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291.
292.
Jarmila ulcov M. Macek D. Chudoba W. Hubl M. Hill L. Strka 《The Journal of steroid biochemistry and molecular biology》1994,51(5-6):315-318
The results of measurement of 17-hydroxyprogesterone (17-OH-P) in 125 samples of amniotic fluid (AF) from early amniocenteses are presented. The fetuses from all pregnancies studied were unaffected by congenital adrenal hyperphasia caused by 21-hydroxylase deficiency. The AF 17-OH-P level increases slightly but significantly between the 11th and 15th week of gestation, with a maximum in the 14th week. There is no difference between the values measured in male and female fetuses. The AF 17-OH-P levels from the early gestation were compared with those from the 16th–22nd week of pregnancy (published previously). The overall differences of AF 17-OH-P concentrations when considered in all gestational age groups in the whole period 12–22 weeks were statistically insignificant. Thus, the biochemical prenatal diagnosis of congenital adrenal hyperplasia due to 21-hydroxylase deficiency and control of its early fetal treatment could be carried out starting from the end of the first trimester in the same way as at the later period of gestation. 相似文献
293.
Net photosynthetic rate decreased sharply to zero in the range of water potential- 8.0 to -10.4 x 105 Pa. The observed decrease in photosynthetic rate was due not only to the decrease in epidermal conductance, but also to the decrease in intraoellular conductance. Both conductances decreased in the same range of water potential. With decreasing water potential photorespiration rate decreased whereas dark respiration rate remained rather unchanged. Simultaneously CO2 compensation concentration increased. These facts constitute an indirect evidence that water stress inhibited not only transport of CO2 from atmosphere to carboxylation sites in chloroplasts, but also its conversion into photosynthates. 相似文献
294.
Jarmila Solárová 《Biologia Plantarum》1980,22(4):293-293
295.
Cotyledons of 15 day-old seedlings of fiveBrassica oleracea L. varieties were surveyed to identify salient anatomical features. Both palisade parenchyma cells present in the first subepidermal layer and stomata were found to differ in size. 相似文献
296.
Jarmila Novotná 《Biologia Plantarum》1976,18(1):13-18
The blade area and the number of stomata were studied in the cotyledons of five cultivars ofBrassica oleracea L., cultivated in a growth chamber and in the greenhouse, respectively. Characteristic differences between different varieties were found in the number of stomata per unit area as well as in their occurrence on both the adaxial and abaxial surfaces. 相似文献
297.
Jiří Kamler Miloslav Homolka Radim Cerkal Marta Heroldová Jarmila Krojerová-Prokešová Miroslava Barančeková Jan Dvořák Karel Vejražka 《European Journal of Wildlife Research》2009,55(6):583-588
Large herbivores are the key species for game management in the Central Europe. Analyses of factors affecting the feeding
behaviour of herbivores and consequences of their browsing are therefore highly important both for farmers and for game managers
as the protective measurements should be focused on the most threatened fields. The influence of fallow (Dama dama) and roe deer (Capreolus capreolus) browsing during vegetation period on sunflower production was studied. The experiment was carried out in 2006 on a field
located near a forest complex. We marked out pairs of paired permanent plots and monitored deer impact regularly from the
emergence of plants until the harvest. Herbivores damaged the sunflower intensively immediately after the emergence at the
height of 1 to 2 cm above the ground. When the plants had reached approximately 15-40 cm in height, deer browsed the top shoots
and as the plants grew higher the browsing was restricted to leaves or to substitute stems of the previously browsed plants.
Sunflower ceased to attract big herbivores in flowering stage. Browsing significantly affected the yield of seeds. Approximately
one half of the plants that had been damaged in early stage died as well as 12.5% of plants that had been damaged at second
term; the rest produced substitute stems. Almost 33% of the substitute stems did not form disc florets; the second third of
them formed disc florets with a diameter of 6-8 cm, and the last third set disc florets with a diameter of 8-10 cm. 相似文献
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