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61.
Carotenoids are exclusively transported by lipoproteins; in vitro studies suggest that they might protect these particles against oxidation. Little is known about the factors that govern the distribution of these micronutrients among lipoproteins. The objective of this study was to assess whether carotenoids are exchanged between lipoproteins and what factors, if any, were involved. In the first experiment, different groups of trout were fed for five days with either a carotenoid-free diet or with diets containing 80 mg pure carotenoid per kilogram of feed. Lipoproteins were separated by ultracentrifugation and carotenoid-rich, high-density lipoproteins (HDL) were incubated for two hours at 37 degrees C with carotenoid-free, very low-density lipoproteins (VLDL), and vice versa. After incubation, lipoproteins were re-separated and carotenoids were quantified to measure the transfer. The same experiments were done in the presence of cholesteryl ester transfer protein (CETP) and lecithin cholesterol acyltransferase (LCAT) inhibitors. In a second experiment, the exchange was measured between human VLDL and HDL. In trout, incubation of carotenoid-rich HDL with carotenoid-free VLDL resulted in the appearance of carotenoids in VLDL, and inversely. The higher the hydrophobicity of a carotenoid, the lower its proportion in HDL after incubation. CETP and LCAT inhibitors significantly increased the proportion of carotenoids in HDL after incubation. Results obtained with human lipoproteins showed that the xanthophyll lutein transferred between lipoproteins, but could not show any carotenes (alpha-carotene, beta-carotene, and lycopene) transfer. We conclude that carotenoids, chiefly the xanthophylls, exchange between lipoproteins. The transfer depends on plasma factor(s) sensitive to CETP and/or LCAT inhibitors.  相似文献   
62.
Serum TeBG binding capacity was measured in 8 cord blood samples, and in peripheral venous blood from 39 male and 31 female infants aged from 1 day to 1 year. In cord blood, TeBG binding capacities were low (1.27 +/- 0.3 microgram/100 ml) with no sex difference. In male infants, TeBG binding capacities increased progressively from birth to 3 months, before decreasing to reach the normal prepubertal level at 6 months. Individual values ranged between 1.16 and 14.5 microgram/100 ml and were significantly correlated with plasma testosterone (r = 0.671, 95% confidence limits 0.440 to 0.818, p less than 0.005) and estradiol (r = 0.734, 95% confidence limits 0.121 to 0.942, p less than 0.01) levels. In female infants, individual values ranged between 1.17 and 14.5 microgram/100 ml, without correlation with age or plasma estradiol level. In male infants the data suggest a positive control ot TeGB binding capacity by estrogens, the negative effect of testosterone being delayed until after the 3rd month of age. In girls, the lack of correlation between TeBG and estradiol can probably be explained by rapid variations of plasma estradiol levels.  相似文献   
63.
64.
A study of 77 consecutive cases of childhood rhabdomyosarcoma treated initially at the Children's Hospital of Los Angeles from 1950 to 1972 demonstrated an impressive improvement in survival of patients when intensive chemotherapy was combined with surgery and radiation therapy. The major improvement in survival occurred in Stage II and Stage III disease. Eight out of 9 patients with a primary lesion of the lower extremities developed intra-abdominal disease. A general approach for treatment of Stage II, III, and IV rhabdomyosarcoma is proposed which involves intensive chemotherapy, following biopsy, as the principle treatment, with radiation and surgery used as adjuvants.  相似文献   
65.
66.
We assessed the effect of CD34+ cell dose on costs in breast cancer patients undergoing autologous peripheral blood stem cell (PBSC) transplantation. Mean hospitalization costs were 26,992.9+/-9582.9 for patients receiving a CD34+ cell dose <5 x 10(6) cells/kg versus 22,339.4+/- 5471.1 for those receiving >5 x 10(6) CD34+ cells/kg (p=0.0065).  相似文献   
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68.
The implication of integrated functional sensory relations of the body to space in anxiety disorders is a very important issue which encourages the development of animal models, in particular, for pharmacological perspectives and for the functional assessment of the deficits induced by genetic manipulation in the mouse or the rat. A new experimental device is presented here: It is comprised of a rotating tunnel and a rotating-beam controlled by computer which can be used for multiple visuo-idiothetic and kinesthetic sensory conflict situations during active locomotor behaviour by mice. The system is linked to a digital video system, Video-Track trade mark, designed to track and record the movements of the animals. Anxious BALB/cByJ mice were compared to non-anxious C57BL/6J mice and were seen to display highly disturbed locomotor behaviour in a sensory conflict situation. The model highlights the advantages of video-digital analysis for animal behavioural sciences.  相似文献   
69.
Cerebral malaria (CM), one of the most common fatal complications of the heterogenous syndrome named severe malaria, is indubitably a post-infectious neurovascular pathology, as evidenced by histopathological analyses. This neurological syndrome is characterised not only by the cytoadherence of Plasmodium falciparum-infected erythrocytes, but also by morphological and functional alterations of brain microvascular endothelial cells subsequent to their interactions with circulating cells, such as platelets, monocytes, lymphocytes, and dendritic cells. During CM, host cells, in particular immune cells, are found recruited and activated at the site of sequestration, where they release various soluble molecules. Among these, cytokines play a major role in CM pathogenesis. Indeed, cerebral complications appear to be due to an imbalance between pro-inflammatory and anti-inflammatory mediators. Cytokines (notably interferon-gamma, tumour necrosis factor, lymphotoxin) and chemokine receptors (notably CCR5) are also responsible for blood-brain barrier alterations and biochemical changes leading to the brain parenchymal lesions that can be observed in CM. In return, glial cells can influence blood-borne elements, and thereby worsen the pathology. Numerous problems remain to be solved, especially the sequence of pathological events, namely the order in which the circulating cells sequester on the endothelial wall. A better understanding of the molecular mechanisms involved in CM pathogenesis is needed if we are capable of preventing cerebral complications and improving the quality of patient management.  相似文献   
70.
A relatively rare case of ball-throwers fracture of the humerus is presented. Severe muscular action is an uncommon cause of humeral fractures but has been well documented in the orthopedic literature. To our knowledge, this fracture has not been described in the radiology literature, and awareness of this entity could preclude further unnecessary workup. The mechanism of injury and its typical radiographic appearance is described.  相似文献   
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