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排序方式: 共有498条查询结果,搜索用时 15 毫秒
1.
Bone scintigraphy of the hands and wrists represents an important adjunct imaging technique that complements plain film radiographic examination in the evaluation of chronic wrist pain. In this study, the effectiveness of bone scintigraphy was investigated in the evaluation of chronic wrist pain in the patients without the history of trauma and any radiological and rheumatological abnormalities. Seventy-one patients with normal conventional radiographs and unexplained wrist pain were evaluated prospectively between 1998 and 2003 in our hand surgery clinic. There was no trauma history and no specific physical examination findings in the patients. The bone scintigraphy was done in all patients. Fifty-two of the all patients had normal scintigram. Seventeen of the remaining 19 patients showed increased activity over triquetrum (5 cases), lunatum (4 cases), trapezium (4 cases), hamatum (2 cases) and psiforme (2 cases). As the additional radiological investigations like MRI and CT revealed no bony abnormalities, the results of bone scintigraphy were evaluated as chronic ligamentous injuries. Two patients had diffuse increased uptake compatible with synovitis. The evaluation of bone scintigraphy correlated with clinical findings is effective to choose the most efficient treatment method in chronic wrist pain.  相似文献   
2.
Tranilast is an antiallergic drug that interferes with proliferation and migration of vascular smooth muscle cell induced by platelet-derived growth factor (PDGF) and transforming growth factor-beta1 (TGF-beta1). We investigated the local effect of tranilast on neointimal hyperplasia using tranilast-coated prosthetic grafts. The inner sides of the thin-walled polytetrafluoroethylene (PTFE) grafts were coated with chitosan and tranilast containing chitosan solution. Wistar albino rats (32) were used in the study. Patches (1 x 2 mm) for vascular grafts were prepared. Three groups were tested: group 1 (n = 12; tranilast coated), group 2 (n = 10; adhesive-only film-layer-coated), and group 3 (n = 10; normal ePTFE patch grafts sutured to the carotid arteries of the rats). Recipient sites of the carotid arteries were excised 4 weeks after surgery. All sections were examined histologically for graft patency, thrombus formation, and neointimal thickness. Expression of PDGF, fibroblast growth factor, and TGF-beta1 on cross-sections of the neointima were evaluated by immunohistochemistry. No significant differences were found regarding mean neointimal thicknesses. PDGF and TGF-beta-1 expressions were significantly lower in group 1. Although a decrease in local effect of tranilast was observed for growth factor expressions at a drug concentration of 0.05 mg/cm(2), a significant reduction in neointimal hyperplasia was not achieved. The coating concentration of 0.05 mg/cm(2) may have been too low to produce an antiproliferative effect. Given our promising results, further studies are recommended and planned using different drug concentrations and time intervals.  相似文献   
3.
Human cells are exposed to exogenous insults and continuous production of different metabolites. These insults and unwanted metabolic products might interfere with the stability of genomic DNA. Recently, many studies have demonstrated that different psychiatric disorders show substantially high levels of oxidative DNA damage in the brain accompanied with morphological and functional alterations. It reveals that damaged genomic DNA may contribute to the pathophysiology of these mental illnesses. In this article, we review the roles of oxidative damage and reduced antioxidant ability in some vastly studied psychiatric disorders and emphasize the inclusion of treatment options involving DNA repair. In addition, while most currently used antidepressants are based on the manipulation of the neurotransmitter regulation in managing different mental abnormalities, they are able to prevent or reverse neurotoxin-induced DNA damage. Therefore, it may be plausible to target on genomic DNA alterations for psychiatric therapies, which is of pivotal importance for future antipsychiatric drug development.  相似文献   
4.
