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排序方式: 共有956条查询结果,搜索用时 15 毫秒
1.
Jakub Pazdrowski Aleksandra Daczak‐Pazdrowska Adriana Polaska Joanna Ka
mierska Wojciech Barczak Mateusz Szewczyk Pawe Golusiski Zygmunt Adamski Ryszard aba Wojciech Golusiski 《Skin research and technology》2019,25(6):857-861
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
2.
A blocking ELISA (B/ELISA) for detecting antibodies to bovine ephemeral fever virus (BEFV) in cattle is described. In this test, the binding capacity of a monoclonal antibody specific for an epitope on antigenic site G1 of the BEF virus glycoprotein is blocked in the presence of positive serum. The sensitivity of the B/ELISA was compared with the virus neutralisation (VN) test using a total of 380 sera from cattle. Of these, 118 were from an area known to be free of bovine ephemeral fever, 181 from naturally and experimentally BEFV-infected cattle, 33 sequential serum samples from a sentinel steer from which Berrimah virus (BERV) had been isolated, 9 from a sentinel cow from which Kimberley virus (KIMV) was isolated and a panel of 39 sera supplied as a blind trial. The B/ELISA results overall compared favourably with those of the VN tests. The monospecificity of the test was demonstrated using hyperimmune mouse ascitic fluid to other BEF serogroup viruses, namely KIM and BER viruses and the results showed no significant cross-reaction. The greater simplicity and sensitivity of the test when compared with the VN test makes it the preferred test for the diagnosis and monitoring of clinical bovine ephemeral fever. 相似文献
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Dietrich Schweitzer Sabine Guenther Mateusz Scibor Martin Hammer 《International ophthalmology》1992,16(4-5):251-257
The approximation of logarithmic difference spectra between the reflectance of the normal fundus and the fundus reflectance in different stages of glaucoma is demonstrated by a model. The influences of fundus pigments like oxihemoglobin, melanin, xanthophyll and rhodopsin as well as the intensity and the exponent of the scattered light are optimized. Glaucomatous alterations in the extinction of these pigments and of the scattering parameters are different in the macula, in the papillo-macular bundle and in the parapapillary region temporal to the optic disc. A lack of oxihemoglobin only in the papillo-macular bundle in first relative losses in the visual field function points to a damaged microcirculation in early POAG. In progressive glaucoma the extinction spectrum of xanthophyll is detectable in the papillo-macular bundle. A decreased intensity of the scattered light and an altered scattering exponent are suggestive of a damage in the nerve fiber layer at early stages of glaucoma. 相似文献
5.
Achkar JM Burda ST Konings FA Urbanski MM Williams CA Seifen D Kahirimbanyi MN Vogler M Parta M Lupatkin HC Zolla-Pazner S Nyambi PN 《Journal of acquired immune deficiency syndromes (1999)》2004,36(3):835-844
OBJECTIVE: To document infection with HIV type 1 (HIV-1) group M non-B subtypes in individuals living in New York City. DESIGN: From October 1999 through April 2003, HIV-1-seropositive individuals were selected from 3 clinics in New York City based on having risk factors for infection with HIV-1 non-B subtypes. METHODS: HIV-1 RNA was extracted from plasma samples, and partial gag, pol, or env genes were amplified by PCR analysis. The infecting HIV-1 group M subtype was determined based on results of either heteroduplex mobility assay or sequencing and phylogenetic analysis. RESULTS: Ninety-seven subjects were enrolled in the study. Of the 97 subjects, 91 (94%) were selected based on having emigrated from a non-European country, while 6 (6%) were native United States citizens. Subtypes were successfully determined in 53 (55%) of the 97 plasma samples tested. The subtypes in 2 plasma samples were unclassifiable. HIV-1 infections were classified as those due to the following group M subtypes: A (n = 4; 7%), B (n = 12; 22%), C (n = 8; 15%), F (n = 2; 4%), CRF01_AE-like (n = 7; 13%), CRF02_AG-like (n = 19; 34%), an intersubtype recombinant form G/A (n = 1; 2%), and unclassifiable viruses (n = 2; 4%). CONCLUSION: This study reveals infection with a broad variety of HIV-1 group M subtypes mostly in the immigrant population of New York City as well as how several non-B subtypes are being introduced into the United States. 相似文献
6.
