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991.
以冠状动脉造影作对照,应用运动负荷201Tl心肌断层显像检查67例冠心病患者和34例健康人。结果显示,核素显像的灵敏度为91%,特异性为79%,检测左冠状动脉前降支(LAD)、右冠状动脉(RCA)和左冠状动脉回旋支(LCX)的灵敏度和特异性分别为89%和80%、89%和98%及81%和97%;单支、双支和3支冠脉受累时显像的灵敏度分别为85%、92%和100%。结果提示,心肌断层显像方法对冠心病患者心肌受累的部位、范围和程度、受累冠脉的判定提供了一种简便无创、灵敏有效的检测手段,具有较大的临床价值。 相似文献
992.
T. J. Vogl S. Steiner B. Schnell A. Gerbes C. McMahon C. Wilimzig J. Lissner 《European radiology》1992,2(4):310-316
Twenty-nine patients with diffuse liver disease were examined by ultrasound, CT and MRI. MRI was performed using T1- and T2-weighted spin-echo sequences as well as fast gradient-echo-sequences. The paramagnetic contrast agent Gd-DTPA was applied intravenously (0.1 mmol/kg). in patients with hepatitis, MRI could be used in guiding liver biopsies as inflammatory changes were clearly delineated. CT and ultrasound were superior to MRI in the detection of focal or diffuse fatty degeneration. On the other hand MRI was more helpful in differentiating fatty changes and neoplasm. In liver cirrhosis, fibrotic changes were most clearly demonstrated by MRI. In patients suffering from hemochromatosis MRI offers advantages over CT and ultrasound in the diagnosis and follow up due to the paramagnetic properties of iron, resulting in a reduction in signal intensity. In patients with Wilson's disease a characteristic pattern of parenchymal changes was seen. Administration of Gd- DTPA contributes additional information about perfusion conditions in the liver parenchyma, however this information was not of diagnostic relevance in the cases we studied.
Correspondence to: T.J. Vogl 相似文献
993.
Significance of haemorrhagic lacunes on MRI in patients with hypertensive cerebrovascular disease and intracerebral haemorrhage 总被引:4,自引:1,他引:3
Our purpose was to determine the frequency and signifcance of haemorrhagic lacunes (HL) on MRI in patients with a history of, or at risk for intracerebral haemorrhage. We examined 72 patients with old spontaneous intracerebral haemorrhage (ICH) using T1-and T2-weighted spin-echo sequences. MRI studies of 137 consecutive patients with cerebrovascular disease but no known ICH were also reviewed. Both groups showed about the same degree of age-related white matter change and nonhaemorrhagic lacunar infarcts, whereas the ICH group had a higher frequency of HL (12/72 patients) than the non-ICH group (6/131 patients,p<0.01). These results correlate well with reported pathological findings. We conclude that haemorrhagic lacunes found on MRI studies of patients with cerebrovascular disease may suggest a higher risk of intracerebral haemorrhage. 相似文献
994.
Manipulation of gamma-aminobutyrate (GABA) system has been little studied in Parkinson's disease, despite the fact that GABA subserves a large part of the basal ganglia, including the outflow tracts. To test whether antagonism of GABA could improve features of PD, we administered open label intravenous flumazenil to eight practically defined off patients and assessed UPDRS scores, bilateral 1-minute hand-tapping speed, and timed gait tests. Patients demonstrated significantly greater tapping speed, which peaked 40 minutes after injection (P < 0.05). Total motor Unified Parkinson's Disease Rating Scale scores modestly improved (P < 0.05). There were no adverse events. Mechanisms by which flumazenil could improve PD are discussed. 相似文献
995.
J. D. Schaafsma Y. Balash T. Gurevich A. L. Bartels J. M. Hausdorff N. Giladi 《European journal of neurology》2003,10(4):391-398
To assess the effect of levodopa on distinct freezing of gait (FOG) subtypes in patients with 'off' FOG. Nineteen patients (12 men, mean age 62.0 +/- 8.4 years) with Parkinson's disease and clinically significant FOG during 'off' states were videotaped whilst walking 130 m during 'off' and 'on' states. Three independent observers characterized the type, duration, and clinical manifestations and quantified FOG by analyzing the videotapes. Their combined mean scores were used for statistical analysis. The intra-class correlation coefficient assessed inter-observer reliability. Wilcoxon and Friedman tests evaluated differences in mean frequencies of FOG characteristics. During 'off' states, FOG was elicited by turns (63%), starts (23%), walking through narrow spaces (12%) and reaching destinations (9%). These respective values were only 14, 4, 2 and 1% during 'on' states (P < 0.011). Moving forward with very small steps and leg trembling in place were the most common manifestations of FOG; total akinesia was rare. Most FOG episodes took <10 s and tended to be shorter during 'on' states. Levodopa significantly decreased FOG frequency (P < 0.0001) and the number of episodes with akinesia (P < 0.001). Distinction amongst FOG subtypes enables evaluation of distinctive therapeutic response. Levodopa helps in reducing the frequency and duration of 'off'-related FOG. 相似文献
996.
