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781.
Purpose. Serum postoperative matrix metalloproteinase 2 (MMP-2) level is a predictor of outcome in node positive breast cancer and can be used to stratify patients into low and high risk groups. Our aim was to determine how clodronate treatment influences MMP-2 associated clinical outcome.Patients and methods. Women with primary node-positive breast cancer were randomized to control group or to receive oral clodronate for 3 years. Adjuvant chemo- or endocrine therapy was given to all patients. The follow-up time for all patients was 5 years. MMP-2 and MMP-9 levels were quantitatively measured from the serum of 252 patients before and after 1 year clodronate treatment using enzyme-linked immunoassays.Results. In clodronate-treated patients, postoperative MMP-2 levels did not predict 5-year disease-free survival or overall survival (DFS, in low MMP-2 group (<5.32 ng/ml, median) 53% versus in high MMP-2 group (>median) 63%, p=NS; OS, 68% versus 63%, p=NS). When the patients were grouped according to serum MMP-2 levels, survival rates among patients with low MMP-levels were better in control than clodronate treated patients (DFS, 82% versus 53%, p = 0.003; OS, 91% versus 68%, p=0.014). Among patients with high serum MMP-2 levels, no significant difference in DFS or OS was found between control and clodronate groups. In multivariate analysis of low risk patients, independent predictors for DFS were treatment, age, nodal and PgR status, and those for OS treatment together with nodal and ER status. During 12 months follow-up, MMP-2 levels increased significantly more in clodonate receiving patients than in controls (p = 0.002). In comparison, when the patients were grouped according to MMP-9 levels, clodronate also impaired DFS among patients with low MMP-9 levels (82% versus 53%, p = 0.02), but no influence on OS was observed (83% versus 70%, p = 0.09).Conclusions. Clodronate interferes with the prognostic value of serum MMP-2. Clodronate has a negative impact on outcome among patients with low serum MMP-2 and MMP-9 levels, while no such influence is observed among patients with high MMP-2 and MMP-9 levels.  相似文献   
782.
Objectives: To describe a nationwide system for postmarketing follow up of new antirheumatic drugs in Sweden, and to analyse safety and effectiveness in an etanercept treated patient cohort.  相似文献   
783.
We analyze the problem of second-best optimal health insurance in the context of a model in which patients and doctors must decide not only on an aggregate quantity of health services to use in treating various kinds of illness, but also have a choice between different kinds of providers (in particular, outpatient services rendered by primary-care physicians or inpatient services provided by hospital-based specialists). We consider well-informed patients' choices of provider when they have conventional insurance so they only pay part of the cost of their health services, as well as the equilibrium strategies of doctors and patients when there is patient-provider asymmetry; in the latter case we also analyze a managed-care insurance setup under which doctors are paid by capitation. We find that under certain plausible conditions, second-best optimal managed-care plans with supply-side incentives dominate second-best optimal conventional plans that rely on cost control through demand-side cost sharing.  相似文献   
784.
Breast cancer patients with c-erbB-2-positive tumours seem to benefit from anthracycline-based adjuvant chemotherapy. The predictive value of c-erbB-2 for taxane sensitivity is not yet clear. The purpose of this study was to assess whether c-erbB-2 expression is associated with clinical sensitivity to docetaxel (T) or sequential methotrexate and 5-fluorouracil (MF). A total of 283 patients with metastatic breast cancer were initially enrolled in a randomised multicentre trial comparing docetaxel with sequential MF in advanced breast cancer. Paraffin-embedded blocks of the primary tumour were available for 131 patients (46%). c-erbB-2 status was determined by immunohistochemistry using a polyclonal antibody to the c-erbB-2 protein. C-erbB-2 expression was scored in a semi-quantitative fashion using a 0 to 3+ scale. Staining scores 2+ or greater were considered positive. Response evaluation was performed according to World Health Organization (WHO) recommendations. Overall 54 (42%) patients had c-erbB-2-positive tumours. There was no association between treatment outcome and c-erbB-2 overexpression. The overall response rates (RR) (n=128) among c-erbB-2-negative and -positive patients were 35 and 44%, respectively (P=0.359). In the MF arm (n=62), the RR was somewhat higher in the c-erbB-2 overexpressors (33% versus 18%, P=0.18). In the docetaxel arm the RRs were very similar, regardless of the c-erbB-2 expression (53% versus 53%). While several studies have suggested a prognostic and putative predictive significance of c-erbB-2 overexpression in early breast cancer, the significance of c-erbB-2 expression as a predictive factor for response to various cytotoxic treatments in advanced breast cancer is still controversial. In this study, c-erbB-2 expression could not predict response to either MF or T. Thus, tumours over-expressing c-erbB-2 are not uniformly more sensitive to taxanes and c-erbB-2 expression cannot yet be applied clinically as a predictive factor for response in advanced breast cancer.  相似文献   
785.
In many malignant diseases the expression levels of CD44 and its splice variant v6 (CD44v6) have been associated with the prognosis. The purpose of this study was to investigate the clinical significance of CD44 in adult soft tissue sarcomas (STS). 133 STS patients with a limb or superficial trunk tumour treated at the Helsinki University Central Hospital in 1987-1993 with a median follow-up time of 68 months were included in this study. The expression of CD44 and CD44v6 was determined immunohistochemically on paraffin-embedded tumour samples. 95% of the tumours expressed CD44 and CD44v6 was detected in 57%. Strong CD44 expression was associated with low grade (P = 0.04) and small tumour size (P = 0.02). In diploid tumours the CD44 expression was correlated with low S-phase fraction (P = 0.001). High expression of both, CD44 in general as well as that of CD44v6, predicted a higher risk for local recurrence (CD44: P = 0.01 and CD44v6: P = 0.05). Low CD44v6 content of the primary tumour correlated with poor survival (P = 0.02). Determining the expression of CD44 or CD44v6 in a primary STS could be a valuable tool for selecting the group of patients who might benefit from intensified local tumour treatment.  相似文献   
786.
