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101.
102.
Sans résuméI. Analyse électrocapillaire des matières colorantes. Rev. gén. Mat. Col. 1926 Vol. 30 pp 34–45II. Phénomènes électrocapillaires et le problème du cancer. Arch. Med. Exper. 1926 Vol. I p 381III. Phénomènes électrocapillaires et l'antagonismes microbiens. Bol. Istituto Sier. Milano 1927 Vol. VI p 313. 相似文献
103.
Book reviewed in this article:
NORTH AND SOUTH AMERICA: The Agricultural and Hunting Methods of the Navaho Indians . W. W. H ill .
NORTH AND SOUTH AMERICA: A Brief History of Navajo Silver smithing . A rthur W oodward .
NORTH AND SOUTH AMERICA: Navaho Life of Yesterday and Today . K atharine L uomala . 相似文献
NORTH AND SOUTH AMERICA: The Agricultural and Hunting Methods of the Navaho Indians . W. W. H ill .
NORTH AND SOUTH AMERICA: A Brief History of Navajo Silver smithing . A rthur W oodward .
NORTH AND SOUTH AMERICA: Navaho Life of Yesterday and Today . K atharine L uomala . 相似文献
104.
J R Davis J F Cortese D A Herrington J R Murphy D F Clyde A W Thomas S Baqar M A Cochran J Thanassi M M Levine 《Experimental parasitology》1992,74(2):159-168
The culture-adapted NF54 isolate of Plasmodium falciparum was subjected in vitro to three sequential limiting dilution titrations and the resulting clone was given the designation CVD1. DNA sequence analysis of the gene encoding the circumsporozoite (CS) protein revealed differences between CVD1 and the published NF54 CS gene. CVD1 had 1191 bp, 397 amino acids, and 42 repeat units while NF54 had 1218 bp, 405 amino acids, and 44 repeat units. The CVD1 clone was more sensitive to chloroquine than was the parental line, in vitro. Anopheles stephensi mosquitoes were infected equally by the cloned and uncloned parasites. Volunteers were readily infected by NF54 and CVD1 following infectious mosquito bites. The availability of a well-characterized, chloroquine-sensitive clone which safety infects humans should facilitate performance of experimental challenge studies to assess vaccine efficacy. 相似文献
105.
106.
Identification of New Genes Involved in the Regulation of Yeast Alcohol Dehydrogenase II 总被引:37,自引:7,他引:30 下载免费PDF全文
Clyde L. Denis 《Genetics》1984,108(4):833-844
Recessive mutations in two negative control elements, CRE1 and CRE2, have been obtained that allow the glucose-repressible alcohol dehydrogenase (ADHII) of yeast to escape repression by glucose. Both the cre1 and cre2 alleles affected ADHII synthesis irrespective of the allele of the positive effector, ADR1. However, for complete derepression of ADHII synthesis, a wild-type ADR1 gene was required. Neither the cre1 nor cre2 alleles affected the expression of several other glucose-repressible enzymes. A third locus, CCR4, was identified by recessive mutations that suppressed the cre1 and cre2 phenotypes. The ccr4 allele blocked the derepression of ADHII and several other glucose-repressible enzymes, indicating that the CCR4 gene is a positive control element. The ccr4 allele had no effect on the repression of ADHII when it was combined with the ADR1-5c allele, whereas the phenotypically similar ccr1 allele, which partially suppresses ADR1-5c, did not suppress the cre1 or cre2 phenotype. Complementation studies also indicated that ccr1 and snf1 are allelic. A model of ADHII regulation is proposed in which both ADR1 and CCR4 are required for ADHII expression. CRE1 and CRE2 negatively control CCR4, whereas CCR1 is required for ADR1 function. 相似文献
107.
