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1.
Isolated ultrafiltration, hemodialysis & peritoneal dialysis (Tx) were recently used in the treatment of intractable heart failure (HF). We examined the relation between the response of HF to Tx and the residual kidney functions. Tx was carried out in 17 patients (Pts) with HF who did not respond to aggressive medical treatment. Ten Pts (R) responded to Tx and 7 Pts (N) did not. Serum urea nitrogen (UN), creatinine (Cr), uric acid (UA), sodium (Na), potassium (K), and chloride (Cl) concentrations on admission and before Tx were not different between R and N. Urine UN, Cr, Na, K, and Cl on admission and before Tx were also not significantly different. Fractional sodium excretions (FENa), renal failure indices (RFI), and urine/plasma Cr ratios (U/P Cr) on admission were 2.0 +/- 1.6, 2.7 +/- 2.2, and 30.5 +/- 20.0 in R and 5.9 +/- 4.2, 8.2 +/- 6.0 and 11.5 +/- 3.8 in N. They were significantly different (p less than 0.05). However, these did not differ before and after Tx. These data show that FENa, RFI and U/P Cr might be useful indices in predicting the responsiveness of intractable HF to Tx.  相似文献   
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OBJECTIVE: A joint study was undertaken by the Japanese Society of Renal Cancer to investigate the present status of partial nephrectomy in Japan and to speculate about what may be the indications for partial nephrectomy in patients with renal cell carcinoma. METHODS: Data were tabulated for 469 patients from participating medical institutions and various clinical factors were investigated with regard to disease progression (local recurrence and distant metastasis). RESULTS: Disease progression was observed in 21 patients (4.5%). No significant relation to disease progression was observed for sex, laterality, tumor histology, grade and tumor size. Although patients with solitary tumors displayed excellent prognosis irrespective of tumor diameter, patients with multiple tumors displayed a high likelihood of disease progression. Patients older than 77 years old and patients with imperative indication were found to have a poorer prognosis. CONCLUSION: In patients with solitary tumors, partial nephrectomy can be actively performed, even if the patient displays elective indications and the tumor is >4 cm in diameter. In patients displaying multiple tumors with imperative indications, the decision whether to perform partial nephrectomy should be made by the patients and their physicians after considering the impact on curability and the quality of life.  相似文献   
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A 65-year old female, who had been suffered from rheumatoid arthritis, was admitted to our hospital because of fever, oral ulcers, perianal skin ulcers, petechiae in the both legs, hepatosplenomegaly and cervical lymphadenopathy. Her laboratory data showed severe anemia, leukocytopenia, and thrombocytopenia as well as low PT activity, prolonged APTT, decreased fibrinegen and elevated FDP. In addition to raised values of liver enzymes and triglyceride, marked elevation of several cytokines were found. IgM and IgG class antibodies to cytomegalovirus were demonstrated positive and their titers were 2.60 and 938.0, respectively. The study for the aspiration of bone marrow revealed hemophagocytosis of erythrocytes, leukocytes and thrombocytes. Based upon these findings, she was diagnosed as having hemophagocytic syndrome associated with cytomegalovirus infection. Steroid treatment inducing mini-pulse therapy was introduced to her and bought full recovery from the illness. The association of hemophagocytic syndrome to rheumatoid arthritis was reviewed in the literature and five cases were documented to have good prognosis with steroid treatment.  相似文献   
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By measurements of NO2-/NO3- (NOx) production and Northern blot analysis, we studied the effects of a membrane-permeable cAMP derivative, 8-bromo-cAMP, on the expression of inducible nitric oxide synthase (iNOS) gene and the synthesis of NOx in cultured rat vascular smooth muscle cells (VSMCs). 8-bromo-cAMP stimulated NOx production and increased steady-state levels of iNOS mRNA in rat VSMC in a time- and dose-dependent manner. NG-monomethyl-L-arginine, a NOS inhibitor, completely blocked the 8-bromo-cAMP-induced NOx production, whose effect was partially, but significantly reversed by an excess L-arginine, but not by D-arginine. Compounds that increase intracellular cAMP levels (cholera toxin, forskolin, and 3-isobutyl-1-methylxanthine), all stimulated NOx production. Dexamethasone inhibited the stimulated NOx production, as well as the induction of iNOS mRNA by cAMP. Both actinomycin D and cycloheximide completely blocked the stimulated NOx production by cAMP. Actinomycin D abolished the cAMP-induced iNOS mRNA, whereas cycloheximide remarkably increased iNOS mRNA levels in the presence and absence of 8-bromo-cAMP (superinduction). Actinomycin D, but not dexamethasone, completely abolished the cycloheximide-induced iNOS mRNA. The half-life of cAMP-induced iNOS mRNA was approximately 2 h, whereas no decay in the cycloheximide-induced iNOS mRNA was observed during 12 h. These results demonstrate that iNOS gene is upregulated by cAMP and the superinduction of iNOS mRNA is attributable to increased mRNA stability in rat VSMC.  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   
10.
Department of Urology, School of Medicine, Keio University, Tokyo, Japan
Background Conventional therapy for renal cell carcinoma using interferon (IFN) has shown limited antitumor action. The purpose of our study was to investigate synergistic antitumor effects of IFN and 5-fluorouracil (5-FU), and to elucidate the mechanisms of interaction between the 2 agents in mice.
Methods Antitumor effects and biochemical modulation of murine IFN-α/β and 5-FU were determined against the murine renal cell carcinoma cell line, Renca, in vivo. The activity of thymidylate synthetase and thymidine kinase was measured using cytosolic extracts of the tumors.
Results Combination treatment with IFN-α/β and 5-FU produced a significant enhancement of growth inhibition against Renca tumor. Treatment with 5-FU resulted in a 2.7-fold increase in the total amount of thymidylate synthetase and an 11.6-fold increase in the thymidylate synthetase inhibition rate, while the administration of IFN-α/β did not significantly reduce the 5-FU-induced increase in thymidylate synthetase. The administration of IFN-α/β decreased thymidine kinase activity to 65.5% maximally, compared with that in the control mice or the mice treated with 5-FU.
Conclusions The reduction of thymidine kinase caused by treating the mice with IFN-α/β changes the utilization of exogenous thymidine for DNA synthesis, and may represent the mechanism of the additive antitumor effect of the 2 agents, through the suppression of the salvage pathway for deoxythymidine monophosphate induction.  相似文献   
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