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101.
A rapidly growing body of data suggests that abnormalities in serotonergic function might be involved in the pathophysiology of schizophrenia and that serotonergic mechanisms play a role in the therapeutic effects of antipsychotics. The activity of the serotonin transporter (5-HTT), as determined by [(3)H]5-HT uptake to blood lymphocytes, was measured in 38 medicated schizophrenia patients (15 of them treated with typical antipsychotics and 23 treated with atypical antipsychotics) and 15 healthy control subjects. In addition, the pharmacodynamic characteristics of platelet 5-HTT were assessed by [(3)H]citalopram binding. There were no significant differences in the density (B(max)) of platelet [(3)H]citalopram binding sites between the three groups. Similarly, the dissociation constant (K(d)) values were indistinguishable. There were no significant differences in the maximal uptake velocity (V(max)) of [(3)H]5-HT to fresh lymphocytes between the three groups. The affinity (K(m)) values of 5-HT to the 5-HTT were significantly higher in schizophrenia patients treated with typical antipsychotics compared with control subjects. The K(m) values in schizophrenia patients treated with atypical antipsychotics were significantly lower compared with those observed in the group of schizophrenia patients treated with typical antipsychotics; however, they were comparable to values in the control group. The high values of K(m) associated with typical antipsychotic treatment may be relevant to the high risk of developing extrapyramidal side effects (EPS). The role of the various components of the serotonergic system in the etiopathology of schizophrenia and the mechanisms by which antipsychotics achieve their therapeutic effects need to be further evaluated.  相似文献   
102.
A large body of literature indicates that disturbances of central serotonin (5-HT) function play an important role in aggressive behavior. Results from open-label and placebo-controlled trials as well as the reported inverse relationship between 5-HT function and aggression in human subjects, suggest that reduced 5-HT activity is associated with aggressive behavior. The activity of the 5-HT transporter (5-HTT), as determined by [3H]5-HT uptake to blood lymphocytes, was measured in 20 currently aggressive and 20 non-aggressive male schizophrenia patients. In addition, the pharmacodynamic characteristics of platelet 5-HTT were assessed by [3H]citalopram binding.

There were no significant differences in the density (Bmax) of platelet [3H]citalopram binding sites between the two groups. Similarly, the dissociation constant (Kd) values were indistinguishable. The maximum uptake velocity (Vmax) of [3H]5-HT to fresh lymphocytes and the Km values of the 5-HT to the transporter were significantly higher in currently aggressive compared to the non-aggressive schizophrenia patients. The association of high Vmax values with current aggressive behavior provides further support to the involvement of the 5-HTT in aggressive behavior as well as to the efficacy of 5-HTT blockers in the control of aggression. The role of the various components of the serotonergic system in the pathophysiology and treatment of aggressive behavior in schizophrenia needs to be further evaluated.  相似文献   

103.
OBJECTIVE: To present a case series of vestibular symptoms appearing after combined sailing and diving activity, and to discuss the differential diagnosis and the workup algorithm. STUDY DESIGN: Case series. SETTING: Tertiary referral center. PATIENTS: Three patients aged 25 to 31 years suffering from unsteadiness and movement sensations after sailing and scuba diving. INTERVENTIONS: Neurotologic evaluation and recompression therapy in a hyperbaric chamber. MAIN OUTCOME MEASURES: The increasing popularity of marine sports and leisure activities has resulted in the exposure of a growing number of people to unique abnormalities not encountered under terrestrial conditions. The otolaryngologist who is involved in the care of these patients is required to diagnose and treat diving-related sinus and ear injuries such as barotrauma and decompression sickness, and also to be familiar with sailing-related disorientation syndromes such as seasickness and mal de debarquement. Treatment modalities for the various abnormalities differ significantly, and early commencement of treatment is often crucial for a successful outcome. CONCLUSION: Whenever doubt exists, recompression treatment must be instituted as soon as possible because of the potential for severe sequelae if the patient is left untreated, and because the risks involved in this therapy are minimal.  相似文献   
104.
105.
