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971.
Because of their widespread use, fragrances are among the most common causes of contact allergic dermatitis, second only to nickel. During a five-year period 3,065 patients with contact dermatitis were patch tested using a specific mix of fragrances. 509 (16.6%) patients were allergic to the fragrance mix, while 258 (8.4%) patients exhibited an allergic reaction to Myroxylon pereirae (balsam of Peru). Between those 509 patients, 157 were patch tested with eight individual substances contained in the fragrance mix: cinnamal, cinnamyl alcohol, eugenol, isoeugenol, geraniol, hydroxycitronellal, alpha-amyl cinnamal and Evernia prunastri (oak moss). The most frequent allergens were isoeugenol 57.9% (91/157), eugenol 55.4% (87/157), cinnamyl alcohol 34.4% (54/157) and Evernia prunastri (oak moss) 24.2% (38/157). There were 62 patients (39.5%) who exhibited an allergic reaction to both the fragrance mix and Myroxylon pereirae (balsam of Peru). The results prove the importance of avoiding allergens in daily life, especially in industrial and cosmetic products. In order to prevent ACD, better cooperation between industry and dermatologists is needed.  相似文献   
972.
Phototherapy denotes the use of ultraviolet (UV) light in the management of several dermatoses. Most phototherapy regimens utilize ultraviolet radiation of different wavelenghts. Currently, irradiations with broadband UVB (290-320 nm), narrowband UVB (311-313 nm), 308 nm excimer laser, UVA 1 (340-400 nm), UVA with psoralen (PUVA), and extracorporeal photochemotherapy (photopheresis) are being used. The interplay of the various photobiologic pathways is far from being completely understood. Disordes that may benefit from such approach are numerous, with psoriasis, atopic dermatitis, cutaneous T-cell lymphomas, morphea, and vitiligo as main indications. The immunomodulatory effects of UVB radiation primarily affect the epidermis and superficial dermis, while UVA radiation affects mid and deep dermal components, especially blood vessels. UVB radiation is absorbed by endogenous chromophores, such as nuclear DNA, which initiates a cascade of events. Absorption of UV light by nucleotides causes the formation of DNA photoproducts and suppresses DNA synthesis. In addition UV light stimulates synthesis of prostaglandins and cytokines that play important roles in immune suppression. It may reduce the number of Langerhans cells, cutaneous T lymphocytes and mast cells in the dermis. UV radiation can also affect extranuclear molecular targets located in the cytoplasm and cell membrane. Immune suppression, alteration in cytokine expression, and cell cycle arrest may all contribute to the suppression of disease activity. PUVA is a form of chemophototherapy which uses UVA light to activate chemicals known as psoralens, hence psoralen ultraviolet A. The conjunction of psoralens with epidermal DNA inhibits DNA replication and causes cell cycle arrest. Psoralen photosensitization also causes an alteration in the expression of cytokines and cytokine receptors. Psoralens interact with RNA, proteins and other cellular components and indirectly modify proteins and lipids via singlet oxygen-mediated reactions or by generating of free radicals. Infiltrating lymphocytes are strongly suppressed by PUVA, with variable effects on different T-cell subsets. Psoralens and UV radiation also stimulate melanogenesis. Extracorporeal photopheresis is technique used in treatment of erythrodermic cutaneous lymphomas. It is very potent in induction of lymphocyte apoptosis. Despite the introduction of numerous effective systemic medications and biologic agents in dermatology, phototherapy remains a reliable, and often preferred option for several dermatoses.  相似文献   
973.
