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51.
52.
Sale A Putignano E Cancedda L Landi S Cirulli F Berardi N Maffei L 《Neuropharmacology》2004,47(5):649-660
Rearing mice from birth in an enriched environment leads to a conspicuous acceleration of visual system development appreciable at behavioral, electrophysiological and molecular level. Little is known about the possible mechanisms of action through which enriched environment affects visual system development. It has been suggested that differences in maternal behavior between enriched and non-enriched conditions could contribute to the earliest effects of enriched environment on visual development and that neurotrophins, BDNF in particular, might be involved. Here, we examined Brain Derived Neurotrophic Factor (BDNF) levels in the visual cortex during development and showed that an increase occurs in the first week of life in enriched pups compared to standard reared pups; BDNF levels at birth were equal in the two groups. This suggests a postnatal rather than a prenatal effect of environment on BDNF. A detailed analysis of maternal care behavior showed that pups raised in a condition of social and physical enrichment experienced higher levels of licking behavior and physical contact compared to standard reared pups and that enhanced levels of licking were also provided to pups in an enriched environment where no adult females other than the mother were present. Thus, different levels of maternal care in different environmental conditions could act as indirect mediator for the earliest effects of enrichment on visual system development. Some of the effects of different levels of maternal care on the offspring behavior are long lasting. We measured the visual acuity of differentially reared mice at the end of the period of visual acuity development (postnatal day 45) and at 12 months of age, using a behavioral discrimination task. We found better learning abilities and higher visual acuity in enriched compared to standard reared mice at both ages. 相似文献
53.
Zanconato S Scollo M Zaramella C Landi L Zacchello F Baraldi E 《The Journal of allergy and clinical immunology》2002,109(3):440-445
BACKGROUND: Fractional exhaled nitric oxide (FE(NO)) and exhaled carbon monoxide (ECO) have been proposed as markers of airway inflammation and oxidative stress. OBJECTIVE: The aim of this study was to assess the effect of oral prednisone treatment on FE(NO) and ECO levels in a group of 30 asthmatic children with asthma exacerbation. METHODS: Thirty asthmatic children with asthma exacerbation were treated with oral prednisone for 5 days (1 mg/kg/day). Before and after prednisone therapy, ECO was measured by means of a chemical analyzer and FE(NO) was measured by means of a chemiluminescence analyzer. ECO and FE(NO) were also measured in a group of healthy nonatopic children. RESULTS: Before therapy, both ECO values and FE(NO) values were higher in asthmatic children (ECO, 3.2 +/- 0.2 ppm; FE(NO) online, 74.9 +/- 6.2 ppb; FE(NO) offline, 20.2 +/- 1.4 ppb) than in healthy controls (ECO, 2.0 +/- 0.2 ppm [P <.01]; FE(NO) online, 10.1 +/- 0.8 [P <.0001]; FE(NO) offline, 5.9 +/- 0.4 ppb [P <.0001]). An overlap in ECO values was found between healthy controls and asthmatic children. After prednisone therapy, there was a significant reduction in FE(NO) values (FE(NO) online, 40.6 +/- 4.6 ppb [P <.0001]; FE(NO) offline, 11.1 +/- 0.8 ppb [P < 0.0001]) and a slight but nonsignificant decrease in ECO values (2.7 +/- 0.2 ppm [P = not significant]) in the asthmatic group. No significant correlation between ECO values and FE(NO) values was found in either the asthmatic children or the controls. CONCLUSIONS: After a course of prednisone therapy, in children with asthma exacerbation there is a significant decrease in FE(NO) but no significant change in ECO levels. This possibly suggests that ECO is less sensitive than FE(NO) to inhibition by corticosteroids. 相似文献
54.
Landi A Cavazza S Caserta G Leti Acciaro A Sartini S Gagliano MC Manca M 《Hand Clinics》2003,19(4):631-48, vii
The authors report a simple chart that offers a comprehensive picture of spasticity of the upper limb and provides a more objective method of recording data. Distinction is made between fixed postures and the residual active range of motion at the shoulder and elbow. The presence and function of the muscles can be identified easily on dynamic EMG studies, which are essential for understanding the degree of spasticity and dyssynergy related to a single muscle. When spasticity of the upper arm is managed with a global approach and objectives are defined clearly in advance with the patient and caregivers, treatment of shoulder and elbow deformities can achieve important results for personal hygiene or functional targets. 相似文献
55.
How features of an object are bound into a unique percept is one of the puzzling problems in the cognitive and neuro-sciences. In order to investigate the spatio-temporal mechanisms of feature binding, we serially present two verniers with opposite offset directions for very short durations. Only one vernier is perceived with its offset dominated by the vernier presented second. This dominance reverses if the two verniers are followed by masking gratings, i.e. the first presented vernier dominates performance. Therefore, feature fusion can neither be explained completely by spatially local mechanisms nor by the temporal order of appearance of elements. 相似文献
56.
57.
Aim of this paper is to describe the methodology adopted to build up an epidemiological surveillance system on the reproductive health of women employed by the Regional Health System (Hospital Division). The implementation of this system required the set up of a relational database, with personal and health data collected from the 1st January 1998 to the 31st December 1998. The goals of research were: to describe the phenomenon of unfavorable reproductive events such as: death at birth, low weight at birth, birth defects, spontaneous abortions, voluntary abortions (for reasons linked to the child's and the pregnant woman's health), premature births and post term births; to provide the basis for further analytical studies on working activities with exposures of particular interest (antiblastic drugs, ionizing radiations and ergonomic factors); to contribute to evaluate the state of enforcement of the specific legislation. We computed raw, age-specific and standardized rates of the studied population as far as natality, spontaneous and voluntary abortivity and birth defects are concerned. The results showed an increased number of spontaneous abortions. Investigations are still in progress and an estimate of risks associated with chemical and physical exposures in this sector will be determined. 相似文献
58.
