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排序方式: 共有980条查询结果,搜索用时 203 毫秒
31.
32.
Fiona L. Britten Ching T. Lai Donna T. Geddes Leonie K. Callaway Emma L. Duncan 《Nutrients》2022,14(7)
(1) Background: Breastfeeding duration may be reduced in women with type 2 diabetes. Delayed secretory activation (SA) is associated with poorer breastfeeding outcomes; however, no prior studies have examined SA in women with type 2 diabetes. This pilot study aimed to assess SA in women with type 2 diabetes by assessing breastmilk constituents. Secondary aims were to assess breastfeeding rates postpartum, and contributory factors. (2) Methods: A prospective cohort of pregnant women with type 2 diabetes (n = 18) and two control groups with age- and parity-matched nondiabetic pregnant women (body mass index (BMI)) matched (n = 18) or normal-range BMI (n = 18)) were recruited. Breastmilk constituents (citrate, lactose, protein, and fat) were measured twice daily for 5 days postpartum and compared between groups. Associations between peripartum variables, breastmilk constituents, and breastfeeding at 4 months postpartum were explored. (3) Results: Women with type 2 diabetes had a slower increase in breastmilk citrate concentration postpartum, indicative of delayed SA, compared to both control groups. Higher predelivery insulin doses in women with type 2 diabetes were associated with increasing time to SA. Both women with type 2 diabetes and BMI-matched controls were less likely to fully breastfeed at 4 months, compared with normal-BMI controls. (4) Conclusion: SA is delayed in women with type 2 diabetes when compared to BMI-matched and normal-BMI women. Women with type 2 diabetes are less likely to fully breastfeed, at hospital discharge and by 4 months postpartum, compared to women with normal-BMI. 相似文献
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Percutaneous radiofrequency ablation of hepatocellular carcinoma as a bridge to liver transplantation 总被引:28,自引:0,他引:28
Lu DS Yu NC Raman SS Lassman C Tong MJ Britten C Durazo F Saab S Han S Finn R Hiatt JR Busuttil RW 《Hepatology (Baltimore, Md.)》2005,41(5):1130-1137
Orthotopic liver transplantation (OLT) can be a definitive treatment for patients with hepatocellular carcinoma (HCC). Prolonged waiting times for cadaveric livers, however, may lead to dropout from the waiting list or worsened post-OLT prognosis as a result of interval tumor progression. Percutaneous radiofrequency ablation (RFA) is widely used for local control of small unresectable HCC, but its pretransplant role remains unclear. We studied the outcome of 52 consecutive patients accepted for OLT bearing 87 HCC nodules and treated with percutaneous RFA. On initial staging, the tumor burden exceeded the Milan criteria in 10 patients. Complete tumor coagulation was observed in 74 of 87 (85.1%) nodules based on postablation imaging. After a mean of 12.7 months (range: 0.3-43.5) on the waiting list, 3 of 52 patients (5.8%) had dropped out due to tumor progression. Forty-one patients had undergone transplantation, with 1- and 3-year post-OLT survival rates of 85% and 76%, respectively. No patient developed HCC recurrence. There were three major complications in 76 RFA procedures (hepatic arterial hemorrhage, small bowel perforation, and liver decompensation salvaged by OLT), without resultant death or dropout. In conclusion, percutaneous RFA is an effective bridge to OLT for patients with compensated liver function and safely accessible tumors. Tumor-related dropout rate and post-OLT outcome compared favorably with published controls of patients with early-stage disease. This can be attributed to the efficacy of RFA in producing local cure or curbing tumor progression during the waiting period. 相似文献
35.
