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21.
Skin tumors induced in mice by initiation-promotion (2 microg DMBA-2 microg TPA) protocols were found to be under multigenic control. Eighty- one N2 mice from the cross (BALB/cAnPt x SENCARA/Pt)F1 x SENCARA/Pt that were either solidly resistant (no papillomas) or highly susceptible (> or = 7 papillomas/mouse) were subjected to a 'genome scan' using 89 microsatellite markers to check for associations with susceptible and resistant phenotypes. A locus on Chr 5 (Skts4) was found to control the susceptibility of SENCARA/Pt mice and the resistance of BALB/cAnPt mice to papilloma formation. In addition, higher than expected linkage scores were seen for the markers D9Mit271, D11Mit268 and D12Mit56. Further work is required to establish whether genes determining papilloma formation are located in these regions of the genome. In general, no evidence was seen for loss of heterozygosity in microsatellite markers on Chrs 5, 9 and 11 in 17 microdissected papillomas from (BALB/c x SENCARA)F1 hybrid mice.   相似文献   
22.
Bulger EM  Arneson MA  Mock CN  Jurkovich GJ 《The Journal of trauma》2000,48(6):1040-6; discussion 1046-7
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BACKGROUND: Factors influencing the progression of physical impairment to patient-perceived disability are not well known. We sought to better understand this relationship in the setting of injury. METHODS: We followed a cohort of 302 patients with lower extremity fractures over a 1-year period. Physical impairment was assessed by range of motion, strength, and pain. Range of motion and strength were assessed together as a proportion of normal function of the extremity (impairment score). Pain was assessed using a Visual Analogue Scale (VAS) pain score. Disability was assessed using the Sickness Impact Profile (SIP), a widely used measure of patient-perceived limitations of everyday activities attributable to illness. The SIP was administered during hospitalization to assess preinjury baseline. Impairment assessment and readministration of the SIP were performed at 12 months after injury. RESULTS: Impairment in leg function (range of motion and strength) was highly correlated (p < 0.001) with overall SIP score at 12 months, but accounted for only 23% of the variance in overall SIP scores. Likewise, VAS pain score was highly correlated (p < 0.001) with overall SIP score at 12 months, but accounted for only 29% of the variance in overall SIP scores. In a multivariate linear regression analysis, variables that were independently associated with overall SIP score included impairment score, VAS pain score, preinjury SIP, poverty status, education status, social support, having hired a lawyer, and involvement with workers' compensation. These variables accounted for 52% of the variance in overall SIP scores at 12 months. CONCLUSION: The degree of physical impairment accounts for only a small amount of the variance in disability from lower extremity fracture. Identifiable patient characteristics including age, socioeconomic status, preinjury health, and social support together with impairment account for over half of the variance in long-term disability. Further research is needed to increase understanding of other factors that influence the progression of impairment to disability, especially those factors that may be amenable to intervention.  相似文献   
25.
ABSTRACT: BACKGROUND: Heart failure is likely to be particularly prevalent in the nursing home population, but reliable data about the prevalence of heart failure in nursing homes are lacking. Therefore the aims of this study are to investigate (a) the prevalence and management of heart failure in nursing home residents and (b) the relation between heart failure and care dependency as well as heart failure and quality of life in nursing home residents METHODS: Nursing home residents in the southern part of the Netherlands, aged over 65 years and receiving long-term somatic or psychogeriatric care will be included in the study. A panel of two cardiologists and a geriatrician will diagnose heart failure based on data collected from actual clinical examinations (including history, physical examination, ECG, cardiac markers and echocardiography), patient records and questionnaires. Care dependency will be measured using the Care Dependency Scale. To measure the quality of life of the participating residents, the Qualidem will be used for psychogeriatric residents and the SF-12 and VAS for somatic residents. CONCLUSION: The study will provide an insight into the actual prevalence and management of heart failure in nursing home residents as well as their quality of life and care dependency. Trial registration: Dutch trial register NTR2663.  相似文献   
26.
Abstract

