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51.
Tartrate-resistant acid phosphatase (TRAcP) is used as a marker for osteoclasts, which are believed to be derived from phagocytic cells or phagocyte stem cell precursors. To further investigate the relationship between monocytic phagocytes and osteoclasts, acid phosphatase (AcP) activity was measured by three different techniques in human peripheral blood monocytes, monocyte-derived macrophages, and the U937 cell line. We found that cytochemistry and gel electrophoresis led to similar results, but that the colorimetric assay was inconsistent. Normal human peripheral monocytes expressed both tartrate-sensitive and -resistant AcP. In culture these cells formed polykaryons and expressed TRAcP activity that was further identified as an isoenzyme associated with bone tissue. In contrast, the U937 cells did not express TRAcP activity as measured by gel electrophoresis. Both U937 cells and monocytes possess material that interferes with interpretation of the colorimetric assay of AcP. The presence of TRAcP in monocyte-derived macrophages further supports the relationship between phagocytic cells and bone osteoclasts. 相似文献
52.
P. K. S. Chan K.-W. Chik C.-K. Li N. L. S. Tang M. S. K. Ming J. L. K. Cheung K.-C. Ng P. M. P. Yuen & A. F. Cheng 《Journal of viral hepatitis》2001,8(4):304-309
Peripheral blood mononuclear cells (PBMC), plasma, saliva and urine samples were collected from 50 thalassaemic patients for TT virus (TTV) detection by two sets of PCR. The set B nested PCR was more sensitive than the widely used NG hemi-nested PCR with TTV positive rates ≈ PBMC: 98% vs. 70%; plasma: 92% vs. 66%; saliva: 62% vs. 22%; urine: 22% vs. 6%. All 50 patients had TTV detected in one or more specimens, with 16% of patients being positive in all four specimen types: 40% positive in PBMC, plasma and saliva; 30% positive in PBMC and plasma. In 82 NG hemi-nested PCR-positive samples TTV genotype was identified, 68.3% had a single genotype, 25.6% had multiple genotypes and 6.1% were uncharacterized. The positive rates for genotypes by specimen were: G1 (36/82), G2 (49/82), G3 (2/82), G4 (7/82), G5 (1/82) and G6 (3/82). Among the 42 patients for whom the genotype was examined, 42.9% had single-type infection, 45.2% had co-infections and 11.9% had uncharacterized genotypes. Sixteen of them had TTV detected both in PBMC and plasma with seven having identical genotypes in both samples. Eight patients had TTV detected in PBMC, plasma and saliva; two of them harboured identical genotypes in all three samples. The results indicate that, apart from hepatocytes, PBMC is a major cell type for TTV infection occurs. Shedding of TTV in urine and saliva is common and may have a significant role in nonblood-borne transmission among the general population. TTV-infected patients often harbour multiple genotypes suggesting infection with one genotype does not necessarily confer protection against the others. No correlation between TTV infection and liver dysfunction was observed. 相似文献
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54.
A multiple regression-based statistical model capable of quantitatively comparing two or more sonographic parameters for the effects of gestational age, variation in fetal growth and error in sonographic measurement is presented and then used to compare the biparietal diameter and femur length as estimators of gestational age in late pregnancy. A total of 311 patients were studied between 24 and 42 weeks' gestation. Variation in fetal growth was expressed as the birth weight percentile for gestational age. Biparietal diameter and femur length correlated equally well with gestational age. However, the biparietal diameter was more than twice as sensitive as the femur length to variation in fetal growth. Femur length had a larger error associated with its measurement. These results suggest that the biparietal diameter and femur length in late pregnancy are equal estimators of gestational age; that the femur length is a more stable estimator of gestational age when fetal growth deviates from normal; and that the femur length is technically more difficult to obtain. 相似文献
55.
Maggie KM Ma Helen KW Law Kin Sun Tse Kwok Wah Chan Gary CW Chan Desmond YH Yap Maggie MY Mok Lorraine PY Kwan Sydney CW Tang Bo Ying Choy Tak Mao Chan 《International journal of urology》2018,25(5):450-455
Objectives
To evaluate the use of shear wave elastography in assessment of kidney allograft tubulointerstitial fibrosis.Methods
Shear wave elastography assessment was carried out by two independent operators in kidney transplant recipients who underwent allograft biopsy for clinical indications (i.e. rising creatinine >15% or proteinuria >1 g/day). Allograft biopsies were interpreted by the same pathologist according to the 2013 Banff Classification.Results
A total of 40 elastography scans were carried out (median creatinine 172.5 μmol/L [interquartile range 133.8–281.8 μmol/L]). Median tissue stiffness at the cortex (22.6 kPa [interquartile range 18.8–25.7 kPa] vs 22.3 kPa [interquartile range 19.0–26.5 kPa], P = 0.70) and medulla (15.0 kPa [interquartile range 13.7–18.0 kPa] vs 15.6 kPa [interquartile range 14.4–18.2 kPa]) showed no significant differences between the two observers. Interobserver agreement was satisfactory (intraclass correlation coefficient of the cortex 0.84, 95% CI 0.70–0.92 and intraclass correlation coefficient of the medulla 0.88, 95% CI 0.78–0.94). The areas under the receiver operating characteristic curves for detection of tubulointerstitial fibrosis were estimated to be 0.75 (95% CI 0.61–0.89), 0.85 (95% CI 0.75–0.95) and 0.65 (95% CI 0.53–0.78) for cortical, medullary tissue stiffness and serum creatinine, respectively.Conclusions
Shear wave elastography can be used as a non‐invasive tool to evaluate kidney allograft fibrosis with reasonable interobserver agreement and superior test performance to serum creatinine in detecting early tubulointerstitial fibrosis. 相似文献56.
