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991.
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Black HR Elliott WJ Neaton JD Grandits G Grambsch P Grimm RH Hansson L Lacoucière Y Muller J Sleight P Weber MA White WB Williams G Wittes J Zanchetti A Fakouhi TD Anders RJ 《Hypertension》2001,37(1):12-18
-Blood pressure (BP) control rates around the world are suboptimal. Part 2 of the National Health and Nutrition Educational Survey (NHANES) III indicates that only 27.4% of hypertensive Americans aged 18 to 74 years have a BP of <140/90 mm Hg. We wanted to assess BP control during the first 2 years and to describe the baseline characteristics of patients enrolled in the Controlled ONset Verapamil INvestigation of Cardiovascular Endpoints (CONVINCE) Study, an international clinical trial that compares outcomes in hypertensive patients randomized to initial treatment with either controlled-onset extended-release verapamil or the investigator's choice of atenolol or hydrochlorothiazide. At randomization, BP was <140/90 mm Hg in only 20.3% of the 16 602 subjects (average+/-SD age 65.6+/-7.4 years; 56% women, 84% white/7% black/7% Hispanic). The average BP at enrollment was 148/85 mm Hg for patients taking BP medications (n=13 879) and 161/94 mm Hg for previously untreated patients (n=2723). After medication titration, with a transtelephonic computer that recommended an increase in the dose or number of antihypertensive agents whenever the BP was 140/90 mm Hg, 84.8% of the subjects attained the goal BP. During 2 years of treatment, BP control was maintained in 67% to 69% of the subjects (69% to 71% for systolic BP of <140 mm Hg and 90% for diastolic BP of <90 mm Hg). These data suggest that the control of systolic BP is more difficult than the control of diastolic BP. The US national goal of having 50% of hypertensives with a BP of <140/90 mm Hg may be achievable if a forced titration strategy is used. Interested investigators, free care and medications, and well-educated subjects may make the attainment of such a goal easier in the CONVINCE study than in the general population. 相似文献
994.
995.
B. Beaufrère M. Beylot C. Metz A. Ruitton R. François J. P. Riou R. Mornex 《Diabetologia》1988,31(8):607-611
Summary In order to reassess the role of growth hormone in the dawn phenomenon, we studied eight C-peptide negative diabetic adolescents, who are likely to exhibit important nocturnal growth hormone surges. The insulin infusion rate necessary to maintain euglycaemia was predetermined in each patient from 22.00 hours to 01.00 hours, and then kept constant until 08.00 hours resulting in stable free insulin levels. Blood glucose rose from 4.3±0.7 mmol/l at 01.00 hours to 7.1±1.1 mmol/l at 08.00 hours (p<0.01) secondary to an increased hepatic glucose production. All the subjects presented an important growth hormone secretion, ranging from 20 to 66 ng/ml (peak values) and from 3619 to 8621 ng·min· ml–1 (areas under the curve). The insulin infusion rate selected for each patient was positively correlated with the nocturnal growth hormone secretion (area under the curve) (r=0.87, p<0.01). On the other hand, there was no relationship between the nocturnal growth hormone secretion and the magnitude of the early morning blood glucose rise (r=–0.48, p>0.2). We conclude that, in Type 1 (insulin-dependent) diabetic adolescents, the dawn phenomenon exists but is moderate despite important growth hormone surges; the nocturnal growth hormone secretion influences the nocturnal insulin requirements but not the dawn phenomenon itself, if insulinisation is adequate. 相似文献
996.
