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491.
State‐of‐the‐art image‐processing methods offer new possibilities for diagnosing diseases using scattered light. The optical diagnosis of rheumatism is taken as an example to show that the diagnostic sensitivity can be improved using overlapped pseudocolored images of different wavelengths, provided that multispectral images are recorded to compensate for any motion‐related artefacts that occur during examination. (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
492.
Bryozoans are among the most important groups of the Southern Ocean benthic macrofauna, both in terms of species richness and abundance. However, there is a considerable lack of ecological research focused on their distribution patterns and species richness on smaller scale, especially in the soft bottom habitats of Antarctic glacial fjords. The aim of this study was to describe those patterns in the Admiralty Bay. Forty-nine Van Veen grab samples were collected at the depth range from 15 to 265 m, in the summer season of 1979/1980, at three sites distributed along the main axis of the fjord. Among 53 identified species of bryozoans, 32 were recorded in the Admiralty Bay for the first time. The most common and abundant species were Himantozoum antarcticum, Inversiula nutrix and Nematoflustra flagellata. Genera such as Arachnopusia, Cellarinella and Osthimosia were the most speciose taxa. It was demonstrated that depth was important for the distribution of the bryozoans. More than half of the recorded species were found only below 70 m. An influence of glacial disturbance was reflected in the dominance structure of colony growth-forms. The inner region of the fjord was dominated almost entirely by encrusting species, while the diversity of bryozoan growth-forms in less disturbed areas was much higher. In those sites the highest percentage of branched, tuft like species represented by buguliform and flustriform zoaria was observed. 相似文献
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495.
Estrogen sulfotransferase of the rat liver: complementary DNA cloning and age- and sex-specific regulation of messenger RNA. 总被引:7,自引:0,他引:7
W F Demyan C S Song D S Kim S Her W Gallwitz T R Rao M Slomczynska B Chatterjee A K Roy 《Molecular endocrinology (Baltimore, Md.)》1992,6(4):589-597
Mammalian estrogen sulfotransferase (EST; EC 2.8.2.4) sulfurylates the hydroxyl group of estrogenic steroids by transferring the sulfate from a cosubstrate adenosine 3'-phosphate-5'-phosphosulfate. Sulfurylated steroids do not bind to the estrogen receptor with high affinity and, therefore, are hormonally inactive. We have purified rat liver EST and developed monoclonal antibody to this enzyme. By immunoscreening a lambda gt-11 expression library constructed from male rat liver cDNAs, the cDNA clone corresponding to EST was identified and isolated. A recombinant expression plasmid (pCMV5) containing this cDNA insert when transfected into COS-7 cells generated both immunologically and enzymatically active EST. With the help of this cDNA probe, we have explored the regulation of the EST mRNA in the liver and the possible role of this enzyme in sex hormone action. During the lifespan of male rats, only the young adult animals show hepatic androgen responsiveness. Also, estrogenic hormones strongly antagonize androgen action in the rat liver. Northern blot analysis of liver RNA derived from male rats of different ages shows that the androgen sensitivity of young adult animals is associated with a high expression of EST mRNA. During the same period, mRNA corresponding to dehydroepiandrosterone sulfotransferase is markedly (approximately 10-fold) down-regulated. Such a correlation is in concordance with the role of these enzymes in the maintenance of hepatic androgen sensitivity during young adult life by inactivating the estrogenic and sparing the androgenic steroids. Furthermore, the increase in the hepatic androgen sensitivity of androgen-treated female rats is also associated with the induction of EST.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
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497.
