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81.
82.
Millicent Ford Rauch Sara Royce Hynes James Bertram y Redmond Rebecca Robinson Cicely Williams Hao Xu Joseph A. Madri Erin B. Lavik 《The European journal of neuroscience》2009,29(1):132-145
Angiogenesis precedes recovery following spinal cord injury and its extent correlates with neural regeneration, suggesting that angiogenesis may play a role in repair. An important precondition for studying the role of angiogenesis is the ability to induce it in a controlled manner. Previously, we showed that a coculture of endothelial cells (ECs) and neural progenitor cells (NPCs) promoted the formation of stable tubes in vitro and stable, functional vascular networks in vivo in a subcutaneous model. We sought to test whether a similar coculture would lead to the formation of stable functional vessels in the spinal cord following injury. We created microvascular networks in a biodegradable two-component implant system and tested the ability of the coculture or controls (lesion control, implant alone, implant + ECs or implant + NPCs) to promote angiogenesis in a rat hemisection model of spinal cord injury. The coculture implant led to a fourfold increase in functional vessels compared with the lesion control, implant alone or implant + NPCs groups and a twofold increase in functional vessels over the implant + ECs group. Furthermore, half of the vessels in the coculture implant exhibited positive staining for the endothelial barrier antigen, a marker for the formation of the blood–spinal cord barrier. No other groups have shown positive staining for the blood–spinal cord barrier in the injury epicenter. This work provides a novel method to induce angiogenesis following spinal cord injury and a foundation for studying its role in repair. 相似文献
83.
Beatriz Luna Sara K Doll Stephen J Hegedus Nancy J Minshew John A Sweeney 《Neuropsychopharmacology》2007,61(4):474-481
BACKGROUND: Executive dysfunction has been reported at different ages in autism. It is not clear however, when this impairment emerges or how its expression is affected by development. METHODS: 61 non-mentally retarded autism participants (AUT) and 61 age, gender, and IQ matched typically developing participants (CON) were assessed with two oculomotor executive function tasks, the oculomotor delayed response task (ODR) and the antisaccade task (AS), as well as a visually-guided saccade sensorimotor task (VGS). RESULTS: The AUT group demonstrated impairments in response inhibition and spatial working memory at all ages tested. Developmental improvements in speed of sensorimotor processing and voluntary response inhibition were similar in both groups indicating sparing of some attentional control of behavior. Developmental progression in the speed of initiating a cognitive plan and maintaining information on line over time, however, was impaired in the AUT group indicating abnormal development of working memory. CONCLUSIONS: These results indicate that while executive dysfunction is present throughout development, there is evidence for both typical and atypical developmental progression of executive functions in autism. The plasticity suggested by the developmental improvements may have implications regarding appropriate developmental epochs and types of interventions aimed at enhancing cognitive capacities in individuals with autism. 相似文献
84.
Although breast milk is recommended as the optimal source of infant nutrition, breastfeeding initiation is below recommended levels, especially among teenage mothers. Breastfeeding initiation rates among Michigan (US) teenage mothers (12-19 y) were compared by demographics and health behaviors. Multivariate analyses determined which factors were significant independent predictors of breastfeeding initiation among teenage mothers enrolled prenatally in the Michigan Special Supplemental Nutrition Program for Women, Infants, and Children (WIC) program in 1995. Significant predictors independently associated with breastfeeding initiation were race/ethnicity, education, marital status, postpartum anemia status, parity, prenatal trimester of WIC enrollment, and smoking. The strongest predictor of breastfeeding initiation differed for white mothers (positive predictor: education beyond high school [OR = 3.13]) and black mothers (negative predictor: multiparous [OR = 0.25]). Initiation rates for this population of teenage mothers fall below the national average for mothers of all ages and the US Healthy People 2010 goals. Research is needed concerning how breastfeeding support and education can be improved to reach the US national health goals. 相似文献
85.
Juan Francisco Sánchez Muñoz-Torrero Paloma Barquilla Raul Velasco Maria del Carmen Fernández Capitan Nazaret Pacheco Lucia Vicente Jose Luis Chicón Sara Trejo Jose Zamorano Alicia Lorenzo Hernandez 《European journal of clinical pharmacology》2010,66(12):1257-1264
Objectives
This study was designed to assess the prevalence of adverse drug reactions (ADRs) in the internal medicine wards of two teaching Hospitals, identify the most common ADRs, the principal medications involved, and determine the risk factors implicated in the occurrence of such ADRs. 相似文献86.
