全文获取类型
收费全文 | 5741篇 |
免费 | 347篇 |
国内免费 | 42篇 |
学科分类
医药卫生 | 6130篇 |
出版年
2023年 | 30篇 |
2022年 | 35篇 |
2021年 | 144篇 |
2020年 | 84篇 |
2019年 | 118篇 |
2018年 | 173篇 |
2017年 | 109篇 |
2016年 | 129篇 |
2015年 | 168篇 |
2014年 | 192篇 |
2013年 | 247篇 |
2012年 | 351篇 |
2011年 | 348篇 |
2010年 | 236篇 |
2009年 | 188篇 |
2008年 | 341篇 |
2007年 | 334篇 |
2006年 | 342篇 |
2005年 | 280篇 |
2004年 | 265篇 |
2003年 | 253篇 |
2002年 | 227篇 |
2001年 | 132篇 |
2000年 | 145篇 |
1999年 | 143篇 |
1998年 | 55篇 |
1997年 | 47篇 |
1996年 | 38篇 |
1995年 | 21篇 |
1994年 | 26篇 |
1993年 | 25篇 |
1992年 | 88篇 |
1991年 | 79篇 |
1990年 | 79篇 |
1989年 | 91篇 |
1988年 | 87篇 |
1987年 | 89篇 |
1986年 | 58篇 |
1985年 | 56篇 |
1984年 | 29篇 |
1983年 | 18篇 |
1982年 | 16篇 |
1980年 | 17篇 |
1979年 | 27篇 |
1978年 | 16篇 |
1977年 | 20篇 |
1976年 | 10篇 |
1974年 | 25篇 |
1968年 | 9篇 |
1967年 | 10篇 |
排序方式: 共有6130条查询结果,搜索用时 62 毫秒
1.
2.
Susanna Zanutto Chiara Maura Ciniselli Antonino Belfiore Mara Lecchi Enzo Masci Gabriele Delconte Massimo Primignani Giulia Tosetti Marco Dal Fante Linda Fazzini Aldo Airoldi Marcello Vangeli Francesca Turpini Giovanni Giuseppe Rubis Passoni Paolo Viaggi Monica Arena Roberta Ilaria Olimpia Motta Anna Maria Cantù Cristiano Crosta Giuseppe De Roberto Francesca Iannuzzi Andrea Cassinotti Valentina Dall'Olio Laura Tizzoni Gabriella Sozzi Emanuele Meroni Luigi Bisanti Marco Alessandro Pierotti Paolo Verderio Manuela Gariboldi 《International journal of cancer. Journal international du cancer》2020,146(4):1164-1173
Colorectal cancer (CRC) screening programs help diagnose cancer precursors and early cancers and help reduce CRC mortality. However, currently recommended tests, the fecal immunochemical test (FIT) and colonoscopy, have low uptake. There is therefore a pressing need for screening strategies that are minimally invasive and consequently more acceptable to patients, most likely blood based, to increase early CRC identification. MicroRNAs (miRNAs) released from cancer cells are detectable in plasma in a remarkably stable form, making them ideal cancer biomarkers. Using plasma samples from FIT-positive (FIT+) subjects in an Italian CRC screening program, we aimed to identify plasma circulating miRNAs that detect early CRC. miRNAs were initially investigated by quantitative real-time PCR in plasma from 60 FIT+ subjects undergoing colonoscopy at Fondazione IRCCS Istituto Nazionale dei Tumori, then tested on an internal validation cohort (IVC, 201 cases) and finally in a large multicenter prospective series (external validation cohort [EVC], 1121 cases). For each endoscopic lesion (low-grade adenoma [LgA], high-grade adenoma [HgA], cancer lesion [CL]), specific signatures were identified in the IVC and confirmed on the EVC. A two-miRNA-based signature for CL and six-miRNA signatures for LgA and HgA were selected. In a multivariate analysis including sex and age at blood collection, the areas under the receiver operating characteristic curve (95% confidence interval) of the signatures were 0.644 (0.607–0.682), 0.670 (0.626–0.714) and 0.682 (0.580–0.785) for LgA, HgA and CL, respectively. A miRNA-based test could be introduced into the FIT+ workflow of CRC screening programs so as to schedule colonoscopies only for subjects likely to benefit most. 相似文献
3.
4.
Viviana Maestrini Lucia I. Birtolo Sara Cimino Paolo Severino Massimo Mancone Marco Francone Sanjay M. Banypersad Flavia Ventriglia Luigi Tritapepe Fabio Miraldi Francesco Fedele 《Echocardiography (Mount Kisco, N.Y.)》2019,36(5):992-995
A 20‐year‐old Congolese woman presented with presyncope, dyspnea, and anasarca. Past medical history was unremarkable. Echocardiography revealed a rare combination of giant right atrium (RA), a dilated and hypertrophied right ventricle, subvalvular pulmonary stenosis (subPS), severe tricuspid regurgitation (TR), pericardial effusion and what appeared to be a spontaneously closed ventricular septal defect (VSD). Cardiac Magnetic Resonance and Cardiac Computed Tomography confirmed the findings excluding the presence of intra‐cardiac and extra‐cardiac shunt and other associated congenital anomalies. The patient underwent subPS resection, right atrioplasty, and tricuspid annuloplasty. Multimodality approach facilitated the detection of the abnormalities and provided clarity when determining the optimal surgical strategy. 相似文献
5.
