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121.
Purpose. To assess the accuracy of different MR sequences for the detection of articular cartilage abnormalities in rheumatoid arthritis. Design and patients. Ten metacarpophalangeal joints and 10 metatarsophalangeal joints (specimens from arthritis patients undergoing ablative joint surgery) were examined with a fat-suppressed (FS) 3D FLASH, a FS 3D FISP, a FS 2D fast spin-echo T2-weighted, and a 2D FS spin-echo T1-weighted sequence. Each cartilage lesion and each cortical lesion was graded from 0 to 4 (modified Outerbridge staging system). Subsequently, the results of each sequence were compared with the macroscopic findings and statistically tested against each other. Results. The study shows that 3D gradient-echo sequences with fat suppression were best for imaging and grading of cartilage lesions in arthritis of the small joints of the hands and feet. Using 3D techniques, all grade 2, grade 3, and grade 4 lesions of cartilage or cortical bone were detected. Conclusion. FS 3D gradient-echo techniques were best for the detection and grading of hyaline cartilage and subchondral bone lesions in rheumatoid arthritis. MRI has a great potential as an objective method of evaluating cartilage damage and bone erosions in rheumatoid arthritis.  相似文献   
122.
肝脏恶性肿瘤682例手术治疗分析   总被引:5,自引:0,他引:5  
目的 探讨影响肝脏恶性肿瘤患者手术治疗后长期生存的因素。方法 回顾性分析1989年 1月至 2 0 0 3年 1月施行外科手术治疗的 6 82例肝脏恶性肿瘤患者的临床资料。结果 小肝癌 (直径 <5cm ,n =2 96 )患者术后 3年、5年生存率分别为 (6 1 2 5± 4 4 1) %和 (5 3 84± 5 6 8) % ,巨大肝癌 (直径 >10cm ,n =14 5 )患者术后 3年、5年生存率分别为 (45 90± 6 98) %和 (30 2 1±10 2 3) % ;肿瘤单发患者 (n =4 0 3)术后 3年、5年生存率分别为 (6 1 86± 3 6 9) %和 (5 5 4 0±4 91) % ,肿瘤多发 (2个或 2个以上 )患者 (n =2 4 6 )术后 3年、5年生存率分别为 (38 31± 4 97) %和(2 8 0 1± 6 31) % ;术前肝功能Child分期为Ⅰ期的患者 (n =397)术后 3年、5年生存率分别为 (6 0 6 8± 3 6 8) %和 (5 0 99± 5 10 ) % ,Ⅱ期或Ⅱ期以上的患者 (n =2 85 )术后 3年、5年生存率则为 (43 0 1±5 33) %和 (36 39± 7 5 8) % ;行局部或一段切除的患者 (n =2 98)术后 3年、5年生存率分别为 (6 8 6 5± 4 95 ) %和 (6 5 38± 5 6 9) % ,行两段或两段以上及半肝切除的患者 (n =32 4 )术后 3年、5年生存率分别为 (49 88± 4 13) %和 (37 98± 5 70 ) %。结论 小肝癌  相似文献   
123.
Cancer after Kidney Transplantation in the United States   总被引:7,自引:0,他引:7  
Previous reports of cancer after kidney transplantation have been limited by small numbers of patients in single-center studies and incomplete ascertainment of cases in large registries. We examined rates of malignancies among first-time recipients of deceased or living donor kidney transplantations in 1995-2001 (n = 35 765) using Medicare billing claims. For most common tumors, e.g. colon, lung, prostate, stomach, esophagus, pancreas, ovary and breast, cancer rates were roughly twofold higher after kidney transplantation compared with the general population. Melanoma, leukemia, hepatobiliary tumors, cervical and vulvovaginal tumors were each approximately fivefold more common. Testicular and bladder cancers were increased approximately threefold, while kidney cancer was approximately 15-fold more common. Kaposi's sarcoma, non-Hodgkin's lymphomas, and nonmelanoma skin cancers were more than 20-fold increased than in the general population. Compared with patients on the waiting list, several tumors were more common after transplantation (p < 0.01): nonmelanoma skin cancers (2.6-fold), melanoma (2.2-fold), Kaposi's sarcoma (9.0-fold), non-Hodgkin's lymphoma (3.3-fold), cancer of the mouth (2.2-fold), and cancer of the kidney (39% higher). The rates for most malignancies are higher after kidney transplantation compared with the general population. Cancer should continue to be a major focus of prevention in kidney transplantation.  相似文献   
124.
Schwannomatosis is characterized by multiple non-intradermal schwannomas with patients often presenting with a painful mass in their extremities. In this syndrome malignant transformation of schwannomas is rare in spite of their large size at presentation. Non-invasive measures of assessing the biological behavior of plexiform neurofibromas in neurofibromatosis type 1 such as positron emission tomography (PET), CT scanning and MRI are well characterized but little information has been published on the use of PET imaging in schwannomatosis. We report a unique clinical presentation portraying the use of PET imaging in schwannomatosis. A 27-year-old woman presented with multiple, rapidly growing, large and painful schwannomas confirmed to be related to a constitutional mutation in the SMARCB1 complex. Whole body PET/MRI revealed numerous PET-avid tumors suggestive of malignant peripheral nerve sheath tumors. Surgery was performed on multiple tumors and none of them had histologic evidence of malignant transformation. Overall, PET imaging may not be a reliable predictor of malignant transformation in schwannomatosis, tempering enthusiasm for surgical interventions for tumors not producing significant clinical signs or symptoms.  相似文献   
125.
