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81.
SG Shaughnessy J Hirsh M Bhandari JM Muir E Young JI Weitz 《Canadian Metallurgical Quarterly》1999,93(4):1231-1236
Although it is well established that long-term heparin therapy causes osteoporosis, it is unknown whether heparin-induced bone loss is reversible when heparin treatment is stopped. To address this question, we randomized rats to once daily subcutaneous injections of either unfractionated heparin (1.0 U/g or 0.5 U/g) or saline for 28 days and then followed the rats for an additional 28 days off treatment. Based on histomorphometric analysis of the distal third of the right femur proximal to the epiphyseal growth plate, 1.0 U/g heparin caused a 30% loss in cancellous bone volume over the first 28 days. This was accompanied by a 137% increase in osteoclast surface and a 60% decrease in both osteoblast and osteoid surface. One month after cessation of heparin treatment, no recovery in these parameters was observed. Similarly, serum levels of alkaline phosphatase, a biochemical marker of bone formation, which continued to decrease over the course of heparin treatment, showed no signs of recovery in the subsequent 28 days off treatment. To explore the mechanism responsible for the prolonged effect of heparin on bone, we repeated the experiment giving 125I-labeled heparin in place of unlabeled heparin. 125I-labeled heparin was found to accumulate in bone during the course of its administration, and be retained in bone for at least 56 days after stopping heparin treatment. These findings suggest that heparin-induced osteoporosis is not rapidly reversible because heparin is sequestered in bone for an extended period. 相似文献
82.
SV Chiplunkar MA Deshmukh JA Kode SG Gangal MG Deo 《Canadian Metallurgical Quarterly》1997,10(4):203-208
In cats and monkeys, we examined the parasympathetic component of the oculomotor complex, which directly innervates the ciliary muscle, using horseradish peroxidase (HRP). Labeled neurons of varying form and size were found in the Edinger-Westphal(EW) and the Perlia nuclei of the cat and in the anteromedian, EW, and Perlia nuclei of the monkey. Our study confirmed that a direct parasympathetic pathway exists from the midbrain to the ciliary muscles, and that accommodation is controlled in part by this direct link from the midsagittal region via a parasympathetic neuron of the oculomotor nuclear complex. 相似文献
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OBJECTIVE: The objectives of this study were to know the prevalence of hepatitis C virus (HCV) in a population of pregnant women, to evaluate the vertical transmission rates of HCV in a prospective study and to determine the repercussions and consequences in children born to infected mothers. PATIENTS AND METHODS: A total of 6556 pregnant women were tested for HCV antibodies from January 1993 to August 1995. We followed 50 babies born to infected mothers for at least 12 months (mean 15 months). Serological assays employed included a screening ELISA II confirmed with immunoblot. Viral detection was performed by qualitative and quantitative PCR for HCV-RNA. RESULTS: Fifty-nine pregnant women were AcHCV(+). This represents a seroprevalence of 0.9%. Of the 50 babies followed, 6 were PCR(+) and 44 were PCR(-). The risk of transmission is correlated with the titer of HCV-RNA in the mother. All mothers of infected babies were HIV (-). CONCLUSIONS: The rate of prevalence in our pregnant women population is 0.9%. We found a vertical transmission rate of 12%. The high serum HCV-RNA titers in the mothers are a risk factor of transmission of HCV. The viremia in the children does not predict the apparition of the clinical disease, although they can exhibit intermittent increases of transaminases. 相似文献
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In this thesis, Korean prisoners' health behavior and the characteristics of their medical utilization were surveyed and analysed. Because prisoners are inclined to be mediators of communicable diseases or unhealthy behaviors between prison institution and the outside world, health care for prisoners is directly related to the national population. Data were collected through a self-administered survey of 5 Korean prisons out of a total of 38 correctional facilities and analysed in accordance with a causal model based on a path frame, by serial multiple regressions on health behavior, health status, and medical utilization, etc. According to the survey analysis, while prisoners were generally concerned with their health much more than they were before imprisonment, they perceived that their health status had deteriorated after imprisonment, and that their need for health services was increasing gradually during their time in prison. In the path analysis on the causal relations among variables related to the prisoners' health status and medical utilization, the prisoners' characteristics affected their health concern and health behavior, and subsequently affected their health status and medical utilization, respectively. To sum up these exploratory studies on prisoners' health behavior and health service utilization, some efforts to organize a health care system embracing the correctional institution and health care administration should be made on the level of establishing a health care delivery system for special social groups like prisoners. 相似文献
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