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排序方式: 共有1297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.
Kamil Torres Anna Torres Grzegorz J. Staśkiewicz Andrzej Chrościcki Tadeusz Łoś Ryszard Maciejewski 《Surgical endoscopy》2009,23(9):2117-2123
Background Surgical procedures enhance production of pro- and anti-inflammatory cytokines and angiogenic factors that play a pivotal
role in the immunological response to surgical trauma and take part in the pathogenesis of tumor growth and adhesions formation.
The purpose of the study was to access the influence of low-pressure CO2 pneumoperitoneum on the inflammatory and angiogenic responses during the postoperative period after laparoscopy.
Methods The study group consisted of 40 patients, operated on due to cholelithiasis using standard-pressure (n = 20) and low-pressure (n = 20) CO2 pneumoperitoneum. Serum concentration of interleukin (IL)-6, IL-8, IL-10, vascular endothelial growth factor (VEGF)-A, and
endostatin were measured before and at 6, 24, and 48 h after surgery with commercially available enzyme-linked immunosorbent
assay (ELISA).
Results Concentrations of IL-6 increased significantly after the operations in both groups. No differences were observed between the
groups in regards to IL-6, IL-8, and IL-10 levels. Concentrations of VEGF-A measured at 6 and 48 h were significantly lower
in patients who underwent laparoscopies performed with low-pressure pneumoperitoneum. No significant variations were observed
in endostatin serum concentration. Concentrations of the studied parameters were not influenced by duration of surgery or
by age, gender, or body mass index (BMI) of the patients.
Conclusions The results obtained in our study do not show any significant differences between studied operative procedures with regards
to systemic inflammatory response. Changes in the concentrations of VEGF-A and endostatin observed in the studied population
may suggest this technique is more favorable with regards to angiogenesis process intensity, along with all its consequences
and implications. 相似文献
3.
Ryszard Szymanski Nevena Manolova Ilia Rashkov 《Macromolecular chemistry and physics.》1993,194(3):941-951
The mechanism of the activated-monomer polymerization of ethylene oxide catalyzed by protic acids was investigated by means of an analysis of the molecular-weight distribution curves from the polymers obtained. The results suggest that polymer ether groups participate in the polymerization by forming hydrogen-bonded complexes and tertiary oxonium cations in the reaction with the activated monomer, both being intermediates of the propagation reactions. 相似文献
4.
Zielonka TM Marchel A Pogorzelski R Górska K Safianowska A Byśkiniewicz K Chazan R 《Pneumonologia i alergologia polska》2004,72(9-10):429-432
The authors describe the case of survival for the period of 10 years after brain metastasis surgery and removal of the left lung upper lobe due to adeno-squamous cells carcinoma. Surgery did not generate any complications. Within 8 years after the surgery the radiological examination showed infiltrations resembling changes typical for tuberculosis. Microbiological analysis showed a culture of Mycobacterium kansasi leading to diagnosis of mycobacteriosis. Hence the antituberculous treatment was extended to 12 months to be interrupted due to liver damage. Two years later the patient experienced incident of haemoptysis. Detailed examination and assessment of the respiratory tract condition revealed COPD without features of renewal of the neoplastic process or infection by Mycobacterium tuberculosis or mycobacterium other than tuberculosis. This case demonstrates that aggressive surgical approaches to lung cancer with solitary cerebral metastasis significantly improve patient survival and justifies its widespread use. 相似文献
5.
