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AIM: To evaluate the clinical usefulness of early cortical phase images in the diagnosis of acute pyelonephritis and to compare the measurements of differential renal function obtained by both 99mTc ethylene dicysteine (99mTc-EC) and 99mTc dimercaptosuccinic acid (99mTc-DMSA). METHODS: Forty-three children who had undergone both 99mTc-EC and 99mTc-DMSA studies within 5 days of acute infection were studied. Cortical images of 99mTc-EC were obtained by the sum of the renogram frames achieved between the first 60-120 s of the renogram study. DMSA and EC images were visually interpreted using four points of semiquantitative ratings: 0, normal; 1, mild hypoactivity; 2, moderate hypoactivity with partial loss of margins; 3, marked hypoactivity with loss of cortical margins. Values for the differential renal function were obtained for both studies. RESULTS: DMSA detected a total of 109 lesions in 36 patients and EC detected 90 lesions with a sensitivity of 82.5%. 99mTc-EC successfully detected moderate-to-severe cortical lesions but was less effective with mild lesions (sensitivity 60%). Bland-Altman analysis demonstrated good agreement among the results for differential renal function (95% CI -0.26 to 0.96). CONCLUSION: 99mTc-EC early phase images detected most of the cortical lesions. Its sensitivity depends on the severity of the lesions. EC provided reliable information in the estimation of differential renal function.  相似文献   
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OBJECTIVE: In the present study, we aimed to evaluate menstrually related symptom changes in euthymic women with treatment-responsive bipolar disorder (BD) compared with healthy control subjects and investigate the presence of premenstrual dysphoric disorder (PMDD). METHODS: Thirty-four euthymic women with treatment-responsive BD on mood-stabilizers (lithium and/or valproate) for at least 6 months and 35 control subjects with no history of medical/mental disorder between ages of 18 and 35 years with regular menstrual cycles were prospectively followed up for at least two consecutive menstrual cycles using the Daily Record of Severity of Problems-Short Form (DRSP). Each subject was administered the retrospective self-report questionnaire, Premenstrual Assessment Form (PAF), in the first postmenstrual phase of the menstrual cycle. Venous blood samples were collected between 19 and 22 days of menstrual cycle to evaluate ovulation by measuring the serum progesterone levels. RESULTS: The differences in mean age, age of onset of menses, cycle length and bleeding length did not appear to be significantly meaningful between groups. In the retrospective assessment of premenstrual symptom changes, controls complained more than women with BD. More controls showed a 30% change in DRSP and in depressive and physical sub-groups than the women with BD. Controls demonstrated a significant increase compared with treatment-responsive BD patients in total, depressive, anxiety and attention sub-group scores of DRSP from the postmenstrual to the premenstrual phase, whereas the scores of vegetative symptoms of controls and women with BD did not differ significantly during one cycle or both. Significant menstrual cycle effect was observed in both groups. CONCLUSION: Within the limitations of the study, the results suggest that ongoing mood-stabilizing treatment may have a prophylactic effect against premenstrual symptom changes in women with treatment-responsive BD.  相似文献   
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We report 4 cases of malignant peripheral nerve sheath tumors (MPNST) with neurofibromatosis type 1 (NF1). Mean age was 29.5. Two of them had a family history. Three of them were male. All of them had enlarging mass and pain in the background of neurofibromas. Locations were popliteal, thigh and forearm. The masses were greater than 5 cm in diameter in each case. In two cases the mass was showing continuity with a nerve. One patient had a nonossifying fibroma as well as a MPNST. Wide excision and radiotherapy were applied to three of the patients. One of them did not take any therapy after surgical resection. Two of the patients died of lung metastases after a mean period of 12.5 months. In a majority of NF1 patients MPNST emerges from a preexisting neurofibroma. The patients with NF1 are at greatest risk for developing sarcomas, so they should be followed closely.  相似文献   
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OBJECTIVES: The pharmacokinetics of free L-dopa in blood and tissue of five parkinsonian patients with malignant melanoma was studied with microdialysis. In one case the effect of L-dopa treatment on 5-S-cysteinyldopa and the melanoma was studied. Gastric emptying and its effects on free L-dopa in blood were also investigated in one of the patients. METHODS: Five patients were given 100 mg L-dopa with 25 mg benserazide. Blood and dialysates from the circulation and fatty tissue were collected for analysis. [13C]-Octanoic breath test was used for analyzing gastric half-emptying time. RESULTS: Four of the patients had similar pharmacokinetic patterns for L-dopa and a significant (P < 0.05) increase of serum 5-S-cysteinyldopa occurring 30 min after L-dopa intake. Delayed L-dopa peaks and slow gastric half-emptying time were found in 1 patient. A dose-dependent increase of 5-S-cysteinyldopa occurred but no melanoma metastases were seen during long-term L-dopa therapy. CONCLUSION: L-dopa therapy increases 5-S-cysteinyldopa levels but does not seem to cause progress of melanomas. Gastric emptying impacts L-dopa pharmacokinetics.  相似文献   
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Microdialysis was investigated as a tool for the determination of the extracellular concentration of the pigment metabolite 5-S-cysteinyldopa in human melanoma transplanted to athymic mice. Histology of the tumour with the microdialysis probes in situ showed no tissue damage. With probes equipped with polycarbonate membranes (20 kD) extraction (relative recovery) was approximately 50% at pH 4.0 and flow rates of 1 microliter/min, but at pH 7.0 recoveries were markedly lower, particularly from serum. In a first series of human melanomas transplanted to athymic mice low concentrations of 5-S-cysteinyldopa were detected in only two out of ten dialysates and were not detected in the other eight. Utilizing devices constructed for comparison of membrane characteristics in vitro we found about 4-fold higher recoveries with cuprophane and polyamide membranes than with polycarbonate membranes. Therefore newly constructed microdialysis probes (CMA/11) with cuprophane membranes were tested in vitro and gave recoveries of 38-48% from Ringer-Acetate solutions and 22-31% from serum, and the pH effects were low. When these probes were utilized in a second series of melanomas transplanted to athymic mice, 5-S-cysteinyldopa could easily be quantified in 10/10 experiments. A steady-state level of the dialysate 5-S-cysteinyldopa concentration was reached after 45 min.  相似文献   
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