BACKGROUND: Obstructive sleep apnea syndrome is common in children with Down syndrome (DS). Little is known about sleep patterns, especially arousals, awakenings, and movements during sleep in children with DS. OBJECTIVE: To determine the characteristics of sleep disorders in children with DS and to define the associations between respiratory disturbance and arousals, awakenings, and movements. METHODS: The study included 23 children with DS, compared with 13 children with primary snoring. All underwent a 6- to 8-hour sleep study. RESULTS: The respiratory disturbance index was significantly higher in the children with DS (2.8 +/- 2.3 events/h vs 0.6 +/- 0.4 events/h; P <.05). Sleep was significantly fragmented in children with DS, who had a significantly higher arousal/awakening (A/Aw) index (24.6 +/- 7.9 events/h) compared with the comparison group (17.6 +/- 4.0 events/h) (P <.02). A higher percentage of jerks associated with A/Aw and respiratory event-associated A/Aw was observed in patients with DS (45.2% +/- 25% and 8.6% +/- 6.4%, respectively) compared with the control patients (10.2% +/- 4.5% and 1.5% +/- 2.1%) (P <.02). The median length of occurrences of stage 2 sleep was 27% shorter in the DS group (P <.03). The number of shifts from "deeper" to "lighter" stages of non-rapid eye movement sleep was 30% greater (P <.02) in the DS group. CONCLUSION: Children with DS have significant sleep fragmentation, manifested by frequent awakenings and arousals, which are only partially related to obstructive sleep apnea syndrome.  相似文献   
106.
Cholesterol embolism is a serious disease with a high morbidity and mortality rate. There is no clear evidence that any specific treatment helps this syndrome. We report a patient who developed acute renal failure due to cholesterol crystal embolism following percutaneous transluminal angioplasty of a renal artery. Treatment with iloprost for peripheral symptoms of cholesterol emboli resulted in rapid resolution of toe cyanosis, decrease in leg pain and a significant decrease in serum creatinine shortly after initiation of treatment. One month after initiation of iloprost therapy, skin signs of cholesterol emboli disappeared and leg pain diminished. Gradually reduction in serum creatinine level was also observed (from 390 to 160 micromol/L). Eighteen months after the arteriography, the patient had stable renal function with creatinine levels of 150-160 micromol/L, and he was asymptomatic.  相似文献   
107.
OBJECTIVES: We examined risk factors for long-term homelessness among newly homeless men and women who were admitted to New York City shelters in 2001 and 2002. METHODS: Interviews were conducted with 377 study participants upon entry into the shelter and at 6-month intervals for 18 months. Standardized assessments of psychiatric diagnosis, symptoms, and coping skills; social and family history; and service use were analyzed. Kaplan-Meier survival analysis and Cox regression were used to examine the association between baseline assessments and duration of homelessness. RESULTS: Eighty-one percent of participants returned to community housing during the follow-up period; the median duration of homelessness was 190 days. Kaplan-Meier survival analysis showed that a shorter duration of homelessness was associated with younger age, current or recent employment, earned income, good coping skills, adequate family support, absence of a substance abuse treatment history, and absence of an arrest history. Cox regression showed that older age group P<.05) and arrest history (P<.01) were the strongest predictors of a longer duration of homelessness. CONCLUSIONS: Identification of risk factors for long-term homelessness can guide efforts to reduce lengths of stay in homeless shelters and to develop new preventive interventions.  相似文献   
108.
109.
Dermatoses of the male genital area are widely diverse clinically and etiologically. Both dermatologists and urologists are involved in diagnosing and treating those dermatoses. This article will focus mainly on the important or commonly encountered entities classified according to their etiology as infectious, inflammatory, autoimmune, vascular, nervoid or other.  相似文献   
110.
The classical literature on endocrine effect on voice considers oral contraceptives (OCs) as a risk factor for voice. However, recent studies revealed no adverse effect of new-generation OCs on voice. It was also suggested that OCs could improve specific voice characteristics via different mechanisms. The aim of the present study was to evaluate the effect of OCs on voices of women who use different formulations containing drospirenone (n=10), desogestrel (n=9) and gestodene (n=10). Acoustic voice measures of the 29 women were evaluated twice during the menstrual cycle. Fundamental frequency, frequency as well as amplitude stability and noise characteristics were measured using a computerized voice analysis program. Results indicated that vocal stability and quality were similar in the three groups tested. Marginal differences were observed between the drospirenone group and the other two groups. This preliminary observational study indicates that although drospirenone was previously shown to reduce water retention, this effect was not found to directly influence voice characteristics of women who use OCs.  相似文献   
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