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41.
Intrauterine spermatic cord torsion in the newborn: sonographic and pathologic correlation 总被引:2,自引:0,他引:2
In five newborn patients with spermatic cord torsion, sonography demonstrated an enlarged and globular testis, hydrocele, and skin thickening. In four of these patients the testicular parenchyma was heterogeneous. Peripheral hypoechoic areas were seen in two of the four patients; the other two had a central hypoechoic region and a peripheral echogenic rim. The testis in the fifth patient was diffusely hyperechoic. Duplex Doppler sonography performed in two patients failed to demonstrate any signal in the spermatic cord in either the abnormal or contralateral hemiscrotum. Scintigraphic findings were positive for testicular torsion in two patients and equivocal in three patients. Surgery was performed 2-12 days after sonography and established the diagnosis of spermatic cord torsion. Pathologic examination demonstrated hemorrhagic infarction of the entire testis as well as scattered calcifications. The authors conclude that a solid globular testicular mass seen during the neonatal period is suggestive of intrauterine spermatic cord torsion. 相似文献
42.
43.
Christopher Ll. Morgan Phil McEwan Paul A. Robinson Jonathan M. Plumb 《Thrombosis research》2009,124(1):37-41
Introduction
We aimed to determine the level of INR control associated with reduced stroke and mortality.Material and methods
The study used a retrospective cohort design using linked inpatient, haematology and mortality data from Cardiff and the Vale of Glamorgan, UK.Anonymised patients admitted with a diagnosis of non-valvular atrial fibrillation (NVAF) were defined as warfarin or non-warfarin treated by number of repeated International Normalised Ratio (INR) tests. Warfarin treated patients (> 5 INR tests) categorised as at moderate or high risk of stroke (CHADS2 score ≥ 2) with varying levels of INR control were compared to those who did not receive warfarin treatment using Cox proportional hazards models controlling for age, sex and CHADS2 score. Outcome measures were time to stroke and mortality.Results
6,108 patients with NVAF were identified. 2,235 (36.6%) of these patients had five or more INR readings and of these 486 (21.7%) had CHADS2 score ≥ 2. There was significant improvement in time to stroke event in those patients with INR control of greater than 70% of time in therapeutic range (2.0 to 3.0) compared with the non-warfarin treatment group. Overall survival was significantly improved for all warfarin treated groups with INR control of greater than 40% of time in range.Conclusions
Patients with INR control of above 70% of time in range had a significantly reduced risk of stroke. Patient suitability for warfarin treatment should be continuously assessed based on their ability to maintain a consistently therapeutic INR. 相似文献44.
The relationships, interactions, and association between obesity and asthma are complex, and are active sources of hypotheses
and research. An association between obesity and asthma has been reported in many studies, although considerable debate about
the existence of the association and its meaning still exists. Potential associative relationships may result from genetics,
immune system modifications, and mechanical mechanisms. The rising prevalence of asthma and obesity in children and adults,
and the significant morbidity from both, make it imperative that clinicians recognize the importance of weight management
in patients with and without asthma. 相似文献
45.
46.
Detection of circulating crosslinked fibrin derivatives by a heat extraction-SDS gradient gel electrophoretic technique 总被引:2,自引:1,他引:2
A technique has been developed to identify and quantitate unique plasmic degradation products of crosslinked fibrin in plasma. In this method, fibrin derivatives are extracted by heat precipitation and dissolved with disulfide bond reduction, after which the crosslinked gamma-gamma chain remnants are identified by SDS-polyacrylamide gradient gel electrophoresis and quantitated by densitometric analysis. A heterogenous group of gamma-gamma chains with molecular weights between 100,000 and 76,000 daltons was identified in lysates of crosslinked fibrin during plasmic degradation in vitro. Three stages of crosslinked fibrin degradation have been arbitrarily defined based primarily on the extent of degradation of these gamma-gamma polypeptide chains. As little as 20 microgram of crosslinked fibrin digests added to 1 ml of normal plasma could be detected by the heat-extraction--gel- electrophoresis technique, identifying the gamma-gamma derivatives with molecular weights of 96,000, 86,000, 82,000, and 76,000 daltons. Plasmic derivatives of gamma-gamma chains were not found in normal plasma, but they were identified in the plasma of patients with disseminated intravascular coagulation and deep-vein thrombosis, both before and in increased quantity during successful thrombolytic therapy. 相似文献
47.
