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91.
92.
This study aims to investigate how intercropping of oat (Avena sativa L.) with white lupin (Lupinus albus L.) affects the mobile fractions of trace metals (Fe, Mn, Pb, Cd, Th, U, Sc, La, Nd, Ge) in soil solution. Oat and white lupin were cultivated in monocultures and mixed cultures with differing oat/white lupin ratios (11% and 33% lupin, respectively). Temporal variation of soil solution chemistry was compared with the mobilization of elements in the rhizosphere of white lupin and concentrations in plant tissues. Relative to the monocrops, intercropping of oat with 11% white lupin significantly increased the concentrations of Fe, Pb, Th, La and Nd in soil solution as well as the concentrations of Fe, Pb, Th, Sc, La and Nd in tissues of oat. Enhanced mobility of the mentioned elements corresponded to a depletion of elements in the rhizosphere soil of white lupin. In mixed cultures with 33% lupin, concentrations in soil solution only slightly increased. We conclude that intercropping with 11% white lupin might be a promising tool for phytoremediation and phytomining research enhancing mobility of essential trace metals as well as elements with relevance for phytoremediation (Pb, Th) and phytomining (La, Nd, Sc) in soil.  相似文献   
93.
The present study sought to examine the effect of 5 weeks of training with minimalist footwear on oxygen consumption during walking and running. Thirteen college-aged students (male n = 7, female n = 6, age: 21.7±1.4 years, height: 168.9±8.8 cm, weight: 70.4±15.8 kg, VO2max: 46.6±6.6 ml·kg−1·min−1) participated in the present investigation. The participants did not have experience with minimalist footwear. Participants underwent metabolic testing during walking (5.6 km·hr−1), light running (7.2 km·hr−1), and moderate running (9.6 km·hr−1). The participants completed this assessment barefoot, in running shoes, and in minimalist footwear in a randomized order. The participants underwent 5 weeks of training with the minimalist footwear. Afterwards, participants repeated the metabolic testing. Data was analyzed via repeated measures ANOVA. The analysis revealed a significant (F4,32= 7.576, ηp2=0.408, p ≤ 0.001) interaction effect (time × treatment × speed). During the initial assessment, the minimalist footwear condition resulted in greater oxygen consumption at 9.6 km·hr−1 (p ≤ 0.05) compared to the barefoot condition, while the running shoe condition resulted in greater oxygen consumption than both the barefoot and minimalist condition at 7.2 and 9.6 km·hr−1. At post-testing the minimalist footwear was not different at any speed compared to the barefoot condition (p> 0.12). This study suggests that initially minimalist footwear results in greater oxygen consumption than running barefoot, however; with utilization the oxygen consumption becomes similar.  相似文献   
94.
Granzyme B is released from CTLs and NK cells and an important mediator of CTL/NK-induced apoptosis in target cells. The human intracellular serpin proteinase inhibitor (PI)9 is the only human protein able to inhibit the activity of granzyme B. As a first step to elucidate the physiological role of PI9, PI9 protein expression in various human tissues was studied. A mAb directed against human PI9 was developed, which specifically stained PI9-transfected COS-7 cells, and was used for immunohistochemistry. Both in primary lymphoid organs and in inflammatory infiltrates, PI9 was present in different subsets of dendritic cells. Also T-lymphocytes in primary and organ-associated lymphoid tissues were PI9 positive. Endothelial cells of small vessels in most organs tested as well as the endothelial layer of large veins and arteries showed strong PI9 staining. Surprisingly, high PI9 protein expression was also found at immune-privileged sites like the placenta, the testis, the ovary, and the eye. These data fit with the hypothesis that PI9 is expressed at sites where degranulation of CTL or NK cells is potentially deleterious.  相似文献   
95.
Grooming in dyads of six captive female hamadryas baboons (Papio hamadryas) was analysed. Each dyad was observed in isolation and as part of a group of three to six females. The isolated dyads differed from dyads in groups, as follows. (1) Grooming in isolated dyads mainly depended on the actor's general tendency to groom, whereas actors in groups were more responsive to who the recipient was. (2) In groups, grooming tended to be more frequent among females of high dominance rank and among females who preferred one another in choice tests. The opposites were true for isolated dyads. Females in isolated dyads seemed to use grooming to improve a poor relationship, whereas grooming in groups was used as if to maintain and defend a valuable relationship.  相似文献   
96.
A 2 × 2 factorial experiment was conducted between April and August 2001 to evaluate the effects of NaCl on Oreochromis niloticus growth and water quality in twelve 0.015 ha limed ponds. The design involved fertilizer and salt as factors with two treatments for each factor. Each salt‐fertilizer combination was replicated three times and fish were not offered external food during the 98 days culture. Growth of O. niloticus was significantly enhanced by salt at higher fertilizer level but not at the lower fertilization level. Although salt had no direct effect on fish growth, a significant salt‐fertilizer interaction was demonstrated. Water quality variables, with a few exceptions, were similar among the salted treatments. Total ammonia increased significantly with fertilization level, but the values were similar in salted and unsalted treatments at the same fertilizer level. Total nitrogen was higher in the salted than unsalted treatments while the organic matter content was lower in the salted treatments. The reasons for the better growth of O. niloticus, are discussed with respect to water quality variables. The present results suggest that fertilization rates of 20 kg N ha?1 may have negative effects on fish growth. However, presence of sodium chloride seems to reduce these negative effects.  相似文献   
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98.

Background  

Arcobacter spp. are a common contaminant of food and water, and some species, primarily A. butzleri and A. cryaerophilus, have been isolated increasingly from human diarrheal stool samples. Here, we describe the first Arcobacter multilocus sequence typing (MLST) method for A. butzleri, A. cryaerophilus, A. skirrowii, A. cibarius and A. thereius.  相似文献   
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