In the companion paper (Holmquist et al. 1988), we concluded that there is
no agreement on either the correct branching order or differential rates of
evolution among the higher primates, and we examined in depth why this
uncertainty in the evolutionary understanding of our closest living
relatives persists. Recently, Lake developed two novel methods, based on
group properties of transition and transversion operators, that (a) permit,
in principle, objective resolution of problems of the above type and (b)
attach a statistical significance level to the conclusions drawn. In the
present paper, we develop formulas for using these two methods in tandem
and apply them to study transversion differences in (1) nuclear DNA for a
7-kb segment of the psi eta-globin locus and a 3-kb intergenic region
between the psi beta- and delta- globin loci and (2) mitochondrial DNA for
the 896-bp fragment of Brown et al. Although each of these nucleotide
sequence regions has its characteristic tempo and mode of evolution, the
nuclear and mitochondrial data together, comprising a total of 10,939 base
positions, support a Homo/Pan clade at the 97% confidence level. If we
calibrate the divergence point for humans and chimpanzees at 5 Myr,
consideration of the transversion branch lengths for the combined nuclear
data indicates that the gorilla lineage branched off 600,000- 900,000 years
prior to that, although the 2 sigma sampling errors do not preclude either
a temporal trifurcation for the three species or a considerably more
ancient branch point for the gorilla. To resolve the length of this central
branch to a relative accuracy of 25% and 30% will require a factor of 16
and nine times more data, respectively-- i.e., in excess of 100,000
homologous nucleotides for each of the four primates. For the nuclear
genes, heterogeneity in evolutionary rates between different parts of the
genome is mostly restricted to the human lineage for these two segments.
The lineage leading to chimpanzees has evolved 0.4 (3-kb fragment) to 3.5
(7-kb segment) times as rapidly as the lineage leading to humans, and that
leading to the gorilla has evolved approximately one-fifth to one-half as
rapidly as that leading to chimpanzees. Thus, even local molecular clocks
can "tick" badly. As significant is the fact that virtually contiguous
parts of the genome tick at markedly different rates.(ABSTRACT TRUNCATED AT
400 WORDS)
相似文献
108.
Clyde N. White 《The Western journal of medicine》1915,13(8):330-331
109.
110.
Amy Trentham-Dietz Oguzhan Alagoz Christina Chapman Xuelin Huang Jinani Jayasekera Nicolien T. van Ravesteyn Sandra J. Lee Clyde B. Schechter Jennifer M. Yeh Sylvia K. Plevritis Jeanne S. Mandelblatt for the Breast Working Group of the Cancer Intervention Surveillance Modeling Network 《PLoS computational biology》2021,17(6)
Since 2000, the National Cancer Institute’s Cancer Intervention and Surveillance Modeling Network (CISNET) modeling teams have developed and applied microsimulation and statistical models of breast cancer. Here, we illustrate the use of collaborative breast cancer multilevel systems modeling in CISNET to demonstrate the flexibility of systems modeling to address important clinical and policy-relevant questions. Challenges and opportunities of future systems modeling are also summarized. The 6 CISNET breast cancer models embody the key features of systems modeling by incorporating numerous data sources and reflecting tumor, person, and health system factors that change over time and interact to affect the burden of breast cancer. Multidisciplinary modeling teams have explored alternative representations of breast cancer to reveal insights into breast cancer natural history, including the role of overdiagnosis and race differences in tumor characteristics. The models have been used to compare strategies for improving the balance of benefits and harms of breast cancer screening based on personal risk factors, including age, breast density, polygenic risk, and history of Down syndrome or a history of childhood cancer. The models have also provided evidence to support the delivery of care by simulating outcomes following clinical decisions about breast cancer treatment and estimating the relative impact of screening and treatment on the United States population. The insights provided by the CISNET breast cancer multilevel modeling efforts have informed policy and clinical guidelines. The 20 years of CISNET modeling experience has highlighted opportunities and challenges to expanding the impact of systems modeling. Moving forward, CISNET research will continue to use systems modeling to address cancer control issues, including modeling structural inequities affecting racial disparities in the burden of breast cancer. Future work will also leverage the lessons from team science, expand resource sharing, and foster the careers of early stage modeling scientists to ensure the sustainability of these efforts. 相似文献