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911.
Picherit C Horcajada MN Mathey J Chanteranne B Puel C Lebecque P Davicco MJ Coxam V Barlet JP 《Annals of nutrition & metabolism》2003,47(2):70-77
Some controversy exists in the literature concerning the effects of leptin on bone metabolism. Thus we have compared femoral bone density and biochemical markers of bone metabolism in male and female fatty (leptin-resistant) Zucker rats and their lean homozygous controls at 3 and 6 months of age. At 3 months, no differences concerning total, diaphyseal (cortical bone), and distal metaphyseal (trabecular bone) femoral bone densities, plasma osteocalcin concentrations, and urinary deoxypyridinoline excretion were observed between fatty and lean rats. On the opposite, at 6 months of age, in both males and females, total, diaphyseal, and distal metaphyseal femoral bone densities and plasma osteocalcin concentrations were lower in Zucker than in lean rats. Soybean isoflavone consumption (40 microg/g body weight/day for 90 days, a dose which prevents osteopenia following ovariectomy both in lean Zucker homozygous controls and in Wistar rats) by obese female Zucker rats had no significant effect upon their bone mass. 相似文献
912.
913.
914.
Octogenarians reaching end-stage renal disease: cohort study of decision-making and clinical outcomes 总被引:7,自引:0,他引:7
Joly D Anglicheau D Alberti C Nguyen AT Touam M Grünfeld JP Jungers P 《Journal of the American Society of Nephrology : JASN》2003,14(4):1012-1021
The fate of octogenarians reaching end-stage renal disease (ESRD) is poorly defined, and implicit dialysis rationing may be practiced in this age group. The main objectives of this study were to analyze the characteristics of pre-ESRD octogenarians offered dialysis or not and to identify factors influencing mortality while on dialysis, to improve prognosis assessment and decision-making. In this single-center cohort, 146 consecutive pre-ESRD octogenarians were referred to a nephrology unit over a 12-yr period (1989 to 2000). Main outcome measures were baseline characteristics of patients offered dialysis and conservative therapy and overall and 1-yr survival according to effective treatment. A therapeutic decision was made for 144 patients. Octogenarians who were not proposed dialysis (n = 37) differed from those who were proposed dialysis (n = 107) mainly in terms of social isolation (43.3% versus 14.7%; P = 0.03), late nephrologic referral (51.4% versus 28.9%; P = 0.01), Karnofsky score (55 +/- 18 versus 63 +/- 20; P = 0.03), and diabetic status (22.2% versus 6.5%, P = 0.008). Six patients refused the dialysis proposal. During the 12-yr observation period, 99 patients died (68.7%). Median survival was 28.9 mo (95% CI, 24 to 38) in patients undergoing dialysis, compared with 8.9 mo (95% CI, 4 to 10) in patients treated conservatively (P < 0.0001). In multivariable piecewise Cox analysis, independent predictors of death within 1 yr on dialysis were poor nutritional status, late referral, and functional dependence. Included in a survivor function, these covariates predict groups with low and high 1-yr mortality risk. Beyond 1 yr on dialysis, the only independent predictor of death was the presence of peripheral vascular disease. It is concluded that beside a patient's individual refusal, late referral, social isolation, low functional capacity, and diabetes may have oriented medical decision toward withholding dialysis in a significant proportion of pre-ESRD octogenarians. Although most patients on dialysis experienced a substantial prolongation of life, identification of mortality predictors in this age group should improve the process of decision-making regarding the expected benefit of renal replacement therapy. 相似文献
915.
Barlési F Doddoli C Chetaille B Torre JP Giudicelli R Thomas P Kleisbauer JP Fuentes P 《Interactive Cardiovascular and Thoracic Surgery》2003,2(4):558-562
Regarding persisting controversies about neoadjuvant treatment (NT), we studied the impact of neoadjuvant therapy in daily practice. Patients with stage IIIA-N2 non-small cell lung cancer (NSCLC) resected after NT were eligible. Data on preoperative treatments, surgical procedure, postoperative complications and survival were collected. Overall, 71 (60 men, median age of 60 years) patients met inclusion criteria. All patients received a two-drug platinum-based regimen (median of 2.5 cycles [2-4 cycles]) and 15 (21%) had an associated radiotherapy (20-40 Gy). Nine complete and 27 partial responses were achieved. Surgical procedure principally was a lobectomy (44%), a left (15.5%) or a right (27%) pneumonectomy. Operative mortality was 4.2% while 21 patients (29%) experienced postoperative complications. Median survival was 17 months (95% CI, 13-21 months) with 3- and 5-year survival rates of 24 and 13%, respectively. Five-year survival was worse if postoperative complication occurred (18 versus 0%, p=0.09). Multivariate analysis showed male gender (RR=0.37, 95% CI, 0.16-0.81, p=0.013) and postoperative positive lymph node (RR=2.7, 95% CI, 1.4-5.2, p=0.002) to influence survival. In conclusion, achievement of a clinical and pathological response after NT for stage IIIA-N2 NSCLC patients enables a better survival. More efficient but also less toxic regimens of chemotherapy should be developed regarding its impact on long-term survival. 相似文献
916.