Recent studies of the intrinsic cellular sensitivity of 30 human in vitro cell lines to 4 MeV photons and 62.5 MeV (p⇒ Be+) neutrons have identified relatively neutron sensitive cell lines with high alpha values within the more resistant end of the photon radiation response range. Here we present data comparing the surviving fraction at 2 Gy of photons (SF2) to the surviving fractions at 1.6, 0.85 and 0.6 Gy of neutrons respectively (SF 1.6 SF0.8S and SF0.6). With the ratio SF2/SF1.6 a negative trend can be seen between the probability of a preferential response to neutrons and relative photon resistance. With a ratio of SF2/SF0.6, however, a highly significant benefit for 62.5 MeV neutrons can be seen in the more photon resistant lines. We suggest further clinical studies to explore the potential relevance of these in vitro findings to the clinical situation should be undertaken. 相似文献
36.
David RH Christie Kenneth W Tiver 《Journal of Medical Imaging and Radiation Oncology》1996,40(3):331-333
Five patients who received radiotherapy (RT) for 7 melanotic freckles (MF, also known as Hutchinson's freckles, lentigo maligna) were reviewed 8 to 37 months after their treatment by RT. Local control and a favourable cosmetic result occurred in all patients. Treatment toxicity was minimal. Few reports about the use of RT for MF exist. Many other treatments including observation alone have been associated with high rates of recurrence, and in some cases conversion to invasive melanoma has occurred. RT appears to be a safe and effective treatment for this condition, providing that doses equivalent to 44 Gy in 11 fractions or more are given. 相似文献
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Heart-rate-adapted image reconstruction in multidetector-row cardiac CT: influence of physiological and technical prerequisite on image quality 总被引:9,自引:8,他引:1
Herzog C Abolmaali N Balzer JO Baunach S Ackermann H Dogan S Britten MB Vogl TJ 《European radiology》2002,12(11):2670-2678
The purpose of this study was to develop strategies for optimal image reconstruction in multidetector-row cardiac CT and
to discuss the results in the context of individual heart rate, cardiac physiology, and technical prerequisite. Sixty-four
patients underwent multidetector-row cardiac CT. Depending on the heart rate either a single-segmental reconstruction (SSR)
or an adaptive two-segmental reconstruction (ASR) was applied. Image reconstruction was done either antegrade (a) or retrograde
(r) in relation to the R-peak. Reconstruction of all data sets was performed at multiple time points within the t-wave/p-wave
interval, differing from each other by 50 ms. In addition, each reconstruction was assigned to one of six reconstruction intervals
(A–F), each corresponding to a specific event in the cardiac cycle. While no significant time points were found for absolute
values, the following interval/reconstruction technique combinations provided significant better image quality: F/r at HR
<60 bpm for all coronary segments (p≤0.004) and at HR 60–65 bpm for segments 5–10 (p≤0.001); B/a at HR 60–65 bpm for segments 1–4 and 11–15 (p<0.001) and at HR >65 bpm for all segments (p≤0.002). The results show that in order to achieve optimal image quality, image reconstruction has to be adjusted to each
patient's ECG curve and heart rate individually. The moment of reconstruction should be determined as absolute rather than
as relative distance from the previous R-peak.
Electronic Publication 相似文献
39.
The macaque medial superior temporal area (MST) is proposed to be specialized for analyzing complex 'optic flow' information. Such space-varying motion patterns provide a rich source of information about self motion, scene structure and object shape. We report the performance of rhesus macaques on a two-alternative 'heading' task, in which they reported whether horizontally varying, simulated trajectories were to left or right of center. Monkeys were sensitive to small heading angles; thresholds averaged 1.5-3 degrees. Heading estimates were stable in the face of changing stimulus location and smooth pursuit eye movements. In addition, we tested the role of area MST in heading judgements by electrically activating columns of neurons in this area while the monkeys performed the heading task. Activation of MST frequently affected performance, usually causing choice biases. These induced biases were often large and usually concordant with the preference of the neurons being activated. In addition, the induced biases were often larger in the presence of smooth pursuit eye movements. These results favor the hypothesis that MST is involved in recovering self-motion direction from optic flow cues and in the process by which heading perception is compensated for ongoing eye movements. 相似文献
40.