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51.
D J Brock 《Human heredity》1976,26(6):401-408
Measurement of beta-lipoprotein concentration in amniotic fluid is introduced as a new parameter for the early prenatal diagnosis of spina bifida. It was successful in 15 cases of spinal bifida, but failed in 5 cases of open spina bifida and 2 cases of closed spina bifida. All assays were performed before the end of the second trimester and most between 15 and 20 weeks of pregnancy. beta-lipoprotein was compared with alpha-fetoprotein and alpha2-macroglobulin in its effectiveness in diagnosing spina bifida at an early enough date to allow a termination of pregnancy. 相似文献
52.
Friedrich Brock 《Development genes and evolution》1927,112(1):204-238
Ohne ZusammenfassungHerr C.Vrieslander zeichnete in uneigennütziger Weise alle Abbildungen dieser Arbeit, welche durch Herrn Dr.Schulz von der Kulturabteilung der Universum-Filmgesellschaft nach meinen Angaben kinematographiert worden waren. 相似文献
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55.
J.R. Brock G.K. Bielmyer 《Comparative biochemistry and physiology. Toxicology & pharmacology : CBP》2013,158(3):150-158
The marine environment is subjected to contamination by a complex mixture of metals from various anthropogenic sources. Measuring the biological responses of organisms to a complex mixture of metals allows for examination of metal-specific responses in an environmentally realistic exposure scenario. To address this issue, the sea anemone, Aiptasia pallida was exposed to a control and a metal mixture (copper, zinc, nickel, and cadmium) at three exposure levels (10, 50, and 100 μg/L) for 7 days. Anemones were then transferred to metal-free seawater for an additional 7 days after the metal exposure to assess metal depuration and recovery. Metal accumulation, activity of the enzymes catalase, glutathione reductase, and carbonic anhydrase, as well as, cell density of the symbiotic zooxanthellae were measured over 14 days. Metal accumulation in A. pallida occurred in a concentration dependent manner over the 7-day exposure period. Altered enzyme activity and tentacle retraction of the host, as well as decreased zooxanthellae cell density were observed responses over the 7 days, after exposure to a metal concentration as low as 10 μg/L. Metal depuration and physiological recovery were dependent on both the metal and the exposure concentration. Understanding how A. pallida and their symbionts are affected by metal exposures in the laboratory may allow better understanding about the responses of symbiotic cnidarians in metal polluted aquatic environments. 相似文献
56.
Hilda T. Draeger Shervin Assassi Roozbeh Sharif Emilio B. Gonzalez Brock E. Harper Frank C. Arnett Ameena Manzoor Richard A. Lange Maureen D. Mayes 《PloS one》2013,8(10)
Objective
To evaluate the prognostic significance of baseline electrocardiogram (ECG) abnormalities in a multiethnic cohort of patients with early systemic sclerosis (SSc) and to determine the serological, clinical, and echocardiogram correlates of ECG findings.Methods
SSc patients with disease duration of≤5 years were enrolled in the GENISOS (Genetics versus Environment in Scleroderma Outcome Study) cohort. At the first visit, a standard 12 lead ECG was obtained along with demographic information, clinical data, and autoantibodies. The results of echocardiograms were also recorded. All ECGs were interpreted by a cardiologist unaware of the patients'' clinical data.Results
Of 265 SSc patients with average disease duration at enrollment of 2.5 years, 140 (52.8%) had abnormal ECG findings. These findings were not associated with SSc disease type or autoantibody profile but were associated with more severe heart and lung involvement. A total of 75 patients (28.3%) died over a follow up time of 9.9 years. Complete right bundle branch block (± left anterior hemiblock) on ECG, present in 7 (2.6%) patients, predicted a higher risk of mortality (HR: 5.3; 95% CI: 2.1 to 13.4; p<0.001). The predictive significance of right bundle branch block was independent of age at enrollment, gender, ethnicity and risk factors for coronary artery disease.Conclusion
ECG abnormalities are common in patients with early SSc and are associated with the severity of lung and heart involvement. Right bundle branch block is an independent predictor of mortality, and should be considered a marker of disease severity in SSc. 相似文献57.
