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71.
Extrinsic compression of the renal artery due to a fibromuscular band originating from the diaphragm was encountered in a 26-year-old patient who had systemic hypertension associated with stenosis and kinking of one of her renal arteries. After surgical decompression, the renal artery assumed a normal expansion with disappearance of hypertension. Six other cases of extrinsic compression of the renal artery have been found in the literature. Surgical treatment is mandatory in all cases because the mechanism that causes the lesion makes percutaneous transluminal angioplasty illusory.  相似文献   
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Insulin-like growth factor II (IGF-II) is a mitogen for manycell types and an important modulator of muscle growth and differentiation.IGF-II gene is prevalently expressed during prenatal developmentand its gene activity is regulated by genomic imprinting, inthat the allele inherited from the father is active and theallele inherited from the mother is inactive in most normaltissues. IGF-II expression is activated in several types ofhuman neoplasms and an alteration of IGF-II imprinting has beendescribed in Beckwith–Wiedemann syndrome and Wilms' tumour.Here we show that monoallelic expression of IGF-II gene is conservedin normal adult muscle tissue whereas two or more copies ofactive IGF-II alleles, arising by either relaxation of imprintingor duplication of the active allele, are found in 9 out of 11(82%) rhabdomyo-sarcomas retaining heterozygosity at 11p15,regardless of the histological subtype. Since IGF-II has beenindicated as an autocrine growth factor for rhabdomyosarcomacells, these findings strongly suggest that acquisition of adouble dosage of active IGF-II gene is an important step forthe initiation or progression of rhabdomyosarcoma tumorigenesis.Among different types of muscle tumors, relaxation of imprintingseems to arise prevalently in rhabdomyosarcomas, since we havedetected only one case of partial reactivation of the maternalIGF-II allele out of 7 lelomyosarcomas tested.  相似文献   
74.
The current study examined whether common indicators of suicide risk differ between adolescents engaging in non-suicidal self-injury (NSSI) who have and have not attempted suicide in an effort to enhance clinicians' ability to evaluate risk for suicide within this group. Data were collected from 540 high school students in the Midwest who completed the RADS, RFL-A, SIQ, and SHBQ as part of a larger adolescent risk project. Results suggest that adolescents engaging in NSSI who also attempt suicide can be differentiated from adolescents who only engage in NSSI on measures of suicidal ideation, reasons for living, and depression. Clinical implications of the findings are discussed.  相似文献   
75.
Ytterbium-DTPA was evaluated as a potential intravascular contrast agent. Ytterbium-DTPA was synthesized from ytterbium oxide and diethylene triamine penta-acetic acid (DTPA). CT scans of increasing concentrations of ytterbium and iodine showed that at 125 kVp, ytterbium was denser than an equal concentration of iodine. The LD50 of intravenous ytterbium-DTPA was 10 mM/kg (1.73 g ytterbium/kg) in rats. In enhanced CT scans and pulmonary angiography in dogs, ytterbium was visibly denser than iodine, and CT Hounsfield units showed greater enhancement of the aorta and inferior vena cava with ytterbium. The animals showed no sign of acute or delayed toxicity. Ytterbium-DTPA deserves further evaluation as a contrast agent for high kVp techniques.  相似文献   
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Keratodermia is an incurable genetic and regional disease located in the palmar and plantar regions. The author reports his experience with five cases of palmoplantar keratodermia that were treated by grafting onto the soles and the palms skin taken from the calves and the thighs.  相似文献   
78.
The accuracy of two-dimensional echocardiography in the detection of intracardiac masses was verified in 334 patients who underwent cardiac catheterization in our laboratory over 21 consecutive months. A complete two-dimensional echocardiographic (2DE) examination was performed a day before catheterization. The presence or absence of a mass was verified at surgery in 77 patients who successively underwent mitral or aortic valve replacement (51), left ventricular aneurysmectomy with or without myocardial revascularization (25), and resection of atrial myxoma (2). In 32 patients 2DE revealed the presence of a mass-left or right atrial thrombi in 12, left atrial myxoma in 2, left ventricular thrombi in 16, and endocardial vegetations in 2. The other 45 patients were free of intracardiac masses on 2DE. Anatomic verification at surgery revealed the presence of an intracardiac mass in 34 patients. In 30 (true positives) of these, 2DE revealed the mass as well, and in 4 (false negatives) the presence of a mass had not been identified by 2DE. In 2 patients (false positives) the predicted mass was not found at surgery. Absence of a mass was correctly predicted by 2DE in 41 patients (true negatives). Thus 2DE detected intracardiac masses with sensitivity of 88.2% and a specificity of 95.3%. We recommend that 2DE be performed in all patients prior to hemodynamic study and/or cardiac surgery to enable safer management of patients with intracardiac masses during cardiac catheterization and/or cardiac surgery.  相似文献   
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