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131.
132.
The 270MHz NMR spectra of the major sterols of pumpkin seeds show that the configuration at C-24 of 24-ethyl-5α-cholesta-7,22,25-trien-3β-ol and 24-ethyl-5α-cholesta-7,25-dien-3β-ol is 24βF = (24S) whereas the α-spinasterol has the 24αF = (24S) configuration.  相似文献   
133.
The concentration of triterpone glycosides in mature stems of organ pipe cactus was shown to decrease from the surface to the inner portions of the pla  相似文献   
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We determined location and amount of accumulated sand in the gastrointestinal tract (GIT) of rabbits (Oryctolagus cuniculus) and guinea pigs (Cavia porcellus) fed diets containing external (silicate) abrasives. Computed tomographic abdominal images of rabbits (n = 44) and guinea pigs (n = 16) that each received varying numbers (4–7) of different diets for 14 days each (total n = 311 computed tomographs), and radiographs of dissected GIT and presence of silica in GIT content (n = 46 animals) were evaluated. In rabbits, the majority of accumulated sand was located in the caecal appendix, an elongated, intestinal structure in the left side of the abdomen. The ‘wash-back’ colonic separation mechanism in rabbits may be partly responsible for a retrograde transport of sand back to the caecum, where dense, small particles accumulate in the appendix. The appendix likely acted as a reservoir of these particles, leading to significant effects not only of the momentary but also of the previous diet on recorded sand volumes in the rabbits. Guinea pigs have no caecal appendix and a colonic separation mechanism not based on a ‘wash-back’. Less sand accumulation was found in their GIT without a specific location pattern, and there were less previous diet effects in this species. None of the rabbits or guinea pigs developed clinical signs of obstruction during the study, and the recorded sand volumes represented 1.0 ± 1.2% of the 14-d sand intake in rabbits and 0.2 ± 0.2% in guinea pigs. Accumulation of sand in volumes up to 10 cm3 in the GIT of rabbits does not seem to cause clinical health impairment. Large inter-individual differences in rabbits indicate inter-individual variation in proneness to sand accumulation. The reason for the presence of a sand-trapping caecal appendix in animals that are, due to their burrowing lifestyle and feeding close to the ground, predestined for accidental sand ingestion, remains to be unveiled.  相似文献   
136.
Reaction of the toxic and mutagenic alkylating agent mustard gas with DNA of the yeast Saccharomyces cerevisiae was analyzed qualitatively and quantitatively. Within the dose range tested (2 X 10(-5)-2 X 10(-3) M) DNA in vivo is alkylated dose-proportionally. DNA alkylation and relative distribution of purine derivatives are not influenced by the cell's sensitivity towards the mutagen. At LD37 (4.4 X 10(-4) M) the wild type contains 44 300 purine derivatives: 9200 3-alkyladenines (20%), 29600 7-alkylguanines (67%) and 5500 diguaninyl derivates (13%) per genome. In sensitive strains the number of derivates per genome at LD37 is reduced according to the dose reduction factor. Alkylation at the position O6 of guanine by mustard gas cannot be shown, the method's limit of detection being 0.3% amongst purine derivates.  相似文献   
137.
Zusammenfassung Die Verteilung der ABO-Blutgruppen wurde zwischen 680 erstgeborenen und 1232 nachgeborenen Kindern verglichen. Davon stammten 1149 Kinder aus blutgruppenverträglichen und 763 aus unverträglichen Ehen. Die Vermehrung der Blutgruppe 0 und Verminderung der anderen Blutgruppen bei den nachgeborenen Kindern konnte nur bei solchen aus inkompatiblen Ehen gefunden werden. Bei Kindern aus kompatiblen Ehen fand sich ein gegensätzliches Verhalten.
The Varied Distribution of the ABO-Blood Groups in First-Born and Later-Born Children
Summary The ABO blood group distribution was compared in 680 first born and 1232 later born children. Among them 1149 children were from blood group compatible and 763 from incompatible marriages. An increase of 0 and decrease of other blood groups in further children was only seen in children from incompatible marriages. In children from compatible marriages the difference of distribution of blood groups is contrary to the above mentioned result.
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138.
For analysis of trace compounds, stable isotope dilution assays (SIDAs) have gained increasing importance in the past years. This methodology is based on the use of stable isotopically labelled analogues of the analytes as internal standards (IS). To take the mycotoxins patulin and ochratoxin A as examples, the benefits of SIDAs were demonstrated both for foods and for clinical analyses. Regarding PAT, an isotopomer labelled with13C was used as IS and enabled quantitation of the mycotoxin in tissues and blood. By applying this technology, a fast passive diffusion into tissue was proven with the model of the perfused rat stomach. Furthermore, rapid degradation of PAT was observed when it was reacted with blood, which was attributed to the formation of PAT-GSH adducts detected by LC-MS/MS. For OTA, a SIDA was based on the use of [2H5]-OTA as the IS and proved to be more accurate when compared to alternative methods such as HPLC-FD or ELISA. In contrast to PAT, OTA was detectable in human blood and urine samples. Under the assumption that the majority of OTA is circulating in blood, an urinary excretion rate of about 1% of the whole body content per day was calculated. Presented at the 27th Mykotoxin-Workshop, Dortmund, Germany, June 13–15, 2005 Financial support: in part by a grant from the Deutsche Forschungsgemeinschaft (Ry, 19/4-1)  相似文献   
139.
Amoeboid organisms are phylogenetically diverse, some being more closely related to plants or metazoans than to each other. Amoeboid organisms are ecologically successful, having been isolated on all continents, including Antarctica, as well as being the main predators controlling bacterial populations in soil. The classification of these organisms has historically relied upon morphological characteristics. The application of electron microscopy, comparison of enzymic profiles after electrophoretic separation, and analysis of nucleic acid fractions have provided reliable bases for classifying amoeboid organisms. The extent of diversity of these organisms has been recognized, as methods to detect, culture, characterize and identify them has increased. It is reasonable to anticipate that the current 40 000 species of protists will increase substantially as amoeboid organisms are cultivated from poorly accessible niches and from extreme environs.  相似文献   
140.
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