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111.
Breast cancer incidence has historically been 4-7 times higher in the United States than in Asia. A previous study by the authors in Asian-American women demonstrated a substantial increase in breast cancer risk in women who migrated from Asia to the United States, with the risk almost doubling during the first decade after migration. Increased use of oral contraceptives soon after migration to the United States could possibly explain this rapid rise in risk. In a population-based case-control study of Chinese, Filipino, and Japanese-American women, aged 20-55 years, who lived in San Francisco-Oakland, California; Los Angeles, California; and Oahu, Hawaii during 1983-1987, 597 cases (70% of those eligible) and 966 controls (75%) were interviewed. Controls were matched to cases on age, ethnicity, and area of residence. Oral contraceptive (OC) use increased with time since migration; 15.0% of Asian-born women who had been in the West <8 years, 33.4% of Asian-born women who had been in the West > or =8 years, and 49.6% of Asian women born in the West had ever used OCs. However, duration of OC use (adjusted for age, ethnicity, study area, years since migration, education, family history of breast cancer and age at first full-term birth) was not associated with increased risk of breast cancer. Moreover, neither OC use before age 25 years nor before first full-term birth was associated with increased risk. Results were unchanged when restricted to women under age 45 years or under age 40 years. After adjustment for duration of OC use, women who had been in the United States > or =8 years were still at almost twice the risk of breast cancer compared with women who had been in the United States 2-7 years. This study suggests that OC use cannot explain the elevated risk observed in Asian women who migrated to the United States > or =7 years ago.  相似文献   
112.
Two successful cases of eliminated atrial flutter and improved clinical status for Fontan patients are presented. An operation combining introduction of an extracardiac conduit for the Fontan connection, to direct all systemic venous blood away from the atrium, and atrial pathway division and cryoablation, is a useful surgical option for failing Fontan patients.  相似文献   
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A 45-year-old man with spinal injury and diabetes mellitus who complained high fever and progressive enlargement of left intrascrotal mass visited to our hospital. Preoperative ultrasonography demonstrated epididymitis and abscess formation. Left high orchiectomy was performed because testicular tumor could not be denied. Epididymis was replaces by bright yellow mass associated with abscess and adhered to testis strongly. Histopathologically, the mass diagnosed xanthogranulomatous epididymitis consisted of foamy macrophages and chronic inflammatory cells. This is the first case in Japanese medical literature.  相似文献   
114.
Nefiracetam, a nootropic agent, enhanced the slope of field excitatory postsynaptic potentials in the CA1 region of rat hippocampal slices to about 170% of basal levels, being evident still at 4-h washing-out of the drug. A similar sustained enhancement (>/=16 h after i.m. injection with nefiracetam) was observed in the population spikes recorded from the granular cell layer of the intact mouse hippocampus. Saturation of the enhancement in the synaptic strength occluded potentiation obtained with long-term potentiation (LTP) induced by high-frequency (tetanic) stimulation, and vice versa. Interestingly, the facilitatory action of nefiracetam was blocked by either the nicotinic acetylcholine (ACh) receptor antagonists, alpha-bungarotoxin and mecamylamine, or the selective protein kinase C (PKC) inhibitor, GF109203X, but in contrast, it was not affected by D-2-amino-5-phosphonovaleric acid (APV), a selective N-methyl-D-aspartate (NMDA) receptor antagonist. The results of the present study suggest that nefiracetam, whereas the action is independent of NMDA receptors, induces an 'LTP-like' facilitation of hippocampal synaptic transmission as a consequence of modulation of nicotinic ACh receptors and PKC. This may represent a likely mechanism underlying the cognition-enhancing actions of nefiracetam.  相似文献   
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We measured levels of platelet-derived microparticles (PMP), which have coagulative activity and are produced by platelet activation or physical stimulation, and CD62P/CD63-positive platelets in patients with diabetes mellitus to determine their clinical significance and effects on complications of diabetes including diabetic nephropathy. We also compared these levels before and after administration of the antiplatelet drug cilostazol. Plasma PMP and CD62P/CD63-positive platelet levels were significantly higher in patients with diabetes mellitus than normal controls. CD62P-positive platelet levels were significantly higher in patients with nephropathy than in patients without complications. After administration of cilostazol, PMP and CD62P/CD63-positive platelet levels were significantly decreased. The increases in platelet activity and its related procoagulant activity appear to account in part for the hypercoagulability observed in diabetes mellitus. Our findings suggest that activated platelets might play a role in the development of diabetic nephropathy. Furthermore, antiplatelet therapy with cilostazol for diabetic patients may be useful as antithrombin therapy including antiplatelet therapy, since it suppresses the production of intrinsic coagulants produced by platelet activation.  相似文献   
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BACKGROUND/AIMS: Eyes with epiretinal membranes (ERMs) often have alterations of retinal vessels. The authors studied perifoveal microcirculation in eyes with epiretinal membranes (ERMs) using scanning laser ophthalmoscope (SLO) fluorescein angiography. METHODS: Mean capillary blood flow velocity (CFV) was measured as an index of perifoveal microcirculation by SLO fluorescein angiography in 26 eyes with ERMs (19 eyes with idiopathic epiretinal membranes, seven eyes with epiretinal membranes after retinal detachment surgery) before and 6 months after vitreous surgery, and in 23 healthy control subjects. RESULTS: The mean CFV was significantly reduced in eyes with ERMs compared with healthy controls (p=0.012), and the postoperative mean CFV was significantly increased compared with the preoperative mean CFV (p=0.041). CONCLUSION: Significant changes of capillary blood flow velocity in the perifoveal areas were observed between normal subjects and eyes with epiretinal membranes. This indicates that eyes with ERMs show abnormal haemodynamics in the perifoveal capillaries.  相似文献   
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