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991.
The effects of MD-Fraction, a β-glucan extracted from Maitake mushroom (Grifola frondosa), on the health status of individuals suffering from HIV infection were evaluated in a long-term trial. The HIV status of
the 35 respondents who participated in the study was followed by monitoring CD4+ cell counts, viral load measure, symptoms of HIV infection, status of secondary disease, and sense of well-being. Twenty
patients reported an increase in CD4+ cell counts to 1.4–1.8 times, and 8 patients reported a decrease to 0.8–0.5 times. Viral load was reported to increase in
9 patients and decrease in 10 patients. However, 85% of respondents reported an increased sense of well-being with regard
to various symptoms and secondary diseases caused by HIV. These results suggest that Maitake D-Fraction had a positive impact
in HIV patients. 相似文献
992.
993.
994.
Kota Saito Koh Yamashiro Noriko Shimazu Tomoya Tanabe Kenji Kontani Toshiaki Katada 《The Journal of cell biology》2014,206(6):751-762
Mechanisms for exporting variably sized cargo from the endoplasmic reticulum (ER) using the same machinery remain poorly understood. COPII-coated vesicles, which transport secretory proteins from the ER to the Golgi apparatus, are typically 60–90 nm in diameter. However, collagen, which forms a trimeric structure that is too large to be accommodated by conventional transport vesicles, is also known to be secreted via a COPII-dependent process. In this paper, we show that Sec12, a guanine-nucleotide exchange factor for Sar1 guanosine triphosphatase, is concentrated at ER exit sites and that this concentration of Sec12 is specifically required for the secretion of collagen VII but not other proteins. Furthermore, Sec12 recruitment to ER exit sites is organized by its direct interaction with cTAGE5, a previously characterized collagen cargo receptor component, which functions together with TANGO1 at ER exit sites. These findings suggest that the export of large cargo requires high levels of guanosine triphosphate–bound Sar1 generated by Sec12 localized at ER exit sites. 相似文献
995.
Yoshikazu Hasegawa Yoko Daitoku Seiya Mizuno Yoko Tanimoto Saori Mizuno-Iijima Miki Matsuo Noriko Kajiwara Masatsugu Ema Hisashi Oishi Yoshihiro Miwa Kazuyuki Mekada Atsushi Yoshiki Satoru Takahashi Fumihiro Sugiyama Ken-ichi Yagami 《Experimental Animals》2014,63(2):183-191
Cre/loxP system-mediated site-specific recombination is utilized to study gene function
in vivo. Successful conditional knockout of genes of interest is
dependent on the availability of Cre-driver mice. We produced and characterized pancreatic
β cell-specific Cre-driver mice for use in diabetes mellitus research. The gene encoding
Cre was inserted into the second exon of mouse Ins1 in a bacterial
artificial chromosome (BAC). Five founder mice were produced by microinjection of
linearized BAC Ins1-cre. The transgene was integrated between
Mafa and the telomere on chromosome 15 in one of the founders, BAC
Ins1-cre25. To investigate Cre-loxP recombination, BAC Ins1-cre25 males were crossed with
two different Cre-reporters, R26R and R26GRR females. On gross observation, reporter
signal after Cre-loxP recombination was detected exclusively in the adult pancreatic
islets in both F1 mice. Immunohistological analysis indicated that Cre-loxP
recombination-mediated reporter signal was colocalized with insulin in pancreatic islet
cells of both F1 mice, but not with glucagon. Moreover, Cre-loxP recombination
signal was already observed in the pancreatic islets at E13.5 in both F1
fetuses. Finally, we investigated ectopic Cre-loxP recombination for
Ins1, because the ortholog Ins2 is also expressed in the
brain, in addition to the pancreas. However, there was no Cre-loxP recombination-mediated
reporter signal in the brain of both F1 mice. Our data suggest that BAC
Ins1-cre25 mice are a useful Cre-driver C57BL/6N for pancreatic β cell-specific Cre-loxP
recombination, except for crossing with knock-in mice carrying floxed gene on chromosome
15. 相似文献
996.
