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71.
Jihai Xu Jing Wu Xiaofeng Teng Libing Cai Huizong Yuan Xiaokun Chen Mu Hu Xin Wang Ning Jiang Hong Chen 《American journal of medical genetics. Part A》2020,182(9):2117-2123
Polydactyly and syndactyly are digital abnormalities in limb‐associated birth defects usually caused by genetic disorders. In this study, a five‐generation Chinese pedigree was found with triphalangeal thumb polysyndactyly syndrome (TPTPS), showing an autosomal dominant pattern of inheritance. We utilized linkage analysis and whole genome sequencing (WGS) for the genetic diagnosis of this pedigree. Linkage analysis was performed using a genome‐wide single nucleotide polymorphism (SNP) chip and three genomic regions were identified in chromosomes 2, 6, and 7 with significant linkage signals. WGS discovered a copy number variation (CNV) mutation caused by a large duplication region at the tail of chromosome 7 located in exons 1–5 of the LMBR1 gene, including the zone of polarizing activity regulatory sequence (ZRS), with a length of approximately 180 kb. A real‐time polymerase chain reaction (PCR) assay confirmed the duplication. The findings of our study supported the notion that large duplications including the ZRS caused TPTPS. Our study showed that linkage analysis in combination with WGS could successfully identify the disease locus and causative mutation in TPTPS, which could help elucidate the molecular mechanisms and genotype–phenotype correlations in polydactyly. 相似文献
72.
Point mutation of the BRAF gene is a common genetic event in papillary thyroid carcinomas. More recently, it has been found that BRAF can also participate in chromosomal rearrangement. In this study, we explore yet another possible mechanism of BRAF alteration, which involves copy number gain. Using fluorescence in situ hybridization with BRAF specific and chromosome 7 centromeric probes, we studied 62 follicular thyroid tumors and 32 papillary carcinomas. We found
that numerical changes in BRAF copy number were rare in papillary thyroid carcinomas, while they occurred in 16–45% of follicular tumors of conventional
and oncocytic (Hürthle cell) types. They were due to amplification of the gene or gain of one or more copies of chromosome
7. Tetrasomy for chromosome 7 was overall the most common finding. The changes in BRAF copy number did not overlap with RAS mutations in follicular tumors. In a group of follicular carcinomas, tumors with BRAF copy number gain were significantly more often widely invasive (67%) compared to tumors with no copy number change (18%).
By Western blotting, the tumors carrying four copies of the gene revealed higher expression of BRAF protein, suggesting that
copy number gain may represent another mechanism of BRAF activation in thyroid tumors. 相似文献
73.
Analysis of the HIV-1 V3 quasispecies present in an individual at the time of seroconversion was carried out. The polymerase chain reaction (PCR) was used to amplify proviral HIV-1 DNA extracted from peripheral blood mononuclear cells from a patient who was viraemic (p24 = 15 pg/ml) and had an equivocal HIV-1 antibody status. The PCR products were cloned and the DNA sequence determined for 15 clones. These data showed that the V3 region contained only limited sequence heterogeneity with a major variant accounting for 66% of the protein quasispecies present. The protein sequence of the principal neutralising domain on all species contained the relatively rare GPGKTL motif rather than GPGRAF. The relevance of these data for early stages of HIV infection are discussed. 相似文献
74.
Chia-Chi Ku Chwan-Chuen King Ching-Yuang Lin Huei-Chu Hsu Li-Yen Chen Yi-Yuen Yueh Gwong-Jen J. Chang 《Journal of medical virology》1994,44(2):122-131
Because 21 immunized children (13%) among the 162 confirmed Japanese encephalitis (JE) cases during 1986–1991 occurred in Taiwan, we collected 320 serum samples from Taiwan children aged 15–31 and 27–44 months immediately before the 1st dose (n = 41) and 1–3 months after the 2nd dose (n = 78, 27 pairs), and immediately before (n = 58) and 1–3 months after the 3rd dose (n = 143,44 pairs) to determine neutralization antibody (Nt Ab) against the Nakayama (N) and Beijing-1 (B) strains and two Taiwan wild type JE viruses (JEV): CC-27 and CH-1392. Our Nt results showed that (1) B vaccine stimulated a better homologous Ab response than N vaccine for Nt Ab seropositivity rate (NASR), produced a higher level of Nt titer after the primary immunization [2 doses = 100% vs. 91%, geometric mean titer (GMT) = 115 vs. 22], had a greater booster effect (3 doses: 100% vs. 95%; GMT = 320 vs. 33), and showed a better capability to neutralize two local Taiwan JEV strains, particularly only after 3 doses (ave. NASR for B vs. N = 90% vs. 10%; and GMT for B vs. N = 154 vs. 1); (2) the two wild type JEV strains had different plaque morphology and antigenic variation and the CC-27 strain was not neutralized as well as the CH-1392 strain after 3 doses of vaccine (BBB or NNN or NNB); and (3) 30% of the children had lost JEV Nt Ab one year after the 2nd dose of N vaccine and natural infection with JE virus did occur among those children after immunization. In conclusion, (1) three doses of mouse-brain vaccine are the minimum requirement to protect children against the local Taiwan JEV; (2) the best strain for a JE vaccine depends on level of Nt Ab it induced, the molecular epidemiology and antigenic variation of the JEV in each local area; and (3) future vaccine must produce better B- and T-cell memory. © 1994 Wiley-Liss, Inc. 相似文献
75.
