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To ascertain the magnetic resonance (MR) imaging characteristics of pheochromocytomas and paragangliomas and to compare MR with computed tomography (CT) and iodine-131 metaiodobenzylguanidine (I-131 MIBG), 19 patients (18 with pheochromocytomas, one with a paraganglioma) were studied. The 18 patients with pheochromocytomas had had positive findings with I-131 MIBG scintigraphy. Abdominal pheochromocytomas were generally hypointense compared with normal liver on T1-weighted MR images and extremely hyperintense on T2-weighted MR images. MR imaging was preferable to CT in the evaluation of primary pheochromocytomas due to superior tissue characterization, particularly in the patient with hypertension and borderline catecholamine levels. For patients with recurrent or metastatic disease, the data suggest that I-131 MIBG scintigraphy is the examination of choice.  相似文献   
4.
To characterize the immunological effects of intermittent IL-2 therapy, which leads to selective increases in CD4+ T lymphocytes in HIV-infected patients, 11 patients underwent extensive immunological evaluation. While IL-2 induced changes in both CD4+ and CD8+ cell number acutely, only CD4+ cells showed sustained increases following discontinuation of IL-2. Transient increases in expression of the activation markers CD38 and HLA-DR were seen on both CD4+ and CD8+ cells, but CD25 (a chain of the IL-2 receptor) increased exclusively on CD4+ cells. This increase in CD25 expression was sustained for months following discontinuation of IL-2, and was seen in naive as well as memory cells. IL-2 induced cell proliferation, but tachyphylaxis to these proliferative effects developed after 1 week despite continued IL-2 administration. It thus appears that sustained CD25 expression selectively on CD4+ cells is a critical component of the immunological response to IL-2, and that intermittent administration of IL-2 is necessary to overcome the tachyphylaxis to IL-2-induced proliferation.  相似文献   
5.
Evidence from a controlled, comparative trial indicates that oral pimozide is clinically at least as effective as depot injections of fluphenazine decanoate in the continuation therapy of a group of schizophrenic patients discharged from hospital. The administration of pimozide was associated with fewer unwanted effects. The implications of the findings are discussed.  相似文献   
6.
The NIMH Treatment Strategies in Schizophrenia (TSS) collaborative study group investigated the efficacy of antisychotic drug maintenance strategies involving reduced medication exposure in interaction with applied and supportive family management for the long-term treatment of schizophrenia. Therapy was provided at five centers by 25 clinicians who did not participate in the development of the therapies. They were trained by two of the authors, I.R.H.F and C.W.M, in applied family management, a homebased treatment derived from the behavioral family therapy developed by them. Clinicians' characteristics, selection, and training methods, as well as patient rehospitalization rates, are reported for the two family management conditions. The TSS study represents a bridge between the development of a novel therapy and its dissemination in general clinical practice.  相似文献   
7.
Conclusie De verscheidenheid aan conserveermiddelen die in cosmetica worden toegepast, is zeer groot. Het is wenselijk het gebruik van deze verbindingen zo beperkt mogelijk te houden in verband met ongewenste bijwerkingen voor de gebruikers. Een effectieve conservering van produkten, waarin micro-organismen goed kunnen groeien, is echter noodzakelijk. Deskundige microbiologische begeleiding bij de ontwikkeling en fabricage van cosmetische produkten is dan ook essentieel.

Voordracht gehouden tijdens het symposium Conserveermiddelen op 13 november 1980 te Rotterdam.

