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BACKGROUND AND OBJECTIVE: Contradictory and confusing reports on serum dehydroepiandrosterone (DHEA) levels in schizophrenia led us to compare the serum concentration of its precursor, pregnenolone (PREG), between medicated schizophrenia patients and healthy subjects. The neurosteroid levels were monitored for two months and the relationship of these neurosteroids with schizophrenic symptomatology, emotional distress, and anxiety was examined. METHOD: We determined blood levels of PREG, and DHEA in 15 schizophrenia patients and 12 healthy controls at four time points: at the start of the study, after 2, 4 and 8 weeks. Analysis of covariance and canonical correlations across four time points were applied. RESULTS: Controlling for age, serum concentrations of PREG were lower, while the DHEA level and the molar ratio values of DHEA/PREG were higher in schizophrenia patients compared to healthy controls. Both levels of PREG and DHEA and their molar ratio did not change significantly during the study's period either among schizophrenia patients or healthy controls. The blood levels of PREG appear to be associated with trait-anxiety scores in the schizophrenia patients, while associations of clinical symptoms with two neurosteroids did not reach a significant level when the confounding effect of emotional distress, and anxiety scores was controlled. CONCLUSION: Low serum pregnenolone concentrations in schizophrenia appear to be associated with trait-anxiety scores independent of symptoms. Further research into the role of pregnenolone in schizophrenia is warranted.  相似文献   
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Gastrointestinal stromal sarcomas   总被引:2,自引:0,他引:2  
BACKGROUND: Gastrointestinal stromal sarcomas are a rare group of malignancies originating in the bowel wall. METHODS: The treatment of 12 patients with gastrointestinal stromal sarcoma who underwent operation between 1994 and 1998 was reviewed. RESULTS: Eight tumours originated in the stomach; others were in the small bowel or rectum. Five of the tumours were of myogenic origin, two were gastrointestinal autonomic nerve tumours, one was a mixed neural-myoid tumour, and four could not be differentiated. Complete resection was possible in ten patients; in two of the ten en bloc resection of adjacent organs was required to ensure adequate margins. The tumours in the remaining two patients were irresectable because of diffuse intra-abdominal metastatic disease. All patients who underwent complete resection were alive after 4-48 (median 14) months. Two of the ten patients developed recurrence, which was reresected completely. The patients with metastatic disease died less than 1 year after operation. CONCLUSION: Aggressive surgical resection, achieving complete resection, can lead to prolongation of life and may be a potential cure for patients with gastrointestinal stromal sarcoma.  相似文献   
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Although it is known that selective serotonin reuptake inhibitors (SSRIs), as other antidepressants, elevate mood only after 3-4 weeks of treatment, the mechanism responsible for this delay is not understood. SSRIs have been demonstrated to alter the levels of neurosteroids such as allopregnanolone (THP) which possess anxiolytic and mood-elevating properties. We compared the effect of 9 and 21 days i.p. administration of paroxetine, a potent SSRI, on the synthesis of THP and its precursor, 5alpha-dihydroprogesterone (DHP), in the mouse cortex, hypothalamus and olfactory bulb. Cortex, olfactory bulb and hypothalamus synthesized levels of DHP were significantly raised after 9 days of paroxetine administration, whereas a significant rise in the THP synthesized level was observed only after 21 days of treatment. Peripheral synthesis of DHP, measured by the level in serum, significantly increased after 9 days, but reverted to normal values after 21 days. No increase was detected in serum THP levels either after 9 or 21 days treatment. Differences in peripheral and brain synthesis indicates independence in brain synthesis. The data indicate that paroxetine administration differentially increases [3H]DHP and [3H]THP content, depending on the duration of the treatment. Our results suggest that brain THP may be involved in the antidepressive and anxiolytic activity of paroxetine.  相似文献   
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BACKGROUND: Familial dysautonomia is a hereditary multisystemic disease primarily affecting people of Ashkenazi Jewish descent. Musculoskeletal problems are related to gait disorders, spinal deformities, foot deformities, fractures, and arthropathies. METHODS: The charts and radiographs of 136 patients who ranged in age from three months to forty-six years (mean, sixteen years) were reviewed. Sixty-four patients were available for follow-up examination. RESULTS: Spinal deformity was the most common orthopaedic problem and was diagnosed in seventy-eight patients starting at the age of four years, with a prevalence of 86 percent (forty-eight of fifty-six) by the age of fifteen years. Forty-one (53 percent) of the seventy-eight patients had scoliosis only, thirty-four (44 percent) had kyphoscoliosis, and three (4 percent) had kyphosis only. Bracing was accompanied by emotional, pulmonary, and skin problems, leading to a high rate of noncompliance and progression of the curve. Twenty-four patients had an operation at a mean age of thirteen years (range, five to eighteen years): twenty patients had posterior spinal arthrodesis, and four had combined anterior and posterior arthrodesis. Fifteen patients had a total of nineteen complications, of which seven were systemic and twelve were related to the spinal fixation. Eight patients had revision surgery. At the time of the surgery, scoliosis was corrected from a mean of 55 degrees to a mean of 35 degrees and kyphosis was corrected from a mean of 69 degrees to a mean of 61 degrees. After a mean duration of follow-up of sixty-five months, scoliosis measured 49 degrees (range, 18 to 62 degrees) and kyphosis measured 67 degrees (range, 30 to 115 degrees). Postoperative progression of the deformity was caused by failure of the