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21.
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Psychoeducational findings among children treated for phenylketonuria   总被引:2,自引:0,他引:2  
Early treated phenylketonuric children who maintained a phe-restricted diet through age 10 were compared with those who discontinued the diet after age 6 on standardized tests of intelligence, school achievement, language, and perceptual skills. Mean IQ, reading, and spelling test scores improved between ages 6 and 10 for the on-diet children in comparison to those who were off diet. Mean scores on arithmetic, language, and perceptual skills, however, declined at a uniform rate for both groups. Children with PKU scored significantly lower than did their non-PKU siblings on tests of visual perception and visual-motor skills. We conclude that children with PKU should be maintained on a phe-restricted diet.  相似文献   
23.
New aspects of the etiology of tendon rupture   总被引:2,自引:0,他引:2  
Summary Native collagen fibers were exposed to different dynamic loads to simulate damage to tendons and ligaments relevant clinically and for sports medicine. The results suggest that the rupture of a tendon is caused at the submicroscopic fibrillar level. Not only slow or very fast elongation, but also very fast unloading of stretched fibers seems to be responsible for disseminated damage, which reduces the stability of a fiber. This damage is induced by intrafibrillar sliding processes, which occur only a few seconds before macroscopic slippage takes place. The significance of these events for the beginning and progress of repair in vivo is discussed. The conclusions are supported by simultaneous mechanical and radiological measurements, as well as by light- and electron-microscopic results.
Zusammenfassung Zur Simulierung klinisch bzw. sportmedizinisch relevanter Schäden an Sehnen und Bändern wurden native Kollagenfasern unterschiedlichen dynamischen Belastungen ausgesetzt. Die erzielten Ergebnisse sprechen dafür, die Ursachen einer Sehnenruptur im submikroskopischen fibrillären Bereich zu suchen. Sowohl eine langsame oder ruckartige Dehnung als auch eine ruckartige Entlastung zugbelasteter Fasern scheinen für das Auftreten disseminierter, die Faserstabilität reduzierender Gefügestörungen verantwortlich zu sein. Diese Gefügestörungen werden durch intrafibrilläre Gleitvorgänge eingeleitet, die an den noch voll belastbaren Fasern nur wenige Sekunden vor dem Einsetzen eines makroskopischen Faserfließens auftreten. Die Bedeutung dieser Ereignisse für den Beginn und Verlauf einer in vivo stattfindenden Reparationsphase wird erörtert. Die Aussagen werden gestützt durch simultane mechanische und röntgenographische Messungen sowie durch makroskopische, licht- und elektronenmikroskopische Befunde.
  相似文献   
24.
Two cloned DNA fragments, one derived from an alpha satellite subfamily common to chromosomes 13 and 21, and the other derived from a similar subfamily common to chromosomes 14 and 22, have been used as biotinylated probes in in situ hybridization studies. Under high stringency conditions, chromosome specific centromeric labelling can be obtained. The applications of this technique in clinical situations are illustrated on metaphases from a fetus with trisomy 21, a fetus with trisomy 13, and a child with clinical features of cat-eye syndrome.  相似文献   
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Fifty patients with refractory acute lymphoblastic leukemia underwent allogeneic bone marrow transplantation after conditioning with high-dose cytosine arabinoside and fractionated total body irradiation. Twenty-nine received intravenous immunoglobulin (i.v.Ig) infusion, primarily to prevent cytomegalovirus infection, and 21 did not. The two groups were biologically comparable. Seven (24.5%) of the i.v.Ig-treated and 14 (66.7%) of the non-i.v.Ig-treated patients developed systemic viral, fungal or bacterial infections and/or interstitial pneumonitis (p less than 0.005), which were fatal in three and 12 cases respectively (p less than 0.001). Currently, 23 (79.3%) of the 29 i.v.Ig-treated and eight (38.1%) of the 21 non-i.v.Ig-treated patients are alive and well (p less than 0.01). We conclude that prophylactic i.v.Ig infusions may reduce the frequency of all forms of serious infection in patients with acute lymphoblastic leukemia undergoing allogeneic marrow transplantation, and thereby improve their survival expectation.  相似文献   
27.
This paper reports a case study of a 10-year-old girl exhibiting symptoms of a Zimmermann-Laband syndrome (ZLS), including an ocular involvement not previously observed. In addition to the case reported, we have also discovered 21 patients described in the literature. Major clinical findings, defined as being present in more than 75% of the cases under discussion, are presented.  相似文献   
28.
