全文获取类型
收费全文 | 361篇 |
免费 | 33篇 |
国内免费 | 13篇 |
专业分类
耳鼻咽喉 | 1篇 |
儿科学 | 10篇 |
妇产科学 | 5篇 |
基础医学 | 77篇 |
口腔科学 | 24篇 |
临床医学 | 20篇 |
内科学 | 89篇 |
皮肤病学 | 6篇 |
神经病学 | 4篇 |
特种医学 | 74篇 |
外科学 | 36篇 |
综合类 | 10篇 |
预防医学 | 6篇 |
眼科学 | 2篇 |
药学 | 14篇 |
中国医学 | 3篇 |
肿瘤学 | 26篇 |
出版年
2023年 | 1篇 |
2021年 | 3篇 |
2020年 | 5篇 |
2019年 | 4篇 |
2018年 | 3篇 |
2017年 | 6篇 |
2016年 | 2篇 |
2015年 | 5篇 |
2014年 | 6篇 |
2013年 | 11篇 |
2012年 | 7篇 |
2011年 | 9篇 |
2010年 | 18篇 |
2009年 | 24篇 |
2008年 | 7篇 |
2007年 | 21篇 |
2006年 | 24篇 |
2005年 | 11篇 |
2004年 | 8篇 |
2003年 | 6篇 |
2002年 | 10篇 |
2001年 | 8篇 |
2000年 | 3篇 |
1999年 | 10篇 |
1998年 | 24篇 |
1997年 | 26篇 |
1996年 | 19篇 |
1995年 | 13篇 |
1994年 | 13篇 |
1993年 | 10篇 |
1992年 | 5篇 |
1991年 | 7篇 |
1990年 | 6篇 |
1989年 | 14篇 |
1988年 | 6篇 |
1987年 | 7篇 |
1986年 | 8篇 |
1985年 | 9篇 |
1984年 | 2篇 |
1983年 | 2篇 |
1982年 | 5篇 |
1981年 | 3篇 |
1980年 | 3篇 |
1979年 | 1篇 |
1978年 | 2篇 |
1977年 | 3篇 |
1976年 | 4篇 |
1975年 | 3篇 |
排序方式: 共有407条查询结果,搜索用时 15 毫秒
1.
David M Dohan Joseph Choukroun Antoine Diss Steve L Dohan Anthony J J Dohan Jaafar Mouhyi Bruno Gogly 《Oral surgery, oral medicine, oral pathology, oral radiology, and endodontics》2006,101(3):e37-e44
Platelet-rich fibrin (PRF) belongs to a new generation of platelet concentrates geared to simplified preparation without biochemical blood handling. In this initial article, we describe the conceptual and technical evolution from fibrin glues to platelet concentrates. This retrospective analysis is necessary for the understanding of fibrin technologies and the evaluation of the biochemical properties of 3 generations of surgical additives, respectively fibrin adhesives, concentrated platelet-rich plasma (cPRP) and PRF. Indeed, the 3-dimensional fibrin architecture is deeply dependent on artificial clinical polymerization processes, such as massive bovine thrombin addition. Currently, the slow polymerization during PRF preparation seems to generate a fibrin network very similar to the natural one. Such a network leads to a more efficient cell migration and proliferation and thus cicatrization. 相似文献
2.
Occurrence of the t(2;5)(p23;q35) in non-Hodgkin's lymphoma 总被引:9,自引:3,他引:6
Weisenburger DD; Gordon BG; Vose JM; Bast MA; Chan WC; Greiner TC; Anderson JR; Sanger WG 《Blood》1996,87(9):3860-3868
Primary CD30(Ki-1)-positive anaplastic large-cell lymphoma (ALCL) is considered by some to be a distinct clinicopathologic entity associated with the t(2;5) (p23;q35). However, the specificity of t(2;5) for ALCL has not been carefully studied. Therefore, we performed a detailed analysis of all cases of ALCL with abnormal cytogenetics results in the Nebraska Lymphoma Study Group registry, as well as all other cases of non-Hodgkin's lymphoma with t(2;5) in the registry. We found the t(2;5) in only five of 10 cases of ALCL, four of whom were young patients. However, we also found the t(2;5) in 11 other cases of nonanaplastic lymphoma, including eight children with typical peripheral T-cell lymphomas of various types. The t(2;5) was also found in three older adults with B-cell lymphomas of various types. Thus, the t(2;5) was not specific for CD30+ ALCL. However, t(2;5) may define a clinicopathologic entity in children and young adults characterized by variable morphologies with a T-cell or indeterminate phenotype, CD30-positivity, nodal disease with frequent extranodal involvement, advanced stage, and an excellent response to therapy, including bone marrow transplantation for relapsed disease. The clinical relevance of the t(2;5) in older patients requires further study. 相似文献
3.
