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41.
42.
Takeshi Urao Takeshi Katagiri Tsuyoshi Mizoguchi Kazuko Yamaguchi-Shinozaki Nobuaki Hayashida Kazuo Shinozaki 《Molecular genetics and genomics : MGG》1994,244(4):331-340
Two cDNA clones, AATCDPK1 and cATCDPK2, encoding Ca2+-dependent, calmodulin-independent protein kinases (CDPK) were cloned from Arabidopsis thaliana and their nucleotide sequences were determined. Northern blot analysis indicated that the mRNAs corresponding to the ATCDPK1 and ATCDPK2 genes are rapidly induced by drought and high-salt stress but not by low-temperature stress or heat stress. Treatment of Arabidopsis plants with exogenous abscisic acid (ABA) had no effect on the induction of ATCDPK1 or ATCDPK2. These findings suggest that a change in the osmotic potential of the environment can serve as a trigger for the induction of ATCDPK1 and ATCDPK2. Putative proteins encoded by ATCDPK1 and ATCDPK2 which contain open reading frames of 1479 and 1488 bp, respectively, are designated ATCDPK1 and ATCDPK2 and show 52% identity at the amino acid sequence level. ATCDPK1 and ATCDPK2 exhibit significant similarity to a soybean CDPK (51 % and 73%, respectively). Both proteins contain a catalytic domain that is typical of serine/threonine protein kinases and a regulatory domain that is homologous to the Ca2+-binding sites of calmodulin. Genomic Southern blot analysis suggests the existence of a few additional genes that are related to ATCDPK1 and ATCDPK2 in the Arabidopsis genome. The ATCDPK2 protein expressed in Escherichia coli was found to phosphorylate casein and myelin basic protein preferentially, relative to a histone substrate, and required Ca2+ for activation. 相似文献
43.
44.
Kazuko Wada Shintaro Nomura Eiichi Morii Yukihiko Kitamura Yasuko Nishizawa Akira Miyake Nobuyuki Terada 《The Journal of steroid biochemistry and molecular biology》1996,59(5-6):367-375
To examine the roles played by transforming growth factors (TGF)-β1, -β2, -β3, and TGF-β type II receptors in the induction of apoptosis in the mouse uterine epithelium after estrogen deprivation, we investigated the expression of their mRNAs and the mRNA of sulfated glycoprotein-2 (SGP-2). Pellets containing 100 μg estradiol-17β (E2) were implanted into ovariectomized mice and removed four days later. Apoptotic indices (percentage of apoptotic cells) of both luminal and glandular epithelia increased after E2 pellets were removed, but administration of progesterone (P), 5-dihydrotestosterone (DHT), or continued implantation of E2 pellets suppressed this increase. Levels of mRNAs of TGF-β1, -β2, and -β3, and SGP-2 did not increase after estrogen deprivation. However, estrogen deprivation caused a gradual increase in the level of TGF-β type II receptor mRNA, and its level increased about six-fold six days later. Moreover, E2, P, and DHT markedly decreased the level of TGF-β type II receptor mRNA. In situ hybridization demonstrated that mRNAs of TGF-β1, -β2, -β3 and TGF-β type II receptor were localized to the epithelium. Exogenous administration of TGF-β1 into the uterine stroma induced apoptosis in the epithelium, a finding that suggests that signals produced by TGF-βs can induce apoptosis. Therefore, the present results suggest that increased sensitivity of uterine epithelial cells to TGF-βs, as demonstrated by an increase in TGF-β type II receptor mRNA, is involved in the induction of apoptosis after estrogen deprivation, although signals produced by TGF-βs do not appear sufficient to induce apoptosis. 相似文献
45.
SGLT1, an isoform of Na+-dependent glucose transporters, is localized at the apical plasma membrane in the epithelial cells of the small intestine
and the kidney. In the present study we examined its location in SGLT1 cDNA-transfected MDCK cells, which form an epithelial
sheet connected by tight junctions in culture. Formation of tight junctions was monitored by staining for occludin, an integral
tight junction protein. In the cells demarcated by an uninterrupted occludin meshwork, SGLT1 was specifically localized at
the apical plasma membrane, showing that SGLT1 has a signal to accomplish this restricted localization. In the cells with
little or no occludin accumulation in the tight junction, however, SGLT1 was present along the entire aspect of the plasma
membrane. Similar distribution of SGLT1 was observed in the cells as long as the occludin meshwork remained incomplete. These
observations sugget that apical localization of SGLT1 occurs upon the completion of the uninterrupted meshwork of tight junctions. 相似文献
46.
