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1.
Autopsy and imaging studies show that liver involvement is common in cystic fibrosis. However, complications of chronic liver disease including portal hypertension and variceal bleeding are infrequently encountered, and the degree to which variceal hemorrhage affects prognosis in cystic fibrosis is unclear. This uncertainty has lead to debate as to whether liver transplantation is indicated in these patients. We describe a case series of 18 patients and compare their survival with a control group of cystic fibrosis patients without liver disease. The median age at first bleed was 20.0 years (range 9.7-30.9). The median survival after first bleed was 8.4 years, compared to 13.0 years in the control group (P = 0.15). A total of 14 patients have died, 9 from respiratory disease with no discernable contribution from their liver disease. Liver disease contributed to 4 deaths. Only 1 patient suffered a fatal hemorrhage, which may have been either variceal or bronchial in origin. Long-term survival is a frequent occurrence in patients with cystic fibrosis who suffer variceal hemorrhage, and age at death is comparable to the general cystic fibrosis population. In conclusion, this suggests that liver transplantation is not indicated in these patients without additional features of liver decompensation.  相似文献   
2.
OBJECTIVES: Research on the mental health and service needs of homeless seniors has been scant. This paper reviews the available literature and presents findings of a Toronto survey in an effort to describe the demographics of homeless seniors, their level of impairment, and their mental and physical health needs. METHODS: We searched the Medline, AgeLine, and PsycINFO databases, using the following key words: elderly homeless, elderly hostel users, and urban geriatrics. To better describe the service needs of the elderly homeless, we obtained demographic data from the Community and Neighbourhood Services Department and distributed a survey questionnaire to 11 Toronto hostel directors. The questionnaire elicited data relating to reasons for shelter use, problem behaviours, and mental health needs of those over age 65 years. RESULTS: Although seniors represent a small percentage of the homeless population, their numbers are growing. The available literature suggests a high prevalence of psychiatric disorders and cognitive impairment in this population, with a greater proportion of older women than men having severe mental illness. Further, our survey suggests that the service needs of elderly hostel users in Toronto differ from those of their younger counterparts. CONCLUSION: The homeless elderly are the most vulnerable of this impoverished population. Although more research is needed to define their mental and physical health needs and ways of meeting them, their characteristics appear to be unique. Geriatric psychiatrists could play a significant role in evaluating and treating this population more comprehensively.  相似文献   
3.
. The purpose of this prospective study was to assess the efficacy of the Gertzbein classification and the Load Shearing classification in the conservative treatment of thoracolumbar burst spinal fractures. From 1997 to 1999, 30 consecutive patients with single-level thoracolumbar spinal injury with no neurological impairment were classified according to the Gertzbein classification and the Load Shearing scoring, and were treated conservatively. A custom-made thoracolumbosacral orthosis was worn in all patients for 6 months and several radiologic parameters were evaluated, while the Denis Pain and Work Scale were used to assess the clinical outcome. The average follow-up period was 24 months (range 12-39 months). During this period radiograms showed no improvement of any radiologic parameter. However, the clinical outcome was satisfactory in 28 of 30 patients with neither pseudarthrosis, nor any complications recorded on completion of treatment. This study showed that thoracolumbar burst fractures Gertzbein A3 with a load shearing score 6 or less can be successfully treated conservatively. Patient selection is a fundamental component in clinical success for these classification systems. Résumé. Cette étude a pour objectif de classer les fractures comminutives du segment thoraco-lombaire de la colonne vertébrale qui ont été traitées de manière conservatrice, conformément à la classification de Gertzbein et à la classification de la répartition des contraintes. Depuis 1997 à 1999, trente malades présentant une fracture comminutive dans le segment thoraco-lombaire de la colonne vertébrale, sans dommages neurologiques, ont été traités de manière conservatoire, conformément aux classifications de Gertzbein et à la notation de la répartition des charges. Les patients ont porté une orthèse thoraco-lombaire pendant 6 mois et on a procédé à une évaluation des paramètres radiographiques. L'échelle de la douleur et du travail de Dennis a été utilisée pour évaluer les résultats. La durée moyenne d'observation des malades a été de 24 mois (de 12 à 39 mois). Bien que les paramètres radiologiques, pendant cette période, n'aient manifesté aucune amélioration, le résultat clinique de ces patients a été satisfaisant pour 93.33% d' entre eux. L'on n'a pas constaté de complications ni de pseudarthroses. La classification de Gertzbein associe le type de fracture au degré d'instabilité mécanique et au dommage neurologique. La classification de la répartition des contraintes relie l'écrasement et le déplacement de la fracture à la stabilité mécanique. Les fractures explosives du segment lombaire de la colonne vertébrale de type A3, selon Gertzbein, degré 6 ou inférieur à 6, selon la classification des contraintes, peuvent être traitées avec succès de manière conservatrice. Le choix judicieux des patients est important pour le succès clinique de cette méthode de classification.  相似文献   
4.
