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151.
To prevent platelet aggregation following percutaneous transluminal angioplasty (PTA), cyclooxygenase inhibitors such as acetylsalicylic acid (ASA) and indomethacin are recommended. However, ASA blocks both the proaggregating effects of thromboxane (TXA2) and the antiaggregating and vasodilating effects of prostacyclin (PGI2). The authors measured the contractile response of dilated canine carotid arteries in situ and in vitro using an isometric force transducer. Following PTA, contraction of the arterial wall was significantly reduced (p less than 0.01). By blocking cyclooxygenase with indomethacin (3 micrograms/ml), contraction was greatly improved (p less than 0.001). These results suggest that PTA may result in marked release of prostacyclin by the damaged arterial wall, which could account for the decreased responsiveness of the artery to exogenous norepinephrine.  相似文献   
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Colorectal hemangioma: radiologic findings   总被引:1,自引:0,他引:1  
The authors correlated radiographs with the clinical and histologic data of 12 patients with colorectal hemangioma. All patients presented with rectal bleeding, which was chronic in seven. Phleboliths were also visible in seven cases, which correlated with chronic bleeding in five. On barium studies, three masses were soft and three produced rigid narrowing. The atypical features of rigid luminal narrowing, which might mimic a carcinoma, and hypovascularity correlated with chronic bleeding or visible phleboliths, which suggest the correct diagnosis of colorectal hemangioma.  相似文献   
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Gheita  Tamer A  Sayed  Safaa  Azkalany  Gada S  Abaza  Nouran  Hammam  Nevin  Eissa  AH 《Clinical rheumatology》2018,37(3):757-763
Clinical Rheumatology - The objective of this study is to assess toll-like receptor-9 (TLR9) expression in CD3-positive T lymphocytes and CD19-positive B lymphocytes in systemic sclerosis (SSc)...  相似文献   
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On the Association Between Valproate and Polycystic Ovary Syndrome   总被引:5,自引:2,他引:3  
Summary: Recent studies by Isojärvi et al. have raised the issue of an increased incidence of polycystic ovary syndrome (PCOS) in women with epilepsy treated with valproate (VPA) and have proposed replacement with lamotrigine (LTG). Polycystic ovaries (PCO) are a common finding, with a prevalence >20% in the general population, and are easily detected by pelvic or vaginal ultrasonography, whereas PCOS is comparatively rare: few women with PCO have fully developed PCOS, which includes hirsutism, acne, obesity, hypofertility, hyperandrogenemia, and menstrual disorders. From an extensive review of the current literature, it appears that there are no reliable data on the actual prevalence of PCOS in normal women and in women with epilepsy. The pathogenesis of PCO is multifactorial, including genetic predisposition and the intervention of environmental factors, among which weight gain and hyperinsulinism with insulin resistance may play a part. The roles of central (hypothalamic/pituitary), peripheral, and local ovarian factors are still debated. PCO and PCOS appear to be more frequent in women with epilepsy, but there are no reliable data showing a greater prevalence after VPA. The recent studies by Isojärvi et al. may have been biased by the retrospective selection of patients. To date, there is no reason to contraindicate the use of VPA in women with epilepsy. However, patients should be informed about the risk of weight gain and its consequences.  相似文献   
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This randomized controlled trial investigated whether delaying human chorionic gonadotrophin hormone (hCG) administration within an IVF cycle impacts upon clinical outcomes. Participants included 125 women undergoing IVF/ICSI cycles at Leeds Centre for Reproductive Medicine. Subjects were aged 20-36 years, body mass index (BMI) 20-30?kg/m(2) with a normal FSH level (<8 IU/l). Administration of hCG took place 35-36?h prior to oocyte retrieval when there were ≥3 follicles ≥17?mm in diameter (Group A), delayed by 1 day (Group B) or 2 days (Group C). Outcomes included the number of oocytes retrieved per cycle, fertilization rate and live birth rate. On the day of oocyte retrieval, women in Groups B and C had significantly more mature follicles than Group A, although the number of oocytes retrieved did not differ (median = 12 in each group). Fertilization rates and embryo quality were comparable between groups. Pregnancies and live births per cycle were higher in Groups B and C (A = 30.8%, B = 54.1%, C = 38.7%; A = 17.9%, B = 27.0%, C = 25.8%), but did not reach statistical significance. Delaying hCG administration had no significant negative impact upon morphological quality of embryos, availability of surplus embryos for freezing or pregnancy outcomes. Postponing hCG may enable increased flexibility of cycle scheduling to avoid weekend procedures.  相似文献   
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