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961.
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Ahmet H. Kaya MD Aykan Ulus MD Yasar Bayri MD Arif Topal MD Seda Gun MD Bedri Kandemir MD Adnan Dagcinar MD Alparslan Senel MD Omer Iyigun MD 《Surgical neurology》2009,72(3):263-265
Background
Literature consistently mentions that pregnancy and hormonal therapy probably increase the bleeding rate and seizure expression of cerebral cavernomas. Either increased hormonal activity or embryogenesis related abundant expression of some growth factors such as VEGF, bFGF, and placental growth factor during pregnancy were proposed to initiate angiogenic process and vascular proliferation in cavernomas, thereby increasing their bleeding rate and seizure expression.Methods
To reveal whether estrogen and/or progesterone have direct effect on cerebral cavernomas, their receptor expressions were studied immunohistochemically in recently excised 12 cerebral cavernomas.Results
Study showed no expression of either estrogen or progesterone receptors in cerebral cavernomas even the staining worked well in positive control tissues of infiltrative ductal carcinoma.Conclusions
Aggressive behavior of cerebral cavernomas during pregnancy is a commonly proven observation and attributed to some hormonal effects. However, this effect seems not related to effect of estrogen or progesterone on cavernoma tissue via receptor binding. 相似文献963.
Review of flow rate estimates of the Deepwater Horizon oil spill 总被引:1,自引:0,他引:1
Marcia K. McNutt Rich Camilli Timothy J. Crone George D. Guthrie Paul A. Hsieh Thomas B. Ryerson Omer Savas Frank Shaffer 《Proceedings of the National Academy of Sciences of the United States of America》2012,109(50):20260-20267
The unprecedented nature of the Deepwater Horizon oil spill required the application of research methods to estimate the rate at which oil was escaping from the well in the deep sea, its disposition after it entered the ocean, and total reservoir depletion. Here, we review what advances were made in scientific understanding of quantification of flow rates during deep sea oil well blowouts. We assess the degree to which a consensus was reached on the flow rate of the well by comparing in situ observations of the leaking well with a time-dependent flow rate model derived from pressure readings taken after the Macondo well was shut in for the well integrity test. Model simulations also proved valuable for predicting the effect of partial deployment of the blowout preventer rams on flow rate. Taken together, the scientific analyses support flow rates in the range of ∼50,000–70,000 barrels/d, perhaps modestly decreasing over the duration of the oil spill, for a total release of ∼5.0 million barrels of oil, not accounting for BP''s collection effort. By quantifying the amount of oil at different locations (wellhead, ocean surface, and atmosphere), we conclude that just over 2 million barrels of oil (after accounting for containment) and all of the released methane remained in the deep sea. By better understanding the fate of the hydrocarbons, the total discharge can be partitioned into separate components that pose threats to deep sea vs. coastal ecosystems, allowing responders in future events to scale their actions accordingly. 相似文献
964.
Alkan Cubuk Fatih Yanaral Faruk Ozgor Metin Savun Harun Ozdemir Akif Erbin Bahar Yuksel Omer Sarilar 《The Kaohsiung journal of medical sciences》2018,34(12):695-699
The effects of ureteral stent diameters on ureteral stent-related symptoms were evaluated by using Turkish-validated Ureteral Stent Related Symptoms Questionnaire (USSQ). Datas on 126 patients underwent uncomplicated flexible ureterorenoscopy and 62 patients underwent uncomplicated semirigid ureteroscopy surgery without stent insertion (group 3) were collected. Patients were randomized preoperatively in a double-blind fashion to 4.8 French (group 1) and 6 French (group 2) ureteral JJ stents groups. The first follow-up visit was done at one week after surgery for all groups. Stents were removed on the third postoperative week for stented groups. The second follow-up visit was done at one week after stent removal for group 1 and group 2, and four week after surgery for group 3. Preoperative characteristics, operation time and hospitalization times were similar in both groups. Total USSQ scores were 91.9, 103.0, 44.2 at first visit and 54.3, 58.7, 28.5 at second visit in group 1, group 2, and group 3, respectively. At both first and second visits, the group 2 had significantly higher USSQ scores than the group 1 (p = 0.01 and p < 0.001, respectively). Group 1 and 2 had higher scores than group 3 at both visits. Ureteral stents are associated with poor effects on patients’ comfort and high USSQ scores. Using 4.8 Fr JJ stents improves stent-related symptoms and decreases the USSQ score more than 6 Fr JJ stents. Therefore, if ureteral stent is to be used after URS, we recommend using 4.8 Fr stent. 相似文献
965.
Omer F Ozkan Erkam Komurcu Muhammet K Arik Ahu S Kemik Sükrü Tas Gurdal Nusran 《International wound journal》2014,11(6):718-722
We aimed to investigate the relationship between dorsal flap viability and serum fibronectin levels in carnitine‐administered rats. A total of 24 rats were equally divided into three groups and operated on. Group 1 (sham group n = 8): following surgery, no agent was given. Group 2 (control group, n = 8): following surgery, sterile saline solution at 0·9% with a dose of 100 mg/kg per day for 7 days was administered intraperitoneally. Group 3 (study group, n = 8): following surgery, carnitine with a dose of 100 mg/kg per day for 7 days was administered intraperitoneally. The flap model used was a 10 × 3 cm dorsal flap extending from the tip of the scapula to the hip joint. This was elevated, and then sutured back to its original site. At the end of postoperative day 8, the animals were anaesthetised and blood samples were collected from intracardiac space. Then, the animals were euthanised. Flap viability was then evaluated measuring the surviving area, using a transparent graph paper. Finally, excised tissue was examined histopathologically. The percentages of viable areas in groups 1, 2 and 3 were 64·68 ± 3·37%, 67·35 ± 5·82% and 75·15 ± 3·56%, respectively. The mean value of fibronectin levels in groups 1, 2 and 3 were 22·3 ± 3·5, 23·1 ± 3·5 and 31 ± 6·8 mg/dl, respectively. The results of this study demonstrated that 100 mg/kg carnitine administration led to an increase in flap viability, and increased serum fibronectin levels might have a role in this process. 相似文献
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