全文获取类型
收费全文 | 7840篇 |
免费 | 373篇 |
国内免费 | 61篇 |
专业分类
耳鼻咽喉 | 55篇 |
儿科学 | 191篇 |
妇产科学 | 293篇 |
基础医学 | 834篇 |
口腔科学 | 115篇 |
临床医学 | 753篇 |
内科学 | 2058篇 |
皮肤病学 | 110篇 |
神经病学 | 924篇 |
特种医学 | 244篇 |
外科学 | 1151篇 |
综合类 | 25篇 |
预防医学 | 360篇 |
眼科学 | 193篇 |
药学 | 468篇 |
中国医学 | 17篇 |
肿瘤学 | 483篇 |
出版年
2023年 | 48篇 |
2022年 | 97篇 |
2021年 | 175篇 |
2020年 | 122篇 |
2019年 | 146篇 |
2018年 | 170篇 |
2017年 | 141篇 |
2016年 | 167篇 |
2015年 | 198篇 |
2014年 | 261篇 |
2013年 | 341篇 |
2012年 | 527篇 |
2011年 | 539篇 |
2010年 | 300篇 |
2009年 | 334篇 |
2008年 | 527篇 |
2007年 | 573篇 |
2006年 | 574篇 |
2005年 | 484篇 |
2004年 | 437篇 |
2003年 | 335篇 |
2002年 | 337篇 |
2001年 | 103篇 |
2000年 | 100篇 |
1999年 | 90篇 |
1998年 | 80篇 |
1997年 | 67篇 |
1996年 | 64篇 |
1995年 | 41篇 |
1994年 | 36篇 |
1993年 | 62篇 |
1992年 | 112篇 |
1991年 | 58篇 |
1990年 | 80篇 |
1989年 | 67篇 |
1988年 | 60篇 |
1987年 | 49篇 |
1986年 | 44篇 |
1985年 | 39篇 |
1984年 | 58篇 |
1983年 | 31篇 |
1982年 | 23篇 |
1981年 | 27篇 |
1980年 | 16篇 |
1979年 | 22篇 |
1978年 | 15篇 |
1977年 | 10篇 |
1975年 | 8篇 |
1974年 | 11篇 |
1972年 | 7篇 |
排序方式: 共有8274条查询结果,搜索用时 46 毫秒
51.
Raspollini MR Castiglione F Garbini F Villanucci A Amunni G Baroni G Boddi V Taddei GL 《International journal of surgical pathology》2005,13(2):135-142
We analyzed in advanced ovarian serous G3 carcinoma the correlation between epidermal growth factor receptor (EGFR) overexpression and tumor angiogenesis and their relation with clinical outcome. Microvessel density (MVD) and vascular endothelial growth factor (VEGF) were statistically correlated with disease-free interval and death from disease both in univariate and multivariate analyses while EGFR expression was not correlated with clinical outcome. MVD was significantly associated with progression of disease during chemotherapy while VEGF and EGFR expression were not correlated with responsiveness to chemotherapy (Fisher's exact test). VEGF expression was correlated with MVD (Fisher's exact test). EGFR showed a trend to correlation with MVD. Further studies focusing on the use of angiogenesis inhibitors in addition to EGFR inhibitors on ovarian carcinoma cells may produce therapeutic strategies in the selection of tailored therapies in ovarian cancer patients. 相似文献
52.
Biasco Guido Paganelli Gian Maria Psilogenis Mary Nazzari Marco Di Febo Giulio Siringo Sebastiano 《Inflammation research》1992,36(1):C88-C89
The effect on gastric epithelial cell proliferation of small doses of aspirin was evaluated in 9 healthy volunteers, with or without administration of sulglycotide, a sulfated glycopeptide with cytoprotective properties. Cell kinetics study was performed by incubation of gastric biopsies with bromodeoxyuridine (BrdU) and immunohistochemistry. A decrease of BrdU-labeling index and a shortening of the height of gastric columns were observed after treatment with aspirin and placebo. No variations were observed after treatment with aspirin and sulglycotide. A decrease of the epithelial cell renewal could be one of the damaging effects of aspirin on the gastric mucosa. The treatment with sulglycotide seems to be effective to prevent this alteration. 相似文献
53.
A case of extraskeletal osteosarcoma was observed in the thigh of a 33-year-old male patient. Ultrastructurally the tumor was characterized by the presence of a particular dense type of cell, the nucleus of which showed a characteristic combination of features: large amounts of condensed mar-ginated chromatin, prominent perichromatin granules, vermicellar bodies, and undulating microtubules. The tumor also contained intermediate-type cells with a more typical osteoblastic appearance, and more blastic cells. All three cell types contained varying amounts of dilated rough endoplasmic reticulum with prominent inclusions of crystalline material showing a hexagonal or banded pattern, indicating that the cells represent different stages of maturation rather than genuinely different types of cells. Dense cells showing the same characteristic combination of nuclear features have been described once before in a case of parosteal osteosarcoma. Our results indicate that these cells are a particular form of osteogenic cell. The presence of undulating microtubules and vermicellar bodies suggest a possible association with the presence of virus and/or increased levels of interferon. 相似文献
54.
