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991.
Cornelis J.J. Boogerd Antoon F.M. Moorman Phil Barnett 《Anatomical record (Hoboken, N.J. : 2007)》2010,293(6):998-1001
Msx1 and Msx2 are essential for the development of many organs. In the heart, they act redundantly in development of the cardiac cushions. Additionally, Msx2 is expressed in the developing conduction system. However, the exact expression of Msx1 has not been established. We show that Msx1 is expressed in the cardiac cushions, but not in the myocardium. In Msx2‐null mice, Msx1 is not ectopically expressed in the myocardium. The absence of myocardial defects in the Msx2 knock‐out can therefore not be attributed to a redundant action of Msx1 in the myocardium. Anat Rec, 2010. © 2010 Wiley‐Liss, Inc. 相似文献
992.
OBJECTIVE: The claim that a planned repeat cesarean delivery is safer than a trial of labor after cesarean may not be applicable to women who desire larger families. The aim of this study was to assess maternal complications after multiple cesarean deliveries. METHODS: The records of women who underwent two or more planned cesarean deliveries between 2000 and 2005 were reviewed. We compared maternal complications occurring in 277 women after three or more cesarean deliveries (multiple-cesarean group) with those occurring in 491 women after second cesarean delivery (second-cesarean group). RESULTS: Excessive blood loss (7.9% versus 3.3%; P < .005), difficult delivery of the neonate (5.1% versus 0.2%; P < .001), and dense adhesions (46.1% versus 25.6%; P < .001) were significantly more common in the multiple-cesarean group. Placenta accreta (1.4%) and hysterectomy (1.1%) were more common, but not significantly so, in the multiple-cesarean group. The proportion of women having any major complication was higher in the multiple-cesarean group, 8.7% versus 4.3% (P = .013), and increased with the delivery index number: 4.3%, 7.5%, and 12.5% for second, third, and fourth or more cesarean delivery, respectively (P for trend = .004). CONCLUSION: Multiple cesarean deliveries are associated with more difficult surgery and increased blood loss compared with a second planned cesarean delivery. The risk of major complications increases with cesarean delivery number. LEVEL OF EVIDENCE: II-2. 相似文献
993.
For the step-and-shoot intensity-modulated radiation therapy (IMRT) technique, the combination of high dose rate, multiple beam segments and low dose per segment can lead to significant differences between the planned dose and the dose delivered to the patient. In this technique, a dose delivery inaccuracy known as the 'overshoot' effect is caused by the dose servo control system. This typically occurs in the first and last beam segments and causes an over- and underdose, respectively. Some dose positional error in the segment sequence is also possible there. Commercial ionization chambers (RK-type) and radiographic Kodak films were used for the measurements. The reported results were obtained using the Pinnacle(3)-V6.2 treatment planning system and a Varian Clinac 21 EX linear accelerator equipped with a 120-leaf Millennium MLC. The dose inaccuracy measurements were based on the comparison of the dose and profiles for reference fields and fields irradiated with the step-and-shoot technique. For our linear accelerators, an 'overshoot' effect ranging from 0.1 to 0.6 MU was found, corresponding to a dose rate from 100 to 600 MU min(-1), respectively. For segments with off-axis distances from 0 to 5.5 cm with >3.5 MU per segment and all dose rates, a MLC leaf-position error of <1 mm was measured. For segments with an off-axis distance of 9.5 cm, a positional error >2 mm was measured for 600 MU min(-1) and 1 MU per segment. The purpose of this study was to find a correction method for segmental dose errors caused by the 'overshoot' effect when small monitor unit and high dose rate are used. To better represent the fluctuation of the segment doses in the beam, a dose ratio between reference and step-and-shoot irradiated fields was defined. A method for the correction of segment dose inaccuracies and a quality assurance programme for the 'overshoot' effect were developed. The ordering of the biggest segment shape in the segment sequence was studied for ten randomly selected prostate patients planned for IMRT. The results of this work can be used to improve the agreement between the planned and delivered doses for IMRT. 相似文献
994.
995.
