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81.
Burioka N Takata M Endo M Miyata M Takeda K Chikumi H Tomita K Fukuoka Y Nakazaki H Sano H Shimizu E 《Chronobiology international》2007,24(1):183-189
This study examined whether in vivo exposure to a β2-adrenoceptor agonist, tulobuterol, induces human Period1 (hPer1) mRNA expression in cells from peripheral whole blood. In one experiment, oral tulobuterol was administered to five healthy volunteers at 22:00 h, while in another, a transdermally tulobuterol patch was applied to the same five subjects at 20:00 h. In each experiment, serum tulobuterol concentrations were measured at four time points, and total RNA was isolated from peripheral blood cells for determinations of hPer1 mRNA expression by real-time polymerase chain reaction. Both the tulobuterol tablet and the transdermal patch increased hPer1 mRNA expression, suggesting that analyses of human peripheral blood cells could reliably represent peripheral clock gene mRNA expression in vivo. 相似文献
82.
Md. Habibur Rahman Tohru Tsuchiya Keita Suwabe Junna Kohori Rubens Norio Tomita Yasuaki Kagaya Issei Kobayashi Katsuyuki Kakeda Yasuo Kowyama 《Sexual plant reproduction》2007,20(2):63-72
Sporophytic self-incompatibility (SSI) in the genus Ipomoea (Convolvulaceae) is controlled by a single polymorphic S locus. We have previously analyzed genomic sequences of an approximately 300 kb region spanning the S locus of the S
1
haplotype and characterized the genomic structure around this locus. Here, we further define the physical size of the S locus region by mapping recombination breakpoints, based on sequence analysis of PCR fragments amplified from the genomic
DNA of recombinants. From the recombination analysis, the S locus of the S
1
haplotype was delimited to a 0.23 cM region of the linkage map, which corresponds to a maximum physical size of 212 kb. To
analyze differences in genomic organization between S haplotypes, fosmid contigs spanning approximately 67 kb of the S
10
haplotype were sequenced. Comparison with the S
1
genomic sequence revealed that the S haplotype-specific divergent regions (SDRs) spanned 50.7 and 34.5 kb in the S
1
and S
10
haplotypes, respectively and that their flanking regions showed a high sequence similarity. In the sequenced region of the
S
10
haplotype, five of the 12 predicted open reading frames (ORFs) were found to be located in the divergent region and showed
co-linear organization of genes between the two S haplotypes. Based on the size of the SDRs, the physical size of the S locus was estimated to fall within the range 34–50 kb in Ipomoea. 相似文献
83.
84.
Jung J Iijima M Yoshimoto N Sasaki M Niimi T Tatematsu K Jeong SY Choi EK Tanizawa K Kuroda S 《Protein expression and purification》2011,78(2):149-155
Bio-nanocapsules (BNCs) are hollow particles (approx. 50 nm diameter) consisting of hepatitis B virus surface antigen (HBsAg) large (L, pre-S1+pre-S2+S) proteins embedded in a unilamellar liposome, sharing the same transmembrane S region with an immunogen of hepatitis B vaccine (i.e., HBsAg small (S) protein particle). BNCs can incorporate drugs and genes into the hollow space and systemic administration of the BNCs can deliver the products to human liver via the human hepatocyte-specific receptor within the pre-S (pre-S1+pre-S2) region displayed on BNC's surface. Thus, BNCs are expected to offer efficient and safe non-viral nanocarriers to deliver human liver-specific genes and drugs. To date, BNCs have been purified from the crude extract of BNC-overexpressing yeast cells by fractionation with polyethylene glycol followed by one CsCl equilibrium and two sucrose density gradient ultracentrifugation steps. However, the process was inefficient in terms of yield and time, and was not suitable for mass production because of the ultracentrifugation step. Furthermore, trace contamination with yeast-derived proteinases degraded the pre-S region, which is indispensable for liver-targeting, during long-term storage. In this study, we developed a new purification method involving heat treatment and sulfated cellulofine column chromatography to facilitate rapid purification, completely remove proteinases, and enable mass production. In addition, the BNCs were functional for at least 14 months after lyophilization with 5% (w/v) sucrose as an excipient. This new process will significantly contribute to the development of forthcoming BNC-based nanomedicines as well as hepatitis B vaccines. 相似文献
85.
