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101.
102.
The CO2 laser, emitting at 10,600 nm in the extreme infrared wavelength has special advantages for ophthalmology: its hemostatic properties and its ability to cut, vaporize, and shrink tissue make it particularly effective on the external eye and adenexae. In particular, it can be used for layerwise removal of tissue on the conjunctiva, the sclera, and the lids. Energy and exposure time are especially important. Irradiation of sclera from enucleated globes showed that these two parameters have a direct effect on the depth of craters - the CO2 laser's typical impact - and the laser's thermal effect on tissue. Technical and practical observations and the clinical results of more than 80 cases treated with the CO2 laser are presented and discussed. The low-power CO2 laser is a useful ophthalmological tool which can partially replace conventional surgery and extend treatment indications.  相似文献   
103.
Many concerns surround the preparation of a person with spina bifida for a successful transition into adult life and responsibilities. A model of intervention must be based on developmental concerns and timely issues from infancy through all stages of development to young-adult life. This article discusses, within a developmental framework, issues of transition in relation to physical, social, emotional, and educational/vocational needs; it also presents a conceptual framework for the transition into adulthood. Guidelines were developed by incorporating expected outcomes of people with spina bifida and using a philosophical framework that encompasses the achievement of a balance among dependence, independence, and interdependence. This model is based on developmental issues from infancy through all stages of development to young-adult life. Using this framework for care, the rehabilitation nurse can feel confident that the needs of clients with spina bifida and similar chronic conditions are being met.  相似文献   
104.
p < 0.01). Cumulative combined primary patency at 1 year by life-table methods was 82 ± 10% in the staged group and 83 ± 9% in the simultaneous group (p= 0.79). Mean follow-up was 13 ± 6 months. There is a role for balloon angioplasty and stent placement in operative revascularization of ischemic limbs in selected patients: patency was similar to that produced with the staged approach while the length of stay was shorter. Intraoperative balloon angioplasty is safe and effective and stents permit a measure of control in assuring an optimal intraoperative postangioplasty result.  相似文献   
105.
The exact role of the basal ganglia in both the motor and non-motor domains has proven elusive since it is virtually impossible to refer to its function in isolation of cortical, and especially frontal cortical circuits. The result is that we often speak of frontal-striatal circuits and functions but this still leaves us in the dark when trying to specify basal ganglia information processing. A critical review of the data from both basic science and clinical studies suggests that we should break down processing along a temporal continuum, including the domains of context, sequential information processing, and feedback or reinforcement (i.e., the consequences of action). This analysis would cut across other theoretical constructs, such as attention, central executive, memory, and learning functions, traditionally employed in the neuropsychological literature. Under specified behavioral constraint, the basal ganglia can then be seen to be involved in fundamental aspects of attentional control (often covert), in the guidance of the early stages of learning (especially reinforcement-based, but also encoding strategies in explicit paradigms), and in the associative binding of reward to cue salience and response sequences via dopaminergic mechanisms. Parkinson's disease is considered to offer only a limited view of basal ganglia function due to partial striatal depletion of dopamine and the potential involvement of other structures and transmitters in its pathology. It is hoped that the present formulation will suggest new heuristic research strategies for basal ganglia research, permitting a closer link to be established between neurophysiological, functional imaging and neuropsychological paradigms.  相似文献   
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107.
