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1.
Neuropathological examinations were carried out at necropsy on 274 cases of intrauterine death or neonatal death at or before three days after birth. Fifty six (20.4%) subjects had evidence of prenatal ischaemic brain damage. On review of the maternal case notes to ascertain antenatal clinical associations there was an increased incidence of intrauterine growth retardation, either based on birth weight for gestational age (odds ratio (OR) 2.0; 95% confidence interval (CI) 1.1 to 3.7) or diagnosed antenatally (OR 2.7; 95% CI 1.3 to 5.6). Oligohydramnios was also more common (OR 2.9; 95% CI 1.2 to 7.0). The association of intrauterine growth retardation and white matter damage remained after excluding fetuses with a major congenital anomaly (OR 2.4; 95% CI 1.1 to 5.1). The findings suggest that chronic intrauterine hypoxia may be associated with damage to cerebral white matter among fetuses and infants who die. The relation between ischaemic white matter damage and cerebral palsy among survivors remains speculative.  相似文献   
2.
The evolution of the web has outpaced itself: A growing wealth of information and increasingly sophisticated interfaces necessitate automated processing, yet existing automation and data extraction technologies have been overwhelmed by this very growth. To address this trend, we identify four key requirements for web data extraction, automation, and (focused) web crawling: (1) interact with sophisticated web application interfaces, (2) precisely capture the relevant data to be extracted, (3) scale with the number of visited pages, and (4) readily embed into existing web technologies. We introduce OXPath as an extension of XPath for interacting with web applications and extracting data thus revealed—matching all the above requirements. OXPath’s page-at-a-time evaluation guarantees memory use independent of the number of visited pages, yet remains polynomial in time. We experimentally validate the theoretical complexity and demonstrate that OXPath’s resource consumption is dominated by page rendering in the underlying browser. With an extensive study of sublanguages and properties of OXPath, we pinpoint the effect of specific features on evaluation performance. Our experiments show that OXPath outperforms existing commercial and academic data extraction tools by a wide margin.  相似文献   
3.
Life-cycle inventories were compiled to characterize natural resource requirements and environmental emissions associated with the sourcing and production of selected, detergent-grade surfactants and surfactant feedstocks. Petrochemical surfactant types examined were linear alkylbenzene sulfonate, alcohol sulfate (AS), alcohol ethoxylate (AE) and alcohol ethoxylate sulfate (AES). Oleochemical surfactants derived from palm oil, palm kernel oil and inedible tallow were AS, AE, AES and (for palm oil and tallow) methyl ester sulfonate. It was determined that natural resource requirements were primarily related to the source of feedstock and secondarily to surfactant type. Likewise, the composition and mass of atmospheric, aqueous and solid emissions were principally determined by feedstock source. Energy requirements varied as a function of both feedstock and surfactant type. The inventories do not support fundamental shifts in surfactant usage or feedstock sourcing on the basis of environmental concerns, as no single surfactant or feedstock was identified as superior across all resource and emissions criteria examined. The data provide baselines for evaluating opportunities for resource optimization, pollution prevention and waste minimization within each production technology surveyed.  相似文献   
4.
Abstract

Context: Aerosol delivery to animals in preclinical settings has historically been very challenging, requiring the use of techniques, such as intratracheal instillation and dry powder insufflation, that are somewhat invasive, inefficient and not representative of clinical inhalation.

Objective: The objective of this work is to develop a system to deliver dry powder to dogs in an efficient and effective manner for the study of new anti-migraine compounds in development.

Materials and methods: The new device uses a metered aliquot of a dry gas to force dry powder drug from a pre-filled HPMC capsule into an AeroChamber® spacer for subsequent inhalation by the animal.

Results: The delivery of two invesigational migraine drugs via the new device was assessed in vitro using abbreviated Andersen cascade impaction and showed the device is capable of generating a reproducible delivered dose of up to ~68% with more than 50% of the dose in the respirable range. In vivo studies have also been performed showing that this device effectively delivered the migraine drugs to spontaneously breathing dogs using a proprietary validated dog inhalation model.

Discussion: Results confirmed that the air pressurized capsule device (APCD) was effective in delivering the APIs to lungs of the animals. The in vivo data verified the advantages of inhaled delivery over oral delivery for this class of drugs and were used to establish the cardiopulmonary and respiratory side effect liability profile for these compounds.

