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91.
Tunu Ramadhani Vanessa Short Mark A. Canfield D. Kim Waller Adolfo Correa Marjorie Royle Angela Scheuerle 《Birth defects research. Part A, Clinical and molecular teratology》2009,85(9):755-763
BACKGROUND: Literature on the risk of birth defects among foreign‐ versus U.S.–born Hispanics is limited or inconsistent. We examined the association between country of birth, immigration patterns, and birth defects among Hispanic mothers. METHODS: We used data from the National Birth Defects Prevention Study and calculated odds ratios (ORs) and 95% confidence intervals and assessed the relationship between mothers' country of birth, years lived in the United States, and birth defects among 575 foreign‐born compared to 539 U.S.–born Hispanic mothers. RESULTS: Hispanic mothers born in Mexico/Central America were more likely to deliver babies with spina bifida (OR = 1.53) than their U.S.–born counterparts. Also, mothers born in Mexico/Central America or who were recent United States immigrants (≤5 years) were less likely to deliver babies with all atrial septal defects combined, all septal defects combined, or atrial septal defect, secundum type. However, Hispanic foreign‐born mothers who lived in the United States for >5 years were more likely to deliver babies with all neural tube defects combined (OR = 1.42), spina bifida (OR = 1.89), and longitudinal limb defects (OR = 2.34). Foreign‐born mothers, regardless of their number of years lived in the United States, were more likely to deliver babies with anotia or microtia. CONCLUSIONS: Depending on the type of birth defect, foreign‐born Hispanic mothers might be at higher or lower risk of delivering babies with the defects. The differences might reflect variations in predisposition, cultural norms, behavioral characteristics, and/or ascertainment of the birth defects. Birth Defects Research (Part A), 2009. © 2009 Wiley‐Liss, Inc. 相似文献
92.
Victoria Cavaliere Daniela L Papademetrio Mario Lorenzetti Pamela Valva María Victoria Preciado Patricia Gargallo Irene Larripa Mariela B Monreal María Laura Pardo Silvia E Hajos Guillermo AC Blanco élida MC álvarez 《Translational oncology》2009,2(1):46-58
Chemotherapy aims to limit proliferation and induce apoptotic cell death in tumor cells. Owing to blockade of signaling pathways involved in cell survival and proliferation, nuclear factor κB (NF-κB) inhibitors can induce apoptosis in a number of hematological malignancies. The efficacy of conventional chemotherapeutic drugs, such as vincristine (VCR) and doxorubicine (DOX), may be enhanced with combined therapy based on NF-κB modulation. In this study, we evaluated the effect of caffeic acid phenylethyl ester (CAPE) and MG-132, two nonspecific NF-κB inhibitors, and conventional chemotherapeutics drugs DOX and VCR on cell proliferation and apoptosis induction on a lymphoblastoid B-cell line, PL104, established and characterized in our laboratory. CAPE and MG-132 treatment showed a strong antiproliferative effect accompanied by clear cell cycle deregulation and apoptosis induction. Doxorubicine and VCR showed antiproliferative effects similar to those of CAPE and MG-132, although the latter drugs showed an apoptotic rate two-fold higher than DOX and VCR. None of the four compounds showed cytotoxic effect on peripheral mononuclear cells from healthy volunteers. CAPE- and MG-132-treated bone marrow cells from patients with myeloid and lymphoid leukemias showed 69% (P < .001) and 25% decrease (P < .01) in cell proliferation and 42% and 34% (P < .01) apoptosis induction, respectively. Overall, our results indicate that CAPE and MG-132 had a strong and selective apoptotic effect on tumor cells that may be useful in future treatment of hematological neoplasias. 相似文献
93.
Kwok WK Picioreanu C Ong SL van Loosdrecht MC Ng WJ Heijnen JJ 《Biotechnology and bioengineering》1998,58(4):400-407
The influence of process conditions (substrate loading rate and detachment force) on the structure of biofilms grown on basalt particles in a Biofilm Airlift Suspension (BAS) reactor was studied. The structure of the biofilms (density, surface shape, and thickness) and microbial characteristics (biomass yield) were investigated at substrate loading rates of 5, 10, 15, and 20 kg COD/m3. day with basalt concentrations of 60 g/L, 150 g/L, and 250 g/L. The basalt concentration determines the number of biofilm particles in steady state, which is the main determining factor for the biofilm detachment in these systems. In total, 12 experimental runs were performed. A high biofilm density (up to 67 g/L) and a high biomass concentration was observed at high detachment forces. The higher biomass content is associated with a lower biomass substrate loading rate and therefore with a lower biomass yield (from 0.4 down to 0.12 gbiomass/gacetate). Contrary to general beliefs, the observed biomass detachment decreased with increasing detachment force. In addition, smoother (fewer protuberances), denser and thinner compact biofilms were obtained when the biomass surface production rate decreased and/or the detachment force increased. These observations confirmed a hypothesis, postulated earlier by Van Loosdrecht et al. (1995b), that the balance between biofilm substrate surface loading (proportional to biomass surface production rate, when biomass yield is constant) and detachment force determines the biofilm structure. When detachment forces are relatively high only a patchy biofilm will develop, whereas at low detachment forces, the biofilm becomes highly heterogeneous with many pores and protuberances. With the right balance, smooth, dense and stable biofilms can be obtained. Copyright 1998 John Wiley & Sons, Inc. 相似文献
94.
