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91.
A significant recent advance that has occurred world over in the continuously evolving field of Magnetic Resonance Imaging (MRI) practice is the introduction of Cardiac applications. Cardiac MRI has moved to the centre stage of clinical management strategy by non-invasively imaging the structure as well as function of the heart. It has a wide range of specific applications such as delineation of morphological anatomy, quantification of flow and pressure across cardiac valve dysfunction, evaluation of myocardial function, assessment of infarcts, mapping coronary arteries and so on. Evaluation of congenital heart disease (CHD) is an important application of Cardiac MRI since the morphological details of chambers, septum, defects and anomalous connections are depicted accurately. Besides, flow information across valves, chambers, outflow tracts and shunts are also provided. This article describes our experience in the use of cardiac MRI in congenital heart disease.Key Words: Cardiac MRI, Congenital heart disease, Cyanotic and Acyanotic heart disease 相似文献
92.
BACKGROUND: Low bone mineral density (BMD) is common in dialysis patients. Low BMD predicts the fracture risk in the general population. Bisphosphonate therapy improves BMD and lowers the fracture risk in many populations, but has not been tested in dialysis patients because of concerns about toxicity. In this investigation, the effect of a short course of alendronate on BMD in haemodialysis (HD) patients is evaluated. METHODS: Thirty-one healthy HD patients were randomized to placebo versus 40 mg alendronate, taken once a week for 6 weeks. Hip and lumbar spine BMD were measured by dual energy X-ray absorptiometry at baseline and at 6 months. Osteocalcin, parathyroid hormone, calcium, phosphorous and alkaline phosphatase levels were assayed at baseline and at 1, 3 and 6 months. RESULTS: The BMD and T-scores in specific regions of the hip were stable in the treatment group and decreased in the placebo group (P=0.05). The lumbar spine density increased minimally in both groups. In the treatment group, osteocalcin levels declined significantly at 1 month (P<0.05) and remained low. The main side-effect in the alendronate group was occurrence of gastroesophageal reflux symptoms in three subjects. CONCLUSIONS: Low-dose alendronate, administered for a limited duration, appears to be well tolerated in dialysis patients. The BMD and T-scores declined at certain hip regions in the placebo group over 6 months, while remaining stable in the treatment group, suggesting a bone-preserving effect of alendronate. Further studies of longer duration, and including examination of bone histology, are needed to assess whether bisphosphonates can be used to preserve BMD in dialysis patients. 相似文献
93.
A molecular fingerprint for medulloblastoma 总被引:12,自引:0,他引:12
Lee Y Miller HL Jensen P Hernan R Connelly M Wetmore C Zindy F Roussel MF Curran T Gilbertson RJ McKinnon PJ 《Cancer research》2003,63(17):5428-5437
Medulloblastoma is the most common malignant pediatric brain tumor. In mice, Ptc1 haploinsufficiency and disruption of DNA repair (DNA ligase IV inactivation) or cell cycle regulation (Kip1, Ink4d, or Ink4c inactivation), in conjunction with p53 dysfunction, predispose to medulloblastoma. To identify genes important for this tumor, we evaluated gene expression profiles in medulloblastomas from these mice. Unexpectedly, medulloblastoma expression profiles were very similar among tumors and also to those of developing cerebellum. However, 21 genes were specifically up-regulated in medulloblastoma, including sFrp1, Ptc2, and Math1, members of signaling pathways that regulate cerebellar development. Coordinated deregulation of these same genes also occurred in a large subset of human medulloblastomas. These data identify a group of genes that is central to medulloblastoma tumorigenesis. 相似文献
94.
Singer and Blom have recently reported a new surgical method for speech rehabilitation of the alaryngeal patient. The method consists of a tracheoesophageal puncture (TEP) followed 2 to 3 days later by insertion of a silicone “duckbill” prosthesis which acts as a one-way valve allowing pulmonary air to enter and vibrate the esophagus but preventing aspiration. Along with more rapid acquisition of speech, the advantage of tracheoesophageal speech over esophageal speech is the greater volume of air flow through the vibrating segment of the esophagus, which allows smoother and more prolonged speech. Thirteen of our 18 patients (72%) who have undergone TEP are currently using tracheoesophageal speech. The complications associated with this procedure include the TEP tract closing, tracheal mucositis, stenosis of the tracheostoma, aspiration of the prosthesis, esophageal tear, and aspiration from the esophagus. Although we have encountered several problems, we enthusiastically endorse this procedure since it provides oral communication which is comparable to, and in many cases better than, that of the majority of esophageal speakers. 相似文献
95.
96.
