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131.

Background

Fruit has since long been advocated as a healthy source of many nutrients, however, the high content of sugars in fruit might be a concern.

Objectives

To study effects of an increased fruit intake compared with similar amount of extra calories from nuts in humans.

Methods

Thirty healthy non-obese participants were randomized to either supplement the diet with fruits or nuts, each at +7 kcal/kg bodyweight/day for two months. Major endpoints were change of hepatic fat content (HFC, by magnetic resonance imaging, MRI), basal metabolic rate (BMR, with indirect calorimetry) and cardiovascular risk markers.

Results

Weight gain was numerically similar in both groups although only statistically significant in the group randomized to nuts (fruit: from 22.15±1.61 kg/m2 to 22.30±1.7 kg/m2, p = 0.24 nuts: from 22.54±2.26 kg/m2 to 22.73±2.28 kg/m2, p = 0.045). On the other hand BMR increased in the nut group only (p = 0.028). Only the nut group reported a net increase of calories (from 2519±721 kcal/day to 2763±595 kcal/day, p = 0.035) according to 3-day food registrations. Despite an almost three-fold reported increased fructose-intake in the fruit group (from 9.1±6.0 gram/day to 25.6±9.6 gram/day, p<0.0001, nuts: from 12.4±5.7 gram/day to 6.5±5.3 gram/day, p = 0.007) there was no change of HFC. The numerical increase in fasting insulin was statistical significant only in the fruit group (from 7.73±3.1 pmol/l to 8.81±2.9 pmol/l, p = 0.018, nuts: from 7.29±2.9 pmol/l to 8.62±3.0 pmol/l, p = 0.14). Levels of vitamin C increased in both groups while α-tocopherol/cholesterol-ratio increased only in the fruit group.

Conclusions

Although BMR increased in the nut-group only this was not linked with differences in weight gain between groups which potentially could be explained by the lack of reported net caloric increase in the fruit group. In healthy non-obese individuals an increased fruit intake seems safe from cardiovascular risk perspective, including measurement of HFC by MRI.