To meet the need for emotional support for family members of terminal patients, a weekly group session was established on a cancer unit. The group has allowed family members to share their fears, concerns, and doubts as well as receive support from other individuals experiencing similar traumatic situations. The development and goals of this group are discussed.  相似文献   
27.
BACKGROUND: The disease state of the nephrotic syndrome is characterized by abnormal renal sodium retention that cannot be completely explained by a secondary hyperaldosteronism for the following reasons. Firstly, in rats an enhanced sodium retention is observed before proteinuria with intravascular volume depletion occurs. Secondly, in patients with the nephrotic syndrome, volume expansion with hypertension has been reported despite suppression of the renin-aldosterone system. Therefore, another mechanism for sodium retention must be postulated for this disease state. We hypothesize that this mechanism is a reduced 11beta-hydroxysteroid dehydrogenase 2 (11beta-HSD2) activity, a phenomenon known to cause enhanced access of cortisol or corticosterone to the mineralocorticoid receptor. METHODS: We assessed the 11beta-HSD activity by measuring the urinary ratio of tetrahydrocorticosterone (THB) plus 5alpha-tetrahydrocorticosterone (5alpha-THB) to 11-dehydro-tetrahydrocorticosterone (THA) by gas chromatography-mass spectrometry in rats with puromycin aminonucleoside (PAN)-induced proteinuria and with adriamycin nephrosis. Furthermore, the plasma ratios of corticosterone to 11-dehydrocorticosterone were measured. RESULTS: The urinary ratio of (THB+5alpha-THB)/THA increased in all animals following injection of PAN or adriamycin, indicating a reduced activity of 11beta-HSD. The reduced activity of 11beta-HSD was confirmed by an increased plasma ratio of corticosterone to 11-dehydrocorticosterone. The changes in the glucocorticoid metabolite ratios were already present before significant proteinuria appeared. CONCLUSION: PAN- or adriamycin-treated rats develop proteinuria with a reduced activity of 11beta-HSD, a mechanism contributing to the abnormal sodium retention in nephrotic syndrome.  相似文献   
28.

Background  

The bone mineral density (BMD) of the distal femur decreases by 16-36% within one year after total knee arthroplasty (TKA) because of the femoral component's stress-shielding effect. The aim of this prospective study was to determine the quantitative change from the baseline BMD in the distal femur 1 year after patellofemoral arthroplasty using dual-energy X-ray absorptiometry (DXA).  相似文献   
29.
Summary:  Introduction: Neurocognitive complaints may interfere with long-term antiepileptic drug (AED) treatment and are an important issue in clinical practice. Most data about drug-induced cognitive problems are derived from highly controlled short-term clinical trials. We analyzed such cognitive complaints for the two most commonly used AEDs in a clinical setting using patient perceived problems as primary outcome measure.
Method: All patients of the epilepsy center Kempenhaeghe that received topiramate (TPM) or levetiracetam (LEV) from the introduction to mid 2004 were analyzed using a medical information system, an automated medical file. Patients were analyzed after 6, 12, and 18 months of treatment.
Results: Four hundred and two patients used either TPM (n = 260) or LEV (n = 142); 18 months retention showed a statistically significant difference, revealing 15% more patients that continued LEV compared to TPM: 18 months retention 46% for TPM and 61% for LEV [F (1.400) = 3.313, p = 0.043]. Neurocognitive complaints accounted for a significant number of drug discontinuations and especially the high frequency of neurocognitive complaints in the first period of TPM treatment appeared to be significant different from LEV [F(2,547) = 3.192, p = 0.042]. In the remaining patients, the difference in neurocognitive complaints was not statistically significant.
Conclusion: cognitive complaints are common in TPM treatment and frequently lead to drug withdrawal. The impact of LEV on cognitive function is only mild. This leads to a much higher (15%) drug discontinuation rate for TPM compared to LEV.  相似文献   
30.
OBJECT: Although transpedicular fixation is a biomechanically superior technique, it is not routinely used in the cervical spine. The risk of neurovascular injury in this region is considered high because the diameter of cervical pedicles is very small and their angle of insertion into the vertebral body varies. This study was conducted to analyze the clinical accuracy of stereotactically guided transpedicular screw insertion into the cervical spine. METHODS: Twenty-seven patients underwent posterior stabilization of the cervical spine for degenerative instability resulting from myelopathy, fracture/dislocation, tumor, rheumatoid arthritis, and pyogenic spondylitis. Fixation included 1-6 motion segments (mean 2.2 segments). Transpedicular screws (3.5-mm diameter) were placed using 1 of 2 computer-assisted guidance systems and lateral fluoroscopic control. The intraoperative mean deviation of frameless stereotaxy was < 1.9 mm for all procedures. RESULTS: No neurovascular complications resulted from screw insertion. Postoperative computed tomography (CT) scans revealed satisfactory positioning in 104 (90%) of 116 cervical pedicles and in all 12 thoracic pedicles. A noncritical lateral or inferior cortical breach was seen with 7 screws (6%). Critical malplacement (4%) was always lateral: 5 screws encroached into the vertebral artery foramen by 40-60% of its diameter; Doppler sonographic controls revealed no vascular compromise. Screw malplacement was mostly due to a small pedicle diameter that required a steep trajectory angle, which could not be achieved because of anatomical limitation in the exposure of the surgical field. CONCLUSIONS: Despite the use of frameless stereotaxy, there remains some risk of critical transpedicular screw malpositioning in the subaxial cervical spine. Results may be improved by the use of intraoperative CT scanning and navigated percutaneous screw insertion, which allow optimization of the transpedicular trajectory.  相似文献   
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