59.
Landi F Onder G Russo A Tabaccanti S Rollo R Federici S Tua E Cesari M Bernabei R 《Journal of clinical epidemiology》2001,54(9):968-970
The objective of the present study was to examine the effect of a home care program based on comprehensive geriatric assessment-Minimum Data Set for Home Care-and case management on hospital use/cost of frail elderly individuals. We determined all hospital admissions and days spent in hospital during the first year since the implementation of the home care program, and compared them to the rate of hospitalization that the same patients had experienced in the year preceding the implementation of such program. Following the implementation of this program, there was a significant reduction of the number of hospitalizations (pre 44% vs. post 26%, P < 0.001), associated with a reduction of hospital days, both at the individual patient level and for each admission. In conclusion, an integrated home care program based on the implementation of a comprehensive geriatric assessment instrument guided by a case manager has a significant impact on hospitalization and is cost-effective. 相似文献
60.
The effect of quinagolide and cabergoline, two selective dopamine receptor type 2 agonists, in the treatment of prolactinomas 总被引:6,自引:0,他引:6
Di Sarno A Landi ML Marzullo P Di Somma C Pivonello R Cerbone G Lombardi G Colao A 《Clinical endocrinology》2000,53(1):53-60
OBJECTIVE: To compare effectiveness and tolerability of quinagolide (CV 205-502) and cabergoline (CAB) treatments in 39 patients with prolactinoma. STUDY DESIGN: All 39 patients were treated first with quinagolide for 12 months and then with cabergoline for 12 months. A wash-out period was performed in all patients after 12 months of both treatments in order to evaluate recurrence of hyperprolactinaemia. PATIENTS: Twenty-three patients with microprolactinoma (basal serum PRL levels 1620-18750 mU/l) and 16 patients with macroprolactinoma (basal serum PRL levels 4110-111000 mU/l), previously shown to be intolerant of bromocriptine. All patients had gonadal failure and 11 patients with macroprolactinoma had visual field defects. Five patients with macro- and one with microprolactinoma had previously undergone surgery. STUDY PROTOCOL: The starting doses of quinagolide and CAB were 0.075 mg/day and 0.5 mg/week, respectively, subsequently increased up to 0.6 mg once daily and 1.5 mg twice weekly, respectively. Serum PRL levels were measured monthly for the first 3 months and then quarterly for 12 months. PRL levels were assayed weekly for the first month and then monthly during the wash-out period. Tumour shrinkage was evaluated by serial magnetic resonance imaging (MRI) studies of the hypothalamus-pituitary region at study entry and after 6 and 12 months of both treatments in micro- and macroprolactinomas. RESULTS: After 12 months of quinagolide treatment, serum PRL levels normalized in all 23 patients with microprolactinoma (100%) and in 14 out of 16 with macroprolactinoma (87.5%). A tumour volume reduction of greater than 80% was documented by MRI studies in five of 23 (21.7%) patients with microprolactinoma and in four of 16 (25%) with macroprolactinoma. All patients had recurrence of hyperprolactinaemia after 15-60 days withdrawal of quinagolide treatment. However, before starting CAB treatment basal PRL levels were significantly lower than before quinagolide treatment both in microprolactinomas (4667.4 +/- 714.7 vs. 2636.1 +/- 262.3 mU/l, P = 0.006) and in macroprolactinomas (24853.1 +/- 7566.7 vs. 3576.6 +/- 413.0 mU/l, P = 0.013). After 12 months of CAB treatment, serum PRL levels normalized in 22 out of 23 patients with microprolactinoma (95.6%) and in 14 out of 16 with macroprolactinoma (87.5%). No difference in PRL nadir was found after quinagolide and CAB treatments both in micro 174.6 +/- 30.6 vs. 169.8 +/- 37.9 mU/l, P = 0.5) and in macroprolactinomas (277.5 +/- 68.4 vs. 341.8 +/- 95.2 mU/l, P = 0.6). A tumour volume reduction of greater than 80% was documented by MRI studies in seven other patients with microprolactinoma (30.4%) and in five other patients with macroprolactinoma (31.2%). After CAB treatment, further tumour shrinkage ranging 4-40% and 2-70% was observed in 12 micro- and seven macroprolactinomas, respectively. The percentage of tumour shrinkage after CAB was significantly higher than that observed after quinagolide in microprolactinomas (48.6 +/- 9.5 vs. 26.7 +/- 4. 5%, P = 0.046) but not in macroprolactinomas (47.0 +/- 10.6 vs. 26.8 +/- 8.4%, P = 0.2). The withdrawal from CAB treatment, induced an increase in serum PRL levels in all macroprolactinomas between 15 and 30 days, in 15 out of 23 microprolactinoma after 30 days, and in four patients after 2-4 months. In the remaining four patients serum PRL levels remained normal after 12 months of CAB withdrawal. Both compounds were tolerated satisfactorily by all patients. In the first week of quinagolide treatment, 12 patients reported nausea and postural hypotension, which spontaneously disappeared during the second-third week of treatment. None of the 39 patients reported side-effects during CAB treatment. CONCLUSIONS: Both quinagolide and CAB treatments, induced the normalization of serum PRL levels in the great majority of patients with prolactinoma. Tumour shrinkage was recorded in 22-25% of patients after quinagolide and in 30-31% after CAB treatment 相似文献