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AIMS: The degradation of the extracellular matrix is intrinsic to the invasion and progression of cancer. Matrix metalloproteinase (MMP)-2 and -9 and their natural inhibitors are involved in this process. The study aims to investigate if plasma MMP-2, -9 and tissue inhibitor of metalloproteinase-1 (TIMP-1) can be useful markers in the diagnosis and prognosis of colorectal cancer (CRC) metastatic liver disease. METHODS: Fifty-seven patients undergoing liver metastasis operation were followed prospectively. ProMMP-2, -9 and TIMP-1 plasma levels were determined by zymography and ELISA, before and after the resection of liver metastases. Data were compared with those of healthy controls (n=51) and primary CRC patients (n=94). The diagnostic and prognostic potential was investigated with ROC-curves and Kaplan-Meier survival analysis. RESULTS: Plasma proMMP-2 levels were lower (P<0.001), and TIMP-1 levels higher (P<0.001) in CRC metastatic liver disease than in healthy controls. If compared to those in primary CRC patients, no differences were found. In ROC-curves, the area under the curve was 0.48 and 0.61 for proMMP-2 and -9, respectively. Plasma proMMP-2, -9 and TIMP-1 levels were unsuitable to predict survival. In both diagnostic and prognostic examinations, CEA proved to be a better marker. In the postoperative follow-up, protracted low levels of proMMP-2 seemed related to disease recurrence. CONCLUSION: The preoperative plasma proMMP-2, -9 and TIMP-1 levels have no potential value as diagnostic or prognostic markers in CRC liver metastatic disease.  相似文献   
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N-l-leucyl-doxorubicin and vinblastine-isoleucinate can be considered as relatively non-toxic prodrugs from doxorubicin and vinblastine, respectively. A comparative analysis was carried out of the anti-tumour activity of the four compounds as well as vintriptol in four human ovarian cancer xenografts different in histology, growth rate and chemosensitivity. Injections were given i.v. weekly twice into mice bearing well-established s.c. tumours. At equitoxic doses, the amount of drug administered for N-l-leucyl-doxorubicin and vinblastine-isoleucinate was respectively 3-fold and 2-fold higher than the doses of the parent compound. N-l-leucyl-doxorubicin induced a growth inhibition > 50% in three out of four human ovarian cancer lines. The anti-tumour effects obtained were significantly better (P < 0.01) than in the case of doxorubicin. Vinblastine-isoleucinate studied in two of these lines could induce a growth inhibition of > 50%. This prodrug appeared slightly less effective than vinblastine. Insignificant growth inhibition (< 50%) was obtained by vintriptol.  相似文献   
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BACKGROUND: The mainstay of treatment for pemphigus is systemic corticosteroids. Different adjuvants have been used to reduce side-effects of long-term corticotherapy. Gold is an anti-inflammatory drug used in autoimmune diseases, whose use has waned with the advent of new immunosuppressive agents. OBJECTIVE: To study the outcome of the use of intramuscular gold treatment of pemphigus vulgaris refractory to previous therapies. METHODS: Thirteen patients with pemphigus vulgaris who had failed to respond to several prior therapies were treated with aurothiomalate, as a steroid-sparing agent. Patients were monitored to assess disease activity and gold toxicity. RESULTS: Seven patients achieved complete remission. Four patients were able to taper prednisone doses, although pemphigus flared when prednisone was discontinued or reduced. Toxicity was observed in the other two patients. CONCLUSIONS: In 53.4% of the patients, the use of chrysotherapy resulted in the complete clearing of the disease, discontinuation of all systemic therapies and induced a long-term clinical remission. Prednisone doses were able to be reduced in the remaining 46.6%. Any side-effects were reversible with drug discontinuation. Gold therapy showed efficacy as a secondary line treatment in refractory pemphigus vulgaris.  相似文献   
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OBJECTIVE: To investigate whether the results of duplex examination 1 year after sapheno-femoral junction (SFJ) ligation might be helpful in predicting long-term results after 5 years. PATIENTS AND METHODS: Follow-up data concerning patients operated on for primary or recurrent varicose veins of the great saphenous vein were studied 1 year and 5 years after surgery, focusing on the thigh and groin region. Clinical examination was undertaken to detect recurrent thigh varicose veins. The site of SFJ ligation was carefully screened for any signs of neovascularisation by duplex ultrasound. Sensitivity, specificity, positive and negative predictive value of the 1-year duplex scan were calculated, based upon the outcome of a further duplex scan 5 years following surgery. RESULTS: A total of 100 limbs were studied: 50 limbs operated on for primary varicose veins and 50 limbs for recurrent varicose veins. The 1-year duplex ultrasound of the SFJ ligation site had a sensitivity of 80%, a specificity of 91%, a positive predictive value of 70% and a negative predictive value of 95% in assessing the 5 year recurrence rate. CONCLUSION: A postoperative duplex scan of the SFJ 1 year after varicose vein surgery to the great saphenous vein predicts which patients are most likely to have a good outcome 5 years after surgery. The 1-year duplex scan is a reliable diagnostic tool for future studies evaluating the effect of new methods of treating sapheno-femoral incompetence.  相似文献   
