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101.
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The dendritic morphology of pyramidal cells located at the base of layer III in the primary visual area (V1), the second visual area (V2), the middle temporal area (MT), the ventral portion of the lateral intraparietal area (LIPv) and in the portion of cytoarchitectonic area 7a within the anterior bank of the superior temporal sulcus was revealed by injecting neurons with Lucifer Yellow in fixed, flattened slices of macaque monkey visual cortex. These areas correspond to different levels of the occipitoparietal cortical 'stream', which processes information related to motion and spatial relationships in the visual field. The tissue was immunocytochemically processed to obtain a light-stable diaminobenzidine reaction product, revealing the dendritic morphology in fine detail. Retrogradely labelled MT- projecting neurons in supragranular V1 (layer IIIc of Hassler's nomenclature, corresponding to Brodmann's layer IVb) were predominantly pyramidal, although many spiny multipolar (stellate) cells were also found. The average basal dendritic field area of pyramidal neurons in sublamina IIIc of V1 was significantly smaller than that in the homologous layer of V2, within the cytochrome oxidase-rich thick stripes. Furthermore, the average basal dendritic field areas of V1 and V2 pyramidal neurons were significantly smaller than those of neurons in MT, LIPv and area 7a. There was no difference in basal dendritic field area between layer III pyramidal neurons in areas MT, LIPv and 7a. While the shape of most basal dendritic fields was circularly symmetrical in the dimension tangential to the cortical layers, there were significant biases in complexity, with dendritic branches tending to cluster along particular axes. Sholl analysis revealed that the dendritic fields of neurons in areas MT, LIPv and 7a were significantly more complex (i.e. had a larger number of branches) than those of V1 or V2 neurons. Analysis of basal dendritic spine densities revealed regional variations along the dendrites, with peak densities being observed 40-130 microns from the cell body, depending on the visual area. The peak spine density of layer III pyramidal neurons in V1 was lower than that observed in V2, MT or LIPv, which were all similar. Pyramidal neurons in area 7a had the greatest peak spine density, which was on average 1.7 times that found in V1. Calculations based on the average spine density and number of dendritic branches at different distances from the cell body demonstrated a serial increase in the total number of basal dendritic spines per neuron at successive stations of the occipitoparietal pathway. Our observations, comparing dendritic fields of neurons in the homologous cortical layer at different levels of a physiologically defined 'stream', indicate changes in pyramidal cell morphology between functionally related areas. The relatively large, complex, spine-dense dendritic fields of layer III pyramidal cells in rostral areas of the occipitoparietal pathway allow these cells to sample a greater number of more diverse inputs in comparison with cells in 'lower' areas of the proposed hierarchy.   相似文献   
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BACKGROUND: In addition to human immunodeficiency virus, human T- lymphotropic virus types I and II (HTLV-I/II) is prevalent among blood donors in the United States. In Greece, there are no epidemiologic data regarding the prevalence of HTLV-I/II among volunteer blood donors and high-risk groups. STUDY DESIGN AND METHODS: To determine the prevalence of HTLV-I/II infections in northwestern Greece, a seroepidemiologic study was conducted among volunteer blood donors, multiply transfused patients, heroin addicts, and chronic hemodialysis patients. The subjects were tested for serologic evidence of HTLV-I/II infection by enzyme immunoassays and specific protein immunoblot confirmatory test. RESULTS: None of the volunteer blood donors and heroin addicts had detectable antibodies to HTLV-I/II. Only 1 (1.45%) of the 69 multiply transfused patients had indeterminate results, while 2 (1.2%) of 163 hemodialysis patients were positive. CONCLUSION: In northwestern Greece, routine screening for HTLV-I and HTLV-II infections does not appear to be required. However, the finding of seropositivity among hemodialysis patients requires further evaluation of the origin of the infection, as its zero prevalence in this population seems to exclude transfusion transmission.  相似文献   
104.
A boy with focal glomerulosclerosis as a result of nephrotic syndrome became unresponsive to corticosteroids and cyclophosphamide. He was given prolonged subcutaneous heparin with reduction in proteinuria, return of corticosteroid sensitivity, and no further deterioration (possibly improvement) in histological appearance. He remained completely well after five years.  相似文献   
105.
A study was undertaken to identify the nutritional parameters associated with a high risk of postoperative sepsis. The nutritional status of 162 cancer patients subjected to clean or clean-contaminated elective surgery was preoperatively evaluated according to the following parameters: percentage weight loss, arm circumference, triceps skinfold, arm muscle circumference, creatinine-height index, total serum protein, serum albumin, total iron-binding capacity, cholinesterase, peripheral lymphocytes, complement C3-C4 components, and skin tests. Patients were followed postoperatively according to a precise protocol to classify them as infected or noninfected. Postoperative sepsis was present in 40 patients who had significantly different mean values for four nutritional parameters from those of 114 patients with no complications, ie, total serum protein, 6.60 vs 6.99 g/dl, p = 0.008; serum albumin, 3.39 vs 3.66 g/dl, p = 0.001; total iron-binding capacity 301.32 vs 337.17 mmg/dl, p = 0.006; and cholinesterase, 2389.77 vs 2770.10 mU/ml, p = 0.005. Moreover, the relative risk and the attributable risk for these variables were evaluated and the significance was tested by the chi 2 test. By using multiple logistic analysis it appeared that only total serum protein and total iron-binding capacity gave an independent contribution to the risk of postoperative sepsis, while serum albumin disappeared and cholinesterase became non significant when the contribution of the first two variables was accounted for. It was also possible to identify, in a small number of patients, combinations of two variables that were associated with a very high risk of postoperative sepsis.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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Purpose

