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81.
Physiology of the lateral decubitus position and one-lung ventilation   总被引:18,自引:0,他引:18  
OLV is most frequently utilized to provide a quiet field for the performance of many different surgical procedures. In some patients, severe hypoxemia may result, mandating the implementation of other therapies to provide adequate oxygenation. This paper has reviewed the physiological consequences of the lateral position that may contribute to the hypoxemia and the techniques we utilize at our institution for establishing OLV, maintaining OLV, and treating hypoxemia during OLV. Our technique is performed with the goal of maintaining adequate gas exchange and protecting the ventilated lung from potential overdistension and injury. It remains for future study to determine if the use of a lung protective strategy during intraoperative OLV offers any benefit to patients at risk for postoperative lung injury, such as those undergoing major lung resections.  相似文献   
82.
PURPOSE: We sought to elucidate long-term changes in health-related quality-of-life (HRQOL) outcomes by prospectively re-evaluating a well-characterized cohort of prostate cancer (PC) survivors 4 to 8 years after primary treatment. PATIENTS AND METHODS: Patients who had been evaluated previously at a median of 2.6 years after radical prostatectomy (RP), external radiation (three-dimensional conformal radiation therapy [3-D CRT]), or brachytherapy (BT) were recontacted at a median of 6.2 years after treatment. The clinical relevance of long-term HRQOL impairment among survivors was established by comparison with controls of similar age. Factors associated with HRQOL changes during this interval were evaluated. RESULTS: Of the 964 eligible men, 709 (73.5%) completed measurable questionnaires. In four domains (urinary irritative-obstructive, urinary incontinence, bowel, and sexual), significant HRQOL differences were detected for at least one of the therapy groups, compared with controls (all P < .05). During the 4-year interval, significant improvement was observed for the urinary irritative-obstructive (P < .0001) and bowel (P < .0001) domains among BT patients, whereas urinary incontinence HRQOL worsened for both the BT (P = .0017) and 3-D CRT (P = .0008) treatment groups. Overall sexual HRQOL deteriorated for the 3-D CRT cohort (P = .0017), as well as for controls (P = .0136). Among RP patients, significant HRQOL changes were not observed. CONCLUSION: During a 4-year interval from earlier to longer-term phases of PC treatment survivorship, sexual, urinary, and bowel dysfunction remain significant concerns among early-stage PC treatment survivors, compared with control men. Although postprostatectomy HRQOL remains relatively stable during this interval, disease-specific HRQOL continues to evolve among men treated with BT and 3-D CRT.  相似文献   
83.
84.
Over a 1-year period, seven eclamptic patients with repetitive seizures while receiving therapeutic levels of intravenous magnesium sulfate were evaluated by computerized axial tomography. In five patients brain abnormalities were identified, which included diffuse cerebral edema (one), cerebral venous thrombosis (two), and low density white matter (two). Clinical management of eclamptic women on the basis of structural central nervous system abnormalities documented by computerized tomography appears to warrant further investigation.  相似文献   
85.
Pre-eclampsia (PE) is a multi-system disorder of pregnancy hypothesised to arise from circulating factors derived from an unhealthy placenta. Some changes in placental phenotype seen in PE can be reproduced by culture in altered oxygen (O(2)) tension. Currently, these circulating factors are unidentified, partly due to the complexity of maternal plasma. Investigation of factors released from placental tissue provides a potential method to identify bioactive compounds. Experimental strategies to study compounds present in a biological system have expanded greatly in recent years. Metabolomics can detect and identify endogenous and secreted metabolites. We aimed to determine whether metabolites could be identified in placental cultures with acceptable experimental variability and to determine whether altered O(2) tension affects the composition of the placental metabolome. In this study we used gas-chromatography-mass spectroscopy to determine the presence of metabolites in conditioned culture medium (CCM) and tissue lysates of placental villous explants cultured in 1, 6 and 20% atmospheric O(2) for 96h. This experimental strategy had an intra-assay variation of 6.1-11.6%. Intra and inter-placental variability were 15.7-35.8% and 44.8-46.2% respectively. Metabolic differences were identified between samples cultured in 1, 6 and 20% O(2) in both CCM and tissue lysate. Differentially expressed metabolites included: 2-deoxyribose, threitol or erythritol and hexadecanoic acid. We conclude that metabolomic strategies offer a novel approach to investigate placental function. When conducted under carefully controlled conditions, with appropriate statistical analysis, metabolic differences can be identified in placental explants in response to altered O(2) tension. Metabolomics could be used to identify changes in conditions associated with placental pathology.  相似文献   
86.