The aim of this prospective study was to determine the diagnostic value of Tc-99m MDP scintimammography (SMG) for the detection of breast cancer in patients with breast masses and to compare the results with Tc-99m MIBI scintimammography. Twenty patients, categorized as suspicious, positive or benign for breast cancer according to the mammographic findings were included in the study. Dual phase Tc-99m MIBI and Tc-99m MDP SMG were performed in the prone lateral position within 5 days of each other. Although early and late Tc-99m MIBI SMG showed equal (90.4%) sensitivity, the specificity of late Tc-99m MIBI (87.5%) was found superior to early (62.5%) imaging. The overall sensitivity and specificity of early Tc-99m MDP SMG were 71.4% and 62.5%, respectively. Although late Tc-99m MDP imaging showed 100% specificity, its sensitivity was only 23.8%. In the patients with palpable masses, both early Tc-99m MDP and Tc-99m MIBI showed equal sensitivity (100%), but the sensitivity of early Tc-99m MIBI (37.5%) was found slightly higher than Tc-99m MDP (25.0%) for nonpalpable breast lesions. The sensitivity of Tc-99m MIBI and Tc-99m MDP SMG in detecting metastatic axillary involvement was 66.6% and 50%, respectively. High sensitivity and specificity together with its low cost, easy availability and the possibility of detecting bone metastases seems to make Tc-99m MDP a contributive agent in the evaluation of breast lesions as an alternative to Tc-99m MIBI.  相似文献   
5.
BACKGROUND: There are no standard criteria for the timing of drain removal. The objective of this study was to determine whether the macroscopic appearance of chest tube drainage fluid to serosanguineous may be used as a criteria for drain removal. METHODS: 2,359 patients were assessed retrospectively and 80 randomized patients were followed prospectively who underwent cardiac surgery. In both parts of the study, patients were divided into two groups according to the timing of drain removal. Group I consisted of patients whose chest tubes were removed as soon as the macroscopic appearance of the drainage fluid turned to serosanguineous. Group II consisted of patients whose chest tubes were removed at the second postoperative day when the drainage output declined to less than 50 mL in a five-hour period. In the retrospective part, cases of hemodynamically significant pericardial effusion observed within seven days postoperatively were reviewed. In the prospective part, just before the drain removal, the fluid sample hematocrit obtained from the drain lines and patients' blood hematocrit were measured and recorded. Patients were evaluated with echocardiography for pericardial effusion. RESULTS: No statistically significant difference was detected in the frequency of hemodynamically significant pericardial effusion and incidence or amount of pericardial effusion between the two study groups. The drain hematocrit to blood hematocrit ratios before drain removal showed a significant correlation with pericardial effusion.The strength of correlation between the drain hematocrit to blood hematocrit ratios before drain removal and pericardial effusion was also studied using receiver operating characteristic curve, which suggests that a drain hematocrit to blood hematocrit ratio of < or = 0.3 is strongly predictive that pericardial effusion would be absent or mild between the fifth and seventh postoperative days. CONCLUSIONS: It is safe to remove the chest tubes as soon as the macroscopic appearance of the drainage fluid turns to serosanguineous since this practically indicates cessation of active bleeding.  相似文献   
6.
Free-radical generation and nitric oxide (NO) generation were detected in the rat bladder following acute bladder outlet obstruction (BOO), and the results were compared with those for vascular ischemia and reperfusion (I-R). Forty male Sprague Dawley rats were used. In the acute BOO plus I-R group (group 1), rats were catheterized with a 3-Fr catheter and an inflated balloon was positioned at the bladder neck. The bladder was overdistended after administration of Ringer solution and furosemide (12 mg/kg, each) for 60 min, and was then drained to allow reperfusion for 30 min. In the acute BOO plus nerve stimulation group (group 2), the pelvic nerve was stimulated in the distended bladder for 60 min (5 s every 5 min, 10 V/0.1 ms, 20 Hz). Pelvic nerve stimulation was performed in nonobstructed animals in group 3. In the I-R group (group 4), the distal aorta was occluded for 60 min followed by reperfusion for 30 min. Sham-operated animals served as the control group (group 5). At the end of the protocols, the levels of hydroxyl and superoxide radicals and NO levels were measured in the bladder tissues with luminol- and lucigenin-enhanced chemiluminescence methods. The results were compared by a one-way analysis of variance test. The levels of hydroxyl radicals were not significantly different between the study groups. In contrast, superoxide radicals and NO levels were significantly increased in both group 1 and group 4 compared with those in control animals (P < 0.05 for all comparisons). Superoxide radical generation in group 2 was comparable to the levels in group 1 (P > 0.05), whereas NO levels were substantially lower than in group 1 (P = 0.06). In summary, vascular I-R causes significant oxidative damage to the bladder. Acute BOO with overdistension of the bladder mimics the effects of true vascular I-R injury. The NO pathway has possibly a major role in I-R-induced bladder damage. Prolonged BOO may therefore significantly enhance the oxidative damage to the bladder and further accentuate the effects of generalized atherosclerotic processes in the elderly adult.  相似文献   
7.