Chao ST Thakkar VV Barnett GH Vogelbaum MA Angelov L Weil RJ Rasmussen P Reuther AM Jamison B Neyman G Suh JH 《Technology in cancer research & treatment》2012,11(2):117-122
Purpose of this study is to determine the types, incidence, and severity of acute complications of intracranial stereotactic radiosurgery (SRS), specifically Gamma Knife (GK). Patients who had never had previous SRS were eligible for this prospective IRB-approved study. The questionnaire used applicable questions from CTCAE v.3.0, the Brief Pain Questionnaire (Short Form), Brief Fatigue Inventory, and the Tinnitus Handicap Inventory. Questionnaires were obtained prior to Gamma Knife (GK), 1 week, 1 month, and 2 months to assess complications. Seventy-six eligible patients (median age of 62 years) had complete data and were analyzed. Diagnoses included: 26 (34%) with brain metastases, 15 (20%) with trigeminal neuralgia, 12 (16%) with schwannoma, 10 (13%) with meningioma, 7 (9%) with arteriovenous malformation, 3 (4%) with pituitary adenoma, and 3 (4%) with other. At 1 week, 24% developed minimal scalp numbness (p =?0.0004 baseline compared to 1 week). Only 13% had minimal scalp numbness at 1 month and 2% at 2 months (both p?5?NS compared to baseline). There was no difference in scalp tingling between baseline and the various time points. Thirteen percent developed pin site pain at 1 week with a median intensity level of 2 out of 10. By one month, only 3% had pin site pain with a median intensity level of 3 out of 10. Four percent developed pin-site infection at 1 week and none at 1 and 2 months. There was no significant difference in nausea from baseline at 1 week, but there was worsening nausea at 1 month (p =?0.0114). By 1 month, 10% reported new local hair loss. 23%, 16%, and 15% complained of new/worsening fatigue at 1 week, 1 month, and 2 months, respectively, but 40% reported fatigue at baseline. Balance improved following SRS over all time periods (for all comparisons, p 0.009). 1%, 6%, and 3% developed new tinnitus at 1 week, 1 month, and 2 months, respectively, which was significant when comparing baseline to non-baseline (p =?0.0269). Thirty-two patients were employed prior to SRS. Three (9%) patients did not return to work. Twenty-seven (84%) patients returned to work a median of 4 days after SRS. Two people did not report their employment status after SRS. There was no significant difference in face swelling, headache, eye pain, vomiting, seizures, or passing out at any intervals compared to baseline. This prospective study demonstrates that GK is well tolerated with few patients developing major acute effects. Many patients are able to return to work shortly after GK. 相似文献
996.
Mahoney G Slade GD Kitchener S Barnett A 《Community dentistry and oral epidemiology》2008,36(6):485-492
Abstract – While there is good evidence of caries‐preventive benefits of fluoride in drinking water among children and adolescents, there is little information about effectiveness of water fluoridation among adults. Objectives: To determine whether exposure to fluoride in drinking water is associated with caries experience in Australian Defence Force (ADF) personnel. Methods: Cross‐sectional study of 876 deployable ADF personnel aged 17–56 years. At each person’s mandatory annual dental examination, military dentists recorded the number of decayed, missing and filled teeth (DMFT) using visual, tactile and radiographic criteria. Participants also completed a questionnaire, listing residential locations in each year from 1964 to 2003. People were classified into four categories according to the percentage of their lifetime living in places with fluoridated water: <10%, 10% to <50%, 50% to <90% and ≥90%. Mean DMFT was compared among those categories of fluoridation exposure and the association was evaluated statistically using analysis of variance to adjust for age, sex, years of service and rank. Results: Without adjustment for confounders, the mean DMFT (±95% confidence interval) was 6.3 ± 0.8 for <10% fluoridation exposure, 7.8 ± 0.8 for 10% to <50% exposure, 7.5 ± 0.7 for 50% to <90% exposure and 4.6 ± 0.6 for ≥90% exposure (P < 0.01). However, age was inversely associated with mean DMFT and in the <10% exposure group, 91% of people were aged <35 years. Service rank was also significantly associated with both fluoridation exposure and DMFT. After adjustment for all covariates, mean DMFT was 24% lower among people in the two groups with ≥50% exposure compared with the <10% exposure group. Conclusions: Degree of lifetime exposure to fluoridated drinking water was inversely associated with DMFT in a dose–response manner among this adult military population. 相似文献
997.
