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41.
Imaging of the liver is performed most often to detect and characterize focal liver lesions. MR imaging has been the method of choice to assess focal liver lesions accurately. Nonspecific intravenous contrast agents have been used for routine abdominal MR imaging protocols including liver imaging. Over the last 10 to 15 years new contrast agents have been developed that combine the excellent contrast resolution of MR imaging with improved tissue specificity. This article reviews various contrast agents that are in clinical use for liver MR imaging and discusses their potential clinical role. 相似文献
42.
Poland syndrome has been sporadically associated with hematological conditions, primarily acute leukemias. The authors report a child with this syndrome coexisting with temporary hematological dysplasia due to iron deficiency. Further hematological evaluation failed to demonstrate malignancy. Because of its premalignant nature, in patients with Poland syndrome, hematological dysplastic features should be an indication for further investigation. However, in addition to the well-known hematological malignancies, treatable causes may be responsible. 相似文献
43.
Re-expansion pulmonary edema (REPE) is an uncommon complication following re-expansion of the lung as treatment of conditions such as hemopneumothorax, large pleural effusion, and after lobectomy, pneumothorax, or even during single-lung ventilation. The majority of REPE complications are associated with treatment of spontaneous pneumothorax. The etiology of REPE remains speculative, although it is thought to be caused by increased pulmonary capillary permeability. Risk factors, including young age, a large pneumothorax, and long duration of collapse, may help predict the patients that might encounter this complication. 相似文献
44.
In the present study, we have examined whether increased N-ANP (N-terminal pro-ANP) levels before and after surgery in patients with ASD (atrial septal defect) along with echocardiographic findings provide a better insight into the pathophysiology and increased morbidity and mortality following corrective surgery. Eighteen adult ASD patients (> 20 years of age; six male and 12 female) with shunts (Qp/Qs > or = 2, where Qp/Qs is the pulmonary blood flow/systemic blood flow) had complete echocardiographic, clinical and laboratory parameters evaluated before and 6 months after surgery. Eight age- and sex-matched individuals (three male and five female) were enrolled as a control group. Blood samples for N-ANP analysis were obtained in both groups. N-ANP levels in the peripheral blood sample from ASD patients before surgery were significantly higher than those in the control group. In patients with ASD, mean N-ANP levels obtained from the pulmonary artery were significantly higher than that obtained from the peripheral vein. RA (right atrial) area, adjusted for body surface area, and RA long-axis and short-axis measurements were significantly higher in the patient group than the control group. N-ANP was correlated significantly with these parameters. Following corrective surgery, N-ANP values and RA area, RA long-axis and short-axis normalization decreased significantly and were accompanied by a decrease in systolic mean pulmonary artery pressure. N-ANP levels were normalized following septal closure in most patients, except in those with atrial fibrillation attacks following corrective surgery. In conclusion, we have shown correlations among variables indicating changes in the architecture of the right atrium along with temporal changes in ANP providing insights into the pathophysiology of post-operative atrial arrhythmias. 相似文献
45.
Karslioglu I Ertekin MV Koçer I Taysi S Sezen O Gepdiremen A Balci E 《European journal of ophthalmology》2004,14(6):478-485
PURPOSE: To determine the antioxidant role of vitamin E (VE) (10 mg/kg/day) against radiation-induced cataract in lens after total-cranium irradiation of rats with a single dose of 5 Gy. METHODS: Sprague-Dawley rats were divided into three groups. Group 1 did not receive VE or irradiation but received both 0.1 ml physiologic saline intraperitoneally and sham irradiation (control group). Group 2 received to total cranium 5 Gy of gamma irradiation as a single dose (RT group) plus 0.1 ml physiologic saline intraperitoneally. Group 3 received irradiation to total cranium plus 10 mg/kg/day VE (RT+VE group). The rats were irradiated using a cobalt-60 teletherapy unit. Chylack's cataract classification (1) was used in this study. At the end of 10 days, the rats were killed and their eyes were enucleated to measure the antioxidant enzymes (the activity of superoxide dismutase [SOD], glutathione peroxidase [GSH-Px]) and lipid peroxidation level (malondialdehyde [MDA]). RESULTS: While grade 1 cataract development was detectable in seven rats in the RT group, it was detectable only in two rats in the RT+VE group, whereas none of the rats in the control group exhibited any biomicroscopic change in their lenses. MDA level and GSH-Px activity in the rat lens in the RT group was significantly higher than in the control group. SOD activity in the RT group was lower than in the control group. The activity of SOD and GSH-Px enzymes was higher in the RT+VE group, but MDA level was lower in the RT+VE group when compared with the RT group. CONCLUSIONS: Vitamin E has a protective effect on radiation-induced cataract by decreasing oxidative stress. 相似文献
46.
