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排序方式: 共有585条查询结果,搜索用时 15 毫秒
91.
Emanuel Gaziano MD Cecilie Gaziano PhD Debra Brandt RT RDMA 《American journal of obstetrics and gynecology》1998,178(6):1359-1367
OBJECTIVE: Our purpose was to study fetal growth and blood flow distribution in diamniotic monochorionic compared with dizygotic (diamniotic dichorionic) twins by use of Doppler velocimetry of the umbilical artery and middle cerebral artery. STUDY DESIGN: Study candidates were divided into group A, consisting of 33 pairs (66 fetuses) of diamniotic monochorionic twins, and group B, 50 pairs (100 fetuses) of diamniotic dichorionic twins. Diamniotic monochorionic placentation was confirmed by microscopic placental examination for group A. Diamniotic dichorionic placentation was ensured for group B by selecting only twins with different-sex pairs (dizygotic twins). Targeted ultrasonography with biometry was performed in each twin, and Doppler recordings of the umbilical artery and middle cerebral artery were obtained. Waveforms were analyzed and the systolic/diastolic ratio, the resistance index, and a measure of blood flow redistribution (brain-sparing effect), the cerebral/placental ratio, was calculated for each fetus. Growth status at birth was assessed by the number of small-for-gestational-age infants (≤10th percentile), low-birth-weight infants (≤25th percentile), and percent of growth discordance between twins. Intertwin differences were assessed by Δ values (value of larger twin minus value of smaller twin). RESULTS: Diamniotic monochorionic compared with dizygotic twins demonstrated a significantly greater probability of blood flow redistribution. For the study population as a whole, the brain-sparing effect was noted in 67% of small-for-gestational-age babies and only 7% of non-small-for-gestational-age infants (p ≤ 0.001). For the diamniotic monochorionic pregnancies blood flow redistribution occurred in 6 of 10 small-for-gestational-age infants (60%) and 6 of 46 non-small-for-gestational-age infants (13%). In the diamniotic monochorionic group small-for-gestational-age compared with non-small-for-gestational-age infants were more likely to show blood flow redistribution, which was the result of significantly decreased resistance in the middle cerebral artery and significantly increased resistance in the umbilical artery. Small-for-gestational-age infants (≤10th percentile) occurred much less frequently in the dizygotic group. Two of two small-for-gestational-age infants in the dizygotic group showed blood flow redistribution. Although the extremes of birth weight were more common in the diamniotic monochorionic group, both groups had relatively large numbers of small babies with birth weights in the lower 25th percentile (50.0% for diamniotic monochorionic and 44.0% for dizygotic twins, not significant). However, 42.3% (11/26) of diamniotic monochorionic twins who were in the low-birth-weight group showed blood flow redistribution compared with only 3.3% (1/30) whose birth weights were ≥25th percentile (p ≤ 0.001). In the dizygotic twins 10% of lower-birth-weight infants redistributed blood flow compared with 1% in the higher-birth-weight group, a nonsignificant difference. Diamniotic monochorionic compared with dizygotic twins were delivered earlier (32.9 weeks vs 34.8 weeks, p ≤ 0.001), were smaller (1832 gm vs 2304 gm, p ≤ 0.001), showed higher birth weight discordance (29.8% vs 14%, p ≤ 0.05), and had greater numbers (19.7% vs 2.3%, p ≤ 0.01) of infants at ≤10th percentile birth weight. CONCLUSIONS: Diamniotic monochorionic twins from the lower-birth-weight groups more often show blood flow redistribution compared with dizygotic twins of similar low birth weights. Placental vascular connections and the attendant hemodynamic changes in the fetuses of diamniotic monochorionic twins probably account for this difference. Brain-sparing events occur commonly without clinical twin transfusion syndrome in this group. These findings have implications for management. (Am J Obstet Gynecol 1998;178:1359-67.) 相似文献
92.
Xi Zheng Wang Yi Bo Wen Xiao Ping Shang Yi He Wang Yan Wei Li Tian Fang Li Shou Lin Li Jing Yang Yan Jin Liu Xiao Ping Lou Wei Zhou Xing Li Jian Jiang Zhang Cui Ping Song Cecilie Siggaard Jorgensen Soren Rittig Stuart Bauer Giovanni Mosiello Qing Wei Wang Jian Guo Wen 《Neurourology and urodynamics》2019,38(5):1423-1429
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94.
