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1.
Ten groups of 14 immunosuppressed NMRI-mice (nu/nu) were raised and kept under germ-reduced conditions. The control animals were fed a germ-reduced diet, nine other groups received the same diet with selegiline (CAS 14611-51-9, Deprenyl) or lipoic acid (thioctic acid, CAS 62-46-4) admixed at various amounts. The 50% survival rate, the total life span of each group and the areas under the curves were determined to evaluate life expectancy as compared to the controls. The racemate of lipoic acid at high dosage (350 mg/kg body weight) reduced the life span significantly. The S(-)-enantiomer of lipoic acid (75 mg/kg body weight) increased the 50% survival rate, whereas the physiologic R(+)-enantiomer (9 mg/kg body weight) expanded the total life span of its group. Alteration of only one out of three parameters was not considered significant. All other groups except for one did not differ from controls: only animals which obtained 75 micrograms selegiline per kg of body weight and per day exerted increased life expectancies by all three parameters. This group exhibited also in statistical evaluation a significantly (p < 0.05) prolongated survival time up to about 200% as compared to the control animals. 相似文献
2.
To address the hypothesis that tumor necrosis factor (TNF)-alpha has a role in obesity-associated insulin resistance or the regulation of in vivo lipid metabolism, mice with targeted disruption of the TNF-alpha gene were generated and studied. The absence of TNF-alpha protein in TNF-null (-/-) mice was confirmed. Lean or obese (gold-thioglucose [GTG]-injected) homozygous (-/-) mice were compared with lean or obese age- and sex-matched wild-type (+/+) mice derived from the same line at 13, 19, and 28 weeks of age. The following parameters were significantly affected in lean -/- versus +/+ mice: Body weight was not affected until week 28 (decreased by 14%); epididymal fat pad weight also decreased (25%) at this time, as did percentage body fat (16%), while percentage body protein was increased 13%. Fed plasma insulin levels decreased 47% (28 weeks), triglyceride levels decreased (all three ages; maximum 35% at 19 weeks), and fed plasma leptin decreased 33% (28 weeks). Fasting glucose was slightly (10%) reduced, but the glucose response to an oral glucose tolerance test (OGTT) was not affected. There was a trend (NS) toward increased total adipose tissue lipoprotein lipase in -/- versus +/+ mice. GTG-treatment resulted in obese -/- and +/+ mice with equal mean body weights (42 and 58% increased weight versus lean mice). The following parameters were significantly different in obese -/- mice: fasting plasma glucose decreased 13% (28 weeks), fed plasma insulin decreased 67% (28 weeks), and insulin response to OGTT was decreased by 50%. For both groups of obese mice, glucose levels during the OGTT were substantially increased compared with those in lean mice; however, mean stimulated glucose levels were 20% lower in obese -/- versus +/+ mice. We conclude 1) that TNF-alpha functions to regulate plasma triglycerides and body adiposity and 2) that although TNF-alpha contributes to reduced insulin sensitivity in older or obese mice, the absence of TNF-alpha is not sufficient to substantially protect against insulin resistance in the GTG hyperphagic model of rodent obesity. 相似文献
3.
DI Timokhin AV Istomin TS Shushkova TG Voronel' IG Mikha?lov 《Canadian Metallurgical Quarterly》1997,(2):19-21
Based on generalization and analysis of instructions and guidelines for therapeutical and prophylactic diets of workers, ways of its optimization were proposed, by using bifide-containing acid dairy products as a preventive agent against possible occupational diseases caused by occupational factors. 相似文献
4.
Cancer statistics, 1993 总被引:1,自引:0,他引:1
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1. alpha-toxin of Staphylococcus aureus readily permeabilized rat uterine smooth muscle after incubation for a short time. 2. The permeabilized muscle responded to Ca2+ dose-dependently and repeatedly in the same manner. 3. The threshold concentration of Ca2+ for contraction was 0.1-0.3 microM and the maximal contraction was achieved with 1 or 3 microM Ca2+. 4. GTP gamma S or GTP augmented the contractile response to Ca2+. 5. GDP beta S or GDP suppressed the contraction. 6. The role of GTP-binding protein in sensitization of Ca(2+)-induced contractile response of smooth muscle is discussed. 相似文献
7.
BACKGROUND: Noncutaneous psammomatous melanotic schwannoma has recently been reported as an unusual component of Carney's complex (myxomas, spotty pigmentation, and endocrinopathy). The most common locations for this lesion include peripheral nerve roots and the gastrointestinal tract. OBSERVATIONS: A cutaneous psammomatous melanotic schwannoma is reported in a patient with known Carney's complex. This neoplasm was pseudoencapsulated, with epithelioid to spindle-shaped cells and no nuclear atypia. Immunostaining was positive for S100 protein and vimentin, as well for HMB-45 antibody. Electron microscopy showed melanosomes in cytoplasmic processes of cells that were ensheathed by layers of reduplicated basal lamina. CONCLUSIONS: Location in the superficial soft tissues is extremely unusual for psammomatous melanotic schwannomas. Recognition of this new cutaneous marker as a part of this complex may aid in identification of individuals at risk for cardiac myxomas. It is also important that this lesion is not mistaken for melanoma, given the strong HMB-45 positivity. 相似文献
8.
M Burkhardt T Kupper S Hean R Haag P Schmid M Kohler M Boller 《Water science and technology》2007,56(12):63-67
There is increasing concern about diffuse pollution of aquatic systems by biocides used in urban areas. We investigated sources and pathways of biocides significant for the pollution of storm water runoff. Main sources seem to be building envelopes, i.e. facades (paints, plasters) and roof sealing membranes. First results from a defined urban catchment drained by a separated sewer system without any agricultural activities reveal a substantial occurrence. Even after the first flush, concentrations of terbutryn, carbendazim, mecoprop as well as Irgarol 1051 and its metabolite exceeded the Swiss water quality standard of 0.1 microg/L. In laboratory experiments, leaching of mecoprop used as a root protection agent in bitumen sheets for roof waterproofing was determined. The concentrations differed in 16 different sheets two orders of magnitude, depending on the product composition. Using optimized products, it is expected to be the most efficient and sustainable way to reduce the environmental impact. To understand transport dynamics and environmental risk, further storm water events will be analyzed. Based on the ongoing project URBIC, first measures will be proposed to limit the release to surface and ground water. 相似文献
9.
In Study One, a sample of 230 college students were asked to estimate the abuse potential and lethality of commonly used recreational drugs, both licit and illicit. In Study Two, a sample of 103 degreed nurses were asked to estimate the lethality of the same recreational drugs. The findings indicate that the illicit drugs under consideration are perceived as presenting the greatest danger to the user and that dangers attributed to the use of licit recreational drugs are generally minimized. Perception of danger was found to be unaffected by exposure to reported drug education programs. Results are discussed in terms of public health implications. 相似文献
10.