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121.
BACKGROUND: We recently showed that two doses of 4 mg of zoledronic acid (ZOL) ameliorated the bone loss and improved bone histology within the first six months after kidney transplantation. The aim of the present study was to evaluate whether this early short-term intervention exhibited a sustained bone-sparing effect. METHODS: A homogenous group of 20 de novo renal transplant recipients were equally randomized to two infusions of 4 mg of ZOL or placebo at two weeks and three months after engraftment. Patients were followed up for three years by sequential determination of bone densitometry and specific biochemical markers. RESULTS: From month six to three years after transplantation, both treatment groups exhibited an improvement of bone mineralization. Femoral neck bone mineral density z-scores increased statistically significantly from -1.3 (2.6) to -0.2 (3.6) in the placebo group and from -1.6 (2.9) to -1.2 (1.9) in the ZOL group (median, range). Biochemical parameters of osteoblast activity such as osteocalcin and bone-specific alkaline phosphatase did not increase significantly in both groups. Osteoprotegerin, a marker of osteoclast inhibition, was significantly elevated over the first six months in the ZOL group, but decreased to similar levels, as in the placebo group, over the next two and a half years. Other markers of osteoclast activity such as c-telopeptide of type 1 collagen, calcitonin, and intact parathyroid hormone were not different between six months and three years in either group. CONCLUSION: The early bone-sparing effect of short-term ZOL therapy confers no sustained benefit versus placebo at three year post-transplantation.  相似文献   
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A random retrospective chart review was conducted to document serum carnitine levels on 100 children with autism. Concurrently drawn serum pyruvate, lactate, ammonia, and alanine levels were also available in many of these children. Values of free and total carnitine (p < 0.001), and pyruvate (p=0.006) were significantly reduced while ammonia and alanine levels were considerably elevated (p < 0.001) in our autistic subjects. The relative carnitine deficiency in these patients, accompanied by slight elevations in lactate and significant elevations in alanine and ammonia levels, is suggestive of mild mitochondrial dysfunction. It is hypothesized that a mitochondrial defect may be the origin of the carnitine deficiency in these autistic children.  相似文献   
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Background To determine whether iodide protects from UVB irradiation-induced destruction of hyaluronate and against UVB injury of cultured human conjunctival fibroblasts.Methods Hyaluronate and primary cultured human conjunctival fibroblasts were incubated with various concentrations of iodide and then exposed to UV light irradiation of 312 nm. Hyaluronate destruction was determined by viscosity measurements. Cell viability was assessed with MTT assay.Results Iodide protects hyaluronate from UVB light-induced degradation of this macromolecule in a concentration-dependent manner. Incubation of human conjunctival fibroblasts with iodide inhibited cells from damage by UVB light.Conclusion Iodide protects hyaluronate, a component of tear fluid and tissues of the anterior part of the eye, against UVB light-induced degradation. Also, injury of human conjunctival cells can be prevented by incubation with iodide before UVB irradiation. The mechanism of protection is likely to include an antioxidative reaction. To support the natural defence mechanisms of the eyes, the administration of an antioxidant such as iodide to artificial tears, for example, may help to prevent the damage of the eye provoked by oxidative stress.  相似文献   
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BACKGROUND: Alcohol is the most frequently used substance among adolescents with different patterns of consumption. Various types of adolescent alcohol use have been proposed, but only a few studies have looked for external validation of these types. METHOD: Data from 794 adolescents participating in the Zurich Adolescent Psychology and Psychopathology Study (ZAPPS) were used to evaluate the discriminant validity of the classification of four types of adolescent drinkers: abstainers, social drinkers, heavy drinkers, and problem drinkers. Data were based on questionnaires dealing with substance abuse, emotional and behavioral problems, life events, coping capacity, self-related cognitions, perceived parental behavior, perceived school environment, and the social network. RESULTS: There was a clear differentiation of the problem drinkers' group on almost all dimensions of the emotional and behavioral problems questionnaires, with the heavy drinkers' profile situated in between on some dimensions, and the abstainers and social drinkers almost ideally meeting the expectation of a mean normal population profile. Problem drinkers were also marked by high life impact scores, low self-esteem, high self-awareness, low perceived parental acceptance and high amount of rejection by the parents, and various indicators of a stressful and less rewarding school environment. Again, the heavy drinkers were positioned on an intermediate level on some of these scales, whereas the abstainers and social drinkers scored more normally. CONCLUSION: These findings support the validity of the distinction of various adolescent alcohol use types.  相似文献   
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Complex chromosome rearrangements are only rarely seen in constitutional karyotypes. A case of prenatally detected trisomy 9p with trisomy 10p originating from adjacent segregation of a maternal complex chromosome rearrangement is reported. Ultrasound examination at 18 weeks of gestation showed cleft lip palate, club feet, structural anomalies of the cerebellum and cystic kidneys. Cytogenetic analysis of amnion cells revealed a female fetus with 47,XX,+der(9). FISH analyses together with parental karyotyping demonstrated the fetal additional chromosome to originate from malsegregation of a maternal complex chromosomal rearrangement. The mother is carrier of a balanced translocation t(4;10;9) (q12; p11;q13). Postmortem examination of the fetus showed nose anomalies, cleft lip palate, low set ears, club feet, lung anomalies, cystic kidney and aplasia of the uterus. Reporting of such rare cases is important in order to enable this information to be used for genetic counselling in similar situations.  相似文献   
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