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131.
William D. Hopkins Jamie L. Russell Margaret Remkus Hani Freeman Steven J. Schapiro 《International journal of primatology》2007,28(6):1315-1326
Grooming is a complex set of motor actions, common in highly social primates. We tested for asymmetries in hand use during
unimanual and bimanual allogrooming in 215 captive chimpanzees. In addition to hand use, we coded in the ethogram whether
the manual grooming action co-occurred with the use of the mouth. Overall, grooming did not elicit strong handedness at the
individual level, but there is a small yet significant population-level right-hand bias for bimanual grooming. Mouth use during
grooming had no influence on hand use. A comparison of the findings with previously published data on handedness for grooming
in wild chimpanzees suggests that wild apes are more right-handed than captive individuals are for allogrooming. Collectively,
the results suggest that role differentiation of the hands is an important factor in the assessment of handedness for grooming,
and perhaps additional manual actions of chimpanzees and other primates. 相似文献
132.
Suleiman H Heudobler D Raschta AS Zhao Y Zhao Q Hertting I Vitzthum H Moeller MJ Holzman LB Rachel R Johnson R Westphal H Rascle A Witzgall R 《Developmental biology》2007,304(2):701-712
Patients with nail-patella syndrome, which among other symptoms also includes podocyte-associated renal failure, suffer from mutations in the LMX1B gene. The disease severity among patients is quite variable and has given rise to speculations on the presence of modifier genes. Promising candidates for modifier proteins are the proteins interacting with LMX1B, such as LDB1 and E47. Since human kidney samples from patients are difficult to obtain, conventional Lmx1b knock-out mice have been extremely valuable to study the role of Lmx1b in podocyte differentiation. In contrast to findings in these mice, however, in which a downregulation of the Col4a3, Col4a4 and Nphs2 genes has been described, no such changes have been detected in kidney biopsies from patients. We now report on our results on the characterization of constitutive podocyte-specific Lmx1b, Ldb1 and E2a knock-out mice. Constitutive podocyte-specific Lmx1b knock-out mice survive for approximately 2 weeks after birth and do not present with a downregulation of the Col4a3, Col4a4 and Nphs2 genes, therefore they mimic the human disease more closely. The podocyte-specific Ldb1 knock-out mice survive longer, but then also succumb to renal failure, whereas the E2a knock-out mice show no renal symptoms for at least 6 months after birth. We conclude that LDB1, but not E2A is a promising candidate as a modifier gene in patients with nail-patella syndrome. 相似文献
133.
Yimu Zhao Naimeh Rafatian Nicole T. Feric Brian J. Cox Roozbeh Aschar-Sobbi Erika Yan Wang Praful Aggarwal Boyang Zhang Genevieve Conant Kacey Ronaldson-Bouchard Aric Pahnke Stephanie Protze Jee Hoon Lee Locke Davenport Huyer Danica Jekic Anastasia Wickeler Hani E. Naguib Gordon M. Keller Milica Radisic 《Cell》2019,176(4):913-927.e18
134.
135.
Hani Susianti Atma Gunawan Jayarani Fatimah Putri Basuki B Purnomo Kusworini Handono Handono Kalim 《Bioinformation》2014,10(8):487-490
The TGF-β1 cytokine concentration is known to be higher in nephritis with implied Lupus Nephritis severity. The production of
TGF-β1 cytokine is associated with G915C polymorphism. Therefore, it is of interest to study G915C polymorphism. The G915C
polymorphism changes codon 25 which encodes arginine into proline in the signal peptide of TGF-β1. The amino acid substitution
affects signal peptide properties that may inhibit the transport of TGF-β1 into the endoplasmic reticulum and eventually decline
the cytokine production. Hence, the effect of G915C polymorphism on the properties of the signal peptide, the ability of TGF-β1
transport into the endoplasmic reticulum and the concentrations of urinary TGF-β1 in Lupus Nephritis patients was studied. The
arginine substitution into proline decreased the polarity of the signal peptide for TGF-β1. The increased hydrophobicity with
increased binding energy of the signal peptide for TGF-β1 to Signal Recognition Particle (SRP) and translocon is shown. This
implies decreased protein complex stability in potentially blocking the transport of TGF-β1 into the endoplasmic reticulum. This
transport retention possibly hampers the synthesis and maturation of TGF-β1 leading to decreased cytokine production. 相似文献
136.
