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41.

Introduction

The formation and collapse of vapor-filled bubbles near a mechanical heart valve is called cavitation. Microbubbles can be detected in vivo by doppler ultrasonography (USG) as HITS (high intensity transient signals) in cranial circulation. We investigated the relationship between exercise induced heart rate increase and HITS formation in cranial circulation.

Material and methods

Thirty-nine mechanical heart valve implanted (8 aortic valve replacement (AVR) + mitral valve replacement (MVR), 9 AVR, 22 MVR) patients aged 18-80 years old were included in our study. Microbubbles were counted in the left ventricular cavity via transthoracic echocardiography at rest per cardiac cycle. Afterwards transcranial Doppler USG was performed and HITS were counted in each patient''s middle cerebral artery at 5 min duration. Subsequently an exercise test according to the Bruce protocol was performed. After achieving maximal heart rate, microbubbles in the left ventricle and HITS were counted again.

Results

Microbubbles in the left ventricle and transcranial HITS increased after exercise significantly compared to resting values (15.79 ±10.91 microbubbles/beat vs. 26.51 ±18.00 microbubbles/beat, p < 0.001; 6.13 ±8.07 HITS/5 min vs. 13.15 ±15.87 HITS/5 min, p = 0.001). There was a significant correlation between microbubbles and HITS counts after peak exercise (r = 0.55, p < 0.001).

Conclusions

In our study, we found that the microbubbles were increasing as the heart rate increased and more HITS were propelled to the cerebral circulation. As previously shown, HITS can alter cognitive functions. Therefore heart rate control is essential in mechanical heart valve patients to protect neurocognitive functions.  相似文献   
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Background: 1% of breast cancers occur in men.The etiology is obscure. An elevated BMI has been postulated to be a cause. Methods: All male breast cancer patients operated from January 1990 to May 2001 were retrospectively reviewed. Relation between BMI and male breast cancer was examined. Results: 43 males underwent breast surgery for breast cancer during this period. 3 patients were excluded from the study because of other risk factors for breast cancer.The average BMI of 40 patients was 26.54 kg/m2, which is mildly above the level for normal weight. Conclusions: Excessive adipose tissue may increase risk of male breast cancer.  相似文献   
44.
This case report describes a case of a 38-year-old woman with hepatic adenomatosis. MRI revealed five hyperintense nodular liver lesions on T1-weighted images which were hypo-isointense with the liver parenchyma on T2-weighted images. Serial gadolinium-enhanced images did not reveal distinctive imaging findings. With the use of superparamagnetic iron oxide (SPIO) particles, hyperintense adenomas revealed signal loss on T1-weighted images after SPIO. Two subcapsular adenomas were resected based on MRI findings and histopathology confirmed MRI diagnosis.  相似文献   
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To date limited data exists that addresses the impact of urinary incontinence on sexual function. In the present study, we assessed sexual functions in patients with urinary incontinence and compared with healthy continent subjects by means of Female Sexual Function Index (FSFI) questionnaire. A total of 21 premenopausal incontinent women (three stress incontinence, nine overactive bladder and nine mixed incontinence) were enrolled in the study, and 18 healthy continent subjects served as controls. All subjects were asked to complete FSFI questionnaire and each FSFI domain scores including desire, arousal, lubrication, orgasm, satisfaction and pain were calculated. The mean scores in each domain were compared between the groups. Mean age of subjects with urinary incontinence and controls were 39.5+/-6.6 and 32.6+/-9.1 y, respectively. All domain scores were significantly lower in incontinent women except for pain. Among the incontinence types, no significant difference was determined in all domains of FSFI. Urinary incontinence significantly reduces sexual functions in premenopausal sexually active women.  相似文献   
48.
AIM: To examine the frequency and factors predisposing to candidiasis in the digestive tract in the early postoperative period after open heart surgery. METHODS: One hundred patients undergoing open heart surgery were enrolled in this study. Patients were divided into 2 groups in regard to Candida spp. colonization. Group A means increased Candida spp. colonization after open heart surgery (31/100). Group B indicates unchanged Candida spp. colonization after open heart surgery (69/100). Samples were obtained from both oral and anal mucosa in 3 different periods of operation: 1) preoperatively (stage 1), 2) at the end of the first hour in the intensive care unit (stage 2), 3) 24 hours after operation (stage 3). Findings were compared with both preoperative and intraoperative parameters. For fungal isolation Sabourauds dextrose agar and blood agar were used. RESULTS: In Group A (31), there was a significant relationship between the samples in stage 1 and 2 (p=0.031), and also a significance between stage 1 and 3 (p=0.048). Comparison between Candida positive and negative groups (Group A and B) did not reflect any statistical significance (p>0.05). CONCLUSIONS: Candida colonization in the alimentary canal in the early postoperative period after open heart surgery is due to individual preoperative features. However, early postoperative Candida colonization in the digestive tract is not a risk factor for sepsis unless the patient has an additional risk factor leading to prolongation of length of stay in the intensive care unit.  相似文献   
49.
A 64-year-old woman presented with a 2 week history of ptosis and medial-gaze paralysis of her left eye. Computed tomography scanning of the paranasal sinuses revealed an expansile, homogeneous lesion with no contrast enhancement in the sphenoid sinus. The mass was hyperintense on all MR sequences and there was extension of the mass to the left cavernous sinus and optic canal. Operation revealed a large mucocele. Third nerve palsy disappeared 4 weeks after operation. Because the spread of mucoceles is variable, they may cause different symptoms. Radiological evaluation, especially computed tomography and magnetic resonance imaging, are useful in diagnosis of mucoceles and help to explain the clinical symptoms by showing the spread of the lesion.  相似文献   
50.
We aimed to clarify the effects of different enteral nutrients (normal chow, complete balanced nutrition, elemental nutrition enriched with glutamine, immune-enhancing diet and fiber) on colonic anastomotic healing in the stress-free metabolic state. The study was carried out with 50 male Balb-C mice in five groups of 10 animals each. After transverse colon anastomosis, animals were fed with early enteral nutrients using normal chow (group 1), Ensure((R)) (group 2), Alitraq((R)) (group 3), Impact((R)) (group 4), and Benefiber Resource((R)) orange juice drink (group 5) for 7 days. There were no significant differences among the groups in bursting pressure (p > 0.05). There was no statistical difference in terms of hydroxyproline level among groups 1-3. The hydroxyproline levels of groups 4 and 5 were statistically higher than that of the control group (p < 0.05 for both comparisons). Under normal conditions without stress, we could not demonstrate the superior effects of early enteral feeding with specialized enteral preparations over normal diets on colonic anastomoses when the bursting pressures were compared.  相似文献   
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