Objective:
Analysis of “cine” MRI using segmental regions of interest (ROIs) has become increasingly popular for investigating bowel motility; however, variation in motility in healthy subjects both within and between scans remains poorly described.Methods:
20 healthy individuals (mean age, 28 years; 14, males) underwent MR enterography to acquire dynamic motility scans in both breath hold (BH) and free breathing (FB) on 2 occasions. Motility data were quantitatively assessed by placing four ROIs per subject in different small bowel segments and applying two measures: (1) contractions per minute (CPM) and (2) Jacobian standard deviation (SD) motility score. Within-scan (between segment) variation was assessed using intraclass correlation (ICC), and repeatability was assessed using Bland–Altman limits of agreement (BA LoA).Results:
Within-scan segmental variation: BH CPM and Jacobian SD metrics between the four segments demonstrated ICC R = 0.06, p = 0.100 and R = 0.20, p = 0.027 and in FB, the CPM and Jacobian SD metrics demonstrated ICC R = −0.26, p = 0.050 and R = 0.19, p = 0.030. Repeatability: BH CPM for matched segments ranged between 0 and 14 contractions with BA LoA of ±8.36 and Jacobian SD ranged between 0.09 and 0.51 with LoA of ±0.33. In FB data, CPM ranged between 0 and 10 contractions with BA LoA of ±7.25 and Jacobian SD ranged between 0.16 and 0.63 with LoA = ±0.28.Conclusion:
The MRI-quantified small bowel motility in normal subjects demonstrates wide intersegmental variation and relatively poor repeatability over time.Advances in knowledge:
This article presents baseline values for healthy individuals of within- and between-scan motility that are essential for understanding how this process changes in disease.Dynamic “cine” MRI acquired during MR enterography is increasingly utilized to assess bowel motility in a range of conditions, notably inflammatory bowel disease and enteric dysmotility syndromes.1–4 Analysis of the data remains primarily subjective in clinical routine, but the ability to apply quantitative techniques makes this a potentially powerful methodology to explore gastrointestinal physiology in disease as well as an emerging application as a biomarker for drug efficacy.5–7Despite the growing literature, a consensus has yet to be reached as to the best method of quantitatively analysing small bowel data and indeed a range of motility metrics are proposed.2,3,8–12 The most commonly used metric is the change in luminal diameter at a fixed anatomical position through the time series. By tracking bowel diameter, a characteristic curve can be produced with the number of contractions expressed per minute (CPM) to give an intuitive and broadly accepted metric for small bowel motility (SBM).2–4,9,11,13–15 To date, several studies have reported a relationship between CPM and dysmotility in disease, either compared with a histopathological standard or “normal” reference bowel loops.2–4,12 An array of additional metrics derived both from bowel diameter measures and more abstract processing techniques have further been implemented with varying degrees of effectiveness in disease and health.2,4,5,8,10,14,16Although intuitively attractive, the robustness of assessing overall enteric motility using only an isolated loop of bowel has received relatively little attention to date irrespective of the precise metric applied. It is unclear how representative the selected bowel loops are of overall SBM and if normal motility intrinsically differs between bowel segments, for example, between the jejunum and ileum. Furthermore, the repeatability of single loop metrics, even in normal individuals, is not well described, knowledge of which is vital if segmental analysis is to be used to diagnose, guide treatment and monitor enteric pathology.The purpose of this study is to explore segmental variation in SBM in healthy volunteers measured using two commonly reported small bowel metrics [CPM and Jacobian standard deviation (SD)] looking at (1) within-scan motility variation between different segments and (2) between-scan variation (repeatability) across two time points. 相似文献48.
Benign external genital lesions, being uncommon, can cause a significant diagnostic dilemma for the physician and anxiety for the patient. These lesions can be grouped into three categories: vascular lesions, nevi, and benign new growths. 相似文献
49.
50.
Gregory P Walcott G Neal Kay Vance J Plumb William M Smith Jack M Rogers Andrew E Epstein Raymond E Ideker 《Journal of the American College of Cardiology》2002,39(1):109-115
OBJECTIVES: This study was designed to characterize the organization of ventricular fibrillation (VF) on the endocardium of humans. BACKGROUND: Most proposed mechanisms for the maintenance of VF postulate the propagation of a number of activation wave fronts that reenter to maintain the arrhythmia. We tested the hypothesis that, in patients undergoing internal cardioverter-defibrillator implantation, VF consists primarily of a few large wave fronts on the endocardium. METHODS: Electrograms were recorded from a 36-electrode catheter in the left ventricle of 16 patients during VF. Activation times were chosen for a 2-s epoch for each fibrillation episode, and a two-dimensional Kolmogorov-Smirnov test was performed to determine if activation occurred randomly along the catheter over that time interval. The maximum cross-correlation was found for all possible pairs of electrodes on the catheter, and these values were plotted relative to the distance between the two electrodes. An exponential curve was then fit to the data, and a length constant was determined. Activation times were grouped into wave fronts along the catheter, and the lengths of the wave fronts were estimated. RESULTS: The Kolmogorov-Smirnov test showed that activation was not random along the catheter in any of the patients studied. The correlation length determined was 9 +/- 2 cm. The number of wave fronts recorded by the catheter was 9.2 +/- 2.9 wave fronts/s. The length of the pathway of each wave front along the catheter was 6.5 +/- 4.5 cm. CONCLUSIONS: Ventricular fibrillation is well organized on the endocardial surface of humans, consisting primarily of a few large wave fronts on the order of 6 to 9 cm. 相似文献