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81.
Volumetric rendering techniques: applications for three-dimensional imaging of the hip 总被引:1,自引:0,他引:1
Fishman EK; Drebin B; Magid D; Scott WW Jr; Ney DR; Brooker AF Jr; Riley LH Jr; St. Ville JA; Zerhouni EA; Siegelman SS 《Radiology》1987,163(3):737-738
Volumetric rendering is a new approach to three-dimensional (3D) imaging that overcomes many of the drawbacks of currently available surface-rendering systems. Its application on the Pixar Imaging System in two cases of acetabular fracture was assessed to illustrate the features of the technique. The fast-computing architecture and large memory of this system allow rapid generation of a series of high-quality 3D images in each plane of rotation (x or spinal axis, z or somersaulting axis) that can be viewed as independent static images or as an animated real-time video loop. Editing to remove the normal contralateral hemipelvis enhances appreciation of acetabular abnormalities. Every pixel of computed tomographic data is preserved, allowing representation of both soft tissue and bone as translucent overlap. The presentation of data also allows detection of subtle abnormalities and features and minimizes the artifact generation common in surface-rendered images. 相似文献
82.
83.
Immunosuppressive acidic protein (IAP) was first found in the ascitic fluids of cancer patients. Its biochemical properties are significantly different from those of acidic protein in the serum of normal persons. Previous studies have indicated that the serum IAP concentration increases in most cancer patients and decreases to a normal level as such patients are cured. Therefore, it has been suggested as a useful marker for follow-up in operated cancer patients. In this study, analyses and comparisons of serum IAP concentrations have been made among 53 normal persons in Blackfoot disease endemic areas, 25 patients with diabetes, cataracts, hypertension and cardiovascular disease in Blackfoot disease endemic areas, 50 breast cancer patients, 13 colorectal cancer patients, and 18 Blackfoot disease patients. Serum IAP concentrations were found as follows: 454 +/- 138 micrograms/ml for normal subjects and 499 +/- 132 micrograms/ml for disease patients in Blackfoot disease endemic areas; 520 +/- 149 micrograms/ml for breast cancer patients; 864 +/- 341 micrograms/ml for colorectal cancer patients and 950 +/- 368 micrograms/ml for Blackfoot disease patients. Serum IAP concentrations were much higher in Blackfoot disease patients, than in normal persons in Blackfoot disease endemic areas (p less than 0.001), and as high as in colorectal cancer patients. In Blackfoot disease patients, the mean serum IAP concentration of 6 patients coming from the Blackfoot disease endemic areas was as high as 1,238 +/- 404 micrograms/ml, showing a positive rate of 100% to IAP (i.e. IAP concentration exceeds 500 micrograms/ml). We conclude that serum IAP assay of Blackfoot disease patients may be useful for prognosis and therapeutic monitoring. 相似文献
84.
Evaluation of monoclonal antifibrin antibodies by their binding to human blood clots 总被引:2,自引:0,他引:2
The primary goal of this study was to develop a method for evaluating fibrin-specific antibodies as thrombus detecting agents. The apparatus and assay conditions were chosen by testing antibody 64C5, which binds to the amino terminus of the fibrin beta chain, for its ability to bind to human blood clots. Using 125I-labeled antibody 64C5, the effects of antibody concentration, clot shape, clot mass, temperature, and flow rate were tested. Increased antibody binding was observed when antibody concentration, clot mass and temperature were increased. Under one set of conditions, six 125I-labeled monoclonal antifibrin antibodies (four specific for the beta chain, two specific for the alpha chain) were tested for their binding to retracted clots of human blood. Two radioiodinated antidigoxin antibodies were used as a control. Beta chain-specific antibody 59D8, which provided the highest level of binding to clot, bound 14-fold better than the control antidigoxin antibody. Neither alpha chain-specific antibody bound to clotted blood. To examine the in vivo relevance of the in vitro binding to clots, the uptake of antibody 64C5 was assessed for its binding to human fibrin clotted within the jugular vein of a rabbit. The correlation coefficient between in vitro and in vivo uptake as a function of clot weight was calculated to be 0.91. Thus, in vitro binding of monoclonal antifibrin antibodies to human blood clots was judged to be a realistic method for the comparison and selection of an ideal antifibrin antibody for detailed in vivo testing. 相似文献
85.