Yoshikazu Horie Toshimitu Fukiharu Kazuko Nishimura Hideaki Taguchi Duan Li Wang Ruoyu Li 《Mycoscience》1996,37(3):323-329
Emericella miyajii, a new species isolated from Chinese soil, is described and illustrated. It is characterized by pale orange to brownish orange
colonies on malt extract agar, subglobose to broadly elliptical ascospores with defective four equatorial crests and smooth
convex walls, and with anAspergillus anamorph.Emericella undulata is also described as an uncommon species from Chinese soil. 相似文献
47.
48.
Akihiro Yoshida Kuniaki Takata Toshiko Kasahara Toshio Aoyagi Shozo Saito Hiroshi Hirano 《The Histochemical journal》1995,27(5):420-426
Summary Glucose is actively absorbed in the intestine by the action of the Na+-dependent glucose transporter. Using an antibody against the rabbit intestinal Na+-dependent glucose transporter (SGLT1), we examined the localization of SGLT1 immunohistochemically along the rat digestive
tract (oesophagus, stomach, duodenum, jejunum, ileum, colon and rectum). SGLT1 was detected in the small intestine (duodenum,
jejunum and ileum), but not in the oesophagus, stomach, colon or rectum. SGLT1 was localized at the brush border of the absorptive
epithelium cells in the small intestine. Electron microscopical examination showed that SGLT1 was localized at the apical
plasma membrane of the absorptive epithelial cells. SGLT1 was not detected at the basolateral plasma membrane. Along the crypt-villus
axis, all the absorptive epithelial cells in the villus were positive for SGLT1, whose amount increased from the bottom of
the villus to its tip. On the other hand, cells in the crypts exhibited little or no staining for SGLT1. Goblet cells scattered
throughout the intestinal epithelium were negative for SGLT1. These observations show that SGLT1 is specific to the apical
plasma membrane of differentiated absorptive epithelial cells in the small intestine, and suggest that active uptake of glucose
occurs mainly in the absorptive epithelial cells in the small intestine. 相似文献
49.
Virulent and avirulent Rhodococcus equi infection in T-cell deficient athymic nude mice: pathologic, bacteriologic and immunologic responses 总被引:1,自引:0,他引:1
50.
Characterization of a gene cluster for glycogen biosynthesis and a heterotetrameric ADP-glucose pyrophosphorylase from Bacillus stearothermophilus. 下载免费PDF全文
A chromosomal region of Bacillus stearothermophilus TRBE14 which contains genes for glycogen synthesis was cloned and sequenced. This region includes five open reading frames (glgBCDAP). It has already been demonstrated that glgB encodes branching enzyme (EC 2.4.1.18 [H. Takata et al., Appl. Environ. Microbiol. 60:3096-3104, 1994]). The putative GlgC (387 amino acids [aa]) and GlgD (343 aa) proteins are homologous to bacterial ADP-glucose pyrophosphorylase (AGP [EC 2.7.7.27]): the sequences share 42 to 70% and 20 to 30% identities with AGP, respectively. Purification of GlgC and GlgD indicated that AGP is an alpha2beta2-type heterotetrameric enzyme consisting of these two proteins. AGP did not seem to be an allosteric enzyme, although the activities of most bacterial AGPs are known to be allosterically controlled. GlgC protein had AGP activity without GlgD protein, but its activity was lower than that of the heterotetrameric enzyme. The GlgA (485 aa) and GlgP (798 aa) proteins were shown to be glycogen synthase (EC 2.4.1.21) and glycogen phosphorylase (EC 2.4.1.1), respectively. We constructed plasmids harboring these five genes (glgBCDAP) and assayed glycogen production by a strain carrying each of the derivative plasmids on which the genes were mutated one by one. Glycogen metabolism in B. stearothermophilus is discussed on the basis of these results. 相似文献