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呼吸前反馈调节、情景想象和过度通气 总被引:1,自引:0,他引:1
通过大量的科学证据 ,我们论述了代谢的负反馈调节不是呼吸调节的唯一机制。醒觉时呼吸的前反馈调节起了主导作用 ,前反馈调节可以在血气异常引起的负反馈调节之前 ,对将要发生的异常进行纠正 ,预见性地改变通气 ,而代谢的变化随后发生 ,避免了负反馈调节所具有的波动和滞后的缺点 ,使呼吸调节系统具有更大的灵活性和适应能力。在前反馈调节的形成过程中 ,经典的巴甫洛夫条件反射学说可能起了重要作用 .尤其重要的是表象作为条件刺激形成的条件反射 ,研究表象作为条件刺激如何形成呼吸的前反馈调节对揭示高通气综合征的发病机制具有重要意义… 相似文献
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Aktas Aykut Degirmenci Bumin Yilmaz Omer Kayan Mustafa Cetin Meltem Celik Orhan Unlu Nisa Orhan Hikmet Demirtas Hakan Koroglu Mert 《African health sciences》2015,15(3):925-930
ObjectiveThe aim was to compare coronary high-definition CT (HDCT) with standard-definition CT (SDCT) angiography as to radiation dose, image quality and accuracy.ResultsThe intraclass correlation coefficient (ICC) of measured vessel attenuation values in SDCT between the two radiologists was exceedingly good. The ICC was higher in HDCT. The radiation dose of HDCT was higher than that of SDCT. The mean tube current was 180 (mA) in HDCT and 147(mA) in SDCT with the same tube voltage (kVp). There was no significant difference between image quality.ConclusionHDCT has a higher radiation dose but has much more atenuation and the spatial resolution which improve measurement accuracy for imaging coronary arteries. 相似文献
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Elif Peker Fatma Zor Mehmet Emin Toprak Emre Bariş 《Journal of maxillofacial and oral surgery》2015,14(4):995-998
Introduction
Facial candidal abscess is an infection with a fungal cause which was presented in this case such a rarity. We report a rare case of facial abscess due to Candida species in a patient with unknown diabetes.Materials and Methods
The patient presented with a longstanding firm swelling which occurred 2 weeks ago and did not show any improvement of healing process in spite of surgical and medical treatments. MRI examinations were conclusive and compatible with abscess, so she underwent surgical intervention. Facial candidal abscess was the final diagnosis.Conclusions
We concluded that, in persistent abscesses, invasive candidiasis should be considered in the differential diagnosis of bacterial infections as it generally affects individuals with diabetes or general defects in the immune system, or those who use widespread antibiotics and steroids. 相似文献98.
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Onur Telli Hasmet Sarici Berat Cem Ozgur Omer Gokhan Doluoglu Mehmet Melih Sunay Selen Bozkurt Muzaffer Eroglu 《The Kaohsiung journal of medical sciences》2014,30(9):466-470
Bladder urothelial carcinoma is rare in young adults and occurs more commonly in older individuals. The aim of this study was to compare the clinical behavior, pathologic characteristics, and prognosis of urothelial carcinoma of urinary bladder in young versus older adults. A retrospective review of our records between 2007 and 2013 identified 56 patients (42 males and 14 females) with transitional cell carcinoma of the bladder who were less than 40 years old. Clinical and pathological parameters of patients who were less than 40 years of age were compared with those of a series of patients older than 40 years of age (the control group) during the same period. A survival analysis was performed using the Kaplan–Meier method and log-rank test, and Cox regression was performed to identify clinical parameters that affected the clinical outcomes. The mean age was 29.21 years (range, 5–40 years) for patients less than 40 years old and 61.66 years (range, 41–75) for those older than 40 years. The mean follow-up was 40.26 months (range, 12–65 months) for young patients and 42.57 months (range, 12–72 months) for the older patients. Young bladder cancer patients had smaller-sized tumors (less than 3 cm), less high-grade cancers, higher papillary urothelial neoplasms of low malignant potential, and low-grade tumors than patients older than 40 years. Multivariate logistic regression analysis predicted tumor recurrence in young patients with high-grade tumors [odds ratio (OR), 1.959; 95% confidence interval (CI), 1.235–2.965; p = 0.046] and tumors larger than 3 cm (OR, 1.772; 95% CI, 1.416–1.942; p = 0.032). The 5-year overall survival rate was 100% for young patients and 88.1% for older patients. No difference was observed in the recurrence-free (p = 0.321) and progression-free (p = 0.422) survival rates between the two groups. We concluded that although the clinical stage distribution, natural history, and outcomes of bladder urothelial cancer in young adults are similar to those in their older counterparts, clinicians must be aware that patients under 40 years of age presented with higher-grade and larger (>3 cm) tumors and are more likely to experience tumor recurrence. 相似文献