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71.
72.
Background
Physical activity has been associated with a decreased risk for breast cancer. The biological mechanismn(s) underlying the association between physical activity and breast cancer is not clear. Most prominent hypothesis is that physical activity may protect against breast cancer through reduced lifetime exposure to endogenous hormones either direct, or indirect by preventing overweight and abdominal adiposity. In order to get more insight in the causal pathway between physical activity and breast cancer risk, we designed the Sex Hormones and Physical Exercise (SHAPE) study. Purpose of SHAPE study is to examine the effects of a 1-year moderate-to-vigorous intensity exercise programme on endogenous hormone levels associated with breast cancer among sedentary postmenopausal women and whether the amount of total body fat or abdominal fat mediates the effects. 相似文献73.
Desialylated low density lipoprotein (LDL) is rapidly taken up and accumulated by both peripheral blood monocytes and cells isolated from human arterial intima consisting predominantly of smooth muscle cells. It is shown that thioglycollate (TG)-elicited mouse macrophages and mouse peritoneal macrophages stimulated with lipopolysaccharide (LPS) show increased expression of a membrane-bound, galactose-specific lectin that could be responsible for this uptake. In LPS-stimulated macrophages accumulation of desialylated LDL is increased ca. 2.6-fold. Accumulation of acetylated LDL in the same cells is reduced, suggesting that the galactose-specific lectin might be responsible for the uptake of desialylated LDL. Transfection of cells with the mouse macrophage Gal/GalNAc-specific lectin (MMGL) increased their capacity to take up asialofetuin (ASF) and, to a smaller extent, desialylated LDL. The uptake of desialylated LDL was small, most likely due to the high k(d) of MMGL for biantennary oligosaccharides as found on LDL, and low concentration of LDL achieved in tissue culture experiments. The data suggest that the expression of galactose-specific lectins can be elevated under inflammatory conditions, and that these receptors could contribute to foam cell formation under conditions of high desialylated LDL concentration, as might be found in arterial intima. 相似文献
74.
Tuberculous otitis media is a rare but treatable disease; delay in its diagnosis usually leads to complications. In the last 15 years we have come across 18 cases of tuberculous otitis media, which presented various intra- and extracranial complications. In the past, tuberculous otitis media had always been considered a discrete disease, but it is possible that tuberculosis may coexist or secondarily affect an already discharging ear. The following discussion illustrates the complications and clinical problems encountered in tuberculous otitis media. 相似文献
75.
Sood D Katyal S Singh A Narula N Kathuria S Kaul TK Grewal A 《Regional anesthesia and pain medicine》2002,27(4):447; author reply 447
76.
This study was performed to explore the potential role of mitochondrial DNA mutations in the neurodegenerative process in amyotrophic lateral sclerosis (ALS). Using a semi-quantitative assay, a common mitochondrial DNA deletion mutation (mt DNA4977) was assayed in brain tissue obtained from six sporadic ALS patients and compared to four controls. In each brain, levels of this mutation were measured in a brain region affected by neurodegeneration, the motor cortex (Brodmann area 4), and compared to the temporal cortex (Brodmann area 17). In the ALS but not control brains, levels of mt DNA4977 were an average of more than 30-fold (range 15-250) higher in Brodmann area 4. These results support and extend those of previous studies implying that mitochondria may participate in the neurodegenerative process in ALS. 相似文献
77.
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79.
Phorbol ester-sensitive EL4 murine thymoma cells respond to phorbol 12-
myristate 13-acetate with activation of ERK mitogen-activated protein
kinases, synthesis of interleukin-2, and death, whereas phorbol ester-
resistant variants of this cell line do not exhibit these responses.
Additional aspects of the resistant phenotype were examined, using a
newly-established resistant cell line. Phorbol ester induced morphological
changes, ERK activation, calcium-dependent activation of the c-Jun
N-terminal kinase (JNK), interleukin-2 synthesis, and growth inhibition in
sensitive but not resistant cells. A series of protein kinase C activators
caused membrane translocation of protein kinase C's (PKCs) alpha, eta, and
theta in both cell lines. While PKC eta was expressed at higher levels in
sensitive than in resistant cells, overexpression of PKC eta did not
restore phorbol ester-induced ERK activation to resistant cells. In
sensitive cells, PKC activators had similar effects on cell viability and
ERK activation, but differed in their abilities to induce JNK activation
and interleukin-2 synthesis. PD 098059, an inhibitor of the mitogen
activated protein (MAP)/ERK kinase kinase MEK, partially inhibited ERK
activation and completely blocked phorbol ester-induced cell death in
sensitive cells. Thus MEK and/or ERK activation, but not JNK activation or
interleukin-2 synthesis, appears to be required for phorbol ester-induced
toxicity. Alterations in phorbol ester response pathways, rather than
altered expression of PKC isoforms, appear to confer phorbol ester
resistance to EL4 cells.
相似文献
80.
HM Karaka F Tokoglu M Kacar S Boyacigil 《Journal of Medical Imaging and Radiation Oncology》1997,41(2):179-180
A 54-year-old man with a unilocular hydatid cyst within the infero-posterior angle of the orbit and a 6-year-old male child with a unilocular hydatid cyst within the supero-medial angle of the orbit are presented. The retrobulbar cysts were diagnosed with computed tomography and ultrasonography and were treated after serologic confirmation. 相似文献