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991.
CAG repeat expansion in autosomal dominant pure spastic paraplegia linked to chromosome 2p21-p24 总被引:1,自引:2,他引:1
Nielsen JE; Koefoed P; Abell K; Hasholt L; Eiberg H; Fenger K; Niebuhr E; Sorensen SA 《Human molecular genetics》1997,6(11):1811-1816
CAG repeat expansions have been identified as the disease-causing dynamic
mutations in the coding regions of genes in several dominantly inherited
neurodegenerative disorders, including spinobulbar muscular atrophy,
Huntington's disease, dentatorubral-pallidoluysian atrophy, spinocerebellar
ataxia type 1, 2 and 6 and Machado-Joseph disease. The CAG repeat
expansions are translated to elongated polyglutamine tracts and an
increased size of the polyglutamine tract correlates with anticipation, the
cardinal feature, seen in all these diseases. Autosomal dominant pure
spastic peraplegia (ADPSP) is a degenerative disorder of the central motor
system clinically characterized by slowly progressive and unremitting
spasticity of the legs, hyperreflexia and Babinski's sign. Like the
established CAG repeat diseases ADPSP is characterized by both inter- and
intrafamilial variation and anticipation. Using the Repeat Expansion
Detection (RED) method, we have analyzed 21 affected individuals from six
Danish families with the disease linked to chromosome 2p21-p24. We found
that 20 of 21 affected individuals showed CAG repeat expansions versus two
of 21 healthy spouses, demonstrating a strongly statistically significant
association between the occurrence of the repeat expansion and the disease
(Fisher's test, P < 10(-5)) suggesting that a CAG repeat expansion is
involved presumably as a dynamic mutation in ADPSP linked to chromosome
2p21-p24. The size of the expansion is estimated to be > or = 60 CAG
repeat copies in the affected individuals. The CAG repeat expansion is very
likely translated and expressed as indicated by the detection of a
polyglutamine-containing protein in an ADPSP patient.
相似文献
992.
A newly isolated Pl virulent mutation, vir11, is not suppressed by reb mutations that suppress P1virB mutations. The location of P1virll on the vegetative phage map is at the left-most end, beyond all other known markers. Thus, in the circular prophage, virII may be closely linked to the cl repressor gene. 相似文献
993.
994.
Denoyelle F; Weil D; Maw MA; Wilcox SA; Lench NJ; Allen-Powell DR; Osborn AH; Dahl HH; Middleton A; Houseman MJ; Dode C; Marlin S; Boulila-ElGaied A; Grati M; Ayadi H; BenArab S; Bitoun P; Lina-Granade G; Godet J; Mustapha M; Loiselet J; El-Zir E; Aubois A; Joannard A; Petit C 《Human molecular genetics》1997,6(12):2173-2177
Prelingual non-syndromic (isolated) deafness is the most frequent
hereditary sensory defect. In >80% of the cases, the mode of
transmission is autosomal recessive. To date, 14 loci have been identified
for the recessive forms (DFNB loci). For two of them, DFNB1 and DFNB2, the
genes responsible have been characterized; they encode connexin 26 and
myosin VIIA, respectively. In order to evaluate the extent to which the
connexin 26 gene (Cx26) contributes to prelingual deafness, we searched for
mutations in this gene in 65 affected Caucasian families originating from
various countries, mainly tunisia, France, New Zealand and the UK. Six of
these families are consanguineous, and deafness was shown to be linked to
the DFNB1 locus, 10 are small non consanguineous families in which the
segregation of the trait has been found to be compatible with the
involvement of DFNB1, and in the remaining 49 families no linkage analysis
has been performed. A total of 62 mutant alleles in 39 families were
identified. Therefore, mutations in Cx26 represent a major cause of
recessively inherited prelingual deafness since according to the present
results they would underlie approximately half of the cases. In addition,
one specific mutation, 30delG, accounts for the majority (approximately
70%) of the Cx26 mutant alleles. It is therefore one of the most frequent
disease mutations so far identified. Several lines of evidence indicate
that the high prevalence of the 30delG mutation arises from a mutation hot
spot rather than from a founder effect. Genetic counseling for prelingual
deafness has been so far considerably impaired by the difficulty in
distinguishing genetic and non genetic deafness in families presenting with
a single deaf child. Based on the results presented here, the development
of a simple molecular test could be designed which should be of
considerable help.
相似文献
995.
996.
Bergen AW Haque KA Qi Y Beerman MB Garcia-Closas M Rothman N Chanock SJ 《Human mutation》2005,26(3):262-270
The promise of whole genome amplification (WGA) is that genomic DNA (gDNA) quantity will not limit molecular genetic analyses. Multiple displacement amplification (MDA) and the OmniPlex PCR-based WGA protocols were evaluated using 4 and 5 ng of input gDNA from 60 gDNA samples from three tissue sources (mouthwash, buffy coat, and lymphoblast). WGA DNA (wgaDNA) yield and genotyping performance were evaluated using genotypes determined from gDNA and wgaDNA using the AmpFlSTR Identifiler assay and N = 49 TaqMan SNP assays. Short tandem repeat (STR) and SNP genotyping completion and concordance rates were significantly reduced with wgaDNA from all WGA methods compared with gDNA. OmniPlex wgaDNA exhibited a greater reduction in genotyping performance than MDA wgaDNA. Reduced wgaDNA genotyping performance was due to allelic (all protocols) and locus (OmniPlex) amplification bias leading to heterozygote and locus dropout, respectively, and %GC sequence content (%GC) was significantly correlated with TaqMan assay performance. Lymphoblast wgaDNA exhibited higher yield (OmniPlex), buffy coat wgaDNA exhibited higher STR genotyping completion (MDA), whereas mouthwash wgaDNA exhibited higher SNP genotyping discordance (MDA). Genotyping of wgaDNA generated from < or = 5 ng gDNA, e.g., from archaeological, forensic, prenatal diagnostic, or pathology samples, may require additional genotyping validation with gDNA and/or more sophisticated analysis of genotypes incorporating observed reductions in genotyping performance. 相似文献
997.