To provide updated information on trends and determinants of underweight, overweight, and obesity in Italian adults.

Methods

We considered data from 5 surveys conducted annually between 2006 and 2010, on a total of 14,135 subjects aged 18 years or more (6,834 men and 7,301 women), representative of the Italian adult population, including self-reported information on height and weight.

Results

Overall, 3.1 % of the Italian adult population was underweight (body mass index, BMI, <18.5 kg/m2; 0.8 % men, 5.3 % women), 31.8 % overweight (25≤ BMI <30 kg/m2; 39.8 % men, 24.4 % women), and 8.9 % obese (BMI ≥30 kg/m2; 8.5 % men, 9.4 % women). We observed no specific pattern of overweight/obesity across calendar years in men (multivariate prevalence ratios, PR, for 2010 vs 2006: 0.95; p for trend: 0.980) and a non-significant decreased trend in women (PR: 0.92; p for trend: 0.051). Prevalence of overweight/obesity significantly increased with age (PRs for ≥65 vs 18–24 years: 2.01 in men, 2.65 in women), decreased with education (PRs for high vs low education: 0.79 in men, 0.54 in women), and was less frequent in single than in married adults (PRs: 0.85 in men, 0.78 in women). Overweight/obesity was significantly more frequent in adults from southern versus northern Italy (PRs: 1.13 in men, 1.32 in women) and in former versus never smokers (PRs: 1.23 in men, 1.19 in women).

Conclusions

In Italy, we did not find unfavorable trends in overweight and obesity prevalence across calendar years. However, there are specific subgroups of the population with elevated prevalence of overweight and obesity, mainly adults from southern Italy and less educated ones.  相似文献   
109.
BACKGROUND: Heparins and warfarin are currently used as venous thromboembolism (VTE) prophylaxis in surgery. Inhibition of factor (F) Xa provides a specific mechanism of anticoagulation and the potential for an improved benefit-risk profile. OBJECTIVES: To evaluate the safety and efficacy of apixaban, a potent, direct, oral inhibitor of FXa, in patients following total knee replacement (TKR), and to investigate dose-response relationships. PATIENTS/METHODS: A total of 1238 patients were randomized to one of six double-blind apixaban doses [5, 10 or 20 mg day(-1) administered as a single (q.d.) or a twice-daily divided dose (b.i.d.)], enoxaparin (30 mg b.i.d.) or open-label warfarin (titrated to an International Normalized Ratio of 1.8-3.0). Treatment lasted 10-14 days, commencing 12-24 h after surgery with apixaban or enoxaparin, and on the evening of surgery with warfarin. The primary efficacy outcome was a composite of VTE (mandatory venography) and all-cause mortality during treatment. The primary safety outcome was major bleeding. RESULTS: A total of 1217 patients were eligible for safety and 856 patients for efficacy analysis. All apixaban groups had lower primary efficacy event rates than either comparator. The primary outcome rate decreased with increasing apixaban dose (P = 0.09 with q.d./b.i.d. regimens combined, P = 0.19 for q.d. and P = 0.13 for b.i.d. dosing).A significant dose-related increase in the incidence of total adjudicated bleeding events was noted in the q.d. (P = 0.01) and b.i.d. (P = 0.02) apixaban groups; there was no difference between q.d. and b.i.d. regimens. CONCLUSIONS: Apixaban in doses of 2.5 mg b.i.d. or 5 mg q.d. has a promising benefit-risk profile compared with the current standards of care following TKR.  相似文献   
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