6.
7.
8.
Hyo-Chang Kim Seok-Gu Kang Pil-Woo Huh Do Sung Yoo Kyoung Suok Cho Dal Soo Kim 《Journal of clinical neuroscience》2007,14(11):1135-1139
Pituitary abscess is a rare and potentially lethal condition. Pituitary abscess in a pregnant woman has not been previously described. A 38-year-old pregnant woman (34 weeks gestation) with a pituitary mass complained of a progressive headache and sudden visual impairment. She was afebrile and had no inflammatory symptoms on admission. On MRI, the preoperative diagnosis was pituitary adenoma with sphenoid sinusitis. She underwent an uncomplicated transsphenoidal procedure for removal of the pituitary mass. The next day, labor commenced and a healthy preterm baby was delivered. Pathologic examination of the intrasellar mass showed polymorphonuclear cells, debris and no tumor cells. The sellar contents were cultured and Streptococcus viridans was grown. To our knowledge this is the first case of pituitary abscess reported during pregnancy. Although the patient was pregnant, the transsphenoidal approach was safe for the mother and the fetus. Surgical drainage and antibiotic therapy are required for the definitive treatment of this condition. 相似文献
9.
The prevalence of bad self-rated health (SRH) varies considerably across countries. Here we present the results of a cross-national comparative study based on the data of National Health Surveys conducted in France and Italy. According to these data, 11% of the Italian and 6% of the French adult population aged between 45 and 74 rate their health as bad or very bad. This gap may result from differences in population structure regarding the individual characteristics (sociodemographic characteristics, diseases and disabilities, lifestyle, and others) that impact on SRH i.e., a structural effect. It may also be that the link between these characteristics and SRH is “country-specific” i.e., a contextual effect. We use logistic regression models to assess the contribution of both explanations. We find that the structural effect plays a prominent role in the higher prevalence of bad SRH in Italy compared to France. 相似文献
10.
A. P. Dei Tos Paola Dal Cin 《Virchows Archiv : an international journal of pathology》1997,431(2):83-94
Soft tissue tumours represent a heterogeneous group of mesenchymal lesions, and their classification is the subject of continuous
debate. Chromosome analysis, molecular cytogenetics and molecular assays may become increasingly useful in diagnosis, and
this review summarises advances in the cytogenetic characterisation and classification of soft tissue tumours. Among the group
of fibrous lesions, superficial fibromatosis exhibits trisomy 8. This genomic change is also observed in desmoid fibromatosis
in association with trisomy 20. Trisomy 11 is the most frequently observed chromosomal aberration in congenital fibrosarcoma.
Dermatofibrosarcoma protuberans and giant cell fibroblastoma share a translocation t(17;22), which supports the concept of
the existence of a common differentiation pathway. Adipose tissue tumours is the group in which integration of genetics and
pathology has been most fruitful. Ordinary lipomas cytogenetically show an abnormal karyotype in about half the cases. Genomic
changes of the 11q13 region are observed in hibernoma. Lipoblastoma exhibits a specific 8q rearrangement in 8q11-q13. Loss
of material from the region 16q13-qter and 13q deletions are observed in spindle cell/pleomorphic lipomas. The well-differentiated
liposarcoma/atypical lipoma group is characterised karyotypically by the presence of one extra ring and/or extra giant chromosome
marker. Myxoid and round cell liposarcoma share the same characteristic chromosome change: t(12;16)(q13;p11) in most cases.
In the group of smooth muscle lesions most data are derived from uterine leiomyomas, which can be subclassified cytogenetically
into seven different types. Half of all leiomyomas are chromosomally normal; the other half have one of six possible consistent
chromosome changes. Alveolar rhabdomyosarcoma is characterised cytogenetically by two variant translocations t(2;13)(q35;q14)
and t(1;13)(p36;q14). Among tenosynovial tumours, the localised type of giant cell tumour of tendon sheath exhibits two different
karyotypic changes. One involves 1p11 in a translocation with chromosome 2 or with another chromosome. A second type involves
16q24. Synovial sarcoma is characterised cytogenetically by a translocation occurring between chromosome 18 and presumably
two adjacent loci on the X chromosome. In neural tumours, abnormalities of chromosome 22 have been reported in benign schwannomas
and perineuriomas. Malignant peripheral nerve sheath tumours exist in two main forms: sporadic and associated with the NF-1
syndrome. Karyotypes are very complex, but chromosomes 17q and 22q are very often involved. Clear cell sarcoma is characterised
cytogenetically and molecularly by a translocation t(12;22)(q13;q12). The Ewing’s sarcoma/peripheral neuroectodermal tumour
category shows a central karyotypic anomaly represented by the translocation t(11;22). The two variants t(21;22) and t(7;22)
are found in some cases. Among cartilaginous lesion, the most frequently described anomaly is the t(9;22)(q22;q12) in extraskeletal
myxoid chondrosarcoma. Intra-abdominal desmoplastic small round cell tumour is characterised by a t(11;22)(p13;q12).
Received: 5 February 1997 / Accepted: 24 February 1997 相似文献