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81.
T. Ogata Keiko Wakui Koji Muroya Hirofumi Ohashi Nobutake Matsuo Donna M. Brown Takashi Ishii Yoshimitsu Fukushima 《Human genetics》1998,103(1):51-56
This paper describes a female infant with microphthalmia with linear skin defects syndrome (MLS) and monosomy for the Xp22
region. Her clinical features included right microphthalmia and sclerocornea, left corneal opacity, linear red rash and scar-like
skin lesion on the nose and cheeks, and absence of the corpus callosum. Cytogenetic studies revealed a 45,X[18]/46,X,r(X)(p22q21)
[24]/46,X,del(X)(p22)[58] karyotype. Fluorescence in situ hybridization analysis showed that the ring X chromosome was positive
for DXZ1 and XIST and negative for the Xp and Xq telomeric regions, whereas the deleted X chromosome was positive for DXZ1,
XIST, and the Xq telomeric region and negative for the Xp telomeric region. Microsatellite analysis for 19 loci at the X-differential
region of Xp22 disclosed monosomy for Xp22 involving the critical region for the MLS gene, with the breakpoint between DXS1053
and DXS418. X-inactivation analysis for the methylation status of the PGK gene indicated the presence of inactive normal X
chromosomes. The Xp22 deletion of our patient is the largest in MLS patients with molecularly defined Xp22 monosomy. Nevertheless,
the result of X-inactivation analysis implies that the normal X chromosomes in the 46,X,del(X)(p22) cell lineage were more
or less subject to X-inactivation, because normal X chromosomes in the 45,X and 46,X,r(X)(p22q21) cell lineages are unlikely
to undergo X-inactivation. This supports the notion that functional absence of the MLS gene caused by inactivation of the
normal X chromosome plays a pivotal role in the development of MLS in patients with Xp22 monosomy.
Received: 16 December 1997 / Accepted: 25 February 1998 相似文献
82.
83.
David E. Lucero Wilma Ribera Juan Carlos Pizarro Carlos Plaza Levi W. Gordon Reynaldo Pe?a Jr Leslie A. Morrissey Donna M. Rizzo Lori Stevens 《PLoS neglected tropical diseases》2014,8(12)
Background
In this study we compared the utility of two molecular biology techniques, cloning of the mitochondrial 12S ribosomal RNA gene and hydrolysis probe-based qPCR, to identify blood meal sources of sylvatic Chagas disease insect vectors collected with live-bait mouse traps (also known as Noireau traps). Fourteen T. guasayana were collected from six georeferenced trap locations in the Andean highlands of the department of Chuquisaca, Bolivia.Methodology/Principal Findings
We detected four blood meals sources with the cloning assay: seven samples were positive for human (Homo sapiens), five for chicken (Gallus gallus) and unicolored blackbird (Agelasticus cyanopus), and one for opossum (Monodelphis domestica). Using the qPCR assay we detected chicken (13 vectors), and human (14 vectors) blood meals as well as an additional blood meal source, Canis sp. (4 vectors).Conclusions/Significance
We show that cloning of 12S PCR products, which avoids bias associated with developing primers based on a priori knowledge, detected blood meal sources not previously considered and that species-specific qPCR is more sensitive. All samples identified as positive for a specific blood meal source by the cloning assay were also positive by qPCR. However, not all samples positive by qPCR were positive by cloning. We show the power of combining the cloning assay with the highly sensitive hydrolysis probe-based qPCR assay provides a more complete picture of blood meal sources for insect disease vectors. 相似文献84.
Spray drying is a way to generate protein solids (powders), which is also true for lyophilization. Sugars are used to protect proteins from conformational changes and chemical degradations arising from drying processes and storage conditions such as the humidity. The influence of trehalose and humidity on the conformation and hydration of spray-dried recombinant human granolucyte colony stimulating factor (rhG-CSF) and recombinant consensus interferon-alpha (rConIFN) was investigated using Fourier transform IR spectroscopy. The spectral analysis of spray-dried powders in the amide I region demonstrated that trehalose stabilized the alpha-helical conformation of both rhG-CSF and rConIFN proteins. Exposure of the pure protein powders to 33% relative humidity (RH) resulted in the formation of beta sheets and loss of turns but no change in alpha-helical structure. Trehalose reduced the magnitude of the changes in beta sheets and turns. Exposure of the pure protein powders to 75% RH resulted in the loss of alpha-helical conformation with a corresponding increase in beta structures (beta sheets and turns). Trehalose did not protect proteins from the loss of alpha-helical structures, but it reduced the formation of antiparallel beta sheets. Hydrogen-deuterium exchange (H-D exchange) was used to further characterize these hydration-induced conformational changes. At 33% RH the percent exchange of the protein decreased with increasing trehalose content, indicating a greater protection of the protein from H-D exchange by a higher concentration of trehalose. Such protection correlates with decreased conformational changes of the protein by trehalose at this humidity. At 75% RH the degree of H-D exchange of the protein was insensitive to the powder composition in all powders. Surprisingly, the H-D exchange of trehalose was low at about 20-25%, which was nearly independent of the protein/trehalose ratio and humidity, indicating that the exchangeable protons on trehalose molecules are highly protected in protein-containing powders. The observed protein hydration is related to the effect of trehalose on the conformational changes of the protein under humidity. 相似文献
85.