Sara A. Mueting Shawn L. Gerstenberger 《Bulletin of environmental contamination and toxicology》2010,84(4):497-501
The recent invasion of the Dressenid species, the quagga mussel, Dreissena bugensis, into Lakes Mead, Mohave and Havasu has raised questions about their ability to alter contaminant cycling. Mussels were collected
from 25 locations in the three lakes. The overall average was 0.036 ± 0.016 μg g−1 Hg dry wt. The range of the three lakes was from 0.014–0.093 μg g−1 Hg dry wt. There were no significant differences in mercury concentrations among the three lakes (F = 0.07; p = 0.794). From this baseline data of contaminants in quagga mussels from the lower Colorado River, this species may be used
to biomonitor lake health. 相似文献
87.
Rolf Meier Eva Posern Georg Weitzmann 《Virchows Archiv : an international journal of pathology》1937,299(1-2):316-328
Ohne ZusammenfassungMit 10 Abbildungen im Text.Die Arbeit wurde ausgeführt mit Unterstützung der Lady Tata Memorial-Stiftung, der wir für die Ermöglichung unserer Arbeiten zu größtem Danke verpflichtet sind. 相似文献
88.
Katherine P Rankin Anli A Liu Sara Howard Hilary Slama Craig E Hou Karen Shuster Bruce L Miller 《Cognitive and behavioral neurology》2007,20(1):48-61
OBJECTIVE: To characterize dementia-induced changes in visual art production. BACKGROUND: Although case studies show altered visual artistic production in some patients with neurodegenerative disease, no case-controlled studies have quantified this phenomenon across groups of patients. METHOD: Forty-nine subjects [18 Alzheimer disease, 9 frontotemporal dementia (FTD), 9 semantic dementia (SD), 15 healthy older controls (NC)] underwent formal neuropsychologic testing of visuospatial, perceptual, and creative functioning, and produced 4 drawings. Subjective elements of drawings were rated by an expert panel that was blind to diagnosis. RESULTS: Despite equal performance on standard visuospatial tests, dementia groups produced distinct patterns of artistic features that were significantly different from NCs. FTDs used more disordered composition and less active mark-making (P<0.05). Both FTDs and SDs drawings were rated as more bizarre and demonstrated more facial distortion than NCs (P<0.05). Also, SDs drastically failed a standardized test of divergent creativity. Alzheimer disease artwork was more similar to controls than to FTDs or SDs, but showed a more muted color palette (P<0.05) and trends toward including fewer details, less ordered compositions, and occasional facial distortion. CONCLUSIONS: These group differences in artistic style likely resulted from disease-specific focal neurodegeneration, and elucidate the contributions of particular brain regions to the production of visual art. 相似文献
89.
Methods. To assess the occupational exposure of the anaesthetist to anaesthetic gases, a total of 1 German and 25 Swiss hospitals were investigated. A Brüel & Kjær Type 1302 multi-gas monitor was used to measure concentrations of nitrous oxide and halogenated anaesthetic agents in the anaesthetist's breathing zone. Measurements were performed during 114 general anaesthetic, 55 of which were in patients under 11 years of age. In these 55 patients, the influence of various factors on the exposure (time-weighted average concentrations) was estimated by comparing different data groups. The efficiency of the applied scavenging equipment was examined by surveying the exhalation valve with a leak detector (type TIF 5600, TIF Instruments, Miami). Results. Sessions with patients under 11 years of age revealed much higher anaesthetic gas exposures compared to older patients. The concentrations of nitrous oxide were on average threefold (Fig. 1), those of the halogenated anaesthetics fivefold higher (Fig. 2) for the younger patients. In 11- to 16-year-old patients the exposure level was the same as in adult patients. The measurements showed a reduction of 85% in exposure if an efficient scavenging system (i.e., no waste gas discharge to room air through the exhalation valve) or lower fresh gas flow were used (Fig. 4); 42% of the inspected scavengers were inefficient, and reduced the exposure on average by only 30%. In operating theatres with a ventilation rate of at least ten air changes per h, the measured concentrations of anaesthetic gases in the inhalation zone of the anaesthetists were reduced more than 50% compared to poorly ventilated rooms (Figs. 4 and 5). The use of tracheal intubation or laryngeal mask airway (LMA) anaesthesia resulted in a reduction of 80% in exposure compared to standard face masks if efficient scavenging was used. The exposures during sessions with