Dario Barbieri Romedio Spanedda Gian Luigi Castoldi 《Cancer Genetics and Cytogenetics》1986,20(3-4):287-292
Cytogenetic studies were performed on the cells of bone marrow, peripheral blood, and skin tumor biopsies from a patient with mycosis fungoides at an early stage. Chromosome abnormalities were detected in 100% of the cells harvested from the cutaneous specimen, whereas the cells of the bone marrow and blood were karyotypically normal. Three related clones, showing increasing cytogenetic complexity, were found. Chromosome #12 was abnormal in all metaphases, and an abnormal 14q chromosome was present in a minority of cells belonging to the most complex emerging subclone. These data, along with the finding of important signs of chromosome imbalance, suggest a polyphasic evolution of this chronic T lymphoproliferative disease. 相似文献
55.
Ricca V Nacmias B Boldrini M Cellini E di Bernardo M Ravaldi C Tedde A Bagnoli S Placidi GF Rotella CM Sorbi S 《Neuroscience letters》2004,365(2):92-96
Various studies have evaluated the possible role of the -1438G/A polymorphism within the 5-HT2A receptor gene in the susceptibility to Eating Disorders (EDs). One hundred and forty-eight ED patients (EDp) and 89 control subjects were interviewed by means of the Eating Disorder Examination (EDE) and analyzed for distribution of the -1438G/A polymorphism. Patients with the AA genotype suffering from Anorexia Nervosa and Bulimia Nervosa showed higher Weight and Shape Concern (P = 0.003 and P = 0.010, respectively) scores and greater overall severity of the ED psychopathology (EDE total score) (P = 0.012). The obtained preliminary data suggest the use of dimensional psychopathological measures in ED genetic studies. 相似文献
56.
d'Amati G Bagattin A Bauce B Rampazzo A Autore C Basso C King K Romeo MD Gallo P Thiene G Danieli GA Nava A 《Human pathology》2005,36(7):761-767
We report on a family with a history of sudden death and effort-induced polymorphic ventricular arrhythmias. The index case was a 17-year-old boy who died suddenly and at postmortem had evidence of fibrofatty replacement in the right ventricular free wall, consistent with arrhythmogenic right ventricular cardiomyopathy, as well as calcium phosphate deposits within the myocytes. A molecular genetics investigation carried out in the paraffin-embedded myocardium of the subject and in blood samples of family members disclosed a missense mutation in exon 3 (230C-->T; A77V) of the cardiac ryanodine receptor type 2 gene. The carriers showed effort-induced polymorphic ventricular tachycardia in the setting of normal resting electrocardiogram and trivial echocardiographic abnormalities, consistent with catecholaminergic polymorphic ventricular tachycardia. The observation of both arrhythmogenic right ventricular cardiomyopathy type 2 and catecholaminergic polymorphic ventricular tachycardia in the same family suggests that the two entities might correspond to different degrees of phenotypic expression of the same disease. This experience underscores the importance of a precise autopsy diagnosis in the case of sudden cardiac death, including molecular genetics, and the mission of pathologists to guide further clinical investigation of family members. 相似文献
57.
58.
59.
Expression of the Bovine Leukemia Virus Envelope Glycoprotein (gp51) by Recombinant Baculovirus and Its Use in an Enzyme-Linked Immunosorbent Assay 下载免费PDF全文
Antonio De Giuseppe Francesco Feliziani Domenico Rutili Gian Mario De Mia 《Clinical and Vaccine Immunology : CVI》2004,11(1):147-151
The gene encoding the major envelope glycoprotein (gp51) with its signal sequence, represented by an additional NH2-terminal 33-residue amino acid sequence of bovine leukemia virus (BLV), was inserted into a baculovirus transfer vector. A recombinant virus expressing a secreted gp51 protein in insect cells was isolated. The recombinant gp51 expressed was characterized by using an anti-BLV monoclonal antibody by both Western blotting analysis and enzyme-linked immunosorbent assay (ELISA). The secreted gp51 was used as an antigen, and an ELISA with recombinant gp51 (rgp51) was developed for the detection of BLV antibodies. This new procedure was compared with a previous ELISA method for the detection of BLV antibodies and an agar gel immunodiffusion test performed with an unpurified BLV antigen preparation. The comparative testing of field samples showed that the ELISA with rgp51 is more specific and also suitable for the testing of pooled sera. 相似文献
60.
Oddsson K Leifels-Fischer B Wiel-Masson D de Melo NR Benedetto C Verhoeven CH Dieben TO 《Human reproduction (Oxford, England)》2005,20(2):557-562
BACKGROUND: This trial was conducted to compare cycle control with vaginal ring a combined contraceptive vaginal ring, and a combined oral contraceptive (COC) delivering 30 mug ethinylestradiol (EE) and 150 mug levonorgestrel. METHODS: This open-label, randomized, multi-centre, Phase III study involved adult women from 11 countries. Subjects were treated with either vaginal ring or a COC for 13 cycles (12 months). RESULTS: A total of 1030 subjects (vaginal ring, n=512; COC, n=518) comprised the intention-to-treat (ITT) population. The percentage of women in the ITT population who completed the trial was 70.9% for vaginal ring and 71.2% for the COC group. The incidence of breakthrough bleeding and spotting over cycles 2-13, the primary efficacy parameter, was lower with vaginal ring (range 2.0-6.4%) than the COC (range 3.5-12.6%), and for cycles 2 and 9 the lower incidence with vaginal ring was confirmed as statistically significant (P=0.003 and P=0.002 respectively). The incidence of intended bleeding was significantly higher over all cycles with vaginal ring (58.8-72.8%) than with the COC (43.4-57.9%). CONCLUSIONS: Cycle control with vaginal ring was excellent and superior to that of a COC containing 30 mug EE. 相似文献