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11.
OBJECTIVE: To compare structural and functional outcomes and efficiency of diode laser photocoagulation for retinopathy of prematurity (ROP) when delivered in a pulsed mode versus a near-continuous mode. METHODS: A retrospective study was conducted of 138 patients who underwent diode laser photocoagulation for threshold ROP using either pulsed or near-continuous delivery. Laser-related complications and structural and functional outcomes were analyzed. Prospectively, time efficiency and total energy used were evaluated in nine infants with bilateral symmetric high-risk prethreshold ROP in which one eye of each infant was randomized to pulsed and the fellow eye to near-continuous delivery. RESULTS: There was no significant difference between groups with regards to prevalence of posterior disease (Zone 1 or posterior Zone 2) (p = 0.11), postoperative vitreous haze (p = 0.60), postoperative complications (p = 0.38), retinal detachment (p = 0.90), strabismus (p = 0.73), amblyopia (p = 0.69), or refractive error (p = 0.95). Mean time for treatment was 23 minutes using pulsed delivery versus 14 minutes per eye with near-continuous delivery (p < 0.001). The mean total power used per eye with pulsed mode delivery was 1.5 x 10(5) W versus 1.1 x 10(5) W with near-continuous delivery (p = 0.015). CONCLUSIONS: No differences in complications, functional outcome, or structural outcome were found between using pulsed mode and near-continuous mode diode laser delivery for high-risk ROP. Near-continuous laser delivery, in our hands, was more time-efficient and used less total power.  相似文献   
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Thirteen young Egyptian males with initial low plasma retinol level were divided into three groups and received single oral vitamin A dose of 200,000 IU, or carotene supplement in the form of boiled spinach leaves, providing roughly 617 RE/day or carrots providing 394 RE/day. The three supplements were equally effective, when the plasma retinol level was measured 40 days later. On a price basis, the vitamin A capsules and the carrots were much cheaper than the spinach supplement.  相似文献   
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Neonatal septicaemia (NNS) is a major cause of neonatal morbidity and mortality. Neonatal septicaemia was studied to determine the incidence, common bacterial aetiology and antibiotic susceptibility in Qatif Central Hospital, Saudi Arabia. Of 1,797 babies admitted into the unit over a 3 year period, 144 (8.0%) had documented neonatal septicaemia consisting of 94 (65%) late onset and 50 (35%) early onset septicaemia. The incidence was 8.2/1000 of the total live births in the hospital.

Gram negative bacteria were encountered in 66.2%, gram positive bacteria in 29.2% and Candida albicans in 4.4% of the case. Klebsiella spp., E. coli, and Pseudomonas accounted for 81.8 % of the gram negative while Staphylococcus epidermidis, Staphylococcus aureus and group B Beta haemolytic Streptococcus accounted for 73.9% of the gram positive bacteria.

Most of Gram negative bacteria had a high sensitivity to Aminoglycosides and third generation Cephalosporins. Coagulase negative staphylococci were frequently resistant to most antibiotics but always sensitive to Vancomycin. The overall mortality rate was 18.7%.  相似文献   
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Cutaneous malignant melanoma (CMM) is a life-threatening cancer that can have a poor prognosis with high metastatic potential. Its incidence is rapidly increasing worldwide. Its molecular alterations involve multiple pathways, including those related to p53. Since 1981, more than 380 papers containing the terms 'p53 and melanoma' as key words in the Abstract have been published in the literature. However, in spite of these extensive investigations, a review of p53 and associated genes in CMM is still lacking. To remedy this issue, this review seeks to provide a brief overview of p53 and discuss the genes targeted along its related pathways.  相似文献   
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Backscatter imaging is useful for inspecting structures that are accessible only from one side. However, indications provided by scattered radiation are typically weak, convoluted and difficult to interpret. This paper explores the use of the coded aperture technique to detect flaws using gamma-ray backscatter imaging. The viability of this approach is demonstrated with indications obtained from Monte Carlo simulations of radiation scattering measurements. The results show that, with a 2 mm wide beam of 137Cs photons, flaws as small as 1.5 mm in width can be detected using this technique. Indications of changes in flaw size, location, multiplicity and density were also observable. In addition, it is possible to quantify, from the decoded indications, the flaw location and its size.  相似文献   
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Hodgkin's lymphoma rarely involves the thyroid gland. We report the clinical and pathologic features of five cases of Hodgkin's lymphoma that presented as thyroid lesions. All five patients were females, aged 29-59 years. Three patients had a history of chronic thyroiditis and hypothyroidism and two were euthyroid. One patient had a remote history of Hodgkin's lymphoma. Imaging studies showed a 'cold' nodule (three cases) or a diffusely enlarged thyroid gland, resembling goiter or fibrosclerosing thyroiditis (two cases). Thyroid fine-needle aspiration was performed before thyroidectomy in all cases; three of these cases contained some atypical cells, raising the possibility of Hodgkin's lymphoma. Histologically, all cases were classical Hodgkin's lymphoma, nodular sclerosis subtype. The four patients with primary thyroid lymphoma had Stage IIE disease. All patients were treated with surgical excision and chemotherapy, with or without radiation therapy, and were alive after 2 months to 7 years of follow-up. A review of the English literature between 1962 and 2005 revealed 16 cases of thyroid Hodgkin's lymphoma, with a female preponderance and generally favorable outcome similar to the cases in our series. Hodgkin's lymphoma of the thyroid is rare and can mimic a primary thyroid epithelial tumor or thyroiditis clinically. Histologic diagnosis may be difficult due to marked fibrosis. Hodgkin's lymphoma should be considered in the differential diagnosis of thyroid neoplasms.  相似文献   
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The aims of this paper are to provide a brief overview of the types of education and training as well as a framework for co-occurring disorders courses at foundation and advanced levels. Mental health nurses encounter substance abuse problems as part of their workload and should be prepared adequately to work with individuals with the co-existence of mental health and substance abuse. However, co-occurring disorders are not often picked up by substance abuse or mental health services, indicating a need for improvement in ongoing professional development. The targeted audience for education and training in core competencies should be staff working in community mental health teams, inpatient services, assertive outreach teams, early intervention teams, crisis resolution teams, primary care, mental health services for older people, independent mental health projects, accommodation services, day care services, statutory drug and alcohol services, independent drug and alcohol service providers, and those working in hostel accommodations, housing, prison health care probation, and others in the criminal justice system. The theoretical and skills-based training will need to adopt a two-tiered approach as individuals working within mental health services will by definition need a higher emphasis on training around substance misuse and vice versa for individuals working in substance misuse services. One of the agenda items for interagency training is to challenge negative attitudes and prejudices around both mental health problems and substance misuse.  相似文献   
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