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91.
We report a case of disseminated Scedosporium apiospermum infection in a neutropenic patient with acute myeloid leukemia. Due to progression of the mycosis after 7 days of amphotericin B lipid complex therapy and to high susceptibility of the mold to voriconazole in vitro, the patient was treated with intravenous voriconazole. After a few days of therapy, fever disappeared and skin lesions improved. However, the patient died after 1 month due to intestinal bleeding. Despite a negative outcome, this case seems to indicate a promising role for voriconazole in the treatment of S. apiospermum infections.  相似文献   
92.
Dehydroepiandrosterone (DHEA) exerts opposite effects on the growth of mammary carcinoma. A stimulatory effect is observed in absence of estrogens, due to interaction of DHEA metabolite(s) with the estrogen receptor (ER); by contrast, in presence of estrogens DHEA inhibits tumor growth. The mechanism underlying the latter DHEA effect, which might be related to activation of the androgen receptor (AR), is poorly understood. Focusing on this point, we measured over a 20 days period the areas of DMBA-induced mammary tumors in rats given DHEA and/or the anti-androgen flutamide (FLU). Results show that DHEA inhibitory effect on the growth of mammary carcinoma is no longer observed when the ARs are blocked by FLU. Data are consistent with an involvement of ARs in the inhibitory effect of DHEA.  相似文献   
93.
The data are preliminary findings in order to study the possible pollution of fresh olive oil with Class I Pesticides, often misused by olive farmers, and it's effect on children's health. The oil produced from the olives of 8 farms in a small town of Southern Italy was collected at the mill in 1992, with no previous notice to the farmers, and was analyzed by Head Space Gas Chromatographic technique. The research for organophosphates and chlorinated pesticides was negative. The Kreis test excluded oil rancidity and the index of refraction confirmed the oils being fresh olive oil. The fact that the oil samples resulted free of pesticide residuals, however, might be explained by the unusual season weather not favourable to the olive parasites and the consequent reduced amounts of pesticides used by the farmers. The work will be repeated in 1993 and completed by a dietary semiquantitative questionnaire and epidemiologic evaluations on the children's health.  相似文献   
94.
In streptozocin (SZ)-induced diabetic mice, 200 islets, but not 50 islets, consistently restore euglycemia within 1 week of transplantation. To determine the minimum number of islets sufficient to maintain euglycemia in a diabetic mouse, we first transplanted 50 and 150 syngeneic islets simultaneously into the right (RK) and left kidney (LK), respectively, and then removed the LK 1 week post-transplantation. The remaining 50 islets maintained euglycemia in 8 of 11 mice with normal intravenous glucose tolerance tests (IVGTT). Protection of 50 islets for at least 7 days was necessary because removal of the 150 islets at 5 or 3 days resulted in a much lower incidence of persistent euglycemia. Similarly, 25 islets were capable of maintaining euglycemia in 2 of 9 mice once hyperglycemia was reversed by split-transplantation of 25 (RK) and 175 (LK) islets. To examine if 50-islet allografts survive longer than 200-islet allografts, we split-transplanted 50 DBA/2 islets in the RK and 150 islets of either B6 (syngeneic), DBA/2 (allogeneic), or C3H/He (third party allogeneic) mouse origin in the LK in 3 groups of diabetic C57BL/6 (B6) mice. The survival of 50 DBA/2 islets in each group after removal of the LK on day 7 was compared to that of 200 DBA/2 islets in control B6 mice. Maximum prolongation of allograft survival was obtained with 50 DBA/2 islets that were split-transplanted with syngeneic B6 islets. These results clearly demonstrate that 50 islets are sufficient to maintain normal glucose tolerance once euglycemia is induced by transplantation of a larger number (i.e., 200) of islets and that 50 islet allografts are much less immunogenic than 200-islet allografts.  相似文献   
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96.
Intimal hyperplasia (IH) is a leading cause of obstruction of vascular interventions, including arterial stents, bypass grafts and arteriovenous grafts and fistulae. Proposals to account for arterial stent-associated IH include wall damage, low wall shear stress (WSS), disturbed flow and, although not widely recognized, wall hypoxia. The common non-planarity of arterial geometry and flow, led us to develop a bare-metal, nitinol, self-expanding stent with three-dimensional helical-centreline geometry. This was deployed in one common carotid artery of healthy pigs, with a straight-centreline, but otherwise identical (conventional) stent deployed contralaterally. Both stent types deformed the arteries, but the helical-centreline device additionally deformed them helically and caused swirling of intraluminal flow. At sacrifice, one month post stent deployment, histology revealed significantly less IH in the helical-centreline than straight-centreline stented vessels. Medial cross-sectional area was not significantly different in helical-centreline than straight-centreline stented vessels. By contrast, luminal cross-sectional area was significantly larger in helical-centreline than straight-centreline stented vessels. Mechanisms considered to account for those results include enhanced intraluminal WSS and enhanced intraluminal blood–vessel wall mass transport, including of oxygen, in the helical-centreline stented vessels. Consistent with the latter proposal, adventitial microvessel density was lower in the helical-centreline stented than straight-centreline stented vessels.  相似文献   
97.
Benign infantile familial convulsions is an autosomal dominant disorder characterized by nonfebrile seizures, with the first attack occurring at age 3-12 mo. It is one of the rare forms of epilepsy that are inherited as monogenic Mendelian traits, thus providing a powerful tool for mapping genes involved in epileptic syndromes. Paroxysmal choreoathetosis is an involuntary-movement disorder characterized by attacks that occur spontaneously or are induced by a variety of stimuli. Classification is still elusive, and the epileptic nature of this movement disorder has long been discussed and remains controversial. We have studied four families from northwestern France in which benign infantile convulsions was inherited as an autosomal dominant trait together with variably expressed paroxysmal choreoathetosis. The human genome was screened with microsatellite markers regularly spaced, and strong evidence of linkage for the disease gene was obtained in the pericentromeric region of chromosome 16, with a maximum two-point LOD score, for D16S3133, of 6.76 at a recombination fraction of 0. Critical recombinants narrowed the region of interest to a 10-cM interval around the centromere. Our study provides the first genetic evidence for a common basis of convulsive and choreoathetotic disorders and will help in the understanding and classification of paroxysmal neurological syndromes.  相似文献   
98.
A case of sclerosing epithelioid fibrosarcoma and its appearance on MRI is presented. The tumor showed a zonal architecture on MRI with a large central core of very low signal intensity and a peripheral rim of intermediate to high signal intensity on T1- and T2-weighted spin echo pulse sequences. The core showed decreased cellularity with dense collagen deposition on histologic examination, and the peripheral zone increased cellularity with increased nuclear atypia. The presence of a prominent region of very low signal intensity on T1- and T2- weighted images can be seen with neural tumors, giant cell tumor of the tendon sheath, aggressive fibromatosis, and, in rare instances, with soft tissue sarcomas rich in collagen.  相似文献   
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