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61.
Sridhar Vaddi Venkatesan Thiruvengadam Sunil Joshi Sushil Kumar Jalali Lakshmana Reddy Dhoranalapalli Chinnappareddy Padma Nimmakayala Yan Tomason Gopinath Vajja Umesh K. Reddy 《Entomologia Experimentalis et Applicata》2016,160(2):179-187
Nearly 5 000 aphid species damage crops, either by sucking plant sap or as disease‐transmitting vectors. Microsatellites are used for understanding molecular diversity and eco‐geographical relationships among aphid species. Expressed sequence tag (EST)‐microsatellite motifs were identified through an in silico approach using inbuilt simple sequence repeat mining tools in aphid EST dataset. Microsatellite mining revealed one in every five aphid genes as containing a repeat motif, and out of 9 290 EST microsatellites mined from Aphis gossypii Glover and Acyrthosiphon pisum (Harris) (both Hemiptera: Aphididae), 80% were of A and/or T (AT, ATA, AAT, AATA, and ATTT) motifs, and the rest contained G and/or C motifs. All microsatellite sequences were annotated using BLAST. Primers for EST microsatellites were designed using the Primer 3.0 tool. 106 primer pairs of both dinucleotide repeats (DNRs) and trinucleotide repeats (TNRs), representing open reading frames (ORFs) and untranslated regions (UTRs), were synthesized to amplify 15 aphid species belonging to the subfamily Aphidinae, collected from diverse hosts. Four hundred forty‐five polymorphic alleles were amplified. Fifty TNR and 23 DNR microsatellites amplified across the species studied. Polymorphism information content values of microsatellites ranged from 0.23 to 0.91, amplifying 2–16 alleles. Genetic similarity indices were estimated using the ‘NTSYS‐pc’ software package. Unweighted pair group with arithmetic mean and principal component analysis resolved taxonomic relationships of the aphid species studied. The new aphid microsatellites developed will provide valuable information to researchers to study Indian aphid species diversity and genetic relationships. 相似文献
62.
Mosley CA Taupenot L Biswas N Taulane JP Olson NH Vaingankar SM Wen G Schork NJ Ziegler MG Mahata SK O'Connor DT 《Biochemistry》2007,46(38):10999-11012
The secretory pro-hormone chromogranin A (CHGA) is densely packed into storage granules along with catecholamines, playing a catalytic role in granule biogenesis. 3-Dimensional structural data on CHGA are lacking. We found a superfamily structural homology for CHGA in the tropomyosin family of alpha-helical coiled-coils, even in mid-molecule regions where primary sequence identity is only modest. The assignment was confirmed by an independent algorithm, suggesting approximately 6-7 such domains spanning CHGA. We provide additional physiochemical evidence (chromatographic, spectral, microscopic) consistent with this unusual structure. Alpha-helical secondary structure (at up to approximately 45%) was confirmed by circular dichroism. CHGA molecular mass was estimated by MALDI-TOF mass spectrometry at approximately 50 kDa and by denaturing gel filtration at approximately 50-61 kDa, while its native Stokes radius was approximately 84.8 A, as compared to an expected approximately 30 A; the increase gave rise to an apparent native molecular weight of approximately 578 kDa, also consistent with the extended conformation of a coiled-coil. Small-angle X-ray scattering (SAXS) on CHGA in solution best fit an elongated cylindrical conformation in the monodisperse region with a radius of gyration of the rod cross-section (Rt) of approximately 52 A, compatible with a coiled-coil in the hydrated, aqueous state, or a multimeric coiled-coil. Electron microscopy with negative staining revealed an extended, filamentous CHGA structure with a diameter of approximately 94 +/- 4.5 A. Extended, coiled-coil conformation is likely to permit protein "packing" in the secretory granule at approximately 50% higher density than a globular/spherical conformation. Natural allelic variation in the catestatin region was predicted to disrupt the coiled-coil. Chromaffin granule ultrastructure revealed a approximately 108 +/- 6.3 A periodicity of electron density, suggesting nucleation of a binding complex by the CHGA core. Inhibition of CHGA expression, by siRNA, disrupted regulated secretory protein traffic by approximately 65%, while targeted ablation of the CHGA gene in the mouse reduced chromaffin granule cotransmitter concentrations by approximately 40-80%. These results suggest new roles for secretory protein tertiary structure in hormone and transmitter storage, with implications for secretory cargo condensation (or dense core "packing" structure) within the regulated pathway. 相似文献
63.