MR Hussain NA Shaik JY Al-Aama HZ Asfour F Subhani Khan TA Masoodi MA Khan NS Shaik 《Gene》2012,508(2):188-196
BRAF gene mutations are frequently seen in both inherited and somatic diseases. However, the harmful mutations for BRAF gene have not been predicted in silico. Owing to the importance of BRAF gene in cell division, differentiation and secretion processes, the functional analysis was carried out to explore the possible association between genetic mutations and phenotypic variations. Genomic analysis of BRAF was initiated with SIFT followed by PolyPhen and SNPs&GO servers to retrieve the 85 deleterious non-synonymous SNPs (nsSNPs) from dbSNP. A total of 5 mutations i.e. c.406T>G (S136A), c.1446G>T (R462I), c.1556 A>G (K499E), c.1860 T>A (V600E) and c.2352 C>T (P764L) that are found to exert benign effects on the BRAF protein structure and function were chosen for further analysis. Protein structural analysis with these amino acid variants was performed by using I-Mutant, FOLD-X, HOPE, NetSurfP, Swiss PDB viewer, Chimera and NOMAD-Ref servers to check their solvent accessibility, molecular dynamics and energy minimization calculations. Our in silico analysis suggested that S136A and P764L variants of BRAF could directly or indirectly destabilize the amino acid interactions and hydrogen bond networks thus explain the functional deviations of protein to some extent. Screening for BRAF, S136A and P764Lvariants may be useful for disease molecular diagnosis and also to design the molecular inhibitors of BRAF pathways. 相似文献
137.
138.
Involvement of indole‐3‐acetic acid (IAA), produced by the microalgae‐growth‐promoting bacteria Azospirillum brasilens and A. lipoferum, in promoting growth of the microalga Chlorella vulgaris Beij. was studied. Four wildtype strains of Azospirillum and their IAA‐deficient mutants were co‐immobilized with C. vulgaris in alginate beads. Cultures were grown in synthetic growth medium supplemented with tryptophan. Growth promotion of microalgae and production of exogenous IAA by Azospirillum spp. were monitored. All wildtype Azospirillum spp. produced significant but varying amounts of IAA, while their mutant forms produced significantly less. The results demonstrated a significant growth promotion in Chlorella cultures when immobilized with the four wildtype strains of Azospirillum, while very low or no enhanced growth was induced by the four IAA‐deficient mutants, compared to when C. vulgaris is immobilized alone. A complementation experiment, where an IAA‐attenuated mutant (A. brasilense SpM7918) was supplemented with IAA produced by its parental wildtype strain (A. brasilense Sp6), restored growth promotion in the microalgae‐mutant culture. 相似文献
139.
Enzymatic activities of glutamate dehydrogenase (GDH) and glutamine synthetase (GS) participating in the nitrogen metabolism and related ammonium absorption were assayed after the microalga Chlorella vulgaris Beij. was jointly immobilized with the microalgae‐growth‐promoting bacterium Azospirillum brasilense. At initial concentrations of 3, 6, and 10 mg · L?1 NH4+, joint immobilization enhances growth of C. vulgaris but does not affect ammonium absorption capacity of the microalga. However, at 8 mg · L?1 NH4+, joint immobilization enhanced ammonium absorption by the microalga without affecting the growth of the microalgal population. Correlations between absorption of ammonium per cell and per culture showed direct (negative and positive) linear correlations between these parameters and microalga populations at 3, 6, and 10 mg · L?1 NH4+, but not at 8 mg · L?1 NH4+, where the highest absorption of ammonium occurred. In all cultures, immobilized and jointly immobilized, having the four initial ammonium concentrations, enzymatic activities of Chlorella are affected by A. brasilense. Regardless of the initial concentration of ammonium, GS activity in C. vulgaris was always higher when jointly immobilized and determined on a per‐cell basis. When jointly immobilized, only at an initial concentration of 8 mg · L?1 NH4+ was GDH activity per cell higher. 相似文献
140.
Marie-Claude Julien Patrice Dion Carole Lafrenire Hani Antoun Pascal Drouin 《Applied microbiology》2008,74(20):6348-6357
A PCR-denaturing gradient gel electrophoresis (DGGE) method was used to examine on-farm sources of Clostridium cluster I strains in four dairy farms over 2 years. Conventional microbiological analysis was used in parallel to monitor size of clostridial populations present in various components of the milk production chain (soil, forage, grass silage, maize silage, dry hay, and raw milk). PCR amplification with Clostridium cluster I-specific 16S rRNA gene primers followed by DGGE separation yielded a total of 47 operational taxonomic units (OTUs), which varied greatly with respect to frequency of occurrence. Some OTUs were found only in forage, and forage profiles differed according to farm location (southern or northern Québec). More clostridial contamination was found in maize silage than in grass silage. Milk represented a potential environment for certain OTUs. No OTU was milk specific, indicating that OTUs originated from other environments. Most (83%) of the OTUs detected in raw milk were also found in grass or maize silage. Milk DGGE profiles differed according to farm and sampling year and fit into two distinct categories. One milk profile category was characterized by the presence of a few dominant OTUs, the presence of which appeared to be more related to farm management than to feed contamination. OTUs were more varied in the second profile category. The identities of certain OTUs frequently found in milk were resolved by cloning and sequencing. Clostridium disporicum was identified as an important member of clostridial populations transmitted to milk. Clostridium tyrobutyricum was consistently found in milk and was widespread in the other farm environments examined. 相似文献