Noriko Fukushima 《Biochemical and biophysical research communications》2009,383(2):231-234
(6-4) photolyase repairs pyrimidine-pyrimidone (6-4) photoproducts generated in DNA upon UV light exposure. We studied the effects of blue light on the expression of this gene in Xenopus A6 cells. Exposure of the cells to blue light, but not red light, for 12 h resulted in more than 20-fold increase of the (6-4) photolyase mRNA. By contrast, levels of the other two photolyase mRNAs, i.e., those for CPD photolyase and cryptochrome DASH, did not change significantly. Oxygen radicals presumably generated within the cells upon exposure to blue light were not the cause of the induction, since addition of neither hydrogen peroxide nor a photosensitizer, phenol red, in the culture medium increased the (6-4) photolyase mRNA level. These results support the possibility that the expression of (6-4) photolyase may be regulated by a mechanism involving an as yet ill-defined blue light photoreceptor in the peripheral tissues of Xenopus. 相似文献
997.
998.
The wood mouse Apodemus speciosus can consume the hard-walled walnut species Juglans ailanthifolia. The mice gnaw holes on two sides of the shell and then pick the meat from the holes. However, not all mice are able to eat
these walnuts, because the shells are extremely hard and the process is labour-intensive. To consume all of the meat it is
more efficient to eat from holes on the raphe than to attempt to eat from other parts of the shell. We examined the effect
of experience on the walnut-feeding skills of mice in the field. Feeding behaviours were compared among mice from habitats
with and without walnut trees. Mice from habitats with walnut trees tended to consume nuts more efficiently than mice from
habitats without walnut trees. We also observed the feeding behaviour of mice in an experimental area into which walnuts were
artificially placed over a period of one year. This manipulation increased the proportion of mice that were able to eat nuts
frequently and efficiently. Therefore, the walnut-feeding skills of mice improved with experience. Because individual mice
acquired efficient feeding during the 14-day period of walnut conditioning, trial-and-error learning may be an important mechanism
contributing to this behaviour. 相似文献
999.
An unusual lanostane-type triterpenoid, spiroinonotsuoxodiol (1), and two lanostane-type triterpenoids, inonotsudiol A (2) and inonotsuoxodiol A (3), were isolated from the sclerotia of Inonotus obliquus. Their structures were determined to be (3S,7S,9R)-3,7-dihydroxy-7(8 → 9)abeo-lanost-24-en-8-one (1), lanosta-8,24-dien-3β,11β-diol (2), and (22R)-3β,22-dihydroxylanosta-8,24-dien-11-one (3) on the basis of NMR spectroscopy, including 1D and 2D (1H–1H COSY, NOESY, HMQC, HMBC) NMR, and FABMS. Compounds 1–3 showed moderate activity against cultured P388, L1210, HL-60 and KB cells. 相似文献
1000.
Lee WH Akatsuka S Shirase T Dutta KK Jiang L Liu YT Onuki J Yamada Y Okawa K Wada Y Watanabe A Kohro T Noguchi N Toyokuni S 《Archives of biochemistry and biophysics》2006,453(2):168-178
Pre-administration of alpha-tocopherol is protective against oxidative renal tubular damage and subsequent carcinogenesis by ferric nitrilotriacetate (Fe-NTA) in rats. We searched for mechanisms other than the scavenging effect of alpha-tocopherol with microarray analyses, which implicated calnexin, a chaperone for glycoproteins. Renal mRNA levels of calnexin significantly increased 3h after an injection of Fe-NTA in rats fed a standard diet whereas those fed an alpha-tocopherol-supplemented diet showed an increase prior to injection, but after injection showed a decrease in renal calnexin mRNA levels, with unaltered protein levels. In experiments using LLC-PK1 cells, addition of alpha-tocopherol was protective against oxidative stress by H2O2, concomitant with calnexin induction. Knockdown of calnexin by siRNA significantly reduced this protection. Furthermore, COS-7 cells transfected with the calnexin gene were more resistant to H2O2. Together with the fact that alpha-tocopherol induced N-acetylglucosaminyltransferase 3, our data suggest that alpha-tocopherol modifies glycoprotein metabolism partially by conferring mild ER stress. This adds another molecular mechanism of alpha-tocopherol toward cancer prevention. 相似文献