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31.
INTRODUCTION: Acetaminophen (paracetamol) overdose (AOD) has recently emerged as the leading cause of acute liver failure (ALF) in the United States, with an incidence approaching that seen in the United Kingdom. We describe a new way to treat AOD ALF patients fulfilling King's College criteria for "super-urgent" liver transplantation. METHODS: Beginning in June 1998, we have been piloting a clinical program of subtotal hepatectomy and auxiliary orthotopic liver transplantation (ALT) for AOD ALF. Our technique is based on the following principles: (1) subtotal hepatectomy; (2) auxiliary transplantation of a whole liver graft; (3) gradual withdrawal of immunosuppression after recovery. Results were compared with patients who had undergone an orthotopic liver transplantation (OLT) for AOD ALF in the same period. Quality of life comparisons were made using the SF36 questionnaire. RESULTS: Thirteen patients underwent this procedure between June 1998 and March 2005. Median survival is 68 months (range, 0-102 m). Actual survival data show that 9 of 13 patients are alive (69%) compared with 7 of 13 OLT patients (54%). One ALT patient required a retransplantation with an OLT due to hepatic vein thrombosis, and immunosuppression is therefore maintained. The other 8 surviving ALT patients are off immunosuppression. These 8 ALT patients have normal liver function and have a better quality of life compared with the 7 surviving OLT patients. CONCLUSION: Our results with this new technique are encouraging: 69% actual survival, no long-term immunosuppression requirement, and improved quality of life in the 62% successful cases.  相似文献   
32.
Lesions of the articular surfaces of the knee have been managed by various techniques over the last 50 years. Surgical management has involved: excising the damaged area, refashioning the underlying bone to produce a fibrous response, and introducing allograft, autograft and synthetic materials to encourage a repair matrix. The techniques and their pitfalls are reviewed and discussed, and suggestions made as to the direction of future studies for the repair of osteochondral lesions in the painful knee.  相似文献   
33.
Soft-tissue sarcomas (STSs) constitute more than 30 histologic entities. In addition, within each entity, tumors are often heterogeneous in macroscopic features, genetic alterations, microscopic appearance, and clinical course. Therefore, there has been concern about whether a single tumor sample can provide a gene expression profile representative of the entire tumor. We used 27-k cDNA microarray slides to assess the importance of intratumor versus intertumor heterogeneity of the gene expression profiles of 2 morphologically heterogeneous STSs. Multiple pieces of tumor (8 and 10 pieces) were obtained from a myxoid variant of malignant fibrous histiocytoma (MFH) and a leiomyosarcoma (LMS), respectively, and the expression patterns were compared with single tumor samples from 20 MFHs and 16 LMSs. Hierarchical clustering analysis of the expression profiles showed that samples from the same tumor clustered together. The average intratumor distance was considerably shorter than the average intertumor distance in both LMS and MFH. In addition, tumor subclusters that distinguished different macroscopic parts of the tumor could be discerned. We concluded that intratumor variability exists but that accurate gene expression profiling also could be obtained using single samples from a large STS.  相似文献   
34.

Background

Access to pediatric antiretroviral formulations is increasing in resource-limited countries, however adult FDCs are still commonly used by antiretroviral therapy (ART) programs.

Objective

To describe long-term effectiveness of using adult FDC of d4T+3TC+NVP (Triomune) in children for HIV treatment.

Methods

Clinical, immunologic, and virologic outcomes of HIV-infected ART-naïve children aged six months to 12 years, were evaluated up to 96 weeks post-ART initiation.

Results

From March 2004 to June 2006, 104 children were followed with a median age of 5.4 years, median CD4 cell percent and HIV-1 RNA were 11.0% (IQR 6.7–13.9) and 348,846copies/mL (IQR 160,941–681,313) respectively at baseline. Using Kaplan-Meir estimates, 75% of children had undetectable viral loads (<400copies/mL) at 96weeks of ART. Children with a baseline CD4 cell percent >15% were 3 times more likely to achieve viral load <400copies/mL than those with baseline CD4 cell percent <5% after adjusting for baseline age {aHR = 3.03 (1.10–8.32), p=0.03}; no difference was found among those with CD4 cell percent >5–14.9% and <5%.

Conclusion

Treatment with generic adult FDC for HIV-infected Ugandan children led to sustained clinical, immunologic and virologic response during 96 weeks of ART. Early initiation of ART is key to achieving virological success.  相似文献   
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36.
The protective effect of two vaccination regimes using Salenvac, a commercially available iron-restricted Salmonella enterica subsp. Enterica serotype Enteritidis PT4 bacterin vaccine, was verified in laying birds. Immunization was intramuscular at 1 day old and again at 4 weeks of age (V2), or at 1 day and 4 weeks with a third dose at 18 weeks of age (V3). Challenge S . Enteritidis (5 to 7.5) × 10 7 colony forming units) was given intravenously at 8, 17, 23, 30 and 59 weeks of age. For all age groups, both vaccination regimes reduced significantly the number of tissues and faecal samples that were culture positive for the challenge strain. For laying birds, fewer eggs ( P < 0.001) were culture positive for S . Enteritidis after challenge from vaccinated laying birds (56/439 batches of eggs) than unvaccinated birds (99/252 batches). The data give compelling evidence that the vaccine is efficacious and may contribute to the reduction of layer infection and egg contamination.  相似文献   
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Lymphoblasts in bone marrow samples, obtained from 43 children with acute lymphoblastic leukemia at diagnosis, were incubated with 1.0 mumols/L [3H] methotrexate for 24 hours in vitro. Nonexchangeable methotrexate and methotrexate polyglutamates were separated and quantitated. Event-free survival at 5 years was 38% +/- 9% for all 43 patients (27 failures), and 44% +/- 10% for the 35 with non-T, non-B- cell acute lymphoblastic leukemia (20 failures). Of these 35 children, those whose lymphoblasts accumulated more than 100 pmol methotrexate and 500 pmol methotrexate polyglutamates per billion cells experienced better 5-year event-free survival than those whose lymphoblasts did not (65% +/- 12% v 22% +/- 9%, P = .010). This difference characterized "good-risk" patients who were female (P = .014), less than age 7 at diagnosis (P = .005), or had low initial white blood cell counts (less than 20 X 10(9)/L, P = .018). Findings were similar for the 43 children with acute lymphoblastic leukemia and for the "good-risk" children in this total group. Thus, the ability of lymphoblasts to accumulate methotrexate and form methotrexate polyglutamates may be important to the curative properties of current therapy of acute lymphoblastic leukemia in children, particularly for "good-risk" patients. In such patients, inherent rather than acquired drug resistance may be the initial event leading to treatment failure.  相似文献   
40.
The purpose of this study was to determine the relationship between recruitment of the DI and SM muscles measured as EMG signal amplitudes, the pattern of respiratory muscle recruitment measured with inductive plethysmography, and the intensity of the sensation of dyspnea, measured with 100 mm VAS. Eighteen normal subjects between the ages of 33 and 47 breathed under two conditions: normal controlled breathing and breathing against an inspiratory resistance at 60 percent of their maximal inspiratory pressure (MIP). The PM, RR, duty cycle (TI/TTOT, and VT were held constant. During resistance breathing, VAS dyspnea was increased when EMG-DI decreased; EMG-SM increased in association with the sensation of dyspnea. During inspiratory resistance breathing, dyspnea markedly increased and rib cage and accessory muscle recruitment was the predominant pattern of breathing. These data suggest that dyspnea may be associated with the recruitment of the accessory respiratory muscles rather than the recruitment of the diaphragm.  相似文献   
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