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41.
Seethalakshmi Viswanathan Naveen Chawla Anil D’Cruz Shubhada V. Kane 《Head and neck pathology》2007,1(2):169-172
Histoplasmosis is a rarely reported deep mycotic infection in the Indian context. Oral or oropharyngeal manifestation can
occur as an isolated symptom or as part of a disseminated process associated with immunosuppression especially with HIV and
diabetes. Five cases of head and neck histoplasmosis accrued over 6 years in a tertiary referral cancer institute were reviewed.
All these patients presented clinically as cancer. In three patients, the marked pseudoepitheliomatous hyperplasia led to
a mistaken biopsy diagnosis of malignancy following which definitive surgical treatment was performed. The subsequent excision
revealed typical features of histoplasmosis. Isolated oral presentation of histoplasmosis can mimic malignancy both clinically
as well as pathologically, leading to potentially disastrous consequences. A high index of suspicion in those with overt or
hidden immunosuppression and a deep wedge biopsy to demonstrate the organisms in the subepithelial tissue is recommended.
This work has been presented in the “Slide seminar on Infections and Infestations” in the IAP-ID pre conference CME in APCON
2006. 相似文献
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Dave H Lee Deborah Wenkert Michael P Whyte Michael T Trese Oscar A Cruz 《Journal of AAPOS》2003,7(1):75-77
Isteoporosis-pseudoglioma syndrome (OPPG) is a rare heritable entity that features severe osteoporosis and many variable ophthalmic findings leading to congenital or juvenile blindness. These include microphthalmos, cataracts, bilateral pseudogliomatous retinal detachments, and phthisis bulbi. OPPG is usually not suspected until fractures occur, frequently after seemingly minor trauma. We report the ophthalmic findings of an infant girl with OPPG. 相似文献
44.
Gunnar Rølla Bjørn Øsard Roberval de Almeida Cruz 《Journal of clinical periodontology》1993,20(2):105-108
Abstract Prevention of caries in exposed root surfaces constitutes an important clinical problem. It is thus important that clinicians involved with periodontology have an insight into fluoride prophylaxis. The understanding of the cariostatic mechanism of fluoride has improved during recent years. The aim of the present review is to give a short account of the present concept. Calcium fluoride appears to be the only product which is formed on enamel, dentin or cementum during brief topical treatments with fluoride or use of toothpaste containing fluoride. This calcium fluoride is stable in the oral environment: this is contrary to what was believed until recently. The calcium fluoride constitutes a pH-dependant reservoir of fluoride which releases fluoride when pH drops. The practical consequences of this concept is discussed. 相似文献
45.
Consequences of the North American Free Trade Agreement for health services: a perspective from Mexico. 总被引:1,自引:0,他引:1 下载免费PDF全文
J Frenk O Gmez-Dants C Cruz F Chacn P Hernndez P Freeman 《American journal of public health》1994,84(10):1591-1597
OBJECTIVES. The purposes of the study were to assess the potential impact of the North American Free Trade Agreement (NAFTA) on medical care in Mexico and to identify internal measures Mexico could take to increase the benefits and minimize the risks of free trade. METHODS. The dual nature of the health sector is examined; the Mexican, Canadian, and US health care systems are compared; and modes and consequences of international exchange of health services are analyzed. RESULTS. Four issues require immediate attention: accreditation of health care facilities, licensing and certification of professionals, technology assessment, and financial equity. CONCLUSIONS. NAFTA offers opportunities for positive developments in Mexico, provided risks can be anticipated and preventive measures can be taken to avoid negative impacts on the health system. Medical services, like other elements of the Mexican economy, must be modernized to respond to the demands of global competition. The Mexican National Academy of Medicine has recommended to the Mexican government (1) internal strengthening of the Mexican health care system to improve its ability to respond to the new conditions created by NAFTA and (2) a gradual process to facilitate equitable and mutually beneficial interactions among the three countries. 相似文献
46.
Rupture of an intra-aortic balloon counterpulsator (IABCP) demands immediate removal. We report a case of thrombus formation within a Datascope IABCP secondary to IABCP rupture, necessitating surgical exploration for removal. There is a disturbing pattern of balloon ruptures with this type of IABCP. 相似文献
47.
Transmitter release from presynaptic terminals of electric organ: inhibition by the calcium channel antagonist omega Conus toxin 总被引:3,自引:0,他引:3
R E Yeager D Yoshikami J Rivier L J Cruz G P Miljanich 《The Journal of neuroscience》1987,7(8):2390-2396
Cholinergic synaptosomes from electroplax of the ray Ommata discopyge release both ATP and ACh when depolarized with high K+ concentration in the presence of Ca2+. Others have shown that the ATP and ACh are released in the molar ratio found in isolated synaptic vesicles. Thus, it is assumed that the release of ATP reflects exocytosis of synaptic vesicles, and that transmitter release can be indirectly monitored by assaying ATP release. We present further evidence for this assumption and examine the effects of presynaptic neurotoxins on this ATP release. As expected for transmitter release, we find that depolarization-evoked ATP release is supported by Sr2+ and Ba2+ and is inhibited by the Ca channel antagonists Co2+ and Mn2+. Likewise, the presynaptic toxins omega-CmTX and omega-CgTX, omega peptides from the venom of the marine snails Conus magus and Conus geographus, respectively, inhibit 80% of the depolarization-evoked ATP release. Half-maximal inhibition of ATP release occurs with approximately 0.5 microM of either toxin. The toxins' effects are reversible, and when toxin is washed away, the time dependence of recovery of release is approximately first order and half complete within 40 min with omega-CmTX and 15 min with omega-CgTX. The Ca2+ ionophore A23187 induces Ca2+-dependent ATP release from resting synaptosomes. As would be expected of a Ca channel antagonist, omega-CmTX does not affect this ionophore-induced release. Leptinotarsin-d (LPTd), a putative Ca channel agonist from the Colorado potato beetle, evokes Ca2+-dependent ATP release from resting synaptosomes. omega-CmTX does not block LPTd-evoked release of ATP, which suggests that omega-CmTX and LPTd act at different sites.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
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PURPOSE: To ascertain the prevalence of uveitis in a population of pediatric patients with inflammatory bowel disease without ocular symptoms. METHODS: We prospectively evaluated all young people who came to the pediatric gastroenterology clinic with endoscopically proven inflammatory bowel disease between March 1994 and June 1995. All the patients were examined for evidence of ocular manifestations of inflammatory bowel disease. The examination consisted of slit-lamp examination, tonometry, and indirect ophthalmoscopy. None of the patients had visual or ocular symptoms. Eighteen patients had Crohn's disease and 14 had ulcerative colitis. RESULTS: Of the 32 patients evaluated, four (12.5%) had evidence of asymptomatic ocular inflammation, defined as anterior chamber cell and flare. All patients with ocular inflammation were male. Three of these four male patients had Crohn's disease; the other had ulcerative colitis. Five patients had posterior subcapsular cataract, one had esotropia and amblyopia, and one had unilateral high myopia. CONCLUSIONS: The prevalence of asymptomatic uveitis in our population of young people with inflammatory bowel disease was 12.5%. These findings suggest the need for a screening ophthalmologic examination to rule out occult eye disease in young people with inflammatory bowel disease. 相似文献