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Does altered biomechanics cause marrow edema?   总被引:21,自引:0,他引:21  
Schweitzer  ME; White  LM 《Radiology》1996,198(3):851
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The International Conference on Primary Health Care, meeting in Alma-Ata, in the Soviet Union, September 12, 1978, expressed the need for urgent action by all governments, all health and development workers and the world community, to protect and promote the health of all people of the world. The world was caught by the phrase which emerged from this conference, Health For All by the Year 2000 and many have examined the articles of the Alma-Ata declaration and tried to implement them in their corner of the world. This paper describes a community-based smoking-cessation program which was implemented in the province of Nova Scotia, Canada, during the years 1980–1984. Primary to this project was the belief that people have the right and the duty to participate individually and collectively in planning and implementing their health care. This paper describes one community's effort in putting this belief into practice.Carol Smillie, B.N. BE.d. M.S.c. is an Assistant Professor at the School of Nursing, Dalhousie University, Halifax, Nova Scotia, Canada B3H 3J5, Katherine Coffin, BA, MEd is the Program Officer, Nova Scotia Office, Health Promotion Directorate Health and Welfare Canada, 5251 Duke Street, Halifax, Nova Scotia. Canada B3J 1P3. Kathryn Porter, B.A. (Gen)., is the Information and Education Coordinator, Nova Scotia Division Canadian Cancer Society. Brenda Ryan, B.A., M.B.A. is Program Evaluation Analysist, Nova Scotia Department of Health, 6088 Hollis Street, Halifax. Nova Scotia, Canada. This Project was funded by Health and Welfare Canada, Nova Scotia Department of Health, Nova Scotia Division Canadian Cancer Society, Requests for reprints should be addressed to: Professor Carol Smillie.  相似文献   
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Vaccination against smallpox is again considered in order to face a possible bioterrorist threat, but the nature and the level of the immune response needed to protect a person from smallpox after vaccination are not totally understood. Therefore, simple, rapid, and accurate assays to evaluate the immune response to vaccinia virus need to be developed. Neutralization assays are usually considered good predictors of vaccine efficacy and more informative with regard to protection than binding assays. Currently, the presence of neutralizing antibodies to vaccinia virus is measured using a plaque reduction neutralization test, but this method is time-consuming and labor-intensive and has a subjective readout. Here, we describe an innovative neutralization assay based on a modified vaccinia virus Ankara (MVA) vector expressing the green fluorescent protein (MVA-gfp). This MVA-gfp neutralization assay is rapid and sensitive and has a high-throughput potential. Thus, it is suitable to monitor the immune response and eventually the efficacy of a large campaign of vaccination against smallpox and to study the vector-specific immune response in clinical trials that use genetically engineered vaccinia viruses. Most importantly, application of the highly attenuated MVA eliminates the safety concern in using the replication-competent vaccinia virus in the standard clinical laboratory.  相似文献   
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Gene expression profiling using microarrays (rat-specific array RG-U34A, Affymetrix, U.S.A.) was employed for the investigation of: (1) hormonal regulation of renal function and (2) nephrotoxicity. For this purpose about 8,800 genes were analysed in kidney and, additionally, in liver tissue.

Ad 1.) Kidney functions develop during postnatal life. Thus, in vivo transport and accumulation of p-aminohippurate (PAH) was investigated on renal cortical slices (RCS) from 10- and 55-day-old rats. The animals were treated with dexamethasone (DEXA; 60 μg/100 g b.wt./day) for 3 days, which caused a significant reduction in the accumulation of PAH in 10-day-old rats (42 ± 5% whereas it was only slightly reduced in 55-day-old rats (70 ± 8%). To further clarify the regulation of renal function by DEXA, results were compared with those obtained previously after in vitro stimulation with DEXA. RCS were incubated for 24 hours in DEXA-containing medium (10−9 M). Under these conditions DEXA significantly increased the PAH uptake capacity in RCS obtained from 10- and 55-day-old rats up to 126 and 136%, respectively. Thus a stimulation of tubular transport capacity is possible in vitro. The effect of DEXA treatment on the gene expression of the kidney (in vivo) was moderate. Focussing especially on transporters, ion channels, ATPases, glucuronyltransferases, glutathione-S-transferase and cytochrome P450, the expression of only few genes were significantly changed (3 to 50-fold up- or down-regulation). Moreover, distinct age differences were found after in vivo administration of DEXA. The investigation of in vitro effects of DEXA is currently been performed.