I. M. Rodionov V. N. Yarygin Kh. M. Markov V. G. Pinelis F. K. Lakgueva O. S. Tarasova I. A. Sokolova T. P. Storozhevykh V. B. Koshelev 《Bulletin of experimental biology and medicine》1989,108(5):1651-1653
Department of Physiology of Man and Animals, Faculty of Biology, Moscow University. Laboratory of Pathophysiology, Research Institue of Pediatrics, Academy of Medical Sciences of the USSR. Department of General Biology, N. I. Pirogov Second Moscow Medical Institute. (Presented by Academician of the Academy of Medical Sciences of the USSR M. Ya. Studenikin.) Translated from Byullet en' Éksperimental'noi Biologii i Meditsiny, Vol. 108, No. 11, pp. 620–622, November, 1989. 相似文献
76.
Mattick C Dewin D Polley S Sevilla-Reyes E Pignatelli S Rawlinson W Wilkinson G Dal Monte P Gompels UA 《Virology》2004,318(2):582-597
Previously, we identified the glycoprotein gO gene, UL74, as a hypervariable locus in the human cytomegalovirus (HCMV) genome [Virology 293 (2002) 281]. Here, we analyze gO from 50 isolates from congenitally infected newborns, transplant recipients, and HIV/AIDS patients from Italy, Australia, and UK. These are compared to four gO groups described from USA transplantation patients [J. Virol. 76 (2002) 10841]. Phylogenetic analyses identified seven genotypes. Divergence between genotypes was up to 55% and within 3%. Discrete linkage was shown between seven hypervariable gO and gN genotypes, but not with gB. This suggests interactions, while gN and gO are known to form complexes with distinct conserved glycoproteins gM, gH/gL, respectively, both are involved in fusogenic entry and exit. Codon-based maximum likelihood models showed evidence for sites of positive selection. Further analyses of disease relationships should take into account these newly defined gO/gN groups. 相似文献
77.
A second group of hepatitis C viruses 总被引:7,自引:0,他引:7
Kyoko Tsukiyama-Kohara Michinori Kohara Kenjiro Yamaguchi Noboru Maki Ayumi Toyoshima Keizaburo Miki Satoshi Tanaka Nobu Hattori Akio Nomoto 《Virus genes》1991,5(3):243-254
cDNA clone 11–7 was isolated by immunoscreening a cDNA library that was prepared from a pooled plasma of non-A non-B hepatitis (NANBH) patients using expression vector gt 11. This cDNA corresponds to known nucleotide positions 3983–4745 of the genome of hepatitis C virus (HCV). This clone was used as a probe for screening the HCV-related cDNAs in a cDNA library similarly prepared by using gt 10. As a result, six more cDNA clones were isolated and analyzed for their nucleotide sequences. The results strongly suggested that there are at least two groups of HCV, group I and group II. According to our classification, the prototype HCV and clone 11–7 belong to group I HCV, and their nucleotide and deduced amino acid sequences were diverged from those of group II HCV. Genetic variation observed in the nucleotide and the amino acid sequences between the two groups resembles that in the NS3 region of the genome between Japanese encephalitis virus and West Nile fever virus. Polypeptides produced inEscherichia coli carrying a clone 11–7 or a group II cDNA clone E reacted with antibodies in the blood of 12 or 4 out of 14 individual chronic NANBH patients, respectively. Our data clearly indicate the existence of a second group of HCV. 相似文献
78.
