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1.
D Monnier† C Vidal‡ L Martin§ A Danzon¶ F Pelletier† E Puzenat† MP Algros†† D Blanc† R Laurent† PH Humbert† F Aubin† 《Journal of the European Academy of Dermatology and Venereology》2006,20(10):1237-1242
BACKGROUND: Dermatofibrosarcoma protuberans (DFSP) is a rare malignant tumour of the skin, with an estimated incidence of 0.8 to five cases per 1 million people per year. OBJECTIVE: To study epidemiological, immunohistochemical and clinical features, delay in diagnosis, type of treatment and outcome of DFSP from 1982 to 2002. METHODS: Using data from the population-based cancer registry, 66 patients with pathologically proved DFSP were included (fibrosarcomatous DFSP were excluded). Each patient lived in one of the four departments of Franche-Comté (overall population of 1 million people) at the time of diagnosis. The main data sources came from public and private pathology laboratories and medical records. The rules of the International Agency for Research on Cancer were applied. RESULTS: The estimated incidence of DFSP in Franche-Comté was about three new cases per 1 million people per year. Male patients were affected 1.2 times as often as female patients were. The trunk (45%) followed by the proximal extremities (38%) were the most frequent locations. DFSP occurred mainly in young adults between 20 and 39 years of age. Mean age at diagnosis was 43 years, and the mean delay in diagnosis was 10.08 years. Our 66 patients initially underwent a radical local excision. Among them, 27% experienced one or more local recurrences during 9.6 years of follow-up. There was one regional lymph node recurrence without visceral metastases. These recurrences were significantly related to the initial peripheral resection margins. We observed a local recurrence rate of 47% for margins less than 3 cm, vs. only 7% for margins ranging from 3 to 5 cm [P=0.004; OR=0.229 (95%, CI=0.103-0.510)]. The mean time to a first local recurrence was 2.65 years. Nevertheless, there was no death due to the DFSP course at the end of the follow-up, and the final outcome was favourable. CONCLUSION: Our study emphasizes the importance of wide local excision with margins of at least 3 cm in order to prevent local recurrence. However, the recent development of inhibitors of signal transduction by the PDGFB pathway should soon modify the surgical strategy, which is often too mutilating. 相似文献
2.
Over the past decade, the unfortunate reality is that the income gap has widened between Canadian families. Educational outcomes are one of the key areas influenced by family incomes. Children from low-income families often start school already behind their peers who come from more affluent families, as shown in measures of school readiness. The incidence, depth, duration and timing of poverty all influence a child’s educational attainment, along with community characteristics and social networks. However, both Canadian and international interventions have shown that the effects of poverty can be reduced using sustainable interventions. Paediatricians and family doctors have many opportunities to influence readiness for school and educational success in primary care settings. 相似文献
3.
R Zachariah AD Harries MP Spielmann V Arendt D Nchingula R Mwenda O Courtielle P Kirpach B Mwale FML Salaniponi 《Malawi medical journal : the journal of Medical Association of Malawi》2002,14(2):10-12
In Thyolo district, Malawi, an operational research study is being conducted on the efficacy and feasibility of co-trimoxazole prophylaxis in preventing deaths in HIV-positive patients with tuberculosis (TB). A series of cross-sectional studies were carried out to determine i) whether faecal Escherichia coli (E.coli) resistance to co-trimoxazole in TB patients changed with time and ii) whether the resistance pattern was different in HIV positive TB patients who were taking co-trimoxazole prophylaxis. Co-trimoxazole resistance among E.coli isolates in TB patients at the time of registration was 60% in 1999 and 77% in 2001 (p<0.01). Resistance was 89% among HIV-infected TB patients (receiving co-trimoxazole), while in HIV negative patients (receiving anti-TB therapy alone) it was 62% (p<0.001). The study shows a significant increase of E.coli resistance to co-trimoxazole in TB patients which is particularly prominent in HIV infected patients on co-trimoxazole prophylaxis. Since a high degree of plasmid-mediated transfer of resistance exists between E.coli and the Salmonella species, these findings could herald limitations on the short and long term benefits to be anticipated from the use of co-trimoxazole prophylaxis in preventing non-typhoidal salmonella bacteraemia and enteritis in HIV infected TB patients in Malawi. 相似文献
4.
