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21.
Andrew E. Springer Kayan Lewis Steven H. Kelder Maria E. Fernandez Cristina S. Barroso Deanna M. Hoelscher 《Journal of immigrant and minority health / Center for Minority Public Health》2010,12(5):769-780
Research on physical activity (PA) by level of acculturation in Hispanic children is limited and findings have been mixed.
We examined PA participation by primary language used with parents in a representative sample of 4th, 8th, and 11th grade
Texas public school students. Mixed-effects regression models were conducted using cross-sectional data from the 2004–2005
School Physical Activity and Nutrition Study (n = 22,049). Self-reported PA was compared among three language-ethnic groups: Spanish-Hispanic (SH) (referent); English-Hispanic
(EH); and English-Other (EO). EH and/or EO girls were generally between 1.25 and 2.58 [OR] times more likely to participate in PA across grade levels,
with the largest differences found for school sports in 8th grade girls. EH and EO 8th grade boys were 1.71 (CI: 1.40, 2.10)
and 2.06 (CI: 1.68, 2.51) times, respectively, more likely to participate in school sports. Findings indicate important disparities
in Spanish-speaking Hispanic children’s PA participation. 相似文献
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26.
Plasma levels and vascular effects of vasopressin in patients undergoing coronary artery bypass grafting. 总被引:1,自引:0,他引:1
Susana Novella Ana Cristina Martínez Rosa María Pagán Medardo Hernández Albino García-Sacristán Angel González-Pinto José María González-Santos Sara Benedito 《European journal of cardio-thoracic surgery》2007,32(1):69-76
OBJECTIVE: Recent studies have suggested that endogenous vasopressin (AVP) acts as a spasmogen during coronary artery bypass grafting (CABG). Given that AVP could induce vasospasm in the grafted vessel, we assessed the release of this peptide during and after CABG, and explored ways of counteracting its contractile effect on the internal mammary artery (IMA). METHODS: Plasma levels of AVP were determined by radioimmunoassay in 16 patients before, during and after CABG. Using isometric force recording techniques, we also investigated the mechanisms involved in the contractile effect of AVP in ring preparations of IMA specimens taken from 95 patients. RESULTS: Plasma AVP levels peaked after the start of cardiopulmonary bypass (CPB) and correlated well with serum osmolality (Pearson's r=0.9490; P<0.0001; n=16). An inverse correlation was observed between plasma AVP levels recorded at this stage and the maximal contraction induced in vitro by AVP in vascular rings from the same patients (Pearson's r=-0.6968; P<0.01; n=16). No change in the AVP response was produced by endothelium removal, exposure to the NO precursor (3 x 10(-4)M L-arginine), inhibition of nitric oxide (NO) synthase (3 x 10(-5) M L-NAME) or soluble guanylate cyclase (3 x 10(-6) M 1H-[1,2,4]oxadiazol [4,3,-alpha]quinoxalin-1-one (ODQ)), removal of the superoxide anion (100 U/ml superoxide dismutase (SOD) plus 1200 U/ml catalase) or hydroxyl radical (10(-4) M deferoxamine), or specific alpha1 - (10(-6) M prazosin) or endothelin (10(-5) M bosentan) receptor antagonism. In contrast, adenylate cyclase activation (3 x 10(-8) M forskolin) reduced the contractile response to AVP, while prostanoid synthesis (3 x 10(-6) M indomethacin) inhibition and blockade of Ca2+ -activated potassium channels (KCa) (10(-3) M tetraethylammonium (TEA)) enhanced AVP contraction. Age, gender and smoking also modified the AVP response. CONCLUSION: Our findings suggest a role for AVP as a modulator of vascular tone in human IMA. The effect of AVP is dependent on prostanoids and Ca2+ -activated K+ channels, so its dysfunction in pathophysiological cardiovascular processes could mean that AVP, among other factors, produces vasospasm in IMA grafts. 相似文献
27.
