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71.
OBJECTIVE: Congenital heart defects with major aortopulmonary collateral arteries show marked variability in the size and distribution of native pulmonary arteries. We sought to classify the size and distribution of native pulmonary arteries and to determine their influence on surgical outcome. METHODS: Between 1989 and 2002, 164 patients underwent surgical intervention for congenital heart defects with major aortopulmonary collateral arteries (median age, 10 months). Three patterns of native pulmonary arteries were identified: intrapericardial native pulmonary arteries present (group I); confluent intrapulmonary native pulmonary arteries without intrapericardial native pulmonary arteries (group II); and nonconfluent intrapulmonary native pulmonary arteries (group III). Thirty-seven (23%) patients had single-stage and 76 (47%) patients had multistage complete repair. Thirty (18%) patients await septation, and 8 (5.0%) patients are not septatable. Follow-up is 98% complete (median follow-up, 5.8 years). RESULTS: In the 164 patients there were 15 (9.1%) early and 12 (7.3%) late deaths. Early mortality after complete repair was 4.4% (n = 5). Actuarial survival was 90% +/- 3% and 85% +/- 4% at 1 and 10 years, respectively. Actuarial freedom from surgical or catheter reintervention in septated patients was 77% +/- 4% and 45% +/- 8% at 1 and 10 years, respectively. On multivariate analysis, the morphology of the native pulmonary arteries was the only factor that influenced actuarial survival after complete repair (P =.04). Group III had the highest risk of death after septation (P =.008). Group II fared better than group III after the initial operation (P <.05). CONCLUSIONS: Current classifications of congenital heart defects with major aortopulmonary collateral arteries are based on the presence or absence of intrapericardial pulmonary arteries. We have identified a subgroup without intrapericardial native pulmonary arteries but with confluent intrapulmonary native pulmonary arteries. This group has a better outcome than those with nonconfluent intrapulmonary native pulmonary arteries.  相似文献   
72.
The introduction of potent antiretroviral drug combinations has transformed human immunodeficiency virus/acquired immunodeficiency disease syndrome (HIV/AIDS) from an intractable and rapidly fatal disease to a chronic manageable illness with prolonged life survival for many patients. This paper discusses the ophthalmic and medical histories of two young female patients who presented with 'atypical' optic neuropathy and toxoplasma gondii retinochoroiditis and were later found to be HIV infected. We discuss the need for increased vigilance in the ophthalmic community for suspecting HIV infection to allow optimal management of the ophthalmic and systemic manifestations of the disease spectrum associated with HIV/AIDS.  相似文献   
73.
AIM: Leukaemia inhibitory factor (LIF) is a pleotrophic cytokine expressed in a variety of cell types, and have shown to regulate stem cell proliferation, vascular genesis, inflammation, and immunity in various locations. Expression of LIF and its role in the cornea have not been studied previously. In this study, we examined the expression of LIF in the cornea. MATERIALS AND METHOD: Immunohistochemistry was performed using polyclonal LIF antibodies, and Avidin-Biotin ABC complex on cultured human corneal epithelium corneal fibroblasts and wild-type murine corneal epithelium. RESULTS: LIF was detected in the cytoplasm of murine corneal epithelium, cultured human corneal epithelium, and fibroblasts. The expression of LIF was mainly cytoplasmic. CONCLUSION: LIF is expressed in the corneal epithelium and fibroblasts. It may have an important role in the maintenance of homeostasis of the corneal epithelium and cornea stroma. Further studies are necessary to elucidate the role of LIF in the cornea.  相似文献   
74.
AIM: To design, develop and test a system for analysis of photic phenomena. METHOD: Extensive background research, patient interviews and theoretical studies led to development of a set of photographic images resembling photic phenomena experienced by patients. These photographic images were processed and digitally altered to create scales of severity for each photic phenomenon in which patients indicated their severity of symptoms by choice of image. The system was tested for stability and validity. RESULTS: The system showed excellent repeatability and reliability. Face, content, criterion and construct validity were all found to be acceptable. CONCLUSION: The photographic images of photic phenomena analyser is an acceptable, validated measure for the assessment of photic phenomena, in both pseudophakic patients and those with cataract.  相似文献   
75.
Dhillon AS  Kolch W 《Cancer cell》2004,5(4):303-304
The Raf/MEK/ERK pathway is a conserved signaling module controlling cell growth, proliferation, apoptosis, and differentiation. Constitutive activation of this pathway is involved in malignant transformation by several oncogenes, most notably, Ras. The recent discovery by Davies et al. of somatic mutations in the B-RAF gene in human tumors has generated enormous interest in how Raf kinases are regulated and how mutations in B-RAF lead to transformation. A recent study in Cell by Wan et al. reports the crystal structure of the B-Raf kinase domain, providing important new insights into these questions.  相似文献   
76.
Severe, chronic pulmonary hypertension in childhood is uncommon, difficult to treat, and carries a poor prognosis. Sildenafil (Viagra, Pfizer) has been used successfully in adults with pulmonary hypertension as monotherapy or in combination with inhaled prostacyclin. Here we report on its use in three children.  相似文献   
77.
78.
PURPOSE: To determine whether patients with age-related macular degeneration (ARMD) benefit from cataract surgery and to assess the risk of progression of preexisting maculopathy 4 and 12 months postoperatively. SETTING: Princess Alexandra Eye Pavilion, Royal Infirmary of Edinburgh, Edinburgh, Scotland. METHODS: Two groups of patients were evaluated prospectively. The study group comprised patients with ARMD scheduled to have cataract surgery (n = 40). The control group comprised patients with ARMD not having cataract surgery (n = 43). Patients were assessed at baseline (preoperatively) and 4 and 12 months postoperatively. Assessment included visual function tests and quality of life (QoL) measures. The mean values for each item tested were obtained for each group at each visit, and comparisons between visits were done using the Wilcoxon signed rank test. RESULTS: There were significant benefits of cataract surgery in terms of visual function and QoL measures at 4 and 12 months. There was no increased risk of progression of maculopathy in the study group. There were no significant differences in the items tested in the control group. CONCLUSIONS: One year postoperatively, QoL benefits were maintained in the study group and there was no increased risk of progression of maculopathy in patients with mild and moderate degrees of ARMD. Larger numbers of patients must be assessed prospectively for longer periods to determine the relative risk of progression of different stages of ARMD after cataract surgery.  相似文献   
79.
Eaton MP  Dhillon AK 《Anesthesia and analgesia》2003,97(4):1074-7, table of contents
Pressure infusion devices are often used to administer fluids in the operating room, but they may rarely be associated with serious venous air embolism. We studied the performance of the Level 1 and the Ranger Pressure Infusor in the laboratory. The Ranger delivered less air and delivered fluid faster than the Level 1 but did not warm fluid or blood as well. Although the Ranger device may be safer in terms of the risk of air embolism, its inferior warming performance shows that the optimal pressure infusion device has yet to be manufactured. IMPLICATIONS: Pressure infusion devices are widely used to treat patients with large-volume blood loss. The use of these devices may subject patients to the risk of venous air embolism. Our study found the new Ranger device to be superior to the widely used Level 1 in air elimination.  相似文献   
80.
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