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21.
During hemodialysis there is a complex interaction between the patient and the extracorporeal circuit that activates the complement system, among others. To better understand the influence of the dialyzer geometry and the dialysate composition, we compared hollow fiber versus parallel plate dialyzers and acetate versus bicarbonate dialysates and their role in the production of C3a, C4a and C5a. There was no significant difference in the plasmatic levels of these anaphylotoxins and their des-Arg derivates, as measured by RIA, in either dialyzer. The same was true when the dialysate in question had a different composition. We thus concluded that neither the geometric configuration of the dialyzer nor the composition of the dialysate influence their biocompatibility as regards the activation of the complement system, and that the differences that have been described shall have to be explained in another manner or assessed by methods other than those used in this study. 相似文献
22.
A J Herruzo L Martínez E Biel R Robles M A Rosales J A Miranda 《International journal of gynaecology and obstetrics》1991,36(1):17-22
We reviewed 488 twin pregnancies that resulted in the birth of neonates weighing 1000 g or more. Complications were present in 56.7% of all pregnancies; most common were threat of premature labor (17.4%) and preeclampsia (14.5%). Perinatal mortality was 31.8 per thousand. Eighty percent of neonatal deaths in twin pregnancies involved newborns weighing less than 2000 g. Twin pregnancies are high risk pregnancies and benefit from early diagnosis, prevention and treatment of the threat of premature birth. 相似文献
23.
In addition to its certification programme, which assesses the readiness of foreign medical graduates to enter graduate medical education programmes in the USA, the Educational Commission for Foreign Medical Graduates (ECFMG) is involved in a number of other programmes in international medical education. These include: (1) continuing to provide sponsorship for exchange visitors in graduate medical education programmes in the USA; (2) the development of a clinical skills assessment that is currently being introduced in pilot projects in the USA and abroad and will eventually become a component of the ecfmg certification process; (3) funding and administration of two fellowship programmes that provide foreign scholars (clinicians and basic scientists) with the opportunity to spend up to one year in a US medical school; (4) collaboration with the World Health Organization on the upcoming revised edition of the World Directory of Medical Schools ; and (5) co-sponsorship, with the World Health Organization, of a consultation on quality medical education oriented towards attaining a global consensus on the definition and the elements of quality in medical education and on the most appropriate ways to evaluate quality. 相似文献
24.
Miranda Jeanne James J. Gross Jacqueline B. Persons Judy Hahn 《Cognitive therapy and research》1998,22(4):363-376
Cognitive theory holds that dysfunctionalattitudes are important risk factors for depression.Critics have questioned this view, noting that, althoughdysfunctional attitudes are elevated in depression, they are not evident in vulnerable individualswho are asymptomatic. To deal with this criticism,Miranda and Persons (1988) have advanced the mood-statedependent hypothesis, which suggests that cognitive vulnerability factors are indeed present invulnerable individuals, but remain dormant untilactivated by negative mood. To test this hypothesis, 33women with and 67 women without histories of depression reported dysfunctional attitudes before andafter a film negative mood induction. As predicted,vulnerable subjects who reported increased negative moodreported increased dysfunctional attitudes.Unexpectedly, nonvulnerable subjects who reported increasednegative mood reported decreased dysfunctionalattitudes. These findings support the mood-statedependent hypothesis, and suggest that a deficit in theability to regulate negative emotions may be animportant feature of vulnerability todepression. 相似文献
25.
26.
In 260 asbestos-exposed individuals evaluated by means of computed tomography (CT), 43 unsuspected pulmonary masses were found in 27 individuals. The masses included fissural pleural plaques (n = 10), dense fibrotic bands (n = 3), round atelectasis (n = 11), carcinomas (n = 3), and other presumed benign masses (n = 16). The most helpful features in the diagnosis of rounded atelectasis with CT were (a) contiguity to areas of diffuse pleural thickening, (b) a lentiform or wedge-shaped outline, (c) evidence of volume loss in the adjacent lung, and (d) a characteristic "comet tail" of vessels and bronchi sweeping into the margins of the mass. Less advanced areas of focal atelectasis had fewer classic features. Intrafissural pleural plaques were readily identified with high-resolution CT. In asbestos-related masses, the demonstration of stability over time is necessary. Careful interpretation of CT and high-resolution CT features and close surveillance can obviate the need for biopsy in the majority of instances. 相似文献
27.
28.
The intercellular adhesion molecule (ICAM) family of proteins 总被引:8,自引:0,他引:8
Macromolecular adhesive associations between cells are important for transmitting spatial and temporal information that is
critical for immune system function. One such group of proteins, the intercellular adhesion molecules (ICAMs), has grown as
newly identified members are revealed. In addition, the functions of the ICAMs, in general, have begun to be better understood,
including intracellular signaling events. This information has led to the design of novel therapeutic agents that may prove
effective in a variety of disease states. 相似文献
29.
Swiedler SJ Beck M Bajbouj M Giugliani R Schwartz I Harmatz P Wraith JE Roberts J Ketteridge D Hopwood JJ Guffon N Sá Miranda MC Teles EL Berger KI Piscia-Nichols C 《American journal of medical genetics. Part A》2005,(2):144-150
A cross-sectional survey in individuals affected with the lysosomal storage disease Mucopolysaccharidosis VI (MPS VI) was conducted to establish demographics, urinary glycosaminoglycan (GAG) levels, and clinical progression of the disease. The survey evaluated 121 bona fide MPS VI-affected individuals over the age of 4 years from 15 countries across the Americas, Europe, and Australasia representing greater than 10% of the estimated world prevalence of the disease. A medical history, complete physical exam, urinary GAG determination, and assessment of several clinical measures related to physical endurance, pulmonary function, joint range of motion, strength, and quality of life were completed for each participant. Although a wide variation in clinical presentation was observed, several general findings were obtained reflecting progression of the disease. Impaired physical endurance, as measured by the distance achieved in a 6-min walk, could be demonstrated across all age groups of MPS VI-affected individuals. High urinary GAG values (>200 mug/mg creatinine) were associated with an accelerated clinical course comprised of age-adjusted short stature and low body weight, impaired endurance, compromised pulmonary function, and reduced joint range of motion. An unexpected result was the predominance of urinary GAG values <100 mug/mg creatinine for those participants over the age of 20 years. Pending the collection of longitudinal data, these results suggest that urinary GAG levels predict clinical morbidity, and longer-term survival is associated with urinary GAG levels below a threshold of 100 mug/mg creatinine. 相似文献
30.