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81.
The oxygen transport system is an important component in the limitation of endurance performance in able-bodied and paraplegic athletes. The aim of the present study was to investigate the total haemoglobin mass (tHb, carbon monoxide rebreathing method) and cardiac volume (HV, echocardiography) in 25 highly endurance trained male spinal cord injured (mainly paraplegic) athletes (SCI-TRAINED) and to compare the results with those of 10 untrained spinal cord injured controls (SCI-UNTRAINED) and in 25 able-bodied elite endurance athletes (TRAINED). tHb and tHb/kg were higher in SCI-TRAINED than in SCI-UNTRAINED (748 ± 110 vs. 629 ± 209 g (464 ± 68 vs. 390 ± 130 mmol) (mean ± SD), P = 0.02 and 10.3 ± 1.3 vs. 7.9 ± 2.0 g/kg (6.4 ± 0.8 vs. 4.9 ± 1.2 mmol/kg), P < 0.0001), while HV and HV/kg showed no significant differences between the two groups (765 ± 93 vs. 793 ± 164 ml and 10.6 ± 1.4 vs. 10.3 ± 2.5 ml/kg). No difference between SCI-TRAINED and TRAINED was found for septal diameter (9.5 ± 1.0 mm vs. 9.7 ± 0.7 mm). However, tHb and tHb/kg in SCI-TRAINED was lower than in TRAINED [896 ± 123 g (556 ± 76 mmol), P = 0.0003 and 12.6 ± 1.3 g/kg (7.8 ± 0.8 mmol), P < 0.0001]. In spinal cord injured athletes, tHb but not HV adapts moderately to chronic endurance exercise, although tHb in spinal cord injured athletes does not reach the level of able-bodied-trained persons.  相似文献   
82.
This paper investigates the association between individually measured socioeconomic status (SES) and all-cause survival in colorectal cancer patients, and explores whether factors related to the patient, the disease, or the surgical treatment mediate the observed social gradient.  相似文献   
83.
OBJECTIVE: As an extension of our previous observation, relating a serotonin transporter gene-linked promoter region (5-HTTLPR) diallelic functional polymorphism (short [S] and long [L] alleles) to the risk of post-stroke major depression (PSD), this study investigated the role of 2 other functional polymorphisms of the serotonin transporter gene (5-HTT) in the same sample of subjects with PSD. METHOD: In a clinical sample of 26 patients with PSD and 25 unrelated nondepressed stroke patients of Caucasian descent, we examined the frequencies of a functional single nucleotide variant (A/G) within the promoter region (rs25531) and located in L (16-repeat) and S (14-repeat) alleles of 5-HTTLPR, and a variable number tandem repeat (VNTR) polymorphism in intron 2. RESULTS: There were significant intergroup differences in the allelic frequencies of 5-HTTLPR/rs25531 (SA, LA, and LG) (P < 0.05) and in the combined frequencies of lower-expressing alleles (SA and LG) and higher-expressing alleles (LA) (P < 0.025) between subjects with PSD and nondepressed stroke. However, the differences in the combined frequencies of lower-expressing (SA/SA, SA/LG, and LG/LG), intermediate-expressing (SA/LA and LA/LG), and higher-expressing (LA/LA) genotypes of 5-HTTLPR were not significant. Further, no significant intergroup differences were found in the allelic and genotypic frequencies of the intron 2 VNTR. CONCLUSIONS: These findings strengthen the support for an association between PSD and lower-expressing alleles of 5-HTTLPR.  相似文献   
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Smoking Is a Risk Factor for Recurrence of Groin Hernia   总被引:15,自引:0,他引:15  
Studies of connective tissue from patients with inguinal hernia have shown that smoking may be associated with hernia formation due to a defective connective tissue metabolism. Whether smoking is a risk factor for recurrence, too, was examined in this study. From December 1990 through December 1995, 649 patients underwent hernia repair as open sutured repair (Cooper ligament or abdominal ring repair) or as open mesh repair. Five hundred forty-four eligible patients were evaluated for recurrence 2 years postoperatively. Association between recurrence and 17 patient-, disease-, and intraoperative variables were analyzed by multiple logistic regression. The results showed that smoking was significantly and independently associated with recurrence compared to nonsmoking [odds ratio (OR = 2.22; 95% confidence interval (95% CI) = 1.19–4.15)]. Open sutured repair compared to open mesh repair was the most significant predictor for recurrence (OR = 7.23; 95% CI = 3.01–17.37). Surprisingly, local anesthesia was associated with a higher risk of recurrence compared to general anesthesia (OR = 2.44; 95% CI = 1.19–5.09). Potential confounders and other risk factors for hernia recurrence such as age, alcohol consumption, previous surgery, and anatomical characteristics of the hernia were adjusted for in the analysis. In conclusion, smoking is an important risk factor for recurrence of groin hernia, presumably due to an abnormal connective tissue metabolism in smokers.  相似文献   
87.
