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41.
Extradural sacral (caudal) block was performed in 17 cases (14 patients) of chronic low back pain. In each case 22 ml of a bupivacaine/methylprednisolone solution incorporating a radioopaque dye was injected over a 2-min period. Patients were randomly assigned to receive the injection in the horizontal position or with 15 degrees head-up or head-down tilt applied to the operating table. Results indicate that analgesia is usually more localised than spread of solution determined by x-ray evidence and that higher levels of analgesia are achieved in patients in the head-up position. Possible causes are the differing distribution characteristics of the constituents of the solution and the gravitational effects of posture on cerebrospinal fluid mechanics. Technical problems associated with obesity, congenital abnormalities, vascular uptake of solution, and delayed spread of the injectant due to adhesions are discussed. 相似文献
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D De AJ Kanwar S Handa 《Journal of the European Academy of Dermatology and Venereology》2006,20(7):853-859
BACKGROUND: Diagnosis of atopic dermatitis (AD) depends on clinical features because no definitive diagnostic test exists. Criteria proposed by Hanifin and Rajka (Acta Derm Venereol (Stockh) 1980; Suppl 92: 44-47) were acceptable for hospital-based studies but were found not to be suitable for field studies. A UK working party formulated clinical diagnostic criteria that could be used in both hospital and epidemiological settings. Validation studies of the criteria showed widely variable results, probably due to different clinical settings and ethnicity. AIM AND OBJECTIVE: This study was undertaken to validate Hanifin and Rajka's criteria and to assess the comparative efficacy of their criteria and the UK working party's diagnostic criteria in the diagnosis of AD in a hospital setting in North India. SUBJECTS AND METHODS: This study serially included 101 patients with AD and 48 controls of paediatric age group. The study period was from July 2003 to December 2004. RESULTS: Hanifin and Rajka's criteria (sensitivity 96%, specificity 93.75%, positive predictive value 97% (PPV) and negative predictive value (NPV) 91.84%) had a statistical advantage over the UK working party's diagnostic criteria (sensitivity 86%, specificity 95.83%, PPV 97.75% and NPV 76.67%), with a P-value < 0.005. 相似文献
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Modulation of the expression of P-glycoprotein, a plasma membrane protein associated with multidrug resistance, was examined in drug-sensitive and drug-resistant tumor cells treated with leukoregulin, a M(r) 50,000 cytokine from human lymphocytes that rapidly permeabilizes the plasma membrane of many tumor cells facilitating the uptake of doxorubicin and other tumor-inhibitory antibiotics. P-glycoprotein expression was measured flow cytometrically by the binding of C219 or MRK16 monoclonal antibody to multidrug-sensitive human K562 erythroleukemia and 8226/S myeloma cells, compared to multidrug-resistant 8226/DOX40 myeloma cells. Cells were treated for up to 2 h with up to 80 units of leukoregulin/ml or one of a variety of unrelated cytokines including interleukin 1 alpha (IL-1 alpha), IL-1 beta, IL-2, IL-3, IL-4, IL-5, IL-6, colony-stimulating factor, macrophage colony-stimulating factor, granulocyte macrophage colony-stimulating factor, tumor necrosis factor alpha, gamma-interferon, alpha-interferon, epidermal growth factor, platelet-derived growth factor AA, platelet-derived growth factor BB, insulin-like growth factor I, insulin-like growth factor II, fibroblast growth factor, or transforming growth factor beta. Leukoregulin caused a concentration-dependent decrease in P-glycoprotein expression; however, P-glycoprotein expression was unaffected by the other cytokines (< 12% decrease in expression). Leukoregulin-induced membrane permeabilization, determined flow cytometrically by intracellular fluorescein efflux, and decreased P-glycoprotein expression occurred simultaneously within 15 min in drug-sensitive and -resistant cells. Enhanced doxorubicin uptake, measured flow cytometrically by doxorubicin influx, was also present within 15 min. Leukoregulin enhancement of doxorubicin uptake and increased membrane permeability varied directly with the decrease in P-glycoprotein expression. Leukoregulin in combination with doxorubicin enhanced the inhibition of cell proliferation in 8226/DOX40 multidrug-resistant cells over expressing P-glycoprotein. In contrast, combined treatment of HL-60/MX2 multidrug-resistant human promyelocytic leukemia cells that do not overexpress P-glycoprotein in association with their multidrug resistance resulted in no greater growth inhibition than observed with HL-60/MX2 cells treated with doxorubicin alone. This is the first demonstration that a naturally occurring macromolecule with anticancer activities can modulate the expression of P-glycoprotein concomitant with enhanced drug uptake and inhibition of cell proliferation. 相似文献
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SUMMARY Impotence is a common symptom which can cause considerable distress to both the sufferer and his partner. The use of pharmacotherapy to improve erectile function will continue to increase as safe and effective drugs are developed. However, restoring erectile function should not be the only treatment objective. It is also essential to address personal and emotional factors in the sufferer, conflicts in his relationship with his partner, and sexual problems in his partner, all of which may be instrumental in causing or maintaining the presenting impotence. We advocate a combined approach with appropriate medical treatment and sex and couple therapy 相似文献
49.
Strategies for treating pediatric malignancies have not only been successful (i.e., curative) for several disseminated childhood cancers, they have also served as paradigms for the therapy of many adult cancers. Initial strategies included combined treatment modalities (chemotherapy, surgery, radiotherapy) and combinations of different pharmacologic classes of anticancer drugs given in the appropriate schedules. Despite the currently successful therapy for some malignancies (e.g., 70% 4-year disease-free survival in acute lymphocytic leukemia), many children die without known reason. Recent advances in the clinical pharmacology of anticancer drugs have identified relationships between dose intensity and response (efficacy, toxicity). Traditional methods of measuring dose intensity (prescribed dose) have evolved to more sophisticated approaches in maximizing the intensity of treatment, with good response rates. Other methods of optimizing chemotherapy for individual patients include bone marrow support procedures and therapy with biologic response modifiers. Relatively few clinically useful new anticancer drugs have been discovered in the past several years. Fortunately, the potential to improve therapy with currently available agents has come about through enhanced knowledge of the biochemical and clinical pharmacology of anticancer drugs and biologic response modifiers, as well as improved understanding drug resistance biology. 相似文献
50.
This study investigated a discrete-trial, titration duration discrimination procedure in behavioral pharmacology. Pentobarbital and d-amphetamine, measured with this procedure, selectively affected discrimination more than response tendencies. Pentobarbital also tended to affect selectively discrimination of longer durations, whereas d-amphetamine did not. Further experiments showed that (1) other algorithms for modulating stimulus duration are useful in behavioral pharmacology and toxicology, (2) threshold estimates are similar with the method of constant stimuli and the method of titration, and (3) this titration procedure permits the separate examination of drug effects upon discrimination and upon response tendencies; the fixed-interval procedure does not. Baseline variability was an important correlate of drug effects in that the endpoints with more variable baselines were also more sensitive to drugs. 相似文献