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1.
Physicians with an interest in pain have long suggested that the poor complain more and have a higher prevalence of neuroticism than do higher social groups. This assumption was tested by analysing the pain patterns in 500 consecutive patients attending a pain relief clinic. Results implied that scores for presenting pain, anxiety, and depression were similar to all social groups. After treatment scores for residual pain were significantly lower in all social classes, with greatest reduction in classes III, IV, and V. Almost identical results were obtained in a subgroup of patients with cancer but not in a subgroup with sciatica. That patients from the lower social classes have a higher perception of pain and are more neurotic than other group is a myth, probably resulting from poor communication between clinicians and patients of dissimilar socioeconomic class. 相似文献
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Victor F. Medina Peter M. Jeffers Steven L. Larson Waleska Perez 《International journal of phytoremediation》2000,2(4):287-295
Bleach treatment of plants was studied as a simple alternative to axenic tissue cultures for demonstrating phytodegradation of aqueous and gas-phase environmental contaminants. Parrotfeather (Myriophyllum aquaticum), spinach (Spinacia oleracea), and wheat (Triticum aestivum) were exposed to 0.525% NaC10 solutions for 15 s, then rinsed in deionized water. Plate counts indicated that 97 to 100% of viable bacteria were removed from parrotfeather and spinach. Transformation rates for 2,4,6-trinitrotoluene (TNT) by bleached and untreated parrotfeather were virtually identical. Similarly, treated and untreated spinach, wheat heads, and wheat leaves removed methyl bromide (MeBr) from air at the same rates. However, wheat root with attendant adhering soil was rendered inactive by bleach treatment. Parrotfeather roots examined by dissecting microscope and by electron microscope showed no significant damage caused by bleach treatment. 相似文献
4.
Globin synthesis on reticulocyte membrane-bound ribosomes 总被引:1,自引:0,他引:1
W R Woodward S D Adamson H M McQueen J W Larson S M Estvanik P Wilairat E Herbert 《The Journal of biological chemistry》1973,248(5):1556-1561
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Purification and partial characterization of a bovine epidermal growth factor-like polypeptide 总被引:1,自引:0,他引:1
J C Byatt B R Larson M P Baganoff M F McGrath R J Collier 《Biochemistry international》1990,20(6):1179-1187
A heterologous radioreceptor assay was developed to follow the purification of an EGF-like polypeptide from bovine kidney. Purification of the growth factor was facilitated by the use of a novel affinity column using fixed A431 cells attached to sephadex beads. The mol. wt. of the purified EGF-LP was estimated to be 5480 from the amino acid composition. The purified EGF-like polypeptide stimulated the proliferation of bovine mammary epithelial cells and appeared to be equipotent to mouse EGF. Available evidence suggests that the purified molecule is distinct from bovine TGF-alpha. 相似文献
7.
Mindaugas Tamoinas Emilija V. Plorina Marta Lange Aleksandrs Derjabo Ilona Kuzmina Dmitrijs Bizuks Janis Spigulis 《Journal of biophotonics》2020,13(3)
This clinical study is a first attempt to use autofluorescence for recurrence diagnosis of skin cancer in postoperative scars. The proposed diagnostic parameter is based on a reduction in scar autofluorescence, evaluated in the green spectral channel. The validity of the method has been tested on 110 postoperative scars from 56 patients suspected of non‐melanoma skin cancer, with eight patients (13 scars) available for the repeated examination. The recurrence diagnosis within a scar has been made after two subsequent autofluorescence check‐ups, representing the temporal difference between the scar autofluorescence amplitudes as a vector. The recognition of recurrence has been discussed to represent the significant deviations from the value of vector angle θ. This new autofluorescence‐based method can be easily integrated into the postoperative monitoring of surgical scars and can help diagnose the recurrence of skin cancer from the early stage of scar development. 相似文献
8.