The purpose of the study was to examine the effect of autogenous bone graft particles and expanded polytetrafluoroethylene (ePTFE) membrane in the treatment of peri-implantitis. The treatment outcome was evaluated by clinical and radiographic methods including quantitative digital subtraction radiography. A total of 64 implants with a titanium plasma-sprayed (TPS) surface was inserted in eight cynomolgus monkeys (Macaca fascicularis). After a 3-month healing period with plaque control, experimental peri-implantitis characterized by a bone loss of 4-6 mm was established during 14-22 months. Plaque control was then re-implemented and surgical treatment involving autogenous bone+membrane (B+M), autogenous bone (B), membrane (M), or a conventional flap procedure alone (control) (C) was performed. The animals were killed 6 months after treatment. Healthy peri-implant tissue was established irrespective of the applied surgical procedure. A mean bone gain of 4.7 mm was identified around implants treated with B+M, while, respectively, 4.0, 3.0, and 1.9 mm were recorded within the B, M, and C groups. Quantitative digital subtraction radiography confirmed considerable bone gain within defects treated with autogenous bone with or without membrane coverage. The bone gain, especially for defects treated with B+M, seemed to be almost to the level before development of peri-implantitis. By contrast, 38 and 25% of the defect was on average characterized by bone gain when, respectively, M or C was used alone. The present study of implants with a TPS surface in cynomolgus monkeys thus demonstrates considerable bone regeneration after treatment of experimental peri-implantitis with autogenous bone graft particles with or without ePTFE membrane coverage. Further stereologic and histologic evaluation of the treatment outcome is necessary before final conclusions about the effect of autogenous bone graft and ePTFE membrane can be made.  相似文献   
88.
In this study, a second case of hyperinsulinemic hypoglycemia due to activation of glucokinase is reported. The 14-year-old proband had a history of neonatal hypoglycemia, treated with diazoxide. He was admitted with coma and convulsions due to nonketotic hypoglycemia. His BMI was 34 kg/m(2), and his fasting blood glucose ranged from 2.1 to 2.7 mmol/l, associated with inappropriately high serum levels of insulin, C-peptide, and proinsulin. An oral glucose tolerance test (OGTT) showed exaggerated responses of these peptides followed by profound hypoglycemia. Treatment with diazoxide and chlorothiazide was effective. His mother never had clinical hypoglycemic symptoms, even though her fasting blood glucose ranged from 2.9 to 3.5 mmol/l. Increases in serum insulin, C-peptide, and proinsulin in response to an OGTT suggested a lower threshold for glucose-stimulated insulin release (GSIR). Screening for mutations in candidate genes revealed a heterozygous glucokinase mutation in exon 10, substituting valine for alanine at codon 456 (A456V) in the proband and his mother. The purified recombinant glutathionyl S-transferase fusion protein of the A456V glucokinase revealed a decreased glucose S(0.5) (the concentration of glucose needed to achieve the half-maximal rate of phosphorylation) from 8.04 (wild-type) to 2.53 mmol/l. The mutant's Hill coefficient was decreased, and its maximal specific activity k(cat) was increased. Mathematical modeling predicted a markedly lowered GSIR threshold of 1.5 mmol/l. The theoretical and practical implications are manifold and significant.  相似文献   
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90.
The aims of the study were to study chronic pain in land mine accident survivors, and to study the impact of trauma and trauma care parameters on chronic pain. The level of chronic pain was registered (patient-rated and by clinical examination) in 57 severely injured adult land mine accident survivors in Cambodia and Northern Iraq more than one year after the accident. As all study patients had been managed by a standardized trauma system, we could assess the impact of injury severity and primary trauma care on chronic pain. 64% of the study patients (n=36) had chronic pain syndromes (non-significant difference between the two countries). 68% of the amputees (19 out of 28) had phantom limb pain. Pre-injury trauma exposure, the severity of the actual trauma, and the quality of trauma care had no impact on end point chronic pain. In 85% of cases (n=48), the economic standing of the patients' family had deteriorated after the accident. Patient-rated loss of income correlated with the rate of chronic pain syndromes.  相似文献   
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