Franciszek Burdan Zofia Siezieniewska Ryszard Maciejewski Barbara Madej Elzbieta Radzikowska Zbigniew Wojtowicz 《Experimental and toxicologic pathology》2002,53(6):453-459
The aim of the study was to establish the influence of short-time omeprazole administration on liver function and morphology. Omeprazole was administered intraperitoneally, twice daily, for 3 days to male Wistar rats in two doses: 0.571 mg/kg and 5.71 mg/kg. Control animals were treated with physiological saline. Half of the animals were sacrificed 12 hours after the last injection. The remaining rats were raised for another 6 weeks, without any xenobiotics, and sacrificed on the 47th day of the experiment. The activity of free and bound fractions of hepatic acid phosphatase, beta-galactosidase, beta-N-acetyl-glucosaminidase, cathepsin B, D and L, lipase, and sulphatase were determined spectrophotometrically in homogenates of the liver. The liver sections were examined by light microscopy with hematoxylin-eosin, azan, and periodic acid-Schiff stains. Marginally significant (p < 0.1) differences in activity of free sulphatase fraction, and free and bound fractions of beta-galactosidase were found in animals exposed to the higher dose of omeprazole and sacrificed 12 hours after the last injection. Enzymatic profiles were normalised during the next 6 weeks. Histological evaluation revealed small degenerative and adaptive changes in all examined groups. It could be concluded that observed differences of hepatic lysosomal enzyme activities were the result of accompanied chemical-induced peritonitis as previously reported, and not a direct drug-toxic effect. 相似文献
6.
The purpose of this study was to see whether menarcheal age assessment by means of the most frequently used methods that were conducted every time on the same group of girls would yield the same results. One hundred and one Polish girls, whose ages at menarche were recorded in a longitudinal study between 1976 and 1990, were asked to recall the age of menarche in 2004. The mean menarcheal ages of those women were calculated by means of the probit (PA), prospective (AA), retrospective method without age correction (RA), and retrospective method with the recall age corrected by 0.5 year (RcA). The PA, AA, and retrospective methods: RA and RcA revealed results: 13.14 +/- 1.1; 13.10 +/- 1.1; 13.12 +/- 1.36, and 14.39 +/- 1.34 years, respectively. The menarcheal AA was insignificantly different from the PA (95% CI) and RA. The RcA was significantly higher than the AA and RA (P = 0.05). The correlation coefficient (r) between AA and RA was 0.70. Only 16% of the interviewed women accurately remembered the date of their menarche, 63% of them missed their menarche time by about 1 year, whereas 22% were wrong by 2 and more years. (1) The PA and the AA method yield comparable results when estimating menarcheal age. (2) The menarcheal age determined by the retrospective methods is not very reliable and the application of age correction overestimates the results. 相似文献
7.
Rutkowski R Moniuszko T Stasiak-Barmuta A Kosztyła-Hojna B Alifier M Rutkowski K Tatarczuk-Krawiel A 《Archivum immunologiae et therapiae experimentalis》2003,51(6):421-428
CD80 and CD86 seem to play an important role in the allergen-induced secretion of interleukin (IL)-5 and IL-13. Up to now, the expressions of CD80 (B7.1) and CD86 (B7.2) on monocytes and the kinetics of the expression of these molecules on lipopolysaccharide-stimulated monocytes in nonatopic asthma have not been defined. Using monoclonal antibodies, we have compared the expressions of CD80 (B7.1) and CD86 (B7.2) on the monocytes of healthy persons and nonatopic asthmatic patients. We have also assessed the effect of CD80 and CD86 inactivation on IL-4 and interferon (IFN)-gamma production in nonatopic asthmatics and healthy subjects. We found that a low expression of CD80 (1.64 +/- 0.65 vs. 3.53 +/- 1.43%) and a moderate expression of CD86 (41.25 +/- 13.4 vs. 49.46 +/- 11.49%) on the studied monocytes were characteristic for asthma. In nonatopic asthma patients inactivation of CD80 or CD86 blockade significantly reduced IFN-gamma production by T lymphocytes (p < 0.02; p < 0.03). In both the studied groups, anti-CD80 antibodies did not diminish T lymphocyte production of IL-4. However, anti-CD86 antibodies significantly (p < 0.04) reduced the IL-4 concentration in culture supernatants. Our results confirm that both the CD80 and CD86 molecules play an important role in the maintenance and amplification of the inflammatory process. It suggests that in the inflammatory process that occurs in nonatopic bronchial asthma, Th1 as well as Th2 lymphocytes are equally important. 相似文献
8.
