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61.
62.
The use of tissue expander base as an internal nasal splint 总被引:3,自引:0,他引:3
Eroğlu L Güneren E Akbaş H Demir A Karacalar A 《Plastic and reconstructive surgery》2003,111(2):942-943
63.
Baydar T Papp A Aydin A Nagymajtenyi L Schulz H Isimer A Sahin G 《Biological trace element research》2003,92(3):231-244
The present study was undertaken to examine possible aluminum (Al) accumulation in the brain of rats and to investigate whether
subchronic exposure to the metal leads to behavioral and neurophysiological changes in both treated and control groups. Each
of the groups consisted of 10 animals. Aluminum chloride (AlCl3) at a low (50 mg/kg/d) or high (200 mg/kg/d) dose was applied to male Wistar rats by gavage for 8 wk. Al-free water by gavage
was given to the control group throughout the experiment. Behavioral effects were evaluated by open-field (OF) motor activity
and by acoustic startle response (ASR). Electrophysiological examination was done by recording spontaneous activity and sensory-evoked
potentials from the visual, somatosensory, as well as auditory cortex. The Al content of each whole brain was determined by
electrothermal atomic absorption spectrophotometry. Subchronic Al exposure slightly caused some changes in the evoked potentials
and electrocorticograms and in the OF and ASR performance, but these results were not statistically significant. The brain
Al levels of the control and the low and high dose of Al-exposed groups were measured as 0.717±0.208 μg/g (wet weight), 0.963±0.491
μg/g (wet weight) and 1.816±1.157 μg/g (wet weight), respectively. 相似文献
64.
Oztürk A Baltaci AK Bediz CS Mogulkoc R Güngör S 《Biological trace element research》2003,96(1-3):255-262
The present study was designed to investigate the effects of zinc and/or melatonin deficiency on rat testes. A total of 24
adult male Sprague-Dawley rats were used in this study. The rats were divided into four groups of six rats each, as follows:
(I) controls, (II) zinc deficient, (III) pinealectomized, zinc normal, and (IV) pinealectomized, zinc deficient. The plasma
zinc levels in the control group were higher than in all the other groups (p<0.01), and those of the zinc-deficient groups II and IV were significantly lower than for group III (p<0.01). The melatonin levels in the controls were also significantly higher than for all other groups (p<0.01) There was no significant difference in sperm production between the controls and the group of animals that had no epiphysis.
A significant suppression was observed in the spermatogenetic activity of the zinc-deficient groups (p<0.01). The suppression was higher in group II than in group IV. These results indicate that testicular damage caused by zinc
deficiency may be reduced by melatonin deficiency. 相似文献
65.
Ozturk A Baltaci AK Mogulkoc R Oztekin E Sivrikaya A Kurtoglu E Kul A 《Biological trace element research》2003,94(2):157-166
The aim of the study was to investigate the effects of zinc deficiency and supplementation on lipid peroxidation and glutathione
levels in blood and in some tissues of rats performing swimming exercise. Forty adult male Sprague-Dawley rats were divided
into four groups: group 1, zinc-deficient consisted of swimming rats; group 2 consisted of zinc-supplemented swimming rats;
groups 3 and 4 were the swimming and nonswimming controls, respectively. The levels of malondialdehyde and glutathione were
measured after 4 wk of zinc-deficient or zinc-supplemented diet and 30 min of swimming exercise daily.
The erythrocyte glutathione levels of groups 2 and 4 were significantly higher than those of groups 1 and 3 (p<0.01). The plasma malondialdehyde level of group 1 was significantly higher than all other groups. The glutathione levels
in liver, kidney, striated muscle, and testes of group 2 were higher than in the other groups (p<0.01) and higher in kidney and striated muscle of group 3 than in groups 1 and 4 (p<0.01). The tissue malondialdehyde levels of striated muscle, liver, kidney, and testes of group 1 were significantly higher
than for all other groups (p<0.01). Our findings suggest that both swimming exercise and zinc deficiency result in an increase of lipid peroxidation in
tissues and that zinc supplementation prevents these alterations by the activation of the antioxidant system. 相似文献
66.
We investigated the serum concentrations of zinc and copper during the inflammatory process together with the effect of treatment
with a nonsteroid anti-inflammatory agent on these trace elements concentrations. In the present study, we used 92 guinea
pigs, 12 of which constituted the control group; the remaining 80 were the experimental group. To start with, proquazone (as
anti-inflammatory agent) was administered orally to 40 guinea pigs of the experimental group at 20-mg/kg doses 2 h before
the surgery. Throughout the experimental period, the above dose was administered to the animals twice a day. We produced inflammation
in all animals of the experimental group by using carrageenan (inflammatory agent) dropped into mandibular surgical defects.
Serum concentrations of zinc and copper were determined by atomic absorption spectrophotometry in both groups at the 6th,
48th, 120th, 168th, and 240th h. The serum zinc concentrations of the carrageenan-administered group decreased significantly
(p<0.01). When comparing the serum zinc concentrations of the carrageenan plus proquazone-administered group with those of control
group, the decrease (p<0.05) at the 6th, 48th, and 120th h were statistically significant. When the copper serum concentrations of the carrageenan-administered
group were compared with those of the control group, at the 48th, 120th, and 168th h, a statistically significant increase
(p<0.01) was observed. However, there was no significant change in the carrageenan plus proquazone-administered group at the
168th and 240th h. As a result during the acute phase of inflammation, serum zinc concentrations decreased, whereas serum
copper concentrations increased. The alterations in zinc concentrations were more rapid than those in copper concentrations,
but the administration of proquazone slowed the rate of decrease in serum zinc concentrations.
This work was presented at the Fourth International Congress of Pathophysiology, June 29–July 5, 2002, Budapest, Hungary. 相似文献
67.
Sezai Ercisli Ahmet Esitken Rustem Cangi Fikrettin Sahin 《Plant Growth Regulation》2003,41(2):133-137
During the winters of 2001 and 2002, the effects of three strain of Agrobacterium rubi (A1, A16 and A18), a range of IBA concentrations (0, 2000, 4000 and 6000 ppm) alone and in combination with three strains of Agrobacterium rubi and date of cutting collection on the rooting of hardwood stem cuttings of kiwifruit cv. Hayward were evaluated. Treatments of hardwood stem cuttings of kiwifruit cv. Hayward with the bacteria, IBA and IBA plus bacteria were found to promote rooting. Highest rooting percentage was obtained from cuttings treated with 4000 ppm IBA plus A18 in cv. Hayward in both years. Higher rooting percentages were observed when shoots were collected in February rather than in January. 相似文献
68.
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