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991.
Rats were chronically exposed to poisonous sodium selenite in concentrations 0.5 mg/kg b. m. for 10 weeks. As a result, hydroxyproline contents in blood serum increased, as well as its excretion with urine. It was proved that the procedure enhanced urinary glycosaminoglycane excretion and increased the contents of the protein-related glycosaminoglycanes in the serum. This was accompanied by increased quantities of keratane sulphate and heparin sulphate. The results confirmed that selenium poisonings influenced connective tissues.  相似文献   
992.
The head circumferences of 64 patients with Duchenne muscular dystrophy were measured and found to be greater than those of a normal population. The patients had relative, and in 12 cases, absolute macrocephaly. 47 of the 64 patients underwent intelligence testing and were found to be significantly intellectually impaired, particularly in verbal and language skills. There was no correlation between head circumference or absolute macrocephaly and intellectual performance. The cause of macrocephaly in these patients is unknown and its relevance to the aetiology of intellectual impairment in Duchenne muscular dystrophy is not yet clear.  相似文献   
993.
To compare nerve regeneration in young adult and aging mice, the right sciatic nerves of 6- and 24-month-old mice were crushed at the sciatic notch. Two weeks later, both groups of mice were perfused with an aldehyde solution, and, after additional fixation, the sciatic nerves were processed so that the transverse sections of each nerve subsequently studied by light and electron microscopy included the entire posterior tibial fascicle 5 mm distal to the crush site. The same level was sectioned in unoperated contralateral nerves; these nerves served as controls. Electron micrographs and the Bioquant Image Analysis System IV were used to measure areas of posterior tibial fascicles and count the number of myelinated axons, the number of unmyelinated axons, and their frequency in Schwann cell units. In aging mice, the total number of regenerating myelinated axons was significantly reduced, but totals of regenerating unmyelinated axons in aging and young adults did not differ significantly. In aging mice, the frequency of Schwann cells that contained a single unmyelinated axon was greater, suggesting that before myelination began, Schwann cell ensheathment of axons also was slowed. After axotomy by a crush injury, the area of the posterior tibial fascicle was less than that in young adults and the distal disintegration of myelin sheath remnants also appeared to be retarded. The results indicate that responses of neurons, axons, and Schwann cells could be important in slowing the regeneration of myelinated fibers found in sciatic nerves from aging mice.  相似文献   
994.
This paper reports results of an open prospective study of 26 patients who met DSM-III criteria for panic disorder or agoraphobia with panic attacks. Cognitive-behavioral treatment alone produced clinically and statistically significant improvement in panic symptoms, including both full-blown and limited symptom episodes. In addition, the treatment produced improvement in associated symptoms of phobic avoidance and generalized anxiety. This work provides further preliminary indication of the usefulness of cognitive-behavioral strategies as an alternative to medication in symptom-oriented treatments.  相似文献   
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A case of odontoameloblastoma affecting the left mandible is reported. Initially treated by conservative excision due to its small size, the lesion recurred after 18 months and was treated by radical excision and subsequent reconstruction by a rib graft.  相似文献   
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In this new radioimmunoassay system for determination of amatoxins in urine and plasma, a novel chemical approach is used for antigen and 125I-tracer production, based on a detoxified alpha-amanitin derivative (aldoamanitin). Total assay time, including data processing, is less than 100 min. The lowest detectable concentration is 1 microgram/L for urine, 0.1 microgram/L for plasma. In the clinically significant range, within-run CVs are less than 8%. This new 125I-based assay is a significant improvement over existing 3H technology in terms of speed, precision, and freedom from interference.  相似文献   
1000.
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