Familial 46,XX gonadal dysgenesis 总被引:1,自引:0,他引:1
J A Portuondo J L Neyro J A Benito A de los Rios A Barral 《International journal of fertility》1987,32(1):56-58
Two sisters, ages 18 and 25, presented with primary amenorrhea and underwent clinical, hormonal, cytogenetic, and pathologic evaluation. Both were of normal stature and lacking of somatic stigmata. Both patients had normal 46,XX karyotype on peripheral blood. Streak gonads were seen in both patients and a rather scanty number of primordial follicles was found in one patient. FSH, LH, and urinary estrogens were consistent with streak gonad syndrome. Autosomal recessive inheritance has been suggested in familial aggregates with XX gonadal dysgenesis. 相似文献
28.
To evaluate the effects of irradiation on heterotopically placed vascularized knee isografts, a single dose of 10 Gy of total-body irradiation was given to Lewis donor rats. Irradiation was delivered either 2 or 6 days prior to harvesting or subsequent transplantation, and evaluated at 1, 2, and 4 weeks after grafting. Irradiation caused endothelial depopulation of the graft artery, although vascular pedicle patency was maintained throughout the study. Bone graft viability and mineralization were normal. Dramatic changes in the bone marrow were seen that included an increase of its fat content (P less than 0.001), and a concomitant decrease in bone marrow-derived immunocompetent cells. These changes were more prominent in recipients of grafts from day -6 irradiated donor rats. Total-body irradiation did not prejudice the use of vascularized bone grafts, and exhibited an associated immunosuppresant effect over the vascular endothelium and bone marrow. This may be a further rational conditioning procedure to avoid recipient manipulation in vascularized bone allotransplantation. 相似文献
29.
Juan J. Muoz Cristina Roca Jos L. Santos Miguel Arroyo Rafael E. de Salamanca 《Basic & clinical pharmacology & toxicology》1993,73(4):189-191
Two alternatives for the treatment of lead intoxication, administration of zinc or a thiol donor, S-adenosyl-L-methionine (SAM), were analysed. Rats were exposed to lead (Pb)-acetate (60 mg/1) in drinking water during 90 days; one group also received SO4Zn in water (40 mg/l), while another received both Pb and SAM (5 mg/24 hr intraperitoneally. Erythrocytic δ-aminolaevulinic dehydratase (ALA-D) activity was significantly reduced (P<0.001) both in rats receiving Pb alone and in rats receiving Pb and each of the other two treatments. The high erythrocytic uroporphyrinogen synthetase (URO-S) activity noticed in Pb administered rats, was significantly (P< 0.001) reduced in animals treated either with zinc or with SAM. Hepatic ALA-D activity tended to decrease while renal enzyme activity was not modified by the low level Pb exposure used in this work. Interestingly, SAM treated rats in both tissues exhibited significantly (P<0.01) higher activities of the enzyme. It is argued that SAM treatment causes a surplus of thiols that allows the full expression of ALA-D catalytic activity. 相似文献
30.
Arnold Criel Gregor Verhoef Robert Vlietinck Cristina Mecucci Johan Billiet Lucienne Michaux Peter Meeus ries Louwagie Angeline Van Orshoven Achiel Van Hoof Mark Boogaerts Herman Van den Berghe & Chris De Wolf-Peeters 《British journal of haematology》1997,97(2):383-391
We analysed a group of 390 patients, diagnosed with chronic lymphocytic leukaemia (CLL). Cases were subclassified as morphologically typical and atypical CLL according to the criteria of the FAB proposal. Typical CLL cases were mostly diagnosed at a low-risk stage (Binet A/Rai 0), required no immediate treatment and expected a long survival; atypical CLL cases mostly presented at a more advanced risk stage (Binet B/Rai I–II), usually required immediate treatment and their survival was shorter. Moreover, clinical staging was of prognostic significance in typical but not in atypical cases. In typical CLL, del(11q) was the most common chromosomal abnormality (21%) whereas in atypical CLL trisomy 12 was found in about 65% of the cases documented with an abnormal karyotype. Although chromosomal abnormalities were associated with a poor survival in typical CLL, they are of no prognostic significance in atypical CLL. Based on these data, we conclude that subtyping CLL by morphology enables the identification of two groups of cases, each characterized by a specific clinical presentation, different cytogenetic abnormalities and prognostic parameters. We speculate that these two groups may represent two related, but different, diseases with different prognostic parameters and a different survival. 相似文献