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排序方式: 共有2818条查询结果,搜索用时 31 毫秒
31.
Relationship between peripheral and central venous pressures in different patient positions, catheter sizes, and insertion sites 总被引:2,自引:0,他引:2
Tugrul M Camci E Pembeci K Al-Darsani A Telci L 《Journal of cardiothoracic and vascular anesthesia》2004,18(4):446-450
OBJECTIVE: To investigate the relationship between peripheral and central venous pressures in different patient positions (supine, prone, lithotomy, Trendelenburg, and Fowler), different catheter diameters (18 G and 20 G), and catheterization sites (dorsal hand and forearm) during surgical procedures. DESIGN: Prospective clinical study. SETTINGS: University hospital. PARTICIPANTS: Five hundred adult patients. INTERVENTIONS: Peripheral over-the-needle intravenous catheters were placed in the dorsal hand or forearm. Central venous catheters were inserted via the internal jugular or subclavian vein after induction of anesthesia. MEASUREMENTS and MAIN RESULTS: Simultaneous measurements of central and peripheral venous pressures were made during stable conditions at random time points in surgery; 1953 paired measurements were performed. Mean central venous pressure was 11 +/- 3.7 mmHg and peripheral venous pressure was 13 +/- 4 mmHg (p = 0.0001). The overall correlation between central venous and peripheral venous pressures was found to be statistically significant (r = 0.89, r(2) = 0.8, p = 0.0001). Mean difference between peripheral and central venous pressure was 2 +/- 1.8 mmHg. Ninety-five percent limits of agreement were 5.6 to -1.6 mmHg. CONCLUSION: It has been assumed that replacing central venous pressure by peripheral venous pressure would cause problems in clinical interpretation. If the validity of this data is confirmed by further studies, the authors suggest that central venous pressure could be estimated by using regression equations to compare the 2 methods. 相似文献
32.
Hocao?lu E ?zden B? Ayd?n H 《Journal of plastic, reconstructive & aesthetic surgery》2012,65(9):e246-e249
There are many different lower eyelid reconstruction techniques defined in the literature. Almost all of the published techniques have been described on elderly patients and use upper eyelid, periorbital or facial tissues as donor sites. However, in case of a paediatric patient or a young adult who has a crease-free and scarless face, camouflage of the facial donor-site scar is usually impossible. In order to avoid possible facial donor-site scars and upper eyelid deformities, a technique which uses the temporoparietal fascia (TPF) flap as the framework of a new eyelid was used for the reconstruction of an adolescent patient's postoncologic defect. The inner side of the flap was covered with nasal septal chondromucosal graft and the external side was covered with a retroauricular full-thickness skin graft. Eighteen months of unproblematic follow-up of this overlooked usage of the versatile TPF flap indicates that our technique has proved successful in terms of good functional and cosmetic outcome that is obtained at one stage. 相似文献
33.
Ozkan Kose Mustafa Celiktas Ferhat Guler Ali Bulent Baz Emre Togrul Serdar Akalin 《Archives of orthopaedic and trauma surgery》2012,132(11):1625-1630
Background
The purpose of this study is to investigate the inter- and intraobserver reliability of Crowe and Hartofilakidis classifications in the assessment of developmental dysplasia of the hip in adult patients.Materials and methods
Two consultant orthopedic surgeons classified 141 dysplastic hips on 103 standard anterior–posterior pelvis radiographs according to the Crowe and Hartofilakidis classifications. Assessments were performed in random order by each observer on two separate occasions, at least 4?weeks apart. Kappa statistics were used to establish a relative level of agreement between observers for the two readings and between separate readings by the same observer.Results
At the first readings, interobserver reliability analysis revealed kappa coefficient of 0.71 for the Crowe classification and 0.54 for the Hartofilakidis classification. At the second reading, the kappa coefficient was 0.72 for the Crowe classification and 0.75 for the Hartofilakidis classification. Intraobserver reliability analysis revealed kappa coefficients of 0.71 for the Crowe and 0.80 for the Hartofilakidis classification for observer A, and 0.76 and 0.70 for observer B.Conclusions
In conclusion, we have found substantial inter- and intraobserver agreement for Crowe classification and substantial to moderate agreement for Hartofilakidis classification in this study. Both classification systems assess the different aspects of developmental dysplasia of hip in adults. Each system has advantages and disadvantages. We suggest using both of these classifications together to increase the accuracy. 相似文献34.
Prognostic significance of estrogen receptor expression in superficial transitional cell carcinoma of the urinary bladder 总被引:1,自引:0,他引:1
OBJECTIVES: The role of estrogens in human bladder cancer still remains to be resolved. This study was undertaken to determine the estrogen receptor (ER) expression status and to elucidate the prognostic significance of ER in superficial transitional cell carcinoma (TCC) of the human bladder. METHODS: Tumor tissue blocks which were obtained by transurethral resection (TUR) from 121 patients with superficial TCC and 30 control subjects were investigated. Median follow-up was 40 months. The expression of nuclear ER was evaluated by immunohistochemistry using avidin-biotin-peroxidase method and a monoclonal ER antibody. ER staining intensity in samples was assessed semi-quantitatively. Staining characteristics were compared with the clinico-pathological results. RESULTS: ERs were detected in 12.4% of the superficial TCC patients and in 10% of the controls (P = 0.73). No association was found between ER immuno-reactive score and patients' age, sex, tumor multiplicity or tumor size. An association between the ER staining intensity and higher tumor grade was observed (P = 0.01). Grades I, II and III tumors showed 10.6, 8.7 and 44.4% staining, respectively. Survival was not affected by ER expression. In multivariate analysis ER expression was not an independent prognostic factor. CONCLUSION: Superficial TCC of the bladder shows low ER expression and it appears that ERs do not have any direct role on the prognosis of patients with superficial TCC. 相似文献
35.
