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121.
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123.
Accuracy and reproducibility of urea recirculation in detecting haemodialysis access stenosis 总被引:1,自引:1,他引:0
Paulson W; Gadallah M; Bieber B; Altman S; Birk C; Work J 《Nephrology, dialysis, transplantation》1998,13(1):118-124
Background: There is wide disagreement among studies
that have evaluated the accuracy of urea recirculation (UR) in detecting
vascular access stenosis. The 3-site method (UR3) has been discredited and
replaced by the 2-site method (UR2), but few studies have evaluated UR2.
Methods: We compared the accuracies of UR2 and UR3 in
detecting stenosis in 59 haemodialysis patients during a 12-month period.
All patients were studied without regard to clinical suspicion of stenosis.
Stenosis (⩾50% luminal narrowing) was diagnosed by duplex
ultrasound and confirmed by angiography. The reproducibility of UR2 was
determined by computing its total standard deviation (SDTOT) from
measurements during three dialysis sessions over a 15-day period.
Results: Stenosis was found in 32% of 124 access
studies (mean luminal narrowing=58%, range=50-83%). The mean UR values of
stenotic accesses were only slightly higher than nonstenotic accesses for
both UR2 (7.6% vs 2.9%, P <0.01) and UR3 (13.1%
vs 11.2%, P=0.22). An increase in blood pump speed
from 300 to 425 ml/min did not improve detection of stenosis by UR2. There
were no UR thresholds that cold adequately separate the presence of
stenosis from its absence. The SDTOT of UR2 was 3.8%, indicating that a
patient's UR2 measurement may vary over a range of 16%
(±2SDTOT=±8%). Conclusion:
Stenosis of the haemodialysis access does not predictably cause
recirculation, and the reproducibility of the UR2 measurement is poor. 相似文献
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125.
Benacerraf BR; Greene MF; Saltzman DH; Barss VA; Penso CA; Nadel AS; Heffner LJ; Stryker JM; Sandstrom MM; Frigoletto FD Jr 《Radiology》1988,169(3):709-710
Early amniocentesis at 11-14 weeks gestation was evaluated in 100 consecutive patients to see how this technique compares with later amniocentesis. There were no complications as a consequence of the procedure or related pregnancy losses of chromosomally normal fetuses. Samples obtained from three (3%) patients showed insufficient cell growth; two of these patients elected a repeat procedure, which yielded a normal karyotype in each case. There were five abnormal karyotypes, one of which was a culture artifact; in the latter case, repeat amniocentesis at 15 weeks yielded a normal result. Of the 95 pregnancies with normal karyotypes, 94 were progressing normally at follow-up, and one patient elected pregnancy termination because of maternal indications. It appears that early amniocentesis may be an attractive alternative to traditional amniocentesis, in that it provides results at an earlier gestational age and may avoid certain disadvantages of chorionic villus sampling. 相似文献
126.
Nabila Yousef Abdelhalim Mohammed Hany Shehata Hanan Nabih Gadallah Walaa Mohamed Sayed Aref Ali Othman 《Acta histochemica》2018,120(5):490-503
Diabetes mellitus (DM) is a chronic metabolic disease in which the body fails to produce enough insulin or increased tissue resistance to insulin. The diabetes may have profound effects on placental development and function. This study was designed to detect the placental changes in pregnancy associated with DM comparing these changes with normal placenta. The study was carried out on sixty full-term placentae; divided into three equal groups; control group (group I): placentae of normal pregnancy, uncontrolled diabetes (group II): placentae from pregnant women whose blood glucose is poorly controlled during pregnancy. Controlled diabetes (group III): includes placentae from diabetic women whose blood glucose is controlled during pregnancy. The placentae from group II tend to be heavier and exhibited immaturity of villi, villous edema, fibrosis, excessive syncytial knots formation and infarctions. In addition to, fibrinoid necrosis, increased thickness of vasculosyncytial membrane, syncytial basement membrane, microvillous abnormalities and vascular endothelial changes were demonstrated. The syncytial multivesicular knots were present in placentae of group II. The nuclei within these syncytial knots display condensed chromatin, either dispersed throughout the nucleus or in the form of dense peripheral clumps with and numerous cytoplasmic vacuoles. The syncytial basement membrane showed focal areas of increase in its thickness and irregularity. Villous cytotrophoblasts showed increased number and activity in the form of numerous secretory granules, abundant dilated RER, larger distorted mitochondria. Villous vessels showed various degrees of abnormalities in the form of endothelial cell enlargement, folding, thickening and protrusion of their luminal surfaces into vascular lumen making it narrower in caliber. In placentae of group III, most of these abnormalities decreased. In most of placentae of group III, the VSM appeared nearly normal in thickness and showed nearly normal composition of one layer of syncytiotrophoblastic cells, one layer of smooth, regular capillary endothelium and the space between them. Mild microvillous abnormalities were noted in few placentae as they appeared short and blunted with mild decrease in their number per micron. The electron picture of syncytial knots appeared nearly normal containing aggregations of small, condensed hyperchromatic nuclei, minimal vacuoles could be seen in the cytoplasm of syncytial knots. Syncytial basement membrane appeared regular and nearly normal in its thickness and composition coming in direct contact with fetal blood capillaries but mild abnormalities were noted in the basement membrane in few placentae as increased its thickness and deposition of fibers or fibrinoid. Regarding cytotrophoblasts in the terminal villi of placentae with controlled diabetes, these cells appeared nearly normal. They were scattered beneath the syncytium and were active containing mitochondria, rough endoplasmic reticulum, free ribosomes and a large nucleus with fine dispersed chromatin. The vascular ultrastructural pattern in terminal villi of placentae of this group showed no significant abnormalities and was normally distributed in the villous tree. The luminal surface of the vascular endothelium appeared regular smooth in the majority of placentae of this group. The endothelial cells appeared connected to each other with tight junctions. It could be concluded that whether if long-term diabetes is controlled or not, placentae of diabetic mother showed a variety of significant histological structural changes seen more frequently than in the placentae of pregnant women without diabetes. 相似文献
127.