Specific receptors for vitamin D have been identified in human muscle tissue. Cross-sectional studies show that elderly persons with higher vitamin D serum levels have increased muscle strength and a lower number of falls. We hypothesized that vitamin D and calcium supplementation would improve musculoskeletal function and decrease falls. In a double-blind randomized controlled trial, we studied 122 elderly women (mean age, 85.3 years; range, 63-99 years) in long-stay geriatric care. Participants received 1200 mg calcium plus 800 IU cholecalciferol (Cal+D-group; n = 62) or 1200 mg calcium (Cal-group; n = 60) per day over a 12-week treatment period. The number of falls per person (0, 1, 2-5, 6-7, >7 falls) was compared between the treatment groups. In an intention to treat analysis, a Poisson regression model was used to compare falls after controlling for age, number of falls in a 6-week pretreatment period, and baseline 25-hydroxyvitamin D and 1,25-dihydroxyvitamin D serum concentrations. Among fallers in the treatment period, crude excessive fall rate (treatment - pretreatment falls) was compared between treatment groups. Change in musculoskeletal function (summed score of knee flexor and extensor strength, grip strength, and the timed up&go test) was measured as a secondary outcome. Among subjects in the Cal+D-group, there were significant increases in median serum 25-hydroxyvitamin D (+71%) and 1,25-dihydroxyvitamin D (+8%). Before treatment, mean observed number of falls per person per week was 0.059 in the Cal+D-group and 0.056 in the Cal-group. In the 12-week treatment period, mean number of falls per person per week was 0.034 in the Cal+D-group and 0.076 in the Cal-group. After adjustment, Cal+D-treatment accounted for a 49% reduction of falls (95% CI, 14-71%; p < 0.01) based on the fall categories stated above. Among fallers of the treatment period, the crude average number of excessive falls was significantly higher in the Cal-group (p = 0.045). Musculoskeletal function improved significantly in the Cal+D-group (p = 0.0094). A single intervention with vitamin D plus calcium over a 3-month period reduced the risk of falling by 49% compared with calcium alone. Over this short-term intervention, recurrent fallers seem to benefit most by the treatment. The impact of vitamin D on falls might be explained by the observed improvement in musculoskeletal function.  相似文献   
29.
Nitric oxide (NO) is a free radical produced by several lung cells via the enzyme nitric oxide synthetase (NOS) and can be easily measured in exhaled air by chemiluminescence analysis. As the iso-enzyme iNOS may be induced by cytokines and endotoxin, NO is elevated in several chronic inflammatory airway diseases. Prior to using exhaled nitric oxide (eNO) as a non-invasive marker of airway inflammation in daily routine, the role of possibly influencing factors such as age, time of the day, smoking exposure and intra-individual variability have to be clarified. NO concentrations were measured in 107 healthy children aged 4–18 years at an expiratory flow of 184 ml/s. Spirometry and a skin-prick test were performed and a questionnaire on family history of atopy, personal symptoms of atopic disease and smoke exposure was completed. For intra-individual variability nitric oxide was measured in six children three times daily on 6 consecutive days. Median eNO concentration was 5.7 p.p.b., and increased significantly with age but did not vary with gender. No correlation was found between eNO and smoke exposure, positive skin-prick test, FEV 1, MEF25 and time of the day. There was no circadian rhythm found in the six children measured on 6 consecutive days, but the eNO showed an intra-individual coefficient of variation of 25.9%. With the help of a two-compartment model of the lung the alveolar NO concentration was estimated to be 4.1 p.p.b and was shown to be constant with age, whereas the airway part of NO steadily increased with age. When comparing eNO values with standardized measurement techniques, the age of the children and the large intra-subject coefficient of variation have to be taken into account, whereas in healthy children subject-specific factors such as atopic history, gender and skin test reactivity did not affect eNO measurement.  相似文献   
30.
OBJECTIVE: The objective of this study was to compare 2 preparation techniques performed under simulated clinical conditions with extended apical enlargement following determination of the optimal apical preparation size (APS). STUDY DESIGN: After preflaring 240 root canals, APS was evaluated as outlined in Part I. The apical portion was shaped to APS either with rotary NiTi Lightspeed instruments (LS) or NiTi hand instruments (HA) using the balanced force technique in a phantom head. After sectioning the apical area at 3 levels, every cross section was analyzed microscopically for circumferential removal of canal wall dentine. Loss of working length, instrument separation, and perforation were additionally recorded. RESULTS: In 70% (LS) and 69% (HA) of the root canals, 2 of 3 levels demonstrated that the root canal dentin was cut circumferentially. Neither loss of working length nor perforation occurred in both groups. Four LS instruments separated. CONCLUSIONS: APS frequently results in a nearly complete apical preparation regardless of the preparation techniques. In a few cases apical enlargement to APS does not achieve complete cutting of the canal walls. There was a rather slight risk of serious procedural errors.  相似文献   
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