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21.
Thrombosis is common after placement of silicone rubber subclavian vein catheters in patients with malignancy receiving conventional doses of chemotherapy. To determine the incidence of this complication in marrow transplant patients and the effect of different catheter designs on thrombosis rates, patients were randomized to receive either open-ended Hickman catheters or valve-ended Groshong catheters for venous access during the transplantation procedure. A total of 35 catheters were placed, of which 23 were double-lumen (11 Groshong and 12 Hickman) and 12 were single-lumen (six Groshong and six Hickman). Arm venograms were performed on all patients at the time of hematopoietic recovery or occurrence of symptoms of subclavian vein thrombosis. There were 10 cases of total subclavian vein thrombosis (three were symptomatic) and 12 cases of asymptomatic non-occlusive mural thrombi. Only 13 normal veins were found. There was no difference in thrombosis rate between the Hickman and Groshong catheters. Double lumen catheters tended to be more likely to cause total venous occlusion (nine of 23) than single lumen catheters (one of 12) (p = 0.06, Fisher's exact test). We conclude that subclavian vein thrombosis is a common occurrence after placement of silicone rubber catheters for venous access during marrow transplantation. Most cases are asymptomatic. Groshong catheters are just as likely to cause this complication as Hickman catheters.  相似文献   
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Psychiatric aspects of Down's syndrome   总被引:3,自引:0,他引:3  
In a survey study of psychiatric morbidity, based on a representative sample from the Danish mental retardation register, 44 adults with Down's syndrome (DS) were compared with 258 other mentally retarded adults. Assessed by the parameters psychiatric disorder, behaviour problems, neurotic traits, and deviant social interaction, the DS group functioned better on all parameters. However, male and female DS patients were very different, the females constituting a superior well-functioning group while the males had major problems in every area. High prevalence rates of dementia and infantile autism were found in the DS group. General function rapidly decreased with age in DS patients.  相似文献   
25.
The purpose of this study was to assess differences in bereavement outcomes between surviving spouses aged 50 and over who remarried within 4-5 years and those who did not. Fifteen bereaved respondents out of 192 in a longitudinal prospective study who later remarried were compared with 15 other matched nonremarried respondents. Analyses of sociodemographic data, standardized measures of depression, life-satisfaction, resolution of grief, and self-perceived ratings of coping, stress, self-esteem, health and social support were performed with correlated t-tests. Statistically significant differences indicated that over time, the remarried subjects displayed more positive outcomes.  相似文献   
26.
It has been suggested that delayed repair with preoperative stabilization might improve survival in high-risk (symptomatic within 6 hours of birth) congenital diaphragmatic hernia (CDH). This study compares the results of immediate operation versus delayed repair using extracorporeal membrane oxygenation (ECMO) when necessary. Since we first used ECMO in 1984, 101 high-risk CDH infants have been treated. Prior to 1987, we used immediate repair and postoperative ECMO if necessary. Between 1987 and 1990 we combined delayed operation (24 to 36 hours) with preoperative ECMO as necessary. No infant in this series was excluded from ECMO therapy unless absolute contraindications existed (prematurity, intracranial hemorrhage, or other major anomalies). Fifty-five patients received immediate operation and 46 had delayed repair. The two groups were comparable populations based on gestational age, birth weight, age at onset of symptoms, Apgar scores, best postductal PO2 (BPDPO2), and frequency of antenatal diagnosis. There was no statistically significant difference in overall survival between the two groups. Differences in survival among subpopulations (BPDPO2 greater than 100 or less than 100, antenatal diagnosis, inborn v outborn) also are not significant. The requirement for ECMO was similar in both groups. Survivors in the delayed repair group were ventilated longer and on ECMO longer, but had fewer late deaths (greater than 21 days) and fewer pulmonary sequelae (O2 dependency at discharge) than infants in the immediate repair group (P less than .05).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
27.
In this prospective, randomized study the clinical response and toxicity of megestrol acetate (MA) and aminoglutethimide (AG) as second-line treatment in patients with metastatic breast cancer was compared. 176 patients were included, and 150 received treatment greater than 8 weeks and are evaluable for treatment response. The two groups did not differ with regard to prognostic factors. Response rate for the AG and MA groups were 34% and 31% respectively, with duration of response of 13.1 and 13.0 months. Stable disease was obtained in 33% and 35% respectively. No difference was observed in survival. Side effects occurred more frequently in the AG group (42%) than in the MA group (18%).  相似文献   
28.
