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71.
72.
Pigeyre M Duhamel A Poulain JP Rousseaux J Barbe P Jeanneau S Tibère L Romon M 《Appetite》2012,58(2):703-709
Although the prevalence of obesity is higher in low socioeconomic position (SEP), the relationship between SEP and body mass index (BMI) differs according to gender. The purpose of this study is to investigate the relationships between BMI and SEP according to gender and explore the weight-related behaviors. In a cross-sectional survey, 1646 French adults were weighed and answered a questionnaire about eating behavior (DEBQ), SEP markers, ideal weight perception, physical activity and smoking. Our study showed that BMI was inversely correlated with SEP score in women only, independently of other BMI-associated factors (age, restrained eating, smoking status, TV viewing and physical activity). The SEP gradient was the same in both genders for some weight-related behaviors, such as restrained eating, physical activity and TV viewing, but differs for others, such as smoking and weight consciousness. There was an interaction between the SEP score and the actual BMI on the ideal BMI in women only, thus the difference in ideal body weight according to SEP is mainly due to difference in obese women. Our study concluded that gender differences in the relationship between BMI and SEP could be mainly due to the subjects' perception of weight appropriateness and their weight-related behaviors. 相似文献
73.
On the interaction of rabbit antithrombin III with the luminal surface of the normal and deendothelialized rabbit thoracic aorta in vitro 总被引:2,自引:0,他引:2
Pure rabbit antithrombin III was isotope labeled (with 125I or 3H) by two different methods; neither procedure caused a loss of antithrombin activity although both methods affected the affinity of the protein for Sepharose-heparin. From segments from freshly excised rabbit aorta, the uptake of isotope-labeled antithrombin III by the endothelium was rapid and saturable, although relatively small compared to the uptake of thrombin; binding of 3H-antithrombin III to the endothelium resembled that of 125I-antithrombin III. Transendothelial passage of antithrombin III into the subendothelial layers (intima-media) was slow and progressive. Endothelium binding was not affected by pretreating the vessel with either heparin, thrombin, or glycosaminoglycan-specific enzymes. Endothelium-bound antithrombin III was not selectively displaced by either heparin or thrombin. In contrast, endothelium-bound thrombin was rapidly dislodged by antithrombin III as a thrombin- antithrombin III complex. The surface of the deendothelialized aorta (ie, subjected to a balloon catheter) bound antithrombin III avidly. Pretreatment of the deendothelialized vessel with glycosaminoglycan- specific enzymes, particularly heparitinase, decreased intima-media binding by up to 80%. 125I-antithrombin III, when bound to the deendothelialized vessel surface, was actively displaced by either heparin, thrombin, or by unlabeled antithrombin III. The relatively poor binding of antithrombin III compared with that of thrombin by the endothelium in vitro supports an earlier proposal (Lollar P, Owen WG: J Clin Invest 66:1222-1230, 1980) that thrombin bound to high-affinity sites, possibly pericellular proteoglycan, of the endothelium is inactivated by plasma antithrombin III in vivo. Such a situation probably holds for large arteries at least. 相似文献
74.
Conditions were developed in which 80% to 90% of platelet fibrinogen could be routinely purified in nondegraded form from the fluid phase of platelet suspensions stimulated with the calcium ionophore, A23187, in the presence of calcium, leupeptin, and prostaglandin E1. Fibrinogen was separated from other released proteins by chromatography on diethylaminoethanol (DEAE)-cellulose using a continuous pH and ionic strength gradient. Purified platelet fibrinogen, greater than 98% homogeneous by immunoelectrophoresis and sodium-dodecyl sulfate- polyacrylamide gel electrophoresis (SDS-PAGE), consisted of intact A alpha, B beta and gamma A chains, but not gamma' chains, and was 95% to 96% clottable. Platelet fibrinogen was shown to compete for the binding of radiolabeled plasma fibrinogen to ADP-activated platelets in a manner identical to that of unlabeled plasma fibrinogen itself. Also, at equivalent protein concentrations, platelet and plasma fibrinogens supported platelet aggregation to an equivalent extent. Based upon these results, we conclude that there is no significant difference between platelet and plasma fibrinogen with respect to their size, their clottability, their affinity for the activated platelet fibrinogen receptor, or their capacity to support subsequent platelet aggregation. 相似文献
75.