Gaullier JM Sleboda J Øfjord ES Ulvestad E Nurminiemi M Moe C Tor A Gudmundsen O 《International journal of medicinal mushrooms》2011,13(4):319-326
Lentinus edodes (Shiitake) is a medicinal mushroom with a long tradition of use in Asia. The major active substance in L. edodes is a (1-6,1-3)-beta-glucan (lentinan). No clinical controlled studies have yet investigated the effect of orally administered lentinan on the immune response in healthy, elderly Caucasian subjects. We evaluated the effect and the safety of a beta-glucan from L. edodes mycelium, Lentinex, in healthy, elderly subjects in a double blind, crossover, placebo-controlled trial. Forty-two subjects were randomly allocated to two groups given orally either 2.5 mg/day Lentinex or placebo for 6 weeks; then after a washout period of 4 weeks, the alternate supplementation was given for 6 weeks. The changes in the number of B-cells were significantly different between the groups. The number ofNK cells increased significantly in both groups, but there was no significant difference between the groups. Other factors of the immune response (immunoglobulins, complement proteins, cytokines) were not altered. The safety blood variables (differential cell count, liver function, kidney function, and other blood chemistry) were not influenced by Lentinex, and the number, nature, and severity of adverse events were similar to placebo. Lentinex given orally to elderly subjects was safe and induced an increase in the number of circulating B-cells. 相似文献
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97.
Blimark C Veskovski L Westin J Rödjer S Brune M Hjorth M Holmberg E Andersson PO Mellqvist UH 《European journal of haematology》2011,87(2):117-122
Introduction: Today, a number of therapeutic options are available as the patient with myeloma relapses from initial treatment with high‐dose melphalan and autologous stem cell transplantation (ASCT). For patients who experience a durable response to primary ASCT, retreatment with high‐dose melphalan is recommended by many current guidelines. Yet, toxicity is an important aspect in the choice of relapse treatment, and a second ASCT in this setting could be associated with enhanced toxicity. As the goal for the treatment for relapsed myeloma should be disease control while maintaining quality of life, lower doses of melphalan might be preferable. Methods and Objectives: In this retrospective study, we account for the outcome of 66 patients with myeloma in first systemic relapse after ASCT, who were treated with intermediate‐dose melphalan, 100 mg/m2, and stem cell support (MEL 100). The aim was to evaluate this treatment in relation to prior response duration after initial ASCT and with respect to response rate, toxicity and survival. Results: The overall response rate was 62%. There was limited, mostly haematological, toxicity, and no treatment–related mortality was observed. The median progression‐free survival (PFS) was 8.5 months, and the median overall survival was 24 months. Patients with time to progression of 34 months or more (n = 17; ≥75th percentile) after initial ASCT had a median PFS of 12.5 months after MEL 100. Conclusion: For patients with a long‐lasting response after ASCT, MEL 100 could be a therapeutic option with low toxicity and with efficacy comparable to newer immunomodulatory drugs. 相似文献
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100.
Inga‐Cecilie Sørheim Ane Johannessen Thomas Blix Grydeland Ernst Reidar Omenaas Amund Gulsvik Per Sigvald Bakke 《The clinical respiratory journal》2010,4(2):89-96
Introduction: Sampling is regarded as crucial to the validity of case–control studies. Ideally, cases and controls should be selected from the same source population, but deviations from this approach are often seen. Objective: Our objective was to examine how exposure–disease relationships in a study on chronic obstructive pulmonary disease (COPD) were affected by the sampling sources of cases and controls. Methods: A Norwegian case–control study on COPD including 1909 subjects used three sources of recruitment for cases (general population, hospital registry and volunteers) and two sources for controls (general population and volunteers). This resulted in six sampling combinations of cases and controls (groups A–F). We examined how the risk factors gender, age, smoking, educational level and comorbidity were associated with COPD in these six sampling groups. Results: Several exposure–disease associations were dependent on variation in sampling source, thereby demonstrating the possibility of selection bias. The theoretically most ideal sampling group is likely group A, where both cases and controls are recruited from a general population. When using group A as a reference, the groups containing either voluntary controls and/or hospital‐based cases deviated the most, suggesting higher susceptibility to selection bias in these groups. Conclusion: Recruitment from several sources made our study design vulnerable to selection bias. Our findings should bring about increased awareness to the sampling process, and encourage sampling of cases and controls from the same source population in future studies. Please cite this paper as: Sørheim I‐C, Johannessen A, Grydeland TB, Omenaas ER, Gulsvik A and Bakke PS. Case–control studies on risk factors for COPD: how does the sampling of the cases and controls affect the results? The Clinical Respiratory Journal 2010; 4: 89–96. 相似文献