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61.
Nitric oxide (NO) is a short-lived diffusable molecule now believed to participate in multiple physiologic functions in the CNS including neurotransmission and the maintenance of vascular tone. Previously, we reported that cell lines obtained by retroviral immortalization of tissue macrophages (M?;) could be induced to synthesize nitrite (NO), a stable end product of the NO synthetic pathway. We have further characterized the induction and activity of this pathway in a panel of seven microglial clones derived from primary embryonic mouse brain cultures. Like M?;, these clones were found to release high levels of NO-2 in response to recombinant interferon-γ (rIFN-γ) as a priming signal together with either bacterial lipopolysaccharide (LPS) or exogenous recombinant tumor necrosis factor-α (rTNF-α). As previously demonstrated for M?;, phagocytosis of zymosan particles during induction of enzyme activity enhanced subsequent NO production, which is of interest in light of the postulated phagocytic role of microglia within the CNS. Biochemical characterization of enzyme activity in intact microglial clones and in isolated cytosolic fractions indicates that the microglial NO synthase present in these murine cell clones represents the M?;-like isotype. These findings suggest that microglial cells could represent a major source of NO within the CNS.  相似文献   
62.
Summary The prevalence of smoking in pregnancy was analyzed in a survey of women delivering between January and March 1989 in a large maternity clinic in Milan, Northern Italy. Out of the 528 women interviewed, 183 (35%) were current smokers before pregnancy and 99 stopped smoking during pregnancy. The probability of stopping smoking decreased with increasing age and was lower in less educated women, but these findings were not statistically significant. Considering persistent smokers only, the mean number of cigarettes per day fell from 13 before to 8 during pregnancy; this reduction was generally consistent in various subgroups of age and education. The reductions, however, are probably overestimated, since they are based on the women's reports only. Thus, there still appears to be ample scope for intervention on smoking in pregnancy, particularly in older and less educated women.
Zusammenfassung Die Rauchprävalenz während der Schwangerschaft wurde in einer Querschnittstudie bei Frauen untersucht, welche zwischen Januar und März 1989 in einer grossen Frauenklinik in Mailand ein Kind zur Welt brachten. Von 528 befragten Frauen hatten 183 (35%) vor der Schwangerschaft geraucht, und 99 Frauen war es gelungen, während der Schwangerschaft mit Rauchen aufzuhören. Die Wahrscheinlichkeit für letzteres nahm mit zunehmendem Alter ab und war kleiner für Frauen mit geringer Ausbildung (statistisch nicht signifikant). Bei den Raucherinnen wurde eine Reduktion der mittleren Anzahl Zigaretten von 13 Stück vor der Schwangerschaft auf 8 während der Schwangerschaft festgestellt. Diese Reduktion fand sich in allen Alters- und Ausbildungsgruppen. Wahrscheinlich wurde die Reduktion aber überbewertet, weil sich ihre Berechnung nur auf die Aussagen der Frauen abstützte. Für Gesundheitsaktionen, die ein Rauchstopp während der Schwangerschaft zum Ziele haben, besteht immer noch ein grosser Bedarf, besonders bei älteren und weniger ausgebildeten Frauen.

Résumé La prévalence du tabagisme durant la grossese a été étudiée lors d'une enquête des parturientes entre janvier et mars 1989 dans une grande maternité de Milan. Parmi les 528 femmes interrogées, 183 (35%) étaient tabagiques avant la grossesse et 99 avaient arrêté de fumer durant la grossesse. La probalité de cesser l'habitude diminue lorsque l'âge augmente, et est basse chez les femmes dont le niveau d'éducation est bas, sans significantion statistique. En considérant uniquement les parturientes tabagiques, le nombre quotidien de cigarettes fumées passe de 13 avant la grossesse à 8 durant la grossesse; cette diminution se retrouve dans tous les groupes d'âge et tous les niveaux d'éducation. Ces diminutions sont probablement surestimées, puisqu'elles sont basées sur les seules déclarations des parturientes. Cette enquête montre qu'il existe encore une large place por la prévention.
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63.
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   
64.
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   
65.
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.
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66.
67.
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   
68.
69.
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   
70.
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