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131.
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
132.
Hercus TR; Cambareri B; Dottore M; Woodcock J; Bagley CJ; Vadas MA; Shannon MF; Lopez AF 《Blood》1994,83(12):3500-3508
Residues within the first and fourth helices of human granulocyte- macrophage colony-stimulating factor (hGM-CSF) were analyzed for their role in biologic activity and interaction with the alpha- and beta- chains of the hGM-CSF receptor. Within the first helix substitution of the surface residues Glu14, Asn17, Gln20, Arg23, Arg24, and Asn27 or the buried residues Ala18, Leu25, and Leu28 did not significantly impair bioactivity or receptor binding. Substitutions at the buried residues Ala22 and Leu26 had intermediate bioactivity. However, substitutions of the surface residue Glu21 or the buried residue Ile19 reduced the relative bioactivity of the analogues to as little as 0.45% and 0.3%, respectively. Substitution of the charged surface residues of the fourth helix showed that substitution at Glu104, Lys107, and Lys111 had no significant effect on bioactivity, but substitution at Glu108 and Asp112 reduced the potency of the analogues to 34% and 7%, respectively. Receptor binding studies showed that, whereas Glu21 is the critical residue for binding to the hGM-CSF-receptor beta-chain, Asp112 is likely to be involved in binding to the GM-CSF-receptor alpha- chain. These results establish the relative contribution of residues in the first and fourth helices for GM-CSF bioactivity and receptor binding, and support a model where the fourth helix of GM-CSF interacts with the alpha-chain, and the first helix with the beta-chain of the GM- CSF receptor. 相似文献
133.
134.
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
135.
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
136.
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
137.
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
138.
Marie Fanelli Kuczmarski R. T. Pohlig E. Stave Shupe A. B. Zonderman M. K. Evans 《The journal of nutrition, health & aging》2018,22(6):700-709
Objective
To determine the association of handgrip strength (HS) with protein intake, diet quality, and nutritional and cardiovascular biomarkers in African American and White adults.Design
Cross-sectional wave 3 (2009–2013) of the cohort Healthy Aging in Neighborhoods of Diversity across the Life Span (HANDLS) study.Participants
Socioeconomically diverse urban population of 2,468 persons aged 33 to 71 years.Measurements
Socio-demographic correlates, dietary intakes and biomarkers, HS, physical performance measures were collected. HS was measured using a dynamometer with the dominant hand. Functional measures included chair, tandem, and single leg stands. Two 24-hour recalls were collected using the US Department of Agriculture Automated Multiple Pass Method. The total protein intake and diet quality, evaluated by adherence to the DASH eating plan and Healthy Eating Index-2010, were calculated. Biomarkers included nutritional anemia, and serum levels of albumin, cholesterol, magnesium, and glucose.Results
The mean ±SE age of the sample was 52.3±0.2 years. Approximately 61% were African American and 57% were women. The mean ±SE HS of women was 29.1±0.2kg and for men was 45.9±0.4 kg. Protein, gm, per kg body weight for the women was 0.94±0.02 compared to 1.16 ±0.02 for men. After adjusting for socio-demographic factors, hypertension, and diabetes, HS/BMI ratio was significantly associated with protein intake per kg body weight (p<0.001) and diet quality, assessed by either the DASH adherence (p=0.009) or Health Eating Index-2010 (p=0.031) scores. For both men and women, participants in the upper tertile of HS maintained a single leg and tandem stances longer and completed 5 and 10 chair stands in shorter time compared to individuals in the lower HS tertile. Of the nutritional status indicators, the percent of men in the upper HS tertile with low serum magnesium and albumin, was significantly lower than those in the lower HS tertile [magnesium,7.4% vs 16.1%; albumin, 0.4% vs 4.5%]. The only difference observed for women was a lower percent of diabetes (14.4% for the upper HS tertile compared to 20.5% for the lower HS tertile.Conclusions
The findings confirm the role of protein and a healthful diet in the maintenance of muscle strength. In this community sample, HS was significantly associated with other physical performance measures but did not appear to be strongly associated with indicators of nutritional risk. These findings support the use of HS as a proxy for functional status and indicate the need for research to explore its role as a predictor of nutritional risk.139.
