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991.
Histological studies describe in detail the changes of the small arteries wall with controversial results concerning lumen narrowing during the aging process. In this study, the anatomic and the angiographic parameters of the medial and lateral lenticulostriate arteries were analysed in 64 carotid angiograms. Only 20% of the total number of lenticulostriate arteries were shown on angiograms. Collateral branches were rarely visible, especially those of medial group. The course of the lenticulostriate arteries was mostly straight or moderately tortuous. No significant differences were noted in any of the measured parameters when compared with the age (p greater than 0.05). It appears that age-related changes spread over external layers of small arteries, with no lumen narrowing or filling defect.  相似文献   
992.
J Strausz  S Kis  J Juhász  A Bede  J Elek  Z Monostori  G Nagy  I Repa 《Orvosi hetilap》1992,133(36):2293-2296
Six patients with obstruction of the trachea were treated with silicone rubber endothracheal stents implanted with flexible bronchoscope. In every case the stent caused significant clinical improvement of the ventilation. At the postintubation stenosis the stent can result a final recovery, at the malignant processes the implantation seems to be a new palliative method.  相似文献   
993.
Using high-performance liquid chromatography and gas chromatography, we reevaluated the 24-h influence of a serotonin- and dopamine-rich diet on platelet serotonin and serotonin, 5-hydroxyindoleacetic acid (5-HIAA), and major catecholamine metabolites in the urine of 15 healthy adults. Although there were significant responses in urinary free serotonin and catecholamine metabolites, their concentrations did not exceed the upper limits of the reference ranges for any of the participants. For urinary 5-HIAA, pronounced effects were observed within 2-4 h. After 6-8 h, results for 11 participants exceeded the upper limit of the reference range. The median recovery of dietary serotonin as urinary 5-HIAA was 20% and subject to a large range (1-50%). There was no significant change in platelet serotonin. We conclude that, using specific analytical methods, no dietary restrictions need be imposed to diagnose catecholamine (metabolite)-producing tumors. For diagnosis of carcinoids on the basis of urinary 5-HIAA it is appropriate to completely abstain from serotonin-containing foods for greater than or equal to 12 h before testing. Platelet serotonin is a more sensitive marker for carcinoids that produce only small amounts of serotonin, and is unaffected by dietary serotonin.  相似文献   
994.
The expression of surface tissue factor procoagulant activity and its shedding by blood monocytes can be induced by several stimuli. Few of these defined situations, other than the presence of bacteria and their toxins, are commonly present in the young human infant. In this study, measurements were made of the percentage of monocytes expressing surface tissue factor apoprotein (TFA) in blood taken from babies in the early weeks of life. Mononuclear cells were separated from blood in an environment free of detectable endotoxin. After exposure to a polyclonal rabbit antibody raised to purified brain TFA and subsequent exposure to a fluorescin-labeled murine anti-rabbit IgG, the cell fluorescent activity was analyzed by flow cytometry. The percentage of monocytes showing strong fluorescence was determined. In every instance when systemic bacterial infection was present, more than 60% of the monocytes examined showed fluorescence indicative of the presence of surface TFA. In a single case of fungal Candida septicemia, none of the monocytes was positive. More than 60% of cells were found to be positive in certain instances where infection was highly probable but not proven. Positive cells were found in three cases of isoimmune hemolytic disease of the newborn, as had been anticipated from previous studies, whereas less than 25% of monocytes derived from babies in the absence of discernible infection or isoimmune hemolytic disease expressed surface TFA (p less than 0.001). These findings provide insight into a possible mechanism of coagulation activation in sepsis and may prove to be a useful predictor of the presence of infection or endotoxemia in young infants.  相似文献   
995.
Spectral analysis was employed to assess the electric activity of the stomach and intestine from the body surface. Equipment including a microcomputer and a specially designed program were used. Examinations of 134 normal subjects and patients with various gastrointestinal conditions have demonstrated a sufficient accuracy of the method in the detection of gastrointestinal dyskinesia and in assessment of gastrointestinal function, as well as in presentation of individual elements of regular gastrointestinal activity.  相似文献   
996.