Trial Registration

ClinicalTrials.gov NCT02227511  相似文献   
132.
Summary The authors examined the karyotype of 89 out of the 102 men 180 cm (511) tall or more among the 459 male inmates of four Swedish institutions for alcoholics. All 89 had a normal chromosome constitution.  相似文献   
133.
Phytochrome from oats ( Avena sativa L. cv. Sol II), partially purified on brushite, was immobilized on Sepharose beads to which antiphytochrome immunoglobulin had been covalently linked. The immobilized phytochrome was first brought to the Pr form with unpolarized far-red light. The change in linear dichroism at 660 nm induced by plane polarized red light, and its reversal by plane polarized far-red light were then studied using a dual-wavelength spectrophotometer equipped with polarizing filters. The far-red light was most effective in reversing red-induced dichroism when the angle between the planes of polarization of red and far-red light was approximately 23°. From this it was computed that the long-wavelength transition moment of phytochrome rotates about 29° (or 180°–29°) with respect to the protein during conversion from Pr to Pfr. The reverse experiment, using unpolarized red light followed first by polarized far-red light and then polarized red light, with dichroism monitored at 730 nm, also gives most effective reversal for an angle of about 23° between polarization planes, but this corresponds to a transition moment rotation of about 36° (or 180°–36°). The present method is more straightforward but less accurate and confirms our earlier conclusion that the rotation angle is close to 32° (or 180°–32°) in contrast to the "in vivo" value of 90° found by several workers.  相似文献   
134.
135.
Aqueous solutions of 4-O-methyl-D-glucuronic acid at pH 7 were heated at 100°, and the monocarboxylic acids formed by isomerization were separated by anion-exchange chromatography and further identified by gas-liquid chromatography-mass spectrometry. After 6 h, the following yields of acids were obtained: 3-O-methyl-D-lyxo-5-hexulosonic (47%), 3-O-methyl-L-ribo-5-hexulosonic (12%), 4-O-methyl-D-mannuronic (4%), and 3-O-methyl-L-ribo-4-hexulosonic (1%).  相似文献   
136.
Rabbits were given repeated injections of cadmium chloride. Cadmium- and zinc-containing protein fractions were obtained from the livers of these animals by precipitation procedures and Sephadex G-75 chromatography. The protein thus obtained showed several characteristics similar to those of the earlier described protein metallothionein. Further separation by isoelectric focusing showed two main protein peaks with isoelectric points at 3.9 and 4.5 respectively. Amino acid analysis of these two forms showed similar content of most amino acids [residues per cent.: cysteine (28%), aspartate (8%), threonine (5–6%), serine (12%), glycine (7%), alanine (13%), methionine (2%), isoleucine (2%)] but with a small difference in content of lysine (12 and 13% respectively), proline (9 and 5% respectively) and glutamate (2 and 4% respectively). The two forms of the protein both contained cadmium, but only the one with pI4.5 contained also significant amounts of zinc.  相似文献   
137.
The sudden changes in the rates of transpiration and water uptake which occurred when the osmotic potential of the nutrient solution surrounding the roots of young wheat plants was rapidly changed were studied. The transpiration was measured by the aid of the microwave hygrometer and the water uptake by a recording poto-meter specially built for this investigation. When the osmotic potential of the nutrient solution was rapidly increased by adding mannitol, there was a temporary transpiration increase. The maximum increase was greater but the total time of the temporary increase shorter when a higher mannitol concentration was used. The quantity of water transpired by the shoots due to the temporary transpiration increase seemed to be fairly constant irrespectively of the mannitol concentration. The water transport to the shoots was immediately reduced when the osmotic potential was rapidly increased. The immediate reduction was greater when a higher mannitol concentration was used. After the immediate reduction the rate of water transport increased without delay. When the osmotic potential of the nutrient solution was rapidly decreased by withdrawing mannitol there was a temporary transpiration decrease, and the water transport to the shoots was immediately increased. After this increase the rate of water transport started to decrease at once. When, however, the mannitol concentration had been 0.30 M or higher, the transpiration rate increased progressively, and the change of the rate of water transport was small. The results indicate that the primary effect of the rapidly changed osmotic potential is localized to the root surface. The rapidly reduced water transport to the shoots after adding mannitol brings about the temporary transpiration increase. The course of events after withdrawing mannitol is just the reverse to that when adding mannitol.  相似文献   
138.
A controversy has surrounded the questions of whether or not guanosine tetraphosphate (ppGpp) is a specific inhibitor of bacterial rRNA and tRNA synthesis, especially during normal exponential growth, and whether the RNA polymerase is the target of ppGpp action. To answer these questions, a pBR322-derived plasmid, pKT28, was constructed that carries the Escherichia coli relA gene encoding a ppGpp synthetase under control of the lacUV5 promoter. The plasmid was used to transform the ppGpp reporter strain VH271 in which expression of beta-galactosidase from an rrnB P1 promoter is inhibited by ppGpp. In the presence of high concentrations of lac inducer, bacteria of the transformed strain accumulate ppGpp with the result that synthesis of rRNA and beta-galactosidase is inhibited and growth ceases. At low concentrations of inducer, growth is only reduced and cells form small white colonies on X-gal indicator plates. After continued incubation, these colonies form blue sectors of faster growing mutant cells. Phage P1 transduction experiments showed that these mutants have mutations cotransducing with rpoB, the gene encoding the beta-subunit of RNA polymerase. One particular mutant strain, KT13, had acquired partial resistance to ppGpp inhibition of rRNA synthesis. The mutation in this strain was cloned by in vivo recombination into an rpoB plasmid. The presence of this plasmid conferred increased resistance to overproduction of ppGpp. These results suggest that ppGpp is a specific inhibitor of rRNA synthesis, even in the absence of amino acid starvation, and that RNA polymerase is involved as the target of ppGpp action.  相似文献   
139.
The pericarp has been studied in 72 taxa belonging to the genera Leucas, Leonotis, Acrotome, Otostegia and Isoleucas. Otostegia, Isoleucas and many Leucas (the Asiatic sections Astrodon, Leucas, Plagiostoma , and the African Spiculifolia, Squarrosicyme, Stachydiformis and Virgata ) have been found to agree with most other members of the subfamily Lamioideae by having high bone cells which contain crystals. Acrotome, Leonotis and most African Leucas (sections Hemistoma, Lasiocotys, Lonostoma, Neuflizeana, Ogadenia and Physoleucas ) deviate by having thin bone cells which often lack crystals, and due to their similarity, these African taxa are suggested to be closely related. The Asiatic Leucas (Ortholeucas), Plagiostoma and Astrodon also seem to form a group. Leucas milanjiana and perhaps also Leucas hyssopifolia are considered to be extraneous to Plagiostoma and to be more closely related to the section Leucas and the African Lasiocorys, Ogadenia and Physoleucas respectively.  相似文献   
140.
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