BackgroundMeningiomas are the most common primary intracranial tumor in adults. Clinical care is currently guided by the World Health Organization (WHO) grade assigned to meningiomas, a 3-tiered grading system based on histopathology features, as well as extent of surgical resection. Clinical behavior, however, often fails to conform to the WHO grade. Additional prognostic information is needed to optimize patient management.MethodsWe evaluated whether chromosomal copy-number data improved prediction of time-to-recurrence for patients with meningioma who were treated with surgery, relative to the WHO schema. The models were developed using Cox proportional hazards, random survival forest, and gradient boosting in a discovery cohort of 527 meningioma patients and validated in 2 independent cohorts of 172 meningioma patients characterized by orthogonal genomic platforms.ResultsWe developed a 3-tiered grading scheme (Integrated Grades 1-3), which incorporated mitotic count and loss of chromosome 1p, 3p, 4, 6, 10, 14q, 18, 19, or CDKN2A. 32% of meningiomas reclassified to either a lower-risk or higher-risk Integrated Grade compared to their assigned WHO grade. The Integrated Grade more accurately identified meningioma patients at risk for recurrence, relative to the WHO grade, as determined by time-dependent area under the curve, average precision, and the Brier score.ConclusionWe propose a molecularly integrated grading scheme for meningiomas that significantly improves upon the current WHO grading system in prediction of progression-free survival. This framework can be broadly adopted by clinicians with relative ease using widely available genomic technologies and presents an advance in the care of meningioma patients.  相似文献   
87.
New and emerging fish and shellfish diseases represent an important constraint to the growth and sustainability of many aquaculture sectors and have also caused substantial economic and environmental impacts in wild stocks. This paper details the results of 8 years of a monitoring programme for emerging aquatic animal diseases reported around the world. The objectives were to track global occurrences and, more specifically, to identify and provide advanced warning of disease threats that may affect wild and farmed fish stocks in the UK. A range of electronic information sources, including Internet newsletters, alerting services and news agency releases, was systematically searched for reports of new diseases, new presentations of known pathogens and known diseases occurring in new geographic locations or new host species. A database was established to log the details of key findings, and 250 emerging disease events in 52 countries were recorded during the period of study. These included 14 new diseases and a further 16 known diseases in new species. Viruses and parasites accounted for the majority of reports (55% and 24%, respectively), and known diseases occurring in new locations were the most important emerging disease category (in which viruses were dominant). Emerging diseases were reported disproportionally in salmonid species (33%), in farmed populations (62%) and in Europe and North America (80%). The lack of reports from some regions with significant aquaculture or fishery production may indicate that emerging diseases are not being recognized in these areas owing to insufficient surveillance or testing or that these events are being under‐reported. The results are discussed in relation to processes underpinning disease emergence in the aquatic environment.  相似文献   
88.
89.
The Selenium and Vitamin E Cancer Prevention Trial (SELECT) was conducted to assess the efficacy of selenium and vitamin E alone, and in combination, on the incidence of prostate cancer. This randomized, double-blind, placebo-controlled, 2 × 2 factorial design clinical trial found that neither selenium nor vitamin E reduced the incidence of prostate cancer after seven years and that vitamin E was associated with a 17% increased risk of prostate cancer compared to placebo. The null result was surprising given the strong preclinical and clinical evidence suggesting chemopreventive activity of selenium. Potential explanations for the null findings include the agent formulation and dose, the characteristics of the cohort, and the study design. It is likely that only specific subpopulations may benefit from selenium supplementation; therefore, future studies should consider the baseline selenium status of the participants, age of the cohort, and genotype of specific selenoproteins, among other characteristics, in order to determine the activity of selenium in cancer prevention.  相似文献   
90.
Objective. We were aware of a small number of cases in our EMS system where patients in respiratory distress had a worsening of their condition after being removed from the home on a Reeves® stretcher (RS). We sought to determine if this prehospital lifting device causes additional respiratory effort used in normal subjects by describing changes in heart rate, pulse oximetry, tidal volume, minute ventilation, andrespiratory rate. Methods. Forty-nine subjects were entered into this study. Data were collected while the subject was supine on the floor in the RS andonce while suspended over the floor in the device. A randomized crossover design was used. Ten subjects were excluded because of inadvertent omission of a nose plug during spirometry. Data points were recorded in the final minute of a 3-minute exposure. Three minutes was chosen to simulate a prehospital transport time from the scene to the ambulance. Minute ventilation, tidal volume, heart rate, pulse oximetry, andrespiratory rate were recorded for each subject during each phase. Subjects were also asked to rate the difficulty of breathing using the modified Borg scale. Results. Data were obtained for 39 subjects. The mean respiratory rate while suspended was 9.9 ± 3.0 breaths per minute compared to 9.1 ± 2.5 breaths per minutes supine on the floor (p = 0.007). The mean minute ventilation while suspended in a RS was 8.17 ± 3.25 L/min versus 7.37 ± 2.37 while lying flat (p = 0.03). There was no difference in tidal volume, heart rate, pulse oximetry, or subjective modified Borg scale ratings. Conclusions. Subjects suspended in a RS for 3 minutes had statistically higher respiratory rates andminute ventilation than the same subjects lying flat. Although these modest changes are clinically insignificant in normal subjects, they could present a significant challenge to subjects in respiratory distress.  相似文献   
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