Gauvin L Riva M Barnett T Richard L Craig CL Spivock M Laforest S Laberge S Fournel MC Gagnon H Gagné S 《American journal of epidemiology》2008,167(8):944-953
This paper examines the association between neighborhood active living potential and walking among middle-aged and older adults. A sample of 2,614 (61.1% women) persons aged 45 years or older and living in one of 112 census tracts in Montreal, Canada, were recruited between February and May of 2005 to participate in a 20-minute telephone survey. Data were linked to observational data on neighborhood active living potential in the 112 census tracts and analyzed through multilevel modeling. Greater density of destinations in the census tract was associated with greater likelihoods of walking for any reason at least 5 days per week for at least 30 minutes (odds ratio = 1.53, 95% confidence interval: 1.21, 1.94). Associations were attenuated but remained statistically significant after controlling for socioeconomic, health, lifestyle, and other physical activity characteristics. Sensitivity analyses showed that associations were robust across smaller and larger volumes of walking. No associations were found between dimensions of neighborhood active living potential and walking for recreational reasons. The authors conclude that a larger number and variety of neighborhood destinations in one's residential environment are associated with more walking and possibly more utilitarian walking among middle-aged or older adults. 相似文献
998.
David M. Peereboom Dale R. Shepard Manmeet S. Ahluwalia Cathy J. Brewer Neeraj Agarwal Glen H. J. Stevens John H. Suh Steven A. Toms Michael A. Vogelbaum Robert J. Weil Paul Elson Gene H. Barnett 《Journal of neuro-oncology》2010,98(1):93-99
Approximately 40–50% of glioblastomas (GBM) overexpress epidermal growth factor receptor (EGFR). Erlotinib is a specific and potent EGFR tyrosine kinase inhibitor active against refractory GBM. Patients with non-small cell lung cancer and ≥grade 2 erlotinib-induced rash have improved survival. This phase 2 study assessed the efficacy and safety of concurrent radiation therapy (RT) and temozolomide with pharmacodynamic dose escalation of erlotinib in patients with newly diagnosed GBM. Patients received RT 60 Gy in 30 fractions with concurrent temozolomide 75 mg/m2/day × 42 days, followed in four weeks by temozolomide 150–200 mg/m2/day × 5, every 28 days for 12 cycles. Patients received erlotinib, 50 mg/day and increased by 50 mg/day every 2 weeks until the occurrence of grade 2 rash or to a maximum dose of 150 mg/day, from day 1 until disease progression. Twenty-seven patients were treated in this study. Twenty-two (81%) patients came off study for progressive disease (18 [67%]) or adverse events (4 [15%]). Eighteen patients (67%) have died. Median progression-free survival was 2.8 months, and the median overall survival was 8.6 months. Five patients remain on study with a median follow-up of 16 months. Grade 3/4 toxicities included thrombocytopenia, anemia, lymphopenia, fatigue, and febrile neutropenia. There were four deaths on study, three definitely treatment-related; therefore, the trial was terminated after accrual of 27 of 30 planned patients. Erlotinib co administered with RT and temozolomide was not efficacious and had an unacceptable toxicity. 相似文献
999.
Barnett PV Bashiruddin JB Hammond JM Geale DW Paton DJ 《Revue scientifique et technique (International Office of Epizootics)》2010,29(3):593-602
A network of foot and mouth (FMD) vaccine banks has been initiated with the support of vaccine bank managers and technical advisors that participated in a workshop held at the Institute for Animal Health, Pirbright, in the United Kingdom in April 2006. Terms of Reference that provide guidance for coordinated activities are under consultation. Practical and economic benefits can be realised from collaboration, which will be achieved through mutually acceptable mechanisms for the exchange of information and materials relevant to vaccine banks and their management. If administrative and technical hurdles can be overcome, the network has the potential to contribute significantly to the improved control of FMD worldwide. A 'global' and interactive vaccine bank association could be created by agreeing a system of resource sharing that could orchestrate additional emergency cover with vaccine or antigen from the reserves of network members. 相似文献
1000.
Yuming Guo Shilu Tong Shanshan Li Adrian G Barnett Weiwei Yu Yanshen Zhang Xiaochuan Pan 《Environmental health : a global access science source》2010,9(1):57