OBJECTIVE: To determine if glucocorticoids and proinflammatory cytokines inhibit bone growth through a common mechanism involving impaired IGF-I signalling. DESIGN: IGF-I (100 ng/ml), dexamethasone (dex) (10(-6)M) and IL-1beta (10 ng/ml) with inhibitors of the PI3K (LY294002) and Erk 1/2 (PD98059 and UO126) IGF-I pathways (all 10 microM) were studied using the ATDC5 chondrocyte cell line and murine fetal metatarsal cultures. RESULTS: IGF-I stimulated ATDC5 chondrocyte proliferation (322%; P < 0.001 versus control). Addition of PD or LY individually to IGF-I supplemented ATDC5 cultures partially reduced proliferation by 32% (P < 0.001), and 66% (P < 0.001), respectively. PD and LY in combination blocked all IGF-I stimulated ATDC5 proliferation. LY significantly reversed IGF-I stimulatory effects on metatarsal growth (P < 0.001), whereas PD and UO treatment had no effect. IGF-I induced ATDC5 proliferation was further decreased when Dex (24%; P < 0.01) or IL-1beta (33%; P < 0.001) were added to PD but not LY cultures. Metatarsal growth inhibition by LY was unaltered by Dex or IL-1beta addition. CONCLUSIONS: Both the PI3K and Erk 1/2 pathways contributed independently to IGF-I mediated ATDC5 proliferation. However in metatarsal cultures, the Erk 1/2 pathway was not required for IGF-I stimulated growth. Dex and IL-1beta may primarily inhibit IGF-I induced bone growth through the PI3K pathway.  相似文献   
5.
This paper presents the experimental part of an investigation on tracking and eliminating organ motion artifacts in x-ray CT cardiac applications with emphasis on imaging coronary calcification. The system methodology consists of a software implementation of the spatial overlap correlator (SSOC) concept in x-ray CT scanners to track the net amplitude and phase of organ motion during the CT data acquisition process. A coherent sinogram synthesis (CSS) method is then used to identify the repeated phases of a periodic organ motion from the information provided by the SSOC process and hence synthesize a new sinogram with no motion effects. Since the SSOC scheme is capable of tracking cardiac motion, it identifies also the projection points associated with minimum amplitude cardiac motion effects. These points are used to identify a 180 degrees plus the fan angle sinogram for image reconstruction. This leads to a retrospective gating (RG) scheme that is based on the output of the SSOC process. Performance comparison of the proposed methodology with the retrospective ECG gating using real data sets with phantoms and human patients provides a performance assessment of the merits of the proposed methods. Real results demonstrate that the new methodology eliminates the requirement for ECG gating. Moreover, the CSS and the new RG methods do not require breath holding and they can be implemented in x-ray CT scanners to image coronary calcification and the heart's ventricles.  相似文献   
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BACKGROUND: When interpreting results of studies undertaken by research networks we need to know how representative volunteer practices and their registered patients are of the total population of practices and patients in their locality. AIM: To compare the following in research and non-research general practices in one region: practice and population demography, morbidity and mortality, selected performance indicators, and health outcomes. DESIGN OF STUDY: Cross-sectional survey. SETTING: Sixty-six Trent Focus Collaborative Research Network general practices and 749 other general practices in Trent, United Kingdom. METHOD: Practice characteristics and GP contract data were obtained from the NHS Executive, Quarry House, Leeds. The Trent Regional NHS Hospital Admission Database was searched to identify all relevant admissions to hospital from all practices between 1 April 1993 and 31 March 1997. Ward-linked data on cancer were obtained from the Trent Cancer Registry. RESULTS: Of the 815 general practices in Trent Region in the study period, 66 (8%) were in the Trent Focus network. They were more likely to be involved in training GPs and to have a female partner. They tended to be larger, with fewer single-handed doctors and younger GPs. Network practices prescribed a higher proportion of generics (median % prescribed/practice = 70%, versus 51%, Mann-Whitney U = 1615, P<0.0001). There were no clinically important differences between hospital admission rates between the two groups or waiting times for surgical procedures. There was no difference in the incidence of cancer and standardised mortality ratios related to the electoral wards of the GP surgery. CONCLUSION: Although there were differences in practice structure and some aspects of performance, we found no important differences in the demography of registered patients, nor in morbidity, mortality, or access to or use of secondary care.  相似文献   
9.
Chromosomal deletions, associated with the loss of normal function of tumour suppressor genes, have been identified in a variety of both familial and sporadic human cancers. Although the molecular pathology of ovarian cancer is not understood, several studies have reported deletions in chromosome 17 in ovarian tumours. We have used 13 restriction site polymorphic, microsatellite, and variable number tandem repeat markers to make a detailed analysis of chromosome 17 deletions in 12 benign and 19 malignant ovarian tumours. Two benign and 11 malignant tumours were informative for at least one marker on each arm of the chromosome. Loss of heterozygosity (LOH) was detected in both arms (by all informative markers) in 5 malignant tumours from four women (three with the disease at FIGO stage la). In a further bilateral ovarian tumour a partial LOH affecting 17q22-q25 was present in one ovary only. By contrast to a number of previous studies, none of the 19 malignant and 12 benign tumours showed ERBB2 (17q12ndash;22) amplification. The data presented show that the loss of a whole copy of chromosome 17 is a frequent and relatively early event in the development of some ovarian cancers. This suggests the possible involvement of multiple chromosome 17 loci in the pathogenesis of ovarian cancer. Equally plausible is that the loss of a whole chromosome copy could be the product of chromosomal instabilities induced by loss of the normal allele of tumour suppressors, such as TP53, located on this chromosome. © 1993 Wiley-Liss, Inc.  相似文献   
10.

