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31.
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IntroductionDislocation following total hip replacement continues to be a problem for which no completely satisfactory solution has been found. Several methods have been proposed to reduce the incidence of hip dislocations with varying degrees of success, including elevated rim liners, constrained liners and large diameter bearings. We present our experience with the double mobility acetabular component in patients at high risk of instability.MethodsThis was a retrospective review of 65 primary total hip arthroplasties in 55 patients (15 men, 40 women), performed between October 2005 and November 2009. The majority (80%) of patients had at least two and 26% had at least three risk factors for instability. The mean age was 76 years (range: 44–92 years). The patients were followed up for a mean duration of 60 months (range: 36–85 months).ResultsFourteen patients died and one was lost to follow-up, leaving fifty hips for final assessment. Until the final follow-up appointment, no patients had dislocation and none required revision surgery. The mean Oxford hip score improved from 45.0 to 26.5 (p<0.0001). The mean Merle d’Aubigné pain score improved from 1.4 to 4.9 (p<0.0001), the walking score from 2.3 to 3.1 (p<0.07) and the absolute hip function score from 5.4 to 10.8 (p<0.0001). There were no clinical or radiographic signs of loosening.ConclusionsThe double mobility acetabular component was successful at preventing dislocation during early to medium-term follow-up. However, as data are still lacking with regard to polyethylene wear rates at the additional bearing surface, it would be prudent to restrict the use of this implant to selected patients at high risk of instability.  相似文献   
33.

Introduction

The median survival of patients with glioblastoma multiforme (astrocytoma grade 4) remains less than 18 months despite radical surgery, radiotherapy and systemic chemotherapy. Surgical implantation of chemotherapy eluting wafers into the resection cavity has been shown to improve length of survival but the current licensed therapy has several drawbacks. This paper investigates in vivo efficacy of a novel drug eluting paste in glioblastoma.

Methods

Poly(lactic-co-glycolic acid)/poly(ethylene glycol) (PLGA/PEG) self-sintering paste was loaded with the chemotherapeutic agent etoposide and delivered surgically into partially resected tumours in a flank murine glioblastoma xenograft model.

Results

Surgical delivery of the paste was successful and practical, with no toxicity or surgical morbidity to the animals. The paste was retained in the tumour cavity, and preliminary results suggest a useful antitumour and antiangiogenic effect, particularly at higher doses. Bioluminescent imaging was not affected significantly by the presence of the paste in the tumour.

Conclusions

Chemotherapy loaded PLGA/PEG paste seems to be a promising technology capable of delivering active drugs into partially resected tumours. The preliminary results of this study suggest efficacy with no toxicity and will lead to larger scale efficacy studies in orthotopic glioblastoma models.  相似文献   
34.

Background

A microscopically irradical (R1) resection is a well-known adverse prognostic factor after gastric cancer surgery. However, the prognostic significance of an R1 resection in gastric cancer patients who are treated with chemoradiotherapy (CRT) after the operation has been poorly studied. Therefore, the aim of this study was to evaluate the effect of an R1 resection on (recurrence-free) survival in gastric cancer patients who were treated with CRT after surgery.

Methods

Gastric cancer patients who had undergone a resection with curative intent followed by adjuvant CRT at our institute between 2001 and 2011 were included. CRT consisted of radiotherapy (45 Gy/25 fractions) combined with concurrent capecitabine (with or without cisplatin) or 5-fluorouracil/leucovorin.

Results

A consecutive series of 110 patients was studied, including 80 (73 %) patients who had undergone an R0 resection and 30 (27 %) patients with an R1 resection. Pathologic T-classification (p = 0.26), N-classification (p = 0.77), and histologic subtype according to Laurén (p = 0.071) were not significantly different between these groups. Three-year recurrence-free survival (45 vs. 35 %, p = 0.34) and overall survival (47 vs. 48 %, p = 0.58) did not significantly differ between patients who had undergone an R0 or R1 resection. In a multivariate analysis, pathologic T-classification and N-classification were independent prognostic factors for survival.