instrumentation or progression in unfused segments. Walking was delayed in 72 percent (ninety-four) of the 130 patients who were of walking age. All sixty-four of the patients who were examined had an ataxic gait. Foot deformities were found in sixteen patients, six of whom were treated surgically. Two patients had Charcot joints. Fifty-five patients sustained at least one fracture before skeletal maturity, with a mean of 1.5 fractures per patient. All but one of the fractures was treated nonoperatively, and fracture-healing was often accompanied by profuse callus formation. CONCLUSIONS: Spinal deformity is common in patients with familial dysautonomia. Bracing is of questionable benefit, and surgical intervention should be considered once curve progression is well documented. Arthrodesis should be extended as far proximally as possible to prevent junctional kyphosis. Swelling and warmth in a limb should raise suspicion of an undiagnosed fracture.  相似文献   
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Nineteen female adolescent inpatients diagnosed with anorexia nervosa, restricting type (AN-R) and 16 non-eating disordered (ED) controls were assessed for plasma dehydroepiandrosterone (DHEA), dehydroepiandrosterone-sulphate (DHEA-S), and cortisol levels, and for eating-related and non-eating-related psychopathology. AN-R patients were assessed at admission, 1 month and 4 months following hospitalization. The non-ED controls were assessed once. No baseline between-group differences were found in plasma cortisol, DHEA, and DHEA-S levels, whereas the patient group had a significantly lower Cortisol/DHEA-S ratio and elevated scores on most psychopathological parameters. A significant increase was found in the body mass index of the AN-R patients at 4 months post-hospitalization, accompanied by a decrease in plasma cortisol levels and a trend towards decreased Cortisol/DHEA and Cortisol/DHEA-S ratios, whereas no change occurred in psychopathology. The difference in Cortisol/DHEA-S ratio between AN-R patients and non-ED controls, and the different patterns of change in cortisol vs. DHEA(-S) levels following weight restoration, may in part account for the feeding difficulties in AN, particularly during refeeding.  相似文献   
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Previous studies had suggested that norepinephrine (NE) and its precursors dopamine (DA) and L-DOPA acted similarly on iodine metabolism of isolated thyroid cells. Present studies indicate that this similarity extends to the inhibition by catecholamines of TSH-stimulated T4 release by mouse thyroids incubated in vitro. DA (5 X 10(-4) M), like NE, shown previously, inhibits TSH-stimulated T4 release. This inhibition was reversed by the alpha-blockers phentolamine, prazosin, and yohimbine, but not by the beta-blocker L-propranolol. DU-18288 and diethyldithiocarbamate, inhibitors of DA beta-hydroxylase, did not reduce DA inhibition, suggesting that prior conversion to NE was not a condition for DA activity. Apomorphine, a dopaminergic agonist but not a NE precursor, acted like DA, and its inhibition was also reversed by alpha-blockers. Furthermore, sulpiride, a dopaminergic blocker, reversed DA and apomorphine inhibition of TSH stimulation. These results suggest that DA inhibits TSH-stimulated T4 release through both adrenergic and dopaminergic receptors. On the other hand, L-DOPA, exerting an inhibition like that of DA, was also reversed by alpha-blockers, but its activity was greatly diminished by carbidopa, an inhibitor of aromatic L-amino acid decarboxylase, the enzyme converting L-DOPA to DA. This indicated that L-DOPA had to be converted to DA for activity. Both DA and L-DOPA inhibited stimulation of T4 release induced by (Bu)2cAMP, suggesting that their effect was exerted at a locus distal to cAMP generation. Indirect confirmation of a cAMP-independent pathway was obtained when DA inhibited TSH-stimulated cAMP formation, but, contrary to T4 release, this inhibition was not reversed by dopaminergic or adrenergic blockers. Presumably, therefore, DA inhibition of TSH-stimulated cAMP production was not related to T4 release. We conclude that 1) DA inhibits TSH-stimulated T4 release in mouse thyroids via alpha-adrenergic and dopaminergic receptors; 2) L-DOPA has to be converted to DA to produce inhibition; and 3) cAMP is unlikely to be an intermediary in DA inhibition.  相似文献   
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BACKGROUND: Several reports have suggested that early chest tube drainage (CTD) may not be necessary in the treatment of severe pleural empyema (PE) in pediatric patients if appropriate antibiotic therapy and supportive care are provided. OBJECTIVES: A prospective open study to compare the short-term course of two treatment protocols of severe PE in pediatric patients. STUDY DESIGN: One group of 32 patients was treated with early insertion of a chest tube for CTD, and a second group of 35 patients was treated by a repeated ultrasound-guided needle thoracocentesis (RUSGT). The severity of the empyema was assessed by chest radiograph, the amount of fluid drained, the number of days the patient had experienced a fever, and the duration of antibiotic treatment. RESULTS: No significant differences were found between the two groups (RUSGT vs CTD) in all of the following measurements: mean (plus minus SD) duration of a temperature > or = 39 degreesC, 6.2 +/- 2.4 vs 6.5 +/- 1.8 days, respectively; mean duration of a temperature > or = 38 degreesC, 9 +/- 3.9 vs 8.2 +/- 4.5 days, respectively; fluid drained, 35.1 + 23.8 vs 30 +/- 28.2 mL/kg, respectively; duration of antibiotic treatment, 30 +/- 13.2 vs 30.2 +/- 7.3 days, respectively; and length of hospitalization and home IV treatment, 22 +/- 7.6 vs 24.2 +/- 7.5 days, respectively. A failure to respond to treatment occurred in three patients in the RUSGT-treated group and in five patients in the CTD-treated group. The failure to respond occurred in the RUSGT-treated group only in those patients with very large empyemas that caused mediastinal deviation. CONCLUSION: The treatment of PE by RUSGT is as efficacious as CTD, unless PE causes mediastinal deviation.  相似文献   
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