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101.
Twenty-two adult patients with uncontrolled epilepsy and severe learning difficulties were included in an open study of vigabatrin. Patients were all in residential care and had experienced at least 12 seizures during the previous 12 months despite all attempts to optimize antiepileptic drug (AED) treatment. Following a 4 month baseline period, vigabatrin 500 mg twice daily was added to the current AED treatment and the dose increased according to response, up to a maximum of 4 g/day. Ten patients achieved a reduction in seizure frequency of more than 50% during this 4 month dose titration phase. Two patients had no seizures during the baseline period. For the 30 patients with seizures during the baseline period the median improvement in seizure frequency with the addition of vigabatrin was 49% (P = 0.014). The response rate was higher for patients with partial seizures than for those with generalized seizures. Ten patients continued with vigabatrin while the dose of one of their other AEDs was gradually reduced and successfully withdrawn in three patients. Adverse events were reported in 20 patients during the 64 week study period. The most frequently reported events were sedation (8 patients), aggression (4 patients), agitation (3 patients) and ataxia (3 patients). No patients were withdrawn from the study as a consequence of adverse events. Vigabatrin was therefore an effective add-on therapy in 45% of these difficult-to-treat patients and allowed reduction of other AED treatment in a small number. 相似文献
102.
Self-expanding endovascular graft: an experimental study in dogs 总被引:2,自引:0,他引:2
T Yoshioka K C Wright S Wallace D D Lawrence C Gianturco 《AJR. American journal of roentgenology》1988,151(4):673-676
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
103.
The pathogenesis of hypertension in autosomal-dominant polycystic kidney disease (ADPKD) is unclear, but increased activity of the renin-angiotension system may contribute. The renal and systemic hemodynamic response to lisinopril, an angiotension converting enzyme (ACE) inhibitor, in patients with ADPKD without renal failure was compared with the response in matched unaffected family members. Mean blood pressure and renal vascular resistance decreased in the affected group after lisinopril, with no significant change in the unaffected group. Glomerular filtration rate (GFR) was unchanged and therefore filtration fraction fell significantly. Changes in urinary excretion of 6-keto-PGF1 alpha and kallikrein suggested that increased renal synthesis of PGI2 or activation of the renal kallikrein-kinin system were not likely to be responsible for the hemodynamic effects. The acute decrease in renal vascular resistance without change in GFR suggests that ACE inhibition may have a particular value in the treatment of hypertension associated with ADPKD which should be assessed by further long-term studies. 相似文献
104.
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
105.
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
106.
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
107.
Acute impairment of regional myocardial glucose uptake in the apical ballooning (takotsubo) syndrome
Kevin A. Bybee Joseph Murphy Abhiram Prasad R. Scott Wright Amir Lerman Charanjit S. Rihal Panithaya Chareonthaitawee 《Journal of nuclear cardiology》2006,13(2):244-250
BACKGROUND: Apical ballooning syndrome (ABS) is a poorly understood clinical entity characterized by acute, transient systolic dysfunction of the left ventricular (LV) apex in the absence of epicardial coronary artery disease and commonly associated with acute emotional stress. We report abnormal regional myocardial perfusion and glucose uptake in 4 consecutive ABS patients studied using positron emission tomography with 13N-ammonia and 18F-fluorodeoxyglucose within 72 hours of presentation with ABS. METHODS: All patients were postmenopausal females, 3 of whom had a major recent life stress event. Coronary angiography revealed no or minimal obstructive epicardial coronary artery disease. All patients exhibited reduced glucose uptake in the mid-LV and apical myocardial segments, which was out of proportion to perfusion abnormalities in half of the cases. CONCLUSION: In all 4 patients, affected regions subsequently recovered regional LV systolic function within 6 weeks. 相似文献
108.
J G Wright R J Tesi D W Massop M L Henry J R Durham R M Ferguson W L Smead 《American journal of surgery》1991,162(2):126-130
Patients with aortic disease and end-stage renal failure who require both aortic reconstruction and renal transplantation (simultaneously or staged) pose a formidable clinical challenge. Traditionally, the performance of either one of these procedures has been viewed as a relative contraindication to the performance of the other. From 1978 to 1989, eight patients were referred to us with the combination of aortic disease and end-stage renal failure. Seven had aneurysmal disease and one had aorto-iliac occlusive disease. Five patients presented with their diseases sequentially and had two sequential operations, with a mean interval of 4 years between procedures. Three patients presented with their diseases simultaneously and underwent simultaneous aortic reconstruction and living related renal transplantation. All patients were followed up for a mean interval of 4.5 years. By life-table analysis, the 5-year renal graft survival was 100%, the primary aortic graft patency was 82%, and the secondary aortic graft patency was 100%. The only death in this series occurred 11 years after aortic reconstruction and 4 months after a renal transplantation and was due to overwhelming cytomegalovirus sepsis. There were no significant differences between the simultaneous and staged groups in terms of operative mortality, postoperative complications, transplant function, or aortic graft patency. From this experience, we conclude that: (1) patients who present simultaneously with aortic disease and end-stage renal failure can safely undergo simultaneous aortic reconstruction and renal transplantation; (2) patients who present with these two diseases sequentially can undergo a second reconstructive procedure with very low operative morbidity and mortality rates; (3) when these two procedures have been performed sequentially, the second procedure has not significantly altered the 30-day or 5-year results of the first procedure; and (4) the 30-day and 5-year results of each procedure have been excellent regardless of the temporal sequence in which they were performed. 相似文献
109.
A photometric study of the effect of pupil dilatation on Nd:YAG laser iridotomy area was performed in 21 eyes of 21 patients. The iridotomy area was 0.075 (0.055) mm-2 (mean (SD)) before pupil dilatation and 0.073 (0.070) mm-2 after pupil dilatation (t test NS). Iridotomy area after pupil dilatation correlated with iridotomy area before pupil dilatation (r = 0.815, p < 0.01) but did not significantly correlate with measures of iridotomy shape or position, or with changed iris area following pupil dilatation. Two iridotomies became reduced to less than 20% of their initial area following pupil dilatation. Our findings suggest that the only effective method of avoiding development of unacceptably small iridotomy area after pupil dilatation is to create a sufficiently large iridotomy at the time of initial laser surgery. 相似文献
110.