Conclusions

A R1 resection was not an adverse prognostic factor in gastric cancer patients who had undergone CRT after the operation.  相似文献   
35.
We have investigated the localization of thrombospondin (TSP), fibrinogen, fibronectin, and von Willebrand factor in human platelets by transmission electron microscopy of antibody-stained ultrathin frozen sections. In negatively stained thin sections, alpha granules were identified on the basis of their smooth, roughly spherical shape, size, single limiting electron-lucent 100 A membrane, and frequent presence of electron-dense nucleoid. In contrast, mitochondria exhibited characteristic double membranes and cristae. Sections were separately stained with affinity-purified polyclonal antibodies to these proteins as well as with three monoclonal anti-TSP antibodies. Antibody specificity was documented in radioimmunoassays, by immunofluorescent cross-blocking, and by staining of bands of appropriate mobility in Western blots of whole platelets. Bound antibody was visualized using a 5-nm colloidal gold-avidin conjugate. In resting cells, staining of virtually all alpha granules was observed for all four proteins. In contrast, consistent staining was absent from other organelles, including plasma membranes, mitochondria, and vacuolar structures that may represent the open canalicular system.  相似文献   
36.
Tsai  LH; White  L; Raines  E; Ross  R; Smith  RG; Cushley  W; Ozanne  B 《Blood》1994,83(1):51-55
Platelet-derived growth factors (PDGF) are potent regulators of cell proliferation. The three isoforms of PDGF AA, AB, and BB are encoded by two genes: PDGF A and PDGF B. The v-sis oncogene is homologous to the PDGF-B gene. v-sis can transform cells that express the appropriate PDGF receptors. Two different types of receptors, PDGF-alpha and PDGF- beta, also encoded by two genes, have been identified. We show that two cell lines. SMS-SB and NALM-6, both derived from pre-B-cell acute lymphocytic leukemias, express the PDGF-A chain gene, and one of them, SMS-SB, releases PDGF-A chains into the media. The SMS-SB cells also express the PDGF-beta receptor, whereas NALM-6 cells express the PDGF- alpha receptor and bind PDGF. This extends the possible targets for PDGF to the B-cell lineage lymphocytes.  相似文献   
37.
Foon  KA; Nakano  GM; Koller  CA; Longo  DL; Steis  RG 《Blood》1986,68(1):297-300
Two patients with hairy cell leukemia with massive splenomegaly and severe pancytopenia were treated with recombinant alpha-A interferon (IFN-alpha-2a). There was no significant response to a trial of IFN- alpha-2a (11 and 20 weeks) with respect to blood counts or spleen size. Subsequent treatment with 2'-deoxycoformycin (dCF) for 8 consecutive weeks (4 mg/m2/wk) resulted in normalization of spleen size and a normalization of peripheral blood counts and bone marrow in one patient. The second patient demonstrated a reduction in spleen size and improved blood counts following 9 weeks of dCF therapy but eventually became refractory. This demonstrates that dCF is non-cross-resistant with interferon and confirms the efficacy of dCF in nonsplenectomized patients.  相似文献   
38.
Background As the prevalence of chronic disease amongst older workers is high and increasing, it is important to know if the large subgroup of older workers with chronic disease has specific needs when it comes to prolonging participation in paid work. Objectives To investigate differences and similarities in predictors of having paid work in workers aged 55+ with and without chronic disease. Methods Workers aged 55–62 years were selected from the 2002–2003 cohort of the Longitudinal Aging Study Amsterdam (n = 333). Potential predictors were: health, personality, work characteristics, and demographics. Per potential predictor, a logistic regression coefficient for ‘having paid work in 2005–2006’ was calculated for workers with and without chronic disease. A pooled estimate was computed and differences between the pooled estimate and the coefficients were tested. Results Follow-up data were available for 95 %, of whom 67 % still had paid work. Predictors of having paid work were similar for workers with and without chronic diseases, except for physical workload (χ2 = 5.37; DF = 1) and psychosocial resources at work (χ2 = 5.94; DF = 1). Having more psychosocial resources (OR = 3.57; 95 %CI 1.33–10.0) was predictive for having paid work in workers with chronic disease and not in workers without chronic disease. Lower age, more weekly working hours, no functional limitations, fewer depressive symptoms, lower neuroticism scores, and more sense of mastery were significantly associated with having paid work in all workers. Conclusions Differences between predictors of having paid work between workers with and without chronic disease should be taken into account when aiming to prevent exit from the workforce. In particular the vulnerable subgroup of older workers with chronic disease and low psychosocial resources at work is more likely to quit working.  相似文献   
39.
40.
STUDY OBJECTIVE: To determine the effect of dietary supplementation with n-3 polyunsaturated fatty acids (n-3 PUFA) on disease variables in patients with rheumatoid arthritis. DESIGN: Multicenter, randomized, placebo controlled, double blind. SETTING: Three Danish hospital Departments of Rheumatology. PATIENTS: Fifty-one patients with active rheumatoid arthritis. INTERVENTION: Random allocation to 12 weeks of treatment with either six n-3 PUFA capsules (3.6 g) or six capsules with fat composition as the average Danish diet. MAIN RESULTS: Significant improvement of morning stiffness and joint tenderness. No significant effect on the four other assessed clinical parameters. No serious side effects. CONCLUSIONS: Dietary supplementation with n-3 PUFA in patients with rheumatoid arthritis improved two out of six patient reported disease parameters. Further studies are needed to clarify the more precise role of n-3 PUFA in the treatment of rheumatoid arthritis.  相似文献   
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