Through the treatment of anaemia in dialysis patients part of the iron ions remain free in the serum which is at the bacterias disposal for growth and the strengthening of their virulence. The linear relation of the increased serum iron level and tissue iron stores in the body and the infection incidence in dialysed patients has become more emphasised. The need of a clearly defined upper threshold of the serum iron concentration limit has been mentioned in scientific journals intensely, and consequently the demand for more precise professional instructions for anaemia treatment. For the purpose of participating in these professional and scientific discussions, we have observed the relation between the iron overload of the organism and complication incidence in 120 of our haemodialysis uremic patients, with special emphasis on infections. It has been established that the sepses incidence is much higher in patients with a serum ferritin concentration above 500 microg/L, than in those patients with a ferritin level lower than the mentioned value ( 2 = 7.857, p = 0.005). The incidence of vascular access infection is significantly higher in those patients with a serum ferritin level above 500 microg/L than in those patients with a ferritin level lower than the mentioned value (Chi2 = 23.186, p = 0.001). Furthermore, it has been determined that the incidence of total infection in patients is 3.8 episodes per 100 patients months, which is in accordance to the referral values of other authors. CONCLUSION--In the analysis of the achieved results, it has been determined that the infection incidence is significantly higher in dialysed patients with a serum iron level higher than 500 g/L, than in those patients with lower values.  相似文献   
974.
Amniotic membrane transplantation (AMT) leads to reduction of inflammatory symptoms and causes faster epithelisation in corneal ulcers and persistant epithelial defect. 21 patients with corneal ulcer (n = 18) or non-healing epithelial defect (n = 3) unresponsive to conventional treatment were included in the study. All patients were treated by AMT. Corneal epithelial cells in patients suffering from corneal ulcer secreted 3.51 +/- 1.79 of IL-1alpha, 64.27 +/- 31.53 pg/mL of TNFalpha and 209.07 +/- 201.82 pg/mL of VEGF. Levels of all 3 investigated cytokines were significantly higher as compared to controls (p < 0.005). Amniotic membranes that were used contained 775.69 +/- 613.98 pg/mL of IL-1alpha, 0.036 +/- 0.033 pg/mL of sTNF and 175.01 +/- 166.63 pg/mL of VEGF-R. Supporting effect of the AMT could be explained by the fact that AM secretes its natural antinflammatory antagonists IL-1ra, sTNF and VEGF-R.  相似文献   
975.
The subjective investigation, that is focused on the sensations of a person, is a good tool for the evaluation of an environment that group of people consider comfortable. In the experiment reported here, participants were dressed into 1-layer and 2-layer clothing systems. They performed physical activity and rated the subjective perception of comfort, as well as the thermal and moisture sensation. The aim of this investigation is to compare the subjective human perception during the physical activity wearing different clothing systems to the objective results of sweat absorption.  相似文献   
976.
The aim of this study is to compare the effects of femoral analgesia (FA) with 0.25% levobupivacain and intravenous patient controlled analgesia (PCA) with morphine on postoperative pain assessed by a visual-analog scale (VAS) score and their complications during the first 24 postoperative hours after the a total knee arthroplasty in a prospective randomized study. Secondary outcomes included: morphine use, patient satisfaction, complication of analgesia and duration of hospital stay. We analyzed 71 patients with an ASA score of II or III. The patients were randomized into two groups: group PCA (n = 36) was given the PCA pump, which contained morphine; and group FA (n = 35) was given first a bolus dose, then a continuous infusion 0.25% levobupivacain via a femoral catheter. The assessment of VAS was performed every 2 hours. There were no differences between the PCA and FA groups regarding demographic characteristics, operation duration, ASA score distribution, duration of hospital stay and satisfaction with analgesia (although there were more satisfied patients in the FA group). Significant differences were noted in the quantity of morphine used (higher values were in the PCA group; p < 0.001). More complications were recorded in PCA group (p < 0.001). The VAS score was lower in the FA group (p < 0.001). The highest difference occurred 4 hours after the operation, with the PCA group having significantly higher VAS score values compared to the FA group. Femoral analgesia leads to a stronger pain relief with less side effects, less morphine use and more patient satisfaction than intravenous PCA with morphine.  相似文献   
977.
Determining a patient's prognosis after severe traumatic brain injury remains difficult and complex. The purpose of the present study was following up patients with severe traumatic brain injury by correlating their clinical outcome and sequential computer tomography (CT) findings. We investigated 51 patients who survived the first year following an accident. All patients underwent successive CT examinations within a maximum period of 2 years. The patients' outcomes depended on the underlying brain damage and are presented by the Glasgow Outcome Scale. Based on the investigated data we concluded that the worst outcomes were experienced by patients with initial massive cerebral edema, extensive subdural hematoma and intraventricular hemorrhage, followed by stroke as subacute CT finding and cerebral atrophy as chronic finding visible at follow-up CT scans. The majority of lesions identified by CT scan were found in the frontal lobes, basal ganglia, and temporal lobes. We suggest that CT examination still represents a simple and useful tool in attempting to predict the clinical outcome in patients with severe traumatic brain injury.  相似文献   
978.
