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31.
Marangoni F Agostoni C Lammardo AM Giovannini M Galli C Riva E 《The British journal of nutrition》2000,84(1):103-109
While a wealth of data on the fatty acid composition of mature human milk has been published, limited information is available on the quantities of individual fatty acids supplied to the suckling infant with maternal milk, through the whole first year of life. Our aim was to qualitatively and quantitatively evaluate the fatty acid composition of human milk from Italian mothers, throughout extended lactation with particular emphasis on the long-chain polyunsaturated fatty acids. We have thus measured the total fat content and the concentrations of major fatty acids by quantitative GLC in pooled breast hindmilk collected from all feedings over 24 h at colostrum, 1, 3, 6, 9 and 12 months in ten mothers recruited after delivery of full-term infants. Total saturated fatty acids progressively increase and total monounsaturated progressively decrease as percentage levels, while among long-chain polyunsaturated fatty acids, percentages of arachidonic acid and docosahexaenoic acid decrease from colostrum up to the third month. Hindmilk total lipids (mg/dl) rise more than twofold up to 3 months, and then remain stable. The amounts (mg/dl) of linoleic acid and alpha-linolenic acid progressively increase, following the trend of total fat, while arachidonic and docosahexaenoic concentrations (mg/dl) remain stable throughout the whole nursing period. Assessment of the intakes per kg body weight shows different trends for the individual major long-chain polyunsaturated fatty acids supplied to the infant from hindmilk during exclusive breast-feeding (3 months). This information may be useful for the evaluation of infant intakes during extended lactation. 相似文献
32.
Calcium-dependent modulation of FGF-2 expression in cultured cerebellar granule neurons 总被引:1,自引:0,他引:1
We investigated the expression for fibroblast growth factor-2 (FGF-2), in cultured rat cerebellar granule cells and its modulation by Ca2+ regulating agents. There were no significant differences in the levels of FGF-2 mRNA in cells cultured in high vs low K+. The expression of the trophic factor is induced by Ca2+ entry through the plasma membrane only in mature neurons but not at an early stage of maturation. Conversely the release of Ca2+ from intracellular stores increased the expression for FGF-2 at 2 or 7 days in culture. suggesting that is not dependent upon cellular maturation. These results suggest that specialized mechanisms can operate to regulate FGF-2 expression and that the integration of electrical and receptor-mediated signals for its modulation within cerebellar granule neurons may depend upon the maturational stage of the cells. 相似文献
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34.
Effect of panretinal photocoagulation on retinal blood flow in proliferative diabetic retinopathy 总被引:5,自引:0,他引:5
The effect of panretinal photocoagulation (PRP) on retinal volumetric blood flow rate and its regulatory response to hyperoxia was investigated in a main temporal vein of 15 eyes with proliferative diabetic retinopathy, using bi-directional laser Doppler velocimetry and monochromatic fundus photography. At an average of 4 +/- 2 months after the beginning of PRP, retinal venous diameter decreased from an average of 174 +/- 20 micron to 162 +/- 19 micron (P less than 0.01), red blood cell velocity decreased from 1.3 +/- 0.4 cm/sec to 1.1 +/- 0.4 cm/sec (P less than 0.01), and blood flow decreased from 11.5 +/- 3.8 microliter/min to 8.4 +/- 3.3 microliter/min (P less than 0.001). The regulatory response to hyperoxia, characterized by the percentage decrease in retinal blood flow during 100% oxygen breathing, improved from 20 +/- 15% prior to treatment to 45 +/- 12% following treatment (P less than 0.001). The decrease in retinal blood flow is most likely due to a decrease in viable retinal tissue and an improvement in retinal oxygenation following PRP. The increase in the regulatory response to 100% O2 breathing following PRP may also result from such an improved retinal oxygenation. 相似文献
35.
Piffaretti G Tozzi M Lomazzi C Rivolta N Riva F Caronno R Castelli P 《American journal of surgery》2007,193(2):166-170
BACKGROUND: This study assessed the endovascular embolization of splenic artery aneurysms and false aneurysms with special consideration given to postoperative complications. METHODS: Fifteen patients (11 women; mean age, 56 y; range, 39-80 y) with splenic artery aneurysm (n = 13) or false aneurysm (n = 2) were treated with coil embolization. The lesion was asymptomatic in 9 patients, symptomatic in 5 patients, and ruptured in 1 patient. The mean aneurysm diameter was 33 +/- 23 mm (range, 15-80 mm). Postoperative follow-up evaluation included a clinical visit and spiral computed tomography at 1, 4, and 12 months, and yearly thereafter. RESULTS: Endovascular treatment was possible in 14 patients (93%) (1 failure: neck cannulation). Perioperative mortality was not observed. Morbidity included postembolization syndrome in 5 patients (30%). Neither pancreatitis nor spleen abscess occurred. The mean follow-up period was 36 months (range, 3-60 mo). During follow-up evaluation we detected 1 sac reperfusion that was sealed successfully with additional coils. Surgical conversion or open repair were never required. CONCLUSIONS: At our institute, endovascular treatment represents the first-line treatment for splenic artery aneurysms. Postembolization syndrome and infarcts are common events but generally resolve without sequelae. 相似文献
36.
