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31.
Clinical, echocardiographic, and hemodynamic characteristics of rheumatic mitral valve stenosis and atrial fibrillation 总被引:1,自引:0,他引:1
Chronic atrial fibrillation (AF) is associated with an increased frequency of embolic events and negative impact on cardiac function, and therefore, an increased morbidity and mortality risk in patients with rheumatic mitral valve stenosis (RMS). In the present study, the clinical, 2-D and Doppler echocardiographic, and left-and right-heart hemodynamic data were evaluated for 92 patients (68 women) with RMS and AF and compared with data from 118 patients (88 women) with RMS with sinus rhythm. The clinical, echocardiographic, and hemodynamic evaluations were performed within 1 to 7 days of each other. Patients with AF were older (45.7+/-13.4 vs 38.6+/-12.0 years, p < 0.01) and had a longer symptomatic period (108.2+/-117.9 vs 50.6+/-53.1 months, p < 0.01) compared with those with sinus rhythm. Most of the patients with AF were in NYHA functional capacity 3-4 (74% vs 19%), whereas most of the patients with sinus rhythm were in NYHA functional capacity 2. Patients with AF had a higher mitral valve score based on morphologic features ranging from 4 to 16 depending on the severity of disease (8.3+/-2.1 vs 6.5+/-1.9, p < 0.01) and greater left ventricular end-diastolic diameter (LVEDD) (52.3+/-8.7 vs 47.7+/-8.7 mm, p < 0.02), and end-systolic diameter (LVESD) (34.4+/-7.5 vs 30.9+/-7.5 mm, p < 0.01). Organic tricuspid valve involvement was diagnosed more frequently in patients with AF (61% vs 32%, p < 0.01). Mild mitral regurgitation was also more frequent in patients with AF (71%vs 51%, p < 0.03). The mitral valve area was similar in patients with and without AF (1.30+/-0.39 vs 1.39+/-0.41 cm2, p > 0.05). Mean diastolic mitral valve gradient and pulmonary artery pressure did not differ in patients with and without AF. Right atrial pressures were higher in patients with AF (7.6+/-3.3 vs 6.3+/-1.9 mm Hg, p < 0.02). The authors suggest that (1) AF occurred in older patients, who had a longer disease process and more serious symptoms; (2) hemodynamic derangements (mitral valve gradient, pulmonary artery pressure) did not differ in patients with and without AF; (3) greater mitral valve score, more tricuspid valve involvement, higher LVEDD, which are suggestive of greater rheumatic activity process were more frequently seen in patients with AF than in those without AF. These findings support the opinion that AF is a marker of widespread rheumatic damage in patients with RMS. 相似文献
32.
Yasar Kucukardali Oral Oncul Saban Cavuslu Mehmet Danaci Semra Calangu Hakan Erdem Ayse Willke Topcu Zuhal Adibelli Murat Akova Emel Azak Karaali Ahmet Melih Ozel Zahit Bolaman Bulent Caka Birsen Cetin Erkan Coban Oguz Karabay Cagla Karakoc Mehmet Akif Karan Selda Korkmaz Gulsen Ozkaya Sahin Alaaddin Pahsa Fatma Sirmatel Emrullah Solmazgul Namik Ozmen Ilyas Tokatli Cengiz Uzun Gulsen Yakupoglu Bulent Ahmet Besirbellioglu Hanefi Cem Gul 《International journal of infectious diseases》2008,12(1):71-79
OBJECTIVE: The purpose of this trial was to determine the spectrum of diseases with fever of unknown origin (FUO) in Turkey. METHODS: A prospective multicenter study of 154 patients with FUO in twelve Turkish tertiary-care hospitals was conducted. RESULTS: The mean age of the patients was 42+/-17 years (range 17-75). Fifty-three (34.4%) had infectious diseases (ID), 47 (30.5%) had non-infectious inflammatory diseases (NIID), 22 (14.3%) had malignant diseases (MD), and eight (5.2%) had miscellaneous diseases (Mi). In 24 (15.6%) of the cases, the reason for high fever could not be determined despite intensive efforts. The most common ID etiologies were tuberculosis (13.6%) and cytomegalovirus (CMV) infection (3.2%). Adult Still's disease was the most common NIID (13.6%) and hematological malignancy was the most common MD (7.8%). In patients with NIID, the mean duration of reaching a definite diagnosis (37+/-23 days) was significantly longer compared to the patients with ID (25+/-12 days) (p=0.007). In patients with MD, the mean duration of fever (51+/-35 days) was longer compared to patients with ID (37+/-38 days) (p=0.052). CONCLUSIONS: Although infection remains the most common cause of FUO, with the highest percentage for tuberculosis, non-infectious etiologies seem to have increased when compared with previous studies. 相似文献
33.
