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991.
In newly diagnosed adult patients with epilepsy followed prospectively on monotherapy, carbamazepine and phenytoin were associated with a fall in plasma uric acid, but sodium valproate and phenobarbitone were associated with a rise in plasma uric acid. The mechanisms and significance of these findings are discussed.  相似文献   
992.
Electrocardiograms were evaluated in 39 children and adolescents before and after the clinical use of imipramine and desipramine. The average increase in PR interval was 0.01 seconds. The PR interval increased by 0.02 seconds in 11 subjects, and a new first-degree atrioventricular block developed in two subjects. These changes were not related to the choice between imipramine and desipramine, the dose, or the method of administration. An increase in PR interval by 0.02 seconds or more did correlate with having an abnormality disclosed on a pretreatment electrocardiogram. The average increase in PR interval was 0.007 seconds for subjects with normal baseline electrocardiograms and 0.019 seconds for subjects with conduction and nonconduction abnormalities disclosed in baseline tracings. None of the electrocardiogram changes resulted in adverse clinical consequences.  相似文献   
993.
Epidemiology of multi-infarct dementia   总被引:2,自引:0,他引:2  
Multi-infarct dementia (MID), thought to result from the cumulative effect of repeated episodes of cerebral infarction, represents a sizable proportion of the dementia cases in the population. The frequency of MID as the cause of dementia is commonly quoted as 12-20%, but a more conservative figure on the order of 10% is suggested from prospective epidemiologic studies. Its prevalence increases steadily with advancing age, and a male predominance has been noted. Geographical variations in prevalence of MID may reflect true geographic/ethnic differences or lack of uniformity in the use of diagnostic criteria. Risk factors possibly associated with dementia after stroke include advancing age, previous cerebral or myocardial infarction, an atherothrombotic stroke mechanism, and cerebral atrophy as detected by imaging studies. In order to clarify the role of cerebrovascular disease as a cause of dementia, future epidemiologic studies should define the entity in precise terms, and place emphasis on clearly establishing the temporal relationship between stroke and dementia; new onset of dementia should be correlated with the clinical and anatomic features of the stroke.  相似文献   
994.
We report a case of mild visuo-spatial neglect consequent upon right-hemisphere stroke. At the time of testing, the patient had a complete left visual field deficit but only a very slight left hemiparesis. Under conventional testing conditions, line bisection performed with the right hand showed more severe left neglect than when performed with the left hand. This pattern of performance could, however, be modified, both quantitatively and qualitatively, by changing the starting position of the patient's hand when bisecting horizontal lines. The results suggest that spatio-motor cueing has a more profound effect upon task performance than does differential hemispheric activation per se. We also provide a demonstration that, in a normal subject, the starting position of the hand is likewise a crucial determinant of task performance. In this case, however, there is also an interaction between the hand (and hence hemisphere) deployed and the position of that hand in space.  相似文献   
995.
The Naval Special Board of Flight Surgeons was established in 1956 for the evaluation of Navy, Marine Corps, and Coast Guard problem aeromedical cases. This paper examines a sample 248 of these cases for the period of 1974-83 with respect to the characteristics of those referred, their referral diagnostic category, and the recommendation of the Special Board regarding return to a flying status. Those cases with a referral diagnostic category of ENT and Ophthalmology were less likely to be returned to flight status. Older, more senior pilots, and pilots with more total flight time were less likely to be returned to unrestricted flying than were their younger, more junior, and less experienced counterparts. Otherwise, no significant difference in outcome based on age, rank, marital status, branch of service, specialty, or flight hours was detected. Overall, 61% of those evaluated by the SBFS were returned to flight status.  相似文献   
996.
The expression of ras oncogene in normal and pathological liver disease   总被引:1,自引:0,他引:1  
Activation of the ras oncogene is associated with overproduction of the normal gene product (p21). Ninety one paraffin-embedded specimens were used to map the distribution of the normal form of p21 in normal, inflamed, cirrhotic and carcinomatous liver parenchyma. Monoclonal antibodies (Mo-RAP) were raised against the normal form of the ras-oncogene product and histological sections were stained by the peroxidase-antiperoxidase technique. Normal, inflamed and cirrhotic liver showed either minimal or moderate cytoplasmic staining. By contrast primary (n = 13) and secondary (n = 41) liver carcinomas exhibited intense staining. The differential pattern observed in p21 distribution could have useful clinical applications.  相似文献   
997.
The livers of 26 adult males with acquired immune deficiency syndrome (AIDS) were reviewed. The occurrence of portal tracts with diminished lymphocytes, probably reflecting generalized exhaustion of the lymphoid system, was a characteristic morphologic change, and was found in all cases. Kupffer cell hyperplasia was also a frequent finding and probably reflected generalized infection(s). Punched-out clusters of foamy histiocytes filled with acid-fast bacilli, typical for infection with Mycobacterium avium intracellulare (MAC), were found in three patients. In addition, MAC was cultured from two livers without the foamy histiocytic changes. Chronic viral hepatitis (three cases) and deposition of polarizable materials (one case) in the liver might be related to unusual habits of patients with AIDS. In conclusion, livers from patients with AIDS disclosed several kinds of lesions reflecting underlying or associated conditions in AIDS, but these did not contribute to the cause of death in our patients.  相似文献   
998.
999.
The long-term results of the conservative treatment of wrist fractures were observed in a follow-up study of 297 cases over a period of one and one-half years to six years. The evaluation of the results was based on clinical parameters, both subjective and objective, as well as radiological features. The results were: excellent in 38% of cases, good in 49%, fair in 11.5%, and poor in 1.5%; considerably worse were the subjective results (20% fair to poor). No statistically significant relation could be found between results and type of fracture. Clinical deformities and pain in the area of the distal radioulnar joint were frequent. Decrease in grip strength was observed in 17.8% of cases. A limitation of wrist movement was not frequent. Numerous compressive neuropathies were found (41 in 35 patients), especially of the median nerve. The values relative to the three radiographic parameters under investigation (that is, radial deviation, volar tilt, and radioulnar index) were often found to be out of the normal range. The comparative study of postreduction and follow-up radiograms show the loss of reduction to be frequent, especially as far as the volar tilt is concerned. The frequent radiologic deformities are associated with significantly bad results only in cases of extremely abnormal values. However, fractures of the distal radius are not to be underestimated. Long-term results following conservative treatment may not be as acceptable as is generally assumed.  相似文献   
1000.
Percutaneous transluminal angioplasty is a well established technique with wide application, but its place in the overall management of peripheral vascular disease is not well defined. This study compares similar groups of patients with peripheral vascular disease in 1981 and 1984, before and after the introduction of the technique to a district general hospital. More patients are now being investigated and treated and this is almost entirely due to the availability of angioplasty. The rates for surgery have not changed. Percutaneous transluminal angioplasty should therefore be seen as a new and separate form of treatment for peripheral vascular disease, not necessarily influencing or replacing surgery, and requiring its own allocation of resources in accordance with the increase in the level of care afforded by the technique.  相似文献   
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