全文获取类型
收费全文 | 1046篇 |
免费 | 42篇 |
国内免费 | 3篇 |
专业分类
耳鼻咽喉 | 6篇 |
儿科学 | 23篇 |
妇产科学 | 26篇 |
基础医学 | 172篇 |
口腔科学 | 6篇 |
临床医学 | 100篇 |
内科学 | 178篇 |
皮肤病学 | 32篇 |
神经病学 | 57篇 |
特种医学 | 75篇 |
外科学 | 141篇 |
综合类 | 5篇 |
预防医学 | 105篇 |
眼科学 | 2篇 |
药学 | 62篇 |
中国医学 | 3篇 |
肿瘤学 | 98篇 |
出版年
2022年 | 13篇 |
2021年 | 23篇 |
2020年 | 6篇 |
2019年 | 12篇 |
2018年 | 23篇 |
2017年 | 5篇 |
2016年 | 8篇 |
2015年 | 8篇 |
2014年 | 15篇 |
2013年 | 34篇 |
2012年 | 57篇 |
2011年 | 67篇 |
2010年 | 34篇 |
2009年 | 31篇 |
2008年 | 73篇 |
2007年 | 87篇 |
2006年 | 90篇 |
2005年 | 72篇 |
2004年 | 71篇 |
2003年 | 70篇 |
2002年 | 51篇 |
2001年 | 9篇 |
2000年 | 6篇 |
1999年 | 16篇 |
1998年 | 11篇 |
1997年 | 7篇 |
1996年 | 12篇 |
1995年 | 4篇 |
1994年 | 11篇 |
1993年 | 9篇 |
1992年 | 9篇 |
1991年 | 11篇 |
1990年 | 10篇 |
1989年 | 13篇 |
1988年 | 9篇 |
1987年 | 18篇 |
1986年 | 12篇 |
1985年 | 9篇 |
1984年 | 5篇 |
1979年 | 5篇 |
1978年 | 6篇 |
1975年 | 3篇 |
1974年 | 5篇 |
1972年 | 6篇 |
1971年 | 2篇 |
1970年 | 4篇 |
1969年 | 4篇 |
1968年 | 4篇 |
1966年 | 3篇 |
1965年 | 4篇 |
排序方式: 共有1091条查询结果,搜索用时 15 毫秒
31.
Barriers and facilitators of evidence-based practice perceived by behavioral science health professionals 总被引:1,自引:0,他引:1
Pagoto SL Spring B Coups EJ Mulvaney S Coutu MF Ozakinci G 《Journal of clinical psychology》2007,63(7):695-705
Progress in implementing evidence-based behavioral practices has been slow. A qualitative study was performed to characterize the major facilitators and barriers to evidence-based practice (EBP) perceived by behavioral professionals. Members of professional e-mail listservs were queried and 84 barriers and 48 facilitators were nominated by 37 respondents. Thematic analysis revealed seven themes to describe both barriers and facilitators: (a) training, (b) attitudes, (c) consumer demand, (d) logistical considerations, (e) institutional support, (f) policy, and (g) evidence. Most frequently cited barriers included negative attitudes about EBP and lack of training. Barriers also reflected confusion between EBP and the products of EBP (i.e., empirically supported treatments [ESTs]). Main facilitators included a growing evidence base. Results suggest that uptake of EBP may be facilitated by education and training. 相似文献
32.
Bani D Flagiello D Poupon MF Nistri S Poirson-Bichat F Bigazzi M Bani Sacchi T 《Virchows Archiv : an international journal of pathology》1999,435(5):509-519
Previous studies showed that the hormone relaxin acts on human breast cancer MCF-7 cells in vitro by modulating cell proliferation
and promoting cell differentiation toward a duct epithelial phenotype. The present study was designed to investigate whether
relaxin retains these properties when acting in vivo on MCF-7 cell tumors developed in athymic nude mice. Mice bearing MCF-7
cell tumors transplanted under the mammary fat pad and estrogenized to sustain tumor growth were treated systemically with
relaxin (10 μg/day) for 19 days. Vehicle-treated mice were used as controls. Thirty days later, the mice were sacrificed and
tumor fragments were analyzed by light and electron microscopy and immunocytochemistry. Measurements of tumor volume were
recorded weekly for the overall experimental period. The results obtained indicate that relaxin treatment promotes differentiation
of tumor cells towards both myoepithelial-like and epithelial-like cells, as judged by the ultrastructural features of the
cells and by the increased expression of smooth muscle actin and cadherins. Measurements of tumor size and of the number of
cycling cells show that relaxin, at the doses and times of exposure used in this study, does not significantly influence tumor
growth and cell proliferation.