目的探讨多排螺旋CT(MSCT)对气管憩室的诊断价值。方法选取分析68例气管憩室的临床及影像学资料。结果本组68例共发现气管憩室82个,其中59例为单发,9例为多发(≥2个),单发占86.76%,多发占13.24%,多发气管憩室中5例为2个憩室,3例为3个憩室,1例为4个憩室;本组气管憩室大小不等,其中最大直径44.00 mm,最小直径1.50 mm,平均直径为26(23~35)mm。82个气管憩室形状多样,圆形或类圆形(囊腔样)为62个,气泡样10个,烧瓶样6个,凹槽样2个,三角样2个;MSCT能显示气管憩室与气管为单一细管或多个管道相通,其中2例气管憩室合并感染,本组68例中有慢性支气管炎、肺气肿或慢性支气管炎合并肺气肿的病例共为38例,占55.88%。结论MSCT可以清晰显示气管憩室与气管的通道、气管憩室的部位、数量、形状和内容物等情况,对气管憩室的诊断有重要价值。  相似文献   
126.
PurposeTo report the 5-year results from the Pivotal Multicenter Trial of Ultrasound-Guided Percutaneous Arteriovenous Fistula (pAVF) Creation for Hemodialysis Access.Materials and MethodsThe retrospective review of 107 intent-to-treat (ITT) patients from the pivotal trial provided a long-term follow-up population (LTP) of 85 patients with a median follow-up duration of 50 months (range, 12–60 months). Data evaluated in the LTP group were fistula maturation and usage, secondary procedures, and complications. The Kaplan-Meier analysis of primary patency, assisted primary patency, cumulative patency, and functional patency (time from 2-needle cannulation to abandonment) were performed for the ITT population.ResultsIn the LTP, 99% (84 of 85) of fistulae were mature, with 99% (78 of 79) of patients requiring hemodialysis using their pAVF. Sustained fistula use (2-needle cannulation at the prescribed rate, 2 of 3 sessions) was achieved in 92% (78 of 85) of patients, with 7 patients not using their pAVF because they were not on dialysis (n = 4), were on peritoneal dialysis (n = 2), and refused to use fistula (n = 1). Fistula maintenance was required in 31.8% (27 of 85) of patients and included fistula dysfunction (21.2%), thrombosis (5.9%), cannulation injury (12.9%), and arm swelling (4.7%). The number of procedures performed per patient per year to maintain function and patency was 0.32 (91 of 288) for years 2–5. The cumulative patency rates were 89.5%, 88.4%, 88.4%, 85.6%, and 82.0% for years 1, 2, 3, 4, and 5, respectively. The functional patency was 91.8% at the end of the study. There were no major complications related to pAVF during the long-term follow-up.ConclusionsPercutaneous fistulae have provided clinically effective and durable access for hemodialysis with low complications. The continued use and evaluation of pAVF are warranted.  相似文献   
127.
郭玉婷  张雪峰 《武警医学》2022,33(9):764-768
目的 探讨人工辅助生殖技术(assisted reproductive technology, ART)及自然受孕孪生早产儿临床结局。方法 收集医院2015-01至2020-12出生的孪生早产儿,共计364例(182对),根据受孕方式不同分为ART组和自然受孕组,ART组孪生156例(78对),自然受孕组孪生208例(104对)。对两组孪生早产新生儿期并发症情况进行回顾性分析,收集母孕期一般情况、并发症、孪生早产儿出生时孕周、Apgar评分、孪生体重及体重差值、出生后合并呼吸窘迫综合征(respiratory distress syndrome, RDS)、新生儿宫内感染性肺炎、新生儿低血糖症、院内感染、应用呼吸支持情况、应用中心静脉置管(PICC和(或)UVC)、Ⅲ~Ⅳ度颅内出血、动脉导管未闭(≥3.0 mm)、支气管肺发育不良(bronchopulmonary dysplasia, BPD)、早产儿视网膜病变(retinopathy of prematurity, ROP)、住院天数、应用静脉营养时间等信息,比较两组之间的差异。结果 ART组产妇年龄大于35岁为26.3%,高于自然...  相似文献   
128.
BackgroundOlder adults benefit most from engaging in higher-intensity physical activity, which is often determined using step rate thresholds. Fixed step rate thresholds that correspond to moderate (MPA) and vigorous-intensity physical activity (VPA) have been developed for heuristic activity promotion. The activPAL monitor uses step rate thresholds to determine activity intensity. Stepping thresholds may also vary based on body mass index (BMI) or aerobic fitness level in older adults. Despite the various thresholds used in the literature, it is unclear whether they produce similar outcomes.Research QuestionHow does time spent in physical activity intensities compare between different step rate thresholds in older adults?MethodsThirty-eight participants (24♀; 67 ± 4 years; BMI: 26.6 ± 4.4 kg/m2) wore an activPAL monitor 24-hr/day for up to 7-d (total: 205-d). Aerobic fitness (V̇O2max: 23 ± 8 ml/kg/min) was determined via indirect calorimetry during a maximal, graded cycling test. Time spent in each intensity category (light-physical-activity [LPA], MPA, VPA) was determined using the fixed (MPA/VPA) 100/130, 110/130, and activPAL step rate thresholds (74/212), as well as BMI-adjusted absolute (108.5 ± 2.5/134.0 ± 4.8) and BMI-adjusted relative (40%/60% V̇O2max; 111.4 ± 14.7/132.0 ± 19.0) cut-offs. Times spent in each intensity category were compared between methods.ResultsThe activPAL and 100/130 thresholds yielded less LPA and more MPA than all other methods. The activPAL had no time spent in VPA at all. The BMI-adjusted absolute and relative thresholds produced statistically equivalent time in LPA and MPA (via equivalence testing), but not VPA. No two methods yielded similar time spent in LPA, MPA, or VPA.SignificanceThe choice of step rate threshold has a major impact on physical activity intensity outcomes in older adults. Inherently, strategies that adjust for older adults’ body size and/or aerobic fitness level provide a more individualized data processing strategy than fixed thresholds that assume the same threshold for all older adults  相似文献   
129.

