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排序方式: 共有659条查询结果,搜索用时 15 毫秒
651.
Prof. Dr. Helga Kirchhoff Ute Boldt Renate Rosengarten Anette Klein-Struckmeier 《Current microbiology》1987,15(1):57-60
Mycoplasma sp. nov. strain 163K, the gliding microorganism isolated from the gills of a tench (Tinca tinca L.), is capable of chemotaxis, being attracted to sugars, amino acids, and mucus. The chemotactic behavior of the organisms was microscopically investigated and documented by long-time exposure photomicrographs providing motility tracks. In diffusion-generated concentration gradients of chemoattractive substances, the random motion of the mycoplasmas was strongly biased in the direction of increasing attractant concentrations. 相似文献
652.
Dr. Wolfgang Hösel Anette Fiedler-Preiss Edith Borgmann 《Plant Cell, Tissue and Organ Culture》1981,1(1):137-148
A combination of the phytohormones naphthalene acetic acid and benzylaminopurine (5 μM each) allows lignification in various plant cell cultures. This system has been used to investigate the relationship between
the coniferin-hydrolyzingβ-glucosidase activity and lignification. InPetroselinum hortense andTriticum aestipum cell cultures the appearance of this enzymatic activity coincided with lignification. In parsley cell cultures it was moreover
shown that this activity appears concomitantly with other lignin biosynthetic enzymes. The unique enzymes of the flavonoid
pathway did not appear by this phytohormone treatment. In other cell cultures investigated the correlation between the coniferin-hydrolyzing
activity and lignification was not as evident as in the above two cases. This was probably due to the high activity of coniferin
glucosidase already present in the normally grown cultures. Coniferinβ-glucosidase was found in all lignified cell cultures. 相似文献
653.
Halvor Naess Solveig Glad Anette Storstein Christine H Rinaldo Sverre J Mørk Kjell-Morten Myhr Hans Hirsch 《BMC neurology》2010,10(1):32
Background
To report the clinical course of PML in an apparently immunocompetent patient treated with cidofovir. 相似文献654.
655.
Sissel Evy Monstad Anette Knudsen Helga B. Salvesen Jan H. Aarseth Christian A. Vedeler 《Cancer immunology, immunotherapy : CII》2009,58(11):1795-1800
Purpose We assessed the frequency and levels of onconeural antibodies in 974 patients with various types of tumours, but without apparent
paraneoplastic neurological syndromes (PNS).
Patients and methods We included patients with the following tumours: 200 small-cell lung cancer (SCLC) patients, 253 breast cancer patients, 182
ovarian cancer patients, 266 uterine cancer patients and 73 thymoma patients, as well as 52 patients with PNS and cancer and
300 healthy blood donors. Sera were screened for amphiphysin, CRMP5, Hu, Ma2, Ri and Yo antibodies using a multi-well immunoprecipitation
technique.
Results The most frequently detected antibodies were Hu followed by CRMP5. Ma2, Yo, amphiphysin and Ri antibodies were less common,
but each was found at similar frequencies. Onconeural antibodies were present at similar levels in sera from the PNS control
group and from cancer patients. Hu antibodies were rare in cancers other than SCLC. CRMP5 was the only antibody found in patients
with thymoma and this antibody was more common among patients with thymoma than in other tumour patients. With one exception,
coexisting antibodies were only found in patients with SCLC. The presence of onconeural antibodies in SCLC patients was not
associated with prolonged survival.
Conclusion Onconeural antibodies are associated with various types of tumours suggesting that all antibodies should be included in the
serological screening for possible PNS. The levels of onconeural antibody are not sufficiently sensitive to discriminate between
cancer patients with PNS and those without. 相似文献
656.
Katrine Pilely Solveig B. Nielsen Anette Draborg Maiken L. Henriksen Søren W. K. Hansen Lars Skriver Ejvind Mørtz Rikke R. Lund 《Biotechnology progress》2020,36(4):e2983
Monitoring host cell proteins (HCPs) is one of the most important analytical requirements in production of recombinant biopharmaceuticals to ensure product purity and patient safety. Enzyme-linked immunosorbent assay (ELISA) is the standard method for monitoring HCP clearance. It is important to validate that the critical reagent of an ELISA, the HCP antibody, covers a broad spectrum of the HCPs potentially present in the purified drug substance. Current coverage methods for assessing HCP antibody coverage are based on 2D-Western blot or immunoaffinity-purification combined with 2D gel electrophoresis and have several limitations. In the present study, we present a novel coverage method combining ELISA-based immunocapture with protein identification by liquid chromatography–tandem mass spectrometry (LC–MS/MS): ELISA-MS. ELISA-MS is used to accurately determine HCP coverage of an early process sample by three commercially available anti-Escherichia coli HCP antibodies, evading the limitations of current methods for coverage analysis, and taking advantage of the benefits of MS analysis. The results obtained comprise a list of individual HCPs covered by each HCP antibody. The novel method shows high sensitivity, high reproducibility, and enables tight control of nonspecific binding through inclusion of a species-specific isotype control antibody. We propose that ELISA-MS will be a valuable supplement to existing coverage methods or even a replacement. ELISA-MS will increase the possibility of selecting the best HCP ELISA, thus improving HCP surveillance and resulting in a final HCP profile with the lowest achievable risk. Overall, this will be beneficial to both the pharmaceutical industry and patient safety. 相似文献
657.
658.
Sarah Roßbach Tanja Diederichs Ute Nöthlings Anette E Buyken 《Chronobiology international》2018,35(3):336-347
During adolescence, a shift from morningness to eveningness occurs, yet school continues to start early in the morning. Hence, adolescents are at risk for social jetlag, i.e. a discrepancy between biological and social timing. It remains to be determined whether chronotype associates with daily and daytime-specific eating patterns during this potentially critical period. Therefore, the aim of the present study was to investigate whether chronotype is decisive for daily eating patterns [total energy intake (TEI, kcal), total macronutrient intake (% of TEI), eating occasion frequency (n/day), meal frequency (n/day), snack frequency (n/day), duration of nightly fasting], or daytime-specific eating patterns [morning (before 11 am) energy intake (% of TEI), morning macronutrient intake (% of morning energy intake), regular breakfast skipping (no morning energy intake at least on 2 of 3?days, yes/no), evening (after 6 pm) energy intake (% of TEI), evening macronutrient intake (% of evening energy intake), regular dinner skipping (no evening energy intake at least on 2 of 3?days, yes/no)] in German adolescents. Chronotype was assessed by use of the Munich Chronotype Questionnaire and is defined as the midpoint of sleep corrected for sleep-debt accumulated over the workweek (the later the midpoint of sleep, the later the chronotype). A total of 223 participants (10–18?years) provided 346 questionnaires and concurrent 3-day weighed dietary records. Associations between chronotype and eating patterns were analyzed cross-sectionally using multivariable linear and logistic mixed-effects regression models. Adolescents with earlier and later chronotypes did not differ in their daily eating patterns. With respect to daytime-specific eating patterns, 1?h delay in chronotype was associated with 4.0 (95% CI 2.5–6.6) greater odds of regular breakfast skipping (p < 0.0001). In addition, later chronotype was associated with higher evening energy intake (p = 0.0009). In conclusion, our data show that a later chronotype among adolescents is associated with a shift of food consumption toward later times of the day. Hence, adolescents’ eating patterns appear to follow their internal clock rather than socially determined schedules. 相似文献
659.