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991.
Ultrasonography of rotator cuff tears: a review of 500 diagnostic studies   总被引:1,自引:0,他引:1  
Ultrasonography of the rotator cuff has been shown to be of value in diagnosing rotator cuff tears. This report summarizes our experience with our first 500 diagnostic examinations. All patients were examined in the hyperextended internal rotation view with commercially available high-resolution real-time ultrasound equipment. Patients were diagnosed as having a rotator cuff tear if a focal echogenic lesion or a defect within the rotator cuff was identified. This study confirmed the value of ultrasonography for the diagnosis of rotator cuff tears. Accuracy, sensitivity, and specificity all exceeded 90%, and correlated with surgical findings. This was better than arthrography in the same patient population. Ultrasound is an accurate noninvasive method of examining the rotator cuff for the presence of tears. We suggest that rotator cuff ultrasonography is the procedure of choice for the diagnosis of tears if adequate instrumentation is available.  相似文献   
992.
1. Intrarenal arterial infusion of hypertonic saline (HS) transiently increased and then gradually reduced renal blood flow (RBF) in anaesthetized dogs. Glomerular filtration rate (GFR) but not filtration fraction decreased at the end of the infusion. 2. In the presence of a potassium channel opener cromakalim (0.3 μg/kg per min), HS infusion failed to reduce RBF; the initial increase in RBF was maintained throughout the infusion. Since cromakalim also prevented the decrease in GFR, HS infusion lowered filtration fraction. 3. The results suggest that cromakalim inhibits both pre-and postglomerular vasoconstriction induced by HS infusion.  相似文献   
993.
报道温州地区胃癌高发区瑞安塘下的致癌危险因素的调查情况,结果表明它是由多种致癌危险因素的综合影响。作者应用内镜活检在18000例慢性胃病患者中查出癌前病变(高危人群)1132例,经3月~14年活检随访,表明胃癌前病变有一定的可逆转性;癌变率较高的是胃溃疡(GU)+不典型增生(ATP)组、GU+慢性萎缩性胃炎(CAG)组及CAG+ATP组均为4.1%;总癌变率为3.1%。早癌检出率占胃癌总数的48.6%,为门诊早癌检出率的6.8倍。此方法简单、经济实用。  相似文献   
994.
Hypersensitivity reactions occurring during barium studies of the gastrointestinal tract are rare. A case is presented with radiographically demonstrated angioedema in the stomach and small bowel accompanied by allergic rhinitis, which was apparently an allergic response to the barium sulfate suspension. The reaction was documented twice during separate challenges to the barium suspension performed several months apart.  相似文献   
995.
调查16-18岁视力正常男性325人650眼的屈光状态,眼位以及它们之间的关系。结果显示,远视者为504眼(77.54%),近视者66眼(10.15%),混合散光者2眼(0.31%).正视者78眼(12.00%),325人中,内隐斜(包括兼上隐斜)者为126人(38 77%),上隐斜者13人(4.00%),正位者14人(4.31%);经用行x列表的x^2检验法分析,屈光不正的类型与斜视的种类之间没有显著联系。  相似文献   
996.
We evaluated retrospectively the varying radiographic appearances of 15 solitary lucent epiphyseal lesions occurring in children. Imaging modalities used included plain films, conventional tomography, nuclear scintigraphy, and computed tomography. Forty percent of the lesions (6) were due to osteomyelitis. The remaining lesions included tuberculosis (1), foreign body granuloma (1), chondroblastoma (2), chondromyxoid fibroma (1), enchondroma (1), osteoid osteoma (2), and eosinophilic granuloma (1). Although the radiographic appearances of such lesions may be particularly characteristic, pathologic correlation is frequently necessary. The high incidence of osteomyelitis in our cases emphasizes its importance as a cause for a lucent epiphyseal lesion.  相似文献   
997.
Summary The debrisoquine/sparteine-type polymorphism of drug oxidation and the polymorphism for acetylation are two common inherited variations in human drug metabolism. The phenotypes for hydroxylation and acetylation can be predicted be newly developed methods based on mutation-specific amplification of DNA by the polymerase chain reaction (PCR), which also allow for identification of heterozygous carriers of one mutant allele.In the present study, the results of genotyping of 81 healthy European volunteers were compared with the phenotype obtained by the classical biochemical approach using debrisoquine and caffeine as probe drugs.Genotyping correctly predicted all 73 extensive metabolisers (EMs) and 6 out of 8 poor metabolisers (PMs) of debrisoquine. All 48 rapid acetylators and 33 of 35 slow acetylators were predicted.Overall, the DNA analysis result matched the in vivo phenotype in 97.5 % of individuals.  相似文献   
998.
Summary We report a patient with multiple angiographically occult vascular malformations in the brain and spine. Magnetic resonance imaging showed multiple lesions in brain and spine with hypointense areas on both T1 and T2-weighted images. These hypointense areas are usually secondary to hemosiderin deposits consistent with remote bleeding in the lesions. We conclude that when magnetic resonance reveals an intraspinal lesion with signal intensity characteristics consistent with a vascular malformation, an examination of the brain should be performed to rule out associated intracranial lesions. The finding of multiple lesions in the brain with identical signal intensity characteristics reinforces the diagnosis of vascular malformation.  相似文献   
999.
In human cortex and hippocampus area, [3H]5-HT (5 nM) labels 5-HT1A, 5-HT1D and 5-HT1E sites. After masking 5-HT1A receptors by 0.1 μM 8-OH-DPAT, the binding displaced by 0.1 μM 5-CT presumably represented 5-HT1D sites and the remaining binding 5-HT1E sites. In frontal cortex, 5-HT1A receptors represented the main binding in layers II and VI and a lower fraction on other layers. 5-HT1D and 5-HT1E sites, were more homogeneously distributed in layers II to VI (21–34% of specific [3H]5-HT binding). 5-HT1E sites were of similar affinities (KD close to 6–8 nM) in the cortical layers II to VI. In CA1 field of hippocampus, (pyramidal layer, stratum radiatum, molecular layer), CA2 and dentate gyrus, 5-HT1A receptors represented the major fraction, 5-HT1D sites a significant fraction and 5-HT1E a minor fraction of the specific [3H]5-HT binding. In CA3–CA4 fields, 5-HT1A receptors were less densely present, 5-HT1D sites were predominant and 5-HT1E sites represented a significant fraction (27%). The highest densities of 5-HT1E sites have been measured in subiculum, where 5-HT1A, 5-HT1D, and 5-HT1E binding sites were equally represented and in entorhinal cortex where 5-HT1E sites represented the major binding in layer III. They were also present in layers II and IV (29 and 24%) and, to a lesser extent, in layers V and VI. 5-HT1A sites were predominant in layer VI, II and V and were less abundant in other layers. 5-HT1D were homogeneously present in layers II, III, IV and were present in low amounts in other layers. No 5-HT1E were detected in choroid plexus, where [3H]5-HT was dramatically reduced by mesulergine (5-HT2C receptors). No significant displacement of [3H]5-HT by mesulergine was measured in other structures.  相似文献   
1000.
A review is presented about fagaronine, a benzophenanthridine alkaloid responsible for antitumoural activity. Plant source, extraction, biosynthesis, medicinal properties, especially antileukaemic activity, are described.  相似文献   
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