Context

Laser treatment of benign prostatic obstruction (BPO) has become more prevalent in recent years. Although multiple surgical approaches exist, there is confusion about laser-tissue interaction, especially in terms of physical aspects and with respect to the optimal treatment modality.

Objective

To compare available laser systems with respect to physical fundamentals and to discuss the similarities and differences among introduced laser devices.

Evidence acquisition

The paper is based on the second expert meeting on the laser treatment of BPO organised by the European Association of Urology Section of Uro-Technology. A systematic literature search was also carried out to cover the topic of laser treatment of BPO extensively.

Evidence synthesis

The principles of generation of laser radiation, laser fibre construction, the types of energy emission, and laser-tissue interaction are discussed in detail for the laser systems used in the treatment of BPO. The most relevant laser systems are compared and their physical properties discussed in depth.

Conclusions

Laser treatment of BPO is gaining widespread acceptance. Detailed knowledge of the physical principles allows the surgeon to discriminate between available laser systems and their possible pitfalls to guarantee high safety levels for the patient.  相似文献   
130.
银以金属银、硝酸银、磺胺嘧啶银等多种形式应用于烧伤及多种细菌感染的治疗。随着抗生素的发现与应用,这些银复合物的应用显著下降。近年来,纳米技术因可调节金属尺寸至纳米级,使金属的化学、物理与光学性质有了极大的改变.纳米级的金属银成为一种潜在的抗菌剂。由于抗生素耐药性的发生,纳米银的应用具有广阔前景。  相似文献   
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