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51.
Dumas  JM; Edde  DJ 《Radiology》1986,160(2):453-456
In a prospective study conducted over a 12-month period, 30 patients underwent double-contrast arthrography of the knee followed by arthroscopic study. An 80% correlation rate was found between results. Arthrography had a higher rate of accuracy (93%) than arthroscopy (84%) and had a 7% false-positive and 0% false-negative rate. A commonly overlooked arthrographic sign--the triple-S or stuck sail sign--was 91% accurate in the prediction of meniscal tears. The complementary nature of the two examinations is discussed.  相似文献   
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1. The role of angiotensin as a modulator of proximal glomerulotubular (GT) balance was investigated in anaesthetized rats by examining the relationship between glomerular filtration rate (GFR) and absolute proximal reabsorption (APR) during removal of endogenous angiotensin II (AII) and III (AIII) with enalaprilat (CEI) and then during their subsequent replacement by intravenous infusions. 2. Enalaprilat lowered mean arterial blood pressure (MABP) and increased renal blood flow (RBF), GFR, urine flow rate and sodium excretion. Filtration fraction (FF) was not altered. Absolute proximal reabsorption, derived from fractional lithium clearance, increased by only 48% of the change expected for 'perfect' GT balance. 3. Angiotensin II replacement corrected MABP, GFR and plasma renin level, but reduced RBF and increased FF; APR was decreased and GT balance was restored. Urine flow and sodium excretion remained above control values with AII. 4. Replacement with AIII did not correct the hypotension but completely reversed the renal and renin responses to enalaprilat and restored GT balance without affecting FF. 5. It was concluded that the relation between proximal reabsorption and GFR is considerably modified by the intrarenal angiotensin concentration. The findings are best explained by a direct stimulation of proximal tubular sodium transport by angiotensin at the concentrations existing in anaesthetized rats.  相似文献   
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Patellofemoral joint: kinematic MR imaging to assess tracking abnormalities   总被引:4,自引:0,他引:4  
Shellock  FG; Mink  JH; Fox  JM 《Radiology》1988,168(2):551-553
The patellofemoral joint was imaged with magnetic resonance (MR) in the axial plane while the knee was positioned from 0 degrees to 32 degrees of flexion (nine positions). These multiple sequential images obtained within the early phases of flexion of the knee were viewed in a "cine-loop" format, producing a kinematic study that clearly demonstrated the relationship of the patella to the trochlear groove. Four healthy subjects and one patient with known bilateral subluxing patellae were studied. The preliminary results suggest that kinematic MR imaging of the patellofemoral joint is potentially useful for the evaluation of patellar tracking abnormalities.  相似文献   
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肾发育不良和肾发育不全(RAH)是先天性肾脏与尿路畸形(CAKUT)的主要表现之一,是导致儿童慢性肾脏病的重要原因。遗传因素与发病密切相关,随着全基因检测技术的发展,越来越多与RAH相关的基因突变被报道,GREB1L基因突变已被证实可导致RAH。本研究报道了1例后天性单侧肾萎缩GREB1L基因c.4688A>G杂合突变患儿,并复习相关文献。该患儿基因突变源自母亲,该变异为罕见变异,并且具有不完全外显特性,多种蛋白质危害预测软件预测该突变为有害变异。本文发现了新的GREB1L基因突变位点,可能拓展了与RAH相关的基因突变谱和临床谱。  相似文献   
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We report an instance of critical ovarian hyperstimulation syndrome in a highly responsive in-vitro fertilization patient despite the preventive measure of a 4 day 'coast' interval during which no gonadotrophins were administered while gonadotrophin-releasing hormone agonist therapy continued until serum oestradiol concentrations fell below 3000 pg/ml.   相似文献   
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BACKGROUND: Chronic obstructive pulmonary disease (COPD) is a major health problem with an estimated prevalence of 10-15% among smokers. The incidence of moderate COPD, as defined by the Global Initiative for Chronic Obstructive Lung Disease (GOLD), is largely unknown. AIM: To determine the cumulative incidence of moderate COPD (forced expiratory volume in 1 second/forced vital capacity ratio [FEV1/FVC] <0.7 and FEV1 <80% predicted) and its association with patient characteristics in a cohort of male smokers. DESIGN: Prospective cohort study. SETTING: The city of IJsselstein, a small town in the Netherlands. METHOD: Smokers aged 40-65 years who were registered with local GPs, participated in a study to identify undetected COPD. Baseline measurements were taken in 1998 of 399 smokers with normal spirometry (n = 292) or mild COPD (FEV1/FVC <0.7 and FEV1 >or=80% predicted, n = 107) and follow-up measurements were conducted in 2003. RESULTS: After a mean follow-up of 5.2 years, 33 participants developed moderate COPD (GOLD II). This showed an estimated cumulative incidence of 8.3% (95% CI = 5.8 to 11.4) and a mean annual incidence of 1.6%. No participant developed severe airflow obstruction. The risk of developing moderate COPD in smokers with baseline mild COPD (GOLD I) was five times higher than in those with baseline normal spirometry (one in five versus one in 25). CONCLUSIONS: In a cohort of middle-aged male smokers, the estimated cumulative incidence of moderate COPD (GOLD II) over 5 years was relatively high (8.3%). Age, childhood smoking, cough, and one or more GP contacts for lower respiratory tract problems were independently associated with incident moderate COPD.  相似文献   
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