Aims

We explored the effect of remote ischaemic conditioning (RIC) on endothelial function and on circulating mediators.

Methods and results

In 20 healthy male volunteers (mean age 31?±?10 years), flow-mediated dilation (FMD) was measured before and after 20?min of arm ischaemia, followed by reperfusion. Remote ischaemic conditioning (RIC) was performed by applying 3 cycles of 5?min of ischaemia of the leg at the onset of index arm ischaemia. Each volunteer underwent the IR-induced vascular injury protocol with and without RIC in a crossover study design.In the control group, IR significantly reduced FMD (5.9?±?2.9% before IR vs. 2.2?±?3.7% after IR; p?<?0.001). This effect was significantly attenuated by performing RIC (FMD of 5.5?±?3.1% before IR vs. 4.0?±?3.4% % after IR; p for interaction?=?0.01). Serum levels of SOD and ADMA increased significantly whereas MCP-1 and VEGF levels decreased significantly.Only changes in SOD levels were significantly related to the degree of RIC induced protection (r²?=?0.34; p?=?0.018).

Conclusion

RIC has protective effects against endothelial IR injury. Our biomarker study suggests that anti-oxidative stress mediators, such as SOD, seem to be more involved in the pathogenesis of RIC-induced protection in humans than angiogenesis factors or chemo-attractant cytokines.  相似文献   
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