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991.
A man was found to have a repeatedly positive enzyme immunoassay (EIA) that was confirmed by a western blot with six positive bands. He was told that he was seropositive for the human immunodeficiency virus (HIV), but subsequent EIAs were negative and western blots were either negative or indeterminant. All other HIV-related studies were unrevealing, and no explanation for the false-positive result was found. We have not absolutely eliminated the possibility of mislabeled specimens, but we believe this to be unlikely. The possibility, albeit infrequent, of concomitant false-positive EIAs and western blots should be kept in mind when formulating public policy with regard to HIV testing. 相似文献
992.
993.
Antonio Palumbo Silvano Battaglio Patrizia Napoli Paola Omedè Antonella Fusaro Benedetto Bruno Mario Boccadoro Alessandro Pileri 《British journal of haematology》1994,86(4):726-732
Summary. Interferon-α (IFN-α), interferon-γ (IFN-γ) and dexamethasone (DEX) have shown anti-tumour effects in multiple myeloma (MM) cells. Bone marrow plasma cells from 39 MM patients were cultured to clarify the intensity and specific activity of each compound on bromo-deoxyuridine (BrdUrd) uptake and immunoglobulin (Ig) secretion. BrdUrd uptake was inhibited by recombinant human IFN-γ (100 U/ml) and by DEX (10−6 m ). The stimulation index (StI), i.e. labelling index (LI) of treated samples/controls, was 0·49 0·009 (mean standard error of the mean, MSEM), P =0·0003, and 0·52·0·07 (MSEM), P <0·0001, respectively. Ig secretion was reduced by IFN-α (100 U/ml) and DEX. The secretion index (SI), i.e. Ig quantitation of treated samples/controls, was 0·04 (MSEM), P <0·0001, and 0·52·0·04 (MSEM), P <0·0001, respectively. Finally, IFN-γ inhibits BrdUrd uptake only and IFN-α secretion only. In 18 patients the simultaneous addition of IFN-α plus IFN-γ mainly paralleled the effect of IFN-γ on BrdUrd uptake and IFN-α on secretion, but did not result in any additive or synergistic effect, though both BrdUrd uptake and Ig secretion were decreased to about the same extent as with DEX. These data indicate that the combination of IFN-α plus IFN-γ and DEX are the strongest inhibitors of both BrdUrd uptake and secretion. Since IFN-α and IFN-γ appear to have a different mechanism of action, their combined use could be considered as a possible new treatment strategy. 相似文献
994.
Clinical phenomenology and neurobiology of cocaine abstinence: a prospective inpatient study 总被引:2,自引:0,他引:2
S L Satel L H Price J M Palumbo C J McDougle J H Krystal F Gawin D S Charney G R Heninger H D Kleber 《The American journal of psychiatry》1991,148(12):1712-1716
OBJECTIVE: This study was undertaken to document symptoms and changes in dopaminergic function emerging after abrupt cessation of cocaine use. METHOD: After admission, 22 patients with DSM-III-R cocaine dependence were observed drug free for 3 weeks. The patient-rated Ribicoff Abstinence Rating Scale, Symptom Rating Scale, Physical Symptom Scale, Patient Rated Anxiety Scale, Beck Depression Inventory, and visual analogue scales for 16 subjective states were completed daily, and nurses rated 13 patients with the global anxiety and depression items of the Short Clinical Rating Scale. Serial blood samples were obtained three times weekly, and the patients' levels of prolactin, growth hormone (GH), and homovanillic acid (HVA) were measured. Their prolactin and GH values were compared with those of matched normal subjects. RESULTS: A total of 62 subjective symptom variables were evaluated. At baseline, the symptom ratings were mildly elevated. At 3 weeks there were significant decreases from baseline in 28 variables and nearly significant decreases in six additional variables. Nurse-rated anxiety and depression also changed, but in a more variable pattern. There was a small but significant increase from baseline over time in plasma prolactin, but there were no significant changes in GH or HVA. The patients' prolactin and GH values did not differ from those of the normal subjects. CONCLUSIONS: These findings suggest that symptoms after inpatient cessation of uncomplicated cocaine addiction are relatively mild and decrease linearly over the first month. Evidence of dysregulated central dopamine function was limited. The findings do not support routine use of pharmacological agents in the inpatient management of such patients. 相似文献
995.
Methods for nuclear transfer and fusion of individual viable nuclei into cells is described. Experimental binucleates have been formed by fusing nuclei from normal fibroblasts, SV40 virus-transformed fibroblasts, and HeLa carcinoma cells into individual diploid fibroblasts which have undergone their total life span (population doublings) and have been maintained in culture for a period of 10–12 weeks (late phase III) prior to the nuclear transfer. Many of the cells receiving additional nuclei replicate and form clones of cells with a limited life span, and the morphology of the cells remains fibroblast-like. 相似文献
996.
