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991.
992.
The aim of the current study is to investigate the prevalence of hypovitaminosis D in Lebanese subjects, its robust predictors, evaluate the relationship between 25 hydroxy vitamin D [25(OH)D] and parathyroid hormone levels, and derive desirable vitamin D levels, based on a large hospital laboratory database spanning all age groups.  相似文献   
993.
Emerging infectious diseases are some of modern society’s greatest threats. Like some great construction efforts designed to protect mankind, current public health measures against these emerging pathogens have not always been successful. This paper highlights the importance of embracing new interdisciplinary approaches towards emerging pathogen threats. One such approach, termed One Health, is quickly being embraced by professional organizations and public health institutions across the world as a way forward. This paper briefly discusses the above problems and preliminary steps taken by Chinese academic institutions to embrace the One Health approach.  相似文献   
994.
Blood superoxide dismutase (SOD) and plasma malondialdehyde (MDA) (an indicator of lipid peroxidation [LPO]) were determined in 97 randomly selected asbestos exposed workers (age range: 25–60 years, mean duration of exposures 19.8 ± 8.3 years) and in 42 healthy male controls. MDA, SOD, and MDA/SOD ratio in asbestos exposed workers were significantly higher than in controls. Among both the controls and exposed workers neither age nor smoking was related to SOD or MDA levels. SOD was significantly positively correlated with MDA among the exposed workers. Such correlation was not observed among the controls. SOD but not MDA was significantly positively correlated with the duration of exposure to asbestos. Mean levels of SOD or MDA in exposed workers with radiographic signs of lung fibrosis or pleural thickening did not differ significantly from those without such signs. The results confirm the possible involvement of LPO and development of anti-oxidant mechanism(s) of prolonged exposure to asbestos in humans. However, SOD seems not to be the essential anti-asbestos-induced LPO. Relation between these factors and lung fibrosis is still unclear.  相似文献   
995.
Various pottery materials were evaluated for possible use in manufacturing containers for radioactive waste. Their potential was examined from the viewpoints of the effectiveness of disposal and the changes induced in them by gamma rays. Samples of these materials were irradiated with high-energy neutrons and gamma rays in a reactor near its core. the physical and mechanical properties of the materials before and after gamma irradiation (in a 60Co gamma cell) were compared. The study showed that pottery materials are resistant to radiation. Therefore, they were proposed for manufacturing drums for disposal of radioactive waste of high gamma activity.  相似文献   
996.
We performed conventional cytogenetic analysis and fluorescence in situ hybridization in short-term cultures of normal and neoplastic kidney tissues. Cell populations carrying an extra chromosome 7 or an extra chromosome 10 as the only chromosome change could be identified in kidney tumors, mostly renal cell carcinomas, and in the surrounding kidney tissue, but not in nonneoplastic kidneys. To identify the type of cells displaying these aneuploidies, we performed in situ hybridization (ISH) with probes specific for the centromeric region of chromosomes 7 and 10 on frozen kidney tissue sections. Trisomy 7 and trisomy 10 were restricted to infiltrating inflammatory cells in the tumor as well as in the surrounding tissue. Trisomy 7 and trisomy 10 were also found in subpopulations of peripheral blood T cells of cancer patients and of normal individuals, as well as in the thymus of five normal fetuses (21-29 weeks), but not in noninvaded reactive lymph node sections of patients without malignancy. When lymphocytes were enriched from kidney tumors and surrounding tissue by either Ficoll/Hypaque density gradient or immunomagnetic selection with anti-CD3, anti-CD4, or anti-CD8 monoclonal antibodies, it was confirmed that they contained a high percentage of trisomy 7 and trisomy 10 cells. Further proof for T-lymphocyte origin of the trisomy 7 and trisomy 10 cells was obtained by simultaneous staining of lymphocytes isolated from tumor tissue with anti-CD3, anti-CD4, and anti-CD8 monoclonal antibodies and ISH. We conclude that trisomy 7 and trisomy 10, found in renal carcinomas and surrounding kidney tissue, characterize subpopulations of tumor-infiltrating lymphocytes. The biologic significance of this phenomenon is unknown and requires further investigation.  相似文献   
997.
Since December 1991, 25 consecutive symptomatic male patients with 26 varicoceles were treated by laparoscopic ligation of internal spermatic veins under general anaesthesia. Twenty-one patients had either scrotal discomfort or painful swelling and four patients presented with infertility. The mean follow-up period is 5 months (range 3 weeks to 9 months). The procedure has provided a satisfactory outcome in 19 out of 21 patients (90.5%) with scrotal symptoms. Of the four patients presenting with infertility due to oligospermia, three had significantly elevated sperm counts at 3 months which resulted in one pregnancy. So far there has been no recurrence of the varicocele. The main potential advantage of the laparoscopic approach is better visualisation of the anatomy, especially the testicular artery and the collateral venous circulation at the level of the internal inguinal ring. In addition to being less invasive with implied benefits, the endoscopic procedure has enabled identification of multiple veins in 22 out of 26 (84.6%) varicoceles in our series.  相似文献   
998.
999.
Experimental autoimmune encephalomyelitis (EAE) is a model for multiple sclerosis (MS). However, MS is a chronic, relapsing and demyelinating disease, whereas EAE in rats is typically a brief and monophasic disorder showing little demyelination. We demonstrate here that DA rats develop severe, protracted and relapsing EAE (SPR-EAE) after a subcutaneous immunization at the tail base with syngeneic spinal cord and incomplete Freund's adjuvant (IFA). The neurological deficits were accompanied by demyelinating inflammatory lesions in the spinal cord, with infiltrating T lymphocytes and perivascular deposition of immunoglobulins and complement. The induction of SPR-EAE was associated with humoral autoreactivity to myelin oligodendrocyte glycoprotein (MOG) and cellular autoreactivity to the rat myelin basic protein (MBP) peptides 69–87 and 87–101. These two peptides, as well as whole rat MBP, were encephalitogenic. In conclusion, we believe that the presently described demyelinating SPR-EAE represents a useful model for MS.  相似文献   
1000.
AIM: To compare the effectiveness of an interactive multimedia courseware package versus standard lectures regarding knowledge, understanding, and transfer of content, as well as problem-solving skills in orthodontics. METHODS: Pre- and post-test assessments of final-year dental students (n = 26), who either used an interactive multimedia courseware package (n = 15) or attended standard lectures (n = 11) on equivalent material of the undergraduate orthodontic curriculum were carried out. Both groups were tested by written and multiple-choice questions covering knowledge, understanding, and application areas in the curriculum. A one-way anova was carried out in order to check statistical difference between the two groups. The P-value was set at 0.05. RESULTS: There was no difference in prior knowledge between the groups at baseline. Generally, no significant difference was seen between the two groups in relation to answers to questions about knowledge, understanding, and application in the orthodontic curriculum. However, both groups improved their scores after the course. In one question investigating the extent of understanding the instructional content of the multidisciplinary orthodontic treatment, the multimedia courseware package group scored significantly better. CONCLUSION: In this study, the instructional interactive multimedia program was found to be at least as effective as the standard lecture of the orthodontic curriculum for undergraduate training in orthodontics.  相似文献   
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