Prolonged hyperglycemia in the early subacute period after cerebral infarction: effects on short term prognosis 总被引:4,自引:0,他引:4
Dora B Mihçi E Eser A Ozdemir C Cakir M Balci MK Balkan S 《Acta neurologica Belgica》2004,104(2):64-67
Although the adverse effect of admission hyperglycemia in cerebral infarction on prognosis is well known, studies generally have not questioned the effect of hyperglycemia in the early subacute period on prognosis after a stroke. Forty-six patients with acute ischemic stroke were seperated into 3 groups: Group 1) Known diabetes or admission blood glucose (ABG) > or = 140 mg/dl and HbA1c > or = 8,0%); Group 2) ABG > or = 140 mg/dl and HbA1c < 8,0%; and Group 3) ABG < 140 mg/dl and HbA1c < 8,0%. Blood glucose was followed-up 4 times a day for 10 days after the stroke and the mean of these measurements was calculated as the mean of glycemic regulation (MGR). Neurological evaluation was done at presentation and on day 10 and 30 with the National Institute of Health (NIH) scale. Oedema, lesion size and presence of hemorrhagic transformation were evaluated using CT. The MGR was significantly higher in group 1 compared to the other two groups (p < 0,001 and p < 0,01) and in group 2 compared to group 3 (p < 0,001). Patients with clinical worsening had a significantly higher MGR (p < 0,05). Patients with marked cerebral edema had a significantly higher MGR (p < 0,01) compared to patients with lesser edema. No correlation was found between MGR and lesion size or hemorrhagic transformation. Our results show that hyperglycemia in the early subacute period after cerebral infarction is associated with more pronounced cerebral edema and has an adverse effect on short term prognosis. We suggest that studies investigating the effect of insulin infusion on stroke prognosis should also consider infusions for a longer period than 24 hours. 相似文献
47.
BACKGROUND: Testing of tendon (T) reflex is the basic method used in the diagnostic procedure of clinical neurology. Measurement of T reflexes precisely can be a valuable adjunct to clinical examination. Quantification of T reflexes may provide more accurate results. AIMS: To analyze the effect of elbow position on biceps T reflex. SETTINGS AND DESIGN: A self-controlled clinical trial of biceps T reflex testing at the Electrophysiology Unit of the Department of Physical Medicine and Rehabilitation. METHODS AND MATERIALS: Biceps T reflex was obtained utilizing a hand-held electronic reflex hammer in 50 extremities of 25 healthy volunteers and the effect of elbow position (at 90 degrees , 120 degrees and 150 degrees ) on reflex response was evaluated. STATISTICAL ANALYSIS: Repeated-measures analysis of variance by the General Linear Model and Pearson correlation test procedures. RESULTS: Onset latency was significantly shorter at 120 degrees of elbow position. The maximum amplitude value of biceps T reflex was obtained at 90 degrees of elbow position. Onset latency of the reflex correlated significantly with the height and arm length but not with age. CONCLUSIONS: The electrophysiological measurement of T reflexes is an easy and useful method in the quantification of reflexes, supplying more objective data. However, when performing T reflex studies, the position of the extremity should be taken into consideration to achieve more reliable results. 相似文献
48.
Ertekin MV Tekin SB Erdogan F Karslioglu I Gepdiremen A Sezen O Balci E Gündogdu C 《Journal of radiation research》2004,45(4):543-548
There is currently substantial clinical interest in zinc (Zn) as a protective agent against radiation-related normal tissue injury. To further assess this drug's potential, the effect of Zn was studied in rats using a radiation-induced skin injury model. Sprague-Dawley rats were divided into four groups. Group 1 received neither Zn nor irradiation (control group). Group 2 received 30 Gy of gamma irradiation as a single dose to the right hind legs of the rats (RT Group). Groups 3 and 4 received the same irradiation plus 5 mg/kg/day Zn (RT+5 Zn group) or 10 mg/kg/day Zn orally (RT+10 Zn group), respectively. The rats were irradiated using a cobalt-60 teletherapy unit. Acute skin reactions were assessed every three days by two independent radiation oncology experts. At the endpoint of the study, light-microscopic findings were assessed by two independent expert pathology physicians. Clinically and histopathologically, irradiation increased dermatitis when compared with the control group (p < 0.05). The severity of radiodermatitis of the rats in the RT+5 Zn and RT+10 Zn groups was significantly lower than in the RT group (p < 0.05); radiodermatitis was seen earlier in the RT group than in the other groups (p < 0.05). Zn was found to be efficacious in preventing epidermal atrophy, dermal degeneration such as edema and collagen fiber loss, and hair follicle atrophy. The most protection for radiation dermatitis was observed in the RT+10 Zn group. It would be worthwhile studying the effects of zinc sulphate supplements in radiation-treated cancer patients, in the hope of reducing radiation-induced toxicity. 相似文献
49.
Hospital records of 1160 children 相似文献
50.
Cervico-oculo-acoustic (COA) or Wildervanck syndrome is characterized by the triad of Klippel-Feil anomaly, bilateral abducens palsy with retracted bulbs (Duane 'syndrome') and hearing loss. The clinical findings of this syndrome have been well documented. A few case reports with MRI findings have appeared in the literature showing brainstem and cerebellar hypoplasia and vertebral segmentation anomalies. Our case is unique in that diastematomyelia of the lower medulla and cervical cord was accompanied by vermian hypoplasia, tonsillar herniation and resulting triventricular hydrocephalus in a child with Wildervanck syndrome. This case is presented with MR images. Children with Wildervanck syndrome should be investigated for craniospinal abnormalities with MR imaging. 相似文献