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排序方式: 共有10000条查询结果,搜索用时 31 毫秒
41.
Volume control associated with better cardiac function in long-term peritoneal dialysis patients. 总被引:4,自引:0,他引:4
Gulay A?ci Mehmet Ozkahya Soner Duman Huseyin Toz Sinan Erten Ercan Ok 《Peritoneal dialysis international》2006,26(1):85-88
BACKGROUND: This study was undertaken to investigate the effect of long-term blood pressure (BP) reduction, achieved with salt restriction and strict volume control, on frequency and regression of left ventricular hypertrophy (LVH) in long-term peritoneal dialysis (PD) patients. METHODS: 56 patients who had been treated for more than 2 years under our care were enrolled. After echocardiographic (Echo) evaluation, 46 patients were included in the follow-up study. In our unit, we aim to keep patients' BP below 130/85 mmHg and cardiothoracic index below 0.50. To reach these targets, moderate salt restriction is advised, and if necessary, hypertonic PD solutions are used. Echo was performed at the beginning of the study (after a mean period of 36 months on PD) and at the end of the prospective follow-up period (24 months later). RESULTS: At the time of the first Echo, LVH was detected in only 8 (21%) patients. Residual urine volume was significantly decreased compared to data taken when they first started PD (658 +/- 795 vs 236 +/- 307 mL/day). Mean left ventricular mass index (LVMI) was 107 +/- 26.5 g/m2. LVMI was significantly decreased at the end of the follow-up in patients who had LVH at baseline. No LVH developed in patients who had normal LVMI at baseline. CONCLUSION: Our results indicate that control of hypertension is possible when extracellular fluid volume is kept under control using hypertonic PD solutions in case of recruitment in addition to salt restriction in long-term PD patients. Sustained normovolemia is associated with low incidence and regression of LVH. 相似文献
42.
M Müller J Grunewald C Olgart H?glund B Dahlén A Eklund H Stridh 《The European respiratory journal》2006,28(3):513-522
The increased number of lymphocytes in airways during an asthmatic response is believed to be the result of increased recruitment of these cells. However, it is possible that a decreased apoptotic rate could also contribute to the increased number. The aim of the present study was to investigate whether allergen airway provocation influences the apoptotic phenotype of lung and peripheral blood lymphocytes (PBL) in subjects with atopic asthma. Bronchoalveolar lavage (BAL) lymphocytes and PBL from 12 asthmatic subjects previously challenged with allergen (n = 7) or saline (n = 5) were exposed to the apoptotic stimulus tributyltin (TBT) in vitro and assayed for apoptosis. Airway allergen provocation resulted in decreased sensitivity of BAL lymphocytes to TBT-induced apoptosis, with 42.2% (range 33.9-62.5%) apoptotic cells before challenge versus 23.5% (range 15.3-42.4%) after challenge, while PBL were unaffected. The increased apoptosis resistance correlated with higher numbers of Bcl-2-expressing lymphocytes. Interestingly, baseline caspase-3-like activity was significantly elevated in viable BAL lymphocytes compared with viable PBL, and was unaltered by allergen exposure. In conclusion, allergen inhalation renders bronchoalveolar lavage lymphocytes more resistant to apoptosis while peripheral blood lymphocytes were not influenced at all, indicating that the apoptotic phenotype of airway lymphocytes may play a role in asthmatic inflammation. 相似文献
43.
Sergue? O Fetissov Jarmila Hallman Ida Nilsson Ann-Kari Lefvert Lars Oreland Tomas H?kfelt 《Neuropsychopharmacology》2006,60(8):799-802
BACKGROUND: Altered stress response is characteristic for subjects with abnormal aggressive and antisocial behavior, but the underlying biological mechanisms are unclear. We hypothesized that autoantibodies (autoAbs) directed against several stress-related neurohormones may exist in aggressive subjects. METHODS: Using enzyme-linked immunosorbent assay, we studied whether autoAbs directed against corticotropin (ACTH), alpha-melanocyte-stimulating hormone (alpha-MSH), oxytocin, and vasopressin are present in serum of male subjects with conduct disorder and prisoners with history of violence. Healthy blood donors served as control subjects. RESULTS: Both conduct disorder and prisoners groups displayed strongly increased levels of ACTH-reactive immunoglobulin G (IgG) and immunoglobulin M (IgM) autoAbs compared with control subjects. Levels of oxytocin-reactive IgM autoAbs were slightly increased in both groups of aggressive subjects, whereas levels of vasopressin-reactive IgG and IgM autoAbs were lower only in conduct disorder. No differences in the levels of alpha-MSH-reactive autoAbs were found between aggressive and control subjects. CONCLUSIONS: High levels of ACTH-reactive autoAbs as well as altered levels of oxytocin- and vasopressin-reactive autoAbs found in aggressive subjects may interfere with the neuroendocrine mechanisms of stress and motivated behavior. Our data suggest a new biological mechanism of human aggressive behavior that involves autoAbs directed against several stress-related neurohormones. 相似文献
44.
