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1.
We studied an unusual sarcoma with morphologic features diagnostic of epithelioid sarcoma by conventional light microscopy, transmission electron microscopy, and immunohistochemistry. The primary tumor, which was located in the deep soft tissues of the buttock of a 32-year-old woman, and its metastases to lymph nodes, liver, and lung were available for investigation. The histomorphological and ultrastructural appearance of the primary tumor and its metastatic deposits were typical of epithelioid sarcoma. Immunohistochemistry revealed a strong and uniform reactivity for vimentin in both the primary tumor and its metastases. In contrast, a marked cytoskeletal heterogeneity became evident for cytokeratins and neurofilaments, which were observed exclusively in lymph node metastasis. To our knowledge, the observation of neurofilaments in epithelioid sarcoma has not previously been reported.  相似文献   
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Purpose: To demonstrate HRCT findings and their therapeutic relevance in suspected congenital hearing disorders. Material and Methods: It was checked in 96 young patients if HRCT findings of the temporal bone could explain functional findings. Furthermore, the therapeutic consequences were noted. Results: Normal CT and normal functional findings were obtained in 49 temporal bones (TB). In conductive hearing loss (41 TB), dysplasias of the conducting apparatus (37 TB) and inflammatory changes (3 TB) were found. Combined hearing loss (18 TB) was clarified completely or partially in half the cases. There were 22 dysplasias of the inner ear, 3 dysplasias of the middle ear, 1 abandoned examination (2 TB), and 55 normal CT findings in senorineural hearing disorders (82 TB). 1 retardate had a malformation of the inner ear and, contralaterally, inflammatory middle ear. In cases of vestibular disorders (24 TB), 14 malformations of the inner ear were detected. An indication for an operation was given in 23 TB. In 22 TB, it was contraindicated. The CT was one preliminary examination to a cochlea implant in 19 patients. The therapy was carried on with hearing devices in the other patients. Conclusion: HRCT is an important method in diagnosis and therapeutic planning of suspected malformations of the temporal bone.   相似文献   
4.
Hexokinase I (ATP: -hexose 6-phosphotransferase, EC 2.7.1.1) is the first enzyme required in the metabolism of glucose in the central nervous system and plays a major role in regulation of the cerebral glycolytic rate. The distribution of hexokinase I mRNA was examined throughout the central nervous system of the rat by use of oligonucleotide probes and in situ hybridization histochemistry. In the rhinencephalon, strong hexokinase I mRNA labeling was demonstrated in the glomerular, mitral, internal granular, and internal plexiform layers, whereas the olfactory nerve, external plexiform, and subependymal layers and ependyma were devoid of labeling. Within the telencephalon, strong labeling was present in all layers (with the exception of the molecular layer) of the cerebral cortex, in the septum, in CA1-4 and dentate gyrus of the hippocampus, and in several amygdaloid nuclei. There was only weak labeling in the nucleus accumbens and caudate putamen. In the diencephalon, there was in general a strong labeling in the epithalamus, in several thalamic nuclei, including the anteriodorsal, anterioventral, anteriomedial, reticular, paravetricular, intermediodorsal, anteriomedial, interanteriomedial, rhomboid, reuniens, and parafascicular thalamic nuclei. Several hypothalamic regions, including the subfornical organ, the medial preoptic area, the suprachiasmatic, supraoptic, paraventricular, dorsomedial, ventromedial nuclei, and the zona incerta, were strongly labeled. In the mesencephalon, there was particularly strong labeling in the pars compacta and reticulata of the substantia nigra, central gray, and red nucleus, in the Darkschewitsch nucleus, and in the medial accessory oculomotor nucleus. In the rhombencephalon, there was strong hybridization in all raphe nuclei, pontine, tegmental, lateral parabrachial, olivary nuclei, and several cranial motor nuclei. All neurons of the locus ceruleus were heavily labeled. Very strong labeling was present in Purkinje and granular cells of the cerebellar cortex. Neurons of the medulla oblongata area postrema, nucleus tractus solitarius, reticular nucleus, nucleus cuneatus and several motor nuclei were strongly labeled. In the spinal cord, labeled cells were present in all laminae, and also neurons of the dorsal root ganglion were heavily labeled. Hexokinase I mRNA was also demonstrated in the epithelium lining the choroid plexus. In the E15 fetus, very strong labeling was seen in the liver, heart, and trigeminal ganglion, with less intense labeling in the brain and other tissues having more moderate labeling. Administration of 2% saline as drinking water resulted in a marked increase in hexokinase I mRNA in the magnocellular neurons of the supraoptic and paraventricular nuclei. In summary, the results show extensive neuronal distribution of hexokinase I mRNA with regional differences in the expression pattern.  相似文献   
5.
