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11.
Perfusion is a crucial physiological parameter for tissue function. To obtain perfusion-weighted images and consequently to measure cerebral blood flow (CBF), a newly developed flow-sensitive alternating inversion recovery (FAIR) technique was used. Dependency of FAIR signal on inversion times (TI) was examined; signal is predominantly located in large vessels at short TI, whereas it is diffused into gray matter areas at longer TI. CBF of gray matter areas in the human brain is 71 ± 15 SD ml/100 g/min (n = 6). In fMRI studies, micro- and macrovessel inflow contributions can be obtained by adjusting TIs. Signal changes in large vessel areas including the scalp were seen during finger opposition at a TI of 0.4 s; however, these were not observed at a longer TI of 1.4 s. To compare with commonly used BOLD and slice selective inversion recovery techniques, FAIR and BOLD images were acquired at the same time during unilateral finger opposition. Generally, activation sites determined by three techniques are consistent. However, activation of some areas can be detected only by FAIR, not by BOLD, suggesting that the oxygen consumption increase couples with the CBF change completely. Relative and absolute CBF changes in the contralateral motor cortex are 53 ± 17% SD (n = 9) and 27 ± 11 SD ml/100 g/min (n = 9), respectively. 相似文献
12.
Osteonecrosis of the jaws associated with use of risedronate: report of 2 new cases. 总被引:1,自引:0,他引:1
John K Brooks Allen J Gilson Arnold J Sindler Steven G Ashman Kevin G Schwartz Nikolaos G Nikitakis 《Oral surgery, oral medicine, oral pathology, oral radiology, and endodontics》2007,103(6):780-786
Use of various bisphosphonates has been associated with the development of osteonecrosis of the jaws (ONJ). At least 865 cases of ONJ attributed to these agents have been reported in the English-language literature. Approximately 96% of these published cases were seen with administration of the intravenous agents pamidronate and zoledronate, whereas only 26 cases have been associated with oral bisphosphonates, 25 of them with alendronate. Only a single case of ONJ associated with the oral bisphosphonate risedronate has been previously cited. We report 2 cases of ONJ attributed to risedronate administration. The patients developed osteonecrosis 15 and 24 months after treatment for osteopenia. A regimen of antibiotics and chlorhexidine mouthrinse resolved the osseous defect in the mandible caused by complete exfoliation of a lingual torus in 1 patient. The other patient required sequestrectomy, repeated courses of antibiotics, surgical debridement, and steroids to promote closure of an oroantral fistula and management of sinusitis after bone grafting and implant placement in the posterior maxilla. A demographic profile of reported oral bisphosphonate users affected by ONJ is also provided. With the millions of patients receiving various oral bisphosphonates for osteopenia and osteoporosis, health care practitioners should be aware of the potential for the onset of osteonecrosis and familiar with its management. 相似文献
13.
Richard C. Semelka Suvipapun Worawattanakul Nikolaos L. Kelekis Gesine John John T. Woosley Mark Graham William G. Cance 《Journal of magnetic resonance imaging : JMRI》1997,7(6):1040-1047
This study compares liver lesion detection, characterization, and effect on patient management between single-phase spiral CT and MRI using spoiled gradient echo (SGE), T2-weighted fat-suppressed spin echo, and serial post gadolinium SGE. All patients with suspected liver lesions who underwent spiral CT and MRI within a 1-month period between January 1993 and September 1996 were included in the study. Spiral CT and MRI were interpreted prospectively in a blinded fashion by separate individual experienced investigators, and lesion detection and characterization were determined. Confirmation was obtained by surgery (6 patients), biopsy (18 patients), imaging follow-up (36 patients), or combined reading of all imaging studies and clinical follow-up (29 patients). Effect on patient management was determined by combined chart review and interview of the patients' physicians and by retrospective clinical assessment performed by a surgical oncologist and medical oncologist separately. Eighty-nine patients were included in the study. Regarding true positive lesion detection, 295 and 519 lesions were detected on spiral CT and MR images, respectively, which was significantly different on a patient-by-patient basis (P < .001). More lesions were detected on MR than on spiral CT in 44 of 89 patients (49.4%), and 11 of these 44 patients had lesions shown on MRI in whom no lesions were apparent on CT images. No patients had true positive lesions shown on spiral CT that were not shown on MRI. Regarding lesion characterization, 129 and 466 lesions were characterized on spiral CT and MRI images, respectively, which was significantly different on a patient-by-patient basis (P < .001). More lesions were characterized on MR than CT images in 67 patients (75.3%). Regarding effect on patient management, chart review with physician interview demonstrated that findings on MRI provided information that altered patient management as compared with findings on spiral CT in 57 patients. Retrospective clinical evaluation by the surgical and medical oncologist showed that MRI was considered to have a greater effect on patient management than spiral CT in 58 and 55 patients, respectively. Comparing current MRI technique to single-phase spiral CT, MRI detected more lesions in 49.4% and characterized more lesions in 75.3% of patients investigated for focal liver disease. MRI had a greater effect on patient management in each of the three methods than singlephase spiral CT in more than 61% of patients. 相似文献
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15.
