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51.
BACKGROUND: The life expectancy of patients with chronic renal failure who are dependent on dialysis is very poor. This study was undertaken to determine time-related outcomes in dialysis patients requiring cardiac valve replacement. METHODS: From 1994 to 2001, 29 end-stage renal disease (ESRD) patients on hemodialysis (HD) program underwent 30 valve replacement operations: 29 received mechanical valves (97%), and one received bioprosthetic valves. The sites of valve replacement were 11 aortic (36.7%), 18 mitral (60%), and one both aortic and mitral (3.3%). Mean age was 42.46 +/- 14.26 years (range 17-75 years). Follow-up was completed in 28 patients (96.5%). RESULTS: Early postoperative mortality (in the first 30 days) was 3.4% (n = 1). The overall estimated Kaplan-Meier survival was 56.7% at 36 months, 46.7% at 60 months, and 43.3% at 96 months. HD program was discontinued for two patients after renal transplantation in the follow-up period. All patients, except the one with bioprosthesis, used warfarin sodium for anticoagulation and none of them had bleeding. One of the patients had a major cerebrovascular accident (CVA) and another one had a minor CVA at the follow-up (6.7%). CONCLUSIONS: Life quality is better and life expectancy is longer after valve replacement in ESRD patients who have valvular disease. Also, longer life expectancy increases the probability for finding donors for kidney transplantation.  相似文献   
52.
Mucociliary clearance is a key defence mechanism in human upper and lower airways. Although mucociliary activity is present in both ears of the patients, most cases of chronic otitis media are unilateral.In this study, we aim to evaluate the difference between nasal mucociliary activity of the affected and non-affected sides in patients with unilateral chronic otitis media. Both nasal transport times of 36 patients with unilateral chronic otitis media were compared statistically with each other and with the control group by independent samples t-test. The nasal mucociliary transport times of the nasal cavity at the same side as the affected ear and as the non-affected ear are significantly different, in the same patients. Our study shows that impaired or decreased nasal mucociliary activity may result in dysfunction of the eustachian tube and middle-ear ciliary activity, which plays an important role in the aetiopathogenesis of chronic otitis media.  相似文献   
53.
54.
Non-steroidal anti-inflammatory drugs (NSAIDs) are the most widely used therapeutic agents in the treatment of pain, inflammation and fever. They may also have a role in the management of cancer prevention, Alzheimer's disease and prophylaxis against cardiovascular disease. These drugs act primarily by inhibiting cyclooxygenase enzyme, which has two isoforms, cyclooxygenase-1 (COX-1) and cyclooxygenase-2 (COX-2). Selective COX-2 inhibitors provide potent anti-inflammatory and analgesic effects without the side effects of gastric and renal toxicity and inhibition of platelet function. Celecoxib is a potent COX-2 inhibitor being developed for the treatment of rheumatoid arthritis and osteoarthritis. Chemoprevention is the use of pharmacological or natural agents to prevent, suppress, interrupt or reverse the process of carcinogenesis. For this purpose, celecoxib is being used for different cancer types. The effects of NSAIDs on tumor growth remain unclear, but are most likely to be multifocal. In this article, we reviewed COX-2 selectivity, the pharmacological properties of celecoxib, the use of celecoxib for cancer prevention and the mechanisms of chemoprevention.  相似文献   
55.

Background

Noradrenergic function has been linked to posttraumatic stress disorder (PTSD) and might have a role in mediating sleep disturbances of the disorder. Our objective was to relate a peripheral manifestation of noradrenergic function, sympathetic nervous system activity as indexed by heart rate variability during sleep, to the development of PTSD in subjects with recent traumatic injuries.

Methods

Subjects who had recall of life-threatening experiences were recruited from one of two regional trauma centers. Select subjects received a polysomnographic recording within 1 month of the trauma. Digitized electrocardiogram recordings were extracted from early and late rapid-eye-movement (REM) and preceding non-REM sleep periods. Autoregression was applied to R-R interval time series to calculate the ratios of low-frequency to high-frequency spectral densities (LF/HF ratios), which index sympathetic activation. Posttraumatic stress disorder status was determined at 2 months.

Results

There was a significant state × group interaction: LF/HF ratios were higher during the REM sleep of the nine subjects who were positive for PTSD symptoms, compared with the 10 subjects who were PTSD negative.

