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81.
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83.
S F Wong A Lee-Tannock D Amaraddio F Y Chan H D McIntyre 《Ultrasound in obstetrics & gynecology》2006,28(7):934-938
OBJECTIVE: To assess the effect of glucose control on the rate of growth of fetuses in women with pregestational diabetes mellitus (Types 1 and 2). METHODS: All pregestational diabetic women booked at Mater Mothers' Hospital, Brisbane, Australia, between 1 January 1994 and 31 December 2002, were included. Pregnancies with congenital fetal anomalies, multiple pregnancies, and pregnancies terminated prior to 20 weeks' gestation were excluded. Dating scans were performed before 14 weeks' gestation and serial scans were performed at 18, 24, 28, 32 and 36 weeks. Fetal parameters, including biparietal diameter, femur length and abdominal circumference, were recorded. The daily growth rates for biparietal diameter, femur length, and fetal abdominal area were calculated and compared with those in a low-risk (non-diabetic) population. The growth rates in fetuses of women with satisfactory diabetic control (HbA1c < 6.5%) and unsatisfactory control (HbA1c > or = 6.5%) in the three trimesters were compared. RESULTS: A total of 174 diabetic pregnancies were included and a total of 997 ultrasound scans were performed. The growth rates for fetuses of mothers with diabetes mellitus were significantly higher than for those in the low-risk population. The z-scores for biparietal diameter, femur length, and fetal abdominal area were 0.18, 0.59 and 1.44, respectively. Fetuses of diabetic mothers with high HbA1c in the first trimester had significantly greater fetal abdominal area growth rate than those with normal HbA1c (fetal abdominal area z-score of 1.7 vs. 0.75, P = 0.009). Although the fetal abdominal area z-scores in fetuses of diabetic mothers with high HbA1c in the second or third trimesters were also higher than those with normal HbA1c levels, the differences did not reach statistical significance. Maternal obesity did not influence the fetal growth rate. CONCLUSION: The rate of growth of fetuses of diabetic mothers differs from that of the normal population. Growth acceleration persists until the late third trimester. Moreover, periconceptional glucose control appears to have a significant effect on accelerated growth of the fetal abdominal area. 相似文献
84.
A. Nakao H. Toyokawa A. Tsung M. A. Nalesnik D. B. Stolz J. Kohmoto A. Ikeda K. Tomiyama T. Harada T. Takahashi R. Yang M. P. Fink K. Morita A. M. K. Choi N. Murase 《American journal of transplantation》2006,6(10):2243-2255
Carbon monoxide (CO), a byproduct of heme catalysis, was shown to have potent cytoprotective and anti-inflammatory effects. In vivo recipient CO inhalation at low concentrations prevented ischemia/reperfusion (I/R) injury associated with small intestinal transplantation (SITx). This study examined whether ex vivo delivery of CO in University of Wisconsin (UW) solution could ameliorate intestinal I/R injury. Orthotopic syngenic SITx was performed in Lewis rats after 6 h cold preservation in control UW or UW that was bubbled with CO gas (0.1-5%) (CO-UW). Recipient survival with intestinal grafts preserved in 5%, but not 0.1%, CO-UW improved to 86.7% (13/15) from 53% (9/17) with control UW. At 3 h after SITx, grafts stored in 5% CO-UW showed improved intestinal barrier function, less mucosal denudation and reduced inflammatory mediator upregulation compared to those in control UW. Preservation in CO-UW associated with reduced vascular resistance (end preservation), increased graft cyclic guanosine monophosphate levels (1 h), and improved graft blood flow (1 h). Protective effects of CO-UW were reversed by ODQ, an inhibitor of soluble guanylyl cyclase. In vitro culture experiment also showed better preservation of vascular endothelial cells with CO-UW. The study suggests that ex vivo CO delivery into UW solution would be a simple and innovative therapeutic strategy to prevent transplant-induced I/R injury. 相似文献
85.
The onset of the sporadic Creutzfeldt-Jakob disease is usually characterized by dementia or neurological symptoms. We are reporting the case of a 31 year-old man with a sporadic Creutzfeldt-Jakob disease characterized by a schizophrenia-like onset. The schizophrenic symptoms developed for sixteen months before the neurological symptoms appeared. The psychiatric onset of the present case was linked with the early age of onset and the long duration of the disease and could have been influenced by polymorphism of the codon 129 of the prion protein gene (PRNP) and a type of pathological prion protein (PrPres). 相似文献
86.
