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排序方式: 共有1457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.
Erin C. Tully Jackson M. Gray Sherryl H. Goodman Stephen Nowicki Jr. 《Early child development and care》2016,186(12):1939-1951
Children who expect they can bring about good outcomes and avoid bad outcomes tend to experience more personal successes. Little is known about factors that contribute to these ‘control expectancies’. The purpose of the present study was to determine whether children's internal control expectancies occur in the context of parents’ internal control expectancies, low family strain, and high family cohesiveness and whether these factors are more strongly related to daughters’ than sons’ control expectancies. A community sample of 85 children aged 9–11 years and their parents (85 mothers; 63 fathers) completed rating scales. Fathers’ more internal control expectancies and mothers’ reports of fewer family strains were associated with daughters’ but not sons’ greater internal control expectancies, and greater family cohesiveness was related to both daughters’ and sons’ internal control orientations. These findings suggest that family factors may contribute to children's, particularly daughters’, development of internal control expectancies. 相似文献
3.
J Grogan B H Nowicki T A Schmidt V M Haughton 《AJNR. American journal of neuroradiology》1997,18(7):1325
PURPOSETo study the relationship of lumbar facet joint tropism to degeneration of the cartilage and subcortical bone in the facet joints and the effect of tropism in intervertebral disk degeneration.METHODSThe orientation of 104 cadaveric lumbar facet joints with respect to sagittal plane was measured on CT scans, and the joints were classified as having no tropism, mild tropism, or severe tropism. On MR images, the severity of cartilage degeneration and bony sclerosis was measured. The correlation between tropism and degeneration was calculated, as was the relationship among age, spinal level, and degeneration.RESULTSWe identified four spinal levels with severe tropism, six with moderate tropism, and 94 without tropism. Cartilage degeneration was not significantly more severe in the joints with tropism than in the joints without. Sclerosis was slightly greater in the joints with tropism than in the joints without it. Sclerosis and cartilage degeneration were significantly related to age and spinal level.CONCLUSIONAge, spinal level, and overall facet joint angle are more important factors in facet joint degeneration than is tropism. 相似文献
4.
There is evidence that leukocyte contaminating red blood cells and platelet concentrates are responsible for refractoriness to platelet transfusions. The efficacy of a cotton-wool filter to remove leukocytes from red blood cells has been documented previously. The present study was designed to evaluate whether the cotton-wool filters can effectively remove leukocytes from platelet concentrates. Sixty pools of random-donor platelets and single-donor plateletpheresis products were filtered through a cotton-wool filter. The efficacy of filtration was determined by measuring the absolute numbers of leukocytes and platelets and subpopulations of mononuclear cells. The average platelet loss was 8% per pool of random platelets and 10% per plateletpheresis product. The average leukocyte removal was 99% from a pool of random platelets and plateletpheresis concentrates collected by CS-3000 and 90% from plateletpheresis concentrates harvested by single-stage COBE/IBM-2997. The filtration removed 100% of granulocytes, 95% of monocytes, 90% of B-lymphocytes, and 85% of T-lymphocytes. We conclude that filtration through a cotton-wool filter is an efficient and cost-effective method for preparation of leukocyte-poor platelets. 相似文献
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7.
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
8.
Interaction of Dr adhesin with collagen type IV is a critical step in Escherichia coli renal persistence 下载免费PDF全文
Selvarangan R Goluszko P Singhal J Carnoy C Moseley S Hudson B Nowicki S Nowicki B 《Infection and immunity》2004,72(8):4827-4835
The pathogenic mechanism of recurrent or chronic urinary tract infection is poorly understood. Escherichia coli cells bearing Dr fimbriae display unique tropism to the basement membrane (BM)-renal interstitium that enables the bacteria to cause chronic pyelonephritis in experimental mice. The renal receptors for Dr-fimbriated E. coli are type IV collagen and decay-accelerating factor (DAF). We hypothesized that type IV collagen receptor-mediated BM-interstitial tropism is essential for E. coli to cause chronic pyelonephritis. To test the role of the type IV collagen tropism of Dr-fimbriated E. coli in renal persistence, we constructed an isogenic mutant in the DraE adhesin subunit that was unable to bind type IV collagen but retained binding to DAF and examined its virulence in the mouse model. The collagen-binding mutant DrI113T was eliminated from the mouse renal tissues in 6 to 8 weeks, while the parent strain caused persistent renal infection that lasted at least 14 weeks (P < or = 0.02). Transcomplementation with the intact Dr operon restored collagen-binding activity, BM-interstitial tropism, and the ability to cause persistent renal infection. We conclude that type IV collagen binding mediated by DraE adhesin is a critical step for the development of persistent renal infection in a murine model of E. coli pyelonephritis. 相似文献
9.
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
10.
Dra/AfaE adhesin of uropathogenic Dr/Afa+ Escherichia coli mediates mortality in pregnant rats 总被引:1,自引:0,他引:1 下载免费PDF全文
Wroblewska-Seniuk K Selvarangan R Hart A Pladzyk R Goluszko P Jafari A du Merle L Nowicki S Yallampalli C Le Bouguénec C Nowicki B 《Infection and immunity》2005,73(11):7597-7601
Escherichia coli bearing adhesins of the Dr/Afa family frequently causes urogenital infections during pregnancy in humans and has been associated with mortality in pregnant rats. Two components of the adhesin, Dra/AfaE and Dra/AfaD, considered virulence factors, are responsible for bacterial binding and internalization. We hypothesize that gestational mortality caused by Dr/Afa+ E. coli is mediated by one of these two proteins, Dra/AfaE or Dra/AfaD. In this study, using afaE and/or afaD mutants, we investigated the role of the afaE and afaD genes in the mortality of pregnant rats from intrauterine infection. Sprague-Dawley rats, on the 17th day of pregnancy, were infected with the E. coli afaE+ afaD and afaE afaD+ mutants. The clinical E. coli strain (afaE+ afaD+) and the afaE afaD double mutant were used as positive and negative controls, respectively. The mortality rate was evaluated 24 h after infection. The highest maternal mortality was observed in the group infected with the afaE+ afaD+ strain, followed by the group infected with the afaE+ afaD strain. The mortality was dose dependent. The afaE afaD double mutant did not cause maternal mortality, even with the highest infection dose. The in vivo studies corresponded with the invasion assay, where the afaE+ strains were the most invasive (afaE+ afaD strain > afaE+ afaD+ strain), while the afaE mutant strains (afaE afaD+ and afaE afaD strains) seemed to be noninvasive. This study shows for the first time that the afaE gene coding for the AfaE subunit of Dr/Afa adhesin is involved in the lethal outcome of gestational infection in rats. This lethal effect associated with AfaE correlates with the invasiveness of afaE+ E. coli strains in vitro. 相似文献