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find Keyword "钙化" 39 results
  • A Brief Analysis of Formation Mechanism and Related Issues of Psammoma Body in Human Tumors .

    Objective To understand the latest research developments of the formation mechanism of psammoma body in human tumors and related issues. Methods Related domestic and foreign literatures were widely referred, analyzed, and reviewed. Results Psammoma body is unique pathological calcification in some tumors, which is arranged in concentric, laminar circles microscopically. Psammoma body is commonly seen in thyroid papillary carcinoma, meningiomas, ovarian serous papillary carcinoma, and so on. Conclusions Although arranged in concentric, laminar circles microscopically in tumor, the formation process of psammoma body is not entirely the same in different tumors. A comprehensive and objective understanding of psammoma body would be useful in cancer diagnosis and treatment.

    Release date:2016-09-08 10:50 Export PDF Favorites Scan
  • 血液透析患者顽固性皮肤溃疡伴下肢动脉重度闭塞两例

    Release date:2021-08-24 05:14 Export PDF Favorites Scan
  • Detection of microcalcification clusters regions in mammograms combining discriminative deep belief networks

    In order to overcome the shortcomings of high false positive rate and poor generalization in the detection of microcalcification clusters regions, this paper proposes a method combining discriminative deep belief networks (DDBNs) to automatically and quickly locate the regions of microcalcification clusters in mammograms. Firstly, the breast region was extracted and enhanced, and the enhanced breast region was segmented to overlapped sub-blocks. Then the sub-block was subjected to wavelet filtering. After that, DDBNs model for breast sub-block feature extraction and classification was constructed, and the pre-trained DDBNs was converted to deep neural networks (DNN) using a softmax classifier, and the network is fine-tuned by back propagation. Finally, the undetected mammogram was inputted to complete the location of suspicious lesions. By experimentally verifying 105 mammograms with microcalcifications from the Digital Database for Screening Mammography (DDSM), the method obtained a true positive rate of 99.45% and a false positive rate of 1.89%, and it only took about 16 s to detect a 2 888 × 4 680 image. The experimental results showed that the algorithm of this paper effectively reduced the false positive rate while ensuring a high positive rate. The detection of calcification clusters was highly consistent with expert marks, which provides a new research idea for the automatic detection of microcalcification clusters area in mammograms.

    Release date:2021-06-18 04:50 Export PDF Favorites Scan
  • RESEARCH PROGRESS OF CALCIFIED CARTILAGE ZONE

    To review the structure and function of the calcified cartilage zone and its role in the pathogenesis of osteoarthritis (OA). Methods Recent l iterature about calcified zone was reviewed and analyzed in terms of architecture, composition, biomechanics, and biological function. Results Calcified zone has particular structure and material properties, and functions as a semi permeable membrane; chondrocytes in the calcified zone retain some characteristics of growth plate cells, which play a crucial role in cartilage function maintenance and pathogenesis of OA. Therefore, reconstructionof the calcified zone at osteochondral conjunction has become one of the hot research in the fields of interface tissue engineering. Conclusion It is necessary to pay more attention to calcified cartilage zone, which is important for both the treatment of OA and the preparation of tissue engineered osteochondral composite.

    Release date:2016-08-31 05:42 Export PDF Favorites Scan
  • A case of perivalvular leakage and attempt of closure operation after transcatheter aortic valve replacement

    This paper reported a 75-year-old female patient. She was admitted to our hospital for “repeated chest pain, shortness of breath for more than 5 years, and syncope 3 times”. The CT scan of the patient showed severe aortic valve stenosis, bicuspid valve, and severe calcification; then she underwent transcatheter aortic valve replacement in our hospital. After the prosthesis was implanted, there was a significant paravalvular leak. Considering the triangular area formed between the calcified clumps, the valve was not fully dilated. Paravalvular leak closure was performed during the operation, attempted through the valve stent mesh to closuring. A rare incarceration of the transmitter occurred. An attempt was made to pull out the incarcerated transmitter through a pull-up technique, which resulted in the prosthesis prolapse. The patient was eventually transferred to surgery aortic valve replacement.