86.
The incidence of thromboembolitic events in patients undergoing transfemoral angiography was examined using indium-111 labeled platelets. Twenty-seven patients received approximately 300 muCi of autologous labeled platelets at least 3 hours before angiography and were scanned with a gamma camera immediately before and after angiography. All patients were free of clinically obvious complications in the 1-2 day period after angiography. Our results showed evidence of platelet deposition at 21 sites other than the puncture site in 12 (44%) patients. Most platelet deposition (54%) occurred along the region between the puncture site and the aortic bifurcation; 24% occurred at sites not traversed by the catheter. At the puncture site itself, there was substantial platelet uptake in 44% of patients. This study indicates the need for further work in determining the most suitable catheter material and in assessing the efficacy of other measures such as anticoagulant or antiplatelet therapy. 相似文献
87.
Cardiovascular influence of dental anxiety during local anesthesia for tooth extraction. 总被引:2,自引:0,他引:2
Fanny Liliani Liau Sang-Heng Kok Jang-Jaer Lee Ru-Cheng Kuo Chia-Rong Hwang Puo-Jen Yang Chung-Ping Lin Ying-Shiung Kuo Hao-Hueng Chang 《Oral surgery, oral medicine, oral pathology, oral radiology, and endodontics》2008,105(1):16-26
OBJECTIVE: The present study evaluated whether dental patient anxiety has an effect on the cardiovascular response to the delivery of anesthetic to achieve mandibular anesthesia. STUDY DESIGN: One hundred eighty adult patients scheduled to receive routine dental extraction under local anesthesia were enrolled in this prospective study. Anxiety was measured at 15 minutes before local anesthetic delivery using Corah's Dental Anxiety Scale (Corah's DAS). Anesthetic was delivered using a standard technique for mandibular nerve block with the same dose (2 cartridges) given to all patients. Cardiovascular response data including blood pressure, heart rate, O(2) saturation, and electrocardiographic changes were measured at 5 time points from 5 minutes before to 15 minutes after the administration of anesthetic. RESULTS: The mean anxiety scale score before administration of anesthetic was 9.3 (SD +/- 2.5) with a range from 4 to 20. Women had a significantly higher mean dental anxiety level than men (P < .05). Younger age was associated with a higher anxiety scale score. Severe preoperative anxiety (Corah's DAS >12) was associated with significantly increased heart rate during administration of anesthetic. Patients with severe anxiety also had a significantly greater increase in heart rate during anesthetic administration (P < .001). Younger age was associated with increased likelihood of high dental anxiety and associated cardiovascular response to dental anesthesia (P = .001). Pain on injection was also associated with increased heart rate during anesthetic administration. CONCLUSION: This study showed that Corah's dental anxiety scale is a useful tool for estimating the impact of anxiety on the heart rate during local anesthetic delivery to achieve mandibular block for dental extraction. Younger patients undergoing tooth extraction were more likely to have high anxiety levels, and younger patients with high anxiety were more likely to report a traumatic dental history. High anxiety, younger age, and traumatic dental history were correlated with greater increases in heart rate during the administration of local dental anesthesia. 相似文献
88.
老年大鼠松质骨骨重建的组织形态计量学研究 总被引:1,自引:0,他引:1
目的:研究老年大鼠及在促骨合成药前列腺素E2(PGE2)作用下松质骨骨重建和骨建造的形态计量学改变,探讨动物骨重建形态学新参数测量方法及其意义。方法:50只20月龄雄性Wistar大鼠随机分成5组,年龄对照组(基础组、10d和30d年龄对照组),PGE2给药组(分别10d和30d给予3mg/kg/d处理组)。用体内双荧光标记,不脱钙组织切片,粘合线(cement line)染色,骨组织形态计量学方法,测定骨重建和骨建造参数。结果:20月龄雄性大鼠胫骨近端松质骨的形成表面大多数为骨重建单位(占63.3%),少部分为骨建造单位(占26.7%);PGE2用药后骨重建单位增加1.5倍,骨建造单位增加4倍,比值倒置,成骨细胞10d时明显增多。说明PGE2通过刺激成骨细胞骨合成而介民导骨建造性骨增加和骨重建性骨量增加,并以前为主。结论:老年雄性大鼠 松质骨以骨重建活动为主,仍有骨建造活动。PGE2主要通过刺激成骨细胞骨建造而增加骨量。 相似文献
89.
