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81.
We reviewed 80 fractures of the calcaneus in 78 children through a 30-year period. The fractures were more equally distributed between the sexes than in adults. In contrast to adults, intraarticular fractures of the calcaneus in children constitute less than half, probably because a lower proportion of children sustain the fracture as a result of a fall. Associated injuries were mainly encountered by children who were traffic accident victims. It is disputable that the calcaneus in children is more resistant to fracture than in adults. The rarity of the fracture in children is more likely the result of less exposure to trauma leading to calcaneal fractures and also that the fracture is often overlooked. 相似文献
83.
84.
M J Seider K R Cleary P van Tassel R Alexanian S P Schantz A Frias L M Fuller 《Cancer》1991,67(4):929-932
Plasma cell granuloma is a rare, benign tumor most commonly found in the lungs in patients younger than 30 years. Although presentation has been reported at a number of other anatomic sites, this report is the first of plasma cell granuloma of the nasal cavity. The tumor was initially resected, but progression was seen at 1-month follow-up. Because further surgery to completely eradicate the tumor would have been extensive and disfiguring, 40-Gy external beam radiation was given in 20 fractions using a three-field wedge technique. Most recent clinical follow-up at 27 months showed local control. Surgery remains the treatment of choice for plasma cell granuloma when the disease can be completely resected. However, irradiation can also be effective in patients with recurrent or inoperable local disease. 相似文献
85.
Fourteen institutions performed 1,830 computed tomographic (CT) cerebral blood flow (CBF) examinations with 32% inhaled stable xenon. Respiratory rate delay greater than 10 seconds occurred in 3.6% of patients, with 83% of the delays lasting 10-15 seconds. There was no incident of prolonged respiratory difficulty. Headache (0.4%), seizures (0.2%), nausea and vomiting (0.2%), and change in neurologic status (0.1%) were uncommon, and there were no transient ischemic attacks. The CT CBF method with 32% inhaled stable xenon is thus associated with an acceptably low incidence of adverse reactions. 相似文献
86.
Between 1975 and 1984, the incidence of trichinosis in the United States (per million person years at risk) was 25 times greater for the Southeast Asian refugee population than for the general United States population. Cases in the southeast Asian refugees differed from those reported previously in the general population in geographic distribution and source of infected meat. Cambodians and Laotians accounted for over 90 per cent of the cases in the Southeast Asian refugees, but comprised less than 50 per cent of that total population. 相似文献
87.
F Gracia R Chavarria C Archbold M Larreategui L Castillo P Schantz W C Reeves 《The American journal of tropical medicine and hygiene》1990,42(1):67-69
Neurocysticercosis was not been reported from Panama until 1984. The first documented case was a 5-year-old male who lived with his family in a typical subsistence agriculture environment lacking all sanitary amenities. Pigs and other animals ranged freely in and around the home. This report concerns clinical studies of the patient and his family conducted 4 years later. The index case had neurologic sequelae and was strongly seropositive. A cerebral CT scan revealed multiple intracerebral calcifications. Three family members had antibody to Cysticercus detected by immunoblot assay. A 7-year-old seropositive sister had an intracerebral calcification detected by CT scan. All 6 family members had completely normal neurologic examinations. 相似文献
88.
Young adults with head and neck cancer express increased susceptibility to mutagen-induced chromosome damage 总被引:4,自引:0,他引:4
Factors that contribute to an increased prevalence of squamous cell carcinoma of the upper aerodigestive tract among young adults in the United States remain unknown. A potential etiologic factor may relate to a genetically controlled sensitivity to environmental carcinogens. This study, therefore, examined 20 young adult patients who had squamous cell carcinoma for mutagen-induced chromosome sensitivity. Lymphocytes from respective patients were cultured, exposed to the clastogen bleomycin, arrested during metaphase, and examined quantitatively for chromosome breakage. As compared with an age- and sex-matched control population, as well as a population of patients who had non-squamous cell carcinoma head and neck tumors, the young adult population with squamous cell carcinoma expressed a significantly increased number of bleomycin-induced chromosome breaks per cell. Furthermore, among the study patients, chromosome sensitivity was most apparent in the non-tobacco users and in patients less than 30 years of age. The expression of such chromosome fragility following mutagen exposure should be considered in epidemiologic studies that intend to define risk factors for development of head and neck cancer. 相似文献
89.
An international study on the serological differential diagnosis of human cystic and alveolar echinococcosis 总被引:1,自引:0,他引:1
B Gottstein P M Schantz T Todorov A G Saimot P Jacquier 《Bulletin of the World Health Organization》1986,64(1):101-105
An enzyme-linked immunosorbent assay (ELISA) for the serological differentiation of cystic (Echinococcus granulosus) and alveolar (E. multilocularis) echinococcosis in man has been evaluated. A discrimination rate of 95.1% was found for 82 sera from patients of geographically disparate endemic areas. This rate was essentially the same as that found for 57 Swiss patients, indicating that inter- and intraspecific strain differences do not influence the test results. The assay method is suitable for immunodiagnostic purposes as well as for seroepidemiological studies. 相似文献
90.
T Racz P G Sacks D L Taylor S P Schantz 《Archives of otolaryngology--head & neck surgery》1989,115(11):1322-1328
This study analyzed the capacity of both fresh unseparated peripheral blood lymphocytes and enriched natural killer (NK) cells to lyse head and neck cancer cell lines. In a 6-hour chromium-release assay, only Leu-19+ NK cells mediated significant lysis. Furthermore, cell lines established from poorly differentiated cancers were more sensitive to lysis than were cell lines established from well-differentiated cancers. Cell lines from well-differentiated cancers also less readily inhibited K562 lysis in a cold-target inhibition assay, were not recognized by NK cells in a monolayer absorption assay (unlike poorly differentiated cancers), and failed to form conjugates with NK cells in a single-cell assay. These results indicated that deficient killing of a well-differentiated cancer cell vs a poorly differentiated cancer cell is partly a function of diminished NK cell recognition and tumor binding necessary to initiate lysis. As in previous studies regarding the prognostic implication of quantitated measures of NK cell activity within head and neck cancer patients, the results support the biologic relevance of the NK cell as a defense mechanism against metastatic disease, especially in patients with poorly differentiated, low major histocompatibility complex class I-expressing head and neck cancers. 相似文献