Shimizu K Aizawa K Suzuki N Masuchi K Okada H Akimoto T Mesaki N Kono I Akama T 《Journal of strength and conditioning research / National Strength & Conditioning Association》2011,25(7):1943-1950
The purpose of this study was to examine weight loss effects on immune function in judo athletes. Six elite male Japanese judo athletes (20.3 ± 0.4 years) were enrolled in this study. They completed usual weight loss programs during 2 weeks preceding an actual competition. Subjects noted the appearance of upper-respiratory tract infection (URTI) symptoms during the study period. Blood samples were obtained at 40 (baseline period: BL) and 3 (weight loss period: WL) days before and 1 day after the competition (AC). The CD3, CD4, CD8, CD56CD3, CD28CD4, CD28CD8, and Toll-like-receptor-4 (TLR-4) CD14 cells were counted by using flow cytometer analysis. The 6 subjects reported 1 headache, 3 runny nose conditions, and 1 coughing instance during the WL. The CD3, CD4, CD8, and CD28CD4 cell counts were significantly lower at WL than at BL (p ≤ 0.05); they reverted to the baseline value at AC. The TLR-4CD14 cells were significantly fewer at WL (p ≤ 0.05); they remained fewer than they had been at BL, even at AC. These results suggest that 2 weeks of weight loss before a competition can impair cell-mediated immune function and induce high susceptibility to URTI in judo athletes. Coaches, support staff, and athletes should monitor athletes' weight loss, hydration status, appearance of URTI symptoms, and immunocompetence such as lymphocytes and monocytes to prevent the physical condition from becoming worse. 相似文献
86.
87.
Tanabe K Liu Y Hasan SD Martinez SC Cras-Méneur C Welling CM Bernal-Mizrachi E Tanizawa Y Rhodes CJ Zmuda E Hai T Abumrad NA Permutt MA 《PloS one》2011,6(4):e18146
Background
The combination of elevated glucose and free-fatty acids (FFA), prevalent in diabetes, has been suggested to be a major contributor to pancreatic β-cell death. This study examines the synergistic effects of glucose and FFA on β-cell apoptosis and the molecular mechanisms involved. Mouse insulinoma cells and primary islets were treated with palmitate at increasing glucose and effects on apoptosis, endoplasmic reticulum (ER) stress and insulin receptor substrate (IRS) signaling were examined.Principal Findings
Increasing glucose (5–25 mM) with palmitate (400 µM) had synergistic effects on apoptosis. Jun NH2-terminal kinase (JNK) activation peaked at the lowest glucose concentration, in contrast to a progressive reduction in IRS2 protein and impairment of insulin receptor substrate signaling. A synergistic effect was observed on activation of ER stress markers, along with recruitment of SREBP1 to the nucleus. These findings were confirmed in primary islets. The above effects associated with an increase in glycogen synthase kinase 3β (Gsk3β) activity and were reversed along with apoptosis by an adenovirus expressing a kinase dead Gsk3β.Conclusions/Significance
Glucose in the presence of FFA results in synergistic effects on ER stress, impaired insulin receptor substrate signaling and Gsk3β activation. The data support the importance of controlling both hyperglycemia and hyperlipidemia in the management of Type 2 diabetes, and identify pancreatic islet β-cell Gsk3β as a potential therapeutic target. 相似文献88.
89.
Euphorbia tirucalli L., known as the petroleum plant, produces a large amount of triterpenes, such as beta-amyrin. Degenerate RT-PCR based on the sequences conserved among known beta-amyrin synthases led to cloning of a putative triterpene synthase cDNA, EtAS, from leaves of E. tirucalli. The deduced amino acid sequence of the EtAS cDNA showed the highest identity of 82% to the Panax ginseng beta-amyrin synthase. Heterologous expression of the EtAS ORF in the methylotrophic yeast, Pichia pastoris, resulted in production of beta-amyrin, revealing that the EtAS cDNA codes for a beta-amyrin synthase. This is the first report of a gene involved in the triterpene synthetic pathway from Euphorbiaceae plants. 相似文献
90.
KIT (c-kit oncogene product) pathway is constitutively activated in human testicular germ cell tumors 总被引:5,自引:0,他引:5
Nakai Y Nonomura N Oka D Shiba M Arai Y Nakayama M Inoue H Nishimura K Aozasa K Mizutani Y Miki T Okuyama A 《Biochemical and biophysical research communications》2005,337(1):289-296
We investigated the expression of KIT (product of c-kit oncogene), gain-of-function mutations, and activation of its downstream signal transduction in human testicular cancers. KIT was expressed in 88% (22/25) of seminomas and in 44.4% (4/9) of non-seminomas compared to adjacent normal testicular tissue. Nine of the KIT-expressing seminomas had mutations (40.9%; 9/22) in the c-kit gene; two cases in exon 11 and 7 cases in exon 17. Two of these mutations in exon 17 were novel, and the other seven mutations were identical to the already known gain-of-function mutations which cause activation of KIT without ligand stem cell factor. All of the mutant KIT and 53.8% (7/13) of wild-type KIT were phosphorylated (activated) and associated with phosphorylated phosphatidylinositol 3-kinase (PI3K). Akt was also phosphorylated in these seminomas, suggesting that the KIT-PI3K-Akt pathway is activated in seminoma. These findings suggest that the KIT-PI3K-Akt pathway is constitutively activated in testicular germ cell tumors, due to overexpression of KIT protein and/or gain-of-function mutations in the c-kit gene. 相似文献