Devin C Koestler Brock C Christensen Margaret R Karagas Carmen J Marsit Scott M Langevin Karl T Kelsey John K Wiencke E Andres Houseman 《Epigenetics》2013,8(8):816-826
The potential influence of underlying differences in relative leukocyte distributions in studies involving blood-based profiling of DNA methylation is well recognized and has prompted development of a set of statistical methods for inferring changes in the distribution of white blood cells using DNA methylation signatures. However, the extent to which this methodology can accurately predict cell-type proportions based on blood-derived DNA methylation data in a large-scale epigenome-wide association study (EWAS) has yet to be examined. We used publicly available data deposited in the Gene Expression Omnibus (GEO) database (accession number GSE37008), which consisted of both blood-derived epigenome-wide DNA methylation data assayed using the Illumina Infinium HumanMethylation27 BeadArray and complete blood cell (CBC) counts among a community cohort of 94 non-diseased individuals. Constrained projection (CP) was used to obtain predictions of the proportions of lymphocytes, monocytes and granulocytes for each of the study samples based on their DNA methylation signatures. Our findings demonstrated high consistency between the average CBC-derived and predicted percentage of monocytes and lymphocytes (17.9% and 17.6% for monocytes and 82.1% and 81.4% for lymphocytes), with root mean squared error (rMSE) of 5% and 6%, for monocytes and lymphocytes, respectively. Similarly, there was moderate-high correlation between the CP-predicted and CBC-derived percentages of monocytes and lymphocytes (0.60 and 0.61, respectively), and these results were robust to the number of leukocyte differentially methylated regions (L-DMRs) used for CP prediction. These results serve as further validation of the CP approach and highlight the promise of this technique for EWAS where DNA methylation is profiled using whole-blood genomic DNA. 相似文献
58.
Wenji Yan Kongming Wu James G Herman Malcolm V Brock Fran?ois Fuks Lili Yang Hongbin Zhu Yazhuo Li Yunsheng Yang Mingzhou Guo 《Epigenetics》2013,8(12):1373-1383
Colorectal cancer (CRC) is one of the common malignant tumors worldwide. Both genetic and epigenetic changes are regarded as important factors of colorectal carcinogenesis. Loss of DACH1 expression was found in breast, prostate, and endometrial cancer. To analyze the regulation and function of DACH1 in CRC, 5 colorectal cancer cell lines, 8 cases of normal mucosa, 15 cases of polyps and 100 cases of primary CRC were employed in this study. In CRC cell lines, loss of DACH1 expression was correlated with promoter region hypermethylation, and re-expression of DACH1 was induced by 5-Aza-2'-deoxyazacytidine treatment. We found that DACH1 was frequently methylated in primary CRC and this methylation was associated with reduction in DACH1 expression. These results suggest that DACH1 expression is regulated by promoter region hypermethylation in CRC. DACH1 methylation was associated with late tumor stage, poor differentiation, and lymph node metastasis. Re-expression of DACH1 reduced TCF/LEF luciferase reporter activity and inhibited the expression of Wnt signaling downstream targets (c-Myc and cyclinD1). In xenografts of HCT116 cells in which DACH1 was re-expressed, tumor size was smaller than in controls. In addition, restoration of DACH1 expression induced G2/M phase arrest and sensitized HCT116 cells to docetaxel. DACH1 suppresses CRC growth by inhibiting Wnt signaling both in vitro and in vivo. Silencing of DACH1 expression caused resistance of CRC cells to docetaxel. In conclusion, DACH1 is frequently methylated in human CRC and methylation of DACH1 may serve as detective and prognostic marker in CRC. 相似文献
59.
Madelon Van de Kerk Brock R. McMillan Kent R. Hersey Annette Roug Randy T. Larsen 《The Journal of wildlife management》2020,84(4):813-820
Capture techniques to deploy radio-collars often risk mortality and injury to the animal. Capture-induced mortality can affect population sizes but also introduces bias in survival estimates based on data from captured animals. In recent years, a large-scale research and monitoring project in Utah, USA, has involved capturing and radio-collaring hundreds of mule deer (Odocoileus hemionus), a species of great interest in large parts of North America. Our objective was to investigate how the survival rates of these mule deer were affected by capture and handling. During winters of 2014–2018, an experienced capture crew net-gunned and fitted 1,805 animals with global positioning system (GPS)-collars. We estimated survival rates during the first 6 weeks after capture using Cox proportional hazard regression, and compared the survival rates of animals that were captured in a particular year to those of animals that were not captured but fitted with a GPS-collar in a previous year. We used a model selection framework to evaluate how long survival rates of captured animals were different from those of animals that were not captured. Our results indicated that weekly survival rates of captured animals were 0.985 ± 0.003 (SE), 0.988 ± 0.002, and 0.990 ± 0.001 in weeks 1, 2 and 3, respectively. Weekly survival rates of captured deer during weeks 4–6 were 0.993 ± 0.001, the same as those of deer that were not captured at the same time. Furthermore, post-capture survival rates were positively influenced by body size and negatively influenced by age. We conclude that the mortality resulting from helicopter capture was low but recommend comparing newly captured and previously captured individuals to examine what proportion of observed mortality is likely capture-related. © 2020 The Wildlife Society. 相似文献
60.
Bishop Tara B. B. Gill Richard A. McMillan Brock R. St. Clair Samuel B. 《Oecologia》2020,192(1):155-167
Oecologia - Biological invasions are responsive to changing wildfire regimes related to human activities that are altering biological communities. Our objective was to investigate how fire, rodent... 相似文献