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991.
992.
BACKGROUND: Patient fitness at the time of organ allocation has an impact on graft survival equivalent to the effect of human leukocyte antigen (HLA) matching. The variation between institutions in assessment of fitness is not known, nor is the potential impact on mean graft survival of incorporating patient fitness into local adult cadaveric-kidney transplant-allocation algorithms. METHODS: Data from the Collaborative Transplant Study (CTS, 1985-2000) were reviewed. Quantitative criteria (QC) of patient fitness based on national transplant society guidelines were compared with subjective categorization (SC) of each patient on the current local transplant waiting list (n=109) determined by their supervising nephrologist. RESULTS: Five-year cadaveric graft survival was 70%, 61%, and 53% for good-, moderate-, and poor-risk patients in the CTS data set (n=102, 612), equivalent to half lives of 12.7, 9.8, and 8.7 years, respectively, with similar results from the local program. The distribution of local waiting-list patients into fitness categories A (good), B (moderate), C (poor), and D (unacceptable) was 51%:31%:13%:5% by SC and 25%:40%:27%:8% by QC. At one hospital, 61% (n=51) of patients were classified category A by SC, and falling to 16% by QC (P<.0001). Compared with preferential category A recipient allocation, an unrestricted allocation policy was estimated to sacrifice 1.5 years of overall program-mean graft survival. CONCLUSIONS: Use of QC may reduce the variation in subjective patient assessment seen between institutions. Any proposed changes in organ allocation methods should address the "equity versus efficiency" balance in an open fashion and predict the impact on the overall graft survival for the program by quantifying the "equity penalty."  相似文献   
993.
BACKGROUND: The purpose of our study was to demonstrate the effectiveness of endovascular stent grafts in the treatment of acutely ruptured thoracic aortic aneurysms and type B dissections as an alternative to the conventional surgical approach in an emergency setting. METHODS: From January 2001 to October 2001, we deployed 11 emergent endovascular stent grafts into the thoracic aorta. We treated seven ruptured aortic aneurysms and four acutely perforated type B dissections. Aortic rupture was confirmed preoperatively by spiral computed tomography. In all cases, hemothorax was present. The average interval from onset of symptoms to treatment was 28.5 hours. We used nine Talent and two Excluder stent grafts. RESULTS: Deployment of the stent grafts was successful in nine cases. There were two cases of access failure due to small caliber of iliac arteries, and 1 of these patients died shortly after the procedure was abandoned, At 12 months of follow-up, there were no cases of paraplegia, stent migration, or endoleaks. There was, however, one temporary renal failure, and 2 patients required mechanical ventilation for more than 48 hours. CONCLUSIONS: Our experiences with emergency endovascular stent grafting show that the procedure is technically feasible, with less morbidity and mortality than conventional open surgery, in high-risk patients.  相似文献   
994.
Pentachlorophenol (PCP) was widely used as a wood preservative in Germany until 1989, when it was prohibited by law. Within a cross-sectional study we investigated the internal PCP exposure of painters and bricklayers between one year and four years after the ban. PCP was analysed in post-shift urine samples of 189 painters and 148 bricklayers by gas chromatography and electron capture detection (GC-ECD). The median PCP concentration in the urine of painters was 2.4 microg/g creatinine (range: 0.2-52 microg/g creatinine). For the bricklayers a range of 0.1-25 microg/g creatinine (median: 1.8 microg/g creatinine) was determined. The difference between both groups was statistically significant, pointing to a small additional uptake of PCP by the painters probably from an exposure to contaminated wood surfaces or residual PCP containing preservatives. The biomonitoring results for both groups coincided with background values of the general population at that time.  相似文献   
995.
Introduction: The etiology of depressive symptoms associated with the transition to menopause is still unknown; hormonal changes, serotonergic system or insomnia, could be a trigger to depressive symptomatology. The aim of the present study was to evaluate gonadal hormonal levels, platelet serotonin concentrations and platelet tryptophan concentrations in a group of depressed perimenopausal women and their healthy counterparts.

Methods: A total of 63 perimenopausal women between 45 and 55 years old were evaluated; of these, 44 were depressed patients, and 19 were perimenopausal women without depression. The instruments that were applied included the Center for Epidemiologic Studies Depression Scale (CES-D), the Hamilton Depression Rating Scale (HDRS) and the Green Climacteric Scale (GCS); gonadal hormone levels and platelet tryptophan and serotonin concentrations were measured in all participants. Differences in hormonal levels and tryptophan and serotonin concentrations were evaluated with respect to specific symptoms, such as insomnia, hot flashes, nervousness, depressed mood and loss of interest.

Results: No differences between groups were observed with respect to hormonal levels and tryptophan and serotonin concentrations; mean sleep hours and insomnia were significantly correlated with platelet tryptophan concentrations.

Conclusions: In this sample, all symptoms of depression could not be explained by platelet tryptophan and serotonin concentrations and hormonal levels; differences were observed only when we evaluated insomnia and hot flashes.  相似文献   

996.

Objective

To determine the effect of short (4 h) and long (4 days) abstinence periods on sperm quality based on functional and biochemical parameters in a population of normozoospermic men.

Methods

Two semen samples were collected in succession from potentially fertile, normozoospermic men (n = 100) after an abstinence period of 4 days and 4 h respectively. The mean values of semen volume, pH, viscosity, sperm concentration, percentage of total and progressively motile sperm, sperm kinematics/velocity, normal morphology, acrosome status, DNA fragmentation, intracellular superoxide (O2??) levels and seminal antioxidant status were compared between the two abstinence duration groups.