Nitric oxide (NO) has a role in the etiopathogenesis of hypertension. Relaxation of vascular smooth muscles is failed when NO production is reduced leading to increased vascular peripheral resistance. N sup omega nitro-L-arginine methyl ester (L-NAME) is one of the inhibitors of NO production. The aim of this study was to investigate oxidant-antioxidant systems of renal tissue in rats with hypertension induced by L-NAME. Rats were divided into three groups: control group and study groups treated with 100 or 500 mg/l L-NAME in drinking water for 15 days. The activities of catalase (CAT), glutathione peroxidase (GSH-Px) and superoxide dismutase (SOD), and the levels of malondialdehyde (MDA) and NO were studied in the renal tissue after hypertension induction. Arterial blood pressure was increased in both L- NAME groups. CAT activity of 500-mg L-NAME group was higher than control. GSH-Px activity of 500-mg L-NAME group was decreased compared with 100-mg ones. NO level was lower in 500-mg L-NAME group than control. MDA levels in both L-NAME groups were decreased compared with control. In conclusion, hypertension was induced with oral L-NAME treatment. Increased CAT activity was compensated with decreased GSH-Px activity in 500-mg L-NAME group. Both study groups were protected from lipid peroxidation with NO inhibition. 相似文献
36.
Comparison of the Exposure Obtained by Endoscope and Microscope in the Extended Trans-Sphenoidal Approach 总被引:1,自引:0,他引:1 下载免费PDF全文
Objective: Trans-sphenoidal surgery is often combined with other approaches for the treatment of middle cranial base tumors. By combining a maxillotomy with trans-sphenoidal approach, significantly wider exposure to these regions is gained. However, endoscope-assisted techniques have also been used for sellar and parasellar and upper clival regions. Methods: An extended trans-sphenoidal approach was performed on 10 cadaver heads using the operating microscope and was repeated with a 0-degree endoscope. The mean horizontal and vertical distances were measured and pictured for each technique, and both distances were compared using a parametric paired Student's t-test. Results: The mean horizontal distances in the 10 specimens were 19.5 ± 1.8 mm by microscope and 27.5 ± 2.2 mm by endoscope, and the mean vertical distances were 25.8 ± 1.9 mm by the microscope and 34.5 ± 3.5 mm by the endoscope. Conclusion: The aim of this study was to quantify the amount of exposure obtained with an extended trans-sphenoidal approach and to compare both endoscopic and microscopic techniques. Using the endoscope in conjunction with the operating microscope may provide additional exposure and better access in skull base surgery. 相似文献
37.
Vahit Emre Ozden Goksel Dikmen Burak Beksac Ismail Remzi Tozun 《Journal of orthopaedic science》2017,22(3):517-523
Background
To evaluate the long-term clinical and radiological outcomes of cementless total hip arthroplasty (THA) in high riding hip dislocated patients with previous proximal femoral osteotomy.Methods
Twenty-one consecutive patients with a mean age forty-two years were treated with cementless THA Step-cut subtrochanteric femoral osteotomy was performed in all twenty-eight hips. Metal on polyethylene (MoP) and ceramic on ceramic (CoC) bearings were used in two different consecutive time periods. The mean follow-up time was twelve years. Harris hip score, limb length discrepancy, complications, union status of the osteotomy, survivorship of constructs were the criteria for evaluation.Results
The mean Harris hip score improved from 39.5 to 88.7 points. The mean limb length discrepancy in unilateral cases decreased from 54.5 mm to 12.3 mm. The mean amount of femoral shortening was 37 mm. The mean union time was 3.5 months and there were no delayed union and non-union. There were three cup and two femoral revisions due to osteolysis in patients who had MoP. There was only one femoral revision in patients who had CoC. The Kaplan Meier survivorship with an end point of any revision of the stem and the acetabular component was 94% (95% CI, 75%–98%) and 92% (95% CI, 74%–99%) at ten years respectively.Conclusions
Total hip arthroplasty with subtrochanteric step-cut femoral shortening is a successful technique to improve the hip functions and reconstruct limb length discrepancy in young patients with proximal femoral deformities. 相似文献38.
Vural E Winfield HL Shingleton AW Horn TD Shafirstein G 《Lasers in medical science》2008,23(4):349-353
The effects of various laser wavelengths and fluences on the fungal isolate, Trichophyton rubrum, were examined in vitro. Standard-size isolates of T. rubrum were irradiated by using various laser systems. Colony areas were compared for growth inhibition on days 1, 3, and 6 after
laser irradiation. Statistically significant growth inhibition of T. rubrum was detected in colonies treated with the 1,064-nm Q-switched Nd:YAG laser at 4 and 8 J/cm2 and 532-nm Q-switched Nd:YAG laser at 8 J/cm2. Q-switched Nd:YAG laser at 532- and 1,064-nm wavelengths produced significant inhibitory effect upon the fungal isolate
T. rubrum in this in vitro study. However, more in vitro and in vivo studies are necessary to investigate if lasers would have a potential
use in the treatment of fungal infections of skin and its adnexa. 相似文献
39.
40.
Emre Ka?ar ?mer Fatih Nas Cüneyt Erdo?an Bahattin Hakyemez 《Diagnostic and interventional radiology (Ankara, Turkey)》2015,21(6):476-482