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1.
The emergence of memory, a trace of things past, into human consciousness is one of the greatest mysteries of the human mind. Whereas the neuronal basis of recognition memory can be probed experimentally in human and nonhuman primates, the study of free recall requires that the mind declare the occurrence of a recalled memory (an event intrinsic to the organism and invisible to an observer). Here, we report the activity of single neurons in the human hippocampus and surrounding areas when subjects first view cinematic episodes consisting of audiovisual sequences and again later when they freely recall these episodes. A subset of these neurons exhibited selective firing, which often persisted throughout and following specific episodes for as long as 12 seconds. Verbal reports of memories of these specific episodes at the time of free recall were preceded by selective reactivation of the same hippocampal and entorhinal cortex neurons. We suggest that this reactivation is an internally generated neuronal correlate for the subjective experience of spontaneous emergence of human recollection.  相似文献   
2.
The potent odorant beta-damascenone was formed directly from 9'-cis-neoxanthin in a model system by peroxyacetic acid oxidation and two-phase thermal degradation without the involvement of enzymatic activity. Beta-damascenone formation was heavily dependent on pH (optimum at 5.0) and temperature, occurring over the two sequential phases. The first was incubation with peroxyacetic acid at 60 degrees C for 90 min, and the second was at above 90 degrees C for 20 min. Only traces of beta-damascenone were formed on application of only one of the two phases. Formate and citrate solutions produced a much better environment for beta-damascenone formation than acetate and phosphate. About 7 microg/L beta-damascenone was formed from 5.8 mg/L 9'-cis-neoxanthin under optimal experimental condition. The detailed pathway by which beta-damascenone is formed remains to be elucidated.  相似文献   
3.
Buffalo milk represents an indispensable source of nourishment in many parts of the world and it is the second most consumed milk worldwide. Buffalo milk is actually used for the production of many dairy products such as pasteurized or concentrated milk, butter, yogurt, ice‐cream, dehydrated milk products and cheeses. Due to its high nutritional value and the presence of natural bioactive substances, buffalo milk can also provide health benefits to consumers. In Italy, buffalo milk is used mainly for cheese making, mozzarella PDO (Protected Designation of Origin), which is a highly valued dairy product. This 3‐year study, carried out between 2011 and 2013, was aimed at evaluating the quality of bulk Italian Mediterranean buffalo milk by monitoring physico‐chemical parameters, somatic cell and total bacterial counts. A total of 51 samples of bulk milk were collected from one herd throughout the monitored period. Analysis of variance, carried out to test month, season and year main effects, highlighted remarkable seasonal effects for fat, protein and lactose content, as well as for predicted mozzarella cheese yield, and somatic cell counts. The calculation of simple correlations allowed the identification of positive correlations between estimated cheese yield and fat and protein content.  相似文献   
4.
The roots of Rumex bucephalophorus, collected in Israel, were analyzed for trans-stilbenes. Two stilbene-O-glycosyl derivatives were identified, in addition to 3,5,4'-trihydroxystilbene (1) (resveratrol). The stilbene-O-glycosyl derivatives were 5,4'-dihydroxystilbene-3-O-beta-d-glucopyranoside (2) (piceid) and the new 5,4'-dihydroxystilbene-3-O-alpha-arabinopyranoside (3), which is being named rumexoid. The structure of rumexoid was elucidated by using spectroscopic data. The antioxidant capacities of stilbenoids 1-3 were determined and expressed as trolox equivalent antioxidant capacity (TEAC). TEAC value for trans-resveratrol was highest (2.7) and for rumexoid lowest (1.5). In vitro, trans-resveratrol and rumexoid demonstrated a potent inhibitory effect on alpha-glucosidase activity (IC50 < 0.1 and < 0.5 mM, respectively). The commercial antidiabetic agent acarbose was shown to inhibit only 35% of the enzyme activity at 0.5 mM. The addition of piceid to the reaction mixture did not inhibit alpha-glucosidase in vitro in the range of concentrations used. These findings extend the range of reported beneficial effects of stilbene derivatives, and demonstrate the multifaceted activities that dietary polyphenols may exert in the intestine, where their concentrations are highest in the body.  相似文献   
5.
