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991.
Drainage of pelvic abscesses through the greater sciatic foramen 总被引:4,自引:0,他引:4
Butch RJ; Mueller PR; Ferrucci JT Jr; Wittenberg J; Simeone JF; White EM; Brown AS 《Radiology》1986,158(2):487-491
A computed tomographic (CT) guided transgluteal approach through the greater sciatic foramen was used to drain pelvic abscesses and fluid collections in 21 patients. Ideal catheter placement should traverse the lower portion of the greater sciatic foramen at the level of the sacrospinous ligament. This avoids the vascular and neural elements that are located slightly cephalad at the level of the piriformis muscle. Percutaneous drainage through this approach was successful in avoiding surgery in 17 patients (81%). Pain was the most common complication and was generally associated with a more cephalad approach, transgressing the piriformis and the sacral plexus. CT-guided percutaneous drainage of pelvic abscesses through the greater sciatic foramen should be used when the more standard transperitoneal approach is not possible. 相似文献
992.
993.
The contribution of different general practitioner characteristics, views, and experiences to the likelihood of their providing child health surveillance (CHS) was determined and their perceived training needs discovered. Family health service authority administrative data on the study population was combined with a postal questionnaire survey. Subjects were all general practitioners in three district health authorities in the North West Thames region. There were striking differences between districts in the proportion of practitioners undertaking CHS. General practitioners with paediatric training were three times more likely to do CHS. Women doctors were twice as likely to do CHS as men. The personal views of general practitioners were significantly associated with whether or not they undertook CHS. The CHS fee did not appear to be the major motivating factor. There was considerable demand for further training. The proportion of general practitioners undertaking CHS is likely to increase with the proportion of women and vocationally trained doctors. More local training is wanted, both by general practitioners already doing CHS and by those who would like to do it. Health authorities need to ensure that such training is convenient and continuing. 相似文献
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995.
996.
The time taken to collect high-resolution and high signal-to-noise (S/N) data in magnetic resonance (MR) imaging may be the limiting factor in patient throughput and in reducing patient motion. A hybrid fast-scan technique combining static and oscillatory phase-encoding gradients from two-dimensional Fourier transform (2DFT) and echo-planar imaging can reduce the time needed to collect data at the expense of loss in S/N. The flexibility of this technique is that any amplitude or frequency of oscillation of the phase-encoding gradient can be used. The technique was used for different frequencies and amplitudes, and images are presented that were acquired in one-half and one-quarter the time required with standard 2DFT techniques. The images illustrate that the hybrid and 2DFT techniques produce comparable resolution and contrast under identical conditions. 相似文献
997.
998.
Issues of confidentiality are complicated by the relationships we have to patients and others who have valid interests in the confidential information. There are no straightforward answers to problems which involve complex relationships and sensitive information. The best we can do is to think thoroughly and carefully about the issues in each case, and use our knowledge of the people involved to reach a decision. Doctors faced with difficult decisions of this kind should be assured that everyone finds them difficult. Sharing the burden with experienced colleagues can be helpful. 相似文献
999.
1000.
Notley LM De Wolf CJ Wunsch RM Lancaster RG Gillam EM 《Chemical research in toxicology》2002,15(5):614-622
Tamoxifen is a major drug used for adjuvant chemotherapy of breast cancer; however, its use has been associated with a small but significant increase in risk of endometrial cancer. In rats, tamoxifen is a hepatocarcinogen, and DNA adducts have been observed in both rat and human tissues. Tamoxifen has been shown previously to be metabolized to reactive products that have the potential to form protein and DNA adducts. Previous studies have suggested a role for P450 3A4 in protein adduct formation in human liver microsomes, via a catechol intermediate; however, no clear correlation was seen between P450 3A4 content of human liver microsomes and adduct formation. In the present study, we investigated the P450 forms responsible for covalent drug-protein adduct formation and the possibility that covalent adduct formation might occur via alternative pathways to catechol formation. Recombinant P450 3A4 catalyzed adduct formation, and this correlated with the level of uncoupling in the P450 incubation, consistent with a role of reactive oxygen species in potentiating adduct formation after enzymatic formation of the catechol metabolite. Whereas P450s 1A1, 2D6, and 3A5 generated catechol metabolite, no covalent adduct formation was observed with these forms. By contrast, P450 2B6, 2C19, and rat liver microsomes catalyzed drug-protein adduct formation but not catechol formation. Drug protein adducts formed specifically with P450 3A4 in incubations using membranes isolated from bacteria expressing P450 3A4 and reductase, as well as in reconstitutions of purified 3A4, suggesting that the electrophilic species reacted preferentially with the P450 enzymes concerned. 相似文献