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61.
Two children with extensive ileal resection are reported. They developed gross haematuria of non-glomerular origin, without stones or nephrocalcinosis. Previous reports indicate that acquired hyperoxaluria is common in children with a variety of intestinal disorders. Our patients had hyperoxaluria. We think that hyperoxaluria may be the cause of haematuria through a pathogenetic mechanism similar to the one ascribed to haematuria secondary to hypercalciuria and hyperuricosuria.  相似文献   
62.
Kinetic parameters of 99mTc and 131I thyroid trapping were compared in 13 patients (30 dynamic studies). The data were analyzed with a six-compartment model including three compartments for extrathyroid spaces. There was a good correlation between the estimates of the total iodide and pertechnetate pools (V4+V5). As expected, the 14 loss rate constant for technetium was always higher than that for iodide.In five euthyroid patients, the unidirectional clearances (R41) with TcO4 and I were generally of the same magnitude. The effect of TSH stimulation appears to be identical for both isotopes: an increase of R41 and the total iodide and pertechnetate pool (V4+V5), a decrease of the isotope loss rate constant (14).In two untreated thyrotoxic patients, the unidirectional clearance of 99mTc was 2.5 times higher than that estimated with 131I. Under administration of antithyroid drug, unidirectional TcO4 clearance was lower than that of iodide in the six patients studied.A similar and greater discrepancy between early 131I and 99mTc kinetics was observed in a patient with congenital goiter. The technetium thyroid trap was only slightly elevated, whereas unidirectional iodide clearance and (V4+V5) were clearly increased.This series of patients suggests that whereas there is a good correlation between early 131I and 99mTc kinetics in euthyroid subjects, a discrepancy exists in patients with spontaneous or acquired dyshormonogenesis. This is confirmed by the segmentary study of a patient with a nodule appearing hot on the 99mTc scintigram and cold on the 131I scan.Research supported by INSERM (CRL 7750943 B)  相似文献   
63.
Lymphocytic infiltration in and around the tumor together with sinus histiocytosis and follicular hyperplasia in regional nodes has been studied in a group of 310 patients with breast cancer treated by standard radical mastectomy. The semiquantitative grading of these particular changes made possible the division of patients into 3 classes of putative host resistance, namely, no or poor reaction, good reaction, and strong reaction. The grading was shown to have a close correlation with prognosis both 5 and 10 years after surgery. More interestingly, the incidence of metastases in the 3 classes was significantly different, i.e. much higher in the non-responder group, thus supporting the hypothesis that prognosis in breast cancer is closely related to a histological picture of cell-mediated immunity against the tumor, and that this resistance probably acts as a local barrier to the diffusion of the tumor.
Résume Chez 310 malades atteintes de cancer du sein et traitées par mastectomie radicale, nous avons étudié l'infiltration lymphocytaire intra- et péritumorale et, dans les ganglions régionaux, l'histiocytose sinusale et l'hyperplasie folliculaire. Par une gradation semiquantitative, les malades ont été divisées en trois groupes de résistance potentielle: pas ou peu de réaction, réaction d'intensité moyenne, forte réaction. Cette gradation est en bonne corrélation avec le pronostic à 5 et 10 ans. De plus, la fréquence des métastases diffère dans les trois groupes; elle est beaucoup plus élevée dans le groupe à réaction nulle ou faible. Ces données confirment l'hypothèse qui admet que le pronostic du cancer du sein est en relation avec les aspects histologiques d'immunité cellulaire antitumorale et que celle-ci agit vraisemblablement comme un barrage local s'opposant à la diffusion de la tumeur.
  相似文献   
64.
65.
