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排序方式: 共有3327条查询结果,搜索用时 15 毫秒
51.
Aikaterini Nanou Chrisavgi Toumpeki Pavlos Fanis Nicoletta Bianchi Lucia Carmela Cosenza Cristina Zuccato George Sentis Giorgos Giagkas Coralea Stephanou Marios Phylactides Soteroula Christou Michalis Hadjigavriel Maria Sitarou Carsten W. Lederer Roberto Gambari Marina Kleanthous Eleni Katsantoni 《Haematologica》2021,106(4):1207
52.
Carfora Vincenzo Spiniello Giorgio Ricciolino Riccardo Di Mauro Marco Migliaccio Marco Giuseppe Mottola Filiberto Fausto Verde Nicoletta Coppola Nicola 《Journal of thrombosis and thrombolysis》2021,51(3):642-648
Journal of Thrombosis and Thrombolysis - The actual Coronavirus Disease (COVID 19) pandemic is due to Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), a member of the coronavirus... 相似文献
53.
Cloning of the gene encoding the delta subunit of the human T-cell receptor reveals its physical organization within the alpha-subunit locus and its involvement in chromosome translocations in T-cell malignancy. 总被引:10,自引:5,他引:10 下载免费PDF全文
M Isobe G Russo F G Haluska C M Croce 《Proceedings of the National Academy of Sciences of the United States of America》1988,85(11):3933-3937
By taking advantage of "chromosomal walking" techniques, we have obtained clones that encompass the T-cell receptor (TCR) delta-chain gene. We analyzed clones spanning the entire J alpha region extending 115 kilobases 5' of the TCR alpha-chain constant region and have shown that the TCR delta-chain gene is located over 80 kilobases 5' of C alpha. TCR delta-chain gene is rearranged in the gamma/delta-expressing T-cell line Peer and is deleted in alpha/beta-expressing T-cell lines. Sequence analysis of portions of this genomic region demonstrates its identity with previously described cDNA clones corresponding to the C delta and J delta segments. Furthermore, we have analyzed a t(8;14)-(q24;q11) chromosome translocation from a T-cell leukemia and have shown that the J delta segment is rearranged in cells deriving from this tumor and probably directly involved in the translocation. Thus, the newly cloned TCR delta chain is implicated in the genesis of chromosome translocations in T-cell malignancies carrying cytogenetic abnormalities of band 14q11. 相似文献
54.
Piero Olliaro Luciano Lombardi Simona Frigerio Nicoletta Basilico Donatella Taramelli Diego Monti 《Ultrastructural pathology》2013,37(1):9-13
Hemozoin, the detoxification product of hemoglobin heme, piles up as electron-dense material in the food vacuole (FV) of intraerythrocytic malaria parasites (malaria pigment). In infected individuals, pigment is internalized by both circulating and resident phagocytes, thus modulating their functions. Synthetic beta-hematin, prepared in vitro from hematin (ferriprotoporphyrin IX hydroxide) in acidic condition, is spectroscopically identical to hemozoin. In this electron microscopy study, native and synthetic hemozoin also prove to be morphologically indistinguishable (large polygonal crystals with apparent transverse banding) and to undergo the same process when internalized by phagocytes (primarily a direct uptake of crystals, similar to what is described for asbestos fibers). On the contrary,whole parasites appear to follow a classical endocytic pathway. This suggests that there may be differences between the ingestion of free particles and whole parasites in terms of modulation of phagocytes' functions. 相似文献
55.
Daniele Recupero Lorenzo Daniele Caterina Marchiò Luca Molinaro Isabella Castellano Paola Cassoni Alberto Righi Filippo Montemurro Piero Sismondi Nicoletta Biglia Giuseppe Viale Mauro Risio Anna Sapino 《The Journal of pathology》2013,229(3):390-399
A subgroup of HER2‐overexpressing breast tumours co‐expresses p95 $^{{\rm{HER2}}}$ , a truncated HER2 receptor that retains a functional HER2 kinase domain but lacks the extracellular domain, thus impairing trastuzumab binding. We evaluated p95 $^{{\rm{HER2}}}$ expression in 99 frozen breast carcinoma samples by western blot analysis. The HER2‐positive cell line BT474 treated with pervanadate or pronase was used as a positive control for p95 $^{{\rm{HER2}}}$ expression. Immunohistochemistry was performed on parallel formalin‐fixed, paraffin‐embedded sections of the same case series using antibodies directed against either the intra‐ or extra‐cellular binding domain of HER2. In particular, biotinylated trastuzumab (BiotHER) was used to evaluate the binding capacity of the humanized antibody. To avoid a subjective evaluation of the score values and the percentage of immunostained cells, the slides were scanned and automatically analysed. The number of cases with HER2 overexpression (score 3+) and HER2 gene amplification was higher in the p185 $^{{\rm{HER2}}}$ ‐positive/p95 $^{{\rm{HER2}}}$ ‐positive samples than in the p185 $^{{\rm{HER2}}}$ ‐positive/p95 $^{{\rm{HER2}}}$ ‐negative group. Automated analysis confirmed a significantly higher percentage of 3+ scored cells in p95 $^{{\rm{HER2}}}$ ‐positive cases. Conversely, the percentage of 2+ scored cells was higher in p95 $^{{\rm{HER2}}}$ ‐negative cases. The status of the HER2 extracellular domain was then studied using flow cytometry on BT474 cells after pronase enzymatic digestion using trastuzumab and pertuzumab, while the presence of HER2‐HER3 dimers was studied using a proximity‐ligation assay. In vitro experiments showed that short‐term pronase digestion of BT474 cells produced two HER2 fragments (of 95 and 150 kDa, detectable in tissue specimens as well), increased the binding affinity of trastuzumab, reduced the rate of HER2–HER3 dimers, and did not interfere with pertuzumab‐binding capacity. In conclusion, the presence of p95 $^{{\rm{HER2}}}$ as detected by western blot analysis does not compromise the immunohistochemical detection of HER2. Our data suggest that a reduction of the receptor steric hindrance as induced by enzymatic shedding may facilitate the binding capacity of trastuzumab. Copyright © 2012 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd. 相似文献
56.