Dynamics of telomere length variation in Tetrahymena thermophila 总被引:29,自引:0,他引:29
We have analyzed the mechanism and dynamics of telomere length variation in the macronucleus of Tetrahymena thermophila. In a newly differentiated macronucleus, the average length of the telomeric repeated sequence, (C4A2 X T2G4)n, is closely regulated. In contrast, in vegetatively dividing cells in log phase, all macronuclear telomeric sequences lengthen coordinately by 3-10 bp per generation until up to 1000 bp are added. In both elongated and short telomeres, characteristic single-stranded breaks on both strands are distally located. Reduction of elongated telomeres to their original length involves either the appearance of a novel type of variant cell, incapable of net telomere elongation, or, under stationary phase conditions, a reversible removal of telomeric sequences. The demonstration that telomeres are dynamic structures provides evidence for a model of telomere length regulation by activities that add and remove telomeric repeats. 相似文献
9.
We analyzed the ability of DNA polymerases to bypass damage on single- and double-stranded templates. In vitro DNA synthesis was studied on UV-irradiated and polyaromatic hydrocarbon reacted (benzo[a]pyrenediol epoxide and oxiranylpyrene) double-stranded templates by a protocol involving initiation on a uniquely nicked circular double-stranded template. The template was prepared by treating single-stranded (+)M13mp2 circular strands with mutagen and then hybridizing with restricted M13 RFmp2, followed by isolation of the nicked RFII forms. The protocol permits either (+), (-), or both strands to carry lesions. We found that the rules for termination and bypass of lesions previously observed with single-stranded DNA templates also hold for double-stranded templates. Termination of synthesis occurs primarily one nucleotide 3' to the lesion in the template strand. Bypass of UV-induced lesions can be followed in a series of three partial reactions in the presence of Mn2+ and dGMP, which relax the specificity of nucleotide insertion and 3'----5' exonuclease activity, respectively. There is no evidence for greater permissivity of bypass in double-as opposed to single-stranded templates. As with single-stranded templates, purines and preferentially deoxyadenosine (dA) are inserted opposite lesions. Lesions in the nontemplate strand elicit neither termination nor pausing. The addition of Rec A protein resulted in a measurable increase of bypass in this system. 相似文献
10.
The replication advantage of a free linear rRNA gene is restored by somatic recombination in Tetrahymena thermophila. 总被引:9,自引:2,他引:7 下载免费PDF全文
P C Yaeger E Orias W L Shaiu D D Larson E H Blackburn 《Molecular and cellular biology》1989,9(2):452-460
The autonomously replicating rRNA genes (rDNA) in the somatic nucleus of Tetrahymena thermophila are maintained at a copy number of approximately 10(4) per nucleus. A mutant in which the replication properties of this molecule were altered was isolated and characterized. This mutation of inbred strain C3, named rmm4, was shown to have the same effect on rDNA replication and to be associated with the same 1-base-pair (bp) deletion as the previously reported, independently derived rmm1 mutation (D. L. Larson, E. H. Blackburn, P. C. Yaeger, and E. Orias, Cell 47:229-240, 1986). The rDNA of inbred strain B, which is at a replicational disadvantage compared with wild-type C3 rDNA, has a 42-bp deletion. This deletion is separated by 25 bp from the 1-bp deletion of rmm4 or rmm1. Southern blot analysis and DNA sequencing revealed that during prolonged vegetative divisions of C3-rmm4/B-rmm heterozygotes, somatic recombination produced rDNAs lacking both the rmm4-associated deletion and the 42-bp deletion. In somatic nuclei in which this rare recombinational event had occurred, all 10(4) copies of nonrecombinant rDNA were eventually replaced by the recombinant rDNA. The results prove that each of the two deletions is the genetic determinant of the observed replication disadvantage. We propose that the analysis of somatically recombinant rDNAs can be used as a general method in locating other mutations which affect rDNA propagation in T. thermophilia. 相似文献