PURPOSE: Diflomotecan (BN80915) is an E-ring modified camptothecin analogue that possesses greater lactone stability in plasma compared with other topoisomerase I inhibitors, a potential advantage for antitumor activity. As with other camptothecins, oral administration has pharmacological and clinical advantages. This Phase I study was performed to assess the feasibility of the administration of oral diflomotecan, to determine the maximum-tolerated, dose its bioavailability, and to explore the pharmacokinetics. EXPERIMENTAL DESIGN: An initial i.v. bolus was administered to assess the bioavailability of diflomotecan. Fourteen days later, diflomotecan was administered p.o. once daily for 5 days to adult patients with solid malignant tumors and repeated every 3 weeks. BN80915 and its open lactone form BN80942 were measured. RESULTS: Twenty-two patients entered the study and received a total of 57 cycles of oral diflomotecan at flat dose levels of 0.10, 0.20, 0.27, and 0.35 mg. The main toxicity was hematological, but some patients experienced alopecia, mild gastrointestinal toxicity, and fatigue. At the 0.35-mg dose level, 2 of 4 patients experienced dose-limiting toxicity comprising grade 3 thrombocytopenia with epistaxis and febrile neutropenia in 1 patient and uncomplicated grade 4 neutropenia lasting for >7 days in another. Toxicity was acceptable at the 0.27-mg dose level at which dose-limiting toxicities were observed in 3 of 12 patients (grade 4 neutropenia > 7 days, complicated by fever in 1 patient but without other signs of infection). After two cycles of diflomotecan, 6 patients had disease stabilization, which was maintained in 2 patients for 9 months and >1 year, respectively. Diflomotecan pharmacokinetics were linear over the dose range studied. Systemic exposure correlated with the fall in WBC counts. The mean oral bioavailability (+/-SD) was 72.24 +/- 59.2% across all dose levels. Urinary excretion of BN80915 was very low. CONCLUSIONS: The recommended oral diflomotecan dose for Phase II studies is 0.27 mg/day x 5 every 3 weeks. This regimen is convenient and generally well tolerated with a favorable pharmacokinetic profile and high but variable bioavailability.  相似文献   
66.
67.
The serum levels of interleukin-(IL-)1α, IL-1β, IL-2, IL-6, TNFα, and sIL-2R and the proliferative response of peripheral blood mononuclear cells (PBMC) to phytohemagglutinin (PHA), anti-CD3 monoclonal antibody (mAb), recombinant IL-2 (rIL-2), and the combination of PHA or anti-CD3 mAb with rIL-2 were studied and correlated with serum levels of C-reactive protein (CRP) in women with advanced epithelial ovarian cancer. The expression of CD25 and CD122 subunities of membrane-bound IL-2R on PHA- or anti-CD3 mAb-stimulated PBMC was also studied. In comparisons with the controls, PBMC response to PHA, anti-CD3 mAb, and rIL-2 was significantly lower in the cancer patients. The addition of exogenous rIL-2 to the PBMC cultures increased response in both controls and patients but did not modify the significance of the differences. After stimulation with PHA or anti-CD3 mAb, the percentage of PBMC CD25+or CD122+was significantly lower in patients. The serum levels of IL-1α, IL-1β, IL-6, TNFα, sIL-2R, and CRP were significantly increased in patients compared to the controls. Instead, no differences were observed for serum levels of IL-2. A strong association was found between high serum levels of the above-mentioned cytokines, sIL-2R, and CRP. The results of our study on advanced stage (IIIb–IV) ovarian cancer patients are consistent with the previously reported hypothesis that high IL-6 and/or CRP serum levels may represent an important and independent prognostic factor of the likely outcome in cancer patients.  相似文献   
68.
69.
