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排序方式: 共有548条查询结果,搜索用时 15 毫秒
71.
72.
Marius G. Lambrechts Isak S. Pretorius Julius Marmur Paul Sollitti 《Yeast (Chichester, England)》1995,11(8):783-787
The polymorphic extracellular glucoamylase-encoding genes STA1 (chr. IV), STA2 (chr. II) and STA3 (chr. XIV), from Saccharomyces cerevisiae var. diastaticus probably evolved by genomic rearrangement of DNA regions (S1, S2 and SGA1) present in S. cerevisiae, and subsequent translocation to unlinked regions of chromosomal regions. S1, encoding a homologue to the threonine/serine-rich domain of STA glucoamylases (GAI-III), mapped to the right arm of chromosome IX. S2, encoding the hydrophobic leader peptide of GAI-III, was also mapped on the right arm of chromosome IX, next to S1, close to DAL81. The SGA1 sporulation-specific, intracellular glucoamylase-encoding gene is located on the left arm of chromosome IX, 32 kb proximal of HIS5. 相似文献
73.
H Tavaf-Motamen DN Ader MW Browne CD Shriver 《Canadian Metallurgical Quarterly》1998,133(2):211-3; discussion 214
OBJECTIVE: To describe an accurate and reproducible method to quantify a patient's subjective experience of breast pain. DESIGN: Prospective diary study. SETTING: Military tertiary care hospital. PATIENTS: Thirty female military health care beneficiaries from the Walter Reed Army Medical Center, Washington, DC, gynecology and general surgery clinics. MAIN OUTCOME MEASURES: Daily mastalgia was recorded using a visual analog scale and menstrual symptoms were measured using a daily questionnaire. These measures were correlated with results of a screening questionnaire completed prior to study entry. RESULTS: Patients identified as having cyclical mastalgia based on the screening questionnaire (n= 15) were found to have higher peak perimenstrual mastalgia according to their daily diaries than patients who did not meet diagnostic criteria (n=15) (5.3+/-0.7 vs 3.5+/-0.5, P<.001). Applying the same criteria used in the screening questionnaire to the diary data, 17 of 30 patients met diagnostic criteria for cyclical mastalgia. The ability of the screening questionnaire to predict the results of the prospective diary data was calculated, and positive and negative predictive values were 73% and 60%, respectively. Most patients with cyclical mastalgia also have other perimenstrual psychological and somatic complaints, although a subset of patients has high levels of mastalgia with minimal associated symptoms. CONCLUSIONS: Accurate assessment of mastalgia cannot be done with a retrospective questionnaire and requires prospective diary evaluation, owing to the variable and subjective nature of symptoms and recall bias. A daily visual analog scale provides reproducible results and is easy for patients to use. 相似文献
74.
Manschreck Theo C.; Maher Brendan A.; Rucklos Mary E.; Veneer Donald R. Jr.; Ader Deborah N. 《Canadian Metallurgical Quarterly》1981,90(4):321
Introduced a laboratory measure of motor function, synchronization of tapping with an auditory stimulus, as an index of motor disorganization in schizophrenia. It was hypothesized that (a) schizophrenics' performance on this task would be distinguishable from that of controls and would reflect a relative inability to take advantage of stimulus predictability, independent of task difficulty; (b) clinical measures of disturbed motor behavior would be associated with poorer synchronization; and (c) synchronization performance would be associated with clinical ratings of formal thought disorder and type-token ratio assessment of disorganization in spoken language. 16 schizophrenic, 8 affective, and 8 normal controls (18–48 yrs) were studied. The schizophrenics showed a specific pattern of disrupted synchrony not consistent with explanations based on S motivation, task difficulty, motor dexterity, a general psychosis factor, drug effects, or tapping speed ability. Deficient motor performance was associated with clinical evidence of abnormal movement and disturbed thinking and with the type-token ratio. (44 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
75.