Filippo Monelli Francesco Venturelli Lisa Bonilauri Elisa Manicardi Valeria Manicardi Paolo Giorgi Rossi Marco Massari Guido Ligabue Nicoletta Riva Susanna Schianchi Efrem Bonelli Pierpaolo Pattacini Maria Chiara Bassi Giulia Besutti 《肝癌研究(英文版)》2021,7(4):13-24
Aim: In this systematic review, guidelines on non-alcoholic fatty liver disease (NAFLD) were evaluated, aiming at a guideline synthesis focusing on diagnosis an... 相似文献
37.
38.
Falls have major consequences both at societal (health-care and economy) and individual (physical and psychological) levels. Questionnaires to assess fall risk are commonly used in the clinic, but their predictive value is limited. Objective methods, suitable for clinical application, are hence needed to obtain a quantitative assessment of individual fall risk. Falls in older adults often occur during walking and trunk position is known to play a critical role in balance control. Therefore, analysis of trunk kinematics during gait could present a viable approach to the development of such methods. In this study, nonlinear measures such as harmonic ratio (HR), index of harmonicity (IH), multiscale entropy (MSE) and recurrence quantification analysis (RQA) of trunk accelerations were calculated. These measures are not dependent on step detection, a potentially critical source of error. The aim of the present study was to investigate the association between the aforementioned measures and fall history in a large sample of subjects (42 fallers and 89 non-fallers) aged 50 or older. Univariate associations with fall history were found for MSE and RQA parameters in the AP direction; the best classification results were obtained for MSE with scale factor τ = 2 and for maximum length of diagonals in RQA (72.5% and 71% correct classifications, respectively). MSE and RQA were found to be positively associated with fall history and could hence represent useful tools in the identification of subjects for fall prevention programs. 相似文献
39.
In 13 patients with congestive heart failure we tested the acute hemodynamic effects of 5 vs. 10 mg felodipine tablets, in a double-blind, cross-over study. One hour after felodipine 5 mg, echocardiographic ejection fraction (%), cardiac index (thermodilution-ml/min/m2), and pulmonary wedge pressure (mm Hg) significantly changed (from 21 +/- 2 to 26 +/- 2, 2350 +/- 150 to 2790 +/- 160, 24 +/- 4 to 17 +/- 4) while they remained steady after felodipine 10 mg. The greatest stroke index increases were associated with felodipine 5 mg in 12 patients and 10 mg in 1 patient. Therefore we evaluated (open study) the long-term (2 months- 1 year) clinical and hemodynamic efficacy following the treatment with the acutely most effective dose (twice daily). After 2 months ejection fraction, cardiac index and pulmonary wedge pressure were respectively 24 +/- 2, 2550 +/- 150, and 18 +/- 4 (12 hours after the last drug administration, n = 11, P less than 0.02 from baseline). These parameters further increased one to two hours after the following administration of felodipine. Clinical improvement (reduction of 1 functional class, according to the New York Heart Association) was observed in 8/13 patients. These 8 patients participated to the one year follow-up. In 5 patients follow-up was interrupted because of acute cardiovascular events. However, before study interruption (5 patients) or ending (3 patients) clinical status did not worsen and ejection fraction remained higher than in the pretreatment period. Therefore, low dose felodipine might be used in the treatment of congestive heart failure. 相似文献
40.
Riva A Loffredo F Uccheddu A Riva FT Tandler B 《The Journal of clinical endocrinology and metabolism》2003,88(4):1903-1906
By taking advantage of a modified osmium maceration technique, we have been able to examine by high resolution scanning electron microscopy (HRSEM) the interior of human adrenocortical mitochondria from which all soluble material has been extracted. The so-called vesicles apparent in thin sections examined by transmission electron microscopy actually are finger-like cristae as determined by HRSEM. These digitiform cristae have a segmented appearance and a bulbous tip. The segmented form of the cristae may have important metabolic implications. 相似文献