OBJECT: The authors undertook a study to explore the topographic anatomical features seen during the anterolateral approach to cervical spine, anatomical variations, and certain landmarks related to the surgical procedure. METHODS: The study was conducted in 30 fresh cadavers. RESULTS: The common carotid artery bifurcation was mostly found at the level of C-4 (78%). The inferior belly of the omohyoid muscle was seen to cross the sternocleidomastoid muscle at the C5-6 disc level along the entire C-6 vertebral body. To reach the lower cervical region, the sacrifice of this muscle makes the procedure easier. The facial vein drained into the internal jugular vein mostly at the level of C3-4 (54%). The superior ganglion of the cervical sympathetic chain was located at the C-4 vertebra, but the location of the intermediate ganglion exhibited some variation. The vertebral artery entered the transverse foramen of C-6 in 27 cadavers (90%), the transverse foramen of C-7 in two cadavers (7%), and the transverse foramen of C-4 in one cadaver (3%). Because the inferior thyroid artery crossed the C6-7 interspace obliquely, the course of the inferior thyroid artery may complicate the procedure. The C-5 uncinate process was shortest and narrowest and had the greatest distance from the medial edge of the process to the anterior tubercle (p < 0.001). CONCLUSIONS: Understanding the qualitative anatomy of this region not only improves the safety of anterior and anterolateral cervical spine surgery but also allows adequate decompression of neural elements and resolution of the other pathological processes of this region. In this fresh cadaveric study, our goal was to improve the approach and decrease the incidence of complications.  相似文献   
8.
The purpose of this study was to assess the prevalence of female urinary incontinence (UI) and risk factors of bothersomeness and help-seeking behavior of hidden female UI in urology and obstetrics and gynecology outpatient clinics. This multicentric and cross-sectional study was conducted as a part of the Turkish Overactive Bladder Study. Female patients (n = 5,565) who were referred with complaints other than UI and overactive bladder symptoms were surveyed using the International Consultation on Incontinence Questionnaire Short Form (ICIQ-SF) with supplementation of five more questions. The crude prevalence of UI was found to be 35.7%. The prevalence of frequent and severe incontinence was 8.2 and 6.8%, respectively. The mean age of incontinent patients was significantly higher (p < 0.001). The prevalence of stress, urge, and mixed UI was 39.8, 24.8, and 28.9%, respectively. More than half (53%) of incontinent patients were not bothered by UI, and only 12% of incontinent patients had previously sought medical help for their problem. Frequency, severity, and type of UI were independent factors for predicting bothersome UI, while only bothersomeness increased help-seeking behavior. The ICIQ-SF score of 8 has been found to be the best cutoff value to delineate the bothersome UI. Although the crude prevalence of female UI was found to be high, bothersome UI was not so common. The majority of incontinent female patients did not seek medical help. Frequency, severity, and mixed type of UI were found to be the determinants of bothersome UI for which the ICIQ-SF cutoff score of 8 was obtained.  相似文献   
9.
Aim To review our long-term results of the sub-ureteric injection of calcium hydroxyapatite in the endoscopic management of vesicoureteral reflux (VUR) in children. Materials and methods A sub-ureteric injection of calcium hydroxyapatite was given to 14 children (23 ureteral units) affected by VUR grades I–V. All children were followed-up with monthly urine cultures, and a renal ultrasound was done on the postoperative 4th week, while the first voiding cysto-urethrogram (VCUG) control was performed on postoperative week 12. The children were followed-up with yearly renal ultrasound and monthly urine cultures, thereafter. Data from the patients’ charts were retrospectively analyzed regarding the outcome of the procedures. Results Mean follow-up time was 52 months (47–60 months). VUR was cured in 47.4% of cases after a single injection. After the second injection the global success rate was 52.1%. Ureteroneocystostomy was performed on seven refluxing ureters of five children unresponsive to sub-ureteric injection therapy. One patient underwent nephroureterectomy because of a non-functioning kidney secondary to ureteral obstruction due to migration of material at the 23rd month postoperatively. Conclusion Although favorable short-term success rates have been reported with the sub-ureteric injection of calcium hydroxyapatite without any side effects, our long-term results showed a low success rate, with the only reported serious morbidity.  相似文献   
10.
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