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1.
To evaluate the correlation between the histological grade and the prognosis, we reviewed 100 cases of prostatic cancer according to the Japanese General Rules of Prostatic Cancer (JGRPC) and Gleason grading system. The study led to the following results: (1) There was a close relation between the JGRPC grade and Gleason score (GS). (2) The JGRPC grade and Gleason score were equally concerned with the clinical stage. (3) There were significant differences in survival rate between well and moderately, well and poorly differentiated groups by the JGRPC grading system, and between GS 2-4 and GS 5-7, GS 2-4 and GS 8-10 groups by Gleason score. (4) In proportion to the JGRPC grade, the cancer death rate increased linearly in each stage. (5) When the patients were grouped according to their JGRPC grades of main lesion and accompanied lesion, the cancer death rate increased in the cases with lower differentiated elements. We conclude that the JGRPC grading system is easily comprehensible, and equal with the Gleason grading system to predict the prognosis of prostatic cancer.  相似文献   
2.
Summary The histological grades of prostatic carcinoma, as defined by Gleason, were correlated with three methods of morphometry in 254 step-sectioned prostates obtained at autopsy. The variables studied were 1) the number of tumours in each prostate; 2) bilaterality and 3) tumour volume. Each characteristic yielded a statistically significant correlation with histological grade. The strongest correlations were obtained using tumour volume. These autopsy studied help to explain the inconsistent results obtained from morphometric analyses of surgical material, and lend support to the Gleason system as a means of predicting tumour behavior.Supported in part by research contracts PH 64-10, NCI-72-3213, N01-CP-53521; Grant R01-CA-33644; and the Grant-in-Aid for Cancer Research (33) from the Ministry of Health and Welfare  相似文献   
3.
Human prostate cancers frequently show loss of heterozygosity at loci on the short arm of chromosome 8. In order to take a step toward isolation of the putative tumor suppressor gene(s) on 8p via positional cloning, we performed high-resolution deletion mapping in 46 prostate cancers (stage B, 20 cases; stage C, 8 cases; endocrine therapy-resistant cancer death, 18 cases) using new 12 restriction fragment length polymorphism markers for this chromosomal region. Allelic losses were observed in 25 of the 44 cases (57%) that were informative with at least one locus. Detailed deletion mapping defined a 1.2 Mb commonly deleted region at 8p22-p2 1.3 flanked by markers cMSR-32 and C18- 105 1. A second region of common deletion was identified between C18-1312 and C18-494 at 8p21-8p11.22, suggesting that at least two tumor suppressor genes associated with prostate cancer are present on chromosome arm 8p. Allelic losses on 8p were observed more frequently in the cancer death cases (14/17, 82%) than in early-stage tumors (11/27, 40%; P < 0.01, Fisher's exact test). In two out of 7 patients for whom DNA was available from metastatic cancers as well as from normal tissues and primary tumors, the primary cancer foci had no detectable abnormality of 8p, but the metastatic tumors showed loss of heterozygosity. These results suggest that inactivation of tumor suppressor genes on 8p plays an important role in the progression of prostate cancer. © 1995 Wiley-Liss, Inc.  相似文献   
4.
Sarcomatoid carcinoma is a rare variant of malignant tumor arising from the urinary tract. This tumor had been termed carcinosarcoma because of its carcinomatous and sarcomatous components. There is still some confusion in the terminology between true carcinosarcoma and sarcomatoid carcinoma; however, the latter is now regarded as primarily a malignant epithelial tumor with pseudosarcomatous transformation.
Four cases of sarcomatoid carcinoma arising from the urinary tract are reported. The patients were a 77 year old female, and three males aged 62, 69 and 80 years. All but the eldest patient complained of gross hematurla. Surgical removal was performed in the younger three cases, and an autopsy was done in the remaining case. All the tumors were macroscopically polypoid. Histopathologic examination revealed fasciculated spindle-cell tumors with myxold stroma or malignant fibrous histiocytoma-like spindle cell tumors. The epithelial nature was proven in these sarcomatous cells by immunohistochemical andlor electron-microscopic examinations. Only a small amount of squamous cell carcinoma components was also evident in the latter three cases. Although the younger three patients were alive at 44, 23 and 39 months'follow-up, respectively, constant careful monitoring Is recommended.  相似文献   
5.
A case of Hodgkln's disease (HD), lymphocyte depression (LD) type In an Immunosuppressive patient is described. The patient was a 48-year-old male and his parents were born In the Kyushu area, which is an endemic area for adult T cell lymphomaheukemla (ATL). He was seropositive for ATL virus (ATLV, also referred to as HTLV-I) and showed a marked Immunosuppressive condition. He developed LD-HD and Pneumocystis carinii pneumonia, and died due to respiratory failure. The Immunohistochemical and in situ hybridization analyses revealed that the Reed-Sternberglike cells In the lymph node biopsy sample were positive for Ber-H2 (CD30), Leu-M1 (CD15), L-26 (CD20), Bcl-2, p53 and EBER, the viral genome of Epstein-Barr virus (EBV).  相似文献   
6.
7.
A 59-year-old woman with leukorrhea. Aspiration smears were obtained from the uterine cavity. The dominant cellular components were fibrogenic sarcomatous cells, which had ill-defined lacy cytoplasm and a single nucleus with finely granular chromatin. There were occasional naked giant cells, and intracytoplasmic eosinophilic granules. Another infrequent cellular component was adenocarcinoma cells. Histopathologically, adenocarcinoma and spindle cell sarcoma were equivalently identified. Twenty-two cases of homologous carcinosarcoma of the uterine corpus were reviewed cytologically in Japan. Cytodiagnosis before treatment was positive for malignancy of carcinosarcoma in 28.6%. Characteristic cytological findings of this case were the presence of flat sheets of atypical cells with broad cytoplasm. These findings suggest epithelial features. However, the finely granular chromatin pattern and smooth nuclear membrane indicate sarcomatous cells.  相似文献   
8.
BackgroundThe diagnostic assessment of the level of difficulty in treating patients who need prosthodontic care is useful to establish a medico-economically efficient system with primary care dentists and prosthodontic specialists.Materials and methodsA multi-axis assessment protocol was established using the newly established treatment difficulty indices. The protocol contains Axis I: oral physiological conditions (e.g., teeth damage and/or missing teeth); Axis II: general health and sociological conditions (e.g., medical disorders); Axis III: oral health-related quality of life (OHRQOL; e.g., oral health impact profile: OHIP); and Axis IV: psychological health (e.g., mood, anxiety, somatoform disorders). A preliminary study on the test–retest consistency of the protocol was conducted to check the levels of reliability of the indices prior to a large-scale, multi-center cohort study on the validity of the protocol.ResultsThe test–retest consistency in terms of the oral physiological condition (Axis I) after data reduction was 0.63 for patients with teeth problems, 0.95 for partially edentulous patients, and 0.62 for edentulous patients. The reliability for general health and sociological conditions (Axis II), OHRQOL (Axis III), and psychological health (Axis IV) were 0.88, 0.74, and 0.61, respectively. These values reflect either “sufficient agreement” or “excellent agreement” in accordance with the criteria established by Landis and Koch (1977) [1].ConclusionThis protocol is the first multi-axis assessment scheme introduced for prosthodontic treatment with sufficient reliability. This new system is therefore expected to have a significant impact on future dental diagnostic nomenclature systems.  相似文献   
9.