Objective To assess the immediate and late clinical outcome of left anterior descending artery ostial lesions treated with percutaneous coronary intervention.Methods Seventeen patients (6 females and 11 males) treated with percutaneous coronary intervention for ostial left anterior descending artery stenoses have had clinical follow-ups over 12 months. Clinical events were defined as an occurrence of death, myocardial infarction, recurrent angina, and reguiring repeat revascularization (either by angioplasty or by surgery). A matched population treated with coronary bypass surgery was selected based on the similarities in age, left ventricular ejection fraction and the number of diseased vessels. Kaplan-Meier event-free survival curves were generated and the matched comparison was done using the Chi-square test (Mc Neimar method).Results In the catheter-based angioplasty group, the patients’ mean age was 63±8 years. One patient was treated with directional atherectomy plus balloon, 6 with rotational atherectomy plus balloon, 7 with stent and 3 with rotational atherectomy plus stent. Glycoprotein Ⅱb/Ⅲa antagonist was used in 4 cases. Initial procedural success without major complications was achieved in all cases. The mean reference diameter was 2.90±0.48 mm. The minimum lumen diameter increased from 1.05±0.30 mm to 2.40±0.45 mm, and the diameter stenosis decreased from 64%±7% to 8%±13%. During the follow-up period, adverse events reguiring repeat revascularization occurred in 8 patients. The event-free probability was 0.42±0.14 in a two-year period. In a matched population treated with bypass surgery (single mammary graft), only one event occurred, and the difference in event-free survival in two-year period between the two patient groups was significant.Conclusions Percutaneous coronary intervention for left coronary descending artery ostial lesion is technically feasible and safe, leading to an optimal early success rate, but has a higher risk of late restenosis and greater need for repeat revascularization than coronary bypass surgery. 相似文献
917.
Gourion D Goldberger C Bourdel MC Bayle FJ Millet B Olie JP Krebs MO 《Schizophrenia Research》2003,63(1-2):181-187
Markers of vulnerability have been identified in schizophrenia, and among them, neurological soft-signs (NSS) and minor physical anomalies (MPAs) also seem to occur in biological relatives. The similarities of these developmental markers within families may depend on either genetic or non-genetic factors. The aim of the study was to investigate the intra-familial similarities of NSS and MPAs within 18 nuclear families (18 probands with schizophrenia and 36 of their non-psychotic parents). A general linear model showed similarities within families for NSS (intra-class coefficient [ICC] = 0.64; F = 2.6; df = 17.17; p = 0.02) but not for MPAs (ICC = -0.10; F = 0.7; df = 17.17; ns). We thus found a direct evidence for the intra-familial transmission of NSS but not of MPAs, suggesting that this morphological phenotypic trait could be more dependent on epigenetic influences. 相似文献
918.
Positron emission tomography (PET) was used to study the involvement of supraspinal structures in human locomotion. Six right-handed adults were scanned in four conditions while imagining locomotor-related tasks in the first person perspective: Standing (S), Initiating gait (IG), Walking (W) and Walking with obstacles (WO). When these conditions were compared to a rest (control) condition to identify the neural structures involved in the imagination of locomotor-related tasks, the results revealed a common pattern of activations, which included the dorsal premotor cortex and precuneus bilaterally, the left dorsolateral prefrontal cortex, the left inferior parietal lobule, and the right posterior cingulate cortex. Additional areas involving the pre-supplementary motor area (pre-SMA), the precentral gyrus, were activated during conditions that required the imagery of locomotor movements. Further subtractions between the different locomotor conditions were then carried out to determine the cerebral regions associated with the simulation of increasingly complex locomotor functions. These analyses revealed increases in rCBF activity in the left cuneus and left caudate when the W condition was compared to the IG condition, suggesting that the basal ganglia plays a role in locomotor movements that are automatic in nature. Finally, subtraction of the W from the WO condition yielded increases in activity in the precuneus bilaterally, the left SMA, the right parietal inferior cortex and the left parahippocampal gyrus. Altogether, the present findings suggest that higher brain centers become progressively engaged when demands of locomotor tasks require increasing cognitive and sensory information processing. 相似文献
919.
Wnt-frizzled signaling in neural crest formation 总被引:4,自引:0,他引:4
920.
Kubisch C Schoser BG von Düring M Betz RC Goebel HH Zahn S Ehrbrecht A Aasly J Schroers A Popovic N Lochmüller H Schröder JM Brüning T Malin JP Fricke B Meinck HM Torbergsen T Engels H Voss B Vorgerd M 《Annals of neurology》2003,53(4):512-520
Heterozygous missense mutations in the caveolin-3 gene (CAV3) cause different muscle disorders. Most patients with CAV3 alterations present with rippling muscle disease (RMD) characterized by signs of increased muscle irritability without muscle weakness. In some patients, CAV3 mutations underlie the progressive limb-girdle muscular dystrophy type 1C (LGMD1C). Here, we report two unrelated patients with novel homozygous mutations (L86P and A92T) in CAV3. Both presented with a more severe clinical phenotype than usually seen in RMD. Immunohistochemical and immunoblot analyses of muscle biopsies showed a strong reduction of caveolin-3 in both homozygous RMD patients similar to the findings in heterozygous RMD. Electron microscopy studies showed a nearly complete absence of caveolae in the sarcolemma in all RMD patients analyzed. Additional plasma membrane irregularities (small plasmalemmal discontinuities, subsarcolemmal vacuoles, abnormal papillary projections) were more pronounced in homozygous than in heterozygous RMD patients. A stronger activation of nitric oxide synthase was observed in both homozygous patients compared with heterozygous RMD. Like in LGMD1C, dysferlin immunoreactivity is reduced in RMD but more pronounced in homozygous as compared with heterozygous RMD. Thus, we further extend the phenotypic variability of muscle caveolinopathies by identification of a severe form of RMD associated with homozygous CAV3 mutations. 相似文献