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排序方式: 共有985条查询结果,搜索用时 210 毫秒
71.
Study of movement disorders and brain iron by MR 总被引:2,自引:0,他引:2
J N Rutledge S K Hilal A J Silver R Defendini S Fahn 《AJR. American journal of roentgenology》1987,149(2):365-379
Heavily T2-weighted high-field MR images provide a unique opportunity for the evaluation of the extrapyramidal motor system. The images are affected by the presence of small amounts of naturally occurring paramagnetic substances--principally iron--that delineate the neostriatum (caudate and putamen), globus pallidus, red nucleus, substantia nigra, and dentate nucleus, primarily by a decrease in signal secondary to the T2* effect. Movement disorders are associated with either increased or decreased signal or both in these structures, depending on the pathologic process. In the initial evaluation of 113 patients with a variety of movement disorders, good correlation of imaging abnormalities can be made with a simplified schema of the extrapyramidal pathways and a system of classification of abnormal movements, parkinsonism/tremor, dystonia, chorea, myoclonus, and hemiballismus. Parkinsonisms are characterized by abnormalities of the cortico-ponto-cerebello-dentato-rubro-thalamo-cortico-spinal tract or the nigrostriatal tract. Dystonias are characterized by abnormalities of the neostriatum predominantly affecting the putamen. Choreas are also characterized by abnormalities of the neostriatum but predominantly affecting the caudate nucleus. Hemiballismus is characterized by lesions affecting the subthalamic nucleus or associated pathway. 相似文献
72.
A magnetic resonance imaging pulse sequence featuring a short echo time of 3.6 ms is described and used clinically for in vivo imaging of sodium-23 in the human head. In living tissues, sodium exhibits at least two transverse relaxation constants, namely, (a) a short component T2s = 0.7-3.0 ms and (b) a long component T2e = 16-30 ms. Since our first in vivo imaging of sodium, an echo time of 10-15 ms has been used by us and by other investigators. This echo time is adequate for the observation of the long T2 component of sodium. However, a substantial fraction of the sodium, namely, the short T2 component, representing about 40%, has remained undetected by the imaging method with this echo time and is now observable by the new pulse sequence. The proposed method is a hybrid technique combining both projection reconstruction and Fourier encoding schemes. The projection reconstruction is used for the xy plane imaging while the Fourier encoding is used for slice separation. Sodium MR images of the human head produced with a short and a long TE are presented and analyzed. There is an increase in the MR signal and improved visibility of intraparenchymal sodium with the new scheme of short TE. 相似文献
73.
BACKGROUND/AIMS: In our study, the effects of somatostatin (SS) and ursodeoxycholic acid (UDCA) on ischemic liver injury were studied in (obstructive) jaundice-rat model. METHODOLOGY: For this purpose, jaundice was produced in the first four groups by binding of their choleducts. We performed just laparotomy to the other four groups of animals. To groups 1 and 5, SS was given 15 mcg/kg/day intraperitoneally, and to groups 2 and 6, UDCA was given 20 mg/kg/day enterally. No drugs were given to any other group. At the end of one week, a procedure with ischemia of the liver for 60 minutes followed by reperfusion for 2 hours, was performed to each rat except for groups 4 and 8. Following this procedure, they were sacrificed. The blood samples were taken to measure SGOT, SGPT, ALP, LDH, total and direct bilirubin levels, while liver biopsies were taken for histopathological evaluation. RESULTS: Under normothermic conditions, following 60-minute liver ischemia period, no irreversible histopathological changes were detected. However, increases in liver necrosis parameters were noted biochemically. SS and UDCA were thought to be effective in preventing the injury by decreasing the liver enzymes levels to a significant degree. The damage of the hepatic ischemic injury was found to be more meaningful and prominent in liver with jaundice. CONCLUSIONS: In this study, it was noted that SS and UDCA decrease the effects of cholestatic hepatic injury especially and improve the condition. 相似文献
74.
