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21.
BACKGROUND: Preimplantation genetic diagnosis (PGD) is a technique which is often related to emotional debates because of its ethical and social implications. Worldwide there are different forms of legislation; Germany constitutes an interesting case because of the historical background concerning eugenics and dealing with handicapped persons at the time of national socialism. PGD is currently not legal but there are still polarized positions and legalization remains an issue. Studies about the attitudes of the general population towards PGD are rare. METHODS: Data were collected in a representative survey carried out in November 2003. Subjects were 2110 persons in Germany aged 18-50 years. RESULTS AND CONCLUSIONS: Respondents had little knowledge about PGD. There were incorrect assumptions about the diagnostic possibilities and a lack of basic genetic knowledge. A tendency towards a general acceptance of PGD for medical indications was found. Non-medical indications such as sex selection were generally not accepted. It could be observed that respondents who already had a notion about PGD overestimated the diagnostic possibilities and would eventually use PGD in the future more than respondents who had never heard about PGD before.  相似文献   
22.
We report a case of a 42-yr-old woman with Langerhans cell histiocytosis (LCH) confined to the thyroid and associated with lymphocytic thyroiditis and a papillary microcarcinoma. This patient remains free of symptoms 14 mo after surgery. Thyroid LCH is rare. In children, it usually occurs as part of a multisystemic disease, whereas it is usually exclusive in adults. Isolated thyroid LCH is frequently associated with another thyroid disease, especially lymphocytic thyroiditis, suggesting that it is a reactive process rather than a neoplastic proliferation. The prognosis of isolated thyroid LCH is good. However, because it can rarely precede or reveal a multisystemic disease, additional investigations as well as a prolonged follow-up are justified.  相似文献   
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Mammary gland adenomyoepitheliomas are benign complex mammary gland tumors composed of neoplastic cells of epithelial and myoepithelial origins, described in many species (humans, dogs, cats, rats) and rarely in mice. We report here an adenomyoepithelioma in a C57BL/6 female mouse. Histologically, tubes and cords formed by neoplastic epithelial cells were separated by bundles of neoplastic myoepithelial cells in a clear and partially mucinous matrix. The tumor displayed characteristics of a benign neoplastic proliferation with a compressive growth pattern, and moderate cellular pleomorphism and mitotic index. At immunohistochemistry, the epithelial cells were strongly cytokeratin positive; the myoepithelial cells were weakly cytokeratin positive and strongly smooth muscle actin positive. This is to our knowledge, the first report of a mammary gland adenomyoepithelioma in a C57BL/6 mouse.  相似文献   
25.
The majority of peripheral blood γδ T cells in human adults expresses T cell receptors (TCR) with identical V regions (Vγ9 and Vδ2). These Vγ9Vδ2 T cells recognize the major histocompatibility complex (MHC) class I-deficient B cell line Daudi and broadly distributed nonpeptidic antigens present in bacteria and parasites. Here we show that unlike αβ or Vγ9? γδ T cells, the majority of Vγ9Vδ2T cells harbor natural killer inhibitory receptors (KIR) (mainly CD94/NKG2A heterodimers), which are known to deliver inhibitory signals upon interaction with MHC class I molecules. Within Vγ9δ2 T cells, KIR were mainly expressed by clones exhibiting a strong lytic activity against Daudi cells. In stark contrast, almost all Vγ9Vδ2 T cell clones devoid of killing activity were KIR?, thus suggesting a coordinate acquisition of KIR and cytotoxic activity within Vγ9Vδ2 T cells. In functional terms, KIR inhibited lysis of MHC class I-positive tumor B cell lines by Vγ9Vδ2 cytotoxic T lymphocytes (CTL) and raised their threshold of activation by microbial antigens presented by MHC class I-positive cells. Furthermore, masking KIR or MHC class I molecules revealed a TCR-dependent recognition by Vγ9Vδ2 CTL of ligands expressed by activated T lymphocytes, including the effector cells themselves. Taken together, these results suggest a general implication of Vγ9Vδ2 T cells in immune response regulation and a central role of KIR in the control of self-reactive γδ CTL.  相似文献   
26.
Summary Diagnosis of malignant histiocytosis (MH) was confirmed in 16 patients. Stage at diagnosis was I–II in nine, and III–IV in seven patients. Poor prognosis and B-symptoms were correlated to advanced stages. Bone marrow biopsy proved most useful to verify organ involvement. Scintigraphy and computerized tomography, too, detected organ involvement in some patients and were helpful for judging response to therapy. Relapses after radiotherapy were frequent. Polychemotherapy using CHOP-combination is recommended for most patients and may in stages I–II be supplemented by primary or secondary involved or extended field irradiation and in more advanced stages by mainbulk-irradiation. The value of prophylactic CNS-therapy remains controversial. Pathophysiological aspects and differential diagnosis are discussed.  相似文献   
27.
A valine to isoleucine mutation at residue 180 was identified in a French patient with Creutzfeldt-Jakob disease (CJD). The mutation is located in the close vicinity of one of the two N-glycosylation sites of the cellular prion protein (PrPC). Western blot analysis revealed accumulation in the brain of the pathogenic proteinase K-resistant PrP (PrPSc) isoform with the notable absence of the diglycosylated band. The mutant protein expressed in CHO cells was correctly glycosylated, suggesting that the atypical glycosylation pattern of PrPSc was not due to the mutation at position 180. These results suggest that the diglycosylated form of the mutant PrP180I prevents its conversion into the pathogenic mutant form PrPSc180I, supporting a central role of N-linked glycan chains in the PrP conversion process.  相似文献   
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The evaluation of the professional practices (EPP) is obligatory for all the physicians since July 1, 2005 for a first five-year period. It represents one of the components of the continuous medical training (CMT). The French Society of Blood Transfusion and National Institute of Blood Transfusion are the promoters of the EPP in transfusion technology and medicine. Initially, the programs of EPP will be conceived and controlled by experts and will relate to their basic activities. During a five years cycle, the physician taking part in a program must validate a specific action and take part in a rolling programme. At the end of the programme, the physician will receive a certificate issued by National Institute of Blood Transfusion and will have to submit it to a committee placed under the responsibility of the regional physicians' committee.  相似文献   
30.
Various salient histological features were rated from + to +++ in a semiquantitative evaluation of a series of 155 cases of fibrous histiocytoma. Relations between individual histological features, as well as between histological findings, localisation and size of lesions, and age or sex of the patient were tested statistically. Most impressive was an inverse proportional relationship between cellular and fibrillar densities: highly cellular fibrous histiocytomas chiefly showed little fiber formation. Accordingly, cases with marked fiber formation were distinguished by low cellularity. Based on this statistically significant relation, 3 subtypes could be classified on a scale of increasing fiber formation and decreasing cellular density. The majority of cases showed medium cellularity and fibrillar density, with distinct storiform (spokewheel or "whirlygig") pattern which is compatible with typical storiform histocytoma, including clincally progressive, recurrant FH and/or "dermatofibrosarcoma protuberans". The typical patient was more frequently female than male, 40 years of age with a 0.5 to 1.0 cm size tumor node in the lower extremities located in the corium, often with beginning infiltration of the subcutaneous fat tissue.  相似文献   
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