Conclusions

Our findings are consistent with the possibility that increased noradrenergic activity during REM sleep contributes to the development of PTSD.  相似文献   
56.
There is currently substantial clinical interest in zinc (Zn) as a protective agent against radiation-related normal tissue injury. To further assess this drug's potential, the effect of Zn was studied in rats using a radiation-induced skin injury model. Sprague-Dawley rats were divided into four groups. Group 1 received neither Zn nor irradiation (control group). Group 2 received 30 Gy of gamma irradiation as a single dose to the right hind legs of the rats (RT Group). Groups 3 and 4 received the same irradiation plus 5 mg/kg/day Zn (RT+5 Zn group) or 10 mg/kg/day Zn orally (RT+10 Zn group), respectively. The rats were irradiated using a cobalt-60 teletherapy unit. Acute skin reactions were assessed every three days by two independent radiation oncology experts. At the endpoint of the study, light-microscopic findings were assessed by two independent expert pathology physicians. Clinically and histopathologically, irradiation increased dermatitis when compared with the control group (p < 0.05). The severity of radiodermatitis of the rats in the RT+5 Zn and RT+10 Zn groups was significantly lower than in the RT group (p < 0.05); radiodermatitis was seen earlier in the RT group than in the other groups (p < 0.05). Zn was found to be efficacious in preventing epidermal atrophy, dermal degeneration such as edema and collagen fiber loss, and hair follicle atrophy. The most protection for radiation dermatitis was observed in the RT+10 Zn group. It would be worthwhile studying the effects of zinc sulphate supplements in radiation-treated cancer patients, in the hope of reducing radiation-induced toxicity.  相似文献   
57.
Spinal cord injury with or without trauma has been reported in the perinatal period. The prognosis depends primarily on diagnosis of the level, extent and nature of the lesion, established by correlations between clinical, imaging and electrophysiological data. A 25-day-old boy with normal birth weight delivered at term by cesarean section was transferred to In?nü University Turgut Ozal Medical Center because of respiratory distress and brachial diplegia. A suspicious medullary lesion on cervical computerized tomography was confirmed as an intramedullary lesion extending from C3 to D1 on magnetic resonance imaging (MRI). Emergent surgery consisting of exposure of the lesion site and interlaminar direct puncture of the lesion under fluoroscopy revealed that the pathology was an intramedullary hematoma. The partial evacuation of the lesion with direct puncture, the patient's neurological improvement and close follow-up of the patient with ultrasonography, electrophysiology and MRI are discussed in the light of recent literature.  相似文献   
58.
Dorsal bony septum: a split cord malformation variant   总被引:1,自引:0,他引:1  
Split cord malformations (SCMs) are rare spinal anomalies and their classification is still a matter of debate. There is no widespread consensus on the embryological basis of this entity. The unified theory, proposed by Pang et al. [Neurosurgery 1992;31:451-480], was an attempt to explain the embryogenetic mechanism as a basic error occurring around the time when the primitive neuroenteric canal closes. We report two unusual cases of SCMs with a dorsally situated bony spur. We analyzed the radiological, clinical and surgical features of the lesions and were not able to classify these cases according to the unified theory. Further embryological studies should be conducted to elucidate the mechanisms of occurrence of these lesions, and the dorsal bony septum variant should be considered in SCM surgery.  相似文献   
59.
Leptin receptor variant in women with polycystic ovary syndrome   总被引:3,自引:0,他引:3  
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60.
Retroperitoneal schwannoma is a rare tumor that originates in the neural sheath and accounts for only a small percentage of retroperitoneal tumors. Presentation is typically varied and non-specific ranging from abdominal pain, abdominal mass or an incidental finding and the diagnosis is quite often fortuitous being confirmed by anatomopathological study afterwards. We report 3 cases of benign retroperitoneal pelvic schwannoma with varied presentations. Main symptoms were abdominal and pelvic pain whereas a patient with left parailiac mass had urinary incontinence and left lower extremity pain. Surgical exploration and complete excision of tumors were successful. The histological diagnosis of the tumors was reported as benign schwannoma. All patients are doing well and had no symptoms of motor or sensory disturbances after surgery with a mean follow up of 18 mounts.  相似文献   
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