologists' grades and the gold standard significantly improved by adding parametric images (from 77% to 81%), which also resulted in reduced interobserver variability (from 52% to 33%). CONCLUSIONS: Still-frame parametric images aid in the assessment of regional wall motion by non-cardiologists who are required to interpret cardiac images. 相似文献
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Rats undergoing extinction of lever-pressing for food after the attenuation of an external feedback for this behavior exhibit excessive lever-pressing unaccompanied by an attempt to collect a reward. This behavior may be analogous to the excessive and unreasonable behavior seen in obsessive-compulsive disorder. In the present study, we tested the hypothesis that the compulsive behavior induced by signal attenuation is mediated via D(1) rather than D(2) receptors. Administration of 0.005, 0.01 and 0.03 mg/kg of the D(1) antagonist SCH 23390 reduced the number of compulsive lever-presses without affecting the number of lever-presses followed by an attempt to collect a reward. In contrast, administration of 0.005, 0.01, 0.024, 0.036 and 0.05 of the D(2) antagonist haloperidol dose-dependently decreased both types of lever-presses. In addition, haloperidol at doses that decreased lever-pressing in the post-training signal attenuation procedure (0.036 and 0.05 mg/kg) had a similar effect in regular extinction, whereas an SCH 23390 dose that decreased compulsive lever-pressing in the post-training signal attenuation procedure (0.01 mg/kg) had no effect on regular extinction. On the basis of electrophysiological data on the response of dopamine neurons to the omission of an expected reward, these results were interpreted as suggesting that compulsive lever-pressing depends on a phasic decrease in the stimulation of D(1) receptors. The implications of these results for the pathophysiology and treatment of obsessive-compulsive disorder are discussed. 相似文献
49.
Javier Alegre-López José Cordero-Guevara José L. Alonso-Valdivielso Julia Fernández-Melón 《Osteoporosis international》2005,16(7):729-736
Hip fracture results in excess mortality and functional disability. This study sought to identify predictors of mortality and limited functional ability 1 year after hip fracture. We conducted a 1-year follow-up of a prospective population-based inception cohort of 218 hip fracture patients who had been consecutively admitted and discharged from hospital during the previous year. Mortality was observed to be independently associated with poor mental status (relative risk [RR]=6.96; 95% confidence interval [95% CI], 1.73–28.00), prefracture limited functional ability (RR=4.35; 95% CI, 1.32–14.36), institutionalized disposition at discharge (RR=2.92; 95% CI, 1.02–8.38), and male gender (RR=2.44; 95% CI, 1.01–5.93). Independent predictors of limited functional ability were prefracture functional disability (RR=34.14; 95% CI, 3.13–372.33), poor mental status (RR=9.71; 95% CI, 1.57–59.82), age >80 years (RR=4.03; 95% CI, 1.48–11.00), and female gender (RR=3.57; 95% CI, 0.08–0.98). On discharge, special attention and care should thus be given to all patients displaying any of the above predictive factors. 相似文献
50.
Keith D. Lindor 《Hepatology research》2007,37(S3):S474-S477
Primary sclerosing cholangitis (PSC) is a chronic cholestatic liver disease of unknown etiology that is frequently associated with inflammatory bowel disease. It is characterized by diffuse inflammation and fibrosis of the biliary tree, and it usually leads to biliary cirrhosis and portal hypertension. PSC is most commonly diagnosed with endoscopic retrograde cholangiopancreatography, although magnetic resonance cholangiography (MRC) is rapidly emerging as a first choicediagnostic test. MRC has the advantage of being non-invasive, does not require radiation, and is cost-effective in that it does not carry the risk of pancreatitis associated with retrograde studies. 2 Percutaneous cholangiography is seldom performed anymore. 相似文献