The berries of the plant Anamirta cocculus afforded picrotin, picrotoxinin, methyl picrotoxate and two new sesquiterpene γ-lactones, dihydroxypicrotoxinin and picrotoxic acid, whose structures were determined by spectroscopic methods. 相似文献
64.
This article develops dose-response models for Lassa fever virus using data sets found in the open literature. Dose-response data were drawn from two studies in which guinea pigs were given subcutaneous and aerosol exposure to Lassa virus. In one study, six groups of inbred guinea pigs were inoculated subcutaneously with doses of Lassa virus and five groups of out-bred guinea pigs were similarly treated. We found that the out-bred subcutaneously exposed guinea pig did not exhibit a dose-dependent trend in response. The inbred guinea pigs data were best fit by an exponential dose-response model. In a second study, four groups of out-bred guinea pigs were exposed to doses of Lassa virus via the aerosol route. In that study, aerosol diameter was less than 4.5 μ m and both mortality and morbidity were used as endpoints. The log-probit dose-response model provided a somewhat better fit than the Beta-Poisson model for data with mortality as the endpoint, but the Beta-Poisson is considered the best fit model because it can be derived using biological considerations. Morbidity data were best fit with an exponential dose-response model. 相似文献
65.
Wang X Santin AD Bellone S Gupta S Nakagawa M 《Cancer immunology, immunotherapy : CII》2009,58(2):309-308
Previously, safety and immunogenicity of human papillomavirus type 16 (HPV16) or 18 E7-pulsed dendritic cells (DC) vaccinations
were demonstrated in a dose-escalation Phase I clinical trial which enrolled ten patients diagnosed with stage IB or IIA cervical
cancer (nine HPV 16-positive, one HPV 18-positive). The goal of the study was to define the T-cell epitopes of HPV 16 or 18
E7 protein in these patients in order to develop new strategies for treating HPV-associated malignancies. This was accomplished
through establishing T-cell lines by stimulating peripheral blood mononuclear cells with autologous mature DC pulsed with
the HPV 16 or 18 E7 protein, examining the T-cell responses using ELISPOT assays, and isolating E7-specific T-cell clones
based on IFN-γ secretion. Then, the epitope was characterized in terms of its core sequence and the restriction element. Twelve
T-cell lines from eight subjects (seven HPV 16-positive, one HPV 18-positive) were evaluated. Positive T-cell responses were
demonstrated in four subjects (all HPV 16-positive). All four were positive for the HPV 16 E7 46-70 (EPDRAHYNIVTFCCKCDSTLRLCVQ)
region. T-cell clones specific for the E7 47–70 region were isolated from one of the subjects. Further analyses revealed a
novel, naturally processed, CD4 T-cell epitope, E7 58–68 (CCKCDSTLRLC), restricted by the HLA-DR17 molecule.
This work was supported by the National Institutes of Health (R21CA094507).
An erratum to this article can be found at 相似文献
66.
