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Refusal to eat by the elderly, and subsequent malnutrition, occurs in both institutional and community settings. Causes include physiologic changes associated with aging, mental disorders such as dementia and depression, and medical, social, and environmental factors. Treatment approaches call for management of these causes while considering the roles that medicine, ethics, and culture play in the process. 相似文献
43.
Two patients with sinus tracts from retained T-fasteners following PEG tube placement are reported. Both patients had the PEG tubes subsequently removed and presented with purulent discharge and granulations near well-healed gastrostomy sites. The management of this complication and a possible method of prevention are discussed. 相似文献
44.
PURPOSE: To report the clinicopathologic features of intraocular osseous production in association with proliferative vitreoretinopathy. METHOD: The clinical and histopathologic features of two patients with proliferative vitreoretinopathy and intraocular bone formation are reviewed. RESULTS: Preretinal osseous tissue incorporated in the proliferative vitreoretinopathy was surgically removed in one patient, and osseous tissue was present in the proliferative vitreoretinopathy in the enucleated eye of the other patient. CONCLUSIONS: Bone formation, presumably from metaplastic retinal pigment epithelium, may be present in proliferative vitreoretinopathy tissue. The intraocular bone is present internal rather than external to the neurosensory retina. 相似文献
45.
EL Palacios-Prü L Miranda-Contreras RV Mendoza-Brice?o JR Lozano-Hernández 《Canadian Metallurgical Quarterly》1998,18(2):267-284
1. Information obtained during the last decade has demonstrated that hypothalamic neurons release a wide variety of neuroactive substances, such as neurotransmitters, mostly monoamines and amino acids, and neuromodulators such as the peptides vasopressin (AVP) and oxytocin (OXT) and hypophysial releasing hormones. 2. Synapse formation between hypothalamic neurons was followed at different times within a given nucleus and among different nuclei during development of the mouse hypothalamus. 3. The amounts of various neurotransmitters and hormones were determined at various stages of development. 4. A correlation is presented of the biochemical and ultrastructural features and their functional implications during maturation. 相似文献
46.
RF Bury AR Cowen AG Davies EL Baker P Hawkridge AJ Bruijns H Reitsma 《Canadian Metallurgical Quarterly》1998,53(12):923-928
This paper presents a brief technical evaluation and first review of clinical experiences with an experimental direct digital X-ray image detector designed to support both dynamic and snap-shot imaging. Derivatives of this type of image detector can potentially fulfil the majority of the fluoroscopic and radiographic imaging requirements of clinical radiology departments, and initial results suggest that imaging systems using the new technology will provide a high quality dose-efficient solution to the search for a universal digital X-ray image detector. 相似文献
47.
H Nagahara AM Vocero-Akbani EL Snyder A Ho DG Latham NA Lissy M Becker-Hapak SA Ezhevsky SF Dowdy 《Canadian Metallurgical Quarterly》1998,4(12):1449-1452
Human procathepsin L has been expressed in E. coli in the form of inclusion bodies. The recombinant protein was isolated, refolded and processed at pH 5.5 by the addition of dextran sulfate which increased the overall yield of cathepsin L almost 10-fold. After the auto-activation of the 38 kDa procathepsin L at least three processing sites were determined by N-terminal amino acid sequencing. After replacing the Ala205 residue by glutamic acid, cathepsin B-like specificity was introduced into cathepsin L. This mutation resulted in a 15-fold increased activity toward the substrate Z-Arg-Arg-AMC and in a 29-fold decreased activity toward Z-Phe-Arg-AMC. Residue 205 is thereby confirmed experimentally to be critical for the specificity of cathepsins B and L. 相似文献
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BACKGROUND: Bilateral tubal pregnancies are rare and are usually confirmed simultaneously during the same operation. We report a case in which the right salpingectomy was performed seven weeks before the left salpingectomy. When the right salpingectomy was done, the left uterine tube appeared entirely normal. CASE: A 38-year-old woman underwent laparoscopic surgery for suspected right tubal pregnancy. A right tubal pregnancy was found to have partially aborted into the peritoneal cavity. The left uterine tube was carefully inspected and appeared normal. Histopathology of the right tube showed products of conception and chorionic tissue. Seven weeks after surgery, the woman presented in hemorrhagic shock necessitating emergency laparotomy and left salpingectomy. Histopathology of the left tube confirmed the presence of chronic tissue. The patient did not have coitus between the two salpingectomies. CONCLUSION: The explanation of the presentation is uncertain. However, this case underscores the importance of careful follow-up of patients after laparoscopic surgery for ectopic pregnancies. 相似文献
50.