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BACKGROUND: Equilibration of hemoglobin concentration after transfusion has been estimated to take about 24 hours, but some studies have shown that earlier measurements reflect steady-state values in persons who have not bled recently. This study was aimed at assessing the changes over time in hemoglobin concentration after transfusion in acutely anemic patients because of recent bleeding. STUDY DESIGN AND METHODS: Thirty-two normovolemic patients recovering from an acute bleeding episode who were no longer thought to be bleeding and who received a 2- unit red cell transfusion were studied. At baseline and 15, 30, 60, and 120 minutes and 24 hours after transfusion, hemoglobin concentration and hematocrit values were measured. RESULTS: The administration of 2 units of packed red cells elicited a 24-hour increase of 22.4 +/− 6.8 g per L in hemoglobin concentration. Hemoglobin values were not different at any of the defined posttransfusion times. Hematocrit levels experienced similar changes over time. Agreement between 15-minute and 24-hour values was excellent, as only 6 percent of patients exhibited a clinically significant difference (> 6 g/L) between the hemoglobin measurements. CONCLUSION: Hemoglobin and hematocrit values rapidly equilibrate after transfusion in normovolemic patients who are recovering from an acute bleeding episode. This fact would allow a rapid assessment of the effects of transfusion and of the recurrence of bleeding in patients remaining at risk.  相似文献   
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Summary— In the present study we have compared the steady state biopharmaceutic characteristics of four diltiazem once daily controlled release capsules: Mono-Tildiem LP 300® (300 mg), Adizem® XL (300 mg)1, Cardizem® (300 mg) and Dilacor® (240 mg). Sixteen healthy male volunteers (aged 22.9 ± 3.3 years, range 19–31 years) completed an open label, multiple oral dose, randomized, four-period crossover study without a washout period in between. The volunteers received each diltiazem formulation once daily for four days. Trough diltiazem and metabolites plasma concentrations were determined on days 3 and 4. The 24-h plasma concentration-time profiles were assessed after the dose on day 4 of each period. The following steady state pharmacokinetic parameters for diltiazem were calculated: the minimum plasma concentration (cmin), the maximum plasma concentration (cmax), the time to reach that concentration (tmax), the time interval during which the plasma concentration exceeds 50% of cmax (t50), the area under the plasma concentration-time curve (AUC72–96) and the peak-to-trough fluctuation (PTF). For the metabolites of diltiazem, N-mono-desmethyl-diltiazem (NDM) and desacetyldiltiazem (DAD), AUC72–96 (AUCNDM and AUCDAD) and the ratio metabolite/parent compound were calculated. Steady state was achieved on day 3. Except one, all controlled release formulations have satisfactory controlled release properties allowing once daily administration. However, significant (P < 0.05) differences were found between the pharmacokinetic characteristics which do not allow exchange of the various formulations. Concentrations well below 50 ng·mL-1 in the morning hours were observed for Dilacor® (240 mg) and Adizem® XL (300 mg), which could be a disadvantage of these formulations as it is well-known that ischaemic events occur at a higher rate during that part of the day. The plasma concentration profiles of NDM and DAD, the major circulating metabolites, parallel the plasma concentration profiles for the parent compound. From a clinical point of view, all treatments were well tolerated.  相似文献   
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BACKGROUND: Cyclosporin has been shown to facilitate renal vasoconstriction and to have an antinatriuretic effect. The existence of an interference of cyclosporin with the vasodilating properties of endothelium mediated by nitric oxide production could mediate these effects. On the other hand, the infusion of the nitric oxide precursor L-arginine has been shown to induce renal vasodilatation and to facilitate natriuresis in normal volunteers. We have investigated the renal effects of the administration of an infusion of L-arginine in renal transplant patients chronically treated with cyclosporin. To facilitate the analysis of the data the effects of the administration of a similar dose of cyclosporin on renal function during the infusion of a vehicle were also investigated during the administration of a vehicle of L-arginine. DESIGN: Ten male renal transplant patients, chronically treated with cyclosporin and with a stable renal function were studied during 2 consecutive days after the administration of the usual morning dose of cyclosporin. The first day they received an intravenous infusion of vehicle and the second the infusion of graded doses of L-arginine (50, 100, 150 mg/kg/h) during 3 consecutive h. RESULTS: The first day, after cyclosporin administration a significant fall (P < 0.01) was observed in natriuresis and kaliuresis in the absence of changes in renal plasma flow and glomerular filtration rate. After the administration of L-arginine significant (P < 0.01) increases of renal plasma flow, glomerular filtration rate, and natriuresis were seen. The increase in blood levels of cyclosporin after its administration did not differ between days 1 and 2. CONCLUSION: These results indicate that L-arginine facilitates renal vasodilatation and natriuresis in renal transplant patients. Furthermore, the observed increase in sodium excretion could indicate that L-arginine counteracts the antinatriuretic effect of cyclosporin.   相似文献   
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