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41.
Platelet Aggregation Inhibiting and Anticoagulant Effects of Oligoamines, VII: Benzene-1,3,5-trialkanamines Seventeen title compounds were synthesized. Platelet aggregation induced by collagen in vitro is inhibited by 9 of them at IC50 = 2–4 μmol/L. Seven compounds depress the formation of fibrin to ≦ 25 % of normal in concentrations below 50 μmol/L. Compound 15 [4-(2-thienylbutyl)benzene-1,3,5-trimethanamine is the first oligoamine which shows anticoagulant and antiplatelet effects at the same concentration (25 μmol/L). 相似文献
42.
Reactive oxygen species: a breath of life or death? 总被引:7,自引:0,他引:7
New insights into cancer cell-specific biological pathways are urgently needed to promote development of rationally targeted therapeutics. Reactive oxygen species (ROS) and their role in cancer cell response to growth factor signaling and hypoxia are emerging as verdant areas of exploration on the road to discovering cancer's Achilles heel. One of the distinguishing and near-universal hallmarks of cancer growth is hypoxia. Unregulated cellular proliferation leads to formation of cellular masses that extend beyond the resting vasculature, resulting in oxygen and nutrient deprivation. The resulting hypoxia triggers a number of critical adaptations that enable cancer cell survival, including apoptosis suppression, altered glucose metabolism, and an angiogenic phenotype. Ironically, recent investigations suggest that oxygen depletion stimulates mitochondria to elaborate increased ROS, with subsequent activation of signaling pathways, such as hypoxia inducible factor 1alpha, that promote cancer cell survival and tumor growth. Because mitochondria are key organelles involved in chemotherapy-induced apoptosis induction, the relationship between mitochondria, ROS signaling, and activation of survival pathways under hypoxic conditions has been the subject of increased study. Insights into mechanisms involved in ROS signaling may offer novel avenues to facilitate discovery of cancer-specific therapies. Preclinical and clinical evaluation of agents that modify ROS signaling in cancer offers a novel avenue for intervention. This review will cover recent work in ROS-mediated signaling in cancer cells and its potential as a target for developmental therapeutics. 相似文献
43.
Phenytoin-induced gingival overgrowth is a recognized side effect in many cerebral palsy patients using diphenyl hydantoin for the control of seizures. Severe gingival overgrowth in these patients can affect normal masticatory function, lead to poor occlusal development, and compromise esthetics. This report addresses the complex nature of treating phenytoin-induced gingival overgrowth in a mentally retarded 20-year-old female patient. For this patient, full-mouth gingivectomy procedure was performed under general anesthesia in a single session. Post operative follow-up was uneventful. This article discusses major indications, contraindications, and protocols to be followed for periodontal surgical procedures done under general anesthesia. 相似文献
44.
PD Dr. U. Germer 《Der Gyn?kologe》2005,38(6):553-554
Ohne Zusammenfassung 相似文献
45.
Frank Huang-Chih Chou Tom Tung-Ping Su Pesus Chou Wen-Chen Ou-Yang Ming-Kun Lu I-Chia Chien 《台湾医志》2005,104(5):308-317
BACKGROUND AND PURPOSE: The catastrophic Chi-Chi earthquake of September 21, 1999 in Taiwan provided a unique opportunity to study the disaster's psychiatric impact on survivors. This study assessed the development of psychiatric disorders among residents in a Taiwanese village near the epicenter of the earthquake within 6 months of the disaster. METHODS: A total of 442 of the 602 actual living residents of Tong-Chi village who were over 16 years of age and were present in the community at the time of the earthquake were included in this population survey. Subjects were interviewed by psychiatrists using the Mini-International Neuropsychiatric Interview and questionnaires to collect demographic information and risk factors for psychiatric disorders 4 to 6 months after the earthquake. RESULTS: The prevalence rates were 9.5% for current major depression, 2.8% for past major depressive episode, and 7.9% for post-traumatic stress disorder (PTSD). Females had significantly higher rates of most psychiatric disorders. After controlling for covariates, the significant risk factors for PTSD were female gender and having sought medical service after the earthquake. Significant risk factors for major depressive episode were divorced/widowed status, education level equal to or below primary school, and prominent house damage. CONCLUSION: This population survey of earthquake disaster survivors found an increased prevalence of psychiatric disorders after exposure to a catastrophic earthquake. These results highlight the need for prompt therapeutic attention to residents of earthquake disaster areas after the event. 相似文献
46.