Cazals-Hatem D Rebouissou S Bioulac-Sage P Bluteau O Blanché H Franco D Monges G Belghiti J Sa Cunha A Laurent-Puig P Degott C Zucman-Rossi J 《Journal of hepatology》2004,41(2):292-298
BACKGROUND/AIMS: Combined hepatocellular-cholangiocarcinoma (HCC-CC) show dual hepatocellular and biliary epithelial differentiation. To better understand the relations between cholangiocarcinoma (CC), HCC-CC and hepatocellular carcinoma (HCC), we screened for genetic alterations. METHODS: A series of nine CC, 15 HCC-CC and three separated HCC and CC lesions ('collision tumors') were screened for loss of heterozygosity (LOH) using 400 microsatellite markers and for p53 and beta-catenin mutations. A comparison with a previously characterized series of 137 HCC was performed. RESULTS: In six cases of CC and HCC-CC, we identified TP53 gene mutations. A CTNNB1/beta-catenin was identified in two patients presenting collision tumors, but no mutations were found in CC or in HCC-CC. A high level of chromosome instability in both CC and HCC-CC was found. Recurrent specific LOH were identified at 3p and 14q in more than 50% of the CC and the HCC-CC cases, whereas these chromosomal regions were deleted in less than 10% of the HCC cases (P<10(-5)). Minimal common regions of deletion (MCRD) were defined at 3p24-p14 and 14q24-q32, respectively. CONCLUSIONS: These results suggest that combined HCC-CC are genetically closer to CC than HCC and common carcinogenesis pathways may be altered in HCC-CC and CC. 相似文献
997.
Comparison of human skeletal myoblasts and bone marrow-derived CD133+ progenitors for the repair of infarcted myocardium 总被引:5,自引:0,他引:5
Agbulut O Vandervelde S Al Attar N Larghero J Ghostine S Léobon B Robidel E Borsani P Le Lorc'h M Bissery A Chomienne C Bruneval P Marolleau JP Vilquin JT Hagège A Samuel JL Menasché P 《Journal of the American College of Cardiology》2004,44(2):458-463
OBJECTIVES: The present study was designed as a face-to-face functional comparison of human skeletal myoblasts (SMs) and CD133(+) bone marrow-derived hematopoietic progenitors in an animal model of semichronic myocardial infarction. BACKGROUND: Compared with SMs, bone marrow-derived cells have the advantage of plasticity and might more effectively regenerate ischemic cardiac tissue. However, few data exist on the comparative efficacy of these two cell types in semichronic infarcts. METHODS: A myocardial infarction was created by coronary ligation in 32 nude rats. Ten days later, rats received in-scar injections of human SMs, CD133(+) progenitors, or culture medium. Left ventricular function was assessed before and one month after transplantation by echocardiography and pressure-volume loops. Immunofluorescence, polymerase chain reaction, and in situ hybridization were used to detect cells grafted in the hearts. RESULTS: One month after transplantation, left ventricular ejection fraction decreased by 8 +/- 4% in controls, whereas it increased by 7 +/- 3% in CD133(+)-grafted hearts (p = 0.0015 vs. controls) and further by 15 +/- 5% in SM-treated hearts (p = 0.008 vs. controls). Systolic indices yielded by pressure-volume loops paralleled these data. Engrafted myotubes were identified in all SM-treated hearts by immunofluorescence, whereas in CD133(+)-grafted hearts, few human cells were only detected by polymerase chain reaction. CONCLUSIONS: In the setting of postinfarction scars, the transplantation of bone marrow-derived CD133(+) progenitors improves cardiac function, but this benefit is not superior to that afforded by myogenic cells. 相似文献
998.
999.
Analysis of TCR,pT alpha,and RAG-1 in T-acute lymphoblastic leukemias improves understanding of early human T-lymphoid lineage commitment 总被引:3,自引:4,他引:3
Asnafi V Beldjord K Boulanger E Comba B Le Tutour P Estienne MH Davi F Landman-Parker J Quartier P Buzyn A Delabesse E Valensi F Macintyre E 《Blood》2003,101(7):2693-2703
1000.
Interactions between chromosomes, microfilaments and microtubules revealed by the study of small GTPases in a big cell, the vertebrate oocyte 总被引:1,自引:0,他引:1
Meiotic divisions during oogenesis in higher eukaryotes are extremely asymmetric giving rise to one gamete, the oocyte, and two polar bodies. In most species, this asymmetric partitioning relies on the eccentric positioning of meiotic spindles. Recent work performed in mouse and frog oocytes has suggested the involvement of small GTPases, such as Cdc42, Rac and Ran both in the control of spindle organization and positioning. The present review summarizes these findings that shed light on the molecular mechanisms by which small GTPases control asymmetric cell divisions in vertebrate oocytes. 相似文献