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31.
We examined a nationally representative sample of 60 adult day care centers to describe the state of this evolving care modality after a decade's growth. Results indicate that day care centers can be categorized into three models of care, each of which serves a distinctive subpopulation. Model appropriateness was tested with analysis of variance of differences in participant characteristics. Services, staffing, costs, and other program features are contrasted among the three models.  相似文献   
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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   
34.
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   
35.
We hypothesized that in congestive heart failure (CHF) slow-twitch but not fast-twitch muscles exhibit decreased fatigue resistance in the sense of accelerated reduction of muscle force during activity. Experiments were carried out on anaesthetized rats 6 weeks after induction of myocardial infarction or a sham operation (Sham). Animals with left ventricular end-diastolic pressure (LVEDP) > 15 mmHg under anaesthesia were selected for the CHF group. There was no muscle atrophy in CHF. Force generation by in situ perfused soleus (Sol) or extensor digitorum longus (EDL) muscles was recorded during stimulation (trains at 5 Hz for 6 s (Sol) or 10 Hz for 1.5 s (EDL) at 10 or 2.5 s intervals, respectively) for 1 h in Sol and 10 min in EDL at 37 °C. Initial force was almost the same in Sol from CHF and Sham rats, but relaxation was slower in CHF. Relaxation times (95–5 % of peak force) were 177 ± 55 and 131 ± 44 ms in CHF and Sham, respectively, following the first stimulation train. After 2 min of stimulation the muscles transiently became slower and maximum relaxation times were 264 ± 71 and 220 ± 45 ms in CHF and Sham, respectively (   P < 0.05  ). After 60 min they recovered to 204 ± 60 and 122 ± 55 ms in CHF and Sham, respectively (   P < 0.05  ). In CHF but not in Sham rats the force of contraction of Sol declined from the second to the sixtieth minute to 70 % of peak force. The EDL of both CHF and Sham fatigued to 24–28 % of initial force, but no differences in contractility pattern were detected. Thus, slow-twitch muscle is severely affected in CHF by slower than normal relaxation and significantly reduced fatigue resistance, which may explain the sensation of both muscle stiffness and fatigue in CHF patients.  相似文献   
36.
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   
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Bilateral facial palsy is frequently linked with lyme disease. We report a patient with bilateral facial palsy due to Epstein-Barr virus infection but with Borrelia burgdorferi IgM in serum caused by polyclonal B-lymphocyte stimulation.  相似文献   
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