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1.
Background/aim  Theoretical considerations support the combination of cryosurgery and topical imiquimod to treat basal cell carcinomas (BCC). The aim of the present study was to test the feasibility and efficacy of 'cryosurgery during continued imiquimod application' ('immunocryosurgery') to treat 'high-risk-for-recurrence' BCCs.
Methods  Thirteen patients with 21 biopsy-proven tumours (4 of 21 relapses after prior surgery) were included. After 2–5 weeks (median, 3) of daily 5% imiquimod cream application, the tumours were treated by liquid N2 cryosurgery (spray, two cycles, 10–20 s) and imiquimod was continued for additional 2–12 weeks (median, 4). The outcome after at least 18 months of follow-up (18–24 months) is currently reported.
Results  Nineteen of 21 tumours responded promptly to immunocryosurgery; two tumours required additional treatment cycles to clear. Thus, the clinical clearance rate was 100%. Only 1 of 21(5%) tumour relapsed after at least 18 months of follow-up (cumulative efficacy: 95%).
Conclusions  'Immunocryosurgery' is a promising non-surgical combination modality to treat 'high-risk-for-recurrence BCCs'. Initial evidence is suggestive of an at least additive effect of the two combined modalities. Further studies comparing immunocryosurgery directly with cryosurgery and imiquimod monotherapies will confirm the reported results.  相似文献   
2.
We studied blood pressure and natriuretic responses to acute salt loading, and the effect of non-steroidal anti-inflammatory agents on these responses, in five healthy normotensive women aged 65 to 71 years. Five women aged 25 to 31 years acted as controls. Intravenous saline loading, with and without prior ingestion of ibuprofen, was 15 ml/kg/h for 3 h. Baseline blood pressures were higher in the elderly. Saline infusion without ibuprofen raised systolic blood pressure (SBP) by about 25 mmHg in the older group only. Ibuprofen increased baseline SBP in the elderly (129 +/- 6 vs. 116 +/- 5 mmHg, p < 0.05). Saline loading after ibuprofen again raised blood pressure by about 25 mmHg in the elderly only. The elderly group showed markedly increased sodium excretion during saline loading, but this was reduced by ibuprofen. Ibuprofen had no effect on SBP or sodium excretion in controls. Ageing appears to increase susceptibility to salt retention and hypertension from non-steroidal anti-inflammatory agents.   相似文献   
3.
Uroscopy in the 21st century: high-field NMR spectroscopy   总被引:1,自引:1,他引:0  
From the experiments described, it can be seen that there are different research approaches that can be taken and these are summarized in Table 1. Whereas much scientific research is principally hypothesis led, there remains, nevertheless, an important place for exploratory research. High resolution NMR can measure, directly and simultaneously, a wide range of endogenous metabolites in biological fluids and has the unique capability of providing structural information on the metabolites detected. It has proved to be a powerful research tool with which to study inherited metabolic diseases, renal disease, drug metabolism, and toxicity, and can be used to monitor the effects of drug therapy. For instance, by using a library of experimental toxins one can map the metabolic profile of site-specific nephron injury. With this approach in man one could eventually take an unknown disease such as Balkan nephropathy and predict the initial site of tubular injury, the mode of injury and therefore the kind of toxin capable of producing that injury. NMR spectroscopic techniques are still advancing rapidly, with ever increasing sensitivity and sophistication of NMR pulse sequences to enhance structural elucidation in complex mixtures. Given the advances in directly coupled HPLC-NMR and even HPLC-NMR-mass spectroscopy it is likely that these technologies in conjunction with pattern recognition will make major contribution to our understanding of renal processes and provide new diagnostic insights in the 21st century.   相似文献   
4.
With one billion people overweight worldwide, the need to identify risk factors and treatments for obesity is urgent. The present study determined whether rats genetically prone to diet-induced obesity (DIO) show preexisting differences in meal microstructure and are sensitive to central anorectic effects of corticotropin-releasing factor type 2 (CRF2) receptor stimulation. Male, selectively bred DIO rats and their diet resistant (DR) counterparts ( n = 9/genotype) were weaned onto low-fat chow and compared as young adults for spontaneous or intracerebroventricular urocortin 2 administration-induced (0, 0.3, 1, 3 μg) differences in ingestion. DIO rats were hyperphagic selectively at the dark cycle onset, showing shorter latencies to initiate feeding, faster returns to eating following meal completion, and a lower satiety ratio than DR rats. At other times, DIO rats had briefer postmeal intervals, but ate smaller and briefer meals, resulting in normal intake. DIO rats also ate faster than DR rats. Urocortin 2 was less potent in DIO rats, ineffective at the 0.3 μg dose, but produced CRF2 antagonist-reversible anorexia at higher doses. Though heavier, chow-maintained DIO rats were proportionately as or more lean than DR rats. Thus, DIO rats showed signs of a preexisting, heritable deficit in the maintenance of postmeal satiety and a reduced sensitivity to anorectic CRF2 agonist stimulation. The meal patterns of DIO rats temporally resemble human 'snacking' behaviour, which predicts adult obesity. Because central CRF2 stimulation retains full anorectic efficacy at higher doses in the DIO model, manipulating this neuropeptidergic system might yield new therapeutic approaches for diet-induced obesity.  相似文献   
5.