Central corneal thickness is very important measurement in glaucoma treatment because it influences the eye pressure measurements. A thinner cornea gives us artifactually lower intraocular pressure and a thicker cornea gives higher intraocular pressure reading, so it has to be corrected in both cases. The aim of this study is to compare central corneal thickness between congenital glaucoma patients and normal subjects. Prospective study included 27 patients with congenital glaucoma and 35 patients in control group. First group was subdivided in two subgroups: A--8 earlier operated patients, B--19 patients treated with topic therapy. Patients had no other corneal disorders, history of trauma, corneal surgery and they were not contact lens wearers. Measurements were performed by specular microscope Tomey EM 3000 on central corneas. This study showed that patients with congenital glaucoma have lower central corneal thickness than normal subjects. Also, the study showed that antiglaucomatous operation doesn't influence central corneal thickness. Central corneal thickness need to be a routine part of examination measurements because of need to correct intraocular pressure according to it, but also the thinner corneas values can suggest congenital glaucoma diagnosis beside the other parameters.  相似文献   
979.
We investigated the relationship of efficiency in the application of the ESIN method of intramedullary osteosynthesis and other active surgical methods in the treatment of diaphyseal fractures of long bones in children and adolescents. The study comprised 100 subjects treated by elastic stable intramedullary osteosynthesis (ESIN - group A) and 50 subjects in whom other active surgical methods were applied (group B). The following criteria of efficiency of treatment were applied: 1. length of perioperative hospitalization, 2. time elapsed since the operation until the beginning of loading of the traumatized extremity, 3. time elapsed since the operation until the full loading of the extremity, i.e. until the recovery of the fracture, 4. incidence of complications, 5. number of post-operative outpatient clinical visits until the recovery of the fracture and 6. overall number of X-ray images of the fractured bone since the accident until the coalescence of the fracture. The results obtained in both groups were compared. 1. The length of perioperative hospitalization is shorter in patients in whom ESIN method was applied. The difference between arithmetic means was 4.45 days and is statistically significant (p < 0.001). 2. The time between the operation until the beginning of loading of the extremity is shorter in patients subjected to ESIN method of osteosynthesis, the difference of mean values being 23.49 days and is statistically significant (p < 0.001). 3. The time between the operation until the full loading of the extremity is shorter in patients subjected to ESIN method of osteosynthesis, the difference being 16.6 days and is statistically significant (p < 0.001). 4. The number of complications in patients treated by the ESIN method of osteosynthesis is not statistically different from that in group B (chi2 = 0.25, p = 0.62). 5. In postoperative period there were fewer outpatient controls in patients to whom ESIN method of osteosynthesis was applied, and the difference is statistically significant (Z = 7.69, p < 0.001). 6. Likewise, the overall number of X-ray controls was lesser (Z = 8.06, p < 0.001). The results of examining the above parameters point to a greater efficiency of treating diaphyseal fractures of long bones in children and adolescents by the ESIN method of osteosynthesis, compared to other active surgical methods.  相似文献   
980.
The purpose of this study was to compare the duration and variability of speech segments of children who stutter with those of children who do not stutter and to identify changes in duration and variability of speech segments due to the effect of utterance length. Eighteen children participated (ranging from 6.3 to 7.9 years of age). The experimental task required the children to repeat a single word in isolation and the same word embedded in a sentence. Durations of speech segments and Coefficients of variation (Cv) were defined to assess temporal parameters of speech. Significant differences were found in the variability of speech segments on the sentence level, but not in duration. The findings supported the assumption that linguistic factors pose direct demands on the speech motor system and that the extra duration of speech segments observed in the speech of stuttering adults may be a kind of compensation strategy.  相似文献   
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