Sen N Ermis H Karatasli M Habesoglu MA Eyuboglu FO 《Respiration; international review of thoracic diseases》2007,74(6):703-705
We describe an unusual case of a patient with eosinophilic pleural effusion (EPE) associated with long-term propylthiouracil (PTU) administration. A 43-year-old woman was admitted to our hospital after complaining of chest pain. She had had Graves' disease, which had been treated with PTU for 11 years. Right-sided pleural effusion was detected and the result of thoracentesis confirmed an EPE. The patient's detailed medical evaluation failed to reveal any other cause of EPE. PTU was terminated since it was thought to be the cause. Despite withdrawal of the medication, however, the pleural effusion persisted for 6 weeks, and steroid therapy was planned for 15 days in decreasing dosages. During the control visit 10 days after the initiation of steroid therapy, no pleural effusion was observed, and the steroid was discontinued. Rechallenge with PTU produced recurrent pleural effusion. Therapy with PTU was again terminated, and treatment with methimazole and a brief course of low-dose corticosteroids were begun. Chest radiography revealed disappearance of the effusion within 10 days and it did not recur during a 1-year follow-up. To our knowledge, there is only 1 other case in the English-language literature describing EPE caused by PTU. Our report is of particular importance because it describes the development of that disorder in the 11th year of PTU treatment. It also shows that steroid therapy can be effective in treating drug-induced EPE. 相似文献
75.
76.
Sanjay Jaju Samir Al-Adawi Hilal Al-Kharusi Magdi Morsi Asya Al-Riyami 《Child and adolescent psychiatry and mental health》2009,3(1):29-11
Background
There is a dearth of studies exploring the magnitude of mental disorders amongst adolescents and youths in the Arab world. To our knowledge, this phase 2 survey in Oman is the first nationally representative school-based study to determine the prevalence of DSM-IV mental disorders (lifetime and over the preceding 12 months), their age-of-onset distributions and determine their severity over the past 12 months using the World Mental Health-Composite International Diagnostic Interview, the WMH-CIDI, used for international comparison. 相似文献77.
Asya A Al Riyami Samir H Al Adawi Hilal A Al Kharusi Magdi M Morsi Sanjay S Jaju 《International journal of mental health systems》2009,3(1):22-11
Background
Recent corpus of research suggests that psychiatric disorders amongst adolescents and youths are an emerging global challenge, but there is paucity of studies exploring health services utilization by this age group in Arab region. 相似文献78.
Obesity has reached epidemic proportions in many countries and is an established risk factor in many chronic illnesses, but
its role in acute illness is less clear. Pancreatologists have long recognized obesity as a risk factor for a poor outcome
in severe acute pancreatitis. There are now several studies that have identified obesity as a primary risk factor for developing
local complications (abscess, pseudocyst, necrosis), organ failure, and death. Indeed, meta-analysis of these studies gives
a relative risk of 4.3 for local complications, 2.0 for systemic complications, and 2.1 for death. This has led to proposed
modifications of acute pancreatitis scoring systems to include obesity as an independent primary predictive factor of severe
disease. Obesity is associated with a low-grade inflammatory state, which may predispose obese patients to such complications.
Furthermore, visceral obesity and visceral adipose tissue may be particularly important in underlying the pathophysiology
of these observations. 相似文献
79.
Davis JM Maradit Kremers H Crowson CS Nicola PJ Ballman KV Therneau TM Roger VL Gabriel SE 《Arthritis and rheumatism》2007,56(3):820-830
OBJECTIVE: To determine the relationship between glucocorticoid exposure and cardiovascular (CV) events in patients with rheumatoid arthritis (RA). METHODS: A total of 603 adult residents of Rochester, Minnesota with incident RA between 1955 and 1995 were followed up through their medical records for a median of 13 years (total of 9,066 person-years). Glucocorticoid exposure was defined 3 ways: tertiles of cumulative exposure; recent use (< or =3 months) versus past use (>3 months); and average daily dosage (< or =7.5 mg/day or >7.5 mg/day). CV events, including myocardial infarction, heart failure, and death from CV causes, were defined according to validated criteria. Cox regression models were adjusted for demographic features, CV risk factors, and RA characteristics. RESULTS: Rheumatoid factor (RF)-negative patients with exposure to glucocorticoids were not at increased risk of CV events, irrespective of the glucocorticoid dosage or timing of use, as compared with the reference group of RF-negative patients who had never been exposed to glucocorticoids. In contrast, RF-positive patients were at increased risk of CV events, particularly with higher cumulative exposure, higher average daily dosage, and recent use of glucocorticoids. RF-positive patients with high cumulative exposure to glucocorticoids had a 3-fold increased risk of CV events (hazard ratio 3.06 [95% confidence interval 1.81-5.18]), whereas RF-negative patients with high cumulative exposure were not at increased risk (hazard ratio 0.85 [95% confidence interval 0.39-1.87]). CONCLUSION: RF-positive but not RF-negative patients were at increased risk of CV events following exposure to glucocorticoids. These findings suggest that glucocorticoids interact with RF status to modulate the occurrence of CV events in patients with RA. The mechanisms underlying this interaction are unknown and should be the subject of further research. 相似文献
80.