Autosomal dominant cerebellar ataxia with progressive macular degeneration is caused by a CAG/glutamine repeat expansion in the SCA7 gene/protein. Neuronal intranuclear inclusions were detected in the brain of an early onset SCA7 case with the 1C2 antibody directed against an expanded polyglutamine domain. Nuclear inclusions were most frequent in the inferior olivary complex, a site of severe neuronal loss in SCA7. They were also observed in other brain regions, including the cerebral cortex, not considered to be affected in the disease. Using confocal microscopy we showed that some inclusions were ubiquitinated, but to varying degrees, ranging from <1% in the cerebral cortex to 60% in the inferior olive. In addition, we also observed cytoplasmic staining using the 1C2 antibody, particularly in the supramarginal gyrus, the hippocampus, the thalamus, the lateral geniculate body and the pontine nuclei. These data confirm that the presence of intranuclear inclusions in neurons is a common characteristic of disorders caused by CAG/polyglutamine expansions, but unlike what has been reported for Huntington's disease, SCA1 and SCA3/MJD, in SCA7 the inclusions were not restricted to the sites of severe neuronal loss.   相似文献   
6.
During a winter training season, the effects of 12 weeks of intense training and 4 weeks of tapering off (taper) on plasma hormone concentrations and competition performance were investigated in a group of highly trained swimmers (n = 8). Blood samples were collected and the swimmers performed their speciality in competition at weeks 10 (mid-season), 22 (pre-taper) and 26 (post-taper). No statistically significant changes were observed in the concentrations of total testosterone (TT), non-sex hormone binding globulin-boundtestosterone (NSBT), cortisol (C), luteinising hormone, thyroid stimulating hormone, triiodothyronine, thyroxine plasma catecholamines, creatine kinase and ammonia during training and taper. Mid-season NSBT: C ratio and the amount of training were statistically related (r = 0.82,P < 0.05). Competition performance slightly declined during intense training [0.52 (SD 2.51) %, NS] and improved during taper [2.32 (SD 1.69)%,P < 0.01]. Changes in performance during training and taper correlated with changes in ratios TT: C (r = 0.86,P < 0.01andr = 0.81,P < 0.05, respectively) and NSBT: C (r = 0.77,P < 0.05 andr = 0.76,P < 0.05, respectively). In summary, these results showed that the monitored plasma hormones and metabolic indices were unaltered by 12 weeks of intense training and 4 weeks of taper. The TT: C and NSBT: C ratios, however, appeared to be effective markers of the swimmers' performance capacities throughout the training season.  相似文献   
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PURPOSE: The epidermal growth factor receptor (EGFR) may play a relevant role in the progression, hormone therapy resistance, and prognosis of prostate cancer patients. Also MDM2, a negative p53 regulator that interacts with retinoblastoma (Rb), E2F, p19(arf) and the ras-mitogen-activated protein kinase(MAPK) cascade plays an important role in prostate cancer progression and prognosis. On the basis of the EGFR and MDM2 role in integrating signaling pathways critical for prostate cancer progression, we investigated whether their selective combined blockade may have a cooperative antitumor effect in prostate cancer. For this purpose, we have used the EGFR tyrosine kinase inhibitor gefitinib (ZD1839, Iressa) and a second generation hybrid oligonucleotide antisense MDM2 (AS-MDM2), respectively. EXPERIMENTAL DESIGN: Gefitinib and AS-MDM2 were administered to hormone-refractory and hormone-dependent human prostate cancer cells in vitro and to mice bearing tumor xenografts, evaluating the effects on growth, apoptosis, and protein expression, in vitro and in vivo. RESULTS: We demonstrated that the combination of gefitinib and AS-MDM2 synergistically inhibits the growth of hormone-independent prostate cancer cells in vitro. This effect is accompanied by the inhibition of MDM2, phosphorylated Akt (pAkt), phosphorylated MAPK (pMAPK), and vascular endothelial growth factor (VEGF) expression and by Rb hypophosphorylation. The combination of the two agents in nude mice bearing the same hormone-independent tumors caused a potent cooperative antitumor effect. Tumor samples analysis confirmed the inhibition of MDM2, pAkt, pMAPK, VEGF, and basic fibroblast growth factor expression. CONCLUSIONS: This study shows that EGFR and MDM2 play a critical role in the growth of prostate cancer, especially hormone-dependent, and that their combined blockade by gefitinib and AS-MDM2 causes a cooperative antitumor effect, supporting the clinical development of this therapeutic strategy.  相似文献   
10.
Thyroid dysfunction can develop in patients with Hodgkin's disease who are treated with mantle irradiation. During the period 1970-89, the records of 320 patients who received mantle irradiation and who had thyroid function tests (TFT) were retrospectively reviewed. The median age was 30 years (range, 7-69 years). The median mantle and thyroid dose was 36 Gy (range, 30-40 Gy) and 39.8 Gy (range, 32-65 Gy), respectively. Overall thyroid dysfunction was present in 39% of the patients. Clinical hypothyroidism was seen in 10% and biochemical hypothyroidism was noted in 25%. Hyperthyroidism was found in 4% of patients. Thyroid nodules had developed in six patients (2%), of which those in four patients were malignant. Age, sex, histological subtype, stage of disease, dose, lymphangiogram and treatment with chemotherapy were not significant factors in the development of thyroid dysfunction. The narrow dose range prevented adequate analysis of dose effect. The results indicate that the incidence of thyroid abnormalities is high enough to warrant regular TFT assessment with pre-irradiation levels and follow-up testing for life because the development of abnormalities can occur many years later. Thyroid examination should form part of the routine follow-up examination and any abnormality should be promptly investigated.  相似文献   
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