The authors report a case of dolichoectasic intracranial arteries associated with an aneurysm of the abdominal aorta. The patient presented with a double hemorrhagic vascular rupture, the abdominal aortic aneurysm being operated on as an emergency, with a favorable outcome. The cerebral and aortic angiograms showed extension of the pathological process to the large caliber arteries. Microcirculatory investigations at the nail bed and conjunctiva also showed distal lesions. The vascular abnormality underlying these multiple ectasic lesions would seem to be different to that of classical arteriosclerosis. Anatomopathological studies reported in the literature describe fibrous degenerative lesions of the media differing from those observed in fibromuscular dysplasia. 相似文献
76.
Dercksen MW; Weimar IS; Richel DJ; Breton-Gorius J; Vainchenker W; Slaper- Cortenbach CM; Pinedo HM; von dem Borne AE; Gerritsen WR; van der Schoot CE 《Blood》1995,86(10):3771-3782
In the present study, we show by adhesion assays and ultrastructural studies that platelets can bind to CD34+ cells from human blood and bone marrow and that this interaction interferes with the accurate detection of endogenously expressed platelet glycoproteins (GPs). The interaction between these cells was found to be reversible, dependent on divalent cations, and mediated by P-selectin. Enzymatic characterization showed the involvement of sialic acid residues, protein(s). The demonstration of mRNA for the P-selectin glycoprotein ligand 1 (PSGL-1) in the CD34+ cells by polymerase chain reaction (PCR) analysis suggests that this molecule is present in these cells. Under conditions that prevent platelet adhesion, a small but distinct subpopulation of CD34+ cells diffusely expressed the platelet GPIIb/IIIa complex. These cells were visualized by immunochemical studies. Furthermore, synthesis of mRNA for GPIIb and GPIIIa by CD34+ cells was shown using PCR analysis. The semiquantitative PCR results show relatively higher amounts of GPIIb mRNA than of PF4 mRNA in CD34+CD41+ cells in comparison with this ratio in platelets. This finding is a strong indication that the PCR results are not caused by contaminating adhering platelets. MoAbs against GPIa GPIb alpha, GPV, P- selectin, and the alpha-chain of the vitronectin receptor did not react with CD34+ cells. The number of CD34+ cells expressing GPIIb/IIIa present in peripheral blood stem cell (PBSC) transplants was determined and was correlated with platelet recovery after intensive chemotherapy in 27 patients. The number of CD34+CD41+ cells correlated significantly better with the time of platelet recovery after PBSC transplantation (r = .83, P = .04) than did the total number of CD34+ cells (r = .55). Statistical analysis produced a threshold value for rapid platelet recovery of 0.34 x 10(6) CD34+CD41+ cells/kg. This study suggests that if performed in the presence of EDTA the flow cytometric measurement of GPIIb/IIIa on CD34+ cells provides the most accurate indication of the platelet reconstitutive capacity of the PBSC transplant. 相似文献
77.
A Akbar JHM Rees G Nyamugunduru MW English DA Spencer PH Weller 《Acta paediatrica (Oslo, Norway : 1992)》1999,88(7):783-785
Hypomagnesaemia in children with cystic fibrosis (CF) is under-recognized. We report a child with CF who developed significant hypomagnesaemia following intravenous (i.v.) treatment with aminoglycosides for exacerbations of Pseudomonas aeruginosa infection. Three additional cases have also been observed. Investigations in two patients have revealed excessive renal loss of magnesium. It is postulated that renal tubular damage secondary to the cumulative effects of repeated courses of aminoglycosides resulted in hypomagnesaemia, and we suggest screening for this problem by monitoring serum magnesium regularly in all patients with CF receiving multiple courses of aminoglycosides. 相似文献
78.
79.
80.
Twenty patients, aged 4 months to 58 years, were evaluated for liver transplantation by duplex sonography, and 15 transplantations were completed; 42 postoperative examinations were performed. Sonographic findings were correlated with seven preoperative and five postoperative angiographic evaluations. Preoperative duplex US findings included tumors, portal vein occlusion, varices, biliary obstruction, and variant vascular anatomy. Postoperative findings included hepatic artery occlusion, portal vein occlusions (one with cavernous transformation), portal vein stenosis, biliary obstruction, intrahepatic and extrahepatic fluid collections, and air in the portal vein due to ischemic bowel. Use of angiography allowed confirmation of the vascular abnormalities and demonstrated evidence of rejection in patients with normal Doppler waveforms. Duplex sonography is a valuable portable technique for evaluating these patients and can be used in triage of patients requiring angiography. 相似文献