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111.
A strain of Aspergillus fumigatus has been isolated from sediments of a mussel bed. When cultured in hyper saline conditions (with sea-water), it produces a cytotoxic and immunosuppressive toxin, gliotoxin, which is excreted in an exudate. In order to know if this toxin could represent a risk for shellfish consumers, an experiment of bioaccumulation of gliotoxin in mussel has been carried out. After 6 days of contamination, toxin was accumulated in the meat of the mussels, at a level up to 2.9 microg/mg of extract weight, with a mode of contamination different to the classical digestive process described for a majority of marine toxins, but similar to the contamination mode of domoic acid. 相似文献
112.
Marc Hermier Norbert Nighoghossian Laurent Derex Patrice Adeleine Marlène Wiart Yves Berthezène Fran?ois Cotton Jean-Baptiste Pialat Pascal Dardel Jér?me Honnorat Paul Trouillas Jean-Claude Froment 《Journal of cerebral blood flow and metabolism》2003,23(11):1362-1370
Prediction of hemorrhagic transformation (HT) in patients treated by intravenous recombinant tissue-type plasminogen activator (rt-PA) is a challenging issue in acute stroke management. HT may be correlated with severe hypoperfusion. Signal changes may be observed at susceptibility-weighted magnetic resonance imaging (MRI) within large perfusion defects. A signal drop within cerebral veins at T2*-weighted gradient-echo MRI may be expected in severe ischemia, and may indicate subsequent risk of HT. The authors prospectively searched for an abnormal visibility of transcerebral veins (AVV) within the ischemic area in patients with hemispheric ischemic stroke, before they were treated with intravenous rt-PA therapy. Any correlation between AVV and baseline clinical or MRI findings, or further HT, was noted. An AVV was present in 23 of 49 patients (obvious, n = 8; moderate, n = 15), and was supported by severe hemodynamic changes at baseline MRI. The AVV was correlated with the occurrence of parenchymal hematoma type 2 at computed tomography during the first week (r = 0.44, P = 0.002). Five of six type 2 parenchymal hematomas occurred in association with obvious AVV. At multiple regression analysis, two baseline MRI factors had an independent predictive value for HT risk during the first week: the AVV and the cerebral blood volume ratio (Nagelkerke R2 = 0.48). 相似文献
113.
114.
Histologic and immunohistochemical properties of 53 medulloblastomas were analyzed with regard to clinical features and survival rate. No correlation was found between survival rate and histologic features of the tumor, such as desmoplastic reaction, number of mitoses, hemorrhages, necrosis, endothelial proliferation, glomerular arrangement, calcifications, rosettes, or oligodendroglial cells. However 82% of the patients with positive glial fibrillary acidic protein (GFAP) staining in numerous tumor cells survived more than 5 years; only 30% survived that long if their tumor cells were GFAP negative (P = 0.0093). This significant difference was not related to the mode of therapeutic protocol used. The authors suggest that GFAP staining may be a useful prognostic tool in medulloblastoma. 相似文献
115.
D L Cohen L B McCullough R W Kessel A Y Apostolides E R Alden K J Heiderich 《Journal of medical education》1987,62(10):789-798
When medical students become involved in patient care, concerns are raised that have ethical and possibly legal implications. In order to determine compliance with the guidelines of the U.S. government and the Joint Committee on Accreditation of Hospitals pertaining to informed consent, the authors conducted a study of hospital administrators, medical school department chairpersons, and medical school deans (with response rates ranging from 82.3 to 95.1 percent) concerning policies on student involvement in patient care. The results show that only 37.5 percent of all responding teaching hospitals specifically informed patients that students would be involved in care. Only 51 percent of the responding medical schools that specifically gave their students instruction or guidance on initial patient interaction as a matter of policy insisted that their students introduce themselves as students and clarify their role in patient care. The authors conclude that medical educators' compliance with the ethical requirements of informed consent is incomplete. 相似文献
116.
117.
G W Diamond J Kaufman A L Belman L Cohen H J Cohen A Rubinstein 《Archives of clinical neuropsychology》1987,2(3):245-256
The cognitive status of 12 clinically stable children with congenital HIV infection, nine of whom were neurologically impaired, age three to nine years, was assessed using the Kaufman ABC test. Seven of the children had ARC; five were diagnosed as having AIDS. The same children were evaluated by standard neurologic examinations with Characterization of tone and fine motor functioning. Two were diagnosed as being mildly retarded; six were borderline; and four tested as being of average intelligence. Visual-spatial perceptual based functioning was found to be more impaired than were abstract reasoning and verbally mediated skills in six (50%) of the patients. This pattern of impaired information processing was found irrespective of overall cognitive status. On neurological and physiatric examination abnormal developmental histories were obtained, or poor fine motor coordination, abnormal tone and gait, and impaired rapidly alternating movements were found in 9 of the 12 subjects. These findings suggest selective impairment in distinct areas of neurologic and neuropsychological functioning during stable phases of HIV infection in a select group of children. These patterns appear to persist over time. They differ from the clustering of impaired skills seen in children of comparable socio-cultural backgrounds without HIV infection. Similarities in functioning are noted between this subgroup of children with AIDS and ARC and comparable groups with cerebral palsy. 相似文献
118.
Identifying alcoholism in medical patients 总被引:1,自引:0,他引:1
119.
120.
H Bekri R Cohen E Varon F Madhi R Gire F Guillot C Delacourt 《Archives de pédiatrie》2007,14(3):239-243
It has been suggested that the incidence of childhood empyema have increased during the last years in France without clear explanation. Streptococcus pneumoniae is responsible for the vast majority of bacteriological documented cases. Potential prevention of pleural empyemas by the heptavalent pneumococcal conjugate vaccine is dependent on adequation between specific pneumococcal serogroups present in vaccine and those responsible for empyemas. MATERIAL AND METHODS: We retrospectively collected cases of pleural empyemas registered at the National Reference Center for pneumococci (December 2002 to February 2004). Thirty children, aged 4.1+/-3.3 (SD) years, were included. RESULTS: Ten specific serogroups were identified: 1, 3, 5, 6B, 7F, 9V, 14, 18C, 19A, and 23F. Serogroups 19A and 1 were the 2 dominant serogroups and represented 50% of cases. All children infected with serotype 19A were younger than 5 years, whereas serotype 1 was identified in 80% of empyemas in children older than 5 years. Among the 30 patients enrolled, 20 (69%) were infected with serotypes not included in the conjugate vaccine. CONCLUSION: These results thus limit the potential impact of the heptavalent pneumococcal conjugate vaccine on the frequency of pleural empyemas in children. 相似文献