Clinical observations and laboratory experiments have suggested a role for testosterone in the development of prostatic cancer. Since physical training may act to lower testosterone levels, men who are very active may have a reduced risk of this cancer. To test this hypothesis, the authors prospectively followed 17,719 Harvard alumni (aged 30-79 years) from 1965 or 1969 to 1977, and 1980 to 1988 for the occurrence of prostatic cancer (n = 419). Physical activity was assessed in either 1962 or 1966, and again in 1977, based on self-reported stair climbing, walking, and sports played. Alumni who expended greater than 4,000 kcal/week at both assessments were at reduced risk of developing prostatic cancer (age-adjusted rate ratio, 0.12; 95% confidence interval 0.02-0.89) compared with their inactive counterparts who expended less than 1,000 kcal/week at both assessments. These results should be interpreted cautiously, since only one case of prostatic cancer was identified among alumni highly active at both assessments, who contributed 4% of total person-years to the analysis. Among alumni aged 70 years and older, those who extended greater than 4,000 kcal/week at either assessment had about half the risk of those who expended less than 1,000 kcal/week at either assessment (age-adjusted rate ratio, 0.53; 95% confidence interval 0.29-0.95). The authors attribute these findings to the increased precision with which physical activity could be measured when combining two activity assessments. Alternatively, long-term maintenance of a high level of physical activity may be necessary for further reduction of risk. There was no evidence of a dose-response relation.  相似文献   
997.
Toxoplasma encephalitis is the commonest cause of intracranial mass lesions in AIDS patients. Effective therapy includes pyrimethamine plus sulfadiazine, clindamycin with pyrimethamine, and co-trimoxazole. This study examines the efficacy of oral co-trimoxazole in 20 AIDS patients with toxoplasmosis and seeks to confirm the experience of Torre et al.  相似文献   
998.
In the random sample of 762 males aged 30-59 years who had moved to Chukotka, the attitude towards their health, a physician, bad habits, and prevention of diseases was examined within the Programme on Epidemiology of Major Non-Communicable Diseases and Their Risk Factors among the residents of the Chukotsky Autonomous District. The non-aboriginal Chukotka's population having higher risk factors showed decreased self-appraisal of their health, inadequate awareness of their health and risk factors for diseases. However, the majority of the male population consider it useful to be surveyed, which should be borne in mind in implementing educational measures among these population groups.  相似文献   
999.
The role of interleukin 6 (IL-6) in the growth of five multiple myeloma-derived cell lines was characterized. The U266 and RPMI 8226 cell lines demonstrated increased DNA synthesis when cultured with exogenous IL-6, expressed IL-6 cell surface receptors (IL-6Rs) and expressed mRNA for IL-6R. However, these cells did not secrete detectable IL-6 protein, and a neutralizing antibody to IL-6 did not inhibit their growth. Three other myeloma-derived cell lines ARH-77, IM-9 and HS-Sultan did not respond to exogenous IL-6, secrete IL-6 or express cell surface IL-6Rs. The IL-6 responsive cell lines bore late B-cell surface antigens (Ags), CD38 and PCA-1, whereas those lines which were non-IL-6 responsive strongly expressed B1 (CD20) and B4 (CD19) Ags, representing earlier stages in B-cell differentiation. Finally, the two IL-6 responsive cell lines did not express Epstein-Barr virus (EBV) proteins; in contrast, EBV encoded proteins typically expressed during latency could be detected in the three non-IL-6 responsive lines, confirming infection with virus. These studies clarify the heterogeneity observed in the myeloma cell line phenotype and biology and suggest that the U266 and RPMI 8226 cell lines, which express IL-6 cell surface receptors and are IL-6 responsive, may be useful for further study of IL-6 signal transduction in and related IL-6 mediated growth of myeloma in vivo. In contrast, those cell lines which are IL-6-independent provide a model for further study of EBV transformation and IL-6-dependent growth mechanisms in malignancy.  相似文献   
1000.
Blink reflex abnormalities in children with Tourette syndrome   总被引:1,自引:0,他引:1  
Tourette syndrome (TS) is a common disorder which typically occurs during childhood or early adolescence. There is no definitive diagnostic test for TS. The objective of this study was to demonstrate whether neurophysiological abnormalities of the blink reflex can be observed in children with TS. We enrolled 15 children with TS, diagnosed according to DSM IV Diagnostic Criteria, and 15 controls. The blink reflex was elicited by stimulating the supraorbital nerve in order to measure the early response (R1), homolateral and contralateral R2 (late) responses, amplitude of R1 and duration of R2. The mean duration of R2 was significantly longer in TS patients than in the controls ( P  < 0.001, Student's t -test). An abnormal pattern of the blink reflex can be, even in childhood, an early neurophysiologic marker of TS, which is not related to the duration of TS or to the age of onset.  相似文献   
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