    Release date:2020-05-26 02:34 Export PDF Favorites Scan
  • Analysis of Mammographic Characteristics of Calcification in Breast Tumor Without Mass

    ObjectiveTo investigate the X-ray diagnostic significance of calcification of the breast tumor without mass. MethodsMammograms of 90 cases of breast tumor without mass confirmed pathologically were retrospectively analyzed. There were 55 cases confirmed benign breast tumor, and the rest cases were breast cancer. The shape, distribution, total number, location of calcifications in the breast, and asymmetric dense of the breast were recorded and watched. Results①The X-ray findings of calcification in benign breast tumors always presented as coarse granular (31), scattered shape (35) with small number, less with the asymmetric dense of the breast (7), and the change of side with axillary lymph node (2). ②Meanwhile, fine sand-like (32), showing the cluster-like distribution (24) with larger number, with the asymmetric dense of the breast (24) and the change of side with axillary lymph node (10). Both of the differences of the calcifications (the shape, the distribution, and the total number) were statistically significant (Plt;0.05). ConclusionsThe calcifications of benign and malignant breast tumors have their unique X-ray characteristics. And there is a great value in differentiating early benign and malignant breast tumor.

    Release date:2016-09-08 10:42 Export PDF Favorites Scan
  • Single-center retrospective analysis of 125 donor hearts from brain death donation and to explore the use of marginal donor hearts

    ObjectiveTo analyze the assessment and maintenance of 125 donor hearts from brain death donation and explore the use of marginal donor hearts.MethodsA retrospective analysis was conducted on the evaluation, maintenance, operation and follow-up results of 125 donor hearts from April 2016 to August 2019. There were 98 males and 27 females at age of 6-50 (36.0±2.4) years.ResultsTwelve donor hearts were discarded due to unqualified evaluation after heart harvest. 113 patients of heart transplantation were performed with a double lumen venous anastomosis manner. The mean time of cold ischemia was 220.1±6.7 min. Four patients died within 30 days after operation. Postoperative right ventricular assist circulation was performed in 4 patients, intra-aortic balloon counterattack (IABP) in 12 patients and extracorporeal membrane oxygenation (ECMO) in 12 patients. Marginal donors included 15 hepatitis B antigen positive donor hearts, 2 tricuspid regurgitation, 1 mitral regurgitation, 5 coronary calcification, 4 myocardial stunning and 2 severe weight mismatch. The results of follow-up (2 years) after marginal donor heart transplantation were satisfactory.ConclusionImproving the assessment and maintenance of donor hearts can improve the utilization rate of the heart, and the marginal donor heart transplantation needs long-term follow-up.

    Release date:2019-10-12 01:36 Export PDF Favorites Scan
  • 关节镜下治疗肩袖钙化性肌腱炎的近期疗效

    目的 总结关节镜下治疗肩袖钙化性肌腱炎的近期疗效。 方法2007年7月-2011年6月,采用关节镜下彻底清除钙化灶治疗20例肩袖钙化性肌腱炎患者。男6例,女14例;年龄38~62岁,平均48.2岁。肩关节疼痛3~12个月,平均6.8个月;肩关节功能均严重受限。钙化灶位于肩袖表面6例,冈上肌腱内8例,冈上、冈下肌腱交界处4例,冈下肌腱内2例。 结果术后患者切口均Ⅰ期愈合,无手术相关并发症发生。患者均获随访,随访时间6~24 个月,平均16个月。术后6个月复查X线片示钙化灶均消失。术后患者运动或静息时关节疼痛均较术前显著改善,术后1、4周及6个月时关节疼痛评分、关节活动度评分以及关节功能评分与术前比较,差异均有统计学意义(P lt; 0.05)。 结论关节镜下治疗肩袖钙化性肌腱炎可彻底清除钙化灶,恢复肩关节活动度,缓解关节疼痛,近期疗效较好。

    Release date:2016-08-31 04:06 Export PDF Favorites Scan
  • HISTOMORPHOMETRIC ANALYSIS OF ARTICULAR CARTILAGE AND SUBCHONDRAL BONE FROM PRIMARY OSTEOARTHRITIC KNEES

