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321.
An independent clinical assessment was compared with flow cytometry (FCM) and cytomorphology results obtained on 227 cerebrospinal fluids investigated for hematologic malignancy, in a retrospective longitudinal study with a median observation time of 11 months. A combined method assessment (CMA), defining "positive" a sample if at least one method gave "positive" results, was also tested. Eleven out of 55 screening samples and 53 out of 166 follow-up samples resulted positive at clinical evaluation. FCM and CM were concordant with positive clinical assessment in 68.5% and 51.5% of cases, respectively. According to CMA, 10.5% of samples (resulting false negative by either FCM or cytomorphology) were rescued as true positive. FCM retained significantly higher accuracy than cytomorphology (p=0.0065) and 100% sensitivity when at least 220 leukocytes were acquired. CMA accuracy was higher than FCM accuracy and significantly higher than cytomorphology accuracy in the analysis of all samples (p<0.0001), samples from mature B/T cell neoplasms (p=0.0021), and samples drawn after intrathecal treatment (p=0.0001). When acquiring ≤220 leukocytes, FCM accuracy was poor, and combining cytomorphology added statistically significant diagnostic advantage (p=0.0043). Although FCM is the best diagnostic tool for evaluating CSF, morphology seems helpful especially when clinically positive follow-up samples are nearly acellular.  相似文献   
322.
We investigated whether juveniles of the nocturnal fish jundiá (Rhamdia quelen) and the diurnal fish Nile tilapia (Oreochromis niloticus) are able to chemically communicate stress to conspecifics. Groups of 8 fish were reared in tanks under recirculated water (water exchanged among all the tanks) for each species. Fish were handled in half of the tanks (stressor fish) and whole-body cortisol concentrations were compared among handled fish, non-handled fish exposed to water from the handled fish, and non-handled control fish held with no water communication. For each treatment cortisol concentrations were determined before exposure to the stressor (basal levels) and after 1, 2, 4, 8, and 24h. Basal levels of cortisol confirmed fish were unstressed in the beginning of the experiment. Cortisol was increased in the stressor fish 1h after handling. Fish receiving water from the stressor fish increased cortisol levels later (2h after the stressor fish were handled). As the isolated control group maintained cortisol levels unchanged throughout the experiment, we concluded that some chemical factor was released by the stressed fish in the water and thus stressed the conspecifics. This pattern was similar for both unrelated species, thus suggesting that this communication might have evolved earlier in fish and reinforcing the biological value of this kind of information.  相似文献   
323.
324.
BACKGROUND: The possible relationship between serum total cholesterol (TC) levels and outcome following ischemic stroke is still controversial. We evaluated the association between TC levels and 30-day mortality in a sample of older patients with acute ischemic stroke. METHODS: We enrolled 490 older patients with severe ischemic stroke consecutively admitted to University Hospital's Internal Medicine or Geriatrics Department. Stroke type was classified according to the Oxfordshire Community Stroke Project. The data recorded included clinical features, medical history, electrocardiogram, and blood analyses. Patients were divided into three groups by TC levels: group I (TC<4.1 mmol/L), group II (TC 4.1-5.2 mmol/L), and group III (TC>5.2 mmol/L). RESULTS: The overall mortality was 27.7%. Mortality was higher in patients with low TC levels (47.4%) compared with those with normal and high TC levels (23.0% and 24.1%, respectively). The odds ratio (OR) for short-term death was 2.17 (95% confidence interval [CI] 1.22-3.85) in group I compared with group III, after adjustment for age and gender. This result did not change after adjustment for possible confounders (OR 2.87; 95% CI 1.23-6.68). A similar trend was observed after adjustment for the Oxfordshire classification, age, and gender (OR 1.67; 95% CI 0.83-3.33). CONCLUSIONS: Short-term mortality following ischemic stroke is higher in older participants with low TC levels, independent of a large number of factors. Low TC levels might be useful in identifying frail older participants at high risk of stroke short-term mortality.  相似文献   
325.
BackgroundAnemia is common in congestive heart failure, and it has been associated with poor prognosis. The effect of anemia on functional ability in heart failure has not been described. We evaluated the relationship of anemia, physical disability, and survival in patients with heart failure.Methods and ResultsOne-year longitudinal study of 567 non-disabled, hospitalized heart failure patients, age ≥65 years, enrolled in the Italian Group of Pharmacoepidemiology in the Elderly Study. Anemia was defined according to the World Health Organization criteria. Physical disability was defined as dependence in performing at least 2 basic activities of daily living. After adjustment for disease severity and health-related variables, anemia was associated with higher risk of disability (odds ratio = 2.17; 95% confidence interval [CI] = 1.12–4.24). After stratification according to gender, a strong relationship of anemia and risk of disability persisted in women, but it was reduced in men. Anemic women were significantly more likely to die during the follow-up, even after adjustment for potential confounders (hazard ratio = 2.33; CI = 1.02–5.30).ConclusionAnemia is a predictor of physical disability in older heart failure patients, and in women anemia is associated with increased mortality.  相似文献   
326.
