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BACKGROUND: The present study was aimed to define the gender ratio, familial occurrence, age of onset, precipitating factors, clinical types, nail and joint involvement of psoriasis in childhood and adolescence in Turkey. METHODS: A total of 61 children with psoriasis under 18 years old were evaluated retrospectively, for age, gender, age of disease onset, family history, concomitant disease, the clinical type of psoriasis, clinical localization, nail and joint involvement and treatment modalities. RESULTS: Of the patients, 23 (37.70%) were boys and 38 (62.30%) were girls. Mean age was 9.28 +/- 4.02 years in girls and 11.18 +/- 3.85 years in boys (9.96 +/- 4.03 years in all children). Mean age at the onset of the disease was 6.81 +/- 4.11 years in girls and 7.03 +/- 4.28 years in boys (6.89 +/- 4.14 years in all patients). In 14 (23%) cases, a positive family history was detected. The most frequent probable triggering factors were upper respiratory tract infections (14.8%) and positive throat culture for A group ss-hemolytic streptococcus (21.3%). Frequency of emotional stress and psychiatric morbidity were 54% and 9.8%, respectively. The most frequent localizations at onset were trunk (44.3%), extremities (54.0%), and scalp (36.0%). Three children (4.9%) had a history of dissemination from psoriatic diaper rash. In total, 51 (83.6%) patients presented with psoriasis vulgaris, eight (13.1%) with generalized pustular psoriasis, and the remaining two (3.3%) with erythrodermic psoriasis. CONCLUSION: The incidence of psoriasis among dermatological patients in childhood and adolescence was 3.8%. The disease tends to appear earlier in girls than boys. The authors suggested that stress and upper respiratory infections are the most important triggering factors in childhood and adolescence psoriasis.  相似文献   
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The effects of morphine tolerance-dependence and abstinence on 5-HT1A receptors in brain regions and spinal cord of the rat were determined. Tolerance to and physical dependence on morphine was induced in male Sprague-Dawley rats by implanting six morphine pellets (each containing 75 mg of morphine free base) during a seven day period. Two groups of rats were used for binding studies. In one group the pellets were left intact (tolerant-dependent) and in the other they were removed (abstinent). Rats were killed, and spinal cords and brains were excised. Brain was dissected into seven regions (amygdala, hippocampus, hypothalamus, striatum, midbrain, pons + medulla and cortex). 5-HT1A receptors were characterized by using [3H]8-hydroxy-di-n-propylaminotetralin [( 3H]DPAT) as the ligand and unlabelled 5-HT to determine the non-specific binding. In morphine and placebo tolerant-dependent rats the binding of [3H]DPAT to 5-HT1A receptors in brain regions and spinal cord did not differ. The Bmax value of [3H]DPAT in the hypothalamus of morphine abstinent rats was decreased by 61.9%. No change in Bmax value was observed in other brain regions and spinal cord. The Kd values were unaffected. Subcutaneous administration of DPAT produced hypothermia in rats from which pellets had been removed. The intensity of DPAT-induced hypothermic response was greater in morphine abstinent rats as compared to placebo abstinent rats. Since DPAT is believed to have a major action on the presynaptic 5-HT neurons, it is concluded that in morphine abstinent rats 5-HT1A receptors are down-regulated in hypothalamus, but in morphine tolerant-dependent rats they are unaffected.  相似文献   
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A 32-year-old male presented with progressive weakness and numbness of both upper limbs of one-month duration. The patient had weakness and wasting of small muscles of both hands with weak grip. Sensory system revealed graded sensory loss to pain, temperature and touch in C5 to T1 distribution and vibration and joint position sense from C5 to C8 in the both upper limbs. There was areflexia in the upper limbs while there was no motor or sensory deficit in the lower limbs. The cortical potential on stimulation of posterior tibial nerve was prolonged on both sides. On MR imaging of the cervical spine there was iso to low intense lesion which was hyperintense on T2-weighted imaging along the dorsal aspect of the cord extending from C2 to C6 level. The axial images showed involvement of the posterior column. The serum vitamin B12 level was found to be low. The patient responded to parenteral cyanocobalamine therapy and the radiological lesion subsequently resolved.  相似文献   
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Xanthotoxol (XT), 8-hydroxypsoralen, exhibited dose-graded sedative activity in dogs, cats, rats, mice and hamsters. At doses of 5-20 mg/kg intraperitoneally (i.p.) in cats and 3-100 mg/kg orally (p.o.) in dogs, XT blocked predatory mouse/rat killing behavior. In mice, XT (10-300 mg/kg i.p.) exhibited a dose-dependent reduction in locomotor activity but was less potent in this regard than reference diazepam (10-100 mg/kg i.p.). XT in mice (0.1-10.0 mg/kg i.p.) and in hamsters (0.1-10.0 mg/kg p.o.) antagonized amphetamine-induced hypermobility but was less potent than diazepam. XT elevated the electrical threshold in foot-shock-induced fighting behavior in rats. XT (0.1-30.0 mg/kg p.o.) potentiated pentobarbital-induced narcosis in hamsters at otherwise subeffective doses of pentobarbital. Conditioned avoidance responses in rats were not significantly altered with 1-3 mg/kg i.p. and 30-100 mg/kg p.o. doses of XT but 300 mg/kg p.o. blocked both conditioned and unconditioned response. Doses of 100-1000 mg/kg i.p. of XT in mice were used to study 48-h acute toxicity of XT and its LD50 was estimated to be 468 mg/kg. Doses of 10, 40 and 80 mg/kg p.o. were used to study the chronic toxicity of XT in rats for 6 months and no side effects or abnormalities in reproductive activity or endocrine integrity were noted. The F1 generation of rats from 6-month XT-treated parents were free of teratogenic effects.  相似文献   
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