Wendy Cozen Mulugeta Gebregziabher David V Conti David J Van Den Berg Gerhard A Coetzee Sophia S Wang Nathaniel Rothman Leslie Bernstein Patricia Hartge Ann Morhbacher Simon G Coetzee Muhammad T Salam Wei Wang John Zadnick Sue A Ingles 《Cancer epidemiology, biomarkers & prevention》2006,15(11):2285-2291
Interleukin-6 (IL-6) promotes normal plasma cell development and proliferation of myeloma cells in culture. We evaluated IL-6 genotypes and body mass index (BMI) in a case-control study of multiple myeloma and plasmacytoma. DNA samples and questionnaires were obtained from incident cases of multiple myeloma (n = 134) and plasmacytoma (n = 16; plasma cell neoplasms) ascertained from the Los Angeles County population-based cancer registry and from siblings or cousins of cases (family controls, n = 112) and population controls (n = 126). Genotypes evaluated included IL-6 promoter gene single nucleotide polymorphisms (SNP) at positions -174, -572, and -597; one variable number of tandem repeats (-373 A(n)T(n)); and one SNP in the IL-6 receptor (IL-6ralpha) gene at position -358. The variant allele of the IL-6 promoter SNP -572 was associated with a roughly 2-fold increased risk of plasma cell neoplasms when cases were compared with family [odds ratio (OR), 1.8; 95% confidence interval (95% CI), 0.7-4.7] or population controls (OR, 2.4; 95% CI, 1.2-4.7). The -373 9A/9A genotype was associated with a decreased risk compared with the most common genotype (OR for cases versus family controls, 0.4; 95% CI, 0.1-1.7; OR for cases versus population controls, 0.3; 95% CI, 0.1-0.9). No other SNPs were associated with risk. Obesity (BMI >or= 30 kg/m(2)) increased risk nonsignificantly by 40% and 80% when cases were compared with family controls or population controls, respectively, relative to persons with a BMI of <25 kg/m(2). These results suggest that IL-6 promoter genotypes may be associated with increased risk of plasma cell neoplasms. 相似文献
998.
Impact of misclassification in genotype-exposure interaction studies: example of N-acetyltransferase 2 (NAT2), smoking, and bladder cancer. 总被引:1,自引:0,他引:1
Anne C Deitz Nathanial Rothman Timothy R Rebbeck Richard B Hayes Wong-Ho Chow Wei Zheng David W Hein Montserrat García-Closas 《Cancer epidemiology, biomarkers & prevention》2004,13(9):1543-1546
Errors in genotype determination can lead to bias in the estimation of genotype effects and gene-environment interactions and increases in the sample size required for molecular epidemiologic studies. We evaluated the effect of genotype misclassification on odds ratio estimates and sample size requirements for a study of NAT2 acetylation status, smoking, and bladder cancer risk. Errors in the assignment of NAT2 acetylation status by a commonly used 3-single nucleotide polymorphism (SNP) genotyping assay, compared with an 11-SNP assay, were relatively small (sensitivity of 94% and specificity of 100%) and resulted in only slight biases of the interaction parameters. However, use of the 11-SNP assay resulted in a substantial decrease in sample size needs to detect a previously reported NAT2-smoking interaction for bladder cancer: 1,121 cases instead of 1,444 cases, assuming a 1:1 case-control ratio. This example illustrates how reducing genotype misclassification can result in substantial decreases in sample size requirements and possibly substantial decreases in the cost of studies to evaluate interactions. 相似文献
999.
Delayed vascular injury after revision total hip arthroplasty is a rare and unusual complication. We report a case of a mechanical complication in which migration of a constraining ring locking mechanism used during a revision total hip arthroplasty caused a pseudoaneurysm of the common femoral artery. 相似文献
1000.
Robert E. Tarone Michael C. R. Alavanja Shelia Hoar Zahm Jay H. Lubin Dale P. Sandler Suzanne B. McMaster Nathaniel Rothman Aaron Blair 《American journal of industrial medicine》1997,31(2):233-242
Response rates were examined in a prospective epidemiologic study of individuals, mostly farmers, from Iowa and North Carolina seeking a pesticide applicator license during the period from 1994 through 1996. In the first year of enrollment 16,535 farmers (representing 77% of eligible farmer applicators) enrolled in the study by completing a 17-page questionnaire administered at a pesticide training session; 47% of the enrolled farmers completed and returned a much longer take-home questionnaire. The characteristics of farmers who completed only the enrollment questionnaire were quite similar to those of farmers who also completed and returned the take-home questionnaire. The most notable difference was the increased age of responders. Thus, the study population might have slightly higher cumulative farm exposures and slightly lower current farm exposures than the base population of all farmer applicators. The lack of evidence for substantial selection bias is reassuring for the Agricultural Health Study, and provides a measure of reassurance for other studies depending on the voluntary completion of self-administered questionnaires. Am. J. Ind. Med. 31:233–242, 1997. (This article is a US Government work and, as such, is in the public domain of the United States of America.) © 1997 Wiley-Liss, Inc. 相似文献