The cultivars Ori, Idit, Zohar, and Zahov have been bred specifically for adaptation to the Mediteranean climate: Ori and Idit are early tablestock cultivars, Idit is suited for “mini potatoes” (20 to 35 mm in diameter); Zohar is a midseason tablestock cultivai-, and Zahov is used as an early chipstock cultivar. The cultivars can be grown in either of the two main seasons in the Mediterranean region: the spring season (January through July) and the winter season (September through March). The cultivars have rapid emergence and early tuber set, they are tolerant to high temperatures and drought, and are not susceptible to external or internal defects. In field experiments, Idit yields were lower than the cultivar checks (Alpha, Nicola, or Desiree) in six of seven trials. However, the attractive appearance of the small oval tubers (20-35 mm in diameter) and the good aroma of the baked tubers are advantages. Yield of Ori and Zohar occasionally exceeded those of cultivar checks, and their yellowish skin, especially in sandy soils, is an advantage. Yields and tuber dry matter content of the early-maturing cultivar Zahov were similar to Hermes, a standard chipstock cultivar commonly used in Israel. The early maturation of Zahov is desirable to extend the harvest season.  相似文献   
6.
Haematological, ocular and skeletal abnormalities were documented in a samoyed male and its five offspring. Haematological abnormalities, found in repeated tests in all the dogs, included marked eosinophilia, eosinophilic bands and absence of Barr bodies. Two of the dogs had bilateral buphthalmia, retinal detachments and other ocular abnormalities. Three of the dogs had skeletal abnormalities including chondrodysplasia (dwarfism) and brachygnathia (undershot jaw). A similar combination of inherited skeletal and ocular disorders, without the haematological abnormalities, has been described in samoyeds. Acquired causes for the haematological findings, which are similar to the inherited Pelger-Huët anomaly described in several species, have been eliminated. Eosinophilic bands and scarcity of Barr bodies could be a marker, or a previously unreported manifestation, of an inherited disorder in samoyeds.  相似文献   
7.
Structural materials in nature exhibit remarkable designs with building blocks, often hierarchically arranged from the nanometer to the macroscopic length scales. We report on the structural properties of biosilica observed in the hexactinellid sponge Euplectella sp. Consolidated, nanometer-scaled silica spheres are arranged in well-defined microscopic concentric rings glued together by organic matrix to form laminated spicules. The assembly of these spicules into bundles, effected by the laminated silica-based cement, results in the formation of a macroscopic cylindrical square-lattice cagelike structure reinforced by diagonal ridges. The ensuing design overcomes the brittleness of its constituent material, glass, and shows outstanding mechanical rigidity and stability. The mechanical benefits of each of seven identified hierarchical levels and their comparison with common mechanical engineering strategies are discussed.  相似文献   
8.
An 11‐year‐old male Labrador retriever dog with chronic recurrent complicated urinary tract infection due to Escherichia coli and a history of prolonged multi‐drug chemotherapeutic protocol due to lymphoma was diagnosed with emphysematous cystitis. Diagnosis was based on ultrasonographic and radiographic findings. The immunosuppressive effects of the long glucocorticoid treatment were probably the main underlying mechanism involved in the pathogenesis, however, chemotherapy and/or the presence of lymphoma might have also been involved.  相似文献   
9.
The records of five dogs diagnosed with spirocercosis-associated pyothorax were retrospectively reviewed. On admission, the most common clinical findings were weakness, anorexia, depression, dyspnoea and fever. All dogs had typical oesophageal Spirocerca lupi granulomas. Contrast thoracic radiography revealed contrast material leakage from the oesophagus into the pleural cavity in two dogs only. All dogs were medically treated with broad-spectrum antibiotics, repeated chest tube drainage and thoracic lavage, and four of the dogs were treated with doramectin. One dog was euthanased due to a concurrent non-related disease at the owners request while the remaining four survived. S. lupi infection should be included in the differential diagnoses of canine pyothorax in endemic areas. Conservative medical management of pyothorax with antihelmintic medication was shown to be effective in the treatment of S. lupi-associated pyothorax.  相似文献   
10.
Summary The response of several potato cultivars to salinity levels of 20.5, 34.2 and 51.3 mM NaCl was investigated. Salinity tended to lower the water and the osmotic potentials of leaves and tubers while increasing the content of total soluble solids and of proline; it also increased the content of dry matter in the tubers and reduced tuber yields. Susceptibility to salinity was described by the relative loss of tuber dry weight. ‘Blanka’ tolerated the lowest NaCl level (20.5 mM) and exhibited moderate tolerance to higher levels when exposed to salinity stress for 37 days.before harvest, but was susceptible when exposed to the higher levels for 63 days. Cv. Alpha showed moderate tolerance, loosing up to 15% of tuber dry weight when exposed to salinity levels of 20.5 and 34.2 mM NaCl. Mechnisms involved in the adaptation of potatoes to salinity stress are discussed. Contribution from the Agricultural Research Organization, The Volcani Center, Bet Dagan, Israel. No. 2206-E, 1987 series.  相似文献   
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