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991.
A percentage of human T lymphocytes forms rosettes with autologous erythrocytes and this property has been considered as a marker for post-thymic precursor suppressor cells capable of providing suppression under the influence of inducer cells. We quantitated autologous rosette-forming T cells (ARFC) in the peripheral blood of 37 patients with chronic HBV infection: 8 healthy carriers, 9 chronic persistent hepatitis (CPH-B) and 20 chronic active hepatitis (CAH-B). Two control groups were studied, one consisting of 26 healthy individuals and the other of 8 individuals with non-HBV-associated CAH. Patients with non-HBV-associated CAH had a significant reduction in the proportion of ARFC, whereas CAH-B patients fell into 2 distinct patterns, one with increased and the other with decreased proportions of ARFC. This was unrelated to the degree of biochemical activity of the disease or to degree of viral replication as defined by HBeAg status and HBV-DNA in the serum. Healthy carriers and CPH-B had no changes in ARFC. Simultaneous quantitation of OKT4 and OKT8+ cells was done and a positive correlation was found between the proportions of ARFC and the proportions of OKT8+ cells. The possible significance of this correlation and the relevance of the bimodal distribution of autologous rosette-forming cells in CAH-B are discussed. 相似文献
992.
M G Bartels C K Varley J Mitchell S J Stamm 《Journal of the American Academy of Child and Adolescent Psychiatry》1991,30(1):100-103
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
C S Kase 《Alzheimer disease and associated disorders》1991,5(2):71-76
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.
F Biering-S?rensen J Lehmann Knudsen A Schmidt A Bundgaard I Christensen 《Paraplegia》1991,29(2):113-119
Ten tetraplegics, 8 males and 2 females, with a median age of 32 years participated in a scheduled 6 weeks training programme with a respiratory muscle training mouth-nose-mask (RMT-mask) with a fixed expiratory and an increasing inspiratory resistance set by the tetraplegic in accordance to his/her increasing ability during the training period. During the 6 weeks the tetraplegics required to use the RMT-mask for 15 minutes three times a day. Before and after each training session they measured peak flow (PEF). Lung volumes, ventilatory and diffusion capacity were measured before and after the 6 weeks training period. The training resulted only in a significant change in the PEF, which increased with 11% from 371 l/min before to 412 l/min in average after the 6 weeks of training (p less than 0.025). This statistically significant increase was confirmed by the measurements of PEF performed by the tetraplegics themselves during the training period. In addition there was an increase in PEF from before to immediately after each 15 minutes training session, this trend reached statistically significance (p less than 0.025) in the third '2 weeks period'. These results might indicate a possibility of improving the tetraplegics ability to cough by use of a simple RMT-mask, which in turn might prevent certain lung complications including pneumonia, and atelectasia. 相似文献
995.
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
996.
W D Lovan R A Weaver R J Lentz J K Goodrum B F Withers 《Aviation, space, and environmental medicine》1986,57(4):370-375
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
997.
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
998.
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
999.
1000.
M Altissimi R Antenucci C Fiacca G B Mancini 《Clinical orthopaedics and related research》1986,(206):202-210
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