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1.
Radiodermatitis is one of the commonest side effects of radiotherapy. They are usually assessed by semi‐quantitative clinical scores, which are not validated and may be subject to inter‐observer variability. A few previous studies suggested that high‐frequency ultrasonography (HF‐USG) is useful in the assessment of the acute phase of radiation dermatitis in breast cancer patients. (a) To monitor skin changes by HF‐USG during the course of radiotherapy due to head and neck cancers, and (b) to determine whether there is any connection between skin sonograms and the skin scoring criteria. This prospective, observational study includes patients diagnosed with head and neck cancers, treated with radiotherapy or concomitant chemoradiation. The final analysis includes six patients. In every patient, the HF‐USG as well as dermatological assessment (target lesion score—TLS and CACE v. 4.0) were performed 4×: before, in the middle, day after, and 3 months after radiotherapy. There were significant differences between non‐irradiated skin thickness and thickness of skin with clinically obvious radiodermatitis (TLS grade 1‐4; P < .0001), as well as between irradiated, unchanged skin thickness (TLS grade 0) and thickness of skin with clinically obvious radiodermatitis (TLS grade 1‐4; P = .0002). There was no significant difference between non‐irradiated and irradiated, unchanged skin thickness (TLS grade 0; P = .9318). In four patients, we demonstrated subepidermal low echogenic band (SLEB). HF‐USG can be useful tool to noninvasive and objective assessment of skin changes during radiotherapy.  相似文献   
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Objective: Polyunsaturated fatty acids n-3 (PUFA n-3) have shown effects in reducing tumor growth, in particular eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) abundantly present in fish oil (FO). When these fatty acids are provided in the diet, they alter the functions of the cells, particularly in tumor and immune cells. However, the effects of α-linolenic fatty acid (ALA), which is the precursor of EPA and DHA, are controversial. Thus, our objective was to test the effect of this parental fatty acid. Methods: Non-tumor-bearing and tumor-bearing Wistar rats (70 days) were supplemented with 1 g/kg body weight of FO or Oro Inca® (OI) oil (rich in ALA). Immune cells function, proliferation, cytokine production, and subpopulation profile were evaluated. Results: We have shown that innate immune cells enhanced phagocytosis capacity, and increased processing and elimination of antigens. Moreover, there was a decrease in production of pro-inflammatory cytokines (tumor necrosis factor-alpha (TNF-α) and interleukin 6 (IL-6)) by macrophages. Lymphocytes showed decreased proliferation capacity, increased cluster of differentiation 8 (CD8+) subpopulation, and increased TNF-α production. Conclusions: Oil rich in ALA caused similar immune modulation in cancer when compared with FO.  相似文献   
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Classical Kaposi sarcoma (KS) usually appears on lower extremities accompanied or preceded by local lymphedema. However, the development in areas of chronic lymphedema of the arms following mastectomy, mimicking a Stewart–Treves syndrome, has rarely been described. We report an 81‐year‐old woman who developed multiple, erythematous to purple tumors, located on areas of post mastectomy lymphedema. Histopathological examination evidenced several dermal nodules formed by spindle‐shaped cells that delimitated slit‐like vascular spaces with some red cell extravasation. Immunohistochemically, the human herpesvirus type 8 (HHV‐8) latent nuclear antigen‐1 was detected in the nuclei of most tumoral cells confirming the diagnosis of KS. Lymphedema could promote the development of certain tumors by altering immunocompetence. Although angiosarcoma (AS) is the most frequent neoplasia arising in the setting of chronic lymphedema, other tumors such as benign lymphangiomatous papules (BLAP) or KS can also develop in lymphedematous limbs. It is important to establish the difference between AS and KS because their prognosis and treatment are very different. Identification by immunohistochemistry of HHV‐8 is useful for the distinction between KS and AS or BLAP.  相似文献   
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The use of endogenous Protoporphyrin IX generated through the heme biosynthetic pathway after administration of 5-aminolevulinic acid (ALA) has led to many applications in photodynamic therapy (PDT). In Buenos Aires, Argentina, the Centro de Investigaciones sobre Porfirinas y Porfirias (CIPYP), reported for the first time, in 1975, porphyrin synthesis from ALA in highly dividing plant tissues. Increased porphyrin synthesis in tumours as well as cell photosensitisation was reported soon after. Our group is also interested in studying the use of new synthetic lipophilic derivatives of ALA as well as ALA delivery in liposomes. We have elucidated the mechanism of ALA transport in mammalian and yeast cells. The interactions between ALA-PDT and nitric oxide were investigated in three murine adenocarcinoma cell lines. In the National University of Río Cuarto, Córdoba, a group is devoted to the synthesis of new porphyrin-derived photosensitisers to study their effects on photoinactivation of bacterial and mammalian cells death by PDT. At the Centre of Electron Microscopy of the Cordoba National University, a prototype of a 630 nm noncoherent light source was designed and constructed. Cost of the light source and scarce knowledge of the benefits of PDT by physicians limit the spread of the treatment throughout the country.  相似文献   
8.
Paul Lombardo   《Radiography》2006,12(4):332-338
The Australian higher education system is in a state of great change. The Federal education minister, Dr Brendan Nelson, has indicated that he intends to continue introducing far-reaching reforms that will impact significantly on how universities conduct teaching and research. The future allocation of government funding for university programs, including those in medical radiation, will have a significant effect on how those programs are delivered and could even determine whether programs remain viable. There will be a financial imperative for academic departments to strengthen research activity and to obtain funding from non-government sources, such as full-fee paying students, in order to generate enough income to cover program delivery. Medical radiation education in Australia is also facing many other challenges. Some of these are longstanding, such as the high cost of medical radiation program delivery, poor levels of research activity and difficulty in recruiting and retaining academic staff. Other problems have arisen recently, such as increased competition for students and a critical shortage of available training placements in clinical practice. The aim of this paper is to raise and explore these issues from a university perspective.  相似文献   
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Abstract: The current study examined the extent to which mothers, fathers, teachers, and teenage friends influenced Latino adolescents’ academic motivation. Using path analysis, separate models were tested for 154 Latino boys and 156 Latina girls. Findings indicated that mothers’ and teachers’ academic support were positively related to adolescent girls’ academic motivation, and fathers’ and teachers’ academic support were positively related to adolescent boys’ academic motivation. The salience of teachers’ support, possible reasons for gender differences, and implications for future research are discussed.  相似文献   
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We report a case of a prepubertal girl with juvenile primary hypothyroidism presenting as ovarian cysts and precocious puberty. The 7-year-old female was referred to our clinic because of a pelvic/abdominal mass and vaginal bleeding. Besides these findings, on physical examination we noticed the thyroid gland globally increased and the presence of secondary sexual characteristics. Based upon the clinical profile and investigations, the patient was diagnosed with juvenile primary hypothyroidism due to autoimmune thyroiditis. The cysts and precocious puberty resolved spontaneously after the simple replacement of thyroid hormone. It is important to bear in mind hypothyroidism in cases of girls presenting ovarian cysts and precocious puberty in order to avoid unnecessary surgery on the ovaries.  相似文献   
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