Victor Aboyans Louis Labrousse Philippe Lacroix Jér?me Guilloux Seifeddine Sekkal Alexandre Le Guyader Elisabeth Cornu Marc Laskar 《European journal of cardio-thoracic surgery》2006,30(2):300-304
BACKGROUND: Despite major improvement in surgical techniques and intensive care management, stroke remains one of the most devastating complications of coronary artery bypass grafting (CABG). We aimed to determine factors predicting the occurrence of stroke during CABG. A special interest was focused on preoperative therapies. METHODS: We prospectively enrolled 810 consecutive candidates for CABG alone in a specific database, including all pre- and perioperative data (history, clinical, therapeutic, cardiac catheterization, surgical and intensive care data). Univariate tests and then multiple logistic regression analysis were used to determine independent predictive factors. RESULTS: During the first postoperative month, stroke occurred in 11 cases and transient ischemic attack (TIA) in 4 additive cases (cumulative rate: 1.85%). After the multivariate analysis, the following factors remained significant (p<0.05) in the predictive model, with corresponding odds ratios between brackets: redo cardiac surgery (7.45), unstable cardiac status (4.74), past history of cerebrovascular disease (4.14), past history of peripheral arterial disease (3.55), whereas the presence of preoperative statins was protective (0.24, 95% IC: 0.07-0.78). The addition of perioperative data (aortic calcification, postoperative arrhythmia, on/off-pump surgery) did not change the final predictive model. CONCLUSION: To our knowledge, this is the first real-world observational report highlighting the interest of statins for the prevention of stroke in the very special situation of CABG. Even though according to randomized trials coronary patients have a benefit from these drugs, a special level of interest should be directed towards those presenting the above-mentioned risk factors. 相似文献
87.
A Trakic F Liu H Sanchez Lopez H Wang S Crozier 《Magnetic resonance in medicine》2007,57(6):1119-1130
The switching of magnetic field gradient coils in magnetic resonance imaging (MRI) inevitably induces transient eddy currents in conducting system components, such as the cryostat vessel. These secondary currents degrade the spatial and temporal performance of the gradient coils, and compensation methods are commonly employed to correct for these distortions. This theoretical study shows that by incorporating the eddy currents into the coil optimization process, it is possible to modify a gradient coil design so that the fields created by the coil and the eddy currents combine together to generate a spatially homogeneous gradient that follows the input pulse. Shielded and unshielded longitudinal gradient coils are used to exemplify this novel approach. To assist in the evaluation of transient eddy currents induced within a realistic cryostat vessel, a low-frequency finite-difference time-domain (FDTD) method using the total-field scattered-field (TFSF) scheme was performed. The simulations demonstrate the effectiveness of the proposed method for optimizing longitudinal gradient fields while taking into account the spatial and temporal behavior of the eddy currents. 相似文献
88.
89.
O Schouten J H H van Laanen E Boersma R Vidakovic H H H Feringa M Dunkelgrün J J Bax J Koning H van Urk D Poldermans 《European journal of vascular and endovascular surgery》2006,32(1):21-26
OBJECTIVE: To evaluate the effect of statins on aneurysm growth in a group of consecutive patients under surveillance for infrarenal aortic aneurysms (AAA). MATERIALS AND METHODS: All patients (59 statin users, 91 non-users) under surveillance between January 2002 and August 2005 with a follow-up for aneurysm growth of at least 12 months and a minimum of three diameter evaluations were retrospectively included in the analysis. Multiple regression analysis, weighted with the number of observations, was performed to test the influence of statins on AAA growth rate. RESULTS: During a median period of 3.1 (1.1-13.1) years the overall mean aneurysm growth rate was 2.95+/-2.8 mm/year. Statin users had a 1.16 mm/year lower AAA growth rate compared to non-users (95% CI 0.33-1.99 mm/year). Increased age was associated with a slower growth (-0.09 mm/year per year, p = 0.003). Female gender (+1.82 mm/year, p = 0.008) and aneurysm diameter (+0.06 mm/year per mm, p = 0.049) were associated with increased AAA growth. The use of non-steroidal anti-inflammatory drugs, chronic lung disease, or other cardiovascular risk factors were not independently associated with AAA growth. CONCLUSIONS: Statins appear to be associated with attenuation of AAA growth, irrespective of other known factors influencing aneurysm growth. 相似文献
90.
Paul C. Willems Leon Elmans Patricia G. Anderson Wilco C. H. Jacobs Dick B. van der Schaaf Marinus de Kleuver 《European spine journal》2006,15(10):1487-1494
The results of lumbar fusion in chronic low back pain (LBP) patients vary considerably, and there is a need for proper patient selection. Lumbosacral orthoses have been widely used to predict outcome, however, with little scientific support. The aim of the present study was to determine the value of a pantaloon cast test in selecting chronic LBP patients for lumbar fusion or conservative management. First, a systematic review of the literature was carried out in which two independent reviewers identified studies in Medline, Cochrane and Current Contents databases. Three papers met the selection criteria. In the only study with a control group, a significantly better outcome after fusion compared to conservative treatment was found in patients who reported significant pain relief while in a cast (i.e. a positive cast test). The results of lumbar fusion, however, were not significantly different for patients with a positive and those with a negative cast test. In addition to the review, a clinical cohort study of 257 LBP patients, who had been allocated to either lumbar fusion or conservative management by a temporary external transpedicular fixation trial, was performed. Prior to allocation, all had undergone a pantaloon cast test. Patients with no history of prior spine surgery and with a positive pantaloon cast test had a better outcome after lumbar fusion than those treated conservatively (P = 0.002, χ
2 test). In patients with previous spine operations the outcomes were poor and the test was of no value. From the literature and the present patient cohort, it was concluded that only in chronic LBP patients without prior spine surgery, a pantaloon cast test with substantial pain relief suggests a favorable outcome of lumbar fusion compared to conservative management. The test has no value in patients who have had previous spine surgery. 相似文献