Conclusions: This work has demonstrated the utility of this device for quick and accurate screening of prospective drug candidates, representing a significant improvement in ease of use and reprodicibility over current delivery methods.  相似文献   
5.
Inheritance of a major susceptibility gene for breast cancer has been primarily investigated in families with early-onset disease. However, familial clustering of late-onset breast cancer is well documented, and genetic factors may also be relevant. In the Iowa Women's Health Study, we evaluated evidence for a major gene after allowing for measured environmental risk factors. Two hundred sixty-five incident breast cancer probands were identified from a prospective cohort study of 41,837 women aged 55 to 69 years at baseline in 1986. A pedigree development form was mailed to the probands to ascertain all first-degree female relatives. A questionnaire and body measurement protocol were mailed to identified living relatives or surrogates. Segregation analyses were conducted on a total of 1,145 women in 251 families using regressive models as implemented in S.A.G.E. Mendelian codominant inheritance of an allele that produced an earlier-age-at-onset provided the best fit to the data. Incorporation of measured environmental risk factors as covariates yielded no significant improvements in the likelihoods. Approximately 50% of this population could be expected to carry a late-onset breast cancer susceptibility gene, and 23% of the population is susceptible because of the environment in which they live. Homozygous gene carriers are predicted to have a mean age-at-onset of 48 years, over 20 years earlier than heterozygotes; few cases would be expected among non-gene carriers. In conclusion, the transmission pattern of late-onset breast cancer may be determined by a common susceptibility gene.  相似文献   
6.
The possibility of primitive hematopoietic cell ex vivo expansion is of interest for both gene therapy and transplantation applications. The engraftment of autologous rhesus peripheral blood (PB) progenitors expanded 10 to 14 days were tracked in vivo using genetic marking. Stem cell factor (SCF)/granulocyte colony-stimulating factor (G-CSF)-mobilized and CD34-enriched PB cells were divided into two equal aliquots and transduced with one of two retroviral vectors carrying the neomycin-resistance gene (neo) for 4 days in the presence of interleukin-3 (IL-3), IL-6, and SCF in the first 5 animals, IL-3/IL-6/SCF/Flt-3 ligand (FLT) in 2 subsequent animals, or IL-3/IL-6/SCF/FLT plus an autologous stromal monolayer (STR) in the final 2. At the end of transduction period, one aliquot (nonexpanded) from each animal was frozen, whereas the other was expanded under the same conditions but without vector for a total of 14 days before freezing. After total body irradiation, both the nonexpanded and expanded transduced cells were reinfused. Despite 5- to 13-fold higher cell and colony-forming unit (CFU) doses from the expanded fraction of marked cells, there was greater short- and long-term marking from the nonexpanded cells in all animals. In animals receiving cells transduced and expanded in the presence of IL-3/IL-6/SCF/FLT, engraftment by the marked expanded cells was further diminished. This discrepancy was even more pronounced in the animals who received cells transduced and expanded in the presence of FLT and autologous stroma, with no marking detectable from the expanded cells. Despite lack of evidence for expansion of engrafting cells, we found that the addition of FLT and especially STR during the initial brief transduction period increased engraftment with marked cells into a clinically relevant range. Levels of marked progeny cells originating from the nonexpanded aliqouts were significantly higher than that seen in previous 4 animals receiving cells transduced in the presence of IL-3/IL-6/SCF, with levels of 10% to 20% confirmed by Southern blotting from the nonexpanded IL-3/IL-6/SCF/FLT/STR graft compared with 0.01% in the original IL-3/IL-6/SCF cohort. These results suggest that, although expansion of PB progenitors is feasible ex vivo, their contribution towards both short- and long-term engraftment is markedly impaired. However, a brief transduction in the presence of specific cytokines and stromal support allows engraftment with an encouraging number of retrovirally modified cells.  相似文献   
7.
8.
Eleven patients with chronic renal failure and presumed secondary hyperparathyroidism developed a syndrome of medial calcinosis of the arteries and painful ischemic ulcers of the fingers, legs, or thighs, or any combination of the three. Five patients required maintenance hemodialysis; six had functioning renal homografts. Severe hyperphosphatemia had existed in each; seven showed roentgenographic evidence of subperiosteal resorption. Similarities are evident between the lesions and experimentally produced calciphylaxix. The lesions demonstrated a relentless, progressive course, with serious morbidity and mortality. Hyperplastic or adenomatours parathyroid tissue was removed from ten of 11 patients unergoing surgical procedures; healing followed in seven patients. Treatment with phosphate-binding antacids to lower serum phosphorus levels may prevent this syndrome. Total or subtotal parathyroidectomy should be considered when ischemic skin lesions appear in uremic patients or in renal transplant recipients.  相似文献   
9.
Volumetric strain can be divided into two parts: strain due to bond distance change and strain due to vacancy sources and sinks. In this paper, efforts are focused on studying the atomic lattice strain due to a vacancy in an FCC metal lattice with molecular dynamics simulation (MDS). The result has been compared with that from a continuum mechanics method. It is shown that using a continuum mechanics approach yields constitutive results similar to the ones obtained based purely on molecular dynamics considerations.  相似文献   
10.
InAs/AlAsxSb1 − x quantum wells are investigated for their potential as hot carrier solar cells. Continuous wave power and temperature‐dependent photoluminescence indicate a transition in the dominant hot carrier relaxation process from conventional phonon‐mediated carrier relaxation below 90 K to a regime where inhibited radiative recombination dominates the hot carrier relaxation at elevated temperatures. At temperatures below 90 K, photoluminescence measurements are consistent with type‐I quantum wells that exhibit hole localization associated with alloy/interface fluctuations. At elevated temperatures, hole delocalization reveals the true type‐II band alignment, where it is observed that inhibited radiative recombination due to the spatial separation of the charge carriers dominates hot carrier relaxation. This decoupling of phonon‐mediated relaxation results in robust hot carriers at higher temperatures, even at lower excitation powers. These results indicate type‐II quantum wells offer potential as practical hot carrier systems. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
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