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991.
992.
Skeletal Status in Children,Adolescents and Young Adults with End-Stage Renal Failure Treated with Hemo- or Peritoneal Dialysis 总被引:4,自引:0,他引:4
W. Pluskiewicz P. Adamczyk B. Drozdzowska K. Szprynger M. Szczepanska Z. Halaba D. Karasek 《Osteoporosis international》2002,13(5):353-357
The skeletal status in 30 children, adolescents and young adults (18 females, 12 males) with end-stage renal failure (ESRF)
aged 9-23 years (mean 15.8 ± 3.6 years) was evaluated using measurements of bone mineral density (BMD, g/cm2) at the spine and total body (TB) (Lunar DPX-L, USA), quantitative ultrasound (QUS) of the hand phalanges (DBM Sonic 1200,
IGEA, Italy) and laboratory investigations (parathyroid hormone, serum total and ionized calcium, serum phosphate). Eleven
subjects were treated with hemodialysis and 19 with peritoneal dialysis. The mean value of the amplitude-dependent speed of
sound (Ad-SoS, m/s) measured by QUS was significantly decreased in comparison with the value obtained in a group of 686 age-matched
controls (1942 ± 74 m/s vs 2050 ± 77 m/s, p<0.0001). BMD measurements were also decreased in comparison with mean values for the healthy population (Z-scores for spine −1.47, and for TB −1.53). Duration of dialysis correlated significantly with spine-BMD, TB-BMD and Ad-SoS
(r=−0.37, r = −0.45, r=−0.55, respectively, p<0.05), while duration of ESRF did not have such an influence. Laboratory investigations did not correlate with skeletal parameters.
Ad-SoS correlated significantly with spine-BMD (r= 0.45, p<0.05) and TB-BMD (r= 0.56, p<0.01). Both QUS and BMD values correlated significantly with Tanner stages (r ranged from 0.59 to 0.69, p<0.001) and did not increase with age except for correlation between age and TB-BMD. In conclusion, skeletal status in the
population studied is strongly affected by ESRF. Both QUS and BMD measurements show an ability to express skeletal changes
in a similar manner, though the QUS parameter seems to be more sensitive at revealing changes due to renal failure.
Received: 12 July 2001 / Accepted: 8 November 2001 相似文献
993.
BACKGROUND: We have previously demonstrated that the proteolytic activity of Der p 1 selectively cleaves human CD25, the 55 kDa alpha subunit of the IL-2 receptor. As a result of cleavage of surface CD25, peripheral blood T cells produce less IFN-gamma and more IL-4, thereby leading to progressive polarization of the T cells towards a Th2 cytokine profile. Therefore, these observations underline the potential role of the proteolytic activity of Der p 1 in creating a microenvironment conducive for IgE synthesis. OBJECTIVE: To study the effect of T cells that have been conditioned by the proteolytic activity of Der p 1 on IgE synthesis by B cells. METHODS: We have examined this concept in experiments whereby T cells that have been exposed to either proteolytically active or inactive Der p 1 were cocultured with autologous B cells and IgE antibody synthesis was monitored. RESULTS: Here we demonstrate for the first time that coculturing T cells that have been in contact with proteolytically active Der p 1 with autologous B cells leads to augmentation of IgE antibody responses. CONCLUSIONS: The proteolytic activity of Der p 1 conditions human T cells, which then become empowered to trigger enhanced IgE synthesis by B cells. 相似文献
994.
The use of biochemical markers of bone turnover has been advocated to improve follow-up of women receiving antiresorptive
therapies for osteoporosis, but this strategy is not yet supported by trials showing it improves effectiveness of treatments.
To explore the potential value of markers of bone turnover to monitor antiresorptive treatments of osteoporosis, we conducted
a decision analysis using a decision tree and Markov modeling. We have compared two strategies: treatment of a woman without
specific monitoring; and treatment of this woman with measurement of a serum marker of bone resorption after 3 months of treatment,
with change of treatment if response to treatment assessed by this marker was not satisfactory. The base case is the treatment
of a 60-year-old osteoporotic woman with a total hip T-score of −3, using a second generation bisphosphonate during 5 years. We found that follow-up produced slightly greater quality
adjusted life years (QALYs) than no follow-up (8.1560 vs 8.1532, i.e. a one day difference). In a two-way sensitivity analysis,
the follow-up option produced higher QALYs so long as adherence rate with follow-up was equal or superior to the proportion
of women who adhered without follow-up. For example, if the proportion of women adherent to treatment was increased from 50%
to 60% by follow-up, then the expected value of the follow-up branch was increased from 8.1560 QALYs to 8.1800 QALYs (i.e.
a difference of 9 days). In addition, the higher the non-response rate, the greater the benefit from monitoring with a biochemical
marker. In conclusion, our decision analysis model suggests that follow-up of osteoporotic women treated with a second generation
bisphosphonate during a 5-year period using an early measurement of a serum marker of bone resorption may increase effectiveness
of the treatment on quality of life, but the effect is very small. So, the use of follow-up measures of bone turnover may
be based on patient and physician preferences.
