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71.
One hundred twenty-two patients with various colon pathologies (43 colorectal carcinoma patients exclusive of the known autosomal dominant colorectal cancer syndromes, 31 patients with solitary colorectal adenomas, 27 patients with ulcerative colitis, and 21 controls with no evidence of colorectal cancer) were investigated for in vitro tetraploidy in dermal fibroblasts cultures using a metaphase assay for determination of numerical chromosomal alterations. Later, stationary cultures of these skin fibroblasts were investigated with DNA flow cytometry. There was good correlation between the percentage of tetraploid metaphase cells and the percentage of nuclei with a flow cytometric DNA index of 2. Using a linear discrimination function to classify the flow cytometric data, the peak with DNA index of 2 was the most important parameter, supplemented by the region with DNA index greater than 2, whereas the region with DNA index between 1 and 2 probably represented a different subpopulation. We have thus demonstrated that only the region with a DNA index of 2 or greater is suitable in determining in vitro tetraploidy in stationary skin fibroblast cultures. 相似文献
72.
73.
Alignment of the restriction map of mouse adenovirus FL with that of human adenovirus 2 总被引:8,自引:0,他引:8
A detailed restriction map of mouse adenovirus (AdFL) has been constructed based on sites of cleavage of AdFL DNA by 19 restriction endonucleases. The AdFL map has been oriented with that of human adenovirus 2 (Ad2) by identifying which end of AdFL DNA is retained in virus particles with incomplete genomes compared with the end retained by Ad2 defective particles (C. Tibbetts, 1977, Cell12, 243–249). The two maps were also oriented by cross-hybridization tests with a series of restriction fragments of each viral DNA. The latter experiments revealed two regions of homology between Ad2 and AdFL DNA, corresponding to the positions of the Ad2 hexon gene and an Ad2 hexon-associated protein gene. 相似文献
74.
Comparison of Real-Time, Quantitative PCR with Molecular Beacons to Nested PCR and Culture Methods for Detection of Mycobacterium avium subsp. paratuberculosis in Bovine Fecal Samples 下载免费PDF全文
Ying Fang Wai-Hong Wu Jessica L. Pepper Jill L. Larsen Salvatore A. E. Marras Eric. A. Nelson William B. Epperson Jane Christopher-Hennings 《Journal of clinical microbiology》2002,40(1):287-291
An automated PCR with fluorescent probes (molecular beacons) detected Mycobacterium avium subsp. paratuberculosis in bovine feces. When the PCR was compared with culture in testing 41 fecal samples, kappa scores of 0.94 to 0.96, a sensitivity of 93 to 96%, and a specificity of 92% were obtained. Results were quantitated by using a standard curve derived from a plasmid containing IS900. A minimum quantity of 1.7 x 10(-4) pg of DNA, correlating to 1 to 8 CFU, was detected. 相似文献
75.
Kristiansen OP Karlsen AE Larsen ZM Johannesen J Pociot F Mandrup-Poulsen T;Danish IDDM Epidemiology Genetics Group Danish Study Group of IDDM in Childhood 《Scandinavian journal of immunology》2004,59(6):582-591
CD4 is a candidate gene in autoimmune diseases, including Type 1 diabetes mellitus (T1DM), because the CD4 receptor is crucial for appropriate antigen responses of CD4(+) T cells. We previously found linkage between a CD4-1188(TTTTC)(5-14) promoter polymorphism and T1DM. In the present study, we screened the human CD4 promoter for mutations and identified three frequent single nucleotide polymorphisms (SNPs): CD4-181C/G, CD4-521C/G and CD4-1050T/C. The SNPs are in strong linkage disequilibrium (LD) and association with the CD4-1188(TTTTC)(5-14) alleles, and we observed nine CD4 promoter haplotypes, of which four are frequent. We genotyped the SNPs in 253 Danish T1DM families (1129 individuals) and found evidence for linkage and association of a CD4 (A4(-1188)T(-1050)G(-521)C(-181)) haplotype to T1DM. In reporter studies, we show that (1) the T1DM-associated CD4 haplotype encodes high constitutive promoter activity and (2) the CD4-181G variant encodes higher stimulated promoter activity than the CD4-181C variant. This difference is in part neutralized in the frequently occurring CD4 promoter haplotypes by the more upstream genetic variants. Thus, we report functional impact of a novel CD4-181C/G SNP on stimulated CD4 promoter activity and the identification of a novel CD4 haplotype with high constitutive promoter activity that is linked and associated with T1DM. 相似文献
76.
Pernille Mathiesen Tørring Martin Jakob Larsen Charlotte Brasch-Andersen Lotte Nylandsted Krogh Maria Kibæk Lone Laulund Niels Illum Ulrike Dunkhase-Heinl Antje Wiesener Bernt Popp Giuseppe Marangi Tina Duelund Hjortshøj Jakob Ek Ida Vogel Naja Becher Laura Roos Marcella Zollino Christina Ringmann Fagerberg 《European journal of medical genetics》2019,62(2):129-136
Introduction
MED13L-related intellectual disability is characterized by moderate intellectual disability (ID), speech impairment, and dysmorphic facial features. We present 8 patients with MED13L-related intellectual disability and review the literature for phenotypical and genetic aspects of previously described patients.Materials and methods
In the search for genetic aberrations in individuals with ID, two of the patients were identified by chromosomal microarray analysis, and five by exome sequencing. One of the individuals, suspected of MED13L-related intellectual disability, based on clinical features, was identified by Sanger sequencing.Results
All 8 individuals had de novo MED13L aberrations, including two intragenic microdeletions, two frameshift, three nonsense variants, and one missense variant. Phenotypically, they all had intellectual disability, speech and motor delay, and features of the mouth (open mouth appearance, macroglossia, and/or macrostomia). Two individuals were diagnosed with autism, and one had autistic features. One had complex congenital heart defect, and one had persistent foramen ovale. The literature was reviewed with respect to clinical and dysmorphic features, and genetic aberrations.Conclusions
Even if most clinical features of MED13L-related intellectual disability are rather non-specific, the syndrome may be suspected in some individuals based on the association of developmental delay, speech impairment, bulbous nasal tip, and macroglossia, macrostomia, or open mouth appearance. 相似文献77.
