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51.
Slow-wave sleep increased in cats after administration of a 5-hydroxytryptamine (5-HT)-depleting dose of fenfluramine while it was decreased by p-chlorophenylalanine (pCPA), another 5-HT-depleting drug. Fenfluramine reversed the reduction in sleeping time resulting from pCPA administration and this reversal was blocked by AHR-3009, a 5-HT antagonist. These data suggest that although brain 5-HT levels may not be involved in the sedative action of fenfluramine, sleep was induced by an action on a tryptaminergic pathway.  相似文献   
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53.
Tarsal navicular stress fractures: radiographic evaluation   总被引:3,自引:0,他引:3  
Pavlov  H; Torg  JS; Freiberger  RH 《Radiology》1983,148(3):641-645
Tarsal navicular stress fractures are a potential source of disabling foot pain in physically active individuals. The diagnosis of tarsal navicular stress fracture requires a high index of clinical and radiographic suspicion because the fracture is only rarely evident on routine radiographs or standard tomograms. The radiographic diagnosis of a tarsal navicular stress fracture may require anatomic anteroposterior tomograms or a radionuclide bone scan with plantar views. Radiographic examinations of 23 fractures in 21 patients are evaluated.  相似文献   
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A randomized trial was conducted to test the efficacy and sufficiency of parent-child interaction therapy (PCIT) in preventing re-reports of physical abuse among abusive parents. Physically abusive parents (N=110) were randomly assigned to one of three intervention conditions: (a) PCIT, (b) PCIT plus individualized enhanced services, or (c) a standard community-based parenting group. Participants had multiple past child welfare reports, severe parent-to-child violence, low household income, and significant levels of depression, substance abuse, and antisocial behavior. At a median follow-up of 850 days, 19% of parents assigned to PCIT had a re-report for physical abuse compared with 49% of parents assigned to the standard community group. Additional enhanced services did not improve the efficacy of PCIT. The relative superiority of PCIT was mediated by greater reduction in negative parent-child interactions, consistent with the PCIT change model.  相似文献   
56.
The clinicopathological associations of 33 singleton infants who died with intraventricular haemorrhage (IVH) without hyaline membrane disease (HMD) ('IVH only') were compared with those of 39 infants who died with IVH+HMD over the same gestation range in order to determine what factors other than those related to HMD may contribute to the pathogenesis of IVH. The incidence of 'IVH only' was inversely related to gestational age in the Hammersmith birth population, whereas the incidence of IVH+HMD rose to a peak at 28-29 weeks' gestation. Infants with 'IVH only' lived longer on average than those with IVH+HMD despite a lower birthweight and shorter gestation. Infants who died in the first 12 hours from 'IVH only' had suffered severe birth asphyxia but in those who died later the main symptom was recurrent apnoea. Fewer infants with asphyxia but in those who died later the main symptom was.recurrent apnoea. Fewer infants with 'IVH only' were given alkali therapy or were connected to the ventilator as compared to those with IVH+HMD, but there were no differences in alkali therapy in those who lived for 12 hours or more. In the 'IVH only' group there was a high incidence of haemorrhage from other sites and of bacterial infections. It is suggested that, in the absence of HMD, extreme immaturity is the main factor determining the occurrence of IVH. Birth asphyxia, apnoeic attacks, haemorrhage, and infections may play subsidiary roles, possibly through development of metabolic acidosis.  相似文献   
57.
0 引言 人类免疫缺陷病毒 (human immunodeficiencyvirus,HIV) - 1编码的反式激活蛋白 TAT具有独特的跨膜运转方式 ,而且有转导速度快 ,效率高的特点 ,被称为蛋白转导结构域 (protein transduction domain,PTD) [1 ,2 ] .本研究用PCR扩增了慢性粒细胞白血病慢粒 bcr/ abl融合蛋白的基因片段 ,在其 5′端融合 PTD结构域的编码区后在大肠杆菌中进行了表达 .表达产物经纯化后 ,加入培养的 HL 6 0细胞 ,表达的蛋白可直接进入细胞内 .这一结果为用外源蛋白负载(L oading)免疫细胞提供了新的途径 .1 材料和方法1.1  DNA重组 人工合…  相似文献   
58.
The patient was a 27-year-old male with short stature, borderline mental deficiency, strabismus, and a short fourth metacarpal. His karyotype showed deletion of the short arm of a chromosome 18 as the result of de novo fusion centric translocation between chromosomes 13 and 18 (45,XY, --13, --18, +t(13;18) (13qter yields cen yields 18qter).  相似文献   
59.
Sternocostoclavicular hyperostosis: a review and report of 11 cases   总被引:1,自引:0,他引:1  
Sternocostoclavicular hyperostosis is a benign ossifying diathesis of unknown etiology characterized by hyperostosis and soft-tissue ossification between the clavicles, anterior portion of the upper ribs, and manubrium, with variable hyperostosis or ankylosis in the spine and sacroiliac joints. Our cumulative experience with 11 cases is reported, with emphasis on radiographic features of the condition. Scintigraphic results in five patients and computed tomographic findings in one patient are presented. A review of the literature and our own material indicates that sternocostoclavicular hyperostosis may be more common than has been previously recognized.  相似文献   
60.
First rotavirus vaccine licensed: Is there really a need?   总被引:6,自引:0,他引:6  
The first rotavirus vaccine was licensed in the United States on 31 August 1998 for the prevention of severe rotavius diarrhea in children. Despite this landmark in new vaccines, many pediatricians and public health professionals in Europe are uncertain of the need for this vaccine for the routine immunization of infants. In Europe, ample evidence suggests that rotavirus is the most common cause of hospitalizations for severe diarrhea among children, but proper studies documenting the disease burden of rotavirus or th cost-effectiveness of a rotavirus immunization program have only been conducted in the United Kingdom following epidemiologic models used in the United States. All children are infected with rotavirus during their first few years of life, 30-50% of diarrheal hospitalizations among children <5 years are due to this agent, and, by the age of 5 years, between 1 in 40 and 1 in 77 children in Europe and the United States may be hospitalized for rotavirus. The first vaccine is a live, oral preparation combining four different serotypes of rotavirus and administered in three doses with other childhood immunizations. The good efficacy against severe rotavirus diarrhea, the low risk of adverse side effects and the positive costeffectiveness equation have led the two major immunization advisory groups in the U.S. to recommend this vaccine for routine use in American infants. European physicians and policymakers should re-examine the epidemiology and disease burden of rotavirus diarrhea now that an effective method of prevention is at hand. □ Childhood immunization, diseases, rotavirus, vaccination .  相似文献   
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