Zakrzewski K Kubicki M Polis L Nowosławska E Liberski PP 《Folia neuropathologica / Association of Polish Neuropathologists and Medical Research Centre, Polish Academy of Sciences》1999,37(3):148-151
Forty-five children with primary brain tumors were evaluated by in vivo proton magnetic resonance spectroscopy (MRS) with the aim of detecting correlations between the obtained spectra and tumor malignancy and histology. All investigations were performed using a 1.5 T MR scanner (Picker) with point-resolved spectroscopic (PRESS) sequence (TR 1600 ms, TE 270 ms, NEX 256). Spectra were analyzed for N-acetylaspartate (NAA), choline containing-compounds (Cho), creatine and phosphocreatine (Cr) and lactate (Lac). The Cho/NAA ratio was the most useful parameter for differentiating between normal brain, benign and malignant tumors as well as discriminating the three main groups of pediatric brain tumors namely pilocytic astrocytoma, ependymoma and medulloblastoma. Proton MRS appears to be an important noninvasive technique in the differential diagnosis of pediatric brain tumors. 相似文献
7.
Fiks T Jesionek-Kupnicka D Zakrzewski K Polis L Liberski PP 《Folia neuropathologica / Association of Polish Neuropathologists and Medical Research Centre, Polish Academy of Sciences》1999,37(3):152-156
We present here a clinico-pathological analysis of 58 pilocytic astrocytomas (PA) and 11 gangliogliomas (GG) based on an analysis of neuronal markers (GFAP, SYN, NFP) in these two groups of neoplasms. During the retrospective review of 58 cases recognized primarily as PA, 11 verified neoplasms demonstrated strong reaction for SYN or NFP or for both antibodies. These cases were reclassified as gangliogliomas. None of 11 tumors recognized as GG were further reclassified as PA. The overall 5-year survival was 88.89% in PA and 70.00% in GG group. 相似文献
8.
Katarzyna Winiarska Jolanta M. Dzik Mateusz Labudda Dorota Focht Bartosz Sierakowski Aleksandra Owczarek Lukasz Komorowski Wojciech Bielecki 《Journal of pineal research》2016,60(1):109-117
Excessive activity of NADPH oxidase (Nox) is considered to be of importance for the progress of diabetic nephropathy. The aim of the study was to elucidate the effect of melatonin, known for its nephroprotective properties, on Nox activity under diabetic conditions. The experiments were performed on three groups of animals: (i) untreated lean (?/+) Zucker diabetic fatty (ZDF) rats; (ii) untreated obese diabetic (fa/fa) ZDF rats; and (iii) ZDF fa/fa rats treated with melatonin (20 mg/L) in drinking water. Urinary albumin excretion was measured weekly. After 4 wk of the treatment, the following parameters were determined in kidney cortex: Nox activity, expression of subunits of the enzyme, their phosphorylation and subcellular distribution. Histological studies were also performed. Compared to ?/+ controls, ZDF fa/fa rats exhibited increased renal Nox activity, augmented expression of Nox4 and p47phox subunits, elevated level of p47phox phosphorylation, and enlarged phospho‐p47phox and p67phox content in membrane. Melatonin administration to ZDF fa/fa rats resulted in the improvement of renal functions, as manifested by considerable attenuation of albuminuria and some amelioration of structural abnormalities. The treatment turned out to nearly normalize Nox activity, which was accompanied by considerably lowered expression and diminished membrane distribution of regulatory subunits, that is, phospho‐p47phox and p67phox. Thus, it is concluded that: (i) melatonin beneficial action against diabetic nephropathy involves attenuation of the excessive activity of Nox; and (ii) the mechanism of melatonin inhibitory effect on Nox is based on the mitigation of expression and membrane translocation of its regulatory subunits. 相似文献
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