4.
Two fast magnetic resonance (MR) imaging techniques, advanced Fourier and partial-flip imaging, were used at 0.35 T to examine 21 patients with suspected intracranial lesions; the results were quantitatively compared with a conventional spin-echo study. Both of the fast MR techniques yielded a fourfold reduction in imaging time per section. The advanced Fourier sequence showed contrast that was identical to the conventional spin-echo study with signal-to-noise ratios of 58% and 57% for the first and second echoes, respectively. The partial-flip sequence showed a contrast of 109% and 57% for lesions versus substantia alba, and 107% and 78% for substantia grisea versus substantia alba relative to the first and second echoes of the conventional spin-echo study. The partial-flip sequence was particularly sensitive to magnetic susceptibility; this produced artifacts that may undermine the usefulness of partial flip for routine screening in certain parts of the brain. However, this susceptibility significantly improved the detection of intracranial hemorrhage when compared with the spin-echo sequence, particularly when combined with phase mapping of the partial-flip study. 相似文献
5.
Low-grade primary B-cell lymphoma of the lung. An immunohistochemical, molecular, and cytogenetic study of a single case 总被引:6,自引:0,他引:6
A C Wotherspoon G N Soosay T C Diss P G Isaacson 《American journal of clinical pathology》1990,94(5):655-660
A case of primary low-grade pulmonary lymphoma is described. The histologic features conformed to those laid down by Saltzstein for a diagnosis of "pseudolymphoma." However, the immunocytochemical and molecular investigations confirmed the tumor to be a low-grade B-cell lymphoma of mucosa-associated lymphoid tissue (MALT). Cytogenetic studies revealed an abnormal karyotype with a translocation t(1;14). This is the first reported case of an abnormal karyotype in a case of a lymphoma of MALT. 相似文献
6.
Hart TC; Bowden DW; Bolyard J; Kula K; Hall K; Wright JT 《Human molecular genetics》1997,6(13):2279-2284
Tricho-dento-osseous syndrome (TDO), MIM# 190320, is transmitted as a
highly penetrant autosomal dominant trait that is characterized by variable
clinical expression. The principal clinical features include kinky/curly
hair in infancy, enamel hypoplasia, taurodontism, as well as increased
thickness and density of cranial bones. Possible genetic linkage has been
reported for TDO with the ABO blood group locus, but the gene defect
remains unknown. We have identified four multiplex families (n = 63, 39
affected, 24 unaffected) from North Carolina segregating TDO. We previously
have excluded a major locus for TDO in the ABO region for these families.
Utilizing a genome-wide search strategy, we obtained conclusive evidence
for linkage of the TDO syndrome locus to markers on chromosome 17q21
(D17S791, Z max = 10.54, Theta = 0.00) with no indication of genetic
heterogeneity. Multipoint analysis suggests the TDO locus is located in a 7
cM chromosomal segment flanked by D17S932 and D17S941. This finding
represents the first step towards isolation and cloning of the TDO gene.
Identification of this gene has important implications for understanding
normal and abnormal craniofacial development of hair, teeth and bone.
相似文献
7.
Missense mutation in a von Willebrand factor type A domain of the alpha 3(VI) collagen gene (COL6A3) in a family with Bethlem myopathy 总被引:2,自引:0,他引:2
Pan TC; Zhang RZ; Pericak-Vance MA; Tandan R; Fries T; Stajich JM; Viles K; Vance JM; Chu ML; Speer MC 《Human molecular genetics》1998,7(5):807-812
The Bethlem myopathy is a rare autosomal dominant proximal myopathy
characterized by early childhood onset and joint contractures. Evidence for
linkage and genetic heterogeneity has been established, with the majority
of families linked to 21q22.3 and one large family linked to 2q37,
implicating the three type VI collagen subunit genes, COL6A1 (chromosome
21), COL6A2 (chromosome 21) and COL6A3 (chromosome 2) as candidate genes.