Venusia Cortellini Andrea Verzeletti Nicoletta Cerri Alberto Marino Francesco De Ferrari 《Croatian medical journal》2013,54(3):279-285
Aim
To find an association between Y chromosome polymorphisms and some ethnic groups.Methods
Short tandem repeats (STR) and single-nucleotide polymorphisms (SNP) on the Y chromosome were typed in 311 unrelated men from four different ethnic groups – Italians from northern Italy, Albanians, Africans from the Maghreb region, and Indo-Pakistanis, using the AmpFlSTR® Yfiler PCR Amplification Kit and the SNaPshot Multiplex Kit.Results
STRs analysis found 299 different haplotypes and SNPs analysis 11 different haplogroups. Haplotypes and haplogroups were analyzed and compared between different ethnic groups. Significant differences were found among all the population groups, except between Italians and Indo-Pakistanis and between Albanians and Indo-Pakistanis.Conclusions
Typing both STRs and SNPs on the Y chromosome could become useful in determining ethnic origin of a potential suspect.Determining the ethnic origin of a suspect through DNA analysis of biological stains left at the crime scene is an important part of criminal investigations. To discriminate between different ethnic groups, short tandem repeat (STR) autosomal marker analysis (1-6) can be complemented by single-nucleotide polymorphism (SNP) assays, which have have been demonstrated to be more useful for this purpose (7,8). The introduction of new markers, mostly from the Y chromosome, offers a better power of discrimination to define even sub-populations of different ethnic groups (9-11). This study aims to compare a sample of Italian men from Brescia (northern Italy) with a sample of men from each of three main ethnic groups living in Brescia county (Albanians, North Africans, Indo-Pakistanis), through STRs and SNPs Y chromosome typing, in order to find the data useful in defining the ethnic origin. 相似文献57.
Rigoli Mattia Facchin Alessio Cardile Davide Beschin Nicoletta Luzzatti Claudio 《Neurological sciences》2021,42(6):2461-2469
Neurological Sciences - The speed of information processing is one of the most reliable indices of cognitive efficiency. The most common way to evaluate this ability is to assess reaction times... 相似文献
58.
59.
Amplified C lambda and c-abl genes are on the same marker chromosome in K562 leukemia cells. 总被引:16,自引:6,他引:16 下载免费PDF全文
J R Selden B S Emanuel E Wang L Cannizzaro A Palumbo J Erikson P C Nowell G Rovera C M Croce 《Proceedings of the National Academy of Sciences of the United States of America》1983,80(23):7289-7292
The human leukemia cell line K562, derived from a patient with Philadelphia chromosome-positive chronic myelogenous leukemia, contains amplified c-abl oncogenes and unrearranged C lambda genes. Using in situ hybridization techniques, we have determined that the amplified c-abl and C lambda DNA sequences of K562 cells are both located on the same abnormal acrocentric marker chromosome, which may represent an altered Philadelphia chromosome. 相似文献
60.
Reactivation of silent rRNA genes by simian virus 40 in human-mouse hybrid cells. 总被引:21,自引:4,他引:21 下载免费PDF全文
K J Soprano V G Dev C M Croce R Baserga 《Proceedings of the National Academy of Sciences of the United States of America》1979,76(8):3885-3889
Mouse-human hybrid cells were used to study the ability of simian virus 40 to regulate the expression of rRNA genes in vivo. In these hybrid cells, only the rRNA genes of the dominant species are expressed; the genes for the rRNA of the recessive species are silent. Simian virus 40 infection of these hybrids led to the production of two distinct 28S rRNA species as analyzed by agarose/2.4% polyacrylamide gel electrophoresis. These species were identified as human and mouse rRNAs. This result was confirmed by histochemical studies which indicated that the nucleolus organizer regions of both mouse and human chromosomes were actively synthesizing rRNA in the virus-infected hybrid cells. These results indicate that simian virus 40 infection can induce the expression of otherwise silent rRNA genes. 相似文献