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961.
Satoru Tamura Gang-Ming Yang Natsuko Yasueda Yoshiharu Matsuura Yasumasa Komoda Nobutoshi Murakami 《Bioorganic & medicinal chemistry letters》2010,20(5):1598-1600
By use of the model virus, expressing the HCV envelope proteins E1 and E2, bioassay guided separation of the MeOH extract from Rosa rugosa Thunb. disclosed tellimagrandin I (1) together with eugeniin (2) and casuarictin (3) as the potent HCV invasion inhibitors. Furthermore, structure–activity relationship analysis of some relative tannins including the synthesized analogs elucidated the partial structures crucial for potent activity of 1. 相似文献
962.
The posttranslational processing of ras p21 is critical for its stimulation of yeast adenylate cyclase. 下载免费PDF全文
H Horiuchi K Kaibuchi M Kawamura Y Matsuura N Suzuki Y Kuroda T Kataoka Y Takai 《Molecular and cellular biology》1992,12(10):4515-4520
Mammalian ras genes substitute for the yeast RAS gene, and their products activate adenylate cyclase in yeast cells, although the direct target protein of mammalian ras p21s remains to be identified. ras p21s undergo posttranslational processing, including prenylation, proteolysis, methylation, and palmitoylation, at their C-terminal regions. We have previously reported that the posttranslational processing of Ki-ras p21 is essential for its interaction with one of its GDP/GTP exchange proteins named smg GDS. In this investigation, we have studied whether the posttranslational processing of Ki- and Ha-ras p21s is critical for their stimulation of yeast adenylate cyclase in a cell-free system. We show that the posttranslationally fully processed Ki- and Ha-ras p21s activate yeast adenylate cyclase far more effectively than do the unprocessed proteins. The previous and present results suggest that the posttranslational processing of ras p21s is important for their interaction not only with smg GDS but also with the target protein. 相似文献
963.
Masaaki Matsuura Pranee Somboonthum Kouki Murakami Megumi Ota Masaki Shoji Kenji Kawabata Hiroyuki Mizuguchi Yasuyuki Gomi Koichi Yamanishi Yasuko Mori 《Microbiology and immunology》2013,57(10):704-714
The varicella–zoster virus (VZV) Oka vaccine strain (vOka) is a highly immunogenic and safe live vaccine that has long been used worldwide. Because its genome is large, making it suitable for inserting foreign genes, vOka is considered a candidate vector for novel polyvalent vaccines. Previously, a recombinant vOka, rvOka‐HN, that expresses mumps virus (MuV) hemagglutinin‐neuraminidase (HN) was generated by the present team. rvOka‐HN induces production of neutralizing antibodies against MuV in guinea pigs. MuV also expresses fusion (F) protein, which is important for inducing neutralizing antibodies, in its viral envelope. To induce a more robust immune response against MuV than that obtained with rvOka‐HN, here an rvOka expressing both HN and F (rvOka‐HN‐F) was generated. However, co‐expression of HN and F caused the infected cells to form syncytia, which reduced virus titers. To reduce the amount of cell fusion, an rvOka expressing HN and a mutant F, F(S195Y) were generated. Almost no syncytia formed among the rvOka‐HN‐F(S195Y)‐infected cells and the growth of rvOka‐HN‐F(S195Y) was similar to that of the original vOka clone. Moreover, replacement of serine 195 with tyrosine had no effect on the immunogenicity of F in mice and guinea pigs. Although obvious augmentation of neutralizing antibody production was not observed after adding F protein to vOka‐HN, the anti‐F antibodies did have neutralizing activity. These data suggest that F protein contributes to induction of immune protection against MuV. Therefore this recombinant virus is a promising candidate vaccine for polyvalent protection against both VZV and MuV. 相似文献
964.
K Matsuura A Hara H Sawada Y Bunai I Ohya 《The journal of histochemistry and cytochemistry》1990,38(2):217-223
We studied the localization of carbonyl reductase (E.C. 1.1.1.184) in guinea pig and mouse lung by enzyme histochemistry and immunohistochemistry, using antibodies against the guinea pig lung enzyme which crossreacted with the lung enzymes of both animals. Carbonyl reductase activity was detectable in the bronchiolar epithelial cells of small airways and in alveolar cells. In the immunohistochemical staining for carbonyl reductase, the reaction was strongest in the non-ciliated bronchiolar cells (Clara cells) and was weak in the ciliated cells and type II alveolar pneumocytes. Injection of a single dose of naphthalene led to significant impairment of carbonyl reductase activity and of microsomal mixed-function oxidase activities in mouse lung, with a marked decrease in both activity and immunoreactive staining in the bronchiolar epithelial cells. The results indicate that carbonyl reductase is localized primarily in the Clara cells, which are known to be sites of pulmonary drug metabolism. 相似文献
965.
