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81.
Self-expanding endovascular graft: an experimental study in dogs   总被引:2,自引:0,他引:2  
An arterial endovascular graft was constructed by wrapping an expandable nylon mesh around a framework of Gianturco self-expanding metallic stents. The devices were passed through a 12-French Teflon catheter and positioned in the normal abdominal aorta of five dogs, two of which also had a device placed in an external iliac artery. At follow-up (1-6 months), all grafts remained patent, even though slight luminal narrowing due to neointimal encasement was noted. Histologically, all grafts were covered by neointimal proliferation at the time of removal. The graft material expanded with the stents, resulting in a tight fit between the graft and the vessel wall. Side branches narrowed but remained open because of the size of the nylon mesh. No migration of the grafts equipped with a barbed lead stent was noted. Expandable nylon mesh can be used as an endovascular graft material when wrapped around a framework of self-expanding stents. The resulting device can be easily delivered via transcatheter techniques, and once placed in a vessel, the nylon acts as a support for neointimal encasement, which forms a new vascular lumen.  相似文献   
82.
After observing an association between vitamin A deficiency and otitis media among children in Micronesia, we sought to develop an animal model for vitamin A-deficiency-induced otitis media. Thirty juvenile guinea pigs were screened for absence for otitis and then divided into two groups. The experimental group was placed on a vitamin A-free diet, whereas control animals were fed a standard formula. The animals were followed by means of otologic examination and serum retinol determinations. When experimental animals demonstrated vitamin A deficiency, they were killed along with one control and temporal bones were harvested and prepared for histologic examination. None of the 15 controls demonstrated middle ear abnormalities. In the experimental group, 77% of temporal bones showed middle ear pathology consisting of either of subepithelial edema (27%) or frank otitis media (50%). These results indicate that the guinea pig is a suitable species for study of otitis media in association with vitamin A deficiency. We postulate that eustachian tube dysfunction is the primary mechanism for inducing middle ear inflammation in this animal model.  相似文献   
83.
Seventeen of 25 patients with myotonic dystrophy had moderate to severe hearing loss, usually sensorineural, that was identified by routine audiometric screening and was treatable in some patients. Further testing failed to reveal a single pathophysiological process.  相似文献   
84.
Although the Willoughby Personality Questionnaire and the Fear Survey Schedule are demonstrably valuable aids to the practice of behavior therapy of neurosis, it is evident that many behavior therapists do not use them. In order to determine the extent of their neglect, we sent a questionnaire to all Clinical Fellows of the Behavior Therapy and Research Society. The 134 replies we received revealed that the Willoughby was routinely used by only 19% and the Fear Survey Schedule by only 42%. This seems to be manifestation of a wide-spread but indefensible homogenized view of neuroses. It is a sad reflection on the quality of behavior therapy training programs.  相似文献   
85.
The intestinal absorption of molybdenum in healthy human volunteers has been measured by simultaneous oral and intravenous administration of the stable isotopes 95Mo and 96Mo, and the results were analysed using the convolution integral technique. The results showed that molybdenum ingested in liquid form was rapidly and totally absorbed into the circulation under ordinary intake regimes. The rates and extent of absorption were lower for composite meals, and also for increasing levels of administration. This information can be helpful in the application of the new ICRP model of the human alimentary tract.  相似文献   
86.
87.
Sixty women with breast cancer (mean age: 61 years; range 36-78 years) were treated with Epirubicin (4’epi-Dox-orubicin), 60 mg m-2 , as single drug therapy. The drug was administered as 2 hours’ constant rate infusions. The pharmacokinetics of the drug during the first course of treatment was evaluated by measurements of the plasma concentration of Epirubicin at the end of the infusion period. There was a five-fold inter-individual variation of the dose-normalized maximum plasma concentration, which increased with increasing age of the patients. There was no correlation between this pharmacokinetic parameter and degree of obesity.  相似文献   
88.
A device called the Dex Frame has recently been marketed as an aid for children with specific learning difficulties. Using a test of reading speed and a test of reading accuracy we have attempted to evaluate the device. Two groups of children with learning difficulties were used, one having sole use of the device and being allowed to carry it with them and a second group who only used the device when attending for remedial tuition and assessment. The results show that no significant improvement occurred in reading performance of the groups with learning difficulties using the Dex Frame as compared with a control group. The teachers of the groups did, however, feel that on an individual basis some children (< 10%) expressed that they felt more comfortable using the device.  相似文献   
89.
90.
Chlamydia trachomatis was researched from 400 pregnant women. 76 of them were found infected and 129 carried serological signs of infection. We purpose a detection at the end of pregnancy interesting women with sexually transmitted diseases background and those with serological positive results (greater than 1/64). Then, treatment of the mother will be an useful method of prevention against neonatal infection.  相似文献   
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