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Birth weight on 12,644 singleton infants from 6,196 sibships born in Maryland between 1980 and 1984 were used to estimate the effects of nine maternal and infant covariates on the sibship correlation in birth weight. Assuming a homogeneous correlation across all families, the estimated intraclass correlation was 0.4664 (+/- 0.0099). This high sibship correlation makes it possible to predict, with reasonable accuracy, the birth weight of a child given information on previous sibs, as well as covariates on the mother and/or infant pertinent to a given pregnancy. The reduction in variance associated with incorporating information on the nine covariates used here was approximately equal to that obtained by conditioning on a single previous sib. Testing for heterogeneity in correlation among different groups of families showed that a crude measure of parity (first live birth vs. other), time between births, mother's marital status, and maternal age at the birth of the last child significantly influenced the sibship correlation in birth weight. 相似文献
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ME BURGE AM JOSHUA CM McNEIL R HUI MJ BOYER R ABRAHAM 《Asia-Pacific Journal of Clinical Oncology》2005,1(1):47-52
Background: Pemetrexed and cisplatin have recently been shown to significantly improve survival compared with cisplatin alone. However, there are only limited data reflecting teaching hospital experience outside a clinical trial. Pemetrexed has only been available in Australia on a restricted basis since 2002. We reviewed our experience of patients treated on the Australian ‘Special Access Scheme’ at three major thoracic oncology units. Methods: Charts were reviewed for all patients enrolled on the scheme. Data was extracted on age, World Health Organization (WHO) performance status, histology, prior therapy, time from diagnosis to starting pemetrexed, chemotherapy (pemetrexed alone or with a platinum), cycle number, response rate, actuarial progression‐free and overall survival. Doses were cisplatin 75 mg/m2 or carboplatin AUC = 5 and pemetrexed 500 mg/m2 every 21 days. Results: 52 patients (32 male and 20 female) were reviewed. Median age was 58 years and 88% were WHO 0–1. Histology included 54% epithelial, 17% biphasic (epithelial and sarcomatoid) and 21% undefined. The median time from diagnosis to administration of pemetrexed was 145 days. Sixty‐five percent had minimal surgical intervention with video assisted thoracoscopy, pleurodesis and biopsy, while 19% had received prior palliative radiation. Seventy‐one percent were chemotherapy naïve, the remaining 29% having received previous platinum and/or gemcitabine regimens. Twenty‐three percent had pemetrexed alone, 35% in combination with carboplatin and 42% with cisplatin. The median number of cycles was 4 (range 1–13). The response rate was 33%. No toxicity was observed in 20% grade 3–4 toxicity in 10% (majority nausea/vomiting). The median progression‐free and overall survival times from starting pemetrexed were 184 days and 298 days, respectively. Conclusions: Pemetrexed‐based regimens are safe and effective in a community setting in malignant mesothelioma. 相似文献
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CM Reid M. Nelson P. Beckinsale P. Ryan LMH Wing LJ Beilin MA Brown GLR Jennings CI Johnston J. Marley JJ McNeil TO Morgan J. Shaw ID Steven MJ West 《Clinical and experimental pharmacology & physiology》1997,24(5):370-373
1. The present study aimed to determine the feasibility of conducting a 5 year cardiovascular outcome trial of the treatment of 6000 elderly hypertensive patients in Australian general practices. 2. General practitioners (GPs) were invited to participate by mail and personal follow-up. Patient records were reviewed to identify subjects for a blood pressure (BP) screening programme. Blood pressure was measured on three occasions and eligible subjects were included if the average BP was 160 mmHg systolic or 90 mmHg diastolic if systolic BP was 140 mmHg. 3. Seven hundred and forty-one GPs were approached and 89 were enrolled in the study (12% of mail invites and 75% of those receiving a personal contact). In 16 practices where screening was completed, 82 000 records were reviewed to identify 4% patients eligible for screening. Twenty-two per cent of eligible subjects attended screening. Of 1938 subjects screened, 180 (9%) had BP 5=160/90 mmHg. Forty-seven percent of subjects (n = 916) were receiving antihypertensive therapy and 184 (20%) were withdrawn from therapy. One hundred and sixteen (63%) of these subjects had BP return to study entry levels within 6 weeks. Fifty-seven newly diagnosed and 81 previously treated subjects were randomized (7% of the screened population). 4. Based on the high participation rate of GPs, the response rate of patients to attend a BP screening programme and the 7% randomization to screening ratio for entry into the study, the ANBP2 pilot study has demonstrated that it is feasible to recruit subjects from Australian general practices to a cardiovascular outcome trial. 相似文献
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Siu Fai Li MD Nashat Latib MD Angela Kwong MD Shreni Zinzuwadia MD Ethan Cowan MD 《Academic emergency medicine》2007,14(12):1194-1196
Background In recent years, the number of women entering the field of emergency medicine (EM) has increased.
