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991.
Roughness on tooth surfaces is reported to facilitate the reestablishment of microbial dental plaque. Hence, the main goal of dental scaling is to remove bacterial plaque and obtain smoother tooth surfaces. This study was aimed to assess the influence of tip wear of ultrasonic scaler inserts on root surface roughness at different working parameters. Twenty piezoelectric ultrasonic scaler inserts (10 worn/10 new) were selected to examine the erosion ratio (ER) on the scaler tips and to assess the influence of tip wear on root surface roughness. Erosion on the tip surfaces was evaluated under atomic force microscopy (AFM). Root samples were prepared and instrumented by new (Group I) and worn (Group II) inserts at different working parameters. Roughness change (Rc) on root surfaces after instrumentation was examined under profilometer and compared between and within the groups. Statistically significant differences were found between the mean ERs of new and worn tips (P < 0.01). The results of this study showed that tip angulation and instrument power strongly influenced the Rc values on instrumented samples (< 0.05). It was also revealed that tip wear influenced the Rc values on root surfaces especially at 45° tip angulation (< 0.05). Therefore, tip wear should also be considered as much as the other parameters to minimize the surface roughness during ultrasonic treatment.  相似文献   
992.
One of the most important adverse effects of zoledronic acid (ZA) is osteonecrosis of the jaw (ONJ). In previous literature, several risk factors have been identified in the development of ONJ. In this study, we aimed to determine the role of trastuzumab, an antiangiogenic agent, as an independent risk factor for the development of this serious side effect.Our study included 97 patients (mean age: 54 ± 10 years) with breast cancer, recorded in the archives of the Istanbul Florence Nightingale Breast Study Group, who received ZA therapy due to bone metastases between March 2006 and December 2013. We recorded the patients’ ages, weights, duration of treatment with ZA, number of ZA infusions, dental procedures, anticancer treatments (chemotherapy, aromatase inhibitor, trastuzumab), the presence of diabetes mellitus or renal dysfunction, and smoking habits.Thirteen patients (13.40%) had developed ONJ. Among the patients with ONJ, the mean time of exposure to ZA was 41 months (range: 13–82) and the mean number of ZA infusions was 38 (range: 15–56). The duration of treatment with ZA and the use of trastuzumab were observed to be 2 factors that influenced the development of ONJ (P = 0.049 and P = 0.028, respectively).The development of ONJ under ZA treatment may be associated solely with the duration of ZA treatment and the concurrent administration of trastuzumab. These findings show that patients who are administered trastuzumab for metastatic breast cancer while undergoing ZA treatment are prone to developing ONJ. Therefore, we recommend intense clinical observation to avoid this particular condition in patients receiving ZA and trastuzumab.  相似文献   
993.
Hypercalcaemia in patients with breast cancer is generally due to osteolytic metastases or to the activity of circulating tumour-derived products. Hyperparathyroidism is one of the most frequent aetiological factors in benign hypercalcaemia, but it is usually not considered in oncology patients. We present a high-risk early breast cancer case with hypercalcaemia in the 19th postoperative month of follow-up. The patient had high serum parathyroid hormone (PTH) levels, but ultrasonography was not diagnostic, and the existence of parathyroid adenoma was established by scintigraphy. Histopathological examination revealed chief cell parathyroid adenoma. The patient is still free of cancer recurrence in the 48th month of follow-up. Hyperparathyroidism should be considered as a possible cause of hypercalcaemia in breast cancer patients, and parathyroid scintigraphy is essential in the initial evaluation of the cases with increased serum calcium and PTH concentrations.  相似文献   
994.
Erdogan A  Eser I  Ozbilim G 《Surgery today》2004,34(9):772-773
Castlemans disease, defined as angiofollicular lymphoid hyperplasia, is a rare lymphoproliferative disorder, which usually occurs in the chest. The tumor is often asymptomatic, but it can cause nonspecific thoracic symptoms such as cough and dyspnea. Surgical removal is curative and malignant transformation has not been described. We report an unusual case of Castlemans disease localized in the posterior mediastinum and bordering the chest wall, and review the relevant literature.  相似文献   
995.
BACKGROUND: Elevated levels of basal and stimulated calcitonin are commonly seen in hereditary and sporadic medullary thyroid cancer (MTC) following total thyroidectomy. The cause of these high levels can be residual thyroid tissue, possibly with C-cell hyperplasia, and/or residual micro-MTC foci. MTC does not have the ability to concentrate radioactive iodine. However, radioactive iodine trapped by thyroid follicular cells may affect the neighbouring parafollicular cells. AIM: To investigate the effect of radioactive iodine treatment as adjuvant therapy to surgery in seven patients with persistent elevation of basal and stimulated calcitonin levels. METHODS: Pentagastrin testing was performed in each case immediately before surgery and at intervals of 6 months over a maximum period of 5 years (range, 44-60 months) after surgery. RESULTS: A significant decrease in basal and stimulated calcitonin levels was observed in three patients whose disease was localized to the thyroid gland at the final visit. In the remaining four patients, who initially had lymph node involvement at surgery, basal and stimulated calcitonin levels were decreased significantly in only one. At follow-up, of the three patients who showed no decrease in basal and stimulated calcitonin levels, two developed further regional lymph node and distant metastases. CONCLUSIONS: In patients with persistently elevated basal and stimulated calcitonin levels, radioactive iodine treatment may be the therapy of choice for C-cell hyperplasia and/or micro-MTC after optimal thyroid surgery, especially if the disease has not spread beyond the thyroid gland.  相似文献   
996.