PURPOSE: Nemorubicin (3'-deamino-3'-[2'(S)-methoxy-4'-morpholinyl]doxorubicin; MMDX) is an investigational drug currently in phase II/III clinical testing in hepatocellular carcinoma. A bioactivation product of MMDX, 3'-deamino-3',4'-anhydro-[2'(S)-methoxy-3'(R)-oxy-4'-morpholinyl]doxorubicin (PNU-159682), has been recently identified in an incubate of the drug with NADPH-supplemented rat liver microsomes. The aims of this study were to obtain information about MMDX biotransformation to PNU-159682 in humans, and to explore the antitumor activity of PNU-159682. EXPERIMENTAL DESIGN: Human liver microsomes (HLM) and microsomes from genetically engineered cell lines expressing individual human cytochrome P450s (CYP) were used to study MMDX biotransformation. We also examined the cytotoxicity and antitumor activity of PNU-159682 using a panel of in vitro-cultured human tumor cell lines and tumor-bearing mice, respectively. RESULTS: HLMs converted MMDX to a major metabolite, whose retention time in liquid chromatography and ion fragmentation in tandem mass spectrometry were identical to those of synthetic PNU-159682. In a bank of HLMs from 10 donors, rates of PNU-159682 formation correlated significantly with three distinct CYP3A-mediated activities. Troleandomycin and ketoconazole, both inhibitors of CYP3A, markedly reduced PNU-159682 formation by HLMs; the reaction was also concentration-dependently inhibited by a monoclonal antibody to CYP3A4/5. Of the 10 cDNA-expressed CYPs examined, only CYP3A4 formed PNU-159682. In addition, PNU-159682 was remarkably more cytotoxic than MMDX and doxorubicin in vitro, and was effective in the two in vivo tumor models tested, i.e., disseminated murine L1210 leukemia and MX-1 human mammary carcinoma xenografts. CONCLUSIONS: CYP3A4, the major CYP in human liver, converts MMDX to a more cytotoxic metabolite, PNU-159682, which retains antitumor activity in vivo.  相似文献   
70.
BACKGROUND AND PURPOSE: The objectives of the current study were to compare genito-urinary (GU) and gastro-intestinal (GI) toxicities as well as biochemical control (bRFS) in prostate cancer, utilizing conventional (2.0 Gy daily) (STD) or hyperfractionated (HFX) conformal irradiation (CRT). HFX (1.2 Gy BID) was chosen as a radiobiological method to try to reduce long term sequelae without compromising local control. PATIENTS AND METHODS: Three-hundred-and-seventy consecutive patients (pts) entered this prospective, non-randomized trial in the period January 1993-January 2003; 209 were treated with STD and 161 with HFX CRT. All were evaluable for acute toxicity analysis, 179 (STD) and 151 pts (HFX) being evaluable for late sequelae and bRFS analyses. Pt characteristics were not statistically different in the two groups. CRT consisted of a 4-field technique for prostate and/or pelvic nodes and a 5-field boost with rectal shielding. Median doses were 74 and 79.2 Gy for STD and HFX patients respectively, the latter dose being isoeffective for tumour control assuming alpha/beta=10 (EQD(2)=73.9 Gy). Median follow-up was 29.4 months (25.2 mos for STD; 37.7 mos for HFX; P<0.01). The two regimens were compared in terms of acute and late GU and GI toxicities and 5-year bRFS by univariate and multivariate analyses. RESULTS: Acute grade> or =2 GU toxicity was higher in the STD group (48.6% versus 37.3% in HFX, P=0.03), while no significant difference was found for acute GI toxicity. Late grade> or =2 GU and GI toxicities were lower in the HFX group (5-year actuarial rate: GU: 10.1% versus 20.3%, P=0.05; GI: 6.0% versus 10.6%, P=0.18). Five-year bRFS were 70% (+/-13.8%, 95% CI) and 82.6% (+/-7.2%) for STD and HFX, respectively (P=0.44); a trend favouring HFX was found in the subgroup of pts who did not receive hormonal therapy (5-year bRFS: 85.9%+/-12.4% versus 63.9%+/-23.8%, P=0.15). Multivariate analysis revealed only risk groups and age statistically related to bRFS but not fractionation regimen. Using the Nahum-Chapman TLCP model and prostate parameter set, which includes hypoxia, the TLCPs are approximately equal for the two regimens, whereas assuming alpha/beta=1.5 and no hypoxia we obtain 73% for the STD group but only 36% for the HFX group. CONCLUSIONS: As expected from radiobiological considerations, HFX reduces GI and GU late toxicities. Concerning early bRFS, our clinical findings suggest that HFX is no less effective than STD when delivering an isoeffective (alpha/beta=10) dose. Despite the relatively short follow-up, this result appears to be inconsistent with a low alpha/beta ratio for prostate cancer.  相似文献   
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