Results

A significant increase in total and progressive motility and velocity parameter values were observed after short abstinence compared with long abstinence periods. Sperm DNA fragmentation and intracellular O2?? levels were not significantly different between the two abstinence periods. Despite the decrease in semen volume, sperm concentration and total sperm number after short abstinence periods, all mean values of the conventional semen parameters remained above the lower reference limits as reported by the WHO.

Conclusion

The data from this most comprehensive study of its kind challenges the generally accepted guidelines of the prolonged abstinence periods since the results show that 4 h of sexual abstinence yielded significantly better sperm samples from a functional point of view. Although this study was performed on normozoospermic men, future studies with infertile men might yield similar findings that could lead to employing short abstinence as a strategy to improve the outcome of ART and fertility preservation.  相似文献   
997.
Silver-Russell syndrome (SRS) is a genetically and clinically heterogeneous disease which is mainly characterized by pre- and postnatal growth restriction. The typical SRS phenotype furthermore includes a relative macrocephaly, a triangular shaped face, body asymmetry, clinodactyly of the fifth finger and other less constant features. In about ~50% of patients (epi)genetic alterations involving chromosomes 7 and 11 can be detected. The major finding (~44%) is a hypomethylation of the imprinting control region 1 (ICR1) in 11p15.5 affecting the expression of H19 and IGF2. 4-10% of the patients carry a maternal UPD of chromosome 7 (UPD(7)mat). In a few cases chromosomal rearrangements have been reported. The diagnostic workup should therefore include 11p15 testing, UPD(7)mat analysis and molecular karyotyping. The recurrence risk is generally low in SRS but it can strongly increase in case of familial epimutations or chromosomal rearrangements. Interestingly, in ~7% of 11p15 hypomethylation carriers, hypomethylation of additional imprinted loci can be detected. Clinically, patients with hypomethylation at multiple loci do not differ from those with isolated ICR1 hypomethylation whereas the UPD(7)mat patients generally show a milder phenotype. Nevertheless, an unambiguous (epi)genotype-phenotype correlation can not be delineated. Furthermore, the pathophysiological mechanisms resulting in the SRS phenotype still remain unknown despite the recent progress in deciphering molecular defects in the disease.  相似文献   
998.
We report a case of acute near-fatal cerebellar swelling, which was accompanied by multifocal cerebellar necrosis. Acute, near-fatal cerebellar swelling is a rare problem thought to be of parainfectious aetiology. Initiation by multifocal cerebellar necrosis has not been reported so far with this disorder.  相似文献   
999.
OBJECTIVE/HYPOTHESIS: One of the most important functions of the nose is the climatization of inspired air. The aim of the investigation was to determine the influence of radical sinus surgery with complete resection of the turbinates and the lateral nasal wall by means of midfacial degloving as treatment for inverted papilloma on the nasal humidification and heating of inspired air. STUDY DESIGN: Retrospective study. METHODS: Humidity and temperature were measured in the nasopharynx during normal respiration by means of a miniaturized thermocouple device and a humidity sensor for continuous detection. Eight patients after prior unilateral sinus surgery by means of midfacial degloving for a one-sided inverted papilloma were enrolled into the study. The humidity and temperature data of the surgically treated side were compared to the values of the healthy side that was not surgically treated. Active anterior rhinomanometry and acoustic rhinometry were performed. RESULTS: At the end of inspiration, absolute humidity and temperature values in the nasopharynx were statistically significantly lower on the surgically treated side compared with the side that was not surgically treated. CONCLUSIONS: Radical sinus surgery with resection of the turbinates by means of midfacial degloving seems to disturb the climatization of the inspiratory air in the nasal cavity. Reduced absolute humidity and temperature may contribute to crusting, bleeding, and nasal dryness as frequent complaints of patients after aggressive sinus surgery with resection of the turbinates.  相似文献   
1000.
Adult GH deficiency (AGHD) is characterized by an altered body composition, an atherogenic lipid profile, decreased exercise capacity, and diminished quality of life. We performed a randomized, double-blind, placebo-controlled, multicenter study in 166 subjects with AGHD to assess the effects of GH on these outcomes. GH was initiated at 0.0125 mg/kg.d, increased to 0.025 mg/kg.d as tolerated, or decreased to 0.00625 mg/kg.d for 12 months. Primary measures of efficacy included body composition, strength and endurance, and quality of life. Additional parameters included serum IGF-I concentrations, serum lipids, and bone mineral density. After 12 months, 79% of subjects remained on GH 0.0125 mg/kg.d, whereas 21% received 0.00625 mg/kg.d. GH-treated men and women demonstrated significant decreases in total body and trunk fat and increases in lean body mass over baseline. In GH-treated men, mean IGF-I SD scores exceeded age-adjusted normal ranges, whereas similar doses produced a smaller response in women. GH treatment was associated with significant improvements in total cholesterol and low-density lipoprotein (P < 0.05 for all). No significant treatment effects were observed in strength and endurance, quality of life, or bone mineral density. GH treatment was generally well tolerated. Subjects with AGHD should receive individualized GH therapy to maintain IGF-I between the mean value and +2 SD and improve body composition and cardiovascular risk factors.  相似文献   
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