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A Friend is truly a treasure, in accordance with age and competence’s qualitative changes. The aim of this study was to con?rm the increase in friendship competence and its multifactorial nature in 3- up to 10-year-old children, and to verify gender differences, and parenting in?uences on the concept of friendship. A semi-structured interview was administered in a natural context to 3- to 10-year-old children (N?=?167; Mean?=?7.6 years; SD?=?2.16). According to Selman’s Model, the coding provides ?ve sub-categories: (1) friendship; (2) social perspective taking; (3) emotions understanding; (4) social interaction strategies; and (5) aggressiveness. Three parental style questionnaires were administered to parents. Results point up an increase in social skills according to age. The Friendship Interview turned out to be a reliable tool able to investigate how the concept of friendship is also structured in preschool children.  相似文献   
3.
The implantation of chondrocytes, seeded on matrices such as hyaluronic acid or collagen membranes, is a method that is being widely used for the treatment of chondral defects. The aim of the present study was to evaluate the distribution, viability and phenotype expression of the cells seeded on a collagen membrane just at the time of the implantation. Twelve patients who were suffering from articular cartilage lesions were treated by the MACI® procedure. The residual part of each membrane was tested by colorimetric assay (MTT) and histochemical and ultrastructural analyses were carried out. In all of the samples a large number of viable cells, quite homogenously distributed, was detected. The cells expressed the markers of the differentiated hyaline chondrocytes. These data reassure in that the MACI procedure provides a suitable engineered tissue for cartilage repair, in line with the clinical evidences emerging in the literature.  相似文献   
4.
Aims In an attempt to reverse multidrug resistance, in a recent trial of verapamil in association with doxorubicin, we used escalating doses of continuous intravenous (i.v.) verapamil under close haemodynamic monitoring. We report the pharmacokinetics of escalating doses of verapamil. Methods We studied nine patients [ seven males, two females; median age 46 years (range, 31–57)] with advanced adenocarcinoma of the colon and normal renal, hepatic, and cardiac functions. After a loading dose (0.15 mg kg−1 followed by 12 h continuous i.v. infusion at 0.20 mg kg−1 h−1 ), the infusion rate (ko) of verapamil was increased every 24 h (0.25, 0.30, 0.35, and 0.40 mg kg−1 h−1 ). The highest rate was maintained for 48 h. Doxorubicin was given as a continuous i.v. infusion from 12 to 108 h (n=4) or 60 to 108 h (n=5). Blood samples and urine collections were taken every 12 h. Verapamil and nor-verapamil were assayed by high performance liquid chromatography. We calculated systemic clearance of verapamil (CL=ko/Css ) and renal clearance (CLr) of verapamil and nor-verapamil. The Cssvs rate relationship was fitted to a Michaelis-Menten equation: Css=ko(Km+Css )/(V Vm ). Results CL was dose-dependent and in all nine patients a significant reduction in CL was observed over the dose range (mean CL±s.d. were 0.51±0.31, 0.38±0.16, 0.32±0.18, and 0.27±0.11 l h−1 kg−1, respectively, at 0.25, 0.30, 0.35, and 0.40 mg kg−1 h−1; P=0.0001). Css increased more than proportionally to the dose rate and the Cssvs rate relationship was best defined by a Michaelis-Menten equation (Km=730 μg l−1; V Vm=0.55 mg kg−1 h−1 ), (r=0.994; P=0.006). CLr of verapamil and nor-verapamil was not saturable but the contribution to the elimination was only 2 to 4% of the dose. Conclusions These findings suggest a non-linear, capacity-limited metabolic clearance of high-dose verapamil. Using escalating infusion rates, high verapamil concentrations (1500–2500 ng ml−1 ) were achieved without major toxicity. Saturable clearance may cause higher bioavailability and slower elimination of verapamil after acute oral overdoses.  相似文献   
5.
The prevalence of abnormal physical signs (e.g., bleeding, scars, or bruises) and genital infections, notably Chlamydia Trachomatis, Neisseria Gonorrhea, and Herpes Simplex Genitalis was studied in 219 female children with validated sexual abuse. They were compared to 113 nonabused female children. The average abused child was 8.3 years old, with 69% having been abused on multiple occasions. Most offenders were family members (65%) or a close family friend (22%). Stranger-perpetrated sexual assault, in the sample, was low (9.1%). Few children had severe vaginal tears, though 56% showed signs of subtle anatomical injury to their genitalia. No similar anatomical abnormalities were present in nonabused children. Among the sexually abused children and adolescents, 35% were colonized with a pathogen or a potential pathogen, compared to a prevalence rate of 18.5% in non-abused children. The proportion of abused children colonized with Ureaplasma Urealyticum and Mycoplasma Hominis was not significantly different from that found in nonabused children. At present, Neisseria gonorrhea and Chlamydia Trachomatis remain the only conclusive markers for sexual abuse. It is recommended that routine cultures of the pharyngeal, rectal, and vaginal areas be taken in all cases of suspected child sexual abuse, regardless of clinical findings.  相似文献   
6.