997.
Aims: Some studies have found elevated alexithymia among patients with chronic pain, but the correlations between alexithymia and the severity of pain, depression, and anxiety among migraine patients are unclear. The aims of the present study were to investigate whether individuals suffering from episodic migraine (EM) differ from those with chronic migraine (CM) in regards to depression, anxiety, and alexithymia measures and to investigate the association of alexithymia with the results of depression and anxiety test inventories and illness characteristics. Methods: A total of 165 subjects with EM and 135 subjects with CM were studied. The Beck Depression Inventory (BDI), State–Trait Anxiety Inventory (STAI), and Toronto Alexithymia Scale (TAS) were administered to all subjects. The correlation between alexithymia and sociodemographic variables, family history of migraine and illness characteristics (pain severity, frequency of episode, duration of illness) were evaluated. Results: Compared with EM patients, the CM patients had significantly higher scores on measures of depression but not alexithymia and anxiety. There was a positive correlation between TAS scores and age and education in both migraine groups, but there was no correlation between TAS scores and other demographic variables. Depression and anxiety were significantly correlated with alexithymia in both migraine groups. Conclusion: Our results indicate that CM patients are considerably more depressive than EM patients. In this study, depression and anxiety were significantly correlated with alexithymia in both migraine groups. Our results demonstrate a positive association between depression, anxiety, and alexithymia in migraine patients.  相似文献   
998.
BACKGROUND: Acute aortic dissection coexisting with coronary malperfusion is a relatively rare but fatal condition. Surgical treatment of these patients is to perform early coronary revascularization concomitant with aortic repair. We review our surgical results of a selected group of 14 patients with type A acute aortic dissection and coronary artery dissection. METHODS: Between January 1993 and March 2005, 14 patients (10.2%) from a total of 136 consecutive patients with acute type A aortic dissection concomitant coronary dissection were treated by performing aortic repair and coronary artery bypass grafting. There were 11 men and 3 women (mean age, 56.7 +/- 8.4 years). The right coronary artery was involved in eight patients, the left in two patients, and both coronary arteries in four patients. At admission, nine patients had Q waves (64.2%), inferior in seven (50%) and anterior or lateral in two (14.2%). RESULTS: Hospital mortality rate was 21.4% (3 of 14 patients). Of these, two patients could not be weaned from cardiopulmonary bypass, and one patient died of multiorgan failure in the intensive care unit. CONCLUSIONS: Since acute type A aortic dissection with coronary involvement is associated with high mortality rate, immediate coronary artery bypass grafting and aortic repair is a safe and reliable approach to these challenging group of patients.  相似文献   
999.
The aim of this study was to investigate the effects of sleep deprivation induced anxiety on anaerobic performance. Thirteen volunteer male physical education students completed the Turkish version of State Anxiety Inventory and performed Wingate anaerobic test for three times: (1) following a full-night of habitual sleep (baseline measurements), (2) following 30 hours of sleep deprivation, and (3) following partial-night sleep deprivation. Baseline measurements were performed the day before total sleep deprivation. Measurements following partial sleep deprivation were made 2 weeks later than total sleep deprivation measurements. State anxiety was measured prior to each Wingate test. The mean state anxiety following total sleep deprivation was higher than the baseline measurement (44.9 ± 12.9 vs. 27.6 ± 4.2, respectively, p = 0.02) whereas anaerobic performance parameters remained unchanged. Neither anaerobic parameters nor state anxiety levels were affected by one night partial sleep deprivation. Our results suggest that 30 hours continuous wakefulness may increase anxiety level without impairing anaerobic performance, whereas one night of partial sleep deprivation was ineffective on both state anxiety and anaerobic performance.

Key points

  • Short time total sleep deprivation (30 hours) increases state anxiety without any competition stress.
  • Anaerobic performance parameters such as peak power, mean power and minimum power may not show a distinctive difference from anaerobic performance in a normal sleep day despite the high anxiety level induced by short time sleep deprivation.
  • Partial sleep deprivation does not affect anxiety level and anaerobic performance of the next day.
Key words: Psychophysiological disorders, mood, insufficient sleep, muscle fatique  相似文献   
1000.
Malignant tumors of myoepithelial origin have been increasingly recognized at a variety of sites. Herein, we describe an example of malignant myoepithelioma arising in intracranial dura. The patient is a 47-year-old woman who presented with intracranial hemorrhage and on magnetic resonance imaging was found to have an enhancing tumor. No extracranial primary tumor was identified. A gross total resection was performed. Histologically, it varied in pattern from diffuse to focally (<10%) ductular and consisted of epitheloid to spindle cells showing marked mitotic activity. Prominent infiltration of the dura was noted. Immunohistochemical stains showed convincing expression of cytokeratins (AE1/AE3 and CAM 5.2), S-100 protein, smooth muscle actin, and glial fibrillary acidic protein. Electron microscopy performed on formalin-fixed, paraffin-embedded tissue demonstrated cohesive cells with focal intermediate filament content and surface basal lamina formation at stromal interfaces. Occasional desmosomes with tonofilaments surrounded intercellular lumina containing masses of filamentous material. This example of malignant myoepithelioma is the first convincing primary salivary gland type tumor to arise in an intracranial location outside the sellar region or ear. Intracranial dura should be added to various sites at which this morphologically heterogenous tumor may arise.  相似文献   
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