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1.
Patch testing was carried out in 851 atopic patients; 181 atopic dermatitis (AD) patients were additionally tested with 50% dilutions of the test substances. The occurrence of allergic and irritant reactions was frequent, being 57% and 33% for AD patients aged 28-41 years and 19-27 years, respectively. Among age-matched allergic rhinitis (AR)/allergic conjunctivitis (AC) or asthma (A) patients, the number of allergic reactions varied from 25 to 30%, and for irritant reactions was 24%. In all groups, nickel, fragrance-mix, balsam of Peru and neomycin were the commonest allergens. Contact allergy to ingredients of topical medicaments was common among AD patients and patients with severe and long-lasting dermatitis were most frequently sensitized. However, sensitivity to multiple substances was not common among those patients. The number of irritant reactions was considerable, but 50% dilution of the test substances did not solve the problem.  相似文献   
2.
慢性肝病、原发性肝癌病人血清、肝组织纳米细菌的检测   总被引:4,自引:0,他引:4  
目的 研究慢性肝病和原发性肝癌病人血清、组织中纳米细菌(NB)感染,为其发生机制提供新的认识。方法 55例慢性肝病(25例慢性乙肝和30例肝炎后肝硬化)、43例肝癌病人和336例健康人血清采用ELISA、免疫组化和钙染色;53例慢性肝病(28例慢性乙肝和25例肝硬化)、43例肝癌和15例对照肝组织行免疫组化染色,部分阳性组织透射电镜观察。结果 (1)慢性肝病、肝癌病人和健康人血清ELISA检测阳性率分别为20.0%、9.3%和8.0%,慢性肝病NB感染率高于健康人(P〈0.05)。免疫组化染色感染率分别为14.5%、4.7%和5.7%(P〈0.05)。钙染色分别为7.3%、4.7%和6.5%(P〉0.05)。(2)慢性肝病、癌及癌旁、对照组免疫组化阳性率分别为:20.8%、16.3%、14.0%和0%(P〉0.05)。部分肝癌和癌旁组织透射电镜观察发现纳米细菌样微生物结构(3/5)。结论 部分慢性肝病、肝癌病人血清、组织中存在纳米细菌感染,慢性肝病血清中纳米细菌感染率高于健康人。  相似文献   
3.
Background: Acetaminophen (paracetamol) is widely used for postoperative analgesia. Its mechanism of action is inhibition of prostaglandin synthesis in the central nervous system, and acetaminophen is traditionally not considered to influence platelet function. The authors studied the dose-dependent inhibition of platelet function by acetaminophen in healthy volunteers.

Methods: Thirteen healthy male volunteers (aged 19-26 yr) were given placebo or 15, 22.5, or 30 mg/kg acetaminophen intravenously in a double-blind, crossover study. Ten and 90 min after infusion, platelet function was assessed by photometric aggregometry and by measuring release of thromboxane B2, analgesia by cold pressor test, and plasma acetaminophen concentrations by high-performance liquid chromatography.

Results: When triggered with 500 [mu]m arachidonic acid, median platelet aggregation (area under the curve) was 25.7, 22.8, 4.1, or 3.6 x 103 area units (P < 0.001) 10 min after placebo or 15, 22.5, or 30 mg/kg acetaminophen, respectively. An increasing concentration of arachidonic acid attenuated the antiaggregatory effect. After 90 min, platelet function was recovering. Release of thromboxane B2 was also dose-dependently inhibited by acetaminophen. Although plasma concentration of acetaminophen increased linearly with the dose, no analgesic effect was detected in the cold pressor test.  相似文献   

4.