    To investigate the pathologic characteristics of the articular cartilage and subchondral bone from osteoarthritic knees, and to compare the structural parameters of articular cartilage and subchondral bone between the medial and lateral tibial plateau, so as to determine the role of calcified zone and subchondral bone in the pathogenesis of osteoarthritis (OA). Methods The tibial plateaus were taken from 30 patients undergoing total knee arthroplasty between October 2009 and May 2011. The subjects included 11 males and 19 females with an average age of 65.1 years (range, 55-78years). The mean disease duration was 16.6 years (range, 10-25 years); the mean varus angle of the diseased knee was 9.3° (range, 1-23°). After gross observation, the cartilage-bone samples were taken out from the most weight-bearing regions in the internal areas of the medial and lateral plateaus. The decalcified paraffin-embedded sections were prepared and stained with HE and Safranin O/fast green for cartilage assessment (Mankin score), staging, and bone histomorphometry; the pathologic features of the cartilage and subchondral bone were also observed. The thickness of total articular cartilage (TAC), articular calcified cartilage (ACC), subchondral bone plate (SCP), and the trabecular bone volume (BV/TV) were measured by Image Pro Plus 6.0 imaging system, then the ratio of ACC/TAC was calculated. Results Macroscopic results showed that articular cartilage degeneration was more severe in the medial plateau than in the lateral plateau; Mankin score of the medial plateau (12.4 ± 1.1) was significantly higher than that of the lateral plateau (8.3 ± 1.6) (t=12.173, P=0.000). In the 60 samples, 14 samples were at stage I, characterisd by fissures within the superficial zone, dupl icated tidemark, and thickend subchondral bone; 19 samples were at stage II, characterisd by fissures extending into the deep zone, multiple subchondral bone resorption pits, and obviously thickend subchondral bone; and 27 samples were at stage III, characterisd by full-thickness cartilage defects, endochondral ossification, and eburnated subchondral bone. The bone histomorphometric study showed that TAC thickness of the medial plateau was significantly lower than that of the lateral plateau (P lt; 0.05); the ratios of ACC/TAC, BV/TV, and SCP thickness of the medial plateau were significantly higher than those of the lateral plateau (P lt; 0.05). However, there was no significantdifference in the ACC thickness between the medial and lateral plateaus (P gt; 0.05). Conclusion The calcified zone andsubchondral bone may play an important role in the initiation and progression of OA.

    Release date:2016-08-31 05:42 Export PDF Favorites Scan
  • STUDY ON SHAPE AND STRUCTURE OF CALCIFIED CARTILAGE ZONE IN NORMAL HUMAN KNEE JOINT

    To explore the shape and structure of calcified cartilage zone and its interface between the non-calcified articular cartilage and subchondral bone plate. Methods The normal human condyles of femur (n=20) were obtained from the tissue bank donated by the residents, 10 males and 10 females, aged 17-45 years. The longitudinal and transverse paraffin sections were prepared by the routine method. The shape and structure of calcified cartilage zone were observed with theSafranin O/fast green and von kossa stain method. The interface conjunction among zones of cartilage was researched by SEM and the 3D structural model was establ ished by serial sections and model ing technique. Results Articular bone-cartilage safranin O/fast green staining showed that cartilage was stained red and subchondral bone was stained blue. The calcified cartilage zone was located between the tidemark and cement l ine. Von kossa staining showed that calcified cartilage zone was stained black and sharpness of structure border. Upper interface gomphosised tightly with the non-calcified cartilage by the wave shaped tidemark and lower interface anchored tightly with the subchondral bone by the uneven comb shaped cement l ine. The noncalcified cartilage zone was interlocked tightly in the manner of “ravine-engomphosis” by the calcified cartilage zone as observed under SEM, and the subchondral bone was anchored tightly in the manner of “comb-anchor” by the in the calcified cartilage zone 3D reconstruction model. Conclusion The calcified cartilage zone is an important structure in the articular cartilage. The articular cartilage is fixed firmly into subchondral bone plate by the distinctive conjunct interfaces of calcified cartilage zone.

    Release date:2016-09-01 09:12 Export PDF Favorites Scan
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