NL Hoenderdos NAM Rosema DE Slot MF Timmerman U van der Velden GA van der Weijden 《International journal of dental hygiene》2009,7(4):294-298
Abstract: Aim: To evaluate the inhibition of plaque growth by an experimental mouthrinse (BioXyl®) based on hydrogen peroxide/glycerol. Design: It was a double‐blind, randomized study involving 40 volunteers in good general health. At the start of the trial, all participants received a dental prophylaxis to remove all plaque deposits. During the next 3 days subjects refrained from any mechanical oral hygiene procedure, except for the allocated mouthrinse being either the hydrogen peroxide (H2O2; 0.013% H2O2/0.004% glycerol) or the placebo without H2O2. At the third day of appointment, plaque levels were assessed at six sites per tooth. Results: The test group had a mean overall plaque score of 2.66 and the placebo group of 2.70. The difference in plaque scores between the two groups was not statistically significant. Conclusions: The results of this pilot study showed that there was no statistically significant difference between the H2O2/glycerol group and the placebo group with respect to plaque inhibition within this study design. 相似文献
128.
病理医生对胃癌癌前病变特别感兴趣,西方国家和日本已提出用不同名称来确定这种病变。因此重要的是取得国际共识,以便在不同研究机构之间,特别在日本和西方研究者之间进行比较。文中提出的这一分类是由不同国家的病理学专家专门提出的,下列序号为原分类编号。1 无异型增生1.0 正常 粘膜成分即胃小凹、腺颈部、腺体和间质完好地保持其位置和比例,炎细胞浸润轻微或缺乏。1.1 反应性胃小凹上皮增生 见于胃粘膜对有丝分裂刺激物反应时,可能是感染性的,也可能是化学性的,或是在糜烂、溃疡后的增生。胃小凹延长、弯曲;细胞核增大,有时染色质… 相似文献
129.
O Doody C Czarnecki MF Given Stuart M Lyon 《Journal of Medical Imaging and Radiation Oncology》2009,53(5):489-492
This study aimed to assess the role of percutaneous vertebroplasty (VP) in the management of acute traumatic burst fractures. We describe three cases where percutaneous VP was carried out for traumatic non‐osteoporotic burst vertebral fractures. For clinical symptoms and the effect of the VP procedure to be assessed, all patients completed a visual analogue scale and a mobility score before the procedure and at day 1 and 3 months post procedure. Improvements in both pain and mobility scores immediately post procedure were seen in all patients, and these results persisted at 3‐month follow up. Percutaneous VP provided a successful, minimally invasive treatment of these patients' traumatic fractures while avoiding major surgical procedures and associated surgical morbidity and complications. 相似文献
130.
Wiem Lassoued Danielle Murphy Jeff Tsai Ridha Oueslati Gavin Thurston William MF Lee 《Cancer biology & therapy》2010,10(12):1326-1333
Vascular endothelial growth factor (VEGF) A is a major promoter of tumor angiogenesis and a prime target of antiangiogenic cancer therapy. To examine whether endothelial cell signaling might provide histological biomarkers of angiogenesis and VEGF activity in vivo, normal mouse organs and multiple tumor models were studied immunohistochemically for endothelial expression of activated ERK, STAT3 and AKT. Phospho(p)-ERK and p-STAT3 expression was negligible in the endothelia of normal organs but was significantly elevated in tumor endothelium. p-AKT was present at significant and comparable levels in both tumor and normal endothelia. In K1735 tumors induced to express more VEGF, endothelial p-ERK, p-STAT3 and p-AKT increased accompanied by signs of accelerated angiogenesis. Treatment of K1735 and Colo-205 tumors with the VEGF inhibitor, VEGF Trap (aflibercept), decreased tumor endothelial p-ERK, p-STAT3 and p-AKT expression accompanied by signs of antiangiogenic effect. These results show that endothelial p-ERK and p-STAT3 (but not p-AKT) distinguish tumor from normal vessels and that the presence of these two signaling intermediates may be useful indicators of tumor angiogenic activity and angiogenesis inhibition by VEGF antagonists.Key words: VEGF, VEGF Trap, endothelial cells, signal transduction, angiogenesis, biomarker, p-ERK, p-STAT3, p-AKT 相似文献