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Kathryn Nichol Sean P. Deeny Joseph Seif Kevin Camaclang Carl W. Cotman 《Alzheimer's & dementia》2009,5(4):287-294
BackgroundHuman studies on exercise, cognition, and apolipoprotein E (APOE) genotype show that ε4 carriers may benefit from regular physical activity.MethodsWe examined voluntary wheel-running, memory, and hippocampal plasticity in APOE ε3 and APOE ε4 transgenic mice at 10–12 months of age.ResultsSedentary ε4 mice exhibited deficits in cognition on the radial-arm water maze (RAWM), a task dependent on the hippocampus. Six weeks of wheel-running in ε4 mice resulted in improvements on the RAWM to the level of ε3 mice. Hippocampal brain-derived neurotrophic factor (BDNF) levels were similar in ε3 and ε4 mice, and after exercise BDNF was similarly increased in both ε3 and ε4 mice. In sedentary ε4 mice, tyrosine kinase B (Trk B) receptors were reduced by 50%. Exercise restored Trk B in ε4 mice to the level of ε3 mice, and in ε4 mice, exercise dramatically increased synaptophysin, a marker of synaptic function.ConclusionsOur results support the hypothesis that exercise can improve cognitive function, particularly in ε4 carriers. 相似文献
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J. Hucke R. L. Campo F. De Bruyne A. Abou Freikha 《Archives of gynecology and obstetrics》1993,254(1-4):421-423
Ohne Zusammenfassung 相似文献
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M A el-Barrawy S A Hafez S A Mokhtar M A Abou Rayan 《The Journal of the Egyptian Public Health Association》1991,66(1-2):279-289
This study evaluates the sensitivity and specificity of an enzyme-linked immunosorbent assay (ELISA) for the detection of antibodies against Mycobacterium tuberculosis antigen. Twenty seven of the 35 patients with pulmonary tuberculosis had positive serology with an antibody titre of 10 nineteen of them had positive serology with an antibody titre of 100. All the 27 patients with positive serology were either smear or culture positive or both. Twenty six of the 35 control group had negative serology and 9 had positive serology with an antibody titre of 10. The test has a sensitivity of 77.14% and a specificity of 74.29%. 相似文献
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A N Nasi A M Mangoud M I Assaf M I Abou Zeid M M Azab 《The Journal of the Egyptian Public Health Association》1992,67(5-6):685-695
Serum samples were collected from 40 patients with enlarged lymph nodes. Lymph node and bone marrow biopsies were performed and processed as usual. Tumor necrosis factor-alpha (TNF alpha) was determined in the sera by factor test human TNF alpha ELISA kit. Histopathological studies of lymph node and bone marrow biopsies were evaluated. The data obtained from this study showed that bone marrow was involved in only 5 patients and their TNF showed the lowest level in this study with a mean level 50 pg/ml. The highest level of TNF occurred in cases with granulomatous lymphadenitis (124 pg/ml) followed by reactive lymphadenitis (105 pg/ml). It can be considered that TNF reflects the immune status of the patient and its study in the serum can be of help in evaluating the progress of the disease. An extended study is need to evaluate the role of TNF-alpha as a prognostic marker in malignancy. 相似文献
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M Seif el Nasr B Peruche C Rossberg H D Mennel J Krieglstein 《European journal of pharmacology》1990,185(1):19-24
The purpose of the present study was to test whether the anticonvulsant, memantine (1-amino-3,5-dimethyladamantane), can protect neurons against hypoxic or ischemic damage. To this end, we used a rat model of transient forebrain ischemia and cultured neurons from chick embryo cerebral hemispheres. Ischemia was induced for 10 min by clamping both carotid arteries and lowering the mean arterial blood pressure to 40 mm Hg; the rats were allowed to recover for 7 days. Cultured neurons were made hypoxic with 1 mmol/l NaCN added to the incubation medium for 30 min followed by a recovery period of 3 days. The possible effects of memantine were compared with those produced by a typical non-competitive NMDA antagonist, dizocilpine. Similar effects were obtained with both drugs. The drugs reduced the damage caused by transient ischemia to neurons of the hippocampal CA1 subfield. Memantine (10 and 20 mg/kg) had a dose-dependent effect when administered intraperitoneally to the rats 1 h before ischemia. Dizocilpine was active in this model at a dosage of 1 mg/kg. When administered after ischemia, 10 mg/kg memantine significantly protected CA1 neurons against ischemic damage. Furthermore, the drugs protected cultured neurons against hypoxic damage. The lowest effective concentration was 0.1 mumol/l for dizocilpine and 1 mumol/l for memantine. Thus, memantine possesses neuroprotective activity but is less potent than dizocilpine. 相似文献
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Human ovarian granulosa cells and follicular fluid indices: the relationship to oocyte maturity and fertilization in vitro 总被引:1,自引:0,他引:1
The study investigates the correlation between oocyte maturity and
fertilization and a variety of hormonal parameters in follicular fluid and
ovarian granulosa cells. A methodology for purification of granulosa cells
from contaminating blood cells is also established. A total of 63
follicular aspirates were collected at oocyte retrieval from 30 women
superovulated using the long luteinizing hormone- releasing hormone (LHRH
analogue)/human menopausal gonadotrophin regimen. Oestradiol, progesterone,
testosterone and human chorionic gonadotrophin (HCG) were quantified in
follicular fluid and granulosa cells were immunostained for human chorionic
gonadotrophin. Immunopurification of granulosa cells from contaminating
blood cells was performed. HCG in follicular fluid was significantly high
in follicles yielding immature (grade 3) oocytes (P=0.002); there was no
correlation with fertilization. Aspirates from follicles containing mature
(grade 1) oocytes and oocytes that subsequently fertilized had
significantly more granulosa cells immunobound to HCG (P < 0.001,
P=0.02). Moreover, the immunomagnetic purification technique provided
>98% pure population of granulosa cells. The data demonstrate that HCG
in follicular fluid and on granulosa cells may help to predict oocyte
maturity and fertilization. Furthermore, immunomagnetic beads provide a
reliable procedure for the purification of ovarian granulosa cells.
相似文献