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The salivary flow rate and composition of whole and parotid resting and stimulated saliva in young and old healthy subjects 总被引:1,自引:0,他引:1
H Ben-Aryeh A Shalev R Szargel A Laor D Laufer D Gutman 《Biochemical medicine and metabolic biology》1986,36(2):260-265
Resting and stimulated whole and parotid salivary composition and flow rate were examined in 63 healthy volunteers. No significant differences were found between the young and old in secretion rates and salivary concentrations of sodium, potassium, calcium, magnesium, and total protein. The activity of amylase in the resting and stimulated parotid saliva was significantly lower in the old. 相似文献
3.
Idan Segev Alon Friedman Edward L. White Michael J. Gutnick 《Journal of computational neuroscience》1995,2(2):117-130
We built a passive compartmental model of a cortical spiny stellate cell from the barrel cortex of the mouse that had been reconstructed in its entirety from electron microscopic analysis of serial thin sections (White and Rock, 1980). Morphological data included dimensions of soma and all five dendrites, neck lengths and head diameters of all 380 spines (a uniform neck diameter of 0.1 m was assumed), locations of all symmetrical and asymmetrical (axo-spinous) synapses, and locations of all 43 thalamocortical (TC) synapses (as identified from the consequences of a prior thalamic lesion). In the model, unitary excitatory synaptic inputs had a peak conductance change of 0.5 nS at 0.2 msec; conclusions were robust over a wide range of assumed passive-membrane parameters. When recorded at the soma, all unitary EPSPs, which were initiated at the spine heads, were relatively iso-efficient; each produced about 1 mV somatic depolarization regardless of spine location or geometry. However, in the spine heads there was a twentyfold variation in EPSP amplitudes, largely reflecting the variation in spine neck lengths. Synchronous activation of the TC synapses produced a somatic depolarization probably sufficient to fire the neuron; doubling or halving the TC spine neck diameters had only minimal effect on the amplitude of the composite TC-EPSP. As have others, we also conclude that from a somato-centric viewpoint, changes in spine geometry would have relatively little direct influence on amplitudes of EPSPs recorded at the soma, especially for a distributed, synchronously activated input such as the TC pathway. However, consideration of the detailed morphology of an entire neuron indicates that, from a dendro-centric point of view, changes in spine dimension can have a very significant electrical impact on local processing near the sites of input. 相似文献
4.
Progesterone levels in fore milk, determined by a highly specific radioimmunoassay, were compared for the assessment of estrus by a veteran herdsman and an experienced inseminator, in cows presented for insemination. In addition, an examination was made of the relative accuracy of using milk progesterone levels for the determination of pregnancy at 24, 40 and 44 days after insemination, as compared with rectal palpation at 45–50 days post-breeding.Fat-free fore milk progesterone levels were similar to jugular plasma levels at 24 days post-insemination and reached roughly 60% of the level of unextracted fore milk at this time. Accuracy of estrus diagnosis by herdsman, inseminator and milk progesterone level was 84%, 93% and 96%, respectively. For pregnancy diagnosis, milk progesterone determination in 85 cows showed 78% accuracy in predicting pregnancy and 100% accuracy in predicting non-pregnancy. At 40 days post-insemination false positives dropped to 10% and at 44 days only 7% of the cows were incorrectly diagnosed as pregnant. The false positives in this study were largely due to embryonic mortality as reflected by abnormal intervals of return to estrus. Two milk progesterone determinations, at 24 and either 40 or 44 days post-insemination ensure maximum reliability for early pregnancy diagnosis. 相似文献
5.
The segregation pattern of a translocation quadrivalent 总被引:1,自引:1,他引:0
The segregation pattern of a translocation quadrivalent was studied in three hybrid families of the tetraploid (2n=28) oat, of the Avena strigosa polyploid complex. The rate of IV formation in F1 was high and the fertility was normal. The adjacent-alternate orientation of this quadrivalent was very variable. Conspicuous variation in this frequency was found between anthers of the same floret and between florets. The alternate type was usually more common toward the end of MI. The adjacent-alternate ratio was found to be an unreliable measure for calculating the type of gametes produced by the F1 and the F2 plants derived from them. An attempt was made to determine the type of viable gametes produced on the F1 and their frequency by examining the cytology of F2 plants. The various combinations of the chromosomes of the translocation complex expected in the F2 plants were derived and their expected frequencies calculated by taking into account chiasma formation at the chromosome ends and various restrictions of gamete viability. In none of the three hybrid families F2 individuals were found to produce trivalents as the most complex chromosome configuration, indicating that one type of gamete derived from adjacent separation was not formed. The 11 ratio between F2 plants having only bivalents (2II) and those with F 1-like quadrivalent configuration R(c), expected when gametes resulting from alternate separation are fully functional, with the exclusion of other types, was not found. That ratio 2II/R(c), was 2-1/3 in the various families. The cytology of selected F3 individuals basically followed the predictions based on chromosome association in the F2. 相似文献
6.