Frank Buntinx Richard Wachana Stefaan Bartholomeeusen Kathleen Sweldens Helena Geys 《The British journal of general practice》2005,55(511):102-107
BACKGROUND: It has been suggested that herpes zoster may be a marker for occult malignancy. AIM: To examine the emergence of a subsequent cancer diagnosis in patients with and without herpes zoster. DESIGN OF STUDY: Retrospective cohort study. SETTING: Results were based on the database of Intego, an ongoing Belgian general practice-based morbidity registry, covering 37 general practitioners and including about 311 000 patient years between the years 1994 and 2000. METHOD: Survival analysis comparing the emergence of malignancy in patients with and without herpes zoster. RESULTS: The number of patients below the age of 65 years with herpes zoster, cancer or both was too low to draw any sensible conclusions. Above the age of 65 years we identified a significant increase of cancer emergence in the whole group and in females (hazard ratio = 2.65, 95% confidence interval = 1.43 to 4.90), but not in males. No difference could be identified in the first year after the herpes zoster infection. CONCLUSION: Our results do not justify extensive testing for cancer in herpes zoster patients. The association we identified, however, leaves open a number of questions with respect to the physiopathology behind it. 相似文献
47.
M. Knappik U. Börner T. Jelinek 《European journal of clinical microbiology & infectious diseases》2005,24(10):701-703
The study presented here was conducted to evaluate the performance of the newly available RIDASCREEN Set (R-Biopharm AG, Darmstadt,
Germany) for the detection of immunoglobulin G antibodies against Entamoeba histolytica. The sensitivity and specificity of this new enzyme-linked immunosorbent assay were evaluated using a panel of sera from
239 individuals. The assay was positive for 43 of 44 patients with invasive amebiasis, including all 18 patients with amebic
liver abscess, while it was negative for 190 of 195 adult controls who were either healthy individuals or patients with other
parasitic diseases. The kit was found to be highly specific (97.4%) and sensitive (97.7%) for detecting antibodies against
E. histolytica in humans. Although antibody titers in patients with amebic liver abscess tend to be higher on average than in patients with
invasive amebiasis, it is not possible to distinguish the two forms solely based on the results of this commercial test. 相似文献
48.
The detection of antineuronal antibodies against cytoplasm and nuclei of Purkinje cells is considered to be an essential factor in the diagnosis of neurologic paraneoplastic syndromes. Published data rely on different immunological methods and relatively small numbers of patients. The clinical relevance of this phenomenon is not clear from the literature. A positive correlation between antibody detection and the appearance of neurologic paraneoplastic syndromes has been reported, but this finding has been questioned in critical reviews. 相似文献
49.
PURPOSE: Two experiments explored the extent to which induced blur, reduced luminance, and reduced visual fields affect drivers' steering performance in a driving simulator. METHODS: In experiment 1, ten young participants (M = 21.2 years) drove at approximately 89 km/h (55 mph) along a curvy roadway while being exposed to blur (0 to + 10 D), luminance (0.003 to 16.7 cd/m), and visual field (1.7 and 150 degrees) manipulations. In experiment 2, a new group of ten young participants (M = 18.5 years) drove while exposed to seven visual field sizes (1.7 to 150 degrees). RESULTS: Steering was sensitive to a reduced field size but not to the blur and luminance challenges. Acuity, on the other hand, was sensitive to the blur and luminance challenges but not to reduced field size. DISCUSSION: In healthy young drivers, steering performance is remarkably robust to severe blur and to extremely low luminances. These results support a key element of the selective degradation hypothesis advanced by Leibowitz and colleagues--that steering abilities are preserved at night even when the ability to recognize objects and hazards is not. Additional research should address the other element of this hypothesis--that drivers fail to appreciate the extent to which their visual abilities are degraded at night. 相似文献
50.
Summary A necrotizing, nonprogressive myopathy with unusual paracrystalline inclusion bodies is described in a patient who underwent long-term treatment with megadoses of vitamin E. The clinical course and morphological findings suggest a close relationship to the administration of the vitamin. The theoretical pathogenesis of muscle damage and the possible origin of paracrystalline inclusion bodies are discussed.Presented at the Jahrestagung der österreichischen Gesellschaft für Neuropathologie in Bad Ischl, on April 17, 1986This study was supported by a grant from the Deutsche Forschungsgemeinschaft (Ba 916) 相似文献