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31.
Personalized feedback and a financial incentive, developed from an intrinsic/extrinsic motivation framework, were evaluated as adjuncts to self-help materials for smoking cessation. Ss (N = 1,217) were randomized to 4 treatment groups and were followed up at 3 and 12 months. Consistent with hypotheses derived from the motivation framework, the financial incentive increased the use of self-help materials, did not increase cessation rates among program users, and was associated with higher relapse rates among those who did manage to quit. The personalized feedback increased both smoking cessation and use of the materials 3 months after distribution of the materials. Continuous abstinence (abstinence at 3 and 12 months) in the group that received the personalized feedback alone was twice the rate of the other groups.  相似文献   
32.
With increasing numbers of primary anterior cruciate ligament reconstruction, the incidence of unsatisfactory results and graft failures will increase. The goals of revision reconstruction are similar to those of primary reconstruction and include stabilization of the knee, prevention of secondary degenerative changes, and recovery of knee function. Besides the recurrent tear there are specific technical failures, such as tunnel malplacement and unrecognized associated ligamentous pathologies, which might lead to graft failure. Thus, preoperative planning includes a detailed analysis of failure mechanisms by thorough preoperative history taking, comprehensive physical examination, and appropriate radiographic evaluation. The treatment algorithm addresses issues of hardware removal, need for a staged procedure or concomitant surgery, graft source, tunnel placement, and graft fixation. Correct placement of tunnels and graft fixation are the essential surgical steps, which might also influence graft selection. Successful revision ACL surgery requires a motivated and compliant patient and an experienced surgeon who is proficient in a variety of different surgical techniques. However, since clinical outcome is reported to be inferior in revision compared to primary ACL reconstruction the importance of counseling the patient preoperatively regarding less satisfactory results than in most primary ACL reconstructions must be emphasized. This article describes indications, analysis and surgical procedures for revision anterior cruciate ligament reconstruction.  相似文献   
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BACKGROUND: The diagnosis of analgesic nephropathy has improved significantly with modern imaging techniques. We reviewed a large portion of the Hungarian dialysis population to obtain additional insight into the problem. METHODS: Twenty-two participating dialysis units enrolled 1400 patients on renal replacement therapy between 1 January 1995 and 1 January 1998. Patients with no known aetiology (n = 284) were interviewed and studied with renal imaging. We assessed the presence of decreased renal mass combined with either bumpy contours, papillary calcification, or both. The subjects studied were interrogated extensively. RESULTS: Our survey suggested analgesic nephropathy in 47 of 1400 patients (3.3%), 3-fold higher than the EDTA database estimate for Hungary. The analgesics most commonly abused were phenacetin-containing mixtures. The driving symptoms were mainly headache and joint pain. Cardiovascular complications were more common than in the rest of the dialysis population, independent of smoking and lipid values (P<0.01). CONCLUSIONS: Phenacetin should be banned. Our study results support the need for longitudinal cohort and case-control studies in Hungary.  相似文献   
35.
Endothelial progenitor cells (EPC) are involved in endothelial repair and maintenance. Dysfunction of EPC may contribute to accelerated arteriosclerosis in chronic kidney disease. Kidney transplantation (KTx) improves both survival and endothelial function of dialysis patients. In a prospective study, we tested to which extent KTx changes EPC biology. We studied number and function (migratory activity, adhesion to extracellular matrix proteins and to mature endothelial cells [EC]) of EPC in 20 patients during dialysis and 3, 6, 9 and 12 months after KTx. Twenty-two healthy volunteers served as matched controls. Circulating precursor populations were measured by flow cytometric analysis. Cytokines relevant for EPC mobilization were monitored. Compared to the dialysis state, KTx increased the migration of EPC to approximately 2-fold. Adhesion to fibronectin and to collagen type IV was significantly increased after KTx. An improved adhesion rate of EPC to mature EC was observed. The number of EPC decreased. The amount of precursor populations showed no difference compared to the pretransplant state. Our study shows an improved function of EPC after KTx. This finding indicates an improved potential for endothelial repair which in turn may contribute to enhanced endothelial function and reduced cardiovascular morbidity after KTx.  相似文献   
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Pathways and enzymes of fatty acid synthase-mediated, long-even-chain (generally C16-C20) fatty acid synthesis are well studied, and general metabolism involved in short-chain (C4-C7) fatty acid biosynthesis is also understood. In contrast, mechanisms of medium-chain (C8-C14) fatty acid synthesis are unclear. Recent work suggests involvement of chain-elongation-terminating thioesterases in medium-chain fatty acid formation in oilseeds and animals. We have shown that iso- and anteiso-branched and straight, odd- and even-length, short-chain fatty acids esterified in plant-trichome-gland-produced sucrose esters are synthesized by using carbon skeletons provided by modified branched-chain amino acid metabolism/catabolism. The principal enzymes involved are those catalyzing leucine biosynthesis in all organisms and those leading to short-chain alcohols in mutant yeasts and alkyl acids in Clostridium species (products often serving as mammalian pheromones). Here we provide evidence that C10-C12 straight medium-chain and C10-C12 branched medium-chain acyl acids of tomato, C6-C8 straight-chain acyl acids of Petunia, and C6 and C8 branched acyl acids of Nicotiana glutinosa are formed by alpha-ketoacid elongation without participation of fatty acid synthase-mediated reactions or -independent thioesterases. This different metabolism suggests greater integration of amino acid and fatty acid metabolism than previously considered and provides other avenues to study and manipulate not only straight even-length but also odd- and even-length straight and branched medium-chain fatty acid biosynthesis.  相似文献   
38.