Received: 3 March 1999 / Accepted: 28 May 1999 相似文献
33.
Saugier-Veber P Bonnet C Afenjar A Drouin-Garraud V Coubes C Fehrenbach S Holder-Espinasse M Roume J Malan V Portnoi MF Jeanne N Baumann C Héron D David A Gérard M Bonneau D Lacombe D Cormier-Daire V Billette de Villemeur T Frébourg T Bürglen L 《Human mutation》2007,28(11):1098-1107
Sotos syndrome is an overgrowth syndrome characterized by distinctive facial features, learning difficulties, and macrocephaly with frequent pre- and postnatal overgrowth with advanced bone age. Here, we report on our experience in the molecular diagnostic of Sotos syndrome on 116 patients. Using direct sequencing and a quantitative multiplex PCR of short fluorescent fragments (QMPSF)-based assay allowing accurate detection of both total and partial NSD1 deletions, we identified NSD1 abnormalities in 104 patients corresponding to 102 Sotos families (90%). NSD1 point mutations were detected in 80% of the index cases, large deletions removing the NSD1 gene entirely in 14%, and intragenic NSD1 rearrangements in 6%. Among the 69 detected distinct point mutations, 48 were novel. The QMPSF assay detected an exonic duplication and a mosaic partial deletion. QMPSF mapping of the 15 large deletions revealed the heterogeneity of the deletions, which vary in size from 1 to 4.5 Mb. Clinical features of NSD1-positive Sotos patients revealed that the phenotype in patients with nontruncating mutations was less severe that in patients with truncating mutations. This study confirms the heterogeneity of NSD1 alterations in Sotos syndrome and therefore the need to complete sequencing analysis by screening for partial deletions and duplications to ensure an accurate molecular diagnosis of this syndrome. 相似文献
34.
Hyon C Marlin S Chantot-Bastaraud S Mabboux P Beaujard MP Al Ageeli E Vazquez MP Picard A Siffroi JP Portnoï MF 《European journal of medical genetics》2011,54(3):122-291
Submicroscopic duplications of the genomic interval deleted in Miller-Dieker syndrome (MDS) were recently identified by array-based comparative genomic hybridization (a-CGH) studies, describing new genomic disorders in the MDS locus. These rearrangements of varying size, from 59-88 kb to 4 Mb, were non-recurrent, and appear to result from diverse molecular mechanisms. Only five patients had overlapping 17p13.3 duplications including the entire MDS critical region. We describe here a 13-year-old girl with a novel microduplication of the MDS critical region, involving the PAFAH1B1 and YWHAE genes. She presented with moderate psychomotor retardation, speech delay, behavioral problems, and bilateral cleft lip and palate, a previously unreported manifestation. Initially diagnosed as having an apparently simple terminal Xq26 deletion on standard cytogenetic analysis, she was found to have an associated terminal 4.2 Mb 17p13.3 submicroscopic duplication, identified by subtelomere FISH analysis, further characterized by high-resolution array CGH, resulting from an unbalanced X;17 translocation. Phenotypic comparison with the 5 other patients previously described, revealed common phenotypic features, such as hypotonia, mild to moderate developmental delay/mental retardation, speech abnormalities, behavioral problems, recurrent infections, relatively increase of body weight, discrete facial dysmorphism including downslanting palpebral fissures, broad midface, pointed chin, contributing to further delineate this new 17p13.3 microduplication syndrome. 相似文献
35.
Stasinopoulos I Penet MF Chen Z Kakkad S Glunde K Bhujwalla ZM 《NMR in biomedicine》2011,24(6):636-647
The integration of chemistry and molecular biology with imaging is providing some of the most exciting opportunities in the treatment of cancer. The field of theranostic imaging, where diagnosis is combined with therapy, is particularly suitable for a disease as complex as cancer, especially now that genomic and proteomic profiling can provide an extensive 'fingerprint' of each tumor. Using this information, theranostic agents can be shaped for personalized treatment to target specific compartments, such as the tumor microenvironment (TME), whilst minimizing damage to normal tissue. These theranostic agents can also be used to target multiple pathways or networks by incorporating multiple small interfering RNAs (siRNAs) within a single agent. A decade ago genetic alterations were the primary focus in cancer research. Now it is apparent that the tumor physiological microenvironment, interactions between cancer cells and stromal cells, such as endothelial cells, fibroblasts and macrophages, the extracellular matrix (ECM), and a host of secreted factors and cytokines, influence progression to metastatic disease, aggressiveness and the response of the disease to treatment. In this review, we outline some of the characteristics of the TME, describe the theranostic agents currently available to target the TME and discuss the unique opportunities the TME provides for the design of novel theranostic agents for cancer therapy. 相似文献
36.