Dopamine transporter density is decreased in parkinsonian patients with a history of manganese exposure: What does it mean? 总被引:2,自引:0,他引:2
Y Kim J-M Kim J-W Kim C-I Yoo C R Lee J H Lee H K Kim S O Yang H K Chung D S Lee B Jeon 《Movement disorders》2002,17(3):568-575
Manganese (Mn) exposure can cause parkinsonism. Pathological changes occur mostly in the pallidum and striatum. Two patients with a long history of occupational Mn exposure presented with Mn-induced parkinsonism. In one patient, magnetic resonance imaging (MRI) showed findings consistent with Mn exposure, and Mn concentration was increased in the blood and urine. However, this patient's clinical features were typical of idiopathic Parkinson disease (PD). Previous pathological and positron emission tomography studies indicate that striatal dopamine transporter density is normal in Mn-induced parkinsonism, whereas it is decreased in PD. Therefore, we performed [(123)I]-(1r)-2 beta-carboxymethoxy-3beta-(4-iodophenyl)tropane ([(123)I]-beta-CIT) single-photon emission computed tomography. Severe reduction of striatal beta-CIT binding was indicated, which is consistent with PD. We propose three interpretations: (1) the patients have PD, and Mn exposure is incidental; (2) Mn induces selective degeneration of presynaptic dopaminergic nerve terminals, thereby causing parkinsonism; or (3) Mn exposure acts as a risk of PD in these patients. Our results and careful review of previous studies indicate that the axiom that Mn causes parkinsonism by pallidal lesion may be over-simplified; Mn exposure and parkinsonism may be more complex than previously thought. Further studies are required to elucidate the relationship between Mn and various forms of parkinsonism. 相似文献
997.
We assessed the feasibility and psychometric properties of two commonly used health status questionnaires in Parkinson's disease (PD): the generic Nottingham Health Profile (NHP) and the disease-specific 39-item Parkinson's disease Questionnaire (PDQ-39), from a cross-sectional postal survey of PD patients (N = 81), using traditional and Rasch measurement methodologies. Overall response rate was 88%. Both questionnaires were found feasible, although the NHP performed less well. The PDQ-39 had fewer floor effects and was better able to separate respondents into distinct groups than the NHP, whereas the latter exhibited less ambiguous dimensionality and better targeting of respondents with non-extreme scores. Reliability and validity indices were similar, and potential differential item functioning by age and gender groups was found for both questionnaires. PDQ-39 response alternatives indicated ambiguity. With few exceptions, questionnaire scales were unable to meet recommended standards fully. While preliminary, this study illustrates the need for thorough evaluation of outcome measures and has implications beyond the questionnaires used here. Although promising, both questionnaires warrant further developmental work and stronger support of measurement validity before they could be considered fully suitable for valid use in PD, in particular in earlier stages of the disease. 相似文献
998.
Summary
The compartment syndrome (cs) is characterized by an increased tissue pressure in a limited space. Pathophysiologically, it
is a multifactorial disease that is potentially induced by an initial trauma and develops according to the existence of cofactors.
Cofactors are, for instance, the circulation of the patient and the initial treatment of the impending cs. In particular,
the microcirculation is altered with endothelial destruction, development of a capillary leak, protein loss from intravasal
space and the development of an interstitial and intracellular third space. An impaired drainage of the lymphatic and venous
system causes a venous infarction. An arterial infarction results if the tissue pressure exceeds the arteriolar pressure.
An accompanying ischemia reperfusion mechanism increases the trauma load. In disadvantageous cases, the patients are in danger
of developing a multi-organ deficiency syndrome (MODS) by an uncontrolled inflammatory reaction, by intravasal volume loss
and by a myonephropathic systemic reaction. Clinically, the patients suffer a disproportionate amount of pain, followed by
neurological signs. Especially in noncompliant patients, tissue pressure measurement is useful. Resuscitation of the circulation
as well as splitting of casts is important. In case of a manifest cs, dermatofasciotomy has to be performed as an emergency
operation. Even if cs is diagnosed early and fasciotomy is carried out early, the development of sequellae cannot be avoided
in every single case.
相似文献
999.
Frédéric Bruckert Eric de Kerviler Anne-Marie Zagdanski Jean-Michel Molina Isabelle Casin A. Guermazi Janine Bédrossian Jacques Frija 《Skeletal radiology》1997,26(7):431-433
Bartonella henselae, previously called Rochalimaea henselae, is the causative agent of cat scratch disease (CSD) in immunocompetent subjects and bacillary angiomatosis in immunocompromised
ones. Bone lesions are common in bacillary angiomatosis, but not in CSD. We present the case of a patient with a renal transplant
treated by immunosuppressive therapy who developed a sternal abscess with a histological pattern of CSD. The CT pattern was
that of a lytic bone lesion with adjacent fluid collection. The diagnosis was made on the basis of a polymerase chain reaction
amplification performed on bone material. Bartonella henselae is a newly described bacteria that causes CSD in a normal host and bacillary angiomatosis in immunocompromised patients. We
report a case of an osteolytic lesion of the sternum with adjacent fluid collection related to CSD, which occurred in a patient
with a renal transplant. 相似文献
1000.
B. Bernardi C. Fonda E. Franzoni E. Marchiani E. Della Guistina R. A. Zimmerman 《Neuroradiology》1994,36(6):477-479
A case of infantile Krabbe's disease was first recognised as areas of relatively increased density on CT in the thalamus lateral geniculate body and dentate nucleus. These sites were subsequently shown on MRI to have a paramagnetic effect, being characterised by short T2 and T1. Subsequent examinations showed development of atrophy and high signal in white matter. 相似文献