Gerdes T Kirchhoff M Lind AM Larsen GV Schwartz M Lundsteen C 《European journal of human genetics : EJHG》2005,13(2):171-175
In routine prenatal diagnostics we used a commercial multiplex ligation-dependent probe amplification (MLPA) kit for aneuploidy screening for chromosomes 13, 18, 21, X and Y. We present the results of 1593 consecutive prenatal samples analysed and diagnosed prior to knowledge of the G-banding analysis during 8-month routine use of computer-assisted MLPA aneuploidy screening. In total, 27 aneuploidies were detected. There were no false positive results while two false negative results could be explained by a placental mosaicism and a partial monosomy, respectively. In total, 3.2% of the samples were inconclusive. We conclude that automatic computer assisted MLPA is a rapid, simple and reliable method for detection of aneuploidies in prenatal diagnostics. 相似文献
78.
Andreo Larsen 《Acta physiologica (Oxford, England)》1978,102(1):35-40
The effects of pindolol and sotalol on neuromuscular transmission were tested using intracellular micro-electrode recording of resting membrane potentials, miniature end-plate potentials and end-plate potentials, and recording of muscle contractions upon nerve stimulation of rat phrenic nerve-hemidiaphragm preparations. Both pindolol and sotalol reduced the amplitudes of miniature end-plate potentials and end-plate potentials in a dose-dependent manner without significantly affecting their time-courses. Pindolol, but not sotalol, also increased the frequency of the miniature end-plate potentials and decreased the number of acetylcholine quanta released by nerve impulses. Neither of the drugs significantly affected resting membrane potentials of the muscle fibres or excitability of the motor nerve to electric stimulation. 相似文献
79.
Juhani Juntunen Heikki Teräväinen Kalervo Eriksson Andreo Larsen Matti Hillbom 《Virchows Archiv : an international journal of pathology》1979,383(3):241-252
Summary The effects of variable dietary thiamine concentrations (deficient, normal, surplus) on the development of alcoholic neuromyopathy in rats exposed for 36 weeks to 10–25% (v/v) ethanol or water (control group) as the sole drinking fluid were studied by histological and electrophysiological methods.Abnormalities in the structure of the sciatic nerve (phagocytosis, myelin abnormalities, increase in nonspecific cholinesterase activity) and tibial muscles (angular atrophic fibers, group atrophy, fibre necrosis) developed more frequently in animals on diets deficient in thiamine than in animals on diets with normal or surplus thiamine, and more frequently in animals drinking alcohol and water than in those drinking water alone. No differences were observed between the different groups in the number of perivascular sympathetic nerves, in the motor nerve conduction velocities and in the muscle fibrillation potentials.Thus, thiamine deficiency, established as a significant reduction of red blood cell transketolase activity, seems to have a deleterious effect on the peripheral nerves and muscles. The effect is enhanced by the simultaneous consumption of ethyl alcohol. 相似文献
80.
Kulesh DA Loveless BM Norwood D Garrison J Whitehouse CA Hartmann C Mucker E Miller D Wasieloski LP Huggins J Huhn G Miser LL Imig C Martinez M Larsen T Rossi CA Ludwig GV 《Laboratory investigation; a journal of technical methods and pathology》2004,84(9):1200-1208
During the summer of 2003, an outbreak of human monkeypox occurred in the Midwest region of the United States. In all, 52 rodents suspected of being infected with monkeypox virus were collected from an exotic pet dealer and from private homes. The rodents were euthanized and submitted for testing to the United States Army Medical Research Institute of Infectious Diseases by the Galesburg Animal Disease Laboratory, Illinois Department of Agriculture. The rodent tissue samples were appropriately processed and then tested by using an integrated approach involving real-time polymerase chain reaction (PCR) assays, an antigen-detection immunoassay, and virus culture. We designed and extensively tested two specific real-time PCR assays for rapidly detecting monkeypox virus DNA using the Vaccinia virus F3L and N3R genes as targets. The assays were validated against panels of orthopox viral and miscellaneous bacterial DNAs. A pan-orthopox electrochemiluminescence (ECL) assay was used to further confirm the presence of Orthopoxvirus infection of the rodents. Seven of 12 (58%) animals (seven of 52 (15%) of all animals) tested positive in both monkeypox-specific PCR assays and two additional pan-orthopox PCR assays (in at least one tissue). The ECL results showed varying degrees of agreement with PCR. One hamster and three gerbils were positive by both PCR and ECL for all tissues tested. In addition, we attempted to verify the presence of monkeypox virus by culture on multiple cell lines, by immunohistology, and by electron microscopy, with negative results. Sequencing the PCR products from the samples indicated 100% identity with monkeypox virus strain Zaire-96-I-16 (a human isolate from the Congo). These real-time PCR and ECL assays represent a significant addition to the battery of tests for the detection of various orthopoxviruses. In light of the recent monkeypox virus transmissions, early detection of the virus is crucial for both natural outbreaks and potential acts of bioterrorism. 相似文献