Conjunctivitis and blepharospasm were observed in a litter of four, 2-week-old New Zealand white rabbits. Corneal opacity and neovascularization of the cornea and entropion of the upper eyelids were observed when the rabbits were examined 10 weeks later. Conjunctival cultures of these rabbits yielded normal bacterial flora. Treatment with a steroid-antibiotic ophthalmic ointment did not alter the ocular abnormalities. Surgical correction of the entropion resulted in a complete regression of all clinical signs. 相似文献
7.
Michal S. Shoshan Edit Y. Tshuva Deborah E. Shalev 《Journal of visualized experiments : JoVE》2013,(82)
Copper (I) binding by metallochaperone transport proteins prevents copper oxidation and release of the toxic ions that may participate in harmful redox reactions. The Cu (I) complex of the peptide model of a Cu (I) binding metallochaperone protein, which includes the sequence MTCSGCSRPG (underlined is conserved), was determined in solution under inert conditions by NMR spectroscopy.NMR is a widely accepted technique for the determination of solution structures of proteins and peptides. Due to difficulty in crystallization to provide single crystals suitable for X-ray crystallography, the NMR technique is extremely valuable, especially as it provides information on the solution state rather than the solid state. Herein we describe all steps that are required for full three-dimensional structure determinations by NMR. The protocol includes sample preparation in an NMR tube, 1D and 2D data collection and processing, peak assignment and integration, molecular mechanics calculations, and structure analysis. Importantly, the analysis was first conducted without any preset metal-ligand bonds, to assure a reliable structure determination in an unbiased manner. 相似文献
8.
Copy number variants (CNVs) are thought to play an important role in the predisposition to autism spectrum disorder (ASD). However, their relatively low frequency and widespread genomic distribution complicates their accurate characterization and utilization for clinical genetics purposes. Here we present a comprehensive analysis of multi-study, genome-wide CNV data from AutDB (http://mindspec.org/autdb.html), a genetic database that accommodates detailed annotations of published scientific reports of CNVs identified in ASD individuals. Overall, we evaluated 4,926 CNVs in 2,373 ASD subjects from 48 scientific reports, encompassing ∼2.12×109 bp of genomic data. Remarkable variation was seen in CNV size, with duplications being significantly larger than deletions, (P = 3×10−105; Wilcoxon rank sum test). Examination of the CNV burden across the genome revealed 11 loci with a significant excess of CNVs among ASD subjects (P<7×10−7). Altogether, these loci covered 15,610 kb of the genome and contained 166 genes. Remarkable variation was seen both in locus size (20 - 4950 kb), and gene content, with seven multigenic (≥3 genes) and four monogenic loci. CNV data from control populations was used to further refine the boundaries of these ASD susceptibility loci. Interestingly, our analysis indicates that 15q11.2-13.3, a genomic region prone to chromosomal rearrangements of various sizes, contains three distinct ASD susceptibility CNV loci that vary in their genomic boundaries, CNV types, inheritance patterns, and overlap with CNVs from control populations. In summary, our analysis of AutDB CNV data provides valuable insights into the genomic characteristics of ASD susceptibility CNV loci and could therefore be utilized in various clinical settings and facilitate future genetic research of this disorder. 相似文献
9.
10.
Rotem Kadir Tamar Harel Barak Markus Yonatan Perez Anna Bakhrat Idan Cohen Michael Volodarsky Miora Feintsein-Linial Elana Chervinski Joel Zlotogora Sara Sivan Ramon Y. Birnbaum Uri Abdu Stavit Shalev Ohad S. Birk 《PLoS genetics》2016,12(3)
Primary microcephaly is a congenital neurodevelopmental disorder of reduced head circumference and brain volume, with fewer neurons in the cortex of the developing brain due to premature transition between symmetrical and asymmetrical cellular division of the neuronal stem cell layer during neurogenesis. We now show through linkage analysis and whole exome sequencing, that a dominant mutation in ALFY, encoding an autophagy scaffold protein, causes human primary microcephaly. We demonstrate the dominant effect of the mutation in drosophila: transgenic flies harboring the human mutant allele display small brain volume, recapitulating the disease phenotype. Moreover, eye-specific expression of human mutant ALFY causes rough eye phenotype. In molecular terms, we demonstrate that normally ALFY attenuates the canonical Wnt signaling pathway via autophagy-dependent removal specifically of aggregates of DVL3 and not of Dvl1 or Dvl2. Thus, autophagic attenuation of Wnt signaling through removal of Dvl3 aggregates by ALFY acts in determining human brain size. 相似文献