Dit artikel wordt gelijktijdig geplaatst in De Waren Chemicus.  相似文献   
8.
STUDY OBJECTIVE: To evaluate the toxicity and potential clinical efficacy of combined therapy with zidovudine and interferon-alpha for patients with Kaposi sarcoma and the acquired immunodeficiency syndrome (AIDS). DESIGN: Nonrandomized, open trial study. SETTING: Outpatient clinic of a government referral-based research hospital. PATIENTS: Volunteer sample of 39 patients with human immunodeficiency virus (HIV) infection and Kaposi sarcoma. Interventions: Patients received zidovudine, 250, 100, or 50 mg orally every 4 hours; 6 weeks after interferon-alpha was begun at a dose of 5 million U/d, and the dose was increased every 2 weeks until a maximum tolerated dose was determined. Patients then received the maximum tolerated dose of the combination for a minimum of 12 weeks before formal efficacy evaluations. MEASUREMENTS AND MAIN RESULTS: In the dose-escalation phase, the ability to tolerate interferon-alpha was clearly related to the zidovudine dose. Of the 13 patients receiving 250 mg of zidovudine, only 1 patient was able to tolerate at least 10 million U/d of interferon-alpha. Of the 12 patients receiving 100 mg of zidovudine, 8 tolerated 10 million U/d, 5 tolerated 15 million U/d, and none tolerated higher doses. Of the 12 patients receiving 50 mg of zidovudine, 8 tolerated 10 million U/d, 7 tolerated 15 million U/d, and 6 tolerated 20 million U/d or more. Dose-limiting toxicities included neutropenia (57%), fatigue (16%), thrombocytopenia (14%), and hepatic dysfunction (10%). Of the 22 patients who received a stable dose of both drugs for 12 weeks, 11 patients had a complete or partial tumor response and 8 showed an anti-HIV effect. Peak serum levels of interferon-alpha (32 to 250 U/mL) and zidovudine (0.40 to 3.85 microM) were in the ranges previously shown to be synergistic against HIV. CONCLUSIONS: Combination therapy with zidovudine and interferon-alpha can be administered to patients with HIV infection and Kaposi sarcoma in doses that effect antiviral and antitumor responses; it appears to have a potential role in managing such patients.  相似文献   
9.

Background

Insomnia is common in primary care. Cognitive behavioural therapy for insomnia (CBT-I) is effective but requires more time than is available in the general practice consultation. Sleep restriction is one behavioural component of CBT-I.

Aim

To assess whether simplified sleep restriction (SSR) can be effective in improving sleep in primary insomnia.

Design and setting

Randomised controlled trial of patients in urban general practice settings in Auckland, New Zealand.

Method

Adults with persistent primary insomnia and no mental health or significant comorbidity were eligible. Intervention patients received SSR instructions and sleep hygiene advice. Control patients received sleep hygiene advice alone. Primary outcomes included change in sleep quality at 6 months measured by the Pittsburgh Sleep Quality Index (PSQI), Insomnia Severity Index (ISI), and sleep efficiency (SE%). The proportion of participants reaching a predefined ‘insomnia remission’ treatment response was calculated.

Results

Ninety-seven patients were randomised and 94 (97%) completed the study. At 6-month follow-up, SSR participants had improved PSQI scores (6.2 versus 8.4, P<0.001), ISI scores (8.6 versus 11.1, P = 0.001), actigraphy-assessed SE% (difference 2.2%, P = 0.006), and reduced fatigue (difference −2.3 units, P = 0.04), compared with controls. SSR produced higher rates of treatment response (67% [28 out of 42] versus 41% [20 out of 49]); number needed to treat = 4 (95% CI = 2.0 to 19.0). Controlling for age, sex, and severity of insomnia, the adjusted odds ratio for insomnia remission was 2.7 (95% CI = 1.1 to 6.5). There were no significant differences in other outcomes or adverse effects.

Conclusion

SSR is an effective brief intervention in adults with primary insomnia and no comorbidities, suitable for use in general practice.  相似文献   
10.
Incubation of human platelets, human neutrophils, or highly metastatic mouse lymphoma cells with sulfate-labeled extracellular matrix (ECM) results in heparanase-mediated release of labeled heparan sulfate cleavage fragments (0.5 less than Kav less than 0.85 on Sepharose 6B). This degradation was inhibited by native heparin both when brought about by intact cells or their released heparanase activity. Degradation of heparan sulfate in ECM may facilitate invasion of normal and malignant cells through basement membranes. The present study tested the heparanase inhibitory effect of nonanticoagulant species of heparin that might be of potential use in preventing heparanase mediated extravasation of bloodborne cells. For this purpose, we prepared various species of low-sulfated or low-mol-wt heparins, all of which exhibited less than 7% of the anticoagulant activity of native heparin. N-sulfate groups of heparin are necessary for its heparanase inhibitory activity but can be substituted by an acetyl group provided that the O-sulfate groups are retained. O-sulfate groups could be removed provided that the N positions were resulfated. Total desulfation of heparin abolished its heparanase inhibitory activity. Heparan sulfate was a 25-fold less potent heparanase inhibitor than native heparin. Efficiency of low-mol-wt heparins to inhibit degradation of heparan sulfate in ECM decreased with their main molecular size, and a synthetic pentasaccharide, representing the binding site to antithrombin III, was devoid of inhibitory activity. Similar results were obtained with heparanase activities released from platelets, neutrophils, and lymphoma cells. We propose that heparanase inhibiting nonanticoagulant heparins may interfere with dissemination of bloodborne tumor cells and development of experimental autoimmune diseases.  相似文献   
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