Mihai Irimia-Vladu Nenad Marjanovic Marius Bodea Gerardo Hernandez-Sosa Alberto Montaigne Ramil Reinhard Schwödiauer Siegfried Bauer Niyazi Serdar Sariciftci Frank Nüesch 《Organic Electronics》2009,10(3):408-415
The transfer of benchtop knowledge into large scale industrial production processes represents a challenge in the field of organic electronics. Large scale industrial production of organic electronics is envisioned as roll to roll (R2R) processing which nowadays comprises usually solution-based large area printing steps. The search for a fast and reliable fabrication process able to accommodate the deposition of both insulator and semiconductor layers in a single step is still under way. Here we report on the fabrication of organic field effect transistors comprising only evaporable small molecules. Moreover, both the gate dielectric (melamine) and the semiconductor (C60) are deposited in successive steps without breaking the vacuum in the evaporation chamber. The material characteristics of evaporated melamine thin films as well as their dielectric properties are investigated, suggesting the applicability of vacuum processed melamine for gate dielectric layer in OFETs. The transistor fabrication and its transfer and output characteristics are presented along with observations that lead to the fabrication of stable and virtually hysteresis-free transistors. The extremely low price of precursor materials and the ease of fabrication recommend the evaporation processes as alternative methods for a large scale, R2R production of organic field effect transistors. 相似文献
76.
Mihaela Badea Rodica Olar Dana Marinescu Gina Vasile Bogdan Jurca Augustin M. Madalan Marius Andruh 《Inorganic chemistry communications》2009,12(6):555-557
The reaction between NiCO3 · Ni(OH)2, acrylic acid and ethylenediamine in a 2:4:1 molar ratio affords the binuclear complex, [Ni2(EDDP)2(H2O)2] · 2H2O 1. The organic ligand, EDDP2? (the dianion of the ethylenediamine-N,N-dipropionic acid ligand), results from the addition of one amine group to the carbon–carbon double bonds of two acrylato ions. The crystal structure of 1 consists of neutral centrosymmetric entities, with the nickel ions connected by two carboxylato groups, each one acting as a monoatomic bridge. The intramolecular Ni?Ni distance is 3.212 Å. The metal ions exhibit an octahedral geometry. The cryomagnetic investigation of 1 reveals an antiferromagnetic coupling of the nickel(II) ions (J = ?21.8 cm?1, H = ?JSNi1SNi2). 相似文献
77.
Bernhard Mitchell Gerhard Peharz Gerald Siefer Marius Peters Tobias Gandy Jan Christoph Goldschmidt Jan Benick Stefan W. Glunz Andreas W. Bett Frank Dimroth 《Progress in Photovoltaics: Research and Applications》2011,19(1):61-72
A spectral beam‐splitting architecture is shown to provide an excellent basis for a four junction photovoltaic receiver with a virtually ideal band gap combination. Spectrally selective beam‐splitters are used to create a very efficient light trap in form of a 45° parallelepiped. The light trap distributes incident radiation onto the different solar cells with an optical efficiency of more then 90%. Highly efficient solar cells including III–V semiconductors and silicon were fabricated and mounted into the light trapping assembly. An integrated characterization of such a receiver including the measurement of quantum efficiency as well as indoor and outdoor I–V measurements is shown. Moreover, the optical loss mechanisms and the optical efficiency of the spectral beam‐splitting approach are discussed. The first experimental setup of the receiver demonstrated an outdoor efficiency of more than 34% under unconcentrated sunlight. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
78.
79.
80.
Lukas Hoehr Felix Reichmann Marius Berndt Johannes Sackmann Norbert Kockmann Werner Karl Schomburg 《化学工程与技术》2019,42(5):971-979
Microreactors offer several advantages compared to the industrial scale when developing new chemical processes. Especially the production and investment costs are low if polymer microreactors are generated by ultrasonic processes. In order to observe the chemical reaction and the flow configuration, these microreactors need to be optically transparent, mechanically stable, and chemically inert to several reagents. The manufacturing process of a transparent polymer plate reactor with a chemically inert surface coating by ultrasonic fabrication is described. Experimental characterization of the microreactors showed that they are leak tight up to a pressure difference of at least 300 kPa and the mixing times are in the range of milliseconds. 相似文献