I. A. NÆSS S. C. CHRISTIANSEN† P. ROMUNDSTAD‡ S. C. CANNEGIETER† F. R. ROSENDAAL†§ J. HAMMERSTRØM 《Journal of thrombosis and haemostasis》2007,5(4):692-699
Background: Estimates of the incidence of venous thrombosis (VT) vary, and data on mortality are limited. Objectives: We estimated the incidence and mortality of a first VT event in a general population. Methods: From the residents of Nord‐Trøndelag county in Norway aged 20 years and older (n = 94 194), we identified all cases with an objectively verified diagnosis of VT that occurred between 1995 and 2001. Patients and diagnosis characteristics were retrieved from medical records. Results: Seven hundred and forty patients were identified with a first diagnosis of VT during 516 405 person‐years of follow‐up. The incidence rate for all first VT events was 1.43 per 1000 person‐years [95% confidence interval (CI): 1.33–1.54], that for deep‐vein thrombosis (DVT) was 0.93 per 1000 person‐years (95% CI: 0.85–1.02), and that for pulmonary embolism (PE) was 0.50 per 1000 person‐years (95% CI: 0.44–0.56). The incidence rates increased exponentially with age, and were slightly higher in women than in men. The 30‐day case‐fatality rate was higher in patients with PE than in those with DVT [9.7% vs. 4.6%, risk ratio 2.1 (95% CI: 1.2–3.7)]; it was also higher in patients with cancer than in patients without cancer [19.1% vs. 3.6%, risk ratio 3.8 (95% CI 1.6–9.2)]. The risk of dying was highest in the first months subsequent to the VT, after which it gradually approached the mortality rate in the general population. Conclusions: This study provides estimates of incidence and mortality of a first VT event in the general population. 相似文献
90.
Sonographically guided antegrade common femoral artery access. 总被引:4,自引:0,他引:4
Kee-Min Yeow Cheng-Hong Toh Cheng-Hesion Wu Rui-Ying Lee Hung-Chang Hsieh Chi-Ting Liau Hao-Jui Li 《Journal of ultrasound in medicine》2002,21(12):1413-1416
OBJECTIVE: To evaluate the feasibility of sonographically guided antegrade common femoral artery puncture and superficial femoral artery access. METHODS: Fifty antegrade common femoral artery punctures and superficial femoral artery access procedures were performed under sonographic guidance alone in 30 consecutive patients (24 male and 6 female; mean age, 55.1 +/- 25.7 years; range, 13-85 years). The indications were (1) insertion of a vascular sheath for balloon angioplasty in 42 attempts (24 patients with lower leg ischemia) and (2) insertion of an angiographic catheter for 1-shot intra-arterial chemoinfusion therapy in 8 attempts (6 patients with distal femoral osteosarcomas). RESULTS: Technical success was achieved in 28 of 30 patients or 48 (96%) of 50 procedures (95% confidence interval, 80.39-98.32). The average procedure time +/- SD (excluding the failures) was 3 +/- 1 minutes (range, 2-6 minutes). In the 2 failures (2 [4%] of 50) in which common femoral artery punctures were accomplished, further superficial femoral artery cannulations were completed under fluoroscopic road map angiographic guidance. A small groin hematoma was noted in 1 patient. No arteriovenous fistula or pseudoaneurysm was encountered. CONCLUSIONS: Sonographically guided antegrade common femoral artery puncture and selective cannulation of the superficial femoral artery are feasible and safe. They may be used as adjunctive modalities in difficult cases of common femoral artery access. 相似文献