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41.
Studies of functional plasticity after pre- or perinatal brain damage can tell us whether the neural substrate normally involved in the development of a given ability is specific and, if so, when it becomes functionally specified and unique. Development of face processing was investigated in 5- to 17-year-old children who had a unilateral brain injury in the pre-, peri-, or postnatal period. In Studies 1 and 2, patients with a posterior injury involving the temporal regions exhibited a face-processing deficit that was independent of their age at test time. Even though differences were observed between the two hemispheres in face processing during infancy as well as in adults in cases of normal development, no clear differences between right and left injury were observed here in face-processing deficit. Poor postlesional face-processing plasticity seems to contrast with results of several studies on speech development after early unilateral injury. If the difference in the time window for postlesional plasticity between these two areas of competency is confirmed, it would suggest that the two kinds of abilities rely on neural cells which are sensitive to different plasticity factors. 相似文献
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Antonia D'Errico Walter F. Grigioni Michelangelo Fiorentino Paola Baccarinl Eugene Lamas Stella De Mitri Giuseppe Gozzetti Antonio M. Mancini Christian Brechot 《Pathology international》1994,44(2):131-137
Recent results obtained using molecular biology techniques have suggested a possible role for insulin-like growth factor II (IGF-II) in the pathogenesis of hepatocellular carcinoma (HCC). To investigate this phenomenon, a monoclonal anti-body was used against IGF-II to study 54 patients with HCC. The presence of HBsAg was also tested both in serum and liver tissue. A positive immunoreaction was found in 9/15 (60%) of the HCC arising in cirrhotic livers of patients who had serum markers for HBV (HBV+ positive patients). These results provide further evidence that HBV might play a role in the expression of IGF-II. In HCC of patients without any markers of HBV infection (HBV- negative patients), IGF–II was detected in 10/39 (25.6%) of the tumors, and in some benign neoplastic lesions. It was found not only in neoplastic cells but also in some dysplastic nodules. The speculation arises that IGF–II expression may play a role in some steps of hepato-carcinogenesis. 相似文献
44.
Wessels MW Berger RM Frohn-Mulder IM Roos-Hesselink JW Hoogeboom JJ Mancini GS Bartelings MM Krijger Rd Wladimiroff JW Niermeijer MF Grossfeld P Willems PJ 《American journal of medical genetics. Part A》2005,(2):171-179
Most nonsyndromic congenital heart malformations (CHMs) in humans are multifactorial in origin, although an increasing number of monogenic cases have been reported recently. We describe here four new families with presumed autosomal dominant inheritance of left ventricular outflow tract obstruction (LVOTO), consisting of hypoplastic left heart (HLHS) or left ventricle (HLV), aortic valve stenosis (AS) and bicuspid aortic valve (BAV), hypoplastic aortic arch (HAA), and coarctation of the aorta (CoA). LVOTO in these families shows a wide clinical spectrum with some family members having severe anomalies such as hypoplastic left heart, and others only minor anomalies such as mild aortic valve stenosis. This supports the suggestion that all anomalies of the LVOTO spectrum are developmentally related and can be caused by a single gene defect. 相似文献
45.
Is the outcome of in-vitro fertilization and embryo transfer treatment improved by spontaneous or surgical drainage of a hydrosalpinx? 总被引:4,自引:7,他引:4
Sowter MC; Akande VA; Williams JA; Hull MG 《Human reproduction (Oxford, England)》1997,12(10):2147-2150
A pilot study was designed to examine whether the outcome of embryo
transfer in women with a hydrosalpinx might be improved by surgical
drainage of the hydrosalpinx at the time of oocyte collection for in- vitro
fertilization treatment. A comparative, controlled but retrospective
analysis of the results was performed of all women with infective tubal
damage aged <40 years old, who had ovulatory cycles, a normal uterus and
a partner with normal spermatozoa. A standardized treatment regimen was
used. A maximum of three embryos were transferred. Hydrosalpinx was defined
by prior hysterosalpingography and/or laparoscopy with transcervical dye
injection. A total of 237 embryo transfer cycles in women with
hydrosalpinges (tubal distension not visible in 151, visible but not
drained in 30 and drained in 56) were compared with 705 embryo transfer
cycles in women with tubal disease but no hydrosalpinx. Results were
analysed in the first three cycles but also separately in the first cycle
to check for bias. Success rates were higher in the first cycle, but did
not significantly influence overall differences. Implantation rates were
significantly reduced overall in the hydrosalpinx group (8.0 versus 13.2%
for controls; P < 0.001), being 8.3% (P < 0.01) in the subgroup
without evident tubal distension and 7.5% (not significant) in the drained
hydrosalpinx group. This study shows that tubal damage with distal
occlusion is associated with a marked reduction in embryo implantation,
even in the absence of obvious fluid distension. Surgical drainage of
distended hydrosalpinges appears to offer no benefit.
相似文献
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A. D'Errico W. F. Grigioni M. Fiorentino P. Baccarini G. L. Grazi A. M. Mancini 《Pathology international》1994,44(9):682-687
The overexpression of p53 protein and the Ki67 proliferative index was evaluated in 96 hepatocellular carcinomas (HCC), 67 in cirrhotic livers and 29 in non-cirrhotic ones, and in 13 non-carcinomatous lesions, all surgically resected from Italian patients. Overexpression of p53 was detected only in carcinomatous lesions, and was significantly related to the grade of HCC ( P < 0.001). In fact, p53 was observed in 7/7 (100%) cases of grade IV, 13/43 (30.3%) of grade III, and 10/ 46 (21.7%) of grade II. The relationship between p53 and Ki67 scores was determined in serial sections from corresponding areas of both diffuse and patchy immunoreactivity. In the overall population, p53-positive tumors showed a significantly higher Ki67 score (15.9 ± 5.5% vs 9.2 ± 4.3% [ P < 0.001]). This observation was evident in all grades of HCC. 相似文献
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