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101.
102.
Edmund M. Powers Carl Ay Hamed M. El-Bisi Durwood B. Rowley 《Applied microbiology》1971,22(3):441-445
The initial bacteriological requirement established in 1964 for space foods by the U.S. Army Natick Laboratories are: a total aerobic plate count (= 10,000 per g), a total coliform count (= 10 per g), fecal coliforms (negative per gram), fecal streptococci (= 20 per g), coagulase-positive staphylococci (negative in 5 g) and salmonellae (negative in 10 g). Of the space foods and prototypes tested during 1968 and 1969, 93% complied with the total aerobic plate count, 98% had less than 1 coliform per g, and 99% were negative for fecal coliforms; 88% complied with the streptococci requirement; 100 and 98% were negative for staphylococci and salmonellae, respectively. Nineteen food samples which did not comply (as indicated parenthetically by actual counts per gram) with the requirements were (i) total aerobic plate count: beef soup and gravy base (18,000), chicken soup and gravy base (57,000), spaghetti with meat sauce (12,100 and 14,000), sugared coffee (> 300,000), chocolate ice cream cubes (20,000), and each of four samples of chocolate candy (12,000 to 61,000); (ii) coliforms: two out of three vanilla milk drinks (16 and 127) and one beef hash bar (14); (iii) fecal coliforms: one sample of chicken soup and gravy base positive; (iv) fecal streptococci: two samples of peanut cubes (40 and 108), coconut cubes (75), chicken soup and gravy base (2,650), beef soup and gravy base (33), and five out of six flavored milk drinks (23 to 300); (v) salmonellae: one each of chicken and beef soup and gravy base were positive. 相似文献
103.
Ahmet Karada? Ay?egül ?enocak Yusuf Yerli A. Cemil Ba?aran 《Inorganica chimica acta》2009,362(7):2299-278
Two unique bimetalic Pt(II) coordination polymers of composition [Ni(hydeten)2Pt(CN)4] (Ni-Pt) and [Cu(hydeten)2Pt(CN)4] (Cu-Pt) [hydeten = N-(2-hydroxyethyl-ethylenediamine) or 2-(2-aminoethylamino)ethanol] have been synthesized and structurally characterized by various methods in this study. The crystal structure of Cu-Pt was determined by single-crystal X-ray diffraction analysis. The structure of Cu-Pt forms of infinite 2,2-TT type [-Cu(hydeten)2-NC-Pt(CN)2-CN-] chains containing paramagnetic copper atoms bridged by tetracyanoplatinate species. In this complex, Cu(II) centers display an axially elongated octahedron with two chelating hydeten molecules in the equatorial positions and N-bonded bridging cyano groups in the axial positions, whereas Pt(II) centers are four coordinate with four cyanide-carbon atoms in a square-planar arrangement. The decrease of the moments of these complexes in temperature range of 50 305 K can assigned to the antiferromagnetic interactions in the structures. The thermal decomposition of Cu-Pt comprise of five distinguished stages, while the thermal decomposition of Ni-Pt take place four different stages. 相似文献
104.
Ali Metehan Çalışkan Mustafa Nazıroğlu Abdulhadi Cihangir Uğuz İshak Suat Övey Recep Sütçü Ramazan Bal Sıla Çalışkan Ramazan Özcankaya 《The Journal of membrane biology》2010,237(1):51-58
We investigated the effects of acamprosate on alcohol-induced oxidative toxicity, microsomal membrane Ca2+-ATPase (MMCA) activity and N-methyl-d-aspartate receptor (NMDAR) subunits in rat brain. Forty male rats were equally divided into four groups. The first group
was used as control, and the second group received ethanol. Acamprosate and acamprosate plus ethanol each day were administered
to rats constituting the third and fourth groups for 21 days, respectively. Brain cortical and hippocampal samples were taken
from the four groups after 21 days. Brain cortical lipid peroxidation (LP) levels and MMCA activity were higher in the alcohol
group than in control, although glutathione peroxidase (GSH-Px), vitamin C, vitamin E and β-carotene values were lower in
the alcohol group than in control. LP levels were further increased in the acamprosate and alcohol + acamprosate groups compared
with the alcohol group. GSH-Px, vitamin A, vitamin C, vitamin E and β-carotene in the acamprosate and alcohol + acamprosate
groups were further decreased compared with the alcohol group. Hippocampal NMDAR 2A and 2B subunit concentrations were lower
in the alcohol group than in control, although they were increased by acamprosate and alcohol + acamprosate. Brain cortical
MMCA activity was higher in the acamprosate group than in the alcohol-treated rats, although its activity was lower in the
alcohol + acamprosate group than in the acamprosate group. Brain cortical reduced glutathione levels were not found to be
statistically different in any of the groups. Oxidative stress has been proposed to explain the biological side effects of
experimental alcohol intake. Acamprosate and alcohol-induced oxidative stress decreased brain antioxidant vitamins in the
alcoholic rats. 相似文献
105.