Received: 6 July 2001 / Accepted: 1 April 2002 相似文献
995.
996.
997.
乙型和丙型肝炎病毒血清学标志与原发性肝癌关系的研究 总被引:4,自引:0,他引:4
目的:研究原发性肝齐(PHC)病人中乙型肝炎病毒(HBV)和丙型肝炎病毒(HCV)血清学标志的分布状况。方法:选择全市40家医院收治住院确诊PHC患者100例,用ELISA法进行HBsAg、抗-HBs、HBeAg、抗-HBe和抗-HBc和抗-HCV检测。结果:PHC组HBV和抗-HCV的感染率分别为89.0%和8.0%,明显高于对照组(P<0.001),两者的ARP(归因危险度百分比)分别为93.0%和88.0%。HBV血清学标志在PHC的分布较高的是HBsAg、抗-HBc和HBsAg、HBeAg、抗-HBc组合。协同作用分析结果显示HBsAg、抗-HCV同时阳性者的OR值为46.28,较单一指标阳性的OR为高,也高于两者单独阳性的OR值之和。结论:HBV和HCV感染均是PHC发生的主要病原学因素。HBV是肝癌发生的主要因素。 相似文献
998.
目的 通过对24例阴道肿瘤患者的B超声像图分析,总结B超诊断阴道肿瘤的方法。方法 收集24例1995~2002年,我院门诊及住院患者的病史资料及声像图,结合病理结果分析声像图特征,并与病理加以对照。结果 24例患者声像图表现为囊性、实质性、囊实性肿瘤。结论 通过对声像图的分析,探讨了B超诊断阴道肿瘤的可行性、声像图特征及该方法的局限性。 相似文献
999.
Salim H. Khalil Mohammed H. Qari John M. Jackson Robert Haywood Pyle Hassan El-Solh Abdallah Al-Nasser 《Leukemia research》1994,18(12):881-883
Geographical variations in the incidence of disease are of considerable theoretical and practical importance. It has been claimed that the distribution of acute lymphoblastic leukemia (ALL) phenotypes in Saudi Arabia is different from that recorded in the Western literature. One hundred and twelve (112) patients under 15 years of age, diagnosed as ALL between January 1992 and May 1994 had immunophenotypes performed on their blast cells. Common ALL (cALL) together with pre-B-ALL, formed 86.5% of the total; B-cell 3%, T-cell 6% and null cell 4.5%. These figures are not significantly different from the Western literature. A previous claim from this institution in 1990, that both null and B-cell ALL were significantly increased compared with elsewhere, is not supported by the present figures. Age and sex distribution, and FAB classification, L1 77%, L2 20% and L3 3%, were also of the same order as described elsewhere and, in particular, there was no increase in the frequency of L3 subtype. 相似文献
1000.
目的观察内毒素休克大鼠血浆及主要脏器核因子(NF)κB活化规律及其对生物蝶呤(BH4)和一氧化氮(NO)表达水平的影响,探讨内毒素休克时NF-κB信号通路对BH4诱生NO的分子调控机制及其与多器官功能损害的关系。方法将47只大鼠按表格随机法分为正常组(8只)、内毒素/脂多糖(LPS)组(24只,每观察时相点8只,均同时注射LPS制成休克模型)和拮抗组[15只,每观察时相点5只,均同时注射LPS并以吡咯烷二硫代氨基甲酸盐(PDTC)拮抗]。休克及拮抗组于注射LPS后2、6、12 h观察,并与正常组同法处死,无菌留取大鼠血标本及肝、肺、肾组织,测定组织中NF-κB活性和三磷酸鸟苷环水解酶Ⅰ(GTP-CHⅠ)和诱导型一氧化氮合酶(iNOS)mRNA表达水平、血浆和组织中的BH4含量及NO水平、肝脏和肾脏功能指标、肺组织髓过氧化物酶活性。结果与正常组(例如肺组织中NF-κB活性为26±6)比较,LPS组大鼠组织中NF-κB迅速活化(P<0.01),并于注射后2 h达峰值(肺组织中为291±44);LPS组各组织中GTP-CHⅠ和iNOS mRNA表达、BH4和NO水平也较正常组明显升高(P<0.05或0.01),至伤后12 h仍持续较高水平。此外,该组相应器官功能均受到不同程度的损害。应用PDTC的拮抗组大鼠各组织中NF-κB活性均较LPS组有所降低,GTP-CHⅠ、iNOS mRNA表达及BH4、NO水平显著受抑,肝、肺、肾功能明显改善。结论内毒素休克时机体内NF-κB通路高度活化,并对BH4/NO系统具有明显调节效应;可通过下调BH4介导的iNOS的过度活化抑制NF-κB信号途径,从而减轻组织炎性反应,对机体脏器功能起到保护作用。 相似文献