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91.
Agenesis of the corpus callosum is a complex malformation of the brain that has been associated with varying degrees of limbic system maldevelopment. We retrospectively reviewed the records of 11 patients with callosal agenesis (seven total, four partial) who underwent magnetic resonance (MR) imaging, with particular attention to the associated malformations of the limbic system. Comparison was made with selected images from MR examinations of healthy volunteers and with necropsy specimens from other patients with callosal agenesis. Ten of 11 patients demonstrated limbic anomalies (severe motion artifact precluded evaluation of these structures in one patient). MR depicted not only the abnormalities intrinsic to callosal agenesis but also the frequently associated malformations of the limbic system.  相似文献   
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PURPOSE: The purpose of this investigation was to determine the relationship between arthroscopically diagnosed synovitis and adhesions in a population of patients with significant limitation of mandibular opening and temporomandibular joint pain. PATIENTS AND METHODS: Temporomandibular joint arthroscopy was performed on 126 joints in 80 patients (female:male = 5.7:1; mean age = 35.5 years; mean duration of symptoms = 50 months). All patients were diagnosed with severe temporomandibular joint disease recalcitrant to conservative therapy. Each joint was evaluated arthroscopically for the presence of synovitis and adhesions. Chi-squared analysis was performed to determine if there was a significant relationship between the presence of synovitis and adhesions. RESULTS: Diagnostic arthroscopic examination showed the following: no synovitis and no adhesions in 18/126 joints (14%), no synovitis with adhesions present in 33/126 joints (26%), synovitis with no adhesions in 13/126 joints (10%), and synovitis and adhesions present in 62/126 joints (49%). Statistical analysis showed a significant relationship between arthroscopically diagnosed synovitis and adhesions. CONCLUSION: Synovitis and adhesions are commonly present in the temporomandibular joints of patients requiring arthroscopic surgery due to painful limitation of mandibular movement. Excessive mechanical stress on the temporomandibular joint leads to maladaptive responses in the articular and synovial tissues, ultimately leading to synovitis, osteoarthritis and the formation of adhesions. An understanding of the pathogenic mechanisms that lead to synovitis, osteoarthritis and adhesions has important clinical implications for the nonsurgical as well as surgical management of patients suffering from these disorders.  相似文献   
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We reviewed clinical presentation, investigations, therapy, prognosis and outcome of 232 patients with primary (AL) cardiac amyloidosis. There were 142 men and 90 women. Median age at presentation was 59 years (range 29-85). AL heart disease was unusual both in patients under the age of 40 (3.0%) and in non-Caucasians (6.5%). Fatigue and weakness were the commonest presenting symptoms. Hallmark features of periorbital ecchymoses and macroglossia were present in 12.5% and 27.2%, respectively. AL cardiac amyloidosis was unusual in isolation (3.9%), and most frequently patients had features of multiorgan dysfunction; heavy proteinuria and features of malabsorption predominating in this respect. Heart involvement represents the worst prognostic indicator, with a median survival from diagnosis of 1.08 years, falling to 0.75 years with the onset of heart failure. Current therapeutic procedures appear to prolong survival, with left ventricular wall thickness, mass and ejection fraction on echocardiography and late potentials on signal averaged electrocardiography of use in prognostic stratification. Cardiac involvement from AL amyloidosis is rapidly fatal. It should be suspected in all patients with heart failure who have wall thickening on echo, normal chamber sizes, low EKG voltages and evidence suggesting a multisystem disease.   相似文献   
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Prostaglandin F2 alpha (PGF2 alpha) binds specifically to a partially purified membrane preparation from rat corpora lutea. The high affinity, low capacity binding component asa a Kd = 4.7 nM and has a capacity of 0.38 pmol/mg protein. Binding kinetics were temperature-dependent with an association rate constant of 2.5 x 10(5) 1/mol-sec and a dissociation rate constant of 4.3 x 10(-4) sec-1 at 22 degrees C. Little competition for binding was shown by other prostaglandins and prostaglandin metabolites; the PGF2 alpha analogue ICI 81008 (16-m-trifluoromethylphenyl-prostaglandin F2 alpha) showed a binding affinity similar to that of PGF2 alpha. The specific binding of PGF2 alpha to luteal cell membranes was confirmed by electron microscopy using a ferritin--PGF2 alpha conjugate. Ferritin--PGF2 alpha was found predominantly on luteal cell surfaces; little binding occurred on other types of cells present. These data demonstrate specific binding of PGF2 alha to rat luteal membranes. It is suggested that the luteolytic action of PGF2 alpha in the rat may be receptor-mediated.  相似文献   
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The effect of upper airway surgery on voice.   总被引:2,自引:0,他引:2  
OBJECTIVE: Our goal was to assess patient perception and acoustic characteristics of voice before and after upper airway surgery. STUDY DESIGN AND SETTING: We conducted a prospective assessment of 44 surgical patients preoperatively and postoperatively at a tertiary care, academic hospital. Operations included septoplasty and turbinectomy (n = 28) and septoplasty, turbinectomy, uvulopalatopharyngoplasty, and tonsillectomy (n = 16). Patient opinion measures included Voice Handicap Index score, perception of vocal resonance, and change in voice. Acoustic measures included assessment of the relative amplitude of selected formants (resonances) of the vocal tract. RESULTS: Mean Voice Handicap Index scores were unchanged after surgery. Nine patients (20%) perceived their voice to be improved after surgery. None perceived the voice to be worse. Postoperative changes in relative formant amplitudes were statistically significant. These changes caused the acoustic features to become more representative of normative data than the preoperative values. CONCLUSION: Upper airway oeprations can affect acoustics and perception of voice. SIGNIFICANCE: Patients are unlikely to perceive a change in voice as a result of upper airway surgeries, but in those cases where a difference is perceived, it is likely to be a positive change.  相似文献   
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