Marie Fanelli Kuczmarski Marc A. Mason Deanne Allegro Alan B. Zonderman Michele K. Evans 《Journal of the Academy of Nutrition and Dietetics》2013,113(12):1620-1631
BackgroundC-reactive protein (CRP), an inflammatory biomarker, is influenced by many factors, including socioeconomic position, genetics, and diet. The inverse association between diet and CRP is biologically feasible because micronutrients with antioxidative properties may enable the body to manage the balance between production and accumulation of reactive species that cause oxidative stress.ObjectiveTo determine the quality of the diet consumed by urban, low-income African-American and white adults aged 30 to 64 years, and association of diet quality with CRP.DesignData from a cross-sectional study were used to evaluate diet quality assessed by mean adequacy ratio (MAR). Two 24-hour recalls were collected by trained interviewers using the US Department of Agriculture automated multiple pass method.ParticipantsThe sample consisted of Healthy Aging in Neighborhoods of Diversity across the Life Span baseline study participants, 2004-2009, who completed both recalls (n=2,017).Main outcome measuresMAR equaled the average of the ratio of intakes to Recommended Dietary Allowance for 15 vitamins and minerals. CRP levels were assessed by the nephelometric method utilizing latex particles coated with CRP monoclonal antibodies.Statistical analysisLinear ordinary least square regression and generalized linear models were performed to determine the association of MAR (independent variable) with CRP (dependent variable) while adjusting for potential confounders.ResultsMAR scores ranged from 74.3 to 82.2. Intakes of magnesium and vitamins A, C, and E were the most inadequate compared with Estimated Average Requirements. CRP levels were significantly associated with MAR, dual-energy x-ray absorptiometry-measured body fat, and hypertension. A 10% increase in MAR was associated with a 4% decrease in CRP.ConclusionsThe MAR was independently and significantly inversely associated with CRP, suggesting diet is associated with the regulation of inflammation. Interventions to assist people make better food choices may not only improve diet quality but also their health, thereby possibly reducing risk for cardiovascular disease. 相似文献
140.
Selection of platelets for refractory patients by HLA matching and prospective crossmatching 总被引:2,自引:0,他引:2
G Moroff ; G Garratty ; JM Heal ; BR MacPherson ; D Stroncek ; ST Huang ; W Ho ; LD Petz ; MF Leach ; SS Lennon ; et al. 《Transfusion》1992,32(7):633-640
A multi-site clinical study compared platelets chosen for refractory patients by prospective platelet crossmatching using stored donor platelets and HLA-based selection. Seventy-three patients who were refractory to random-donor platelets received two plateletpheresis components, one chosen by HLA-based criteria and the other by crossmatching. Patients were carefully evaluated to exclude nonimmune factors that could adversely affect transfusion results. Each of the five study sites used a crossmatch procedure with which it had experience. Results from this study indicate the following: 1) The overall rate of successful transfusion was similar when an HLA-based method of donor selection that includes all grades of matching and mismatching was compared to a crossmatch-based method of donor selection. 2) HLA-based selection that restricts recipients to grade A and BU matches was superior to a selection method based upon crossmatching alone. Donor selection based on HLA matching (grades A or BU) was also superior to selection based on any degree of HLA mismatching (grades BX, C, or D). 3) Selection of donors based on HLA-cross-reactive groups (defined by in vitro serologic crossreactivity) was no more successful than that based on grade C and D mismatches and was no more successful than selection by crossmatching alone. 4) Lymphocytotoxic and platelet antibodies were not detected in many of the enrolled patients, even though patients demonstrating nonimmune factors were eliminated from the study. It can be concluded that HLA-compatible (grades A and BU) platelets provide optimal support for refractory patients, but that crossmatch-selected platelets are acceptable as an alternative component. 相似文献