Objectives

The purpose of this study is to evaluate the effects of multiple firings on the mechanical properties and microstructure of veneering ceramics used with zirconia frameworks.

Methods

Five different veneering ceramics for zirconia frameworks were used: Vintage ZR (ZR), Cerabien ZR (CZR), Vita VM9 (VM9), Cercon ceram KISS (KISS), IPS e.max ceram (e.max), and one veneering ceramic used for PFM frameworks: Vintage MP (MP). Twenty specimens were fabricated of each veneering ceramic. Ten specimens were fired twice and another ten specimens were fired ten times. Three-point flexural strength following the ISO 6872 and Vickers hardness were measured, and fracture toughness (KIC) was calculated. Density and porosity were determined. Specimens were characterized using X-ray diffraction (XRD) and scanning electron microscopy (SEM).

Results

For all materials, density increased and porosity decreased after 10 firings. Significant differences in density and porosity were observed between 2 and 10 firings, with the exception of VM9 (P < 0.05). There were no significant differences in flexural strength between 2 and 10 firings except for MP. The Vickers hardness of ZR, VM9, KISS and MP increased significantly after 10 firings (P < 0.001). There were no significant differences in fracture toughness for ZR, CZR, VM9 and MP between 2 and 10 firings. However, e.max underwent a significant increase in fracture toughness (P = 0.000), and there was a significant decrease in the toughness of KISS after 10 firings (P = 0.007).

Conclusion

Multiple firings could be effective for improving the densification and the hardness of veneering ceramics for zirconia restorations.

Clinical significance

By 10 firings, the density and hardness of the veneering ceramics used with zirconia frameworks were raised, and porosity was reduced. However, no significant changes occurred in flexural strength, fracture toughness or microstructure.  相似文献   
10.
Background: Occlusal overloading causes peri‐implant bone resorption. Previous studies examined stress distribution in alveolar bone around commercial implants using three‐dimensional (3D) finite element analysis. However, the commercial implants contained some different designs. The purpose of this study is to reveal the effect of the target design on peri‐implant bone stress and abutment micromovement. Methods: Six 3D implant models were created for different implant–abutment joints: 1) internal joint model (IM); 2) external joint model (EM); 3) straight abutment (SA) shape; 4) tapered abutment (TA) shapes; 5) platform switching (PS) in the IM; and 6) modified TA neck design (reverse conical neck [RN]). A static load of 100 N was applied to the basal ridge surface of the abutment at a 45‐degree oblique angle to the long axis of the implant. Both stress distribution in peri‐implant bone and abutment micromovement in the SA and TA models were analyzed. Results: Compressive stress concentrated on labial cortical bone and tensile stress on the palatal side in the EM and on the labial side in the IM. There was no difference in maximum principal stress distribution for SA and TA models. Tensile stress concentration was not apparent on labial cortical bone in the PS model (versus IM). Maximum principal stress concentrated more on peri‐implant bone in the RN than in the TA model. The TA model exhibited less abutment micromovement than the SA model. Conclusion: This study reveals the effects of the design of specific components on peri‐implant bone stress and abutment displacement after implant‐supported single restoration in the anterior maxilla.  相似文献   
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