PDB is genetically heterogeneous. Mutations of the sequestosome1 gene have been reported in sporadic and familial forms of Paget's in patients of French Canadian and British descent. Mutational analyses in different ethnic groups are needed to accurately investigate hereditary diseases. We describe two novel mutations of sequestosome1 in 62 Italian sporadic patients, confirming the role of the encoded protein in this disorder. INTRODUCTION: Paget's disease of bone (PDB) is a relatively common disease of bone metabolism reported to affect up to 3% of whites over 55 years of age. The disorder is genetically heterogeneous, and at present, there is scientific evidence that at least eight different human chromosomal loci are correlated with its pathogenesis. Mutations of the sequestosome1 (SQSTM1) gene were identified as responsible for most of the sporadic and familial forms of Paget in patients of French Canadian and British descent. Such mutations were located at exon 7 and 8 levels, encoding for the ubiquitin protein-binding domain (UBA) and representing a mutational hot spot area. MATERIALS AND METHODS: To verify the involvement of this gene in Italian subjects affected by PDB, we performed mutational analysis in 62 sporadic PDB cases. RESULTS: We described three different mutations at exon 8 level: P392L, already described in the French Canadian population and families predominantly of British descendent, and two novel mutations consisting of the amino acid substitutions M404V and G425R. No significant differences in the clinical history of PDB have been observed in patients with SQSTM1 mutations in respect to those without. CONCLUSIONS: Even though our findings suggest a minor involvement of the SQSTM1 gene in the pathogenesis of sporadic Italian Paget's cases, the identification of different significant mutations within the SQSTM1 gene in unrelated, but clinically similar individuals, offers extremely convincing evidence for a causal relationship between this gene and PDB. Longitudinal studies are needed to assess the penetrance of genotype/phenotype correlations. Our findings confirm the evidence of a clustered mutation area at this level in this disorder.  相似文献   
7.
Abstract From our overall experience in 56 patients, we here report the treatment with matrix-induced autologous chondrocyte implantation (MACI) of 35 patients suffering from knee cartilage defects measuring about 4 cm2, and followed for a minimum of 6 months. A total of 36 knees were treated (1 patient on both knees) and clinically observed for 22 months (in some cases for over 39 months), in accordance with a standardised protocol. Subjective parameters (pain, well-being, functional state, symptoms during specific activity) and objective outcomes (IKDC score and Lysholm and Tegner scores) were recorded. One or 2 years after implantation, some biopsies of the regenerated cartilage were histologically evaluated. The subjective parameters (VAS pain score, 2.80±1.49, p<0.0001; change vs. basal score, 2.72) promptly normalized after 1 month, as did the objective ones (IKDC score after 6 months, 1.53±0.59, p<0.0001; change vs. basal score, 1.78). Similar results were observed after the treatment of a femoropatellar kissing lesion. The three cartilage biopsies that were analysed from different patients showed a tissue positivity to immunohistochemical markers of hyaline cartilage. The conclusions of this preliminary analysis are that the clinical outcome and histological evaluation suggest that MACI is able to relieve pain and restore the functionality of the knee, and that the treatment appears capable of regenerating hyaline cartilage.  相似文献   
8.
We studied the relationship between Osgood-Schlatter disease and torsional abnormalities of the lower limb in 21 boys with this condition and 20 age- and sex-matched controls. 3 groups of knees (20 control knees, 21 symptomatic and 21 asymptomatic or less symptomatic knees) were subjected to clinical, radiographic and CT evaluation. We found no statistically significant differences between patients and controls, as regards femoral anteversion, patellar congruence angle, patellar tilt angle and anterior tibial tuberosity-trochlear groove distance, but the condylomalleolar angle and tibial torsion angle were greater in patients. We found no differences between symptomatic and asymptomatic or less symptomatic knees in any of the parameters. All the symptomatic knees were on the side preferentially involved in jumping and sprinting. This increase in external tibial torsion may play a role as a predisposing mechanical factor in the onset of Osgood-Schlatter disease in male athletes.  相似文献   
9.
The effect of carrier priming on antibody avidity was investigated under several experimental conditions. Basically, mice were carrier primed with HRBC (horse red blood cells) prior to immunization with TNP (2,4,6-trinitrophenyl) conjugated to HRBC. Immunization was performed either in vivo or in spleen cell culture, and avidity of anti-TNP antibodies was estimated from inhibition of direct PFC (plaque-forming cells) by free TNP-BSA (-bovine serum albumin).The data indicate the appropriate conditions under which carrier priming can enhance antibody avidity. The carrier effect is maximized by priming the animals with 104-105 HRBC 3-7 days before immunization with a low dose of TNP-HRBC. Hyper-immunization by repeated injections of a high dose of the conjugate does not modify the carrier effect on avidity but it delays the fall of avidity in both carrier primed and unprimed animals. These results are interpreted in terms of T- and B-cell co-operation within the framework of the maturation theory of antibody affinity.Carrier priming was also found to increase the number of direct PFC of the IgM and, mostly, of the non-IgM classes, a finding in agreement with the notion that T cells can help IgM production and the shift to IgG.  相似文献   
10.
Vitiligo is a skin disorder characterized by depigmented macules secondary to melanocyte loss. An unusual facet is its relation to melanoma: cytotoxic T lymphocytes directed to melanocyte antigens are found in both conditions and imply a breakdown of tolerance, yet the resulting immune reaction is the opposite. The mechanisms at the basis of these opposite effects are not known. Here, we performed a direct comparison of whole melanocyte-specific T cell populations in the two diseases. We demonstrate that neither precursor frequencies of Melan-A/MART-1-specific T lymphocytes nor their status of activation differ significantly. However, by using a tetramer-based T cell receptor down-regulation assay, we documented a higher affinity of vitiligo T cells. We calculated that the peptide concentration required for 50% of maximal receptor down-regulation differed by 6.5-fold between the two diseases. Moreover, only vitiligo T cells were capable of efficient receptor down-regulation and IFN-gamma production in response to HLA-matched melanoma cells, suggesting that this difference in receptor affinity is physiologically relevant. The differences in receptor affinity and tumor reactivity were confirmed by analyzing Melan-A/MART-1-specific clones established from the two diseases. Our results suggest that the quality, and not the quantity, of the melanocyte-specific cytotoxic responses differs between the two pathologies.  相似文献   
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