Purpose.?To explore disability in women with fibromyalgia with a focus on their work situation.Method.?Review of literature on work status of women with fibromyalgia.Results.?Major differences exist between studies in reported disability and in the percentages of women working. Limitations caused by pain, fatigue, decreased muscle strength, and endurance influence work capacity. However, 34?–?77% of the women work. Individual adjustments in the work situation are reported. When the women find a level that matches their ability, they continue to work and find satisfaction in their work role. Many factors besides degree of impairment or disability influence whether clients with longstanding pain can remain in their work role or return to work after sickness leave.Conclusion.?The total life situation, other commitments, type of work tasks, the ability to influence the work situation, and the physical and psychosocial work environment are important factors in determining whether a person can remain in a work role. More knowledge is needed about how to adjust work conditions for people with partial work ability to the benefit of society and the individual. 相似文献
97.
Pineal germinoma: MR imaging 总被引:6,自引:0,他引:6
Magnetic resonance (MR) imaging characteristics of pineal germinomas are described in seven patients imaged with MR and computed tomography (CT). In patients with symptoms of an enlarging process in the quadrigeminal plate cistern, MR imaging was as sensitive as CT scanning in detecting the mass. MR imaging did not detect a normal-sized, calcified neoplastic gland. Germinoma, germinoma with embryonal cell carcinoma elements, and pineoblastoma demonstrated different MR signal characteristics. Although direct coronal and sagittal MR images were useful in defining the relationship of the tumor to the posterior third ventricle, Sylvian aqueduct, and vein of Galen, the ease, rapidity, and sensitivity of CT scanning suggest that CT should remain the modality of choice for initial evaluation and screening of the pineal region, especially in the younger pediatric population, in whom detection of calcification may provide the only clue of an abnormality. 相似文献
98.
Detection and quantification of chronic cerebrovascular disease: comparison of MR imaging, SPECT, and CT 总被引:1,自引:0,他引:1
Seiderer M; Krappel W; Moser E; Hahn D; Schmiedek P; Buell U; Kirsch CM; Lissner J 《Radiology》1989,170(2):545-548
Twenty patients with angiographically proved occlusion of the internal carotid artery (ICA) (19 unilateral, one bilateral) were studied with magnetic resonance (MR) imaging, iodine-123 iodoamphetamine (IMP) single photon emission computed tomography (SPECT), xenon-133 SPECT, and computed tomography (CT). All patients had a history of stroke or prolonged reversible ischemic neurologic deficit for more than 4 weeks. By regions of interest, T1, T2, regional cerebral blood flow (rCBF), and the number and size of the lesions were determined. The data were expressed as interhemispheric ratios (diseased/nondiseased). The highest ratios obtained were for MR imaging (T1, 2.60 +/- 0.42; T2, 1.61 +/- 0.22 [mean +/- standard deviation]) followed by Xe-133 SPECT (0.58 +/- 0.13) and IMP SPECT (0.56 +/- 0.13). Correlation coefficients for MR imaging (1/T1, 1/T2) and IMP SPECT were below .21. The lesion size was greatest on IMP SPECT images, intermediate on MR images, and least on CT scans. However, MR imaging was superior in detection of pathologic areas (detection rates: MR, 100%; IMP SPECT, 91%; CT, 79%). Relaxation times do not correlate with rCBF. 相似文献
99.
100.
Gina Peacock Sarah Parnapy Shelby Raynor Stewart Wetmore 《Journal of the American Pharmacists Association》2010,50(1):84-86
ObjectiveTo compare the accuracy and precision of a manufacturer-supplied dropper versus a pharmacy-supplied syringe when measured by a trained student pharmacist and to evaluate patients' ability to accurately measure a prescribed amount of medication with these devices before and after counseling on their use.MethodsThis was a two-phased study with a pretest/posttest design of 125 community pharmacy patrons of Virginia community pharmacies. Deliverable volume was measured by a student pharmacist for nystatin suspension and digoxin elixir using the manufactured-supplied device. Patients at pharmacies were asked to complete a short survey, then asked to measure a specified dose of nystatin suspension and digoxin elixir (using the manufacturer-supplied administration device). The patients repeated this a second time after a student provided education on how to properly use each administration device. The main outcomes measure was whether education on an administration device would provide more measurement accuracy using medications with different physical properties.ResultsFor nystatin, 88% and 85.6% of patients measured with an error of greater than or equal to 20% before and after counseling, respectively. For digoxin, the totals were 24.8% before counseling and 4% after. A statistically significant (P < 0.05) difference was observed in the percent measurement error before and after counseling for nystatin and digoxin both for patients who had been educated before the study and for those who had not been counseled.ConclusionIn general, the accuracy of medication dosage devices seems to be most affected by viscosity of the liquid being measured. With education on proper use, the oral syringe provides a statistically and clinically significant improvement in dosing accuracy for viscous medications compared with the manufacturer-supplied dropper. Pharmacists must review with patients the proper way to use a manufacturer- or pharmacy-supplied oral delivery device for appropriate dosing measurements. 相似文献