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To investigate the correlation between argyrophilic nucleolar organizer regions (Ag-NORs)and the malignant potential of breast tumors, we analyzed Ag-NORs of cytological specimens obtained from 190 patients with various types of breast disease by preoperative aspiration biopsy. The average number of Ag-NORs per nucleus was defined as the Ag-NOR score. The Ag-NOR score was 5.7 +/- 1.7 in the group of women with breast carcinoma (n =70), 2.6= 0.4 in the group with fibroadenoma (n= 54) and 2.9= 0.6 in the group with mastopathy (n= 66). The level was significantly higher in breast carcinoma than in each benign disease(P < 0.001 in both cases). The score was 6.5 +/- 2.3 in the group with four or more metastatic lymph nodes (n = 21), 5.2+/- 1.2 in the group with one to three metastatic lymph node (n= 10) and 5.1+/- 1.1 in that with no metastatic lymph node (n = 39);the score was significantly (P < 0.05) higher in the groups with four or more metastatic lymph modes than in the other groups, respectively. Thus, a correlaton was observed between the Ag-NOR score and lymph node status. These data suggest that a higher Ag-NOR score reflects high-grade malignancy.  相似文献   
83.
We describe the case of a 73-year-old woman with secondary myelofibrosis who developed subcutaneous extramedullary hematopoiesis. Although extramedullary hematopoiesis has been generally observed in primary myelofibrosis, in this case it was seen in myelofibrosis secondary to polycythemia vera. Histological examination of the subcutaneous nodule revealed that the lesion included cells from the myeloid and megakaryocytic series. The skin lesion almost disappeared after treatment with hydroxyurea. We report here this rare manifestation in secondary myelofibrosis including a review of literature.  相似文献   
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Human leukocyte antigen (HLA) typing is essential to carry out HLA-class I restricted antigenic peptide-based cancer immunotherapy. To establish a one-step polymerase chain reaction-sequence-specific primer (PCR-SSP) method, we designed two novel HLA-A24-specific primer sets and determined the optimal conditions for specific amplification. Then, we performed HLA-A24 typing of two healthy donors' and 17 cancer patients' peripheral blood with serological typing and PCR-SSP typing. Eleven of the 19 cases were determined HLA-A24-positive by the PCR-SSP method precisely; however, five cases showed false positive with serological analysis. Thus, for HLA-A24 typing in the Japanese population, the PCR-SSP method is faster and more accurate than serological typing.  相似文献   
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Biological materials: a materials science approach   总被引:1,自引:0,他引:1  
The approach used by Materials Science and Engineering is revealing new aspects in the structure and properties of biological materials. The integration of advanced characterization, mechanical testing, and modeling methods can rationalize heretofore unexplained aspects of these structures. As an illustration of the power of this methodology, we apply it to biomineralized shells, avian beaks and feathers, and fish scales. We also present a few selected bioinspired applications: Velcro, an Al2O3-PMMA composite inspired by the abalone shell, and synthetic attachment devices inspired by gecko.  相似文献   
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BACKGROUND: Little information exists regarding the precise distribution of verapamil-sensitive atrial tachycardia originating from the vicinity of the atrioventricular node (V-AT). METHODS: In 12 patients with V-AT, we examined the spatial and topologic distribution of tachycardia origin relative to the His bundle (HB) site. The V-AT origin was divided into six areas: anterior (A-HB), posterior (P-HB), superior (S-HB), inferior (I-HB), lateral (L-HB), and septal (SP-HB) portion of HB catheter. Three dimensional distance between the distal pair of the electrodes of HB catheter and that of V-AT origin (DIS) was obtained by calculating the distances on the right and left anterior fluoroscopic images. Topologic distribution was expressed as the interval between the onset of the atrial electrogram of V-AT origin and that of HB catheter (INT). RESULTS: The tachycardia origin was observed at the P-HB in four, S-HB in two, I-HB in two, SP-HB in three, and L-HB in one patient. The tachycardia cycle length, DIS, and INT were 369 +/- 67 ms, 12 +/- 3 mm, and -12 +/- 8 ms, respectively. After successful ablation of initial V-AT (1st V-AT), V-AT with a different origin (2nd V-AT) was induced in five patients. The tachycardia origin, tachycardia cycle length, DIS, and INT of the 2nd V-AT (P-HB in three, S-HB in one, and SP-HB in one patient; 333 +/- 66 ms, 8 +/- 3 mm, and -11 +/- 4 ms, respectively) were not different from those of 1st V-AT. CONCLUSIONS: V-AT often shows a shift in tachycardia origin to another site where the spatial and topologic distributions are similar to those of 1st V-AT.  相似文献   
90.

Objectives  

We investigated dampness/mold in schools and dwellings, and food habits and subjective symptoms in elementary school pupils, in order to clarify the effect of dampness and food habits on subjective symptoms in elementary school pupils.  相似文献   
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