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141.
Actinic reticuloid (AR) or chronic actinic dermatitis is considered a sunlight-induced pseudolymphoma (PSL) on light exposed areas of the skin, which primarily affects elderly males. The disease is a severe, chronic photosensitive dermatosis, first described by Ive et al. in 1969. PSL is a group of non-cancerous lymphocytic skin disorders that simulate malignant lymphomas, but the changes usually spontaneously regress. The clinical appearance of Actinic reticuloid is variable, usually characterized by an eczematous, pruritic eruption, predominantly present on the head and neck, or other sun exposed areas, but can involve any area of the body. Thereby, crucial characteristic is photosensitivity, where at action spectrum involves UVB, UVA and visible light beyond 400 nm. The disease is considered as PSL which histologically resembles lymphoma with immunohistochemical analysis of the cutaneous infiltrate revealing presence of activated T cells, numerous histiocytes, macrophages and B cells. Moreover, the development of malignant (non-cutaneous) T cell lymphoma in the course of AR has been reported. As the disease has chronic character, it requires significant changes in the patient's lifestyle and avoidance of provoking factors such as contact allergens or sources of intense light. Thus AR should be considered in every patient who presents with persistent, unclear, erythematous skin changes on the face and neck that are related to sun exposure.  相似文献   
142.
Incidence rate of skin tumours, both, non-melanoma and melanoma, is increasing nowadays. Various etiological factors are of relevance for the occurrence of the diseases. The solar radiation, as well, long-term exposure to ultraviolet (UV) radiation, have the greatest impact on development of these skin tumours. Non-melanoma skin tumours, Basal Cell Carcinoma (BCC) and Squamous Cell Carcinoma (SCC), are the most common skin tumours in humans, and usually develop on the chronically photo-exposed areas. As for the Malignant Melanoma (MM), one of the most aggressive skin tumours, the exposure to solar radiation also plays an important role. This study investigates the correlation between the skin tumours and UV radiation in the area of West Herzegovina, on the sample of 1676 patients. It presents the occurrence of skin tumours in the period from 1997 to 2003. The study investigates the incidence and the risk factors separately for every skin tumour which can be etiologically related to the occurrence of skin tumours and UV radiation: occupation, exposure to UV radiation, skin type, and family history on malignan tumours within the patient's family. The exact incidence rate of non-melanoma and melanoma skin tumours in Bosnia and Herzegovina is still unknown, for the reason that the united National Cancer Register does not exist yet.  相似文献   
143.
Brain lateralization is a common term used to describe dominance of one brain hemisphere over another for a specific function. The right hand dominance in writing, controlled by the left hemisphere, is preceded by development of communicative gesticulation and followed by development of speech in the same hemisphere. We assumed that some people are not aware of their own capability of using the other hand for tasks involving fine motor sequential movements. To prove this hypothesis, the participants were asked to perform one trained task (writing) and one less-trained task (drawing) with a dominant and a non-dominant hand. The final sample was comprised of 1189 children from 14 elementary schools and 8 high schools in the Osijek area, of which 685 elementary school children were attending 1st to 4th grade and 504 high school children were attending 3rd and 4th grade. The participants were asked to write two words, draw a specific object (a vase with flowers) and fill out a questionnaire with 10 questions concerning the classification of handedness and cerebral hemisphere dominance. The self-reported cerebral lateralization assessed in the questionnaire was compared with the drawing and the writing performance. The self-reported and objectively measured hand dominance deviated in the cases of the ambidextrous who consider themselves right-handers. Given the fact that the number of ambidextrous persons was greater in elementary schools than in high schools, we concluded how training of the right hand decreases the ability of using both hands equally for either of the tested functions - writing and drawing.  相似文献   
144.
The effects of spray-drying process and acidic solvent system on physicochemical properties of chitosan salts were investigated. Chitosan used in spray dryings was obtained by deacetylation of chitin from lobster (Panulirus argus) origin. The chitosan acid salts were prepared in a laboratory-scale spray drier, and organic acetic acid, lactic acid, and citric acid were used as solvents in the process. The physicochemical properties of chitosan salts were investigated by means of solid-state CP-MAS 13C nuclear magnetic resonance (NMR), X-ray powder diffraction (XRPD), differential scanning calorimetry, and Fourier transform infrared spectrometry (FTIR) and near-infrared spectroscopy. The morphology of spray-dried chitosan acid salts showed tendency toward higher sphericity when higher temperatures in a spray-drying process were applied. Analysis by XRPD indicated that all chitosan acid salts studied were amorphous solids. Solid-state 13C NMR spectra revealed the evidence of the partial conversion of chitosan acetate to chitin and also conversion to acetyl amide form which appears to be dependent on the spray-drying process. The FTIR spectra suggested that the organic acids applied in spray drying may interact with chitosan at the position of amino groups to form chitosan salts. With all three chitosan acid salts, the FTIR bands at 1,597 and 1,615 cm−1 were diminished suggesting that –NH groups are protonated. The FTIR spectra of all chitosan acid salts exhibited ammonium and carboxylate bands at 1,630 and 1,556 cm−1, respectively. In conclusion, spray drying is a potential method of preparing acid salts from chitosan obtained by deacetylation of chitin from lobster (P. argus) origin.  相似文献   
145.
