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41.
Laryngeal pleomorphic rhabdomyosarcoma   总被引:2,自引:0,他引:2  
A case of an extremely unusual tumor of the larynx, pleomorphic rhabdomyosarcoma, is presented with a review of literature. This is the fifth case of this malignancy described in the larynx in the English language literature. A histopathological diagnosis was made with immunohistochemistry and electron microscopy. In contrast to other reported cases, the tumor in the present case had a very aggressive behavior. Despite radical surgery involving total laryngectomy and neck dissection followed by radiation therapy, the patient died of disease 8 months following treatment. Received: 14 March 1997 / Accepted: 23 January 1998  相似文献   
42.
This article discusses issues to be considered by nurse researchers when groups should be used as the unit of randomization. Advantages and disadvantages are presented, with statistical calculations needed to determine the effective sample size. Examples of these concepts are presented using data from the Black Cosmetologists Promoting Health Program. Different hypothetical scenarios and their impact on sample size are also presented. Given the complexity of calculating the sample size when using groups as the unit of randomization, it is advantageous for researchers to work closely with statisticians when designing and implementing studies that anticipate the use of groups as the unit of randomization.  相似文献   
43.
The stimulation of human γδ T cells by mycobacteria occurs through recognition of four distinct nonpeptide phosphorylated antigens termed TUBag1–4. Among these latter, TUBag4 has already been biochemically characterized as a γ-X derivative of 5′-deoxythymidine triphosphate (Constant, P., Davodeau, F., Peyrat, M. A., Poquet, Y., Puzo, G., Bonneville, M. and Fournié, J.-J., Science 1994. 264: 267). However, despite chemical synthesis of weakly stimulatory nucleotide-containing analogs, these mycobacterial compounds remained the sole nucleotide-containing antigens actually isolated from natural sources. Here, we present the complete isolation of the TUBag3 antigen from Mycobacterium fortuitum and demonstrate that this nonpeptide molecule contains a 5′-UTP nucleotide moiety. On selected Vγ9/Vδ2 clones, T cell responses can be triggered with nanomolar concentrations of TUBag3. Like crude mycobacterial extracts, this purified nucleotide conjugate elicits a strong polyclonal response of γδ PBL from healthy donors. Furthermore, we present evidence that this compound is distinct from the recently synthesized γ-isopentenyl 5′-UTP, a nucleotide conjugate of isopentenyl pyrophosphate that was found to be stimulatory for human γδ T cells (Tanaka, Y., Morita, C. T., Tanaka, Y., Nieves, E., Brenner, M. B. and Bloom, B. R., Nature 1995. 375: 155). Since it appears that both mycobacterial nucleotide antigens are molecules structurally related to peculiar precursors of nucleic acid synthesis, we propose that TUBag-reactive T cells might be specifically devoted to surveillance of proliferating cells.  相似文献   
44.
Two Puralpha-binding proteins (PurBPs) were found in nuclear extract from mouse brain during P4-P10 by the overlay assay. At P14, they were decreased significantly in nuclear extract and increased in the S3 fraction, indicating their dynamic translocation during development. Western blot analysis also demonstrated concomitant translocation of Puralpha with the PurBPs during P7-P14, when neuronal circuit proceeds. Immunocytochemical study with cultured hippocampal neurons from rat E18 confirmed that nuclear Puralpha was translocated to cytoplasm after plating for 7-14 days. These results suggest that spatiotemporal translocation of Puralpha with the PurBPs from nuclei to cytoplasm has a crucial role in neuronal development.  相似文献   
45.