CORTICAL SLOW POTENTIAL CHANGES IN MAN RELATED TO INTERSTIMULUS INTERVAL AND TO PRE TRIAL PREDICTION OF INTERSTIMULUS INTERVAL 总被引:1,自引:0,他引:1
Two experiments were performed to explore further the relationship between the cortical slow potential change known as the “contingent negative variation” (CNV) and the concept of “expectancy.” In Experiment I, 24 male Ss were presented click pairs, with inter-click intervals of 800, 1600 and 4800 msec (2 blocks of 10 trials each, counterbalanced between Ss for order), and instructed to press a key after the second click. Interval by order by trials analysis of variance showed interval to be the only significant factor: CNVs were lower and RTs longer as interval increased. In Experiment II, 8 female Ss given 60 pairs of clicks, 30 each with separations of 1200 and 2400 msec, were instructed to respond as in Experiment I, and were asked to make a pretrial prediction of the interval they would next receive. Analysis of variance of RTs showed that Ss responded slower when the interval was other than that predicted. Prediction by reception by subjects analysis of variance of CNV amplitude at the 1200 msec point gave a significant F only for prediction, mean amplitude for short being higher than for long. A similar design applied to CNV amplitudes at both the 1200 and 2400 msec points when Ss received the long interval yielded a significant measurement point by interval predicted interaction; at the 1200 msec point, short predictions were followed by higher CNVs than were long predictions; at 2400 msec, the opposite was found. These data combine with those already in the literature to indicate that the relationship between “expectancy” and the CNV is far from simple, and that cognitive and motivational factors play a significant role in determining CNV amplitude. 相似文献
79.
Genetics of the low density lipoprotein receptor: 总被引:1,自引:0,他引:1
Fibroblast association (plasma membrane binding plus intracellular accumulation) and degradation of radioiodinated low density lipoprotein (125I-LDL) index plasma membrane LDL receptor activity. Cultured fibroblasts from 23 subjects affected with familial hypercholesterolemia (HC) and from 95 subjects without HC (non-HCs) were tested for 125I-LDL association and degradation. Both LDL receptor activity indices were twice as high in non-HC and HC heterozygous cell strains. This is compatible with a major gene effect on LDL receptor activity. However, a considerable overlap between non-HC and HC heterozygous values was found in the 125I-LDL association assay [median (range) 970 (330-2500), and 450 (250-490), respectively] and in the degradation assay [median (range) 810 (280-2020), and 470 (160-790), respectively]. The values are expressed as ng 125I-LDL X mg cell protein-1 X 4.5 h-1. These great overlaps in the LDL receptor activity indices support the view that the influence of LDL receptor activity on the HC phenotype may be smaller than believed previously. Furthermore, for the diagnosis of HC, these LDL receptor activity assays are far more expensive and have less sensitivity and specificity than simple serum cholesterol determination. The LDL receptor-dependent 125I-LDL association values for the HC heterozygous individuals clustered into four groups. Family data supported the hypothesis that this variation could be due to four different LDL receptor variants, each coded for by different alleles at the LDL receptor locus. If confirmed, this finding may have implications for the understanding of the variable expression of HC and also of the genetic impact on lipoprotein metabolism and susceptibility to atherosclerosis in non-HCs. 相似文献
80.
Satoru Honma Akinari Tokiyoshi Katsushi Kawai Masahiro Koizumi Kodo Kodama 《Anatomical science international / Japanese Association of Anatomists》2008,83(4):232-238
A radial artery running beneath the biceps tendon was found in the cadaver of a Japanese woman during a student dissection
course at Kumamoto University School of Medicine in 2006. The brachial artery bifurcated into the radial artery and the ulnar
artery in the cubital fossa, and the radial artery twisted laterally running beneath the biceps tendon, and when it was situated
laterally to the tendon, twisted distally at the level of the radial tuberosity, and then twisted medially again. After the
radial artery passed over the biceps tendon, it turned distally and continued as a normal radial artery. The superficial brachial
artery, which coexisted with the brachial artery, was given off from the axillary artery and it continued to the final twist
of the radial artery. The course of this radial artery is similar to the arterial rings surrounding the biceps tendon, found
during the same dissection course. The arterial rings were formed between the brachial artery and the radial artery, and their
proximal origins ran beneath the biceps tendon, while the distal origins were superficial. The present arterial variation
is thought to have occurred when the normal part of the radial artery in the cubital fossa was substituted by the arterial
ring, coexisting with the superficial brachial artery, which usually disappears during normal development. Furthermore, it
is suggested that a part of the arterial ring always remains as a radial recurrent artery. 相似文献