Sushil K. Jain Thirunavukkarasu Velusamy Jennifer L. Croad Justin L. Rains Rebeca Bull 《Free radical biology & medicine》2009,46(12):1633-1638
This study examined the hypothesis that l-cysteine supplementation can lower insulin resistance, glycemia, oxidative stress, and markers of vascular inflammation in type 2 diabetes using Zucker diabetic fatty (ZDF) rats as a model. Starting at the age of 6 weeks, ZDF rats were supplemented orally (daily gavage, 8 weeks) with saline placebo (D) or l-cysteine (LC; 1 mg/kg bw) and fed a high-calorie diet. Six-week-old rats without any supplementation were considered baseline (BL) rats. D rats showed elevated fasting blood glucose, glycated Hb, CRP, and MCP-1 compared with BL rats in which there was no onset of diabetes. LC supplementation significantly lowered blood levels of glucose (18%, p = 0.05), glycated Hb (8%, p = 0.02), CRP (23%, p = 0.02), MCP-1 (32%, p = 0.01), and insulin resistance (25%) compared with levels seen in saline-supplemented D rats. There was a decrease in plasma protein oxidation levels (p < 0.01); however, GSH levels were similar in LC and D groups. Although LC did not change blood hematocrit or levels of transaminases, it did lower alkaline phosphatase (29%, p = 0.01) levels in comparison to D. Western blotting analyses of liver showed increased activation of NF-κB and Akt (50% pNF-κB and 20% pAkt) in D compared with BL rats. LC supplementation inhibited these effects (17% pAkt, 18% pNF-κB). This is the first report showing that l-cysteine supplementation can lower glycemia and markers of vascular inflammation in diabetes apparently by preventing NF-κB activation in a diabetic animal model. 相似文献
67.
In order to dissect the genetic regulation of leafblade morphogenesis, 16 genotypes of pea, constructed by combining the wild-type
and mutant alleles of MFP, AF, TL and UNI genes, were quantitatively phenotyped. The morphological features of the three domains of leafblades of four genotypes, unknown
earlier, were described. All the genotypes were found to differ in leafblade morphology. It was evident that MFP and TL functions
acted as repressor of pinna ramification, in the distal domain. These functions, with and without interaction with UNI, also
repressed the ramification of proximal pinnae in the absence of AF function. The expression of MFP and TL required UNI function.
AF function was found to control leafblade architecture multifariously. The earlier identified role of AF as a repressor of
UNI in the proximal domain was confirmed. Negative control of AF on the UNI-dependent pinna ramification in the distal domain was revealed. It was found that AF establishes a boundary between proximal
and distal domains and activates formation of leaflet pinnae in the proximal domain. 相似文献
68.
A Novel Pathway of Insulin Sensitivity in Chromogranin A Null Mice: A CRUCIAL ROLE FOR PANCREASTATIN IN GLUCOSE HOMEOSTASIS* 总被引:1,自引:0,他引:1
69.
Nikhil Jain Abu Rafay Khan Sushil Kumar Tomar Dipak Dutta Balaji Prakash 《Biochemical and biophysical research communications》2009,379(2):201-205
HflX is a GTP binding protein of unknown function. Based on the presence of the hflX gene in hflA operon, HflX was believed to be involved in the lytic-lysogenic decision during phage infection in Escherichia coli. We find that E. coli HflX binds 16S and 23S rRNA - the RNA components of 30S and 50S ribosomal subunits. Here, using purified ribosomal subunits, we show that HflX specifically interacts with the 50S. This finding is in line with the homology of HflX to GTPases involved in ribosome biogenesis. However, HflX-50S interaction is not limited to a specific nucleotide-bound state of the protein, and the presence of any of the nucleotides GTP/GDP/ATP/ADP is sufficient. In this respect, HflX is different from other GTPases. While E. coli HflX binds and hydrolyses both ATP and GTP, only the GTP hydrolysis activity is stimulated by 50S binding. This work uncovers interesting attributes of HflX in ribosome binding. 相似文献
70.
Krishan Kumar Megha Tharad Swetha Ganapathy Geeta Ram Azeet Narayan Jameel Ahmad Khan Rana Pratap Anamika Ghosh Sachin Kumar Samuchiwal Sushil Kumar Kuhulika Bhalla Deepti Gupta Krishnamurthy Natarajan Yogendra Singh Anand Ranganathan 《PloS one》2009,4(11)