Lineage infidelity of a human myelogenous leukemia cell line 总被引:8,自引:0,他引:8
We have analyzed the organization and expression of the immunoglobulin heavy and light chain gene in the human myeloblastic leukemic sublines, ML1, ML2, and ML3, and in the human myeloid leukemic cell lines, HL-60, U937, THP1, and K562. ML1, ML2, and ML3 cells, despite a predominant granulocytic phenotype, express a rearrangement of the immunoglobulin heavy chain gene that typically occurs during the early stages of the B cell differentiation pathway. No rearrangement was found in any of the other cell lines tested. These findings strongly support the notion that, at least in some cases, acute myeloid leukemia (AML) cells represent highly atypical cells with profoundly altered gene expression, rather than cells arrested at a well-defined stage of the myeloid lineage. 相似文献
997.
M Bellisi F P Palumbo G Marchese G Mastrandrea A Sferlazzo D Cacioppo G Anselmo 《Minerva chirurgica》1989,44(5):923-926
Aetiopathogenetic mechanisms and clinical aspects of carotid artery aneurysms are examined and personal experience of arterial reconstruction in one case reported. 相似文献
998.
Preliminary results on ethylene/propene copolymerization in the presence of Cp2Ti(CH3)2/Al(CH3)3/H2O
Vincenzo Busico Lorenzo Mevo Giuseppe Palumbo Adolfo Zambelli Teodorico Tancredi 《Macromolecular chemistry and physics.》1983,184(11):2193-2198
Ethylene/propene copolymerizations were carried out in the presence of the catalyst system Cp2Ti(CH3)2/Al(CH3)3/H2O (Cp = cyclopentadienyl group), and the reactivity ratios r1, r2 were determined through the Fineman and Ross equation and via 13C NMR. A nearly alternating copolymer structure was pointed out. The yields as well as the molecular weights of the copolymers strongly decrease with increasing propene mole fraction in the copolymers. 相似文献
999.
Toma S Raffo P Isnardi L Riccardi L Defrancisci E Maselli G Dastoli G Palumbo R 《International journal of oncology》1997,10(3):597-607
We evaluated in vitro the potentiating and/or synergistic antitumor effects among retinoids (all-trans-retinoic acid, tRA, and 13-cis-retinoic acid, 13cRA), alpha-interferon 2a (alpha-IFN 2a) and tamoxifen (TAM) on both estrogen receptor positive (ER(+)) and negative (ER(-)) human breast cancer cell lines. In our experimental model, the three studied agents showed antiproliferative activity in ER(+) cell lines MCF-7 and ZR-75.1, while alpha-IFN 2a was the most effective drug in the ER(-) cell line MDA-MB-231. Retinoids and TAM exerted a strong apoptotic effect in MCF-7 cells, while such an effect was obtained in MDA-MB-231 cells by alpha-IFN 2a. The tested combinations displayed different effects in the different evaluated cell lines: i) in MCF-7 cells tRA + TAM showed additive activity, both tRA + alpha-IFN 2a and TAM + alpha-IFN 2a association displayed a synergistic effect, and a further potentiation of the antiproliferative action was detected with the triple combination; ii) in ZR-75.1 cell line an additive activity was showed by tRA + TAM and TAM + alpha-IFN 2a, while tRA + alpha-IFN 2a produced synergistic action; iii) in MDA-MB-231 cell line only alpha-IFN 2a displayed a strong antiproliferative effect, and no significant potentiation was exerted by any drug association. The feasibility and activity of such combinations have been tested in two pilot clinical trials on patients with metastatic breast cancer: both the tested associations were tolerable, with good treatment compliance and low toxicity. The different antiproliferative and apoptotic effects observed in vitro on apparently similar breast cancer cell lines prompted us to a further investigation of the mutual biological modulations of these drug combinations, in view of a better selection of patients who might potentially benefit from these treatments. 相似文献
1000.
Twelve patients suffering from recurrent or metastatic, previously treated, STS were given paclitaxel as a 3-hour infusion, with prophylactic medication, in 3-week cycles, at two different dosages: 135 mg/m(2) or 175 mg/m(2) in patients pretreated with less than or equal to 2 or greater than or equal to 3 chemotherapy regimens, respectively. A total of 39 courses was given (median 3, range 2-5). Overall, treatment was relatively well tolerated, major toxicity consisting of grade 2-3 neutropenia (33%); The adopted schedule was feasible in day-hospital setting, with satisfactory patient compliance. Only a partial response was obtained (8%), lasting 4 months; six patients had stable disease and five progressed while on treatment. Our results suggest a lack of activity of paclitaxel in this tumor type. However, the very advanced stage of disease and the strong pretreatment in the evaluated series probably partially account for some of the resistance and such a poor response rate. Further studies might be appropriate with paclitaxel, alone or in combination with other agents, on selected patients in less advanced stage of disease. 相似文献