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41.
Magnetic resonance imaging and spectroscopy of hepatic iron overload   总被引:2,自引:0,他引:2  
Experimental animals that had been given excess iron in their diet were studied by magnetic resonance (MR) imaging in vivo and by magnetic resonance (MR) spectroscopy in vitro. Hepatic iron overload in patients with transfusional iron excess was studied by MR imaging, and isolated iron protein fractions were studied in vitro by MR spectroscopy. The spin echo image intensity of livers with iron overload was decreased because of the extreme decreases in T2 compared with normal; T1 was decreased only moderately. The relaxation rates 1/T2 and 1/T1 both showed a linear relationship to hepatic iron levels. Ferritin solutions showed moderate decreases in T2 and mild decreases in T1. The T2 relaxivity of ferritin, which is due to the iron core rather than the apoferritin protein shell, does not appear sufficient to account for the extreme decrease in T2 observed in hepatic iron overload. Low molecular weight cytosol iron is present in lower concentrations than ferritin but potentially has much greater relaxivity and may contribute to the MR findings. These techniques may be useful in other studies of iron metabolism.  相似文献   
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Evaluation of abdominal trauma by computed tomography   总被引:11,自引:2,他引:9  
Federle  MP; Goldberg  HI; Kaiser  JA; Moss  AA; Jeffrey  RB  Jr; Mall  JC 《Radiology》1981,138(3):637-644
Computed tomography (CT) was used in the evaluation of 100 patients suffering abdominal trauma. The type of trauma was blunt in 78 patients, penetrating in eight, and iatrogenic in 14. Forty per cent of cases had normal CT scans, while 60% showed substantial abdominal or retroperitoneal injuries. Surgery, clinical follow-up, and repeated radiologic examinations confirmed the accuracy of CT, and there were no cases in which medical or surgical management was inappropriately guided by CT. A wide variety of injuries was detected, including 19 splenic, eight hepatic, six pancreatic, 13 renal, 13 retroperitoneal or abdominal wall, and one intraperitoneal. CT has major advantages over plain radiography, radionuclide imaging, and angiography in assessment of trauma-induced injuries.  相似文献   
45.
Intracerebral venous angioma is a rare congenital vascular malformation of the brain. Three cases are reported, all of which had strikingly similar angiographic findings in the venous phase, viz., a local network of small medullary veins which converge centrally into a single large venous channel which courses transcerebrally to reach the superficial venous system. No gross abnormalities are seen in the arterial phase with the usual techniques. However, magnification delineated enlarged arterial branches supplying the periphery of the malformation in 2 of the 3 cases. A poorly marginated homogeneous blush and early filling of the draining veins were also seen in these 2 patients. The findings in the venous phase agree with those described in previous isolated case reports and appear to be highly suggestive of this rare malformation.  相似文献   
46.
Ground whole rye and airborne rye dust of comparable size distribution were tested for their ability to activate the complement cascade via the alternative pathway. Precipitin-negative pooled normal human serum was incubated with increasing amounts of the two rye dusts. Electrophoresis of the resultant supernatant fluids demonstrated the conversion of the proactivator of the third component of complement to the gamma-migrating activator of the third component. This activation was completely prevented by pre-treating the serum with the chelator EDTA, while pre-treatment with EGTA allowed suboptimal arc conversion, strongly implying that complement was activated via the alternative pathway. Quantification of the supernatant fluids showed dose-dependent complement consumption as defined by both CH100 immunoditfusion and CH50 tube haemolytic techniques. Airborne rye dust showed a greater quantitative potential than ground whole rye for activating the alternative pathway. These results indicate the possibility of the direct action of airborne organic dusts on the induction of inflammatory sequelae in the lungs of both sensitized and unsensitized individuals.  相似文献   
47.
75岁以上房颤患者的治疗   总被引:5,自引:0,他引:5  
房颤是成年人最常见的心律失常,其发生率是所有其他心率失常总和的2倍。发生房颤的平均年龄是75岁,在75岁以上年龄组,房颤的发生率是9%。  相似文献   
48.

Background

Radiofrequency ablation (RFA) was initially started by radiologists as a percutaneous treatment, but surgeons started to use RFA by surgical approach for patients with tumors at locations difficult for the percutaneous procedure. The aim was to evaluate the results of intraoperative RFA for small hepatocellular carcinomas (HCCs) (<3 cm) in locations difficult for a percutaneous approach.

Methods

Two hundred forty-seven patients with small solitary HCC (<3 cm) were treated; 196 via percutaneous RFA while 51 patients presented at sites not amenable for percutaneous route. Twenty-seven out of 51 patients underwent surgical resection, while 24/51 patients underwent intraoperative RFA.

Results

The location and depth of the tumor from the liver capsule was the only significant factors in the choice of the surgeon between resection and RFA. RFA was successful in all tumors (complete ablation rate of 100 %). In the surgery group, all patients achieved R0 resection. Complication rate was comparable (p?=?1.0). After a median follow-up of 37 months (range, 10–45 months), no tumors showed neither local progression nor local recurrence and no significant difference was observed between two groups as regards early recurrence and number of de novo lesions (p?=?0.49). One-year and 3-year survival rates were 93 % and 81 %, respectively, in the resection group comparable to the corresponding rates of 92 % and 74 % in the RFA group (p?=?0.9).

Conclusion

For small HCC in locations difficult for a percutaneous approach, intraoperative RFA can be an alternative option for deep-seated tumors necessitating more than one segmentectomy achieving similar tumor control, and overall and disease-free survival.  相似文献   
49.
This study provided a facile approach for the development of antifouling and antibacterial polyethersulfone (PES) composite film. Mainly, hyperbranched polyester-amide (PESAM) was used as both the reducing and capping agent for the in situ formation of AgNPs. The nanoparticles were intensively investigated using Fourier transform infrared spectroscopy (FTIR), ultra-violet spectroscopy (UV-vis), scanning and transmission electron microscopy (SEM & TEM) and X-ray diffraction (XRD). AgNPs were narrowly distributed with an average particle size of about 6 nm. PESAM was mixed with PES to realize free-standing film using the phase inversion method. The inclusion of PESAM in the composite film significantly improved hydrophilicity as confirmed by the contact angle measurements. Furthermore, SEM and EDX investigations confirmed that PESAM induced the in situ formation of AgNPs not only on the film surface but also inside its macro-voids. The composite film (PES/PESAM/Ag) displayed significant antibacterial potential against Gram positive and Gram negative bacteria. Overall, the described method paves the way towards development of advanced PES composite films with antimicrobial properties for broad application areas that include desalination membranes or active packaging materials.

This study provided a facile approach for the development of antifouling and antibacterial polyethersulfone (PES) composite film.  相似文献   
50.
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