Ether phospholipid molecular species in human platelets 总被引:2,自引:0,他引:2
Molecular species of diacyl, alkenylacyl, and alkylacyl subclasses in human platelet phospholipids were quantitatively analyzed. Dinitrobenzoyldiradylglycerol derivatives prepared from phosphatidylcholine and phosphatidylethanolamine were separated into subclasses by TLC or normal-phase HPLC. Each subclass consisting of more than 20 molecular species was quantified by reverse-phase HPLC with the eluting solvent of acetonitrile-2-propanol (80 : 20). The retention times of molecular species in the alkenylacyl and alkylacyl subclasses were approximately 1.24 and 1.56 times as long as that of the diacyl type. Phosphatidylcholine contained mostly diacyl subclass (94.5%) and small amounts of alkenylacyl (0.8%) and alkylacyl (4.7%) subclasses, while phosphatidylethanolamine was comprised of 44.2% diacyl, 54.4% alkenylacyl, and 1.4% alkylacyl subclasses. The diacyl subclass of phosphatidylcholine mainly consisted of monoenoic and dienoic molecular species, whereas the other subclasses of phosphatidylcholine and all subclasses of phosphatidylethanolamine were mostly comprised of polyenoic molecular species. The distribution of arachidonic acid-containing molecular species in the diacyl, alkenylacyl, and alkylacyl subclasses were 18.7, 48.2, and 47.9%, respectively, in phosphatidylcholine, and 60.1, 63.0, and 46.9% in phosphatidylethanolamine. Hence, the alkylacyl and alkenylacyl subclasses of phosphatidylcholine seem to play physiological roles different from the diacyl subclass in human platelets. 相似文献
966.
S Ando K Kaibuchi T Sasaki K Hiraoka T Nishiyama T Mizuno M Asada H Nunoi I Matsuda Y Matsuura 《The Journal of biological chemistry》1992,267(36):25709-25713
rac1 and rac2 p21s are ras p21-like small GTP-binding proteins which are implicated in the NADPH oxidase-catalyzed superoxide generation in phagocytes. rac1 and rac2 p21s have a Cys-A-A-Leu (A = aliphatic amino acid) structure in their C-terminal region which may undergo post-translational processing including prenylation, proteolysis, and carboxyl methylation. We studied the function of this post-translational processing of rac p21s in their interaction with the stimulatory and inhibitory GDP/GTP exchange proteins for rac p21s, named smg GDS and rho GDI, and in their NADPH oxidase activation. We produced human recombinant rac1 and rac2 p21s in insect cells and purified them from the membrane and soluble fractions as the post-translationally processed and unprocessed forms, respectively. Post-translationally processed rac1 and rac2 p21s were sensitive to both smg GDS and rho GDI, but post-translationally unprocessed rac1 and rac2 p21s were insensitive to them. The GTP gamma S (guanosine 5'-(3-O-thio)triphosphate)-bound form of post-translationally processed rac1 and rac2 p21s stimulated the NADPH oxidase activity, but post-translationally unprocessed rac1 and rac2 p21s were far less effective. These results indicate that both rac1 and rac2 p21s stimulate the NADPH oxidase activity and that their post-translational processing is important not only for their interaction with smg GDS and rho GDI but also for their NADPH oxidase activation. 相似文献
967.
Niwa J Ishigaki S Hishikawa N Yamamoto M Doyu M Murata S Tanaka K Taniguchi N Sobue G 《The Journal of biological chemistry》2002,277(39):36793-36798
Amyotrophic lateral sclerosis (ALS) is a progressive paralytic disorder resulting from the degeneration of motor neurons in the cerebral cortex, brainstem, and spinal cord. The cytopathological hallmark in the remaining motor neurons of ALS is the presence of ubiquitylated inclusions consisting of insoluble protein aggregates. In this paper we report that Dorfin, a RING finger-type E3 ubiquitin ligase, is predominantly localized in the inclusion bodies of familial ALS with a copper/zinc superoxide dismutase (SOD1) mutation as well as sporadic ALS. Dorfin physically bound and ubiquitylated various SOD1 mutants derived from familial ALS patients and enhanced their degradation, but it had no effect on the stability of the wild-type SOD1. The overexpression of Dorfin protected against the toxic effects of mutant SOD1 on neural cells and reduced SOD1 inclusions. Our results indicate that Dorfin protects neurons by recognizing and then ubiquitylating mutant SOD1 proteins followed by targeting them for proteasomal degradation. 相似文献
968.