An expression (LN) is presented for the net fluid leakage from the intravascular to the extravascular space in the lung. It is based on a new dog model and is the sum of rate of change in extravascular lung water content (EVLW), thoracic lymph flow, and pleural fluid formation. The rate of change of EVLW (delta EVLW) in ml/kg/h was calculated from repeated measurements of EVLW with a double-indicator dilution technique (dye/cold) and corrected according to the relation between EVLW measured by this technique and gravimetry. LN was studied in lung-healthy mechanically ventilated dogs during a prolonged period of mechanical ventilation with and without the application of a positive end-expiratory pressure of 10 cmH2O (1.0 kPa). During mechanical ventilation, LN was found to be 0.3 ml/kg/h in the basal condition, increasing to 0.5 ml/kg/h (P less than 0.01) after a mean period of 7 h. After the application of a positive end-expiratory pressure (PEEP) of 10 cmH2O (1 kPa) for 0.5-2 h, LN was found to increase significantly, from a mean of 0.3 ml/kg/h to 0.9 ml/kg/h (P less than 0.01). We conclude that LN is a useful quantitative expression in experimental studies on lung fluid balance.  相似文献   
787.
Regional CMRglc was measured in seven healthy volunteers with positron emission tomography using [1-11C]D-glucose. Regional CBF was measured using [11C]fluoromethane. The arteriovenous differences of unlabeled glucose and oxygen together with 11C metabolites were also measured. In addition to the loss of [11C]CO2, a loss of acidic 11C metabolites was also detected. A three-compartment model was applied to the tracer data in the time interval 0-24 min. After correction for the loss of 11C metabolites, the tracer method gave an average CMRglc of 26.4 +/- 1.9 (SD) mumol/100 g/min, close to the value obtained with the Fick principle. After correction for the loss of [11C]CO2 only, the tracer method gave 23.6 +/- 2.1 mumol/100 g/min, compatible with (1/6) CMRO2, obtained with the Fick principle. These results and the time course of the loss of acidic 11C metabolites are consistent with the presence of nonoxidative metabolism of glucose that causes an early loss of mainly [11C]lactate after a bolus injection of the tracer. This implies that [1-11C]D-glucose measures the rate of glucose oxidation rather than the total CMRglc. The experiments using [1-11C]D-glucose were compared to five analogous experiments using [U-11C]D-glucose together with [15O]H2O as a flow tracer. After correction for the loss of [11C]CO2, the two glucose tracers gave similar global values of CMRglc and other parameters associated with glucose utilization, but with labeling in the carbon-1 position, the loss of [11C]CO2 was substantially delayed and the contrast between gray and white matter was improved.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
788.
The effect of graded doses of secretin on exocrine pancreatic growth and cell proliferation was studied in a long-term experiment. After 16.5 and 150 micrograms/kg/24 h of secretin, each administered as two subcutaneous injections daily for 14 days, the pancreatic wet weight decreased, whereas the protein and DNA content of the gland was uninfluenced. When administered as described above for 14 days, 16.5, 50, 150, and 450 micrograms/kg/24 h of secretin did not affect the proliferation rate of ductal, acinar, or centroacinar cells as measured by a labeling index after 7 days of continuous 3H-thymidine administration. In the control groups a higher labeling index was found for ductal cells (19.9%) than for acinar cells (11.0%). During the 7 days of 3H-thymidine administration 80-90% of ductal and acinar cells remained in the G0 phase. There was a significantly higher labeling index in interlobular than in intralobular duct cells.  相似文献   
789.
A 47-year-old woman with a 15-year history of Crohn's disease (CD) developed an adenocarcinoma of the duodenum. The preoperative diagnosis was suspected on radiologic and endoscopic examination and confirmed histologically.  相似文献   
790.
Staphylococcus aureus plays an important role as a bacterial pathogen after traumatic injury. The majority of isolated strains produces alpha-toxin, a 33-kDa protein, with membrane-damaging and lethal effects. The central nervous system (CNS) has been considered as the possible target for the lethal action of this toxin. A transfer of alpha-toxin across an intact blood-brain barrier (BBB) is however unlikely. The aim of the present study was to determine if alpha-toxin is accumulated in CNS regions which lack the BBB function. The distribution of alpha-toxin after intravascular injections, in normal mice and rats as well as in rats subjected to ventral root replantation, was assessed using immunogold technique. The results show that, although alpha-toxin does not cross the BBB, alpha-toxin-like immunoreactivity could be detected in the area postrema and at the optic nerve-retinal junction. Extravasation of alpha-toxin was also shown to occur in the spinal cord even 22 months after ventral root replantation. This finding suggests that axon regeneration after ventral root replantation takes place in a macromolecular environment which is totally different from the normal CNS. The implications of vascular spread of alpha-toxin to regions devoid of BBB function are discussed in relation to the bacterial infections which might complicate severe spinal injuries.  相似文献   
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