Ryszard Grucza Yoshimi Miyamoto Yoshimi Nakazono 《European journal of applied physiology》1990,61(3-4):230-236
Summary Kinetics of cardiorespiratory response to dynamic (DE) and then to rhythmic-static exercise (RSE) was compared in nine male subjects exercising in an upright position on a cycle ergometer at an intensity of about 50 %
O2max and a mean pedalling frequency of 60 rpm over 5 min. Respiratory frequency (f
R), tidal volume (V
T), minute ventilation (
E), heart rate (f
c), stroke volume (SV), and cardiac output (Q
t) were measured continuously. The RSE caused a greater increase in f
R than DE, whereas V
T increased more during DE. The effect of reciprocal changes in f
R and V
T was that
E and its kinetics, expressed as a time constant (), did not differ between experimental situations. The ventilatory equivalent for O2 (
E:
O2) was greater for RSE (31.3) than for DE (23.0, P<0.01). Elevation of f
c was similar for both types of exercise. The SV increased suddenly at the beginning of DE from 54 ml to 74 ml and then decreased to the end of exercise. At the onset of RSE only a moderate increase in SV was observed, from 56 ml to 62 ml, and then SV remained stable. The DE caused a greater and faster increase in Q
t (4.20 l · min–1, for equal to 16.1s) than RSE (3.25 l · min–1, for equal to 57.0s, P<0.05 and P<0.002, respectively). Total peripheral resistance was almost 40% greater for RSE than for DE. No relationship was found between Q
t and VE at the first 15 s of both types of exercise. It is concluded that the kinetics of
E did not depend on to kinetics of Q
t in the exercising subjects. This finding contradicts the hypothesis of cardiodynamic hyperpnoea indicating an importance of neurogenic factors, mediated either centrally or peripherally, in fast cardiorespiratory responses to exercise. 相似文献
9.
Korona R 《Research in microbiology》2004,155(5):301-310
Yeast has proven to be a very useful model organism for studying eukaryotic cell functions. Its applicability for population and quantitative genetics is less well known. Among its advantages is the ease of screening for mutants. The present paper reviews experiments aimed at estimating the parameters of spontaneous mutations deleterious to fitness. The rate of deleterious mutation was found to be moderately high. A large fraction of detectable mutants were lethal; among the non-lethal mutants, the least harmful ones dominated. Deleterious mutations, and especially the lethal ones, were generally very well masked by wild-type alleles when in heterozygous loci. The negative effects of mutations were much stronger under stressful than under benign conditions. Interactions between loci with deleterious mutations did alter their fitness, but no strong overall effect of synergism or antagonisms was observed. 相似文献
10.
A HeLa cell line stably expressing the enhanced green fluorescence protein (EGFP) gene, interrupted by the HBB IVS2‐654 intron, was studied without treatment and after treatment with a single standard dose of 15 μM of N‐methyl‐N′‐nitro‐N‐nitrosoguanidine (MNNG). This assay was done in order to prove that such a construct can revert by a variety of mechanisms and that it produces a visible phenotype, i.e., green fluorescence. The system permits visual detection of living mutant cells among a background of non‐mutant cells and does not require a selective medium. The results show that the construct reverts by large deletions (–62, –100, and –162 bp), small insertions (+4 bp), small rearrangements (19 bp duplication), base substitutions at purines (G652, G653, A655, G579), and a pyrimidine (T654) between nucleotide positions 579 and 837. Splice‐site mutations were recovered, and some of the mechanisms underlying these mutations are discussed. Because of the ease of detection of revertant cells under fluorescent light and the wide variety of mutations that can be recovered, further development of this system could make it a useful new mammalian cell mutagenicity assay. Hum Mutat 18:526–534, 2001. © 2001 Wiley‐Liss, Inc. 相似文献