Members of the epidermal growth factor (EGF) family and their receptors are involved in many cellular processes, including proliferation, migration, and differentiation. We have previously reported that these growth factors are expressed and have specific regulatory functions in an organ-like culture model of normal human urothelial cells. Here, we used this model to investigate the involvement of EGF receptor (EGFR) in human urothelial regeneration. Three 4-mm-diameter damaged areas were made in confluent normal human urothelial cell cultures with a biopsy punch. Regeneration was measured, on fixed stained cultures, with an image analyzer, at 4, 24, and 48 hours after injury. Cell proliferation was assessed by 5-bromo-2-deoxyuridine incorporation. To identify EGF family factors potentially involved in the healing process, we studied the effect of these factors on damaged confluent cultures and the level of expression of mRNAs extracted from these cultures. EGFR inhibition of the proliferation and migration of urothelial cells was tested with (1). a specific tyrosine kinase inhibitor (AG1478) and (2). a blocking anti-EGFR antibody (LA22). Exogenously added amphiregulin, EGF, transforming growth factor-alpha and heparin-binding EGF (HB-EGF) stimulated urothelial regeneration. The damaged areas were repaired by regrowth within 48 hours. Both AG1478 and LA22 inhibited the repair (by 50% and 30%, respectively), as well as proliferation and migration. This regeneration was accompanied by increased HB-EGF mRNA expression in cultures of cells from four of six subjects, but no corresponding change in EGFR protein level was observed. These results indicate that the EGFR signaling pathway is involved in urothelial regeneration. Our data support an autocrine role of HB-EGF in this process and suggest that the EGFR pathway is a potential therapeutic target for modulating urothelial cell proliferation.  相似文献   
46.
The stress-induced extracytoplasmic sigma factor E (SigE) of Mycobacterium tuberculosis shows increased expression after heat shock, sodium dodecyl sulfate treatment, and oxidative stress, as well as after phagocytosis in macrophages. We report that deletion of sigE results in delayed lethality in mice without a significant reduction of bacterial numbers in lungs.  相似文献   
47.
On December 31, 2001, 2486 patients with terminal renal failure received dialysis treatment in Croatia. Only one third of the patients are registered on the national waiting list for cadaveric kidney transplant. In most of the others, transplantation is impossible because of comorbidity. This is mainly due to the steadily growing age of the dialytic population and therefore a higher incidence of cardiovascular disease and diabetes. Still, evaluation of the potential recipients of cadaveric kidney transplant, registered on the waiting list, often reveals contraindications for transplantation. The aim of this study was to determine the incidence and type of contraindications in transplant candidates, found during immediate preoperative evaluation. Analysis of these data should help in determining how contraindications can be early detected and prevented. Before registering onto the national waiting list transplant candidates need to be thoroughly investigated including detailed history, physical examination, routine diagnostic procedures and additional examinations, if needed, to exclude or evaluate the possibly existing contraindications for transplantation. During the period from January 1997 until June 2002, 145 potential recipients from the national waiting list were referred to the Rijeka University Hospital Center and evaluated for kidney transplantation. Eighty-eight patients underwent transplantation. Preoperative evaluation revealed contraindications for transplantation in 52 (35.9%) candidates. Twenty-two (15.2%) patients had a positive cross-match with donor lymphocytes, 6 (4.1%) patients refused transplantation, and in 24 (16.6%) patients serious comorbidity was the reason for not being accepted for transplantation and for their withdrawal from the national waiting list. Comorbidity was mainly due to cardiovascular disease (12 patients--8.3%) and infection (8 patients--5.5%). These data show a high incidence of contraindications found during the immediate preoperative evaluation of potential kidney recipients. It was the case in more than one third of patients. During the evaluation of potential candidates for kidney transplantation special attention should be addressed to the presence of cardiovascular morbidity and infection. Peripheral vascular occlusive disease, cardiac status and/or cerebrovascular disease should be evaluated. Measures used to treat or reduce the development of complications include an optimal control of blood pressure, serum phosphate, hyperparathyroidism, dyslipidemia, and renal anemia. The sites of infection must be treated and eradicated, because immunosuppressive treatment is a threat to the transplant recipient's life. The second most common cause of refusal of potential candidates was a positive cross-match with donor lymphocytes. Sensitization to human leukocyte antigens can be prevented by the avoiding of blood transfusions and use of erythopoietin in treating renal anemia. To minimize the morbidity and mortality, the potential kidney recipients should undergo rigorous selection and thorough evaluation before including them into the waiting list for kidney transplantation. Afterwards, regular examinations are obligatory to reveal contraindications, proceed to medical interventions and treat concomitant diseases in time, which can influence the patient's survival. In case that contraindications for transplantation arise, the patient must be temporarily or definitely removed from the waiting list.  相似文献   
48.
