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31.
Antipsychotics and the risk of sudden cardiac death   总被引:10,自引:0,他引:10  
BACKGROUND: Antipsychotics have been associated with prolongation of the corrected QT interval and sudden cardiac death. Only a few epidemiological studies have investigated this association. We performed a case-control study to investigate the association between use of antipsychotics and sudden cardiac death in a well-defined community-dwelling population. METHODS: We performed a population-based case-control study in the Integrated Primary Care Information (IPCI) project, a longitudinal observational database with complete medical records from 150 general practitioners. All instances of death between January 1, 1995, and April 1, 2001, were reviewed. Sudden cardiac death was classified based on time between onset of cardiovascular symptoms and death. For each case, up to 10 random controls were matched for age, sex, date of sudden death, and practice. Exposure at the index date was categorized as 3 mutually exclusive groups of current use, past use, and nonuse. RESULTS: The study population comprised 554 cases of sudden cardiac death. Current use of antipsychotics was associated with a 3-fold increase in risk of sudden cardiac death. The risk of sudden cardiac death was highest among those using butyrophenone antipsychotics, those with a defined daily dose equivalent of more than 0.5 and short-term (相似文献   
32.
Electronystagmographic findings following cervical whiplash injuries   总被引:2,自引:0,他引:2  
A group of 262 patients suffering from the after-effects of an acceleration trauma of the neck were subjected to an extensive vestibular examination. 85% of the patients complained of some type of vertigo. The visual suppression test conducted during rotation showed pathology in 37% of the cases. Visual pursuit movements were affected in 43% of the cases. In a group of 41 patients the results obtained respectively 1 and 2 years after the accident were compared. There was no significant improvement of the findings. No oculomotor system pathology was found in 99 cases (38%), and no electronystagmographic pathology at all in 55 cases (21%). The study emphasized the fact that nystagmographic examinations are able to detect central vestibular dysfunction and is therefore a suitable method to prove pathology.  相似文献   
33.
Coronary blood flow regulation was studied in dogs with an intact or chronically decentralized intrinsic cardiac nervous system. We also examined the effect of angiotensin-converting enzyme inhibition (ACEI) on coronary autoregulatory pressure-flow relations and distribution of blood flow since the renin-angiotensin system may play a critical role in vasoregulation. Myocardial oxygen demand was reduced in the chronic decentralized dogs compared to the control dogs. The lower pressure limit of the autoregulatory pressure-flow relation was similar for the control and chronic decentralized dogs (47+/-2 and 44+/-7 mm Hg, respectively; p = NS). After ACEI, the lower pressure limit shifted leftward to 40 mm Hg (p=0.001) in both groups. Concomitant blockade of cyclooxygenase, bradykinin catabolism and nitric oxide synthase had no further effect on the lower pressure limit. Total myocardial blood flow was lower (p=0.001) in the chronic decentralized dogs compared to the control dogs, while transmural distribution of blood flow was preserved in both groups. The results show that even though myocardial oxygen requirements are lower in the chronically decentralized heart compared to controls, coronary autoregulation is maintained at levels observed in normally innervated hearts. The present findings indicate that intrinsic cardiac neurons contribute to coronary autoregulatory control and myocardial blood flow distribution even in the absence of cardiac connections to the central nervous system. In addition, in the chronic decentralized dog, ACEI allows the heart to work at lower coronary perfusion pressures while myocardial blood flow distribution is preserved.  相似文献   
34.
AIMS: To study neuropsychological functioning of newly diagnosed children with acute lymphoblastic leukaemia (ALL) within two weeks after diagnosis in order to determine the feasibility of a sibling controlled prospective study design. METHODS: Fifty consecutive patients (median age at testing 6.6 years, range 4-12) were included in a prospective, longitudinal, nationwide study. Treatment would include intrathecal and systemic chemotherapy according to the DCLSG ALL-9 protocol. Children were evaluated with an extensive neuropsychological battery including measures of intelligence, memory, attention, language, visual-constructive function, and fine-motor abilities within two weeks after start of the chemotherapy. The control group consisted of 29 healthy siblings (median age at testing 8.2 years, range 4-12), who were tested <4 weeks after the patients' assessment. RESULTS: Mean scores on Wechsler Intelligence Scales did not differ significantly between patients and siblings; mean IQ scores for both the patients and the controls were high average. To examine specific neuropsychological functions, norm scores based on the exact age were acquired by fitting procedures, but no significant differences were found. CONCLUSIONS: Neuropsychological assessment of patients during early hospitalisation is feasible. The results indicate no adverse effect of illness and psychological factors on IQ and neuropsychological functioning of patients with recently diagnosed ALL. The prospective design of this study of cognitive late effects of chemotherapy will allow discrimination between adverse sequelae of disease and treatment.  相似文献   
35.
Placental CRH plays a major role in the mechanisms controlling human pregnancy and parturition. Understanding how placental CRH production is regulated is therefore of importance. Previously we have shown that placental expression of CRH peptide and mRNA are inhibited by estrogens, in contrast to the stimulatory effects of estrogen on hypothalamic CRH production. Our current study found that in placental cells cotransfected with a CRH promoter construct and an estrogen receptor-alpha expression vector results in a differential regulation whereby 17beta estradiol (E2) decreased and the putative pure estrogen antagonist, ICI 182780,  相似文献   
36.
To assess the effect of surfactant replacement therapy (SRT) on the prevalence and severity of retinopathy of prematurity (ROP), we compared data from 160 SRT-treated preterm infants with data from 230 historic controls. The prevalence of ROP was 30.6% in the treatment group and 23.4% in the control group. Severe ROP (stages 3-4) was seen in 6.1% of the infants with ROP in the treatment group and 20.3% of the ROP patients in the control group. Surfactant therapy had no influence on the prevalence of ROP (odds ratio 1.4, 95% confidence interval 0.797-2.459, p = 0.242). However, SRT was associated with a decreased risk for severe ROP, compared to mild ROP (odds ratio 0.226, 95% confidence interval 0.056-0.905, p = 0.036). These data suggest that SRT is associated with a decreased risk for severe ROP.  相似文献   
37.
35 patients with a smooth, threaded acetabular Mecron type prosthesis were examined with the aid of a table top with wiremarkers and a fixed 30-degree wedge to allow for reproducible positioning. Under fluoroscopic control, pelvic and spot films were made. The inter- and intraobserver variability of anteversion and inclination angle measurements of the prostheses had a standard deviation of less than 1 degree. The method can be applied to other acetabular prostheses as well.  相似文献   
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