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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.
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   
5.
Over the past decade extracorporeal shock-wave therapy (ESWT) has been increasingly applied to orthopaedic and musculoskeletal pathologies, the aim of this study was to assess how the energy density of the shock waves and the number of impulses affect viability, differentiation and synthetic activity of osteoblasts. Primary sheep osteoblasts cultures were treated with ESWT with an electro-hydraulic shock wave generator by selecting three different energy levels (14-21-28 kV corresponding at 0.15-0.31-0.40 mJ/mm2) and two different total numbers of impulses (500, 1000) for each level. At the end of treatment, cell counts and viability were recorded. Cells were then cultivated for 48 hours starting from a concentration of 1 x 10(4) cells/ml. The biological activity and viability were evaluated at 24 and 48 hours after treatment. No cytodestructive effects were observed in Group A, while a cytodestructive effect of ESWT was seen in cultures receiving the highest energy treatments. The different shock wave treatment induced differences in MTT assays after 24 and 48 hours, in particular the highest level showed a detrimental effect on cell respiration at both experimental times as compared to the Control Group and the protein metabolism was generally depressed by ESWT with impulses at the highest energy level. After 24 hours such effect further increased with the growing number of impulses. The lowest energy level appeared to significantly improve the metabolic parameter in primary cell cultures as compared to controls when 500 impulses were selected. The current study has demonstrated that one of the most important aspects to be considered is not the total number of impulses used but the energy level of the shock waves, thus confirming that ESWT has a dose-dependent effect on cells.  相似文献   
6.
The biological properties of a composite polymeric matrix (PMMA + alpha-TCP) made of polymethylmethacrylate (PMMA) and alfa-tricalciumphosphate (alpha-TCP) was tested by means of in vitro and in vivo investigations. PMMA was used as a comparative material. Osteoblast cultures (MG 63) demonstrated that PMMA + alpha-TCP significantly and positively affected osteoblast viability, synthetic activity and interleukin-6 level as compared to PMMA. At 12 weeks, the PMMA + alpha-TCP implants in rabbit bone successfully osteointegrated in trabecular and cortical tissue (affinity index: 57.14+/-8.84% and 68.31+/-6.18%, respectively). The newly formed bone after tetracycline labelling was histologically observed inside PMMA + alpha-TCP porosity. The microhardness test at the bone-PMMA + alpha-TCP interface showed a significantly higher rate of newly formed bone mineralization compared with PMMA (+83.5% and +58.5%, respectively), but differences still existed between newly formed and pre-existing normal bone. It is herein hypothesized that the present positive results may be ascribed to the porous macroarchitecture of PMMA + alpha-TCP and the presence of the bioactive ceramic material that could have a synergic effect and be responsible for the improvement of (a) the material colonization by bone cells, (b) osteoblast activity, (c) osteoinduction and osteoconduction processes, (d) bone remodelling.  相似文献   
7.
Osteointegration of yttria stabilised tetragonal zirconia (YSTZ), either coated with bioactive glass named RKKP bioglaze (RKKP) or uncoated, was evaluated in an animal model. RKKP-coated and uncoated (controls) YSTZ cylinders were implanted in the distal femoral epiphyses of 14 Sprague Dawley rats under general anaesthesia. At the experimental times of 30 and 60 days after sacrifice, histomorphometry and SEM microanalysis were performed on methylmethacrylate-embedded undecalcified sections to determine the osteointegration rate. At 30 days, a significantly higher affinity index was demonstrated in vivo by histomorphometric evaluation in RKKP-coated versus uncoated YSTZ implants p < 0.05); at 60 days, the coated implants behaved better than controls (affinity index of + 32%), but the difference observed lay within the statistical uncertainty. SEM analysis demonstrated better bone adhesion to the material in RKKP-coated YSTZ at both 30 and 60 days. These findings suggest that YSTZ coated with the bioactive glass named RKKP enhances osteointegration of ceramics.  相似文献   
8.
To study the presence of metals in body fluids and tissues after implantation of metallic biomaterials and possible related diseases, a new approach in Atomic Absorption Spectrophotometry (AAS) was developed. This technique was compared to three traditional methods: mineralisation with acid digestion (method A) also known as "wet method", dry ashing (with or without oxygen) (method B); classic Kjeldaal (method C). The new approach (method D) modifies the mineralisation phase and the instrument operating instructions. Al, Na, Cr, K, Ni, Co, Ti, Fe, Hg, Pb, V, Sb and Cu levels were tested with the four methods on bone, muscle, cartilage, skin, brain, lymph nodes, blood, urine, and hair. Test results were checked by the addition method. Results demonstrated a significantly higher percentage of Al, Cr, Ni, Ti and Hg recovery with the new approach. The advantages of method D are no residue, no redox reaction, insignificant loss of analytes and enhanced sensitivity (at ppb level vs ppm of the other methods). This approach should be considered especially when testing heavy metals and complex matrices. Its disadvantages are that it is more time consuming and requires the presence of an operator.  相似文献   
9.
In rats the effects of chronic treatment with thioridazine (5 mg/kg orally administered for 22 days) were studied by means of behavioural supersensitivity to apomorphine and by means of dopamine (DA) receptors quantitative autoradiography. Locomotion and stereotypies induced by apomorphine increased after thioridazine chronic administration, whereas grooming behaviour decreased. Autoradiographic data showed an increase in DA receptors density both in the striatum and in the olfactory tubercle, to which the increase in stereotypies and locomotion could be respectively attributed. DA receptors increased also in the medial and dorsal frontal cortex. Moreover a decrease in DA receptors density appeared in the nucleus accumbens septi and in the lateral frontal cortex. Receptors decrease found in these regions might be associated with thioridazine-induced chronic inactivation of A10 DA neurons, to which the antipsychotic effect of the drug is attributed.  相似文献   
10.
In this study, we tested a new square wave microprocessor-controlled red laser with an extremely low peak power output (<3 mW; very low level laser therapy [vLLLT]) in experimental pain in the rat. Acute inflammation was induced by intraplantar injection of carrageenan, chronic inflammation was induced by complete Freund's adjuvant (CFA) and neuropathic pain was produced by sciatic nerve chronic constriction injury (CCI). In our study vLLLT was effective in reducing edema and hyperalgesia in acute and chronic inflammation if administered at the points usually selected for acupuncture. Moreover, spontaneous pain and thermal hyperalgesia were reduced in CCI rats treated with vLLLT In conclusion, vLLLT reduced edema and induced analgesia in experimental plantar pain in rats. We interpret this to mean that enkephalin mRNA level was strongly upregulated in the external layers of the dorsal horn of the spinal cord in CFA and CCI animals, and that vLLLT further increased the mRNA level in single neurons.  相似文献   
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