inefficiently scavenged Bain coaxial systems or unscavenged semi-open delivery systems of the Jackson-Rees type were tenfold higher than with scavenged rebreathing circuit systems (Fig. 6). During anaesthesia with IV or double-mask induction, the average levels of inhalation anaesthetics were reduced by about 80% compared to inhalational induction with standard masks (Fig. 7). The anaesthetist's working technique is a very important factor that strongly influences the concentrations. Poor work practices, like lifting off the face mask with anaesthetic gas flow turned on, increased the exposure of the anaesthetist and other operating room personnel drastically, even if the other conditions (scavenger and room ventilation) were good. Discussion. The exposure levels of anaesthetic gases are generally higher during anaesthesia in children up to 10 years of age than in older patients. Nevertheless, the measurements showed that exposure during paediatric anaesthesia can be kept below the recommended limit (8-h TWA in Switzerland) of 100 ppm nitrous oxide and 5 ppm halothane or 10 ppm enflurane or isoflurane. Causes of high exposures were particularly high fresh gas flows often applied without scavenging or together with inefficient scavenging devices and the high part of mask anaesthesia and inhalation induction with a loosely held mask. To achieve an effective reduction of occupational exposure, well-adjusted and maintained scavenging systems and low-leakage work practices are of primary importance. As leakage can never be completely avoided, a ventilation rate of at least ten air changes per h should be maintained in operating rooms and rooms where anaesthesia is induced to keep down concentrations of waste anaesthetic gases. High exposure during mask anaesthesia and inhalation induction can be prevented by further measures. Using a LMA instead of a standard mask reduces the exposure to the same level as endotracheal intubation. The exposure during induction can be reduced remarkably by the use of the double-mask system or IV induction. Applying low fresh gas flows reduces not only the exposure concentrations in the theatres, but also the contribution to the environmental burden (`?greenhouse effect?' and ozone layer destruction). 相似文献
90.
A chronic coronary occlusion consists of an atherosclerotic plaque and one or several thrombi. It clinically imitates a tight stenosis but is exempt from the risk of truly unstable angina or myocardial infarction. Hence, quality of life is at stake and not longevity. This holds true for balloon angioplasty as well as for surgery. Indications for angioplasty are based on an estimate of technical difficulties and clinical risks balanced against potential subjective benefit and amount of viable myocardium concerned. An occlusion flush at the orifice of the vessel, tapering into a small sidebranch, with bridging collaterals, or devoid of collaterals is no target for angioplasty. Primary success is around 65% and complications are extremely rare. Abrupt vessel closure is common but harmless. No Q-wave infarctions have been reported in that context. The need for emergency bypass surgery may arise from acute closure of a vessel proximal to the occlusion in an exceptional case. Duration and length of occlusion are the most important predictors of success. Recurrence averages 62% (17% reocclusion and 45% restenosis). An important factor for the high recurrence rate is the competitive pressure exerted by the collaterals on standby. Recurrence happens almost exclusively within the first six months. It is innocuous but produces symptoms prompting further interventions (repeat angioplasty or bypass surgery). The conventional technique uses a stiff guidewire and advances the balloon catheter close to the tip of the guidewire for additional rigidity. New technologies are under investigation but no breakthrough has happened so far. They encompass blunt mechanical instruments (e.g., Magnum wire), drills of various velocities, laser energy applied directly to the tissue (some angioscopically guided, some triggered by on-line spectral tissue analysis), catheters dispersing laser energy through a sapphire or converting it into heat (hot tip), and electrical or radiofrequency heat applicators. As low-yield procedures had better be low-risk and low-cost, there are definite limits to how sophisticated, complicated, risky, and expensive tools and techniques for percutaneous coronary recanalization can become. Close relatives of conventional gear such as the Magnum system offer themselves as first choice equipment complemented, in case of need, by mechanical drills. 相似文献