Stephen J Glatt Erik G J?nsson 《American journal of medical genetics. Part B, Neuropsychiatric genetics》2006,(2):149-154
Previously we derived independent estimates of the effect of the dopamine D2 receptor (DRD2) Ser311Cys polymorphism on risk for schizophrenia using fixed- and random-effects meta-analyses. Both analyses identified a significant association between the Cys allele and schizophrenia, but neither included all available data. Furthermore, genotype data were not evaluated in either analysis, thus precluding any determination of the mode of inheritance. The present study was conducted to resolve discrepancies between the existing meta-analyses, and provide more comprehensive and accurate estimates of the nature and magnitude of the influence of the Ser311Cys polymorphism on risk for schizophrenia. All discrepancies between the two sets of previously meta-analyzed studies were identified and resolved to the mutual satisfaction of the authors, and the final dataset was analyzed independently by fixed- and random-effects meta-analyses. A total of 27 samples, comprising 3,707 schizophrenia patients and 5,363 control subjects, were included in the analyses of allelic association, while smaller numbers of studies and subjects were included in each of the genotypic association analyses. A significant effect of the Cys allele was observed under both fixed-effects (odds ratio [OR] = 1.4; P = 0.002) and random-effects (OR = 1.4; P = 0.007) models. Cys/Ser heterozygotes were at elevated risk for schizophrenia when compared to Ser/Ser homozygotes (fixed- and random-effects OR = 1.4, p(s) or= 0.948). There was no evidence of heterogeneity, excessive influence of any single study, or publication bias in any of the analyses, suggesting that the effect of this DRD2 polymorphism on schizophrenia risk is reliable and uniform across populations, and our estimates of its magnitude are robust and accurate. 相似文献
45.
S Balzer D T Schneider M B Bernbeck M J?ger O Mils J Schaper R Willers R Krauspe U G?bel R Wessalowski 《International journal of hyperthermia》2006,22(6):451-461
PURPOSE: In children with locally advanced or recurrent malignant tumours, prognosis can be improved by regional deep hyperthermia (RHT) in combination with platin-based chemotherapy. However, because of the increasing number of patients that achieve long-time remission with this therapy, it is necessary to evaluate long-term sequelae of thermochemotherapy. During the years 1993-2004 one has observed avascular osteonecrosis (AON) of the femoral head after RHT in seven children with pelvic germ cell tumours or rhabdomyosarcomas. METHODS: Although AON may develop in patients with malignancies treated with chemo- or radiotherapy alone, RHT might nevertheless contribute to the occurrence of AON. In order to determine potential risk factors for AON after RHT, this study analysed the relationship of AON to the patient's age, medical history and treatment parameters such as thermal dose equivalent and power output. RESULTS AND CONCLUSIONS: In the present study AON was associated with young age as well as intensity of hyperthermia indicated by high power levels that exceed 20 W per kg body weight and/or application of eight or more heat sessions as well as additional radiotherapy. Based on this observation, it was assumed that an optimized three dimensional thermal field modelling may be helpful to avoid hazardous temperatures in the femoral heads during RHT treatment and to reduce AON of the femoral heads. 相似文献
46.
Bifid mandibular canal. 总被引:1,自引:0,他引:1
PURPOSE: To determine the incidence and characteristics of bifid mandibular canals. METHODS: A retrospective study was performed using panoramic radiographs of 2012 patients subjected to dental treatment in the Dental Clinic of the Valencia University Dental School (Valencia, Spain) between 1996 and 1999. The goal was to investigate the presence of double mandibular canals. RESULTS: The extraoral panoramic radiographs revealed a total of 7 images suggestive of bifid canals. Mandibular computed tomography revealed the existence of this anatomic variant in 2 of 3 patients. An analysis was performed on the incidence of this type of image in extraoral panoramic radiography, its possible interpretations, and the clinical implications of bifid mandibular canals. CONCLUSIONS: In this study, 0.35% of canals were bifid. All cases were in women. 相似文献
47.
