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941.
Zubizarreta J Davis MC Hampikian G 《Human biology; an international record of research》2011,83(6):685-694
Fifty unrelated Basque males from southwest Idaho were typed for the 17 Y-STR loci in the Yfiler multiplex kit (DYS19, DYS389I, DYS389II, DYS390, DYS391, DYS392, DYS393, DYS437, DYS438, DYS439, DYS448, DYS456, DYS458, DYS635, YGATA H4.1 and DYS385a/b). In total, 42 haplotypes were identified, with no more than two individuals sharing a single haplotype. The haplotype diversity (HD) was 0.9935, and gene diversity (D) over loci was 0.457 ± 0.137. The Idaho Basque population was compared to the source population from the Basque autonomous region of Northern Spain and Southern France, as well as a United States Caucasian population. The haplotype diversity for the immigrant Basque sample is within 0.4% of the haplotype diversity of the European Basques (0.9903); thus the power of discrimination is similar for each population. The Idaho Basque population has less diversity in 9 out of 16 loci (considering DYS385a/b together) and 3% less diversity across all loci, compared to the European Basque population. A multidimensional scaling analysis (MDS) was created using pairwise R(ST) values to compare the Idaho Basques to other populations. Based upon R(ST) and F(ST) measures, no significant differentiation was found between the Idaho and source European Basque population. 相似文献
942.
Castellarin SD Gambetta GA Wada H Shackel KA Matthews MA 《Journal of experimental botany》2011,62(12):4345-4354
This study reports the first observations indicating the spatiotemporal relationships among genetic and physiological aspects of ripening in the berry of Vitis vinifera. At the onset of ripening in the red flesh variety Alicante Bouschet, colour development began in the flesh at the stylar end of the fruit and progressed toward the pedicel end flesh and into the skin. Tissue solute potential and cell turgor also decreased first in the flesh. The decrease in flesh solute potential was due to accumulation of sugars, glucose and fructose, an accumulation that is integral to ripening. Expression of the anthocyanin biosynthesis-related genes VvMybA and VvUFGT was linearly related to the decrease in solute potential. Expression of VvMybA, and to a lesser extent VvUFGT, was correspondingly low in green tissue, higher in the red, stylar end flesh of berries beginning to ripen, and greatest in red berries. In contrast, expression of the abscisic acid biosynthesis-related genes VvNCED1 and VvNCED2 was not correlated with the other spatiotemporal aspects of the onset of ripening. These results, together with earlier work showing that sugar accumulation and acid loss also begin in the stylar flesh in other varieties, indicate that ripening in the grape berry originates in the stylar end flesh. 相似文献
943.
944.
945.
We examined the association between rate of cholesterol esterification in plasma depleted of apolipoprotein B-containing lipoproteins (FER(HDL)), atherogenic index of plasma (AIP) [(log (TG/HDL-C)], concentrations, and size of lipoproteins and changes in coronary artery stenosis in participants in the HDL-Atherosclerosis Treatment Study. A total of 160 patients was treated with simvastatin (S), niacin (N), antioxidants (A) and placebo (P) in four regimens. FER(HDL) was measured using a radioassay; the size and concentration of lipoprotein subclasses were determined by nuclear magnetic resonance spectroscopy. The S+N and S+N+A therapy decreased AIP and FER(HDL), reduced total VLDL (mostly the large and medium size particles), decreased total LDL particles (mostly the small size), and increased total HDL particles (mostly the large size). FER(HDL) and AIP correlated negatively with particle sizes of HDL and LDL, positively with VLDL particle size, and closely with each other (r = 0.729). Changes in the proportions of small and large lipoprotein particles, which were reflected by FER(HDL) and AIP, corresponded with findings on coronary angiography. Logistic regression analysis of the changes in the coronary stenosis showed that probability of progression was best explained by FER(HDL) (P = 0.005). FER(HDL) and AIP reflect the actual composition of the lipoprotein spectrum and thus predict both the cardiovascular risk and effectiveness of therapy. AIP is already available for use in clinical practice as it can be readily calculated from the routine lipid profile. 相似文献
946.
947.