SG Divers ; K Kannan ; RM Stewart ; KW Betzing ; D Dempsey ; M Fukuda ; R Chervenak ; RF Holcombe 《Transfusion》1995,35(4):292-297
BACKGROUND: Platelets become activated during storage, which results in secretion of granules, vesiculation of microparticles, secretion of protein, and a number of other biochemical and morphologic processes that decrease the utility of platelet concentrates stored for transfusion. STUDY DESIGN AND METHODS: To evaluate the quality of stored platelet concentrates, the cell surface expression of specific activation-dependent antigens (CD62 and lysosome-associated membrane proteins 1 and 2 [LAMP-1, LAMP-2]) on platelets stored in a hospital blood bank over a 7-day period was examined. Relative microparticle counts and the expression of CD62 by microparticles, as well as platelet concentrate supernatant levels of soluble CD62, were determined. RESULTS: The percentage of platelets expressing CD62 increased significantly from Day 1 to Day 5 (p < 0.05) of storage; the mean fluorescence values for CD62 did not. In contrast, the mean fluorescence values of LAMP-1 and LAMP-2 rose significantly (p < 0.01 and p < 0.05, respectively) between Days 1 and 5. Significant declines in CD62, LAMP-1, and LAMP-2 percent expression and mean fluorescence were seen on Day 6 of storage (p < 0.001). Microparticle numbers increased significantly during storage and correlated with levels of CD62 protein (free and membrane-bound) (r = 0.95 vs. Day 2, p < 0.05; r = 0.88 vs. Day 5, p < 0.05). CONCLUSION: Flow cytometric evaluations of the expression of cell surface CD62, LAMP-1, and LAMP-2 are complementary tests that, especially when used in conjunction with the quantitation of CD62 protein, provided a simple and effective means of evaluating the quality of platelet concentrates stored for transfusion. 相似文献
57.
骺板软骨细胞的体外培养及鉴定 总被引:2,自引:0,他引:2
目的:建立体外培养及鉴定骺板软骨细胞的方法。方法:实验于2005-03/2006-05在苏州大学附属儿童医院骨科实验室完成。选用3只生后14~28d的新西兰幼兔,空气栓塞处死,暴露股骨下端和胫骨上端,分别取2处的骺板组织,将其剪切成1~3mm3的小块,经胰蛋白酶消化,接种于含150g/L牛血清的1640培养基中,饱和湿度培养,传代。①细胞接种后3h在倒置显微镜下观察细胞生长情况,见细胞贴壁后每天观察2次。②第2代细胞达到80%~90%左右汇合时采用常规苏木精-伊红染色,光镜观察细胞爬片情况。③第3代细胞爬片至细胞达到80~90%左右汇合时,采用苏木素染色3min,3%亮绿染色5min,蕃红花“O”染色5min,光镜观察细胞产生蛋白聚糖情况。④采用PCR检测细胞Ⅱ型胶原的表达。⑤采用四唑盐MTT比色法检测细胞活性。结果:①骺软骨细胞刚接种后呈大小不等之圆形悬浮于培养液中,3h后见大部分细胞贴壁,24h后贴壁细胞呈短梭形、圆形、三角形和不规则形,见细胞分裂相。48h后见细胞伸展明显,细胞分裂相每高倍镜视野可见多个。经隔日换液细胞生长至第5天,细胞呈聚集生长,达到汇合状态,将细胞传代。接种后第1代细胞2d后呈梭形,培养4d传至第2代,第2代细胞长满瓶底后,90%呈胞膜较厚的圆形,10%为梭形,第3代、第4代亦如此。传至第5代见肥大细胞增多,细胞松散,折光性减弱,呈凋亡状态。②细胞爬片后观察骺软骨细胞形态以梭形居多,同时也有圆形、三角形和不规则形。可见细胞分裂及细胞中的分泌小泡。③见细胞呈红色,无绿色,证明蕃红花“O”-亮绿染色阳性,显示所培养的细胞可以分泌蛋白聚糖。④PCR检测术所养细胞含有Ⅱ型胶原,电泳带在440bp上。⑤四唑盐MTT比色法检测显示,第3代骺软骨细胞的生长曲线近似倒“S”形,在第4,5,6天细胞呈对数生长,约在7,8,9,10d达平台期,至第12天细胞出现生长抑制。结论:建立了骺板软骨细胞的体外培养方法,并证实所培养出的细胞分泌蛋白聚糖和Ⅱ型胶原,具有软骨细胞的共同特点。 相似文献
58.
See Ching Chan Chung Mau Lo Barbara H. Chik Lorraine C. Chow Sheung Tat Fan 《Clinical transplantation》2010,24(3):410-414
Chan SC, Lo CM, Chik BH, Chow LC, Fan ST. Flowmetry‐based portal inflow manipulation for a small‐for‐size liver graft in a recipient with spontaneous splenorenal shunt.Clin Transplant 2010: 24: 410–414. © 2009 John Wiley & Sons A/S. Abstract: We report a case of living donor liver transplantation using a small‐for‐size graft (SFSG) with graft to estimated standard liver volume of only 28% in a recipient with spontaneous splenorenal shunt and demonstrate the value of intraoperative ultrasonic flowmetry. Despite an SFSG, the graft was underperfused. This was recognized by flowmetry and was rectified by ligation of the splenorenal shunt. 相似文献
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60.