Objectives To determine if authorship in EM publications has increased in parallel with this trend.
Methods The gender of first and last authors of EM articles in Academic Emergency Medicine , American Journal of Emergency Medicine , Annals of Emergency Medicine , and Journal of Emergency Medicine were examined. The authors reviewed articles from 1985, 1995, and 2005 for American Journal of Emergency Medicine , Annals of Emergency Medicine , and Journal of Emergency Medicine and from 1999 and 2005 for Academic Emergency Medicine . The primary outcomes were the proportions of female authors.
Results A total of 2,016 articles were reviewed. Overall, 18% of first and last authors were female. Respectively, for 1985, 1995, 1999, and 2005, the proportions of female first authors were 9%, 15%, 19%, and 24%; the proportions of female last authors were 9%, 18%, 19%, and 22%. The trend of increases in female authorship was statistically significant.
Conclusions Although female authorship remains a minority in EM publications, it has increased significantly in parallel with increases in female participation in EM. 相似文献
Objectives To determine if authorship in EM publications has increased in parallel with this trend.
Methods The gender of first and last authors of EM articles in Academic Emergency Medicine , American Journal of Emergency Medicine , Annals of Emergency Medicine , and Journal of Emergency Medicine were examined. The authors reviewed articles from 1985, 1995, and 2005 for American Journal of Emergency Medicine , Annals of Emergency Medicine , and Journal of Emergency Medicine and from 1999 and 2005 for Academic Emergency Medicine . The primary outcomes were the proportions of female authors.
Results A total of 2,016 articles were reviewed. Overall, 18% of first and last authors were female. Respectively, for 1985, 1995, 1999, and 2005, the proportions of female first authors were 9%, 15%, 19%, and 24%; the proportions of female last authors were 9%, 18%, 19%, and 22%. The trend of increases in female authorship was statistically significant.
Conclusions Although female authorship remains a minority in EM publications, it has increased significantly in parallel with increases in female participation in EM. 相似文献
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Synergistic effects of Nell-1 and BMP-2 on the osteogenic differentiation of myoblasts. 总被引:1,自引:0,他引:1
Catherine M Cowan Xinquan Jiang Tiffany Hsu Chia Soo Beiji Zhang Joyce Z Wang Shun'ichi Kuroda Benjamin Wu Zhiyuan Zhang Xinli Zhang Kang Ting 《Journal of bone and mineral research》2007,22(6):918-930
Osteogenesis is synergistically enhanced by the combined effect of complimentary factors. This study showed that Nell-1 and BMP-2 synergistically enhanced osteogenic differentiation of myoblasts and phosphorylated the JNK MAPK pathway. The findings are important because of the osteochondral specificity of Nell-1 signaling and the potential therapeutic effects of coordinated BMP-2 and Nell-1 delivery. INTRODUCTION: BMPs play an important role in the migration and proliferation of mesenchymal cells and have a unique ability to alter the differentiation of mesenchymal cells toward chondrogenic and osteogenic lineages. Signaling upstream of Cbfa1/Runx2, BMPs effects are not limited to cells of the osteoblast lineage. Thus, additional osteoblast-specific factors that could synergize with BMP-2 would be advantageous for bone regeneration procedures. NELL-1 (NEL-like molecule-1; NEL [a protein strongly expressed in neural tissue encoding epidermal growth factor like domain]) is a novel growth factor believed to preferentially target cells committed to the osteochondral lineage. MATERIALS AND METHODS: C2C12 myoblasts were transduced with AdLacZ, AdNell-1, AdBMP-2, or AdNell-1+AdBMP-2 overexpression viruses. Effects were studied by cell morphology, alkaline phosphatase activity, osteopontin production, and MAPK signaling. Additionally, in a nude mouse model, viruses were injected into leg muscles, and new bone formation was examined after 2 and 8 wk. RESULTS: C2C12 myoblasts co-transduced with AdNell-1+AdBMP-2 showed a synergistic effect on osteogenic differentiation as detected by alkaline phosphatase activity and osteopontin production. Nell-1 stimulation on AdNell-1 + AdBMP-2 preconditioned C2C12 cells revealed significant activation of the non-BMP-2 associated c-Jun N-terminal kinase (JNK) MAPK signaling pathway, but not the p38 or extracellular signal-regulated kinase (ERK1/2) MAPK pathways. Importantly Nell-1 alone did not induce osteogenic differentiation of myoblasts. In a nude mouse model, injection of AdNell-1 alone stimulated no bone formation within muscle; however, injection of AdNell-1+AdBMP-2 stimulated a synergistic increase in bone formation compared with AdBMP-2 alone. CONCLUSIONS: These findings are important because of the confirmed osteochondral specificity of Nell-1 signaling and the potential therapeutic effects of enhanced BMP-2 action with coordinated Nell-1 delivery. 相似文献
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