Nevin Karakus Serbulent Yigit Gulsum Semiha Kurt Betul Cevik Osman Demir Omer Ates 《Human immunology》2013
Objective
Genetic risk factors are known to contribute to the etiology of multiple sclerosis (MS). Interleukin (IL)-4 gene polymorphisms have been associated with immune-mediated diseases. The aim of this study was to explore the frequency of IL-4 gene intron 3 VNTR (variable number tandem repeat) polymorphism in a cohort of Turkish patients with MS.Methods
The study included 125 patients with MS and 160 healthy controls. Genomic DNA was isolated and genotyped using polymerase chain reaction (PCR) analyses for the IL-4 gene intron 3 VNTR polymorphism.Results
The distribution of genotype and allele frequencies of IL-4 gene intron 3 VNTR polymorphism was statistically different between MS patients and control group (p = 0.003 and p = 0.002, respectively). There were no statistically significant association between IL-4 VNTR polymorphism and clinical and demographical characteristics of MS patients.Conclusion
The results of this study suggest that intron 3 VNTR polymorphism of the IL-4 gene was positively associated with predisposition to develop MS in Turkish population. 相似文献34.
Ozgur Ates Chia-ho Hua Li Zhao Nadav Shapira Yoad Yagil Thomas E Merchant Matthew Krasin 《The British journal of radiology》2021,94(1118)
Objectives:When iodinated contrast is administered during CT simulation, standard practice requires a separate non-contrast CT for dose calculation. The objective of this study is to validate our hypothesis that since iodine affects Hounsfield units (HUs) more than electron density (ED), the information from post-contrast dual-layer CT (DLCT) would be sufficient for accurate dose calculation for both photon and proton therapy.Methods and materials:10 pediatric patients with abdominal tumors underwent DLCT scans before and after iodinated contrast administration for radiotherapy planning. Dose distributions with these DLCT-based methods were compared to those with conventional calibration-curve methods that map HU images to ED and stopping-power ratio (SPR) images.Results:For photon plans, conventional and DLCT approaches based on post-contrast scans underestimated the PTV D99 by 0.87 ± 0.70% (p = 0.18) and 0.36 ± 0.31% (p = 0.34), respectively, comparing to their non-contrast optimization plans. Renal iodine concentration was weakly associated with D99 deviation for both conventional (R2 = 0.10) and DLCT (R2 = 0.02) approaches. For proton plans, the clinical target volume D99 errors were 3.67 ± 2.43% (p = 0.0001) and 0.30 ± 0.25% (p = 0.40) for conventional and DLCT approaches, respectively. The proton beam range changed noticeably with the conventional approach. Renal iodine concentration was highly associated with D99 deviation for the conventional approach (R2 = 0.83) but not for DLCT (R2 = 0.007).Conclusion:Conventional CT with iodine contrast resulted in a large dosimetric error for proton therapy, compared to true non-contrast plans, but the error was less for photon therapy. These errors can be greatly reduced in the case of the proton plans if DLCT is used, raising the possibility of using only a single post-contrast CT for radiotherapy dose calculation, thus reducing the time and imaging dose required.Advances in knowledge:This study is the first to compare directly the differences in the calculated dose distributions between pre- and post-contrast CT images generated by single-energy CT and dual-energy CT methods for photon and proton therapy. 相似文献
35.
Ulgey Melih Gorler Oguzhan Karahan Gunduz Cansu 《Odontology / the Society of the Nippon Dental University》2021,109(4):845-853
Odontology - In the last decade, demand for metal-free esthetic restorations has grown considerably due to the development of materials to fulfill the need for an esthetic prosthesis. We examined... 相似文献
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37.
The impact of donor age and sex on the nucleated cell count and CD34 count in healthy bone marrow donors
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Elif Unal Ince Talia Ileri Figen Dogu Can Ates Hasan Cakmakli Klara Dalva Aydan Ikinciogullari Zumrut Uysal Mehmet Ertem 《Pediatric transplantation》2015,19(4):385-390
BM remains an important source of stem cells. The BM characteristics change with age but the estimation of CD34 calculation of one CD34+ cell per 100 nucleated cells is used for all donors including pediatric donors in the operating room before getting the actual CD34 count. In order to see whether this formula is applicable for pediatric donors, we designed a retrospective study to see the affect of the age and sex on the BM NCC, CD34 count, and CD34/NCC ratios. Ninety‐eight BM collections from 91 related donors were evaluated retrospectively (median age: nine yr [1.5–54 yr]; M/F: 41/50). A significant negative correlation was found between the donor age and NCC (r = −0.229, p < 0.05), CD34 count (r = −0.563, p < 0.01), and CD34/NCC (r = −0.664, p < 0.01). The negative correlation for CD34 count and CD34/NCC persisted in female and male donor groups. When donors younger than 16 yr of age were compared with the older donor group, the median NCC, median CD34 count, and CD34/NCC were significantly lower in the older group (p < 0.01). Age and sex have to be taken into consideration to avoid unnecessary high‐volume collections and increased operating room time in the younger donors. 相似文献
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