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目的 观察Intralipid对内毒素所致的多形核白细胞氧自由基产生的影响,方法 取22例健康志愿者静脉血,采用Boyum法提取多核白细胞(PMN)并在体外培养,采用不同剂量的脂多糖(LPS)刺激PMN,并和不同剂量Intralipid共同作用,采用NBT还原剂试验测定氧自由基的产生量。结果 LPS刺激各组的NBT值明显高于非刺激组,而且NBT值与LPS浓度明显相关,Intralipid可明显浓度  相似文献   
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Summary Field stimulation of circular smooth muscle of guinea-pig stomach from the regions of the cardia and fundus caused contraction responses at low stimulation frequencies (0.25–1 Hz) with relaxation at higher frequencies (1–10 Hz), whilst tissues of the body and antrum responded with contraction throughout the frequency range. Atropine (10–9–10–8 M) antagonised the contraction responses of all tissues, with relaxation developing at higher concentrations (except for antral tissue). In contrast, metoclopramide (10–8–10–6 M) caused modest (cardia, fundus) or marked (body, antrum) enhancement of contractions to field stimulation, whilst domperidone (10–8–10–7 M), haloperidol (10–8–10–6 M), prazosin, propranolol and methysergide (10–8–10–6 M) failed to modify the contraction responses. However, whilst yohimbine and guanethidine failed to modify the contractions of the cardia, fundus and body tissues, those of the antral preparations were antagonised by nanomolar concentrations of yohimbine and by guanethidine (10–6–5×10–5 M). To optimise the relaxation responses for study, atropine was included in the physiological solution. Relaxation to field stimulation of preparations from the body and cardia, but not the fundus, was antagonised by reserpine pretreatment (5 mg/kg i.p., 24h), addition of guanethidine (10–5–10–4 M), phentolamine, prazosin or propranolol (10–7–10–6 M) (the effects of prazosin and propranolol being additive). Higher concentrations of haloperidol and domperidone antagonised the relaxation responses of the body preparations only. Metoclopramide, yohimbine and methysergide (10–8–10–6 M) were ineffective. Thus, it is concluded that the contractile effects of the 4 stomach areas to field stimulation reflects a major cholinergic involvement, with an additional 2-adrenoceptor contractile component in antral tissue. Relaxation responses of cardia and body tissue involve 2- and -adrenoceptors plus a further, unidentified, non-adrenergic component; the latter represents the total relaxation response of the fundic preparation.  相似文献   
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Mutations in the MECP2 (methyl-CpG-binding protein 2) gene are known to cause Rett syndrome, a well-known and clinically defined neurodevelopmental disorder. Rett syndrome occurs almost exclusively in females and for a long time was thought to be an X-linked dominant condition lethal in hemizygous males. Since the discovery of the MECP2 gene as the cause of Rett syndrome in 1999, MECP2 mutations have, however, also been reported in males. These males phenotypically have classical Rett syndrome when the mutation arises as somatic mosaicism or when they have an extra X chromosome. In all other cases, males with MECP2 mutations show diverse phenotypes different from classical Rett syndrome. The spectrum ranges from severe congenital encephalopathy, mental retardation with various neurological symptoms, occasionally in association with psychiatric illness, to mild mental retardation only. We present a 21-year-old male with severe mental retardation, spastic tetraplegia, dystonia, apraxia and neurogenic scoliosis. A history of early hypotonia evolving into severe spasticity, slowing of head growth, breathing irregularities and good visual interactive behaviour were highly suggestive of Rett syndrome. He has a de novo missense mutation in exon 3 of the MECP2 gene (P225L). The clinical spectrum and molecular findings in males with MECP2 mutations are reviewed.  相似文献   
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A national household probability sample of 4,023 adolescents aged 12 to 17 years was surveyed by telephone via structured clinical interview to determine the impact of familial substance use, sexual and physical assault, witnessed violence, depression and posttraumatic stress disorder (PTSD) on risk of smoking. Results indicated that familial substance use increased risk of smoking only for boys and sexual assault or depression increased risk of smoking only for girls. Age, Caucasian ethnicity, and experiencing physical assault or witnessing violence elevated risk of current cigarette use for both genders. By contrast, PTSD per se was not associated with increased risk of smoking, after the effects of other variables were controlled.  相似文献   
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Safety Behaviors of Abused Women After an Intervention During Pregnancy   总被引:1,自引:0,他引:1  
Objective: To evaluate an intervention protocol, administered during pregnancy, for increasing safety-seeking behaviors of abused women.
Design: Prospective, ethnically stratified cohort analysis.
Setting: Public prenatal clinics.
Participants: Pregnant women reporting physical or sexual abuse in the year before or during the present pregnancy. One hundred thirty-two women met study criteria, received the intervention, and were followed for 1 year after the completion of the pregnancy.
Intervention: Three education, advocacy, and community referral sessions that included information on safety behaviors.
Main outcome Measure: Adoption of safety behaviors by abused women. Safety behaviors were measured before the intervention, twice during pregnancy, and at 2, 6, and 12 months after completion of the pregnancy.
Results: Repeated measures analysis of variance showed a significant increase in adoption of each safety behavior (p < .0001), with most behaviors showing a significant increase after the first intervention session.
Conclusions: Pregnant women who were abused and were offered an intervention protocol report a significant increase in safety behavior adoption during and after pregnancy. Abuse during pregnancy is common. Identification of abuse and immediate clinical intervention that includes information about safety behaviors can result in safety behavior adoption that may prevent future abuse and increase the safety and well-being of women and infants.  相似文献   
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Abstract

The authors identify 39 common preoperative stressors found in 175 heart transplant candidates from two medical centers. Relevance of the 10 worst and 10 least stressors during the preop wait is discussed. The 10 worst stressors were finding out about the need for a transplant, having end-stage heart disease, family worrying, illness symptoms, waiting for a donor, uncertainty about the future, no energy for leisure activities, constantly feeling worn out, less control over life, and dependency on others. The impact of transplant waiting time on the perceived stressfulness of illness factors is also examined. One factor was more stressful for those waiting longer than the median time of 1 month; 16 factors were more stressful for those waiting less than 1 month. The novelty or familiarity of the factor seemed to influence the stressfulness ratings of many variables during the period of waiting for the transplant.  相似文献   
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