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991.
Over the last few decades the there has been a huge increase in the incidence of oesophageal adenocarcinoma, surpassing that of any other solid tumour. Barrett's oesophagus is recognised as a pre-malignant cursor. Surveillance programmes have evolved to monitor Barrett's oesophagus, with the intention to detect early malignant transformation. Using photosensitive agents photodiagnosis is developing to detect this transformation before it is visible endoscopically to allow early treatment. Photodynamic therapy is a non-thermal endoscopic ablative technique, which incorporates the same photosensitive agents to treat Barrett's oesophagus as well as malignant disease. In this article we review the present status of photodiagnosis and photodynamic therapy in the management of Barrett's oesophagus and early oesophageal carcinoma. 相似文献
992.
993.
Raquel Carreira Ana Duarte Pedro Monteiro Maria Sancha Santos Ana Cristina Rego Catarina R Oliveira Lino M Gon?alves Luís A Providência 《Revista portuguesa de cardiologia》2004,23(11):1447-1455
Ischemia negatively affects mitochondrial function by inducing the mitochondrial permeability transition (MPT). The MPT is triggered by oxidative stress, which occurs in mitochondria during ischemia as a result of diminished antioxidant defenses and increased reactive oxygen species production. It causes mitochondrial dysfunction and can ultimately lead to cell death. Therefore, drugs able to minimize mitochondrial damage induced by ischemia may prove to be clinically effective. We analyzed the effect of carvedilol, a beta-blocker with antioxidant properties, on mitochondrial dysfunction. Carvedilol decreased levels of TBARS (thiobarbituric acid reactive substances), an indicator of oxidative stress, which is consistent with its antioxidant properties. Regarding cell death by apoptosis, although ischemia did increase caspase-8-like activity, there were no changes in caspase-3-like activity, which is activated downstream of caspase-8; this may indicate that the apoptotic cascade is not activated by 60 minutes of ischemia. We conclude that carvedilol protects ischemic mitochondria by preventing oxidative mitochondrial damage, and, by so doing, it may also inhibit the formation of the MPT pore. 相似文献
994.
Dr. Yen-Chun Lin MD Jiahn-Shing Lee MD Shiu-Chen Wu MD Ling-Yuh Kao MD Chia-Yun Li MD Ken-Kuo Lin MD 《Annals of Ophthalmology》2003,35(1):19-24
This study analyzed the feasibility of fitting keratoconus-affected corneas with nonkeratoconus rigid gas-permeable (RGP)
contact lenses. We retrospectively studied patients with a diagnosis of keratoconus in the past 10 years who were fitted successfully
with nonkeratoconus RGP lenses by the same physician. Results confirmed nonkeratoconus RGP lenses as the first-line correction
tool. Additionally, we found a simple equation to speed the choice of the base curves of the lenses.
The authors have stated that they do not have a significant financial interest or other relationship with any product manufacturer
or provider of services discussed in this article. 相似文献
995.
996.
Urinary tract infections (UTI) are one of the most common and serious infections among pediatric patients in the emergency department. Detection of UTI requires a systematic approach to urine testing and an understanding of the limitations to common screening tests. Proper culturing techniques are essential to the diagnosis. Accurate diagnosis and prompt treatment can reduce morbidity associated with UTIs. 相似文献
997.
J. Francisco Salomão Sérgio Cavalheiro Hamilton Matushita René D. Leibinger Antonio R. Bellas Elide Vanazzi Luiz A. M. de Souza Andréa G. Nardi 《Child's nervous system》2006,22(3):234-242
Background Cystic dysraphic lesions of the cervical and upper thoracic region are rare and only a few series have been published about the topic. These malformations can be divided into categories that include both myelocystoceles and the so-called cervical meningoceles or myelomeningoceles.Methods A retrospective study of 18 patients was conducted.Results In 17 patients a squamous or a cicatricial epithelium of variable thickness covered the dome of the lesions, while the base was covered with full-thickness skin. In one case the skin was entirely normal. Four patients displayed associated CNS malformations and three more had systemic congenital anomalies. All patients underwent surgical exploration and the length of time between birth and surgery ranged from 6 h to 9 months. The most frequent surgical finding, seen in 14 patients, was a stalk connecting the dorsal surface of the spinal cord to the cyst. In three patients the findings were consistent with myelocystocele. Only in one case was a true meningocele found. Hydrocephalus and Chiari II malformation were not as consistently associated as in myelomeningoceles. Neurological signs and symptoms were not so marked as in myelomeningoceles and were found in the follow-up of four patients. In two of them there was a non-progressive deficit, probably expressing an imperceptible involvement of the nervous system in the first year of life. The histopathological findings were of three types: neuroglial stalks, fibrovascular stalks and myelocystoceles.Conclusions Cystic dysraphisms of the cervical and upper thoracic region differ clinically and structurally from meningomyelocele and have a more favorable outcome. We believe that these malformations have not been properly labeled and propose a classification based on the structures found inside the cyst. 相似文献
998.
Jonas T. Johnson MD Editor John K. Niparko MD Editor-in-Chief Paul A. Levine MD Editor David W. Kennedy MD Editor Pete Weber MD Editor-in-Chief Randal S. Weber MD Editor Michael S. Benninger MD Past Editor in Chief Richard M. Rosenfeld MD MPH Editor in Chief Robert J. Ruben MD Editor in Chief Richard J.H. Smith MD Editor in Chief Robert Thayer Sataloff MD DMA Editor in Chief Neil Weir MA FRCS Editor Emeritus 《Otolaryngology--head and neck surgery》2006,135(6):829-830
999.
1000.