95.
Serruys P Grines C Stone G Garcia E Kiemeney F Morice M Sousa J Hamm C Costantini C Probst P Rutsch W Penn I Fernandez-Aviles F Vandormael M Bartorelli A Bilodeau L Eijgelshoven M 《International journal of cardiovascular interventions》1998,1(1):19-27
Preliminary experience with primary stenting in myocardial infarction has suggested a greater benefit in clinical outcome than has been obtained with direct balloon angioplasty. However, subacute thrombosis (SAT) remains a limitation for this new mode of therapy. In the BENESTENT II Pilot and main trials, the incidence of SAT with the heparin-coated Palmaz-Schatz stent was only 0.15%. Therefore, as a preamble to a large randomized trial, the feasibility and safety of the use of the Heparin-Coated Palmaz-Schatz trade mark Stent in Acute Myocardial Infarction (AMI) was tested in 101 patients enrolled between April and September 1996 in 18 clinical centres. In 101 stent-eligible AMI patients, as dictated by protocol, a heparin-coated stent was implanted. The primary objectives were to determine the in-hospital incidence of major adverse cardiac events (MACE: death, MI, target lesion revascularization) and bleeding complications, while the secondary objectives were the procedural success rate and the MACE, the restenosis and reocclusion rates at 6.5 months. Stent implantation (n 3 129 stents) was successful in 97 patients of the 101 who were included in this trial. During their hospital stay, two patients died and no patient experienced re-infarction, ischaemia prompting re-PTCA or CABG. Four patients suffered a bleeding complication, three major and one minor, of whom three required surgical repair. At 210 days follow-up, 81% of the patients were event free. At 6.5 months restenosis was documented in 18% of the 88 patients who underwent follow-up angiography, including three total occlusions. The results, both with respect to QCA and the occurrence of MACE, compare favourably with studies using elective stenting in both stable and unstable angina patients. As a result of this pilot study, a large randomized trial comparing direct balloon angioplasty with direct stenting in 900 patients with AMI was initiated in December 1996. 相似文献
96.
Nucleotide sequence of the D-loop region of the sperm whale (Physeter macrocephalus) mitochondrial genome 总被引:4,自引:0,他引:4
We have amplified, by the polymerase chain reaction, and have sequenced the
D-loop region of the mitochondrial DNA from the sperm whale (Physeter
macrocephalus). The sperm whale D-loop was aligned with D- loop sequences
from four other cetaceans (Commerson's dolphin, orca, fin whale, and minke
whale) and an out-group (cow). This alignment showed the sperm whale
sequence to be larger than that of other cetaceans. In addition, some
sequence blocks were highly conserved among all six species, suggesting
roles in the functioning of mitochondrial DNA. Other blocks that were
previously reported to be well conserved among cetaceans showed little
sequence conservation with the sperm whale D-loop, which argues against the
functional importance of these sequence blocks in cetaceans.
相似文献
97.
98.
Zimmerman PA; Katholi CR; Wooten MC; Lang-Unnasch N; Unnasch TR 《Molecular biology and evolution》1994,11(3):384-392
Polymerase chain reaction (PCR) products were characterized for a repeated
sequence family (designated "O-150") of the human filarial parasite
Onchocerca volvulus. In phylogenetic inferences, the O-150 sequences
clustered into closely related groups, suggesting that concerted evolution
maintains sequence homology in this family. Using a novel mathematical
model based on a nested application of an analysis of variance, we
demonstrated that African rainforest and savannah strain parasite
populations are significantly different. In contrast, parasites collected
in the New World are indistinguishable from African savannah strains of O.
volvulus. This finding supports the hypothesis that onchocerciasis was
recently introduced into the New World, possibly as a result of the slave
trade.
相似文献
99.
Angela Scheuerle Vani X. Vannappagari Mary K. Miller 《Birth defects research. Part A, Clinical and molecular teratology》2009,85(7):611-620
Pharmaceutical pregnancy registries document birth defects and other complications reported in pregnancies exposed to specific medications or diseases. A baseline estimate of birth defect prevalence is necessary for comparison. To identify potential teratogenic signals, the pregnancy registry must have a comparator that most closely matches the exposed population and data collection methodology, which are characteristics that vary among the multiplicity of birth defect surveillance systems. The system that yields the most accurate prevalence data may be different from that most closely matching the pregnancy registry methods. State public health programs have highly accurate and precise statistics, but their populations are broader than those of a pharmaceutical pregnancy registry. Large collaborative databases may have a more useful covered population, but there are secondary problems related to data precision. Health care databases enroll large numbers of patients and have good information about exposures and health problems, but the data can be difficult to access and lack useful detail. Exposure‐related databases are closer in population definition and collection methods, though the presence of different diseases and exposures can be problematic. Internal comparators are likely to be most useful in formal statistical analysis, but added cost and management burden and may require significantly increased registry enrollment. There is no ideal comparator, and this must be taken into account when planning a single‐exposure or single‐disease pregnancy registry. Birth Defects Research (Part A), 2009. © 2009 Wiley‐Liss, Inc. 相似文献
100.