Meral E. Kızıltan Ayşegül Gündüz Rahşan Şahin 《Journal of electromyography and kinesiology》2010,20(3):508-512
Our goal was to investigate the characteristics of the auditory brainstem reflexes in patients with hemifacial spasm (HFS) and postparalytic facial syndrome (PFS).The spasm activities and responses by supraorbital and auditory stimuli were recorded from the orbicularis oculi, the posterior auricular and the mentalis muscles in 27 HFS and 21 PFS patients. The results were compared with those of 20 controls.Blink reflex (BR) was obtained by supraorbital stimulation in normal controls and on both sides of HFS and PFS patients whereas sound evoked bilateral auditory blink reflex (ABR) in 96.3%, 90.5% and 100%, respectively. Both BR and ABR showed synkinetic spread on symptomatic sides in all patients. The posterior auricular muscle response (PAMR) was observed bilaterally in 59.3%, 42.9% and 75.0% of groups, respectively. However, there was no synkinetic spread of PAMR.Since PAMR does not show synkinetic spread even in the presence of synkinetic spread of ABR and BR, we may suggest that a distal origin may be responsible of the synkinetic spread, or PAM is probably governed by a smaller nucleus in the brainstem. Thus it may be speculated that its excitability is insufficient to stimulate the ABR nucleus, whereas the reverse process is possible. 相似文献
106.
Background
Computational prediction of functionally related groups of genes (functional modules) from large-scale data is an important issue in computational biology. Gene expression experiments and interaction networks are well studied large-scale data sources, available for many not yet exhaustively annotated organisms. It has been well established, when analyzing these two data sources jointly, modules are often reflected by highly interconnected (dense) regions in the interaction networks whose participating genes are co-expressed. However, the tractability of the problem had remained unclear and methods by which to exhaustively search for such constellations had not been presented.Methodology/Principal Findings
We provide an algorithmic framework, referred to as Densely Connected Biclustering (DECOB), by which the aforementioned search problem becomes tractable. To benchmark the predictive power inherent to the approach, we computed all co-expressed, dense regions in physical protein and genetic interaction networks from human and yeast. An automatized filtering procedure reduces our output which results in smaller collections of modules, comparable to state-of-the-art approaches. Our results performed favorably in a fair benchmarking competition which adheres to standard criteria. We demonstrate the usefulness of an exhaustive module search, by using the unreduced output to more quickly perform GO term related function prediction tasks. We point out the advantages of our exhaustive output by predicting functional relationships using two examples.Conclusion/Significance
We demonstrate that the computation of all densely connected and co-expressed regions in interaction networks is an approach to module discovery of considerable value. Beyond confirming the well settled hypothesis that such co-expressed, densely connected interaction network regions reflect functional modules, we open up novel computational ways to comprehensively analyze the modular organization of an organism based on prevalent and largely available large-scale datasets.Availability
Software and data sets are available at http://www.sfu.ca/~ester/software/DECOB.zip. 相似文献107.
The pine caterpillar Thaumetopoea pityocampa (Lepidoptera: Thaumetopoeidae) is found in pine woods. Hairs of the T. pityocampa caterpillar cause a cutaneous reaction in humans and animals. Mast cells are responsible for allergic reactions in mammals. In this study male swiss albino mice were divided into two groups: 5 mice in the control group and 25 mice in the experimental group. The dorsal skin of mice was shaved. The mice in the experimental group and T. pityocampa larvae (fifth instar, approximately n=100) were put in the same cage. Dermal mast cells of mice exposed to T. pityocampa were examined with a transmission electron microscope and compared to the control group 1, 3, 6, 12 and 24 hours after exposure. Dermal mast cell degranulation in mice was observed 12 and 24 hours after exposure. 相似文献
108.
Atomic force microscopy has been employed to compare the adhesion of Navicula species I diatoms to surfaces of a hydrophobic elastomer, Intersleek, and a hydrophilic mineral, mica. This was accomplished using tipless atomic force microscopy cantilevers functionalized with live diatom cells. Both surfaces were tested with the same diatom bioprobe. Force versus distance curves generated during these experiments revealed comparable cell adhesion strengths on Intersleek and mica, indicating that Navicula diatoms secrete extracellular polymeric substances with hydrophobic and hydrophilic properties. A statistical analysis of force curves was carried out and the average values of works of detachment of a diatom from Intersleek and mica surfaces were determined. 相似文献
109.
Different doses of irradiation were performed in which group 1 (non-irradiated), group 2 (8 Gy/single dose/whole body) and group 3 (15 Gy/single dose/whole body) were formed of guinea pigs. After 24 hr of radiation exposure the levels of lipid peroxidation product, malondialdehyde, (MDA), glutathione (GSH) and activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) were measured in the whole kidney. The MDA content increased in animals irradiated with 8 and 15 Gy. And group 3 showed an increase the level of MDA. GSH contents of kidney in group 2 and 3 increased. The activity of SOD decreased markedly in group 3 when compared with control group. The activity of GSH-Px decreased significantly in group 2 and group 3 in comparison to controls. It may be concluded that a high dose of ionizing irradiation cause excessive oxidative stress in kidney. 相似文献
110.