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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.
V Anantharaman 《Canadian Metallurgical Quarterly》1997,38(3):95-97
The effect of various cytokines including rIL-1, rIL-2, rIL-3, rIL-4, rIL-6, and growth factors including rNGF, rILGF and rEPGF on the post transplant immunodeficiency after allogeneic bone marrow transplantation was explored in 8 patients. The results show that neither cytokine alone was able to increase the proliferative capability in post transplant lymphocytes, however, when added in conjunction a significant increase in PHA driven proliferation was noted. Any significant lack of growth factors is probably not the only cause of immunodeficiency post transplant, since addition of any of these compounds did not have any influence on the lymphocyte proliferation, and so the data presented here suggest that therapeutic application of any of the investigated cytokines or growth factors to such patients is unlikely to be successful in overcoming the defects of T cell function post grafting. 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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6.
BACKGROUND: Stroke is the number 3 killer in Singapore and a common contributor to morbidity statistics. This study was done to look at the profile of patients with acute stroke presenting to the Emergency Department, Singapore General Hospital, from 1 October to 31 November 1996. The data will help plan and guide future early interventional trials as well as look into possible areas of improvement in the multidisciplinary approach to stroke. METHOD: This is a retrospective study and patients records were traced using ICD-9 codes. A total of 309 patients were identified for the period of review; of this, the records of 240 patients were obtained (77.7%). RESULTS: The results revealed that local stroke patients are young (two-thirds are < 70 years) and live in high-rise accommodation (84.2%) with their families. The predominant risk factor was hypertension (80%) and weakness was the most common presentation (25%). Stroke patients are presenting at a later stage (only 16.7% presented within 6 hours of onset) and the average length of hospital stay was between 10 and 12 days. CONCLUSION: This study identified the multiple measures at various stages of the stroke chain, required to build up a concerted effort against Brain Attack. 相似文献
7.
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
8.
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
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.