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61.
Cardiac performance was evaluated in 12 infants with isolated total anomalous pulmonary venous return. Four had significant pulmonary venous obstruction and severe pulmonary hypertension (group A). Eight had no obvious venous obstruction, and the pulmonary pressures were lower (group B). In all subjects, right ventricular end-diastolic volume was increased (197% of predicted normal) and its ejection fraction was normal. Left ventricular volume was, generally speaking, still in the normal range (87% of predicted normal); however, its ejection fraction was reduced (0.57 vs normal of 0.73) and left ventricular output was low (3.08 L/min/m2 vs normal of 3.98). Left atrial volume was consistently small (53% of predicted normal) with an appendage of normal size. The infants in group A had smaller chamber volumes/m2 BSA than those in group B. Left atrial function was abnormal, characterized by reduced reservoir function and a greater role as "conduit" from right atrium to left ventricle. Left atrial size was not found to be critical in the surgical repair of TAPVR. Cardiac function is restored to normal following surgery.  相似文献   
62.
A representative sample of 310 long-term unemployed in Norway was followed for 2 years with clinical examinations and the AUDIT questionnaire. 30% of the men and 8% of the women scored over the cut-off point for an alcohol use disorder. This gives a probable prevalence of 16%. The test predicted return to employment in this sample. The AUDIT answers were also used as a basis for dividing into three groups: 'normal', 'hazardous' and 'harmful'. At 2 year follow-up, 27% had changed group, 32 respondents to the worse and 24 to the better. This 'unstable' group was characterized by weaker social network and more frequent drinking. The AUDIT was judged as a useful instrument both in a routine health examination and as an epidemiological tool.  相似文献   
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At the University College Hospital, Ibadan, Nigeria, in a 22-month period from January 1975 to September 1976, nine splenectomies were electively performed for unruptured spleens. The diagnoses were either tropical splenomegaly syndrome (when no obvious cause was found to be responsible for, or associated with, the splenomegaly) or splenic abscess in various stages of formation. The weights of the spleens removed ranged from 160 g in a 15-year-old girl to 5080 g in a 39-year-old male. One death due to uncontrollable bleeding from the splenic bed occurred. Histology of the spleens after removal showed lymphosarcoma in one, non-specific changes in another, and thickened fibrous capsule, perisplenitis, haemorrhagic infarcts, pockets of chocolate-coloured fluid and inflammatory processes in various stages in the other seven. In the tropics, enlarged spleens with no obvious cause or associated condition are often best treated by splenectomy for histological diagnosis, definitive treatment and the prevention of rupture caused by minor trauma. There are, as yet, no convincing data which show that splenectomy in the tropics causes a significant diminution of immunity to malaria (or other diseases) and it does not, therefore, predispose to the development of cerebral malaria.  相似文献   
65.
On the 2nd postflight day the activity of neutral protamine peptide hydrolase of different compartments of the rat brain did not differ from the control level. With respect to the protein and RNA content and concentration motoneurons of anterior horns of the spinal cord and their glial-cells-satellites of rats exposed to the ground-based synchronous experiment did not differ from those of vivarium controls, except cells of the supraoptic nucleus. That was found on the 2nd and 27th postflight days. On the 2nd postflight day the protein and RNA concentration in neurons decreased and the protein concentration and content in gliocytes lowered; the RNA concentration and content in Purkinje cells of the cerebellum became reduced. On the 27th postflight day the RNA concentration in neurons of the supraoptic nucleus remained diminished whereas the protein content increased; in spinal motoneurons the protein concentration decreased and in adjacent gliocytes the protein concentration and content lowered. All the above changes made no more than 15% of the control values.  相似文献   
66.
The time development of the association of the lac repressor to the operator is considered in a model where the repressor is allowed to bind unspecifically to DNA and move along the DNA chain in a one-dimensional diffusion. The coupling to the three-dimensional diffusion outside the chain is introduced by letting the repressor associate and dissociate from the chain until it is finally bound to the operator. All distance correlations along the chain are included. The mean time of association is calculated and through a comparison with experimental data the molecular parameters are determined. The one-dimensional diffusion constant is found to be of the order of 10(-9) cm(2)s(-1). The model is sufficiently general to be applicable to other similar systems.  相似文献   
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As part of an extensive cross-sectional survey of Norwegian physicians carried out in 1993 the 1,158 retired members of The Norwegian Medical Association were sent a questionnaire about their social situation, work activity, health and well-being. The response rate was 76%. 62% of the respondents were 75 years or older, and 13% were women. 44% were still active, doing clinical, research, or consultation work. The most prevalent complaint was lower back trouble, followed by arthrosis and hypertension. It was relatively common to prescribe one's own drugs. 6-8% of physicians under 75 years and 28% of those over 84 years needed practical help, but the great majority rated their life quality as good or excellent.  相似文献   
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Prevailing fibrin-formation in the pleural cavity entails hypoactivity of trypsin-like proteinases and a high inhibitory potential in the serum and pleural exudate. Streptokinase preparations appeared an effective means of pharmacological pulmonary decortication in patients with high pleural levels of plasminogen. The authors obtained higher efficacy of conservative therapy for pyothorax when they used a specially designed technique of intrapleural administration of streptokinase-activated fresh frozen plasma of the same group. The outcomes of the disease were also improved noticeably.  相似文献   
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