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991.
A longitudinal study was conducted to investigate changes in women's mental and physical health around the time of childbirth, and to determine whether health was related to length of maternity leave. Thirty-seven married, employed first-time mothers completed questionnaires during pregnancy, and again at 6 weeks, 3 months, and 6 months postpartum. Results showed that, from pregnancy to the 6th postpartum month, the number of days that mothers were ill because of infections steadily increased. In addition, depressive symptoms for new mothers rose from pregnancy to the 6th week postpartum, and declined thereafter. For women who did not return to work during the period of the study, a significant decline in depressive symptoms was observed from the prenatal period through the 6th postpartum month. These findings demonstrate significant changes in mental and physical health for this group of first-time mothers.  相似文献   
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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   
995.
A quantitative assay for ALZ-50 immunoreactivity was evaluated in samples of superior temporal gyrus taken at autopsy from 13 Alzheimer patients and 11 controls. The assayable immunoreactivity appears to be stable for at least 24 hours postmortem but was lost with formalin fixation. The mean value of the Alzheimer patients was tenfold higher than that of the controls (P less than .002). The values of four Alzheimer samples overlapped with the low levels seen in controls, but no controls had elevated levels. In this sample population, therefore, the assay had a sensitivity of 69% and specificity of 100%.  相似文献   
996.
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   
997.
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   
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999.
This series of articles, Managing Your Academic Career, presents ways to intentionally improve your teaching. This first article explains the concept of becoming an intention teacher. Subsequent articles will deal with strategies that are useful in clinical teaching, such as preparing students to value and use research in practice, and providing feedback to students in the clinical setting.  相似文献   
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