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Haemangiopericytoma is a rare type of tumour which mostly develops in the soft parts. The article reports on the manifestations of one tumour each in the thigh and pelvis. The angiogram shows displacement of the major arteries, the tumour-supplying vessels penetrate into the growth by means of one or several peduncles, and intensive coloration takes place during the parenchyma phase. However, the "typical angiographic image" was seen in one of the two cases only.  相似文献   
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Archives of Sexual Behavior - We compared gender dysphoria (GD) patients and their same-sex siblings in terms of their 2D:4D ratios, which may reflect prenatal exposure to androgen, one of the...  相似文献   
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The use of stents for vascular disease has resulted in a paradigm shift with significant improvement in therapeutic outcomes. Polymer-coated drug-eluting stents (DES) have also significantly reduced the incidence of reobstruction post stenting, a disorder termed in-stent restenosis. However, the current DESs lack the capacity for adjustment of the drug dose and release kinetics to the disease status of the treated vessel. We hypothesized that these limitations can be addressed by a strategy combining magnetic targeting via a uniform field-induced magnetization effect and a biocompatible magnetic nanoparticle (MNP) formulation designed for efficient entrapment and delivery of paclitaxel (PTX). Magnetic treatment of cultured arterial smooth muscle cells with PTX-loaded MNPs caused significant cell growth inhibition, which was not observed under nonmagnetic conditions. In agreement with the results of mathematical modeling, significantly higher localization rates of locally delivered MNPs to stented arteries were achieved with uniform-field–controlled targeting compared to nonmagnetic controls in the rat carotid stenting model. The arterial tissue levels of stent-targeted MNPs remained 4- to 10-fold higher in magnetically treated animals vs. control over 5 days post delivery. The enhanced retention of MNPs at target sites due to the uniform field-induced magnetization effect resulted in a significant inhibition of in-stent restenosis with a relatively low dose of MNP-encapsulated PTX (7.5 μg PTX/stent). Thus, this study demonstrates the feasibility of site-specific drug delivery to implanted magnetizable stents by uniform field-controlled targeting of MNPs with efficacy for in-stent restenosis.  相似文献   
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BACKGROUND: There is still controversy about early and late results of sequenital use of internal thoracic artery (ITA) in coronary artery bypass (CAB) operations.METHODS: In this study, we report on a series of 430 consecutive patients who underwent CAB operations between 1986 and 1998, with the use of at least one sequential ITA graft. The patients, 379 men and 51 women had a mean age of 56.4 years (range 29-80 years). Both ITA grafts were used in 227 (52.8%) patients. A total of 1744 (mean 4.05 per patient) distal coronary anastomoses were performed: 1172 of which (mean 2.72) were arterial and 980 (mean 2.28) were sequential ITA anastomoses.RESULTS: Thirty-day mortality was 1.8% (n=8 patients). Perioperative myocardial infarction occurred in 12 patients (2.8%) and five of them (1.2%) were confined to the sequential ITA grafted area. Follow-up ranged from 1 month to 13 years (mean 63+/-37.7 months) for 372 patients (86.5%). Nine patients died during follow-up period. According to Kaplan-Meier method, 5 and 10 year survival rates were 95.6 and 93.4%, respectively. Coronary angiography was performed in 64 patients (17.2%) after a mean of 33 months. In 31 of these patients angiography was performed due to return of symptoms. Overall patency rate of sequential ITA anastomoses was 91.7% (111/121). Two patients underwent repeat CAB operations.CONCLUSION: Sequential use of ITA grafts was not associated with the increased perioperative mortality and morbidity and has the potential to improve the long-term results of CAB surgery because of excellent patency rates of sequential ITA anastomoses.  相似文献   
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Pronounced ultrastructural changes in the presynaptic terminals of central nervous tissues of rats were observed after various durations of sustained hypoxia or hypercapnic hypoxia. Two distinct types of morphological alterations were found. In the first type, the presynaptic terminal was greatly enlarged, measuring 3–10 μm in the greatest diameter. These terminals contained unusual multilamellar bodies in the form of compact lamellar whorls or loosely arranged concentric lamellae. The second type of terminal changes consisted of aggregated or clumped vesicles, often surrounded by attenuated glial processes. The first type of altered terminals occurred predominantly in the deep cerebellar nuclei, while the second type was present in all regions of the central nervous system examined.  相似文献   
7.
Deficient hypoxanthine-guanine phosphoribosyl transferase (HGPRT; EC 2.4.2.8) enzymes from erythrocytes of patients with hyperuricemia and with the Lesch-Nyhan syndrome migrate 15% faster in polyacrylamide gel disc electrophoresis than the normal enzyme. A half-sister of two males with partial deficiency, who had 34% of normal HGPRT activity in her erythrocytes, yielded profiles containing two distinct zones of activity; one corresponded to the enzyme found in normal individuals and one to the variant of her half-brothers. However, in her profile her variant enzyme showed notably greater activity than that observed in her half-brothers. This increase was due to an activation of the variant by normal enzyme. Electrophoresis of mixtures of normal enzyme with partially deficient enzymes from patients with hyperuricemia and with the Lesch-Nyhan syndrome also led to activation of deficient HGPRT variants by normal enzymes. Deficient variants were also activated by normal enzyme on filtration through Sephadex G-25. Experiments in which deficient variant enzymes were activated with purified normal enzyme labeled with (125)I indicated that deficient enzymes incorporate components of the normal enzyme. No such activation of deficient enzymes was ever obtained when mixtures of deficient and normal enzymes were put together in a test tube.  相似文献   
8.
The nmr relaxation rate results show unequivocally that there are at least two fractions of tissue water in both normal and edematous white matter which do not exchange on an nmr time scale (i.e. at times of the order of milli-seconds to fraction of a second). In conjunction with the electron microscopic determination of the extracellular volumes of normal and edematous white matter, the relaxation results can be interpreted in terms of the following model. The two slowly-exchanging water components giving rise to the non-exponential relaxation correspond to cellular and extracellular water; edema changes the relaxation rate of the extracellular component much more than that of the cellular component (the extracellular component becoming more "liquid-like" in its relaxation). Such behavior is consistent with the properties of the extracellular water being due to rapid exchange between motionally restricted water adsorbed at the surface of myelin sheaths, and relatively unrestricted, bulk water. Edema presumably increases the relative amount of the "bulk" water between the axons.  相似文献   
9.
This paper reports findings on the respiratory/phonatory subsystems from an on-going study investigating the effect of unilateral electrostimulation of the subthalamic nucleus (STN) on different speech subsystems in people with Parkinson's disease (PD). Speech recordings were made in the medication-off state at baseline, three months post surgery with stimulation-on, and with stimulation-off, in six right-handed PD patients. Subjects completed several speech tasks. Acoustic analyses of the maximally sustained vowel phonation were reported. The results were compared to the scores of the motor section of the Unified Parkinson's Disease Rating Scale (UPDRS-III) obtained under the same conditions. Results showed that stimulation-on improved UPDRS-III scores in all six subjects. While mild improvement was observed for all subjects in the Stimulation-on condition, three subjects received left-STN stimulation showed a significant decline in vocal intensity and vowel duration from their baseline indicating the speech function was very susceptible to micro lesions due to the surgical procedure itself when the surgical site was in the dominant hemisphere.  相似文献   
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