Lukasz Wator Urszula Razny Adriana Balwierz Anna Polus Hans G. Joost Grzegorz Dyduch Romana Tomaszewska Aldona Dembinska-Kiec 《Genes & nutrition》2008,3(3-4):177-180
Leptin is prompt to drive angiogenesis, effecting proper vascularisation. Tissue remodeling (including adipose organ) is associated with the angiogenic response. The aim of this study was to investigate the effect of hyperleptinemia on angiogenesis in subcutaneous (s.c.) in vivo matrigel model in mice on a high fat (HF) diet. HF promoted adipose tissue accumulation and biochemical changes resembling metabolic syndrome. However, the impact of this dietary treatment on angiogenesis, measured in s.c. matrigel model was not significant. Changes in leptin concentration were not accompanied by significant angiogenic response. This lack of leptin activity and impaired signal transduction at the molecular level suggests malfunction of the leptin receptor in NZO mice. 相似文献
498.
Tomasz Gortat Michał Kozakiewicz Miłosława Barkowska Urszula Charytonik 《Acta theriologica》2004,49(4):465-477
A field experiment was carried out in two types of forest environment — a relatively homogenous mixed coniferous forest with
low plant species diversity and a reach and spatially differentiated alder wood. Spatial variation in activity of voles was
sampled by placing ink pads and paper inside PVC waterpipes laid in a line on the forest floor. In the first stage of the
experiment, use of space by bank volesClethrionomys glareolus (Schreber, 1780) was analysed without any bait in track collection tubes. In the second stage, we used an attractant in the
form of scent collected from alien bank vole individuals of different sex (males, females), age (juveniles, adults) and physiological
state (sexually active and not active). In the coniferous forest the distribution of number of visits in tracking tubes was
of aggregated character both before and after providing odour of alien individuals. In the alder wood the aggregation level
that had been initially lower than in the coniferous forest increased after providing scent. As a consequence, placing scent
of alien individuals resulted in decreasing differences in animal distribution in both habitats. The results allow also to
the supposition that the reaction to scent depends on sex, age, and the physiological state of the donor. 相似文献
499.
Urszula Kalinowska Magdalena Ma?ecka Bernhard Lippert 《Inorganica chimica acta》2005,358(8):2464-2472
The synthesis of diethyl (pyridin-2-, -3-, -4-ylmethyl)phosphate (2-pmOpe, 3-pmOpe, 4-pmOpe) ligands and their palladium (II) complexes of general formula trans-[PdCl2L2] (L = 2-pmOpe, 3-pmOpe,4-pmOpe) has been described. Pyridine phosphate derivatives were synthesized via the condensation of phosphorochloridic acid diethyl ester with an appropriate pyridinylmethanol in the presence of triethylamine. The compounds have been identified and characterized by IR, far-IR, 1H NMR, 31P NMR, 31P CP-MAS NMR and elemental analyses. The crystal and molecular structures of palladium (II) complexes, i.e., [PdCl2(2-pmOpe)2] and [PdCl2(4-pmOpe)2] determined by the X-ray diffraction method, are presented. In both structures, Pd(II) ions are four-coordinated by two chlorine atoms and two pyridine nitrogen atoms. The geometry of complexes is square-planar and adopt a trans configuration, which is consistent with preparation method. 相似文献
500.
Males (n=34) and females (n=23) of long-tailed duck (Clangula hyemalis) collected on the southern coast of the Baltic Sea in winter were studied to determine brain tissue concentration of iron
(Fe), zinc (Zn), copper (Cu), manganese (Mn), and cadmium (Cd). There were no significant differences in the concentration
of metals between males and females, except for Cd, the concentration of which in male brains was twice that of the females.
In the brains of 20 birds (41% male and 26% female), the lead (Pb) concentration exceeded 1 μg/g wet wt. In all the duck brains
examined, Spearman correlation coefficients were significant and positive for Zn−Mn, Cu−Mn, Cu−Fe, and Pb−Fe; a negative correlation
was found for Pb−Zn. Additionally, female brains showed a positive correlation between Pb and Fe. The results obtained were
compared with literature data for diving and nondiving anseriforms and birds of other taxa. It seems that concentration of
heavy metals in the brain tissue of birds reflect natural adaptations (e.g., for diving) as well as effects of environmental
pollution. 相似文献