The cytodiagnosis is a simple noninvasive procedure which requires close cooperation between the clinician and an experienced cytologist. It enables important diagnostic and therapeutic recommendations on the basis of morphological findings. A total of 1000 smears of the larynx obtained from 430 patients with chronic laryngitis were examined. In a case- controlled study of 143 patients with chronic hyperplastic laryngitis, smokers and/or laryngeal dysplasia patients with a 9.6% risk for malignant transformation, were identified as risk groups needing cytological screening at intervals of 6 months to a year. In the cytodiagnostic evaluations the main emphasis should be placed on dysplasias and metaplasias. Performed systematically, cytologically assisted early examination of the larynx expands the diagnostic possibilities, and is a useful supplement to biopsy. In the risk group chronic hyperplastic laryngitis, cytodiagnosis can be used to screen suspicious lesions for tumors. Although it cannot replace histological examination, it is highly suitable for the early diagnosis and effective follow-up of precancerous epithelial changes of the larynx.  相似文献   
6.
Crosslineage T-cell receptor delta (TCR delta) rearrangements are widely used as tumor markers for the follow up of minimal residual disease in childhood B-precursor acute lymphoblastic leukemia (ALL) by polymerase chain reaction (PCR). The major drawback of this approach is the risk of false-negative results due to clonal evolution. We investigated the stability of V delta 2D delta 3 rearrangements in a group of 56 childhood B-precursor ALL patients by PCR and Southern blot analysis. At the PCR level, V delta 2D delta 3-to-J alpha rearranged subclones (one pathway for secondary TCR delta recombination) were demonstrated in 85.2% of V delta 2D delta 3-positive patients tested, which showed that small subclones are present in the large majority of patients despite apparently monoclonal TCR delta Southern blot patterns. Sequence analysis of V delta 2D delta 3J alpha rearrangements showed a biased J alpha gene usage, with HAPO5 and J alpha F in 26 of 32 and 6 of 32 clones, respectively. Comparison of V delta 2D delta 3 rearrangement status between diagnosis and first relapse showed differences in seven of eight patients studied. In contrast, from first relapse onward, no clonal changes were observed in six patients studied. To investigate the occurrence of crosslineage TCR delta rearrangements in normal B and T cells, fluorescence-activated cell sorter-sorted peripheral blood CD19+/CD3- and CD19-/CD3+ cell populations from three healthy donors were analyzed. V delta 2D delta 3 rearrangements were detected at low frequencies in both B and T cells, which suggests that V delta 2-to-D delta 3 joining also occurs during normal B-cell differentiation. A model for crosslineage TCR delta rearrangements in B-precursor ALL is deduced that explains the observed clonal changes between diagnosis and relapse and is compatible with multistep leukemogenesis of B-precursor ALL.  相似文献   
7.
Infiltration is a frequent complication of intravenous therapy using peripheral venous lines in neonatal patients. In a randomized trial of two catheter materials, Vialon (Becton Dickinson) and Teflon (DuPont), we studied 19 putative risk factors for infiltration, including 11 infusates, in 772 peripheral venous lines in patients aged 1 to 67 days. The best-fit Cox regression model identified six significant predictors of infiltration (P less than .05): catheter material, age, anatomic insertion site, hyperalimentation, and use of furosemide and dopamine. For the subsample of patients weighing less than or equal to 1500 g, a second Cox regression model identified time spent inserting the catheter and the number of insertion attempts as additional significant predictors. These multivariate models showed that Vialon catheter material reduced the risk of infiltration by 18% (95% CI, 1% to 32% reduction) in the total sample and by 35% (95% CI, 15% to 50% reduction) in the higher risk low-weight (less than or equal to 1500 g) subsample.  相似文献   
8.
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   
9.
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   
10.
The world's first deliveries of normal babies after use of flow cytometric separated human sperm cells (MicroSort) for preconception gender selection are reported. Offspring were of the desired female gender in 92.9% of the pregnancies. Most of these pregnancies and births were achieved after simple intrauterine insemination.   相似文献   
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