Thorough sports vision evaluations (SVE) utilizing a 30-test battery of established sports vision tests, variations of commonly accepted procedures, and newly designed instruments and/or methods were performed by the Wisconsin Sports Vision Project (WSVP) staff on 232 teenage male and female high school student athletes. Tests are described and results reveal that a state tournament qualifying girls volleyball team (n = 8) demonstrated significantly better visual skills and abilities than 1) the male and female general high school athlete sample (n = 224), 2) the female athlete sample (n = 78), and 3) the other female volleyball players in the sample (n = 46) in some areas of dominant eye vision contrast sensitivity, distance judgement, dynamic visual acuity, tachistoscopic skills, low light and glare-affected vision.  相似文献   
29.
The choroid plexuses (CPs) form a protective interface between the blood and the ventricular cerebrospinal fluid (CSF). To probe into the pathways by which CPs provide brain protection, we sought to evaluate the efficiency of glutathione conjugation in this barrier as a mechanism to prevent the entry of blood-borne electrophilic, potentially toxic compounds into the CSF, and we investigated the fate of the resulting metabolites. Rat CPs, as well as human CPs from both fetal and adult brains, displayed high glutathione-S-transferase activities. Using an in vitro model of the blood-CSF barrier consisting of choroidal epithelial cells cultured in a two-chambered device, we showed that glutathione conjugation can efficiently prevent the entry of 1-chloro-2,4-dinitrobenzene (CDNB) into the CSF, a model for electrophilic compounds. The duration of this enzymatic protection was set by the concentration of CDNB to which the epithelium was exposed, and this barrier effect was impaired only on severe epithelial intracellular glutathione and cysteine depletion. The conjugate was excreted from the choroidal cells in a polarized manner, mostly at the blood-facing membrane, via a high-capacity transport process, which is not a rate-limiting step in this detoxification pathway, and which may involve transporters of the ATP-binding cassette c(Abcc) and/or solute carrier 21 (Slc21) families. Supplying the choroidal epithelium at the blood-facing membrane with a therapeutically relevant concentration of N-acetylcysteine sustained this neuroprotective effect. Thus, glutathione conjugation at the CP epithelium coupled with the basolateral efflux of the resulting metabolites form an efficient blood-CSF enzymatic barrier, which can be enhanced by pharmacologically increasing glutathione synthesis within the epithelial cells.  相似文献   
30.
OBJECTIVE: This study analyzed the influence of the acquisition method in image-free computer-assisted total knee arthroplasty (CAS-TKA), and the reproducibility of implant planning using BoneMorphing, a 3D morphometric model obtained by a 3D-to-3D elastic registration of statistical models to sparse point clouds acquired directly on the bone surface with a pointer. MATERIALS AND METHODS: Five surgeons (one expert, four trainees) each performed a CAS-TKA hybrid protocol based on morphometric models and landmarks on a cadaveric knee 10 times. In addition, several additional landmarks were digitized during each acquisition. The reproducibility of the implant positioning and sizing, as determined by an implant planning algorithm with morphometric models, was compared to direct digitization accuracy. RESULTS: Femoral and tibial implant positioning parameters with the hybrid protocol resulted in intra-surgeon standard deviations (SDs) of less than+/-1.4 degrees for rotation and 1.9 mm for translation for all surgeons in all directions except for tibial axial rotation (the only parameter determined by a digitized landmark and not recomputed in the 3D model). The variability in individual landmark digitization varied from 2 to 5 mm SD for certain landmarks, with ranges of 15-25 mm across all surgeons. The comparison study showed an improvement in femoral rotation reproducibility with the morphometric model when using the posterior condylar axis. Tibial implant reproducibility for each method was comparable, with the morphometric model giving better results in well-digitized areas such as the tibial plateau. CONCLUSION: A CAS-TKA protocol based on a deformed statistical model offers reproducible implant positioning. Some landmarks, such as distal condyles, show sufficient reproducibility in the direction of interest, while others, such as the anterior tibial tubercle, can lead to hazardous implant positioning. This should be taken into consideration when designing a CAS-TKA system with bony landmarks. In areas where a sufficient number of points have been digitized with good coverage, such as on the distal and posterior femoral condyles or the tibial plateau areas, the information derived from the 3D model is more accurate and reproducible than that derived from digitization. Good training and a guiding user interface are essential to guarantee coverage quality.  相似文献   
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