Cranial sutures and craniometric points detected on MRI   总被引:2,自引:0,他引:2  
The main goal of the study was to determine on MRI the cranial sutures, the craniometric points and craniometric measurements, and to correlate these results with classical anthropometric measurements. For this purpose, we reviewed 150 cerebral MRI examinations considered as normal (Caucasian population aged 2049 years). For each examination we individualized 11 craniometric landmarks (Glabella, Bregma, Lambda, Opisthocranion, Opisthion, Basion, Inion, Porion, Infra-orbital, Eurion) and three measurements. Measurements were also calculated independently on 498 dry crania (Microscribe 3-DX digitizer). To validate the MRI procedure, we measured four dry crania by MRI and with compass or digital caliper gauges. Cranial sutures always appeared without signal (black), whatever the MRI sequence used, and they are better visualized with a 5 mm slice thickness (compact bone overlapping). Slice dynamic analysis and multiplanar reformatting allowed the detection of all craniometric points, some of these being more difficult to detect than others (Porion, Infra-orbital). The measurements determined by these points were as follows: VertexBasion height=135.66±6.56 mm; EurionEurion width=141.17±5.19 mm; GlabellaOpisthocranion length=181.94±6.40 mm. On the midline T1-weighted sagittal image, all median craniometric landmarks can be individualized and the GlabellaOpisthocranion length, VertexBasion height and parenchyma indices can be calculated. Craniometric points and measurements between these points can be estimated with a standard cerebral MRI examination, with results that are similar to anthropometric data.  相似文献   
49.
Relating cell and tissue mechanics: Implications and applications   总被引:1,自引:0,他引:1  
The Differential Adhesion Hypothesis (DAH) posits that differences in adhesion provide the driving force for morphogenetic processes. A manifestation of differential adhesion is tissue liquidity and a measure for it is tissue surface tension. In terms of this property, DAH correctly predicts global developmental tissue patterns. However, it provides little information on how these patterns arise from the movement and shape changes of cells. We provide strong qualitative and quantitative support for tissue liquidity both in true developmental context and in vitro assays. We follow the movement and characteristic shape changes of individual cells in the course of specific tissue rearrangements leading to liquid-like configurations. Finally, we relate the measurable tissue-liquid properties to molecular entities, whose direct determination under realistic three-dimensional culture conditions is not possible. Our findings confirm the usefulness of tissue liquidity and provide the scientific underpinning for a novel tissue engineering technology. Developmental Dynamics 237:2438-2449, 2008. (c) 2008 Wiley-Liss, Inc.  相似文献   
50.
We report the results of reduced-intensity unrelated cord blood transplantation (RI-UCBT) in patients with advanced malignant lymphoma. Twenty patients (median age, 46.5 years; range, 27-66 years) underwent RI-UCBT with a preparative regimen consisting of fludarabine 125 mg/m2 , melphalan 80 mg/m 2 , and 4 Gy of total body irradiation. The median infused total cell dose was 2.75 x 10(7)/kg (range, 2.3-3.4 x 10(7)/kg). Graft-versus-host disease (GVHD) prophylaxis was composed of cyclosporine or tacrolimus alone. Fifteen patients achieved primary neutrophil engraftment after a median of 20 days. Eight patients developed grade II to IV acute GVHD, and 2 developed chronic GVHD. Of the 16 patients with evaluable disease, 10 achieved a complete response. Primary disease recurred in 1 patient, and transplant-related mortality within 100 days occurred in 8 of 20 patients. The estimated 1-year probability of progression-free survival was 50%. These data suggest that RI-UCBT is a feasible option for patients with refractory lymphoma who lack an HLA-matched donor.  相似文献   
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