Victor Aboyans Louis Labrousse Philippe Lacroix Jér?me Guilloux Seifeddine Sekkal Alexandre Le Guyader Elisabeth Cornu Marc Laskar 《European journal of cardio-thoracic surgery》2006,30(2):300-304
BACKGROUND: Despite major improvement in surgical techniques and intensive care management, stroke remains one of the most devastating complications of coronary artery bypass grafting (CABG). We aimed to determine factors predicting the occurrence of stroke during CABG. A special interest was focused on preoperative therapies. METHODS: We prospectively enrolled 810 consecutive candidates for CABG alone in a specific database, including all pre- and perioperative data (history, clinical, therapeutic, cardiac catheterization, surgical and intensive care data). Univariate tests and then multiple logistic regression analysis were used to determine independent predictive factors. RESULTS: During the first postoperative month, stroke occurred in 11 cases and transient ischemic attack (TIA) in 4 additive cases (cumulative rate: 1.85%). After the multivariate analysis, the following factors remained significant (p<0.05) in the predictive model, with corresponding odds ratios between brackets: redo cardiac surgery (7.45), unstable cardiac status (4.74), past history of cerebrovascular disease (4.14), past history of peripheral arterial disease (3.55), whereas the presence of preoperative statins was protective (0.24, 95% IC: 0.07-0.78). The addition of perioperative data (aortic calcification, postoperative arrhythmia, on/off-pump surgery) did not change the final predictive model. CONCLUSION: To our knowledge, this is the first real-world observational report highlighting the interest of statins for the prevention of stroke in the very special situation of CABG. Even though according to randomized trials coronary patients have a benefit from these drugs, a special level of interest should be directed towards those presenting the above-mentioned risk factors. 相似文献
48.
Stability of transverse expansion in the mandibular arch. 总被引:1,自引:0,他引:1
Jeffrey A Housley Ram S Nanda G Fr?ns Currier Dale E McCune 《American journal of orthodontics and dentofacial orthopedics》2003,124(3):288-293
This was a retrospective, longitudinal cephalometric and cast study of 29 white patients at pretreatment, posttreatment, and an average of 6 years 3 months postretention. The goal was to assess changes with treatment and retention with the expanding mandibular lingual arch appliance in conjunction with fixed edgewise treatment. Seven mandibular cast measurements were assessed, including arch crowding, arch perimeter, arch length, and arch width at the permanent canines, first premolars, second premolars, and first molars. Cephalometric radiographs were digitized, and 16 cephalometric measurements were made. Repeated-measures analysis of variance and 2-sample t tests were used to determine statistically significant changes. It was found that the expanding lingual arch used for less than 6 months with the mandibular fixed edgewise appliance caused an increase in both the transverse and sagittal dimensions of the mandibular dental arch. Transverse expansion was more stable in the posterior region of the mandibular dental arch than in the anterior region. Mandibular intercanine width increase could be maintained only by fixed retention. Although the maxillary and mandibular incisors were advanced and proclined, lip protrusion did not occur. 相似文献
49.
BCR-ABL activity and its response to drugs can be determined in CD34+ CML stem cells by CrkL phosphorylation status using flow cytometry. 总被引:2,自引:0,他引:2
A Hamilton L Elrick S Myssina M Copland H J?rgensen J V Melo T Holyoake 《Leukemia》2006,20(6):1035-1039
In chronic myeloid leukaemia, CD34(+) stem/progenitor cells appear resistant to imatinib mesylate (IM) in vitro and in vivo. To investigate the underlying mechanism(s) of IM resistance, it is essential to quantify Bcr-Abl kinase status at the stem cell level. We developed a flow cytometry method to measure CrkL phosphorylation (P-CrkL) in samples with <10(4) cells. The method was first validated in wild-type (K562) and mutant (BAF3) BCR-ABL(+) as well as BCR-ABL(-) (HL60) cell lines. In response to increasing IM concentration, there was a linear reduction in P-CrkL, which was Bcr-Abl specific and correlated with known resistance. The results were comparable to those from Western blotting. The method also proved to be reproducible with small samples of normal and Ph(+) CD34(+) cells and was able to discriminate between Ph(-), sensitive and resistant Ph(+) cells. This assay should now enable investigators to unravel the mechanism(s) of IM resistance in stem cells. 相似文献
50.