Developmental hip dysplasia (DDH) greatly contributes to occurrence of severe hip osteoarthritis (OA) in adulthood, but the association between the two is not a perfect one. Both conditions are known to have a strong genetic component. Transforming growth factor β1 (TGF-β1) and interleukin-6 (IL-6) are two pro-inflammatory cytokines included in pathogenesis of OA, bone remodeling and development of bone and joint tissues. TGF-β1 gene has a polymorphic site in the signal sequence ((29)T→C) and "C allele carriage" is associated with higher circulating TGF-β1 levels. IL-6 gene has several polymorphic sites in the promoter region including -572T→C transition associated with higher circulating IL-6 levels. As a preliminary investigation on possible association between these polymorphisms and severe adult hip OA secondary to DDH, 28 consecutive patients and 20 healthy controls were genotyped at these loci. With adjustment for sex, "C allele carriage" in the TGF-β1 signal sequence and CC genotype ("transition homozygous") at locus -572 in the IL-6 promoter were each associated with severe OA secondary to DDH (OR=13.4, p=0.016 and OR=6.2, p=0.024, respectively). The combination of these genotypes was particularly strongly associated with the disease (OR=11.1, p<0.001). Data support feasibility of larger-scale studies on potential association between TGF-β1 signal sequence and IL-6 promoter polymorphisms and occurrence of DDH and (un)related severe OA.  相似文献   
146.
147.
Skeletal (striated) muscle is one of the four basic tissue types, together with the epithelium, connective and nervous tissues. Lungs, on the other hand, develop from the foregut and among various cell types contain smooth, but not skeletal muscle. Therefore, during earlier stages of development, it is unlikely that skeletal muscle and lung depend on each other. However, during the later stages of development, respiratory muscle, primarily the diaphragm and the intercostal muscles, execute so called fetal breathing-like movements (FBMs), that are essential for lung growth and cell differentiation. In fact, the absence of FBMs results in pulmonary hypoplasia, the most common cause of death in the first week of human neonatal life. Most knowledge on this topic arises from in vivo experiments on larger animals and from various in vitro experiments. In the current era of mouse mutagenesis and functional genomics, it was our goal to develop a mouse model for pulmonary hypoplasia. We employed various genetically engineered mice lacking different groups of respiratory muscles or lacking all the skeletal muscle and established the criteria for pulmonary hypoplasia in mice, and therefore established a mouse model for this disease. We followed up this discovery with systematic subtractive microarray analysis approach and revealed novel functions in lung development and disease for several molecules. We believe that our approach combines elements of both in vivo and in vitro approaches and allows us to study the function of a series of molecules in the context of lung development and disease and, simultaneously, in the context of lung's dependence on skeletal muscle-executed FBMs.  相似文献   
148.
Concentrations of lindane from adipose tissue i.e. omentum of sheep from homesteads of island Krk that were treated with lindane, were compared with the concentrations of lindane measured in adipose tissue of non treated sheep from husbandry cooperative on island Cres. Evaluation of food safety for this samples were estimated by comparing obtained results and maximum tolerance concentration (MTC) for lindane (2.0 and 0.2 mg/kg). In treated lambs from Krk measured concentrations of lindane were in range from 0.0038 to 1.8644 mg/kg, and in treated sheep from 0.0094 to 1.646 mg/kg. In control group of lambs and sheep concentration of lindane was < or = 0.0051 mg/kg. Estimation of food safety based on the results from this research are discussable, regarding the fact that MTC prescribed before year 2007 was 2.0 mg/kg. When the new law Regulations of MTC for residues of pesticides in food and animal feed (NN 119/07) came into the force prescribed MTC was 0.02 mg/kg. If food safety of sheep meat from Krk would be estimated based on latter, then 73.4% of samples of lamb meat and 80% of sheep meat could be proclaimed unsafe for human consumption. It is encouraging that after completion of using lindane in year 2005, levels of lindane in adipose tissue of lamb from Krk in year 2006 were under the concentration set by new legislate (< 0.02 mg/kg).  相似文献   
149.
Increased glutaminolysis is now recognized as a key feature of the metabolic profile of cancer cells, along with increased aerobic glycolysis (the Warburg effect). In this review, we discuss the roles of glutamine in contributing to the core metabolism of proliferating cells by supporting energy production and biosynthesis. We address how oncogenes and tumor suppressors regulate glutamine metabolism and how cells coordinate glucose and glutamine as nutrient sources. Finally, we highlight the novel therapeutic and imaging applications that are emerging as a result of our improved understanding of the role of glutamine metabolism in cancer.  相似文献   
150.
Current clinical brain imaging techniques used for surgical planning of tumor resection lack intraoperative and real‐time feedback; hence surgeons ultimately rely on subjective evaluation to identify tumor areas and margins. We report a fluorescence lifetime imaging (FLIm) instrument (excitation: 355 nm; emission spectral bands: 390/40 nm, 470/28 nm, 542/50 nm and 629/53 nm) that integrates with surgical microscopes to provide real‐time intraoperative augmentation of the surgical field of view with fluorescent derived parameters encoding diagnostic information. We show the functionality and safety features of this instrument during neurosurgical procedures in patients undergoing craniotomy for the resection of brain tumors and/or tissue with radiation damage. We demonstrate in three case studies the ability of this instrument to resolve distinct tissue types and pathology including cortex, white matter, tumor and radiation‐induced necrosis. In particular, two patients with effects of radiation‐induced necrosis exhibited longer fluorescence lifetimes and increased optical redox ratio on the necrotic tissue with respect to non‐affected cortex, and an oligodendroglioma resected from a third patient reported shorter fluorescence lifetime and a decrease in optical redox ratio than the surrounding white matter. These results encourage the use of FLIm as a label‐free and non‐invasive intraoperative tool for neurosurgical guidance.  相似文献   
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