J M Wilson D P Lund C W Lillehei P P O'Rourke J P Vacanti 《Journal of pediatric surgery》1992,27(3):368-72; discussion 373-5
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
5.
BACKGROUND: Partnerships have been investigated in different professions,but other than identifying problems, little work has been carriedout on general practice. OBJECTIVE: The aim of this present study was to develop methods for studyingpartnerships in general practice. METHOD: A tripartite methodological approach was used, with questionnairesadapted from other instruments in use in other professions,followed by an individual interview with each partner, and non-participantobservation at a partnership meeting. Results for one case-studypartnership are given. RESULTS: There were no major differences between the partners on alldimensions measured; the minor differences indicated by theresults of the questionnaires were corroborated by the partnerinterviews and observations. CONCLUSIONS: We conclude that the use of such techniques could provide supportto partnerships going through significant periods of change. Keywords. General practice, interview, observation, partnerships, questionnaire. 相似文献
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A biodegradable nanofiber scaffold by electrospinning and its potential for bone tissue engineering 总被引:49,自引:0,他引:49
Microporous, non-woven poly( epsilon -caprolactone) (PCL) scaffolds were made by electrostatic fiber spinning. In this process, polymer fibers with diameters down to the nanometer range, or nanofibers, are formed by subjecting a fluid jet to a high electric field. Mesenchymal stem cells (MSCs) derived from the bone marrow of neonatal rats were cultured, expanded and seeded on electrospun PCL scaffolds. The cell-polymer constructs were cultured with osteogenic supplements under dynamic culture conditions for up to 4 weeks. The cell-polymer constructs maintained the size and shape of the original scaffolds. Scanning electron microscopy (SEM), histological and immunohistochemical examinations were performed. Penetration of cells and abundant extracellular matrix were observed in the cell-polymer constructs after 1 week. SEM showed that the surfaces of the cell-polymer constructs were covered with cell multilayers at 4 weeks. In addition, mineralization and type I collagen were observed at 4 weeks. This suggests that electrospun PCL is a potential candidate scaffold for bone tissue engineering. 相似文献
10.
Fabrication of a trileaflet heart valve scaffold from a polyhydroxyalkanoate biopolyester for use in tissue engineering 总被引:12,自引:0,他引:12
Sodian R Sperling JS Martin DP Egozy A Stock U Mayer JE Vacanti JP 《Tissue engineering》2000,6(2):183-188
Previously, we reported the implantation of a single tissue engineered leaflet in the posterior position of the pulmonary valve in a lamb model. The major problems with this leaflet replacement were the scaffold's inherent stiffness, thickness, and nonpliability. We have now created a scaffold for a trileaflet heart valve using a thermoplastic polyester. In this experiment, we show the suitability of this material in the production of a biodegradable, biocompatible scaffold for tissue engineered heart valves. A heart valve scaffold was constructed from a thermoplastic elastomer. The elastomer belongs to a class of biodegradable, biocompatible polyesters known as polyhydroxyalkanoates (PHAs) and is produced by fermentation (Metabolix Inc., Cambridge, MA). It was modified by a salt leaching technique to create a porous, three-dimensional structure, suitable for tissue engineering. The trileaflet heart valve scaffold consisted of a cylindrical stent (1 mm X 15 mm X 20 mm I.D.) containing three valve leaflets. The leaflets were formed from a single piece of PHA (0.3 mm thick), and were attached to the outside of the stent by thermal processing techniques, which required no suturing. After fabrication, the heart valve construct was allowed to crystallize (4 degrees C for 24 h), and salt particles were leached into doubly distilled water over a period of 5 days to yield pore sizes ranging from 80 to 200 microns. Ten heart valve scaffolds were fabricated and seeded with vascular cells from an ovine carotid artery. After 4 days of incubation, the constructs were examined by scanning electron microscopy. The heart valve scaffold was tested in a pulsatile flow bioreactor and it was noted that the leaflets opened and closed. Cells attached to the polymer and formed a confluent layer after incubation. One advantage of this material is the ability to mold a complete trileaflet heart valve scaffold without the need for suturing leaflets to the conduit. Second advantage is the use of only one polymer material (PHA) as opposed to hybridized polymer scaffolds. Furthermore, the mechanical properties of PHA, such as elasticity and mechanical strength, exceed those of the previously utilized material. This experiment shows that PHAs can be used to fabricate a three-dimensional, biodegradable heart valve scaffold. 相似文献