Marie-Paule Beaujard Sandra Chantot Michle Dubois Boris Keren Wassila Carpentier Philippe Mabboux Sandra Whalen Michel Vodovar Jean-Pierre Siffroi Marie-France Portnoï 《European journal of medical genetics》2009,52(5):321-327
Despite the heterogeneous clinical presentations, the majority of patients with 22q11.2 deletion syndrome (22q11.2 DS) have either a common recurrent 3 Mb deletion or a less common, 1.5 Mb nested deletion, with breakpoint sites in flanking low-copy repeats (LCR) sequences. Only a small number of atypical deletions have been reported and precisely defined. Haploinsufficiency of the TBX1 gene was determined to be the likely cause of 22q11.2 DS. The diagnostic procedure usually used is FISH using commercially probes (N25 or TUPLE1). However, this test does not contain TBX1, and fails to detect deletions that are either proximal or distal to the FISH probes. Here, we report on two patients with clinical features suggestive of 22q11.2 DS, a male infant with facial dysmorphia, pulmonary atresia, ventricular septal defect, neonatal hypocalcemia, and his affected mother, with facial dysmorphia, learning disabilities, and hypernasal speech. They were tested negative for 22q11.2 DS using N25 or TUPLE1 probes, but were shown deleted for a probe containing TBX1. Delineation of the deletion was performed using high-density SNP arrays (Illumina, 370K). This atypical deletion was spanning 1.89 Mb. The distal breakpoint resided in LCR-D, sharing the same distal breakpoint with the 3 Mb common deletion. The proximal breakpoint was located 105 kb telomeric to TUPLE1, representing a new breakpoint variant that does not correspond to known LCRs of 22q11.2. We conclude that FISH with the TBX1 probe is an accurate diagnostic tool for 22q11.2 DS, with a higher sensitivity than FISH using standard probes, detecting all but the rarest deletions, greatly reducing the false negative rate. 相似文献
37.
dit Faute MA Laurent L Ploton D Poupon MF Jardillier JC Bobichon H 《Clinical & experimental metastasis》2002,19(2):161-168
Growth of human tumor cells as three-dimensional (3D) multicellular spheroids modifies their invasive properties. Here we study the differences in the biological features of MCF-7, a human breast cancer cell line, and its multidrug resistant variant (MDR-MCF-7) cultured as spheroids or as monolayers. Three-dimensional culture decreased the proliferative rate of both cell lines, reduced the drug sensitivity of MCF-7 cells and did not affect the resistance of MDR-MCF-7 cells. Transmission electron microscopic studies and intercellular junctions labeling showed that MCF-7 spheroids had a junctional system involving E-cadherin, tight-junctions and desmosomes. In MDR-MCF-7 cell spheroids, cell cohesion was mostly due to membrane interdigitations. MDR-MCF-7 cells, but not their parental counterpart, displayed a higher invasive potential when cultured as spheroids, as shown in the Boyden chamber assay. 3D-induced invasiveness was correlated with serine protease and plasminogen activator (PA) secretion. MCF-7 cells did not show any tendency to invade, whatever the mode of culture. These results show that 3D-cultures as spheroids distinctively altered structural features of parental and MDR-MCF-7 cells. In MCF-7 cells, 3D-culture increased cell-cell contacts and drug resistance; in MDR-MCF-7 cells, it induced invasive properties. 相似文献
38.
The aims of this study were 1) to develop methods of objectively measuring fear in weaned lambs, and 2) to evaluate the effects of age, sex, breed, and rearing conditions on fear reactions. Four hundred forty-one lambs, aged 3 to 6 months, were submitted to three fear-eliciting situations (isolation, surprise effect, and human presence). Factor analysis revealed a first factor, interpreted in terms of fear, that accounted for 40% of total variance in the three tests. As in adult sheep, the main signs of fear were inhibition of feeding, long distance from the frightening stimulus, frequent immobilizations, and numerous high-pitch bleats. Behavior was also influenced by differences in general locomotor activity and exploratory motivation. Fear reactions were influenced by age (3- to 4-month-old lambs more fearful than 5- to 6-month-old), sex (females more fearful than males), breed (Romanov more fearful than Ile-de-France), and rearing conditions (artificial vs. maternal: almost no influence in males and influence in females depending on age). These results with sheep provide interesting theoretical and practical perspectives to the study of fearfulness. 相似文献
39.
40.
Pascale Dewachter Dominique Laroche Claudie Mouton-Faivre Evelyne Bloch-Morot Jean-Pierre Cercueil Liliane Metge Marie-France Carette Marie-Claude Vergnaud Olivier Clément 《European journal of radiology》2011,77(3):495-501