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排序方式: 共有641条查询结果,搜索用时 15 毫秒
1.
2.
This is a report of a case of a serious side effect following lumbar radiculography with the water soluble contrast medium Iopamidol. The complication consisted of a generalized seizure after an episode of myoclonic jerking of the legs. This was the first complication in a series of 1070 lumbar and cervical myelograms with this medium. 相似文献
3.
Computed duplex sonography was used to examine the renal arteries in 36 hypertensive children and adolescents (ages 4–17 years) with arterial hypertension of either renal or non-renal origin. Time-averaged flow velocities, maximum blood flow velocities as well as absolute renal blood flow and renal blood flow per gram kidney weight were measured. Normal flow velocities and normal to elevated renal blood flow volume was found in patients with acute glomerulonephritis and those with signs of chronic glomerulonephritis onset. Patients having advanced stages of chronic glomerulonephritis, on the other hand, were characterized by lower levels of all parameters. Unilateral renal artery stenosis was diagnosed correctly in four patients, although one intra-renal artery stenosis escaped imaging. Scarred kidneys exhibited low-normal or reduced flow velocities and renal blood flow volumes corresponded roughly to kidney size and preservation of normal kidney structure. Hypertension in some patients with normal kidneys showed a tendency to cause higher renal blood flow without consistent acceleration of blood flow velocities. We conclude that duplex sonography is a suitable primary diagnostic tool in measuring blood flow velocities and absolute renal blood flow volume in hypertensive children, thus facilitating the choice of the next diagnostic step. 相似文献
4.
Bilateral epidermoid cysts of the testicle. 总被引:1,自引:0,他引:1
An 11-year-old boy presented with bilateral testicular masses that consisted of hyperechoic centers with hypoechoic rims on ultrasound. Surgical exploration revealed bilateral epidermoid cysts. To our knowledge this is the first reported case of bilateral epidermoid cysts in a child. Recognition of this entity requires surgical confirmation but it may obviate removal of the testicle. 相似文献
5.
Intestinal schistosomiasis japonica: CT-pathologic correlation 总被引:1,自引:0,他引:1
Lee RC; Chiang JH; Chou YH; Rubesin SE; Wu HP; Jeng WC; Hsu CC; Tiu CM; Chang T 《Radiology》1994,193(2):539
6.
The management of patients with a brain tumour is essentially dependent on the knowledge of the histology. Because of its high accuracy and low complication rate stereotactic tumour biopsy has proven to be an important diagnostic procedure, especially in deep-seated lesions. Stereotactic tumour biopsy was carried out in 18 patients with target calculation either from computerized tomography (CT) or magnetic resonance imaging (MR). 相似文献
7.
8.
Gene conversion is a likely cause of mutation in PKD1 总被引:3,自引:0,他引:3
Watnick TJ; Gandolph MA; Weber H; Neumann HP; Germino GG 《Human molecular genetics》1998,7(8):1239-1243
Approximately 70% of the gene responsible for the most common form of
autosomal dominant polycystic kidney disease ( PKD1 ) is replicated in
several highly homologous copies located more proximally on chromosome 16.
We recently have described a novel technique for mutation detection in the
duplicated region of PKD1 that circumvents the difficulties posed by these
homologs. We have used this method to identify two patients with a nearly
identical cluster of base pair substitutions in exon 23. Since pseudogenes
are known to be reservoirs for mutation via gene conversion events for a
number of other diseases, we decided to test whether these sequence
differences in PKD1 could have arisen as a result of this mechanism. Using
changes in restriction digest patterns, we were able to show that these
sequence substitutions are also present in N23HA, a rodent-human somatic
cell hybrid that contains only the PKD1 homologs. Moreover, these changes
were also detected in total DNA from several affected and unaffected
individuals that did not harbor this mutation in their PKD1 gene copy. This
is the first example of gene conversion in PKD1 , and our findings
highlight the importance of using gene-specific reagents in defining PKD1
mutations.
相似文献
9.
Toni Wendler Martin Heilemann Ronny Grunert Robert Möbius Michael Schmidt Stefan Schleifenbaum 《Journal of medical engineering & technology》2020,44(2):69-75
AbstractDiscrepancy in leg length does frequently occur as a side effect of total hip arthroplasty and may lead to reduced patient satisfaction as well as injury in the sequalae. It is consequently important to reduce leg length discrepancy where-ever technically possible. This may be achieved by recording precise intraoperative measurements and using different sized implanted components. The aim of the given study was to improve the accuracy of a previously validated optic measurement system (OMS) to reduce leg length discrepancy. This pre-existing OMS was first trialled and based on these preliminary findings developed further. Using this improved system, measurements were taken in models and cadavers. Inter observer reliability of the improved OMS was assessed. The system is introduced in the given technical feasibility study. Its accuracy was greater in the model setup (swivel joint: 772.7?±?1.5?mm; ball joint: 770.0?±?3.7?mm; reference: 772?mm) compared to the trial using cadaveric tissues (588.8?±?5.7?mm; reference: 586?mm). Results of two examiners were similar. The third one measured significantly shorter values (p=.011). The results of the measurements with the OMS indicate that a significant increase in accuracy (p?=?2.076×10?6) has been achieved compared to the previously reported system, however, a further improvement to measurement accuracy is necessary for this to be applied clinically. 相似文献
10.
Two types of phantoms were developed with which to evaluate the overall performance of digital subtraction angiography (DSA) systems. A dynamic phantom, called a "fish bone" phantom, consists of polyethylene tubes that simulate blood vessels with various lesions, such as stenoses, ulcers, and aneurysms. With this phantom, washout curves were obtained representing the relationship between iodine content and time. It will be useful for qualitative assessment of DSA images, evaluation of different image-processing schemes, and studies of blood flow analysis. A static phantom, called a "C-D" phantom, can be used for measurement of quantitative contrast-detail (C-D) diagrams and for daily monitoring of DSA systems. This was constructed of tubes of seven different diameters (2.15-0.28 mm) and 14 different concentrations of contrast medium (100%-1.1% Renografin-76 [meglumine and sodium diatrizoate]). The C-D diagrams were determined from an observer performance study using C-D phantom images obtained at four different DSA settings. 相似文献