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1.
Vision in childhood   总被引:1,自引:0,他引:1  
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We report a case of a patient with CF who had a long history of recurrent distal intestinal obstruction syndrome. She had been treated with conventional treatment including gastrografin, n-acetyl cysteine, Klean prep and Picolax. She underwent a modified antegrade continence enema procedure. She currently irrigates her conduit every 2-3 days. She has had no further symptoms of distal intestinal obstruction syndrome.  相似文献   
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Pediatric acquired immune deficiency syndrome (AIDS) was known to be a new disease that could be acquired from the mother even before human immunodeficiency virus (HIV) was identified. The suggested routes of transmission of infection are intrauterine, perinatal--from contact with infected maternal genital secretions, or through breastfeeding. At this time the problem in Europe concerns primarily women in high-risk groups: intravenous drug abusers, prostitutes, women from countries where the prevalence of HIV is high, and women whose sexual partners are in a high-risk group. In the future, the infection may extend beyond women in high-risk groups as the disease becomes more prevalent in the community. It has been claimed that pregnancy accelerates symptoms in women who are HIV positive, yet this is based on only a series of case reports of severe infection in pregnancy and on the development of AIDS in asymptomatic women in pregnancy subsequent to the birth of an AIDS child. The only data capable of shedding some light on this issue would be a prospective followup of both pregnant and nonpregnant HIV-positive women from similar high-risk groups. Such a study is ongoing in the US. An increasing number of case reports suggest intrauterine transmission of infection. The following 3 case reports provide clear evidence of intrauterine transmission. Sprecher et al. (1986) detected HIV antigen in amniotic fluid and fetal tissues from a pregnancy termination at 15 weeks gestation in a woman with stage IV AIDS and Kaposi sarcoma. Lapointe et al. (1985) reported an infant born by cesarean section at 28 weeks gestation to a mother with terminal aids. A new dysmorphic syndrome recently has been described in children with symptomatic HIV infection (Marion et al., 1986). HIV has been isolated from cervical secretions (Fogt et al., 1986; Wofsy et al., 1986), which suggests that this cold be another source of infection. There is 1 report of isolation of HIV from the noncellular fraction of breast milk (Thirty et al., 1985). Several case reports have described acquired immunodeficiency in infants for whom the only known risk factor was neonatal transfusion from an individual later found to be suffering from AIDS. The risk of transmission from an infected mother to her infant is unknown, but the best available evidence comes from a study of children born to women who had previously given birth to a child with AIDS (Scott et al, 1985). Of 12 children, 4 developed AIDS or Aids-related complex. Clinical problems among children with AIDS or AIDS-related complex have been fully described. The fatality rate of children with AIDS is high, but the ultimate progress of children with less severe disease or who have asymptomatic infection is known.  相似文献   
5.
Clinical applications of electrical stimulation for effecting change in the damaged or disabled nervous system are in their infancy. This technique is extremely powerful, because any neural structure that is electrically excitable can potentially be affected. Although early attempts to apply electrical stimulation were limited by insufficient physiological knowledge and undeveloped technology, developments over the past two decades now provide a strong base for clinical applications. Clinical systems for bladder control and respiration have been in use for many years. Some applications of FES to restore hand function and walking are in multicenter testing, whereas many others are being studied for clinical feasibility at single sites. Applications are focusing on safety and efficacy, as well as on clinical outcome measures to address the issues posed by the regulatory and reimbursement processes. As clinical systems become more routine, issues of multiple system applications will need to be addressed. Present and future applications of functional electrical stimulation may be expected to significantly enhance independence and improve the quality of life for individuals with central nervous system dysfunction.  相似文献   
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A xenograft line, HX 53, has been established in immune-suppressed mice from a specimen of a lymph node metastasis in a patient with a histological diagnosis of seminoma but with markedly raised circulating levels of alpha-fetoprotein. Histological, immunocytochemical, and ultrastructural studies of this xenograft line have suggested that a solid variant of yolk sac carcinoma may exist, which morphologically resembles seminoma, or that a continuum of differentiation exists between seminoma and yolk sac carcinoma.  相似文献   
9.
We have investigated whether the phenotype of myogenic clones derived from satellite cells of different muscles from the transgenic immortomouse depended on muscle type origin. Clones derived from neonatal, or 6- to 12-week-old fast and slow muscles, were analyzed for myosin and enolase isoforms as phenotypic markers. All clones derived from slow-oxidative muscles differentiated into myotubes with a preferentially slow contractile phenotype, whereas some clones derived from rapid-glycolytic or neonatal muscles expressed both fast and slow myosin isoforms. Thus, muscle origin appears to bias myosin isoform expression in myotubes. The neonatal clone (WTt) was cultivated in various medium and substrate conditions, allowing us to determine optimized conditions for their differentiation. Matrigel allowed expressions of adult myosin isoforms, and an isozymic switch from embryonic alpha- toward muscle-specific beta-enolase, never previously observed in vitro. These cells will be a useful model for in vitro studies of muscle fiber maturation and plasticity.  相似文献   
10.
Functional neuromuscular stimulation (FNS) has been used in upper extremity neuroprostheses to provide grasp and release for quadriplegic individuals. The goal of this project was to determine the electrode/muscle input/output characteristics with the greatest influence on the grasp output. This was evaluated by simulating the grasp synthesis procedure, using a model of the electrode/muscle output as a function of stimulus level and joint angle. The parameters of this model were determined from experimental data from 112 electrodes. The grasp output for 500 different modelled pairs of electrodes were analysed, with each pair consisting of a thumb flexor and a thumb extensor. The simulation results indicate that the most influential electrode input/output characteristics are the output stiffness, defined as the change in force output for a unit change in joint angle at a constant level of stimulation, and the length dependency mean-squared error. Recruitment gain was found to be of secondary influence on the grasp output, and the threshold, force direction and non-linearity of the stimulus level to force relationship were found to have little influence on the grasp output. These results establish criteria for electrode selection and implantation for use in upper extremity FNS.  相似文献   
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