Shinsuke Morioka Kosuke Sano Phoutsamone Phommachan Bounsong Vongvichith 《Ichthyological Research》2010,57(2):139-147
The morphological development, including the fins, body proportions and pigmentation, of laboratory-reared larval and juvenile
Pangasianodon hypophthalmus was described and their behavioral features were observed under rearing conditions. Body lengths (BL) of larvae and juveniles
were 3.0 ± 0.2 (mean ± SD) mm just after hatching, and 12.9 ± 1.1 mm on day 13, reaching 23.4 ± 1.8 mm on day 25 after hatching.
Aggregate fin ray numbers (for caudal fin, principal soft ray number) attained their full complements in specimens larger
than 12.8 mm BL. Notochord flexion began in yolksac larvae on day 0 (10.5 h after hatching), with teeth buds and barbels appearing
with jaw formation in yolksac flexion larvae on day 1. Melanophores on the body increased with growth, with a broad vertical
band forming on the lateral line and an oblique band extending from above the pectoral fin base towards the forepart of the
anal fin during the postflexion larval and juvenile stages. Body proportions became relatively constant in juveniles, except
for maxillary barbel length (MBL), which continued to decrease. Yolksac flexion larvae started feeding on day 2 with the onset
of intense cannibalism. Yolks were completely absorbed by day 3, and cannibalism ended by day 6. Subsequently, fish displayed
a schooling behavior with growth, preferring relatively dark areas during the juvenile stage. 相似文献
969.
Nawarat Posuwan Sunchai Payungporn Pisit Tangkijvanich Shintaro Ogawa Shuko Murakami Sayuki Iijima Kentaro Matsuura Noboru Shinkai Tsunamasa Watanabe Yong Poovorawan Yasuhito Tanaka 《PloS one》2014,9(1)
Background
Previous studies showed that single nucleotide polymorphisms (SNPs) in the HLA-DP, TCF19 and EHMT2 genes may affect the chronic hepatitis B (CHB). To predict the degree of risk for chronicity of HBV, this study determined associations with these SNPs.Methods
The participants for this study were defined into 4 groups; HCC (n = 230), CHB (n = 219), resolved HBV infection (n = 113) and HBV uninfected subjects (n = 123). The HLA-DP SNPs (rs3077, rs9277378 and rs3128917), TCF19 SNP (rs1419881) and EHMT2 SNP (rs652888) were genotyped.Results
Due to similar distribution of genotype frequencies in HCC and CHB, we combined these two groups (HBV carriers). The genotype distribution in HBV carriers relative to those who resolved HBV showed that rs3077 and rs9277378 were significantly associated with protective effects against CHB in minor dominant model (OR = 0.45, p<0.001 and OR = 0.47, p<0.001). The other SNPs rs3128917, rs1419881 and rs652888 were not associated with HBV carriers.Conclusions
Genetic variations of rs3077 and rs9277378, but not rs3128917, rs1419881 and rs652888, were significantly associated with HBV carriers relative to resolved HBV in Thai population. 相似文献970.
Shugo Tohyama Fumiyuki Hattori Motoaki Sano Takako Hishiki Yoshiko Nagahata Tomomi Matsuura Hisayuki Hashimoto Tomoyuki Suzuki Hiromi Yamashita Yusuke Satoh Toru Egashira Tomohisa Seki Naoto Muraoka Hiroyuki Yamakawa Yasuyuki Ohgino Tomofumi Tanaka Masatoshi Yoichi Shinsuke Yuasa Keiichi Fukuda 《Cell Stem Cell》2013,12(1):127-137
Highlights? Integrated “omic” analyses reveal metabolic hallmarks in ESCs and cardiomyocytes ? Glucose depletion and lactate supplementation can purify PSC-derived cardiomyocytes ? Cardiomyocytes can use lactate efficiently for energy metabolism ? Transplanted purified human ESC-derived cardiomyocytes do not form tumors 相似文献