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W Romaniuk 《Klinika oczna》1992,94(10):301-302
The methods of extracapsular cataract extraction generated some problems connected with postoperative opacification of the posterior capsule. The authors present clinical and experimental methods applied nowadays, intended to prevent these opacifications from forming.  相似文献   
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Previous studies have suggested that the optimum length for force generation of the parasternal intercostal (PS) muscles is well above functional residual capacity (FRC). We further explored this issue by examining the pressure-generating capacity of the PS muscles as a function of lung volume in anaesthetized dogs. Upper thoracic spinal cord stimulation (SCS) was used to electrically activate the PS muscles. Changes in airway pressure and parasternal resting length (LR) during airway occlusion were monitored over a wide range of lung volumes during SCS. To assess the effects of parasternal contraction alone, SCS was performed following phrenicotomy and section of the external intercostal, levator costae and triangularis sterni muscles. With increasing lung volume, there were progressive decrements in the capacity of the PS muscles to produce changes in airway pressure. The relationship between PS pressure generation and lung volume was similar to a previous comparable assessment of the external intercostal muscles. The PS muscles shortened during passive inflation and also shortened further (by > 20 % of LR) during SCS. Total shortening (passive plus active) increased progressively with increasing lung volume. Our results indicate that the capacity of the PS muscles to produce changes in airway pressure (a) falls progressively with increasing lung volume and (b) is similar to that of the external intercostal muscles. We speculate that the fall in PS pressure-generating capacity is related, in part, to progressive reductions in end-inspiratory length.  相似文献   
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BackgroundSquare knots can be difficult to construct in deep body cavities. The reversing half-hitch alternating post (RHAP) surgical knot has noninferior tensile strength and performance characteristics in deep body cavities. We compared the enterotomy repairs of novice learners in simulated deep body cavities using RHAP versus square knots after proficiency-based training.MethodsUndergraduate students were randomized to RHAP (n = 10) or square knot (n = 10) groups and trained to defined proficiency. They then performed hand-sewn enterotomy repairs of cadaveric porcine small bowels on flat surfaces and in simulated deep body cavities. We recorded time to knot-tying proficiency and to enterotomy repair, and burst pressures for the repair.ResultsMean time-to-proficiency in knot tying was equivalent between the RHAP and square knot groups (23 [standard deviation (SD) 3] v. 21 [SD 2] min, p = 0.33). Mean time for enterotomy repair in deep cavities was shorter for the RHAP group (16 [SD 2] min v. 21 [SD 1] min, p = 0.02). Mean burst pressures for enterotomy repair were equivalent on flat surfaces (128 [SD 41] v. 101 [SD 36] mm Hg, p = 0.31), and were significantly higher for the RHAP group in simulated deep body cavities (32 [SD 13] v. 105 [SD 37] mm Hg, p = 0.05).ConclusionThe RHAP knots appear to have superior performance versus square knots when tied in a deep body cavity by novice learners. Future work should focus on demonstrating the clinical relevance and broad utility of the RHAP knot in abdominal surgery. Both knot types should be taught to novice learners.  相似文献   
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An adverse intrauterine environment is associated with the future risk of obesity and type 2 diabetes. Changes in placental function may underpin the intrauterine origins of adult disease, but longitudinal studies linking placental function with childhood outcomes are rare. Here, we determined the abundance and phosphorylation of protein intermediates involved in insulin signaling, inflammation, cortisol metabolism, protein glycosylation, and mitochondrial biogenesis in placental villus samples from healthy mothers from the Healthy Start cohort. Using MANOVA, we tested the association between placental proteins and offspring adiposity (fat mass percentage) at birth (n = 109) and infancy (4–6 months, n = 104), and adiposity, skinfold thickness, triglycerides, and insulin in children (4–6 years, n = 66). Placental IGF-1 receptor protein was positively associated with serum triglycerides in children. GSK3β phosphorylation at serine 9, a readout of insulin and growth factor signaling, and the ratio of phosphorylated to total JNK2 were both positively associated with midthigh skinfold thickness in children. Moreover, peroxisome proliferator–activated receptor γ coactivator (PGC)-1α abundance was positively associated with insulin in children. In conclusion, placental insulin/IGF-1 signaling, PGC-1α, and inflammation pathways were positively associated with metabolic outcomes in 4- to 6-year-old children, identifying a novel link between placental function and long-term metabolic outcomes.  相似文献   
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Narcissistic personality disorder (NPD) and the manic and hypomanic episodes found in the bipolar disorders are characterized by grandiosity. It is possible that this shared grandiosity is a ‘homologous structure’ or reflects a superficial similarity between two disparate conditions. It is, however, possible that NPD and the bipolar disorders are more closely related than implied by their segregation into the separate superordinate categories of personality disorders and mood disorders. Whereas narcissism is considered to be a life-course, stable trait and the bipolar disorders are characterized by episodes of mania and depression, there is considerable research indicating that narcissism may be linked to mood instability (including depression) and bipolar disorder may have a pervasive personality component (i.e., hypomanic personality). Utilizing dimensional models of psychopathology, the current review examined the evidence linking narcissism and the bipolar disorders and suggests that considerable overlap may exist in the domains associated with reward-seeking, harm avoidance and social functioning.  相似文献   
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Symptoms of posttraumatic stress disorder (PTSD), psychosis, general psychopathology, role functioning, violence potential, and cognitive and emotional aspects of psychotic states were compared in three groups of veterans. Groups were defined on the basis of their DSM-IV diagnoses: Psychotic disorder and war-related PTSD, war-related PTSD without psychotic symptoms, and psychotic disorder without PTSD. Veterans with PTSD and a comorbid psychotic disorder showed significantly higher levels of positive symptoms of psychosis, general psychopathology, paranoia, and violent thoughts, feelings, and behaviors than the other two groups. These data show that patients with comorbid PTSD and psychotic disorder show levels of cognitive, emotional, and behavioral disturbance that far exceed the levels of disturbance seen in patients with PTSD without psychosis or in patients with psychotic disorder.  相似文献   
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PURPOSE: To present the results of PC IOLs transscleral fixation to the ciliary sulcus in six years follow-up. MATERIAL AND METHODS: 152 eyes in 3 groups: 15 eyes with primary fixations of PC IOLs, 92 eyes with secondary fixations of PC IOLs and 45 eyes with secondary fixations of PC IOLs combined with penetrating keratoplasty. RESULTS: Postoperative corrected visual acuity was 0.5 or better in 32.2% of cases, the most common complications in our material was CME (9.9%), lens tilt (4.6%) and increase of IOP (3.95%). CONCLUSION: Transscleral fixation of PC IOLs offers good visual outcome with relatively low rate of complications and is recommended in cases with inadequate posterior capsule support.  相似文献   
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