Arnett DK Miller MB Coon H Ellison RC North KE Province M Leppert M Eckfeldt JH 《Human genetics》2004,115(6):468-474
Recent reports implicate chromosomal regions linked to inter-individual variation in plasma triglycerides. We conducted genome-wide scans to replicate these linkages and/or identify other loci influencing plasma triglycerides in the NHLBI Family Heart Study (FHS). Data were obtained for 501 three-generational families. Genotyping was done by the Utah Molecular Genetics Laboratory and NHLBI Mammalian Genotyping Service; markers from both were placed on one genetic map. Analysis was done using multipoint variance components linkage. Fasting plasma triglycerides were log-transformed and age-, sex-, and field center-adjusted; suggestive linkage evidence was found on chromosome 8 (LOD=2.80 at 89 cM, marker D8S1141). Further adjustment for waist girth, BMI, diabetes, hypertension, and lipid-lowering drugs suggested linkage regions on chromosomes 6 (LOD=2.29 at 79 cM, marker D6S295) and 15 (LOD=1.85 at 43 cM, marker D15S659). Since HDL is correlated with triglycerides and because it was linked to this region on chromosome 15 in FHS, we created a composite triglyceride–HDL phenotype. The combined phenotype LOD score was 3.0 at the same marker on chromosome 15. Chromosome 15 likely harbors a susceptibility locus with an influence on triglycerides and HDL. Regions on chromosomes 6 and 8 may also contain loci contributing to inter-individual variation in plasma triglycerides. 相似文献
86.
87.
Matchkov VV Moeller-Nielsen N Dam VS Nourian Z Briggs Boedtkjer DM Aalkjaer C 《American journal of physiology. Heart and circulatory physiology》2012,303(1):H36-H46
The specific role of different isoforms of the Na,K-pump in the vascular wall is still under debate. We have previously suggested that the α(2) isoform of the Na,K-pump (α(2)), Na(+), Ca(2+)-exchange (NCX), and connexin43 form a regulatory microdomain in smooth muscle cells (SMCs), which controls intercellular communication and contractile properties of the vascular wall. We have tested this hypothesis by downregulating α(2) in cultured SMCs and in small arteries with siRNA in vivo. Intercellular communication was assessed by using membrane capacitance measurements. Arteries transfected in vivo were tested for isometric and isobaric force development in vitro; [Ca(2+)](i) was measured simultaneously. Cultured rat SMCs were well-coupled electrically, but 10 μM ouabain uncoupled them. Downregulation of α(2) reduced electrical coupling between SMCs and made them insensitive to ouabain. Downregulation of α(2) in small arteries was accompanied with significant reduction in NCX expression. Acetylcholine-induced relaxation was not different between the groups, but the endothelium-dependent hyperpolarizing factor-like component of the response was significantly diminished in α(2)-downregulated arteries. Micromolar ouabain reduced in a concentration-dependent manner the amplitude of norepinephrine (NE)-induced vasomotion. Sixty percent of the α(2)-downregulated arteries did not have vasomotion, and vasomotion in the remaining 40% was ouabain insensitive. Although ouabain increased the sensitivity to NE in the control arteries, it had no effect on α(2)-downregulated arteries. In the presence of a low NE concentration the α(2)-downregulated arteries had higher [Ca(2+)](i) and tone. However, the NE EC50 was reduced under isometric conditions, and maximal contraction was reduced under isometric and isobaric conditions. The latter was caused by a reduced Ca(2+)-sensitivity. The α(2)-downregulated arteries also had reduced contraction to vasopressin, whereas the contractile response to high K(+) was not affected. Our results demonstrate the importance of α(2) for intercellular coupling in the vascular wall and its involvement in the regulation of vascular tone. 相似文献
88.
89.
Kockx M Dinnes DL Huang KY Sharpe LJ Jessup W Brown AJ Kritharides L 《The Biochemical journal》2012,447(1):51-60
Cholesterol excess is typical of various diseases including atherosclerosis. We have investigated whether cholesterol accumulation in the ER (endoplasmic reticulum) can inhibit exit of vesicular cargo and secretion of proteins by studying apoE (apolipoprotein E), a significant glycoprotein in human health and disease. CHO (Chinese hamster ovary) cells expressing human apoE under a cholesterol-independent promoter incubated with cholesterol-cyclodextrin complexes showed increased levels of cellular free and esterified cholesterol, inhibition of SREBP-2 (sterol-regulatory-element-binding protein 2) processing, and a mild induction of ER stress, indicating significant accumulation of cholesterol in the ER. Secretion of apoE was markedly inhibited by cholesterol accumulation, and similar effects were observed in cells enriched with lipoprotein-derived cholesterol and in primary human macrophages. Removal of excess cholesterol by a cyclodextrin vehicle restored apoE secretion, indicating that the transport defect was reversible. That cholesterol impaired protein trafficking was supported by the cellular accumulation of less sialylated apoE glycoforms, and by direct visualization of altered ER to Golgi transport of thermo-reversible VSVG (vesicular stomatitis virus glycoprotein) linked to GFP (green fluorescent protein). We conclude that intracellular accumulation of cholesterol in the ER reversibly inhibits protein transport and secretion. Strategies to correct ER cholesterol may restore homoeostatic processes and intracellular protein transport in conditions characterized by cholesterol excess. 相似文献
90.
Edmond K. Kabagambe Jose M. Ordovas Paul N. Hopkins Michael Y. Tsai Donna K. Arnett 《PloS one》2012,7(10)