MDL74270 (6-acetyloxy-3,4-dihydro-N,N,N,2,5,7, 8-heptamethyl-2H-1-benzopyran-2-ethanaminium, 4-methylbenzenesulfonate) is a quaternary amine analogue of alpha-tocopherol with free radical scavenger properties. Rats were injected iv with [14C]MDL74270 (0.91 mg/kg), and whole blood and heart tissue were sampled. Five min after drug, the heart tissue/blood ratio (T/B) of radioactivity was 3.5, whereas at 1 hr it was 20.1 and remained at this value up to at least 6 hr. After iv administration the t 1/2 of radioactivity in blood was 6.3 hr, but po blood levels could not be quantified. The 0- to 96-hr urinary elimination of radioactivity was 39.9 +/- 5.7% of the dose after iv and only 1.2 +/- 0.4% after po administration, conversely, 44.7 +/- 5.2% was excreted in feces after iv and 79.1 +/- 17.4% after po administration. These results confirmed poor oral absorption of the compound. Tissue distribution of [14C]MDL74270 was compared with that of its tertiary amine analogue [14C]MDL74366 in rat heart, skeletal muscle, brain, and whole blood, after iv administration (1 mg/kg). The heart T/B was above 20, 1-6 hr after [14C]MDL74270, whereas it was less than 2 after [14C]MDL74366. Over the 1- to 6-hr time interval, skeletal muscle T/B varied from 1.8 to 5 compared with 1.5 to 0.6 for [14C] MDL74366. Brain T/B was higher after the tertiary amine compound. Results showed marked cardioselectivity of radioactivity after [14C] MDL74270. Differential centrifugation of heart homogenates showed that radioactivity was equally distributed between the major subcellular fractions studied.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
39.
During the light phase of a light/dark cycle, dendrites of teleost cone horizontal cells display numerous finger-like projections, called spinules, which are formed at dawn and degraded at dusk, and are thought to be involved in chromatic feedback processes. We have studied the oscillations of these spinules during a normal light/dark cycle and during 48 h of constant darkness in two groups of strongly rhythmic, diurnal fish, Aequidens pulcher. In one group the retinal dopaminergic system had been destroyed by the application of 6-OHDA, while in the other (control) group, the dopaminergic system was intact. In control fish, oscillations of spinule numbers were observed under both normal and constant dark conditions, indicating the presence of a robust circadian rhythm. However, spinule dynamics were severely affected by the absence of retinal dopamine. During the normal light phase, the number of spinules in 6-OHDA injected retinae was strongly reduced, and throughout continual darkness, spinule formation was almost completely suppressed. These results indicate that dopamine is essential for both light-evoked and circadian spinule formation; furthermore, we conclude that there is no circadian oscillator within horizontal cells controlling the formation of spinules.  相似文献   
40.
VC is an important clinical entity; however, very little information is available on its resolution. Induction and regression of calcitriol-induced VC was studied in 47 rats. After calcitriol withdrawal, there was a relatively rapid regression of VC mediated by an active cellular process. INTRODUCTION: Vascular calcifications (VCs) represent an important risk factor for cardiovascular death. Although VCs are prevalent in relevant diseases (e.g., chronic kidney disease, osteoporosis, diabetes), the reversibility of extraskeletal calcifications is an unresolved issue. This study was conducted to investigate (1) the in vivo effect of calcitriol on VC and (2) whether calcitriol-induced VC would regress after suppression of calcitriol treatment. MATERIALS AND METHODS: The calcifying effect of calcitriol was studied in four groups of rats (n = 8) that received calcitriol (1 mug/kg, IP) for 2, 4, 6, and 8 days. The reversibility of VC was studied in three additional groups (n = 5) treated with 1 mug/kg of calcitriol for 8 days that were subsequently killed 1, 2, and 9 weeks after the last calcitriol dose. Aortic VC was assessed by histology and by quantification of aortic calcium and phosphorus content. The aortic wall was studied by histology and immunohistochemistry. Statistical analysis was performed by ANOVA and t-tests. RESULTS: Calcitriol administration resulted in a time-dependent induction of VC, with aortic calcium and phosphorus being significantly increased at 6 and 8 days. Treatment with calcitriol for 8 days resulted in massive medial calcification of the aorta with a 10- to 30-fold increase in the aortic Ca and P content. After suppressing calcitriol administration, a progressive decrease in von Kossa staining and aortic Ca (from 32.8 +/- 2.5 to 9.3 +/- 1.8 mg/g of tissue, p < 0.001) and P (from 11.9 +/- 1.2 to 2.7 +/- 1.8 mg/g of tissue, p = 0.001) content was evidenced. Histology of the aortic wall showed monocytes adhered to the aortic endothelium and macrophages involved in the reabsorption of calcium deposits. CONCLUSIONS: Our results show that calcitriol treatment induces time-dependent VC. After calcitriol withdrawal, VC regress rapidly with aortic calcium and phosphorus decreasing by 75% in the course of 9 weeks. An active cellular process seems to be involved in regression of VC.  相似文献   
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