Ad 2.) The kidney is threatened by nephrotoxins because of its ability to accumulate them. We used a single administration of uranyl nitrate (UN; 0.5 mg/100 g b.wt.) as a model for chronic renal failure (CRF). Clearance experiments were performed 10 weeks after UN administration (maximal symptoms of CRF) in adult female rats. As expected, UN induced interstitial cicatrices with reduced GFR and diminished PAH transport capacity. Despite the impressive morphological and functional changes in the kidney after exposure to UN, the gene expression profiles in the kidneys were only minimally affected: we found significantly changed expression levels for only 20 genes (5 genes were up-regulated [e.g. transgelin], 15 down-regulated [among these the Na-K-Cl-symporter, insulin-like growth factor, kallikrein, and ornithine decarboxylase). The lack of agreement between gene expression data and the nephrotoxic effects of UN can probably be explained by the long time interval between dosing and the assessment of the effect. The results confirm that primary genomic responses are likely to be strongest transiently after exposure and then decrease in intensity.  相似文献   

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The Analytab Products, Inc. (API), anaerobic multitest microsystem (MICRO) was compared with the Center for Disease Control conventional (CONV) thioglycolate (supplemented with hemin and vitamin K1) system and with pre-reduced anaerobically sterilized (PRAS) media as recommended by the Virginia Polytechnic Institute. Growth from a solid medium was suspended to produce standard inocula. Substrates included 16 carbohydrates, indole, urea, gelatin, and esculin. API strips were inoculated in air and incubated in GasPak (BBL) jars. MICRO tests were read at 1 and 2 days. CONV tests at 1, 2, and 7 days, and PRAS tests at 3 weeks. One hundred thirty well-characterized strains of anaerobes (76 gram-negative rods, 16 cocci, 26 gram-positive nonsporeforming rods, and 12 clostridia), including 48 reference strains, were studied. Of 2,600 tests performed, 2,085 (80.2%) showed agreement with all three methods. There was 90.9% agreement between the MICRO and CONV, 84.9% between the MICRO and PRAS, and 84.6% between the CONV and PRAS tests. All MICRO tests were reliable except for indole, which was not sensitive enough, and gelatin, which was very insensitive. The MICRO system permits performance of biochemical tests at the workbench in the average clinical laboratory without the need for expensive equipment and time-consuming procedures.  相似文献   
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In-vitro maturation (IVM) of oocytes is a promising technique to reduce the costs and avert the side-effects of gonadotrophin stimulation for in-vitro fertilization (IVF). The pregnancy rates from oocytes matured in vitro are much lower than those of in-vivo stimulation cycles indicating that optimization of IVM remains a challenge. Therefore, we investigated the effect of supplementation of the medium with gonadotrophins, oestradiol and epidermal growth factor (EGF) and the effect of retaining or removing the cumulus cells on nuclear and cytoplasmic maturation of immature oocytes. Human germinal vesicle (GV) oocytes obtained after gonadotrophin stimulation for intracytoplasmic sperm injection (ICSI) were cultured in a complex defined medium either supplemented with gonadotrophins, oestradiol and physiological concentrations of EGF (2 ng/ml) or gonadotrophins and oestradiol alone. The cumulus cells were either removed or kept intact. In GV stage oocytes cultured without cumulus (group I) significantly more oocytes reached the metaphase II (MII) stage at 30 h in media supplemented with EGF (64.3 versus 33.9%, P < 0.003). For oocytes cultured with intact cumulus (group II), more oocytes reached MII at 30 h than in group I, but there was no difference in medium with or without EGF supplementation (81.8 and 79.8% respectively). Cytoplasmic maturation of MII oocytes was judged from their capability to activate and fertilize after ICSI. In group I, the rates of activation and normal fertilization were similar. However, in group II, significantly more oocytes underwent normal fertilization in the EGF-supplemented than the unsupplemented group (71.7 versus 45.6%, P < 0.05). The cleavage rates of the fertilized oocytes were similar in the sibling oocyte subgroups cultured with or without EGF supplementation, but the overall cleavage rates were higher in cumulus-intact compared to cumulus-denuded oocytes (88.9 versus 47.8%, P < 0.001). Thus, supplementation of the maturation medium with EGF and maintenance of the cumulus during culture improve the nuclear and cytoplasmic maturation of human oocytes in vitro.   相似文献   
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