Ge L Gou X Yuan T Strout GW Nakashima J Blancaflor EB Tian HQ Russell SD 《Planta》2011,233(2):325-332
The promoter sequence of sperm-expressed gene, PzIPT isolated from the Svn (sperm associated with the vegetative nucleus) of Plumbago zeylanica, was fused to a green fluorescent protein (GFP) reporter sequence and transformed into Arabidopsis thaliana to better visualize the live behavior of angiosperm sperm cells. Angiosperm sperm cells are not independently motile, migrating
in a unique cell-within-a-cell configuration within the pollen tube. Sperm cells occur in association with the vegetative
nucleus forming a male germ unit (MGU). In Arabidopsis, GFP was expressed equally in both sperm cells and was observed using a spinning disk confocal microscope, which allowed
long duration observation of cells without bleaching or visible laser radiation damage. Pollen activation is reflected by
conspicuous movement of sperm and pollen cytoplasm. Upon pollen germination, sperm cells enter the forming tube and become
oriented, typically with a sperm cytoplasmic projection leading the sperm cells in the MGU, which remains intact throughout
normal pollen tube elongation. Maturational changes, including vacuolization, general rounding and entry into G2, were observed
during in vitro culture. When MGUs were experimentally disrupted by mild temperature elevation, sperm cells no longer tracked
the growth of the tube and separated from the MGU, providing critical direct evidence that the MGU is a functional unit required
for sperm transmission. 相似文献
948.
The performance of phylogenetic algorithms in estimating haplotype genealogies with migration 总被引:1,自引:0,他引:1
Genealogies estimated from haplotypic genetic data play a prominent role in various biological disciplines in general and in phylogenetics, population genetics and phylogeography in particular. Several software packages have specifically been developed for the purpose of reconstructing genealogies from closely related, and hence, highly similar haplotype sequence data. Here, we use simulated data sets to test the performance of traditional phylogenetic algorithms, neighbour-joining, maximum parsimony and maximum likelihood in estimating genealogies from nonrecombining haplotypic genetic data. We demonstrate that these methods are suitable for constructing genealogies from sets of closely related DNA sequences with or without migration. As genealogies based on phylogenetic reconstructions are fully resolved, but not necessarily bifurcating, and without reticulations, these approaches outperform widespread 'network' constructing methods. In our simulations of coalescent scenarios involving panmictic, symmetric and asymmetric migration, we found that phylogenetic reconstruction methods performed well, while the statistical parsimony approach as implemented in TCS performed poorly. Overall, parsimony as implemented in the PHYLIP package performed slightly better than other methods. We further point out that we are not making the case that widespread 'network' constructing methods are bad, but that traditional phylogenetic tree finding methods are applicable to haplotypic data and exhibit reasonable performance with respect to accuracy and robustness. We also discuss some of the problems of converting a tree to a haplotype genealogy, in particular that it is nonunique. 相似文献
949.
Yun J. Zhu Heather McCafferty Greg Osterman Steven Lim Ricelle Agbayani Axel Lehrer Susan Schenck Ewald Komor 《Transgenic research》2011,20(3):503-512
Sugarcane yellow leaf syndrome, characterized by a yellowing of the leaf midrib followed by leaf necrosis and growth suppression,
is caused by sugarcane yellow leaf virus (SCYLV). We produced SCYLV-resistant transgenic sugarcane from a susceptible cultivar (H62-4671) and determined the amount
of virus present following inoculation. The transgenic plants were produced through biolistic bombardment of cell cultures
with an untranslatable coat protein gene. Presence of the transgene in regenerated plants was confirmed using PCR and Southern
blot analysis. The transgenic lines were inoculated by viruliferous aphids and the level of SCYLV in the plants was determined.
Six out of nine transgenic lines had at least 103-fold lower virus titer than the non-transformed, susceptible parent line. This resistance level, as measured by virus titer
and symptom development, was similar to that of a resistant cultivar (H78-4153). The selected SCYLV-resistant transgenic sugarcane
lines will be available for integration of the resistance gene into other commercial cultivars and for quantification of viral
effects on yield. 相似文献
950.
Sette P Mu R Dussupt V Jiang J Snyder G Smith P Xiao TS Bouamr F 《Structure (London, England : 1993)》2011,19(10):1485-1495
Alix and cellular paralogs HD-PTP and Brox contain N-terminal Bro1 domains that bind ESCRT-III CHMP4. In contrast to HD-PTP and Brox, expression of the Bro1 domain of Alix alleviates HIV-1 release defects that result from interrupted access to ESCRT. In an attempt to elucidate this functional discrepancy, we solved the crystal structures of the Bro1 domains of HD-PTP and Brox. They revealed typical "boomerang" folds they share with the Bro1 Alix domain. However, they each contain unique structural features that may be relevant to their specific function(s). In particular, phenylalanine residue in position 105 (Phe105) of Alix belongs to a long loop that is unique to its Bro1 domain. Concurrently, mutation of Phe105 and surrounding residues at the tip of the loop compromise the function of Alix in HIV-1 budding without affecting its interactions with Gag or CHMP4. These studies identify a new functional determinant in the Bro1 domain of Alix. 相似文献