Prevalence and clinical significance of anticardiolipin antibodies in patients with type 1 autoimmune hepatitis 总被引:3,自引:0,他引:3
Liaskos C Rigopoulou E Zachou K Georgiadou S Gatselis N Papamihali R Dalekos GN 《Journal of autoimmunity》2005,24(3):251-260
There are few case reports on the association between autoimmune hepatitis (AIH) and anticardiolipin antibodies (anti-CLAbs) and/or antiphospholipid syndrome (APLS). We studied the anti-CLAbs prevalence in AIH and other hepatic diseases. We also investigated whether anti-CLAbs are co-factor dependent and which is their avidity since co-factor dependency or increased resistance is associated with APLS. Fifty-nine AIH patients, 228 HCV, 50 HBV, 123 with other non-viral and non-autoimmune liver disorders (nV-nALD) and 267 healthy people were investigated for anti-CLAbs and antibodies against beta-2-glycoprotein I (anti-beta2-GPI). Resistance of IgG anti-CLAbs was evaluated using 2 M urea. IgG anti-CLAbs detected in 39% of AIH, 19.7% of HCV (p=0.006), 14% of HBV (p=0.01), 8.1% of nV-nALD (p=0.000) and 1.1% of healthy (p=0.000). IgG anti-CLAbs were associated with the presence of cirrhosis and active AIH while their resistance to urea was high. Anti-beta2-GPI was detected in two AIH patients. We demonstrated a significantly higher prevalence of anti-CLAbs in patients with AIH compared to other diseases and healthy people. Anti-CLAbs were associated with AIH stage but no association was found with APLS clinical manifestations (thrombosis, pregnancy morbidity, thrombocytopenia). However, their avidity was comparable with that of APLS indicating the need for prospective studies in order to address whether anti-CLAbs in AIH may contribute to the progression of liver disease or APLS development. 相似文献
16.
17.
This article examines the empirical basis of using homework in psychotherapy and then offers a synthesis of the research literature with the preceding clinical articles. We provide a practitioner-friendly review of psychotherapy process and outcome research literature, concluding that there is now sufficient evidence to support the assertion that homework assignments enhance psychotherapy outcomes. It is also clear that homework compliance is a consistently significant predictor of treatment outcome. Limitations of existing studies and future research directions are outlined, and we suggest that more specific questions are required regarding the integration of homework into therapy process. Clinical recommendations and issues in homework administration described in preceding articles are also synthesized. The research evidence and contributors to this issue converge in recommending homework within the broad context of psychotherapy and using creative ways of administering homework that is customized to the client. 相似文献
18.
Ioannis S Elefsiniotis Aikaterini Petrocheilou Nikolaos Scarmeas Ioannis Ketikoglou Konstantinos D Pantazis Marina Toutouza Epameinondas V Tsianos 《Journal of clinical virology》2006,37(4):329-331
OBJECTIVES: To evaluate the alterations of serum procalcitonin (PCT) levels in patients with chronic hepatitis C during pegylated interferon-alpha (PEG-IFNa) plus ribavirin (RIB) treatment and to correlate them with clinical and virological outcomes. STUDY DESIGN: Fifty-two consecutive patients (29 males, age=41.2+/-14.7 years) with chronic HCV-related liver disease (six cirrhotics) were evaluated for PCT levels at baseline and during the treatment course (at week 12, 24, 48 and 72) with PEG-IFNa plus RIB. Sustained virological response (SVR) was confirmed by undetectable serum HCV-RNA at the end of treatment and again 6 months after completion of treatment. RESULTS: Two patients exhibited culture-proved bacterial infections during the treatment course. Thirty-six patients (69.2%) exhibit SVR and 16 (30.8%) were non-responders. Serum PCT levels remained within normal limits (0.1-0.5 ng/mL) in all treated patients throughout the follow-up period except those two who exhibited bacterial infections during the treatment course. Virological responders exhibited significant decline of serum PCT levels over time compared to non-responders (p<0.001), even when adjusted for multiple baseline parameters (p=0.037). CONCLUSION: Serum PCT levels decline in chronic hepatitis C patients during PEG-IFNa plus RIB treatment, especially in the sustained virological responder group, while they elevate only when bacterial infections complicate the treatment course. 相似文献
19.
Nikolaos Smyrnis Masato Taira James Ashe Apostolos P. Georgopoulos 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1992,92(1):139-151
Summary Two rhesus monkeys were trained to move a handle on a two-dimensional (2D) working surface in directions specified by a light at the plane. They first captured with the handle a light on the center of the plane and then moved the handle in the direction indicated by a peripheral light (cue signal). The signal to move (go signal) was given by turning off the center light. The following tasks were used: (a) In the non-delay task the peripheral light was turned on at the same time as the center light went off. (b) In the memorized delay task the peripheral light stayed on for 300 ms and the center light was turned off 450–750 ms later. Finally, (c) in the non-memorized delay task the peripheral light stayed on continuously whereas the center light went off 750–1050 ms after the peripheral light came on. Recordings in the arm area of the motor cortex (N= 171 cells) showed changes in single cell activity in all tasks. In both delay tasks, the neuronal population vector calculated every 20 ms after the onset of the peripheral light pointed in the direction of the upcoming movement, which was instructed by the cue light. Moreover, the strength of the population signal showed an initial peak shortly after the cue onset in both the memorized and non-memorized delay tasks but it maintained a higher level during the memorized delay period, as compared to the non-memorized task. These results indicate that the motor cortex is involved in encoding and holding in memory directional information concerning a visually cued arm movement and that these processes can be visualized using neuronal population vector analysis. 相似文献
20.
Ioana Maris Sabine Dölle-Bierke Jean-Marie Renaudin Lars Lange Alice Koehli Thomas Spindler Jonathan Hourihane Kathrin Scherer Katja Nemat C. Kemen Irena Neustädter Christian Vogelberg Thomas Reese Ismail Yildiz Zsolt Szepfalusi Hagen Ott Helen Straube Nikolaos G. Papadopoulos Susanne Hämmerling Ute Staden Michael Polz Tihomir Mustakov Ewa Cichocka-Jarosz Renata Cocco Alessandro Giovanni Fiocchi Montserrat Fernandez-Rivas Margitta Worm Network for Online Registration of Anaphylaxis 《Allergy》2021,76(5):1517-1527