BACKGROUND: Uncertainty remains about the overall survival benefit of alcohol consumption and the mechanisms underlying the cardioprotective effect of light to moderate alcohol intake. Recent evidence suggests an anti-inflammatory effect of light to moderate alcohol consumption. We investigated the relationship of alcohol intake with all-cause mortality and cardiac events and evaluated whether this relationship is mediated or modified by inflammatory markers. METHODS: The analysis included 2487 subjects, aged 70 to 79 years, without baseline coronary heart disease (CHD) or heart failure (HF), participating in the Health, Aging, and Body Composition study. All-cause mortality and incident cardiac events (CHD and HF) were detected during a mean follow-up of 5.6 years. Alcohol consumption and serum levels of interleukin-6 (IL-6) and C-reactive protein (CRP) were assessed at baseline. RESULTS: A total of 397 participants died, and 383 experienced an incident cardiac event. Compared with never or occasional drinkers, subjects drinking 1 to 7 drinks per week had lower age-, sex-, and race-adjusted incidences of death (27.4 vs 20.1 per 1000 person-years, respectively) and cardiac events (28.9 vs 20.8 per 1000 person-years). After adjustment for confounders, compared with never or occasional drinkers, light to moderate drinkers (1-7 drinks per week) showed a decreased risk of death (hazard ratio [HR], 0.75; 95% confidence interval [CI], 0.56-1.00) and cardiac events (HR, 0.72; CI, 0.54-0.97). Adjustment for potential mediators, and particularly inflammatory marker levels, did not affect the strength of this association. CONCLUSION: Light to moderate alcohol consumption was associated with significantly lower rates of cardiac events and longer survival, independent of its anti-inflammatory effect.  相似文献   
327.
Bupivacaine is a long-acting local anaesthetic that is widely used in medicine and dentistry. The duration and intensity of its sensory blockade in animal models is increased by its inclusion in complexes with cyclodextrins. The aim of the present study was to evaluate the anaesthetic efficacy of bupivacaine 2-hydroxypropyl-β-cyclodextrin (HPβCD) inclusion complex for dental anaesthesia after inferior alveolar nerve block in rats. Thirty rats were each given an injection close to the mandibular foramen of 0.2 ml of one of the following formulations: 0.5% bupivacaine alone; 0.5% bupivacaine with 1:200,000 epinephrine; and 0.5% bupivacaine-HPβCD inclusion complex (bupivacaine-HPβCD). The other sides were used as controls, with either 0.9% saline or anaesthetic-free HPβCD solution being injected. The onset, success, and duration of pulpal anaesthesia were assessed by electrical stimulation (“pulp tester”) on inferior molars. Results were analysed using ANOVA (Tukey), log rank, and chi square tests (α = 5%). There were no differences among the formulations in onset of anaesthesia (p = 0.59) or between the bupivacaine plus epinephrine and bupivacaine plus HPβCD in duration of anaesthesia, but bupivacaine plus epinephrine gave significantly higher values than bupivacaine alone (p = 0.007). Bupivacaine plus epinephrine was a better anaesthetic than bupivacaine alone (p = 0.02), while Bupi-HPβCD gave intermediate results, and therefore did not differ significantly from the other 2 groups (p = 0.18 with bupivacaine alone; and p = 0.44 with bupivacaine plus epinephrine). The bupivacaine-HPβCD complex showed similar anaesthetic properties to those of bupivacaine with epinephrine.  相似文献   
328.
Prenatal diagnoses of the genetic disorders alpha, beta thalassemia, HbS, Hb Lepore, hemophilia and cystic fibrosis were sought in 88 cases. Six unsuccessful attempts at diagnosis resulted from DNA polymorphisms which were only 50% informative (four cases) and prenatal diagnoses which had been undertaken before it was known whether DNA polymorphisms in family studies were informative (two cases). The most frequent indications for prenatal diagnosis were the hemoglobinopathies although requests for exclusion of cystic fibrosis formed the majority during 1989. Strong linkage disequilibrium between the cystic fibrosis defect and its associated DNA polymorphisms facilitated detection of this disorder. Late presentations among patients with beta thalassemia and hemophilia and the necessity for more specialised genetic counselling were the commonest problems encountered.  相似文献   
329.
In 13 subjects affected by β-thalassaemia major, in three subjects affected by β-thalassaemia minor and in five normal healthy persons haemoglobin synthesis and the survival of red cells transfused into normal, group compatible, healthy recipients has been studied. The existence of an excess of newly synthesized α-chains and of a negative correlation between the excess α-chain and the red-cell survival has been demonstrated. The harmful role of the α-chain excess on the erythrocyte and the implications of this finding are discussed.  相似文献   
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