Behavioral disturbances have been reported with subthalamic (STN) deep brain stimulation (DBS) treatment in Parkinson's disease (PD). We report correlative functional imaging (fMRI) of mood and motor responses induced by successive right and left DBS. A 36-year-old woman with medically refractory PD and a history of clinically remitted depression underwent uncomplicated implantation of bilateral STN DBS. High-frequency stimulation of the left electrode improved motor symptoms. Unexpectedly, right DBS alone elicited several reproducible episodes of acute depressive dysphoria. Structural and functional magnetic resonance imaging (fMRI) imaging was carried out with sequential individual electrode stimulation. The electrode on the left was within the inferior STN, whereas the right electrode was marginally superior and lateral to the intended STN target within the Fields of Forel/zona incerta. fMRI image analysis (Analysis of Functional NeuroImages, AFNI) contrasting OFF versus ON stimulation identified significant lateralized blood oxygen level-dependent (BOLD) signal changes with DBS (P < 0.001). Left DBS primarily showed changes in motor regions: increases in premotor and motor cortex, ventrolateral thalamus, putamen, and cerebellum as well as decreases in sensorimotor/supplementary motor cortex. Right DBS showed similar but less extensive change in motor regions. More prominent were the unique increases in superior prefrontal cortex, anterior cingulate (Brodmann's area [BA] 24), anterior thalamus, caudate, and brainstem, and marked widespread decreases in medial prefrontal cortex (BA 9/10). The mood disturbance resolved spontaneously in 4 weeks despite identical stimulation parameters. Transient depressive mood induced by subcortical DBS stimulation was correlated with changes in mesolimbic cortical structures. This case provides new evidence supporting cortical segregation of motor and nonmotor cortico-basal ganglionic systems that may converge in close proximity at the level of the STN and the adjacent white matter tracts (Fields of Forel/zona incerta).  相似文献   
108.
The purpose was to measure the effects of postchemotherapy nausea and vomiting (PCNV) on health-related quality of life (HQL) in patients receiving either moderately or highly emetogenic chemotherapy. The study sample consisted of 832 chemotherapy-naive patients with cancer who received either moderately or highly emetogenic chemotherapy as part of multicenter trials of new antiemetics. The patients completed the self-report European Organization for Research and Cancer (EORTC) core Quality of Life Questionnaire (QLQ-C30) before chemotherapy (baseline) and 1 week (day 8) and 2–4 weeks after chemotherapy. They also completed a self-report nausea and vomiting (NV) diary for 5–7 days after chemotherapy. To determine the effects of PCNV on HQL, the change in scores between the baseline and day 8 HQL assessments was calculated for each domain and symptom in the QLQ-C30 and compared in four subgroups of patients: those with both nausea and vomiting, those with nausea but no vomiting, those with no nausea but with vomiting, and those with neither nausea nor vomiting. The group with both nausea and vomiting showed statistically significantly worse physical, cognitive and social functioning, global quality of life, fatigue, anorexia, insomnia and dyspnea as compared to the group with neither nausea nor vomiting (0.0001<P<0.05). Patients with only nausea but no vomiting tended to have less worsening in functioning and symptoms than those having both nausea and vomiting. Increased severity of vomiting (>2 episodes) was associated with worsening of only global quality of life and anorexia as compared with 1–2 episodes of vomiting (0.0001<P<0.01). By 2–4 weeks after chemotherapy all HQL scores had either returned to their baseline levels or were better than baseline. PCNV adversely affects several quality-of-life domains, but patients with only nausea experience less disruption than do those with both nausea and vomiting. Patients with 1–2 episodes of vomiting experience almost the same degree of disruption of HQL as do patients with more than 2 episodes of vomiting.  相似文献   
109.
110.
Summary. Information concerning 9919 singleton pregnancies delivered in Jamaica in the 2-month period of September and October 1986 and surviving the early neonatal period were compared with 1847 singleton perinatal deaths occurring in the 12-month period from 1 September 1986 to 31 August 1987, classified according to the Wigglesworth schema.
Logistic regression was used to assess features of antenatal and intrapartum care that were associated with the different groups of perinatal death after taking account of environmental, maternal and medical factors.
In Jamaica, 67% of all mothers took iron during pregnancy. These mothers appeared to have a lower risk of perinatal death. This does not appear to be an artefact related to the gestation at which the mother delivers, and was particularly associated with antepartum fetal deaths.
Commencement of antenatal care in the first trimester appeared to reduce the risk of all perinatal deaths, and for intrapartum asphyxia in particular. It is speculated that the mechanism may involve early detection and treatment of anaemia and syphilis.
Quality of perinatal care available in the area of residence, as measured by the presence of consultant obstetricians and a paediatric consultant unit, is shown to be significantly related to a reduction in deaths from intrapartum asphyxia, but it appeared not to be related to antepartum fetal deaths.  相似文献   
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