Background  

Movement control dysfunction [MCD] reduces active control of movements. Patients with MCD might form an important subgroup among patients with non specific low back pain. The diagnosis is based on the observation of active movements. Although widely used clinically, only a few studies have been performed to determine the test reliability. The aim of this study was to determine the inter- and intra-observer reliability of movement control dysfunction tests of the lumbar spine.  相似文献   
5.
The purpose of this study was to assess if chronic low back pain patients have impaired paraspinal muscle O2 turnover and endurance capacity as compared to healthy control subjects during dynamic exercise. Middle-aged healthy male subjects (n = 12, control) and male patients with chronic low back pain (n = 17, CLBP) participated in the study. L4–L5 level paraspinal muscle fatigue was objectively assessed during earlier validated 90 s dynamic back endurance test (spectral EMG, MPFslope). Also EMG amplitude (EMGamplitude) and initial MPF (MPFinitial) were assessed from the initial 5 s of the endurance contraction. Simultaneously near infrared spectroscopy (NIRS) was used for quantitative measurement of local L4–L5 paraspinal muscle O2 consumption. Subcutaneous tissue thickness (ATT) was measured from the EMG and NIRS recording sites. The results indicated that control and CLBP groups were compatible as regarding anthropometric variables, paraspinal muscle activation levels (EMGamplitude), initial MPF (MPFinitial) and ATT. When the ATT was used as a covariate in the ANOVA analysis, CLBP group did not show significantly greater paraspinal muscle fatigability (right MPFslope – 12.2 ± 10.7%/min, left right MPFslope – 12.6 ± 13.3%/min) or O2 consumption (right NIRSslope – 52.8 ± 79.6 μM/l/s) as compared to healthy controls (right MPFslope – 11.9 ± 7.6%/min, left MPFslope – 12.7 ± 8.6%/min, right NIRSslope – 53.7 ± 95.2 μM/l/s). As a conclusion, these CLBP male patients did not show any impaired rate of paraspinal muscle oxygen consumption or excessive paraspinal muscle fatigability during dynamic exercise as compared with healthy controls. Subcutaneous tissue thickness has a strong influence on the NIRS and EMG amplitude measurements and, if unchecked, it could result in the false interpretation of the results.  相似文献   
6.
Interaction of nanobacteria with cultured mammalian cells   总被引:11,自引:0,他引:11  
Nanobacteria were recently isolated from human blood and commercial fetal bovine serum (FBS) and were located in the -2 subgroup of proteobacteria based upon their 16S rRNA gene sequence. They can be cultured even in the absence of mammalian cells, and have extraordinary properties, like very slow growth rate and an impermeable cell wall, making their detection difficult by standard microbiological techniques. Since they are present in FBS, and thus in cell cultures, it is essential to clarify their effects on cultured mammalian cells. In this study, we show that four out of six nanobacterial isolates from different sera exerted a cytotoxic effect on 3T6 fibroblasts verified by MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide] viability assay, lactate dehygrogenase (LDH) release and by direct microscopy. The cytotoxic effect of nanobacteria was attenuated after they had been subcultured several times. The cytotoxic effect was similar with all tested murine and human fibroblastoid cell lines. Differential interference contrast and electron microscopy, and FITC staining with specific monoclonal antibodies indicated selective, possibly receptor-mediated adherence, followed by internalization and cytotoxicity in the 3T6 fibroblasts used as a model in these interaction studies. Thus, nanobacteria have a special way of invading mammalian cells: they trigger cells that are not normally phagocytic to engulf them. These organisms seem to be an important cause for cell vacuolization, poor thriving and unexpected cell lysis, problems frequently encountered in mammalian cell culture.  相似文献   
7.
Human epidermis contains a low molecular weight SH-protease inhibitor (Human Epidermal Inhibitor = HEI), whose epidermal localization was performed with the indirect immunofluorescence method. The fluorescence was most intensive in the cytoplasms of epidermal cells, often occurring perinuclearly. The fluorescent material in the frozen sections was often finely granular and occasionally extended outside the cytoplasm, while the fluorescence in fixed sections was more uniform, but weaker. Stratum basale generally stained poorly or not at all, as did also stratum lucidum. Stratum corneum stained fairly intensively throughout. In addition to fixation, the outcome of staining was also affected by the thickness of the epidermis, particularly stratum corneum. The significance of this inhibitor for the differentiation of epidermal cells and the keratinization of epidermis has therefore been discussed, and the authors assume it to be of considerable significance in these processes.  相似文献   
8.
The occurence of the human and rat epidermal SH-protease inhibitors in various human and rat tissues was studied by double radial immunodiffusion against specific antisera to the inhibitors. An immunoreactive protein was found in the extracts prepared from human and rat epidermis and from eosophageal and vaginal squamous epithelia, and from rat pro-ventricular squamous epithelium. No immunoreactive protein was found in man or rat in any other of their tissues, studied by us. The results strongly suggest that a protein reminiscent of the human or rat epidermal SH-protease inhibitor is present in squamous epithelia but not in other tissues. The identity of the epidermal inhibitor and the immunoreactive protein in the other squamous epithelia was confirmed by immunodiffusion, immunoelectrophoresis and gel chromatography, and by immunoinhibition of the papain inhibiting activity of the human epidermal and oesophageal inhibitors by gammaglobulins separated from antiserum to the human epidermal inhibitor.  相似文献   
9.
The present study investigates the effects of alpha 2-drugs and pilocarpine on the neocortical high-voltage spindle (HVS) activity in young and aged control and DSP4-lesioned rats. DSP4 partially decreased cortical and thalamic noradrenaline levels, but had no effect on HVS activity. The alpha 2-adrenoceptor agonist guanfacine (0.004, 0.02, 0.1 mg/kg) increased HVS activity in young and aged control and DSP4-lesioned rats. Guanfacine produced a significantly smaller increase in HVS activity in aged rats. A combination of pilocarpine (3 mg/kg), a muscarinic agonist, and atipamezole (1 mg/kg), an alpha 2-adrenoceptor antagonist, suppressed HVS activity more effectively than either of the drugs alone in young or aged control and DSP4-lesioned rats. The present results demonstrate that 1) the alpha 2-adrenoceptor antagonist and muscarinic agonist interact in suppressing HVSs in noradrenergically lesioned young and aged rats; 2) alpha 2-adrenoceptor agonists produce a greater increase in HVS activity in young than aged rats; and 3) partial noradrenergic lesions do not affect the HVS-modulating effects of alpha 2-adrenoceptor active drugs in young or aged rats.  相似文献   
10.
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