Mutations of the invariant glycine residues in the triple-helical
domain-coding region of COL6A1 and COL6A2 have been reported previously in
the chromosome 21-linked families. We report here the identification of a
G-->A mutation in the N-terminal globular domain-coding region of COL6A3
in a large American pedigree (19 affected, 12 unaffected), leading to the
substitution of glycine by glutamic acid in the N2 motif, which is
homologous to the type A domains of the von Willebrand factor. This
mutation segregated to all affected family members, to no unaffected family
members, and was not identified in 338 unrelated Caucasian control
chromosomes. Thus mutations in either the triple-helical domain or the
globular domain of type VI collagen appear to cause Bethlem myopathy.
相似文献
8.
Twenty frozen and 55 paraffin sections of lymphnode specimens from 55 patients with pretreatment Hodgkin's disease (nodular sclerosis Hodgkin's disease, n = 45; mixed cellularity Hodgkin's disease, n = 10) were studied by immunohistochemistry and molecular analysis to determine the phenotype of Hodgkin's and Reed-Sternberg cells (HRS). In all cases the HRS cells were CD45-, and CD30+, and in 43/55 (78%) cases they were CD15+. In 48/55 cases (87%) HRS cells were reactive with at least one B-cell marker (CD19, CD20, CD22, CDw75, MB2), 8/55 cases (14.5%) showed reactivity (mainly cytoplasmic) of a subpopulation of HRS cells with the T-cell markers CD3 and beta F1. All cases that expressed T-cell antigens were also reactive with at least one B-cell marker. In frozen sections, a minority of HRS cells in each case studied showed cytoplasmic positivity for bcl-2 protein. Rearrangement of immunoglobulin heavy chain genes was detected in one case and of T-cell receptor beta chain genes in none. The authors were unable to confirm previous reports of bcl-2 gene rearrangement in Hodgkin's disease. The results strongly support a B lymphocytic origin of HRS cells. 相似文献
9.
In ovarian neoplasms, BRAF, but not KRAS, mutations are restricted to low-grade serous tumours 总被引:7,自引:0,他引:7
Sieben NL Macropoulos P Roemen GM Kolkman-Uljee SM Jan Fleuren G Houmadi R Diss T Warren B Al Adnani M De Goeij AP Krausz T Flanagan AM 《The Journal of pathology》2004,202(3):336-340
Genes of the RAF family, which mediate cellular responses to growth signals, encode kinases that are regulated by RAS and participate in the RAS/RAF/MEK/ERK/MAP-kinase pathway. Activating mutations in BRAF have recently been identified in melanomas, colorectal cancers, and thyroid and ovarian tumours. In the present study, an extensive characterization of BRAF and KRAS mutations has been performed in 264 epithelial and non-epithelial ovarian neoplasms. The epithelial tumours ranged from adenomas and borderline neoplasms to invasive carcinomas including serous, mucinous, clear cell, and endometrioid lesions. It is shown that BRAF mutations in ovarian tumours occur exclusively in low-grade serous neoplasms (33 of 91, 36%); these included serous borderline tumours (typical and micropapillary variants), an invasive micropapillary carcinoma and a psammocarcinoma. KRAS mutations were identified in 26 of 91 (29.5%) low-grade serous tumours, 7 of 49 (12%) high-grade serous carcinomas, 2 of 6 mucinous adenomas, 22 of 28 mucinous borderline tumours, and 10 of 18 mucinous carcinomas. Of note, two serous borderline tumours were found to harbour both BRAF and KRAS mutations. The finding that at least 60% of serous borderline tumours harbour mutations in two members of the ERK-MAP-kinase pathway (BRAF 36%, KRAS 30%) compared with 12% of high-grade serous carcinomas (BRAF 0%, KRAS